WASHINGTON - The widely used diabetes drug Avandia should remain on the market, government health advisers recommended Monday, saying evidence of an increased risk of heart attack doesn't merit removal.
The nonbinding recommendation to the Food and Drug Administration came on a majority vote by the panel. The tally wasn't immediately available.
"We're being asked today to take a very draconian action based on studies that have very significant weaknesses and are inadequate for us to make that kind of decision," said Rebecca Killion, a Bowie, Md., diabetic and the panel's patient representative.
However, in an earlier 20-3 vote, the panelists said that available data show the drug does increase heart risks. Panelists said the drug's warning label should be updated and there should be additional study.
Earlier, FDA scientist Dr. David Graham told the joint panel of experts that the drug's heart risks, combined with its lack of unique short-term benefits in helping diabetics control blood sugar, meant continued sales were not justified.
The manufacturer, GlaxoSmithKline PLC, argued that there is no increased risk, citing its own analyses of studies of Avandia, also called rosiglitazone.
"The number of myocardial infarctions is small, the data are inconsistent and there is no overall evidence rosiglitazone is different from any other oral antidiabetes agents," said Dr. Ronald Krall, the company's senior vice president and chief medical officer.
The FDA convened the experts to consider whether Avandia should be restricted to use in select patients and branded with prominent warnings or removed altogether from sale. Previously, the FDA had said information from dozens of studies pointed to an increased risk of heart attack.
The FDA isn't required to follow the advice of its advisory committees but usually does.
About 1 million Americans with Type 2 diabetes use Avandia to control blood sugar by increasing the body's sensitivity to insulin. That sort of treatment has long been presumed to lessen the heart risks already associated with the disease, which is linked to obesity. News that Avandia might actually increase those risks would represent a "serious limitation" of the drug's benefit, according to the FDA.
Monday, July 30, 2007
Exercise, caffeine can fight skin cancer
WASHINGTON - Can adding a cup or two of coffee to the exercise routine increase protection from skin cancer? New research indicates that just might be the case.
The combination of exercise and caffeine increased destruction of precancerous cells that had been damaged by the sun's ultraviolet-B radiation, according to a team of researchers at Rutgers University.
Americans suffer a million new cases of skin cancer every year, according to the National Cancer Institute.
In mice there is a protective effect from both caffeine and voluntary exercise, and when both are combined the protection is even more than the sum of the two, said Dr. Allan H. Conney of the laboratory for cancer research at Rutgers.
"We think it likely that this will extrapolate to humans, but that has to be tested," Conney said in a telephone interview.
Nonetheless, he added, people should continue to use sunscreen.
Exposing the mice to ultraviolet-B light causes some skin cells to become precancerous.
Cells with damaged DNA are programmed to self-destruct, a process called apoptosis, but not all do that, and damaged cells can become cancerous.
The researchers report in Tuesday's issue of Proceedings of the National Academy of Sciences that they studied hairless mice in four groups. Some were fed water containing caffeine, some had wheels on which they could run, some had both and a control group had neither.
"The most dramatic and obvious difference between the groups came from the caffeine-drinking runners, a difference that can likely be attributed to some kind of synergy," Conney said.
Compared with the control animals, those drinking caffeine had a 95 percent increase in apoptosis in damaged cells. The exercisers showed a 120 percent increase, and the mice that were both drinking and running showed a nearly 400 percent increase.
Just what is causing that to happen is not yet clear, though the researchers have several theories.
"We need to dig deeper into how the combination of caffeine and exercise is exerting its influence at the cellular and molecular levels, identifying the underlying mechanisms," Conney said.
"With an understanding of these mechanisms we can then take this to the next level, going beyond mice in the lab to human trials," he said. "With the stronger levels of UVB radiation evident today and an upward trend in the incidence of skin cancer among Americans, there is a premium on finding novel ways to protect our bodies from sun damage."
Conney said the researchers were originally interested in the effects of green tea in preventing skin cancer and were doing tests on regular and decaffeinated teas.
They found the regular tea had an effect, but not the decaffeinated brew.
And, he said, researchers also observed that mice drinking caffeine were more active than those that didn't get it, so they decided to study the effects of exercise too.
They put running wheels into some of the cages. The mice "love to go on it," he said, and will jump on the wheels and run for several minutes, then get off for a while, and then get on and run some more.
And they found that both caffeine and exercise helped eliminate damaged skin cells, but the combination worked better than either alone.
"What we would like to see next is a clinical trial in people," Conney said.
Dr. Michael H. Gold, a Nashville, Tenn., dermatologist and a spokesman for the Skin Cancer Foundation, said he believes "the concept of systemic caffeine should be addressed further."
"I think the concept potentially has a lot of merit," he said in a telephone interview. But mice and humans are different and studies need to be done to be sure this also applies to people.
In the meantime, he said: "If you go outside, you have to wear a sunscreen ... it has to be caffeine and exercise with your sunscreen."
___
On the Net:
Proceedings of the National Academy of Sciences: http://www.pnas.org
The combination of exercise and caffeine increased destruction of precancerous cells that had been damaged by the sun's ultraviolet-B radiation, according to a team of researchers at Rutgers University.
Americans suffer a million new cases of skin cancer every year, according to the National Cancer Institute.
In mice there is a protective effect from both caffeine and voluntary exercise, and when both are combined the protection is even more than the sum of the two, said Dr. Allan H. Conney of the laboratory for cancer research at Rutgers.
"We think it likely that this will extrapolate to humans, but that has to be tested," Conney said in a telephone interview.
Nonetheless, he added, people should continue to use sunscreen.
Exposing the mice to ultraviolet-B light causes some skin cells to become precancerous.
Cells with damaged DNA are programmed to self-destruct, a process called apoptosis, but not all do that, and damaged cells can become cancerous.
The researchers report in Tuesday's issue of Proceedings of the National Academy of Sciences that they studied hairless mice in four groups. Some were fed water containing caffeine, some had wheels on which they could run, some had both and a control group had neither.
"The most dramatic and obvious difference between the groups came from the caffeine-drinking runners, a difference that can likely be attributed to some kind of synergy," Conney said.
Compared with the control animals, those drinking caffeine had a 95 percent increase in apoptosis in damaged cells. The exercisers showed a 120 percent increase, and the mice that were both drinking and running showed a nearly 400 percent increase.
Just what is causing that to happen is not yet clear, though the researchers have several theories.
"We need to dig deeper into how the combination of caffeine and exercise is exerting its influence at the cellular and molecular levels, identifying the underlying mechanisms," Conney said.
"With an understanding of these mechanisms we can then take this to the next level, going beyond mice in the lab to human trials," he said. "With the stronger levels of UVB radiation evident today and an upward trend in the incidence of skin cancer among Americans, there is a premium on finding novel ways to protect our bodies from sun damage."
Conney said the researchers were originally interested in the effects of green tea in preventing skin cancer and were doing tests on regular and decaffeinated teas.
They found the regular tea had an effect, but not the decaffeinated brew.
And, he said, researchers also observed that mice drinking caffeine were more active than those that didn't get it, so they decided to study the effects of exercise too.
They put running wheels into some of the cages. The mice "love to go on it," he said, and will jump on the wheels and run for several minutes, then get off for a while, and then get on and run some more.
And they found that both caffeine and exercise helped eliminate damaged skin cells, but the combination worked better than either alone.
"What we would like to see next is a clinical trial in people," Conney said.
Dr. Michael H. Gold, a Nashville, Tenn., dermatologist and a spokesman for the Skin Cancer Foundation, said he believes "the concept of systemic caffeine should be addressed further."
"I think the concept potentially has a lot of merit," he said in a telephone interview. But mice and humans are different and studies need to be done to be sure this also applies to people.
In the meantime, he said: "If you go outside, you have to wear a sunscreen ... it has to be caffeine and exercise with your sunscreen."
___
On the Net:
Proceedings of the National Academy of Sciences: http://www.pnas.org
Expert: Diabetes drug should be pulled
WASHINGTON - The widely used diabetes drug Avandia should be pulled from the market because of heart risks, a federal scientist said Monday.
Those risks, combined with no unique short-term benefits in helping diabetics control blood-sugar levels, fail to justify keeping Avandia on the market, according to a copy of a slide presentation by Food and Drug Administration scientist Dr. David Graham.
The document was distributed at the onset of a daylong meeting of a joint panel of outside experts convened to consider whether the drug should be restricted to use in select patients and branded with prominent warnings or removed altogether from sale. Previously, the FDA said information from dozens of studies of the GlaxoSmithKline PLC drug points to an increased risk of heart attack.
Glaxo officials, meanwhile, disputed that claim, citing their own analyses of studies of Avandia, also called rosiglitazone.
"The number of myocardial infarctions is small, the data are inconsistent and there is no overall evidence rosiglitazone is different from any other oral antidiabetes agents," said Dr. Ronald Krall, the company's senior vice president and chief medical officer.
The FDA isn't required to follow the advice of its advisory committees but usually does.
The FDA moved up the date of Monday's meeting following the May publication of a study by The New England Journal of Medicine that generated new concerns about Avandia's safety. The pooled analysis of 42 studies revealed a 43 percent higher risk of heart attack for those taking Avandia compared with people taking other diabetes drugs or no diabetes medication.
Glaxo, meanwhile, says its own data show no increase in heart risks with Avandia compared with other diabetes drugs, including Actos. The FDA's Graham, in his presentation, said Avandia does increase heart risks — something Actos, from Takeda Pharmaceuticals, does not do.
About 1 million Americans with Type 2 diabetes use Avandia to control blood sugar by increasing the body's sensitivity to insulin. That sort of treatment has long been presumed to lessen the heart risks already associated with the disease, which is linked to obesity. News that Avandia might actually increase those risks would represent a "serious limitation" of the drug's benefit, according to the FDA.
___
On the Net:
Avandia: http://www.avandia.com/
Food and Drug Administration: http://www.fda.gov/
Those risks, combined with no unique short-term benefits in helping diabetics control blood-sugar levels, fail to justify keeping Avandia on the market, according to a copy of a slide presentation by Food and Drug Administration scientist Dr. David Graham.
The document was distributed at the onset of a daylong meeting of a joint panel of outside experts convened to consider whether the drug should be restricted to use in select patients and branded with prominent warnings or removed altogether from sale. Previously, the FDA said information from dozens of studies of the GlaxoSmithKline PLC drug points to an increased risk of heart attack.
Glaxo officials, meanwhile, disputed that claim, citing their own analyses of studies of Avandia, also called rosiglitazone.
"The number of myocardial infarctions is small, the data are inconsistent and there is no overall evidence rosiglitazone is different from any other oral antidiabetes agents," said Dr. Ronald Krall, the company's senior vice president and chief medical officer.
The FDA isn't required to follow the advice of its advisory committees but usually does.
The FDA moved up the date of Monday's meeting following the May publication of a study by The New England Journal of Medicine that generated new concerns about Avandia's safety. The pooled analysis of 42 studies revealed a 43 percent higher risk of heart attack for those taking Avandia compared with people taking other diabetes drugs or no diabetes medication.
Glaxo, meanwhile, says its own data show no increase in heart risks with Avandia compared with other diabetes drugs, including Actos. The FDA's Graham, in his presentation, said Avandia does increase heart risks — something Actos, from Takeda Pharmaceuticals, does not do.
About 1 million Americans with Type 2 diabetes use Avandia to control blood sugar by increasing the body's sensitivity to insulin. That sort of treatment has long been presumed to lessen the heart risks already associated with the disease, which is linked to obesity. News that Avandia might actually increase those risks would represent a "serious limitation" of the drug's benefit, according to the FDA.
___
On the Net:
Avandia: http://www.avandia.com/
Food and Drug Administration: http://www.fda.gov/
Saturday, July 28, 2007
Diabetics may do well on Mediterranean diet
NEW YORK (Reuters Health) - Eating a traditional Mediterranean diet -- more vegetables, fruits, and fish, and fewer animal products -- does seem to ward off heart disease, an Australian study shows, and it may be especially beneficial for people with diabetes.
Mediterranean-born immigrants in Australia have lower death rates from heart disease than native-born Australians, note Dr. Linton R. Harriss, from Monash University in Melbourne, and colleagues. This prompted them to investigate dietary patterns in relation to heart-related mortality "in an ethnically diverse population."
The study involved over 40,000 men and women, aged between 40 and 69 years, 24 percent of whom were native-born Mediterranean while the rest were native-born Australian. They were followed for ten years.
The researchers used food questionnaires to calculate participants' intake of Mediterranean foods, vegetables, fruits, and meats. The results of the study are published in The American Journal of Clinical Nutrition.
"Those people in our study that were in the highest category of the Mediterranean foods pattern (i.e. most frequently consumed traditional Mediterranean foods) had a 30 percent lower risk of dying from cardiovascular disease compared to those who were in the lowest category," Harriss told Reuters Health.
The investigators found that a Mediterranean-style diet "may be most beneficial for persons with diabetes."
Among the study participants with diabetes, Harriss said, "Our results suggest that the Mediterranean diet may lower mortality from ischemic heart disease." However, because those results are based on a small sub-sample, "more research needs to be performed to investigate these findings better."
The protective effect of a Mediterranean diet pattern against heart-related death was strongest in people who were free of heart disease at the outset. Nonetheless, "the Mediterranean foods pattern showed benefits whether we included or excluded people with a history of cardiovascular disease," Harriss said.
SOURCE: The American Journal of Clinical Nutrition, July 2007
Mediterranean-born immigrants in Australia have lower death rates from heart disease than native-born Australians, note Dr. Linton R. Harriss, from Monash University in Melbourne, and colleagues. This prompted them to investigate dietary patterns in relation to heart-related mortality "in an ethnically diverse population."
The study involved over 40,000 men and women, aged between 40 and 69 years, 24 percent of whom were native-born Mediterranean while the rest were native-born Australian. They were followed for ten years.
The researchers used food questionnaires to calculate participants' intake of Mediterranean foods, vegetables, fruits, and meats. The results of the study are published in The American Journal of Clinical Nutrition.
"Those people in our study that were in the highest category of the Mediterranean foods pattern (i.e. most frequently consumed traditional Mediterranean foods) had a 30 percent lower risk of dying from cardiovascular disease compared to those who were in the lowest category," Harriss told Reuters Health.
The investigators found that a Mediterranean-style diet "may be most beneficial for persons with diabetes."
Among the study participants with diabetes, Harriss said, "Our results suggest that the Mediterranean diet may lower mortality from ischemic heart disease." However, because those results are based on a small sub-sample, "more research needs to be performed to investigate these findings better."
The protective effect of a Mediterranean diet pattern against heart-related death was strongest in people who were free of heart disease at the outset. Nonetheless, "the Mediterranean foods pattern showed benefits whether we included or excluded people with a history of cardiovascular disease," Harriss said.
SOURCE: The American Journal of Clinical Nutrition, July 2007
Friday, July 27, 2007
Sunlight in Youth Might Shield Against MS
FRIDAY, July 27 (HealthDay News) -- A new study of identical twins suggests that children who spend more time in the sun have a lower risk for developing multiple sclerosis (MS) as adults.
"Evidence is building up that something in relation to sunlight and/or vitamin D exposure during childhood may play a protective role," said study co-author Dr. Thomas M. Mack, of the department of preventive medicine, Keck School of Medicine, University of Southern California, Los Angeles. "It's now been suggested by several different studies that this is the case, and if it's true, it would be important."
The study is published in the July 24 issue of Neurology.
The findings echo those of a recent Harvard School of Public Health study, released in December and published in the Journal of the American Medical Association. That study found that among 140 white men and women, those with the highest levels of sunlight-derived vitamin D were 62 percent less likely to have developed MS than those with the lowest levels. The finding was not replicated in a smaller patient pool of either blacks or Hispanics, however.
According to the National Multiple Sclerosis Society (NMSS), MS is an autoimmune disease of the central nervous system that currently affects more than 400,000 Americans. More than 2.5 million men and women worldwide suffer from the disorder.
While it is unclear what causes MS, the often-crippling disease is thought to develop when the body's own immune system begins attacking a fat and protein-laden substance called myelin that insulates nerve fibers.
Numbness, tingling, loss of coordination and balance, blindness, fatigue, and even paralysis can ensue, as normal communications between brain and body progressively collapse.
The majority of MS patients are first diagnosed between the ages of 20 and 50, and female patients outnumber males two-to-one.
In the study, Mack's team assessed the sun exposure of 79 pairs of identical twins in the United States and Canada, in which at least one twin in each pair had been diagnosed with MS.
Most of the twins were girls, and among those with MS, most had been diagnosed between the ages of 20 and 40.
Each subject was asked about his or her childhood history of outdoor activity, as well as that of the twin.
Time spent tanning, going to the beach, and playing team sports during childhood was also noted. No absolute sun exposure measurements were recorded. Rather, the authors assessed relative degrees of sun exposure between twins, based on personal recall.
All participants were also asked to reveal any history of childhood infections as well as smoking habits.
The result: The twin with MS usually had been exposed to less sun overall as a child than the twin without the disease, the researchers found.
They observed, however, that this protective effect was only apparent among female twins. The lack of evidence among male twins could simply be a function of the relatively small number of male-male twins included in the study, the researchers said.
The degree to which the risk for developing MS was reduced as a result of increased sun exposure ranged from 25 percent to 57 percent, depending on what activity the disease-free twin had engaged in.
For example, the researchers determined that non-MS twins who had spent more childhood time sun-tanning than their sibling had a nearly 50 percent reduced risk of developing MS as an adult.
It's not clear how sun exposure might protect against the illness. Ultraviolet rays might trigger a beneficial cellular immune response directly, or perhaps sunlight helps stave off the disease indirectly, by boosting vitamin D production.
To better understand the mystery behind sun exposure and its link to MS risk, the researchers said future sun-MS studies should be given "high priority."
"If it's true that sunlight is protective and/or vitamin D is protective, then there's one group of people who ought to think seriously about it, and that is young parents who have MS," noted Mack. "Because the likelihood that a child of a parent with MS will go on to get MS is 3 or 4 percent. Which is many, many times the likelihood that the average person could get MS."
"So, I think if I was a young parent, and I or my wife had MS, and I had a child, I would want to take every step I could take to prevent my child from getting the disease," added Mack. "But," he cautioned, "the problem is, of course, that we know that too much sunlight is the cause of melanoma. So, that's a dilemma. We want to give the child some exposure but not too much."
Dr. John Richert, executive vice president for research and clinical programs at the NMSS, which co-sponsored the study, said that "we all have to take note of" the new findings.
"This is one of a series of reports over the last couple of years that have at least indirectly implicated the role of sun exposure and vitamin D production with susceptibility to MS," he noted. "And this builds a stronger and stronger case that sun is one of the factors that can contribute to the development of MS."
Richert observed that MS in general is more common the farther away from the equator one lives, particularly during childhood, further supporting the sunlight-MS link.
However, he also agreed that too much sunlight brings its own risks.
"Certainly, in terms of relative risk -- skin cancer that can develop from sun exposure versus the potentially diminished risk for MS -- we don't have equations to really balance these," Richert stressed. "And there's a lot more work that still needs to be done before any kind of recommendations can be made about sun exposure or vitamin D intake."
More information
For additional information on risk factors for MS, visit the National Multiple Sclerosis Society.
"Evidence is building up that something in relation to sunlight and/or vitamin D exposure during childhood may play a protective role," said study co-author Dr. Thomas M. Mack, of the department of preventive medicine, Keck School of Medicine, University of Southern California, Los Angeles. "It's now been suggested by several different studies that this is the case, and if it's true, it would be important."
The study is published in the July 24 issue of Neurology.
The findings echo those of a recent Harvard School of Public Health study, released in December and published in the Journal of the American Medical Association. That study found that among 140 white men and women, those with the highest levels of sunlight-derived vitamin D were 62 percent less likely to have developed MS than those with the lowest levels. The finding was not replicated in a smaller patient pool of either blacks or Hispanics, however.
According to the National Multiple Sclerosis Society (NMSS), MS is an autoimmune disease of the central nervous system that currently affects more than 400,000 Americans. More than 2.5 million men and women worldwide suffer from the disorder.
While it is unclear what causes MS, the often-crippling disease is thought to develop when the body's own immune system begins attacking a fat and protein-laden substance called myelin that insulates nerve fibers.
Numbness, tingling, loss of coordination and balance, blindness, fatigue, and even paralysis can ensue, as normal communications between brain and body progressively collapse.
The majority of MS patients are first diagnosed between the ages of 20 and 50, and female patients outnumber males two-to-one.
In the study, Mack's team assessed the sun exposure of 79 pairs of identical twins in the United States and Canada, in which at least one twin in each pair had been diagnosed with MS.
Most of the twins were girls, and among those with MS, most had been diagnosed between the ages of 20 and 40.
Each subject was asked about his or her childhood history of outdoor activity, as well as that of the twin.
Time spent tanning, going to the beach, and playing team sports during childhood was also noted. No absolute sun exposure measurements were recorded. Rather, the authors assessed relative degrees of sun exposure between twins, based on personal recall.
All participants were also asked to reveal any history of childhood infections as well as smoking habits.
The result: The twin with MS usually had been exposed to less sun overall as a child than the twin without the disease, the researchers found.
They observed, however, that this protective effect was only apparent among female twins. The lack of evidence among male twins could simply be a function of the relatively small number of male-male twins included in the study, the researchers said.
The degree to which the risk for developing MS was reduced as a result of increased sun exposure ranged from 25 percent to 57 percent, depending on what activity the disease-free twin had engaged in.
For example, the researchers determined that non-MS twins who had spent more childhood time sun-tanning than their sibling had a nearly 50 percent reduced risk of developing MS as an adult.
It's not clear how sun exposure might protect against the illness. Ultraviolet rays might trigger a beneficial cellular immune response directly, or perhaps sunlight helps stave off the disease indirectly, by boosting vitamin D production.
To better understand the mystery behind sun exposure and its link to MS risk, the researchers said future sun-MS studies should be given "high priority."
"If it's true that sunlight is protective and/or vitamin D is protective, then there's one group of people who ought to think seriously about it, and that is young parents who have MS," noted Mack. "Because the likelihood that a child of a parent with MS will go on to get MS is 3 or 4 percent. Which is many, many times the likelihood that the average person could get MS."
"So, I think if I was a young parent, and I or my wife had MS, and I had a child, I would want to take every step I could take to prevent my child from getting the disease," added Mack. "But," he cautioned, "the problem is, of course, that we know that too much sunlight is the cause of melanoma. So, that's a dilemma. We want to give the child some exposure but not too much."
Dr. John Richert, executive vice president for research and clinical programs at the NMSS, which co-sponsored the study, said that "we all have to take note of" the new findings.
"This is one of a series of reports over the last couple of years that have at least indirectly implicated the role of sun exposure and vitamin D production with susceptibility to MS," he noted. "And this builds a stronger and stronger case that sun is one of the factors that can contribute to the development of MS."
Richert observed that MS in general is more common the farther away from the equator one lives, particularly during childhood, further supporting the sunlight-MS link.
However, he also agreed that too much sunlight brings its own risks.
"Certainly, in terms of relative risk -- skin cancer that can develop from sun exposure versus the potentially diminished risk for MS -- we don't have equations to really balance these," Richert stressed. "And there's a lot more work that still needs to be done before any kind of recommendations can be made about sun exposure or vitamin D intake."
More information
For additional information on risk factors for MS, visit the National Multiple Sclerosis Society.
Agent Orange linked to blood pressure
WASHINGTON - Exposure to Agent Orange in Vietnam may lead to high blood pressure in some veterans, but the evidence is limited and only suggestive, the Institute of Medicine said Friday.
The IOM, an arm of the National Academy of Sciences, has been studying the effects of the herbicide Agent Orange on veterans since the early 1990s, and is issuing its seventh update.
Two recent studies of Vietnam veterans who handled Agent Orange and other defoliants indicated that these veterans have higher rates of high blood pressure, the report said.
Hypertension affects more than 70 million American adults and is a major risk factor for heart attack and stroke.
The new findings were consistent with other studies that looked at the health effects of herbicides. However, a new environmental study and an earlier study of workers in a herbicide manufacturing plant did not find evidence of an association between herbicide or dioxin exposure and increased high blood pressure.
Because of the inconsistent results the institute said the evidence is suggestive of, but insufficient to conclude with certainty, that exposure to the herbicide leads to high blood pressure.
The new update also said there is suggestive but limited evidence that AL amyloidosis is associated with herbicide exposure.
A rare condition that affects one person in 100,000, AL amyloidosis is characterized by the accumulation of protein deposits in and around organs.
The committee said AL amyloidosis shares many biological and pathological similarities with multiple myeloma and certain B-cell lymphomas, which have previously been found to be associated with exposure to herbicides.
___
On the Net:
Institute of Medicine: http://www.nationalacademies.org/iom
The IOM, an arm of the National Academy of Sciences, has been studying the effects of the herbicide Agent Orange on veterans since the early 1990s, and is issuing its seventh update.
Two recent studies of Vietnam veterans who handled Agent Orange and other defoliants indicated that these veterans have higher rates of high blood pressure, the report said.
Hypertension affects more than 70 million American adults and is a major risk factor for heart attack and stroke.
The new findings were consistent with other studies that looked at the health effects of herbicides. However, a new environmental study and an earlier study of workers in a herbicide manufacturing plant did not find evidence of an association between herbicide or dioxin exposure and increased high blood pressure.
Because of the inconsistent results the institute said the evidence is suggestive of, but insufficient to conclude with certainty, that exposure to the herbicide leads to high blood pressure.
The new update also said there is suggestive but limited evidence that AL amyloidosis is associated with herbicide exposure.
A rare condition that affects one person in 100,000, AL amyloidosis is characterized by the accumulation of protein deposits in and around organs.
The committee said AL amyloidosis shares many biological and pathological similarities with multiple myeloma and certain B-cell lymphomas, which have previously been found to be associated with exposure to herbicides.
___
On the Net:
Institute of Medicine: http://www.nationalacademies.org/iom
Monday, July 23, 2007
Study Links Diet Soft Drinks With Cardiac Risk
MONDAY, July 23 (HealthDay News) -- Drinking more than one soda a day -- even if it's the sugar-free diet kind -- is associated with an increased incidence of metabolic syndrome, a cluster of risk factors linked to the development of diabetes and cardiovascular disease, a study finds.
The link to diet soda found in the study was "striking" but not entirely a surprise, said Dr. Ramachandran Vasan, study senior author and professor of medicine at Boston University School of Medicine. There had been some hints of it in earlier studies, he said.
"But this is the first study to show the association in a prospective fashion and in a large population," Vasan said.
That population consisted of more than 6,000 participants in the Framingham Heart Study, which has been following residents of a Massachusetts town since 1948. When the soda portion of the study began, all participants were free of metabolic syndrome, a collection of risk factors including high blood pressure, elevated levels of the blood fats called triglycerides, low levels of the artery-protecting HDL cholesterol, high fasting blood sugar levels and excessive waist circumference. Metabolic syndrome is the presence of three or more of these risk factors.
Over the four years of the study, people who consumed more than one soft drink of any kind a day were 44 percent more likely to develop metabolic syndrome than those who didn't drink a soda a day.
The findings are published in the July 24 issue of the journal Circulation.
A variety of explanations, none proven, have been proposed for the link between diet soft drink consumption and metabolic syndrome, Vasan said. That association was evident even when the researchers accounted for other factors, such as levels of saturated fat and fiber in the diet, total calorie intake, smoking and physical activity.
One theory is that the high sweetness of all soft drinks makes a person more prone to eat sugary, fattening foods. Another is that the caramel content of soft drinks promotes metabolic changes that lead to insulin resistance. "These are hotly debated by nutritional experts," Vasan said.
Vasan, who noted that he is not a nutritional expert, said he leans toward the theory that "this is a marker of dietary behavior" -- that people who like to drink sweet soda also like to eat the kind of foods that cardiac nutritionists warn against.
"But we cannot infer causality," Vasan said, meaning there is no proof that soda itself is the villain. "We have an association. Maybe it is a causal one or maybe it is a marker of something else."
Carefully controlled animal studies might resolve the cause-and-effect issue, he said.
Dr. Elizabeth G. Nabel, director of the U.S. National Heart, Lung, and Blood Institute, which funds the Framingham Heart Study, said in a prepared statement: "Other studies have shown that the extra calories and sugar in soft drinks contribute to weight gain, and therefore heart disease risk. This study echoes those findings by extending the link to all soft drinks and the metabolic syndrome."
Dr. Suzanne R. Steinbaum, director of Women and Heart Disease at Lenox Hill Hospital in New York City, said, "There is no safe way of eating junk food, just as we learned the lesson from trans fats and partially hydrogenated oils often found in fat-free or low-fat cookies. Diet soda does not protect us from the development of what we are trying to avoid by consuming it."
More information
Learn more about metabolic syndrome at the American Heart Association.
The link to diet soda found in the study was "striking" but not entirely a surprise, said Dr. Ramachandran Vasan, study senior author and professor of medicine at Boston University School of Medicine. There had been some hints of it in earlier studies, he said.
"But this is the first study to show the association in a prospective fashion and in a large population," Vasan said.
That population consisted of more than 6,000 participants in the Framingham Heart Study, which has been following residents of a Massachusetts town since 1948. When the soda portion of the study began, all participants were free of metabolic syndrome, a collection of risk factors including high blood pressure, elevated levels of the blood fats called triglycerides, low levels of the artery-protecting HDL cholesterol, high fasting blood sugar levels and excessive waist circumference. Metabolic syndrome is the presence of three or more of these risk factors.
Over the four years of the study, people who consumed more than one soft drink of any kind a day were 44 percent more likely to develop metabolic syndrome than those who didn't drink a soda a day.
The findings are published in the July 24 issue of the journal Circulation.
A variety of explanations, none proven, have been proposed for the link between diet soft drink consumption and metabolic syndrome, Vasan said. That association was evident even when the researchers accounted for other factors, such as levels of saturated fat and fiber in the diet, total calorie intake, smoking and physical activity.
One theory is that the high sweetness of all soft drinks makes a person more prone to eat sugary, fattening foods. Another is that the caramel content of soft drinks promotes metabolic changes that lead to insulin resistance. "These are hotly debated by nutritional experts," Vasan said.
Vasan, who noted that he is not a nutritional expert, said he leans toward the theory that "this is a marker of dietary behavior" -- that people who like to drink sweet soda also like to eat the kind of foods that cardiac nutritionists warn against.
"But we cannot infer causality," Vasan said, meaning there is no proof that soda itself is the villain. "We have an association. Maybe it is a causal one or maybe it is a marker of something else."
Carefully controlled animal studies might resolve the cause-and-effect issue, he said.
Dr. Elizabeth G. Nabel, director of the U.S. National Heart, Lung, and Blood Institute, which funds the Framingham Heart Study, said in a prepared statement: "Other studies have shown that the extra calories and sugar in soft drinks contribute to weight gain, and therefore heart disease risk. This study echoes those findings by extending the link to all soft drinks and the metabolic syndrome."
Dr. Suzanne R. Steinbaum, director of Women and Heart Disease at Lenox Hill Hospital in New York City, said, "There is no safe way of eating junk food, just as we learned the lesson from trans fats and partially hydrogenated oils often found in fat-free or low-fat cookies. Diet soda does not protect us from the development of what we are trying to avoid by consuming it."
More information
Learn more about metabolic syndrome at the American Heart Association.
Friday, July 20, 2007
Key to a long life -- less insulin in the brain
WASHINGTON (Reuters) - Good, old-fashioned diet and exercise might keep you young by reducing the action of insulin in the brain, researchers reported on Thursday.
They created mutant mice that over-ate, got fat and even had symptoms of diabetes, and yet lived 18 percent longer than normal lab mice. The secret: they lacked a certain key gene that affects insulin, the hormone that regulates glucose.
The genetic engineering mimicked the effects of eating less and exercising, the researchers report in the journal Science.
"This study provides a new explanation of why it's good to exercise and not eat too much," said Dr. Morris White, a Howard Hughes Medical Institute investigator at Children's Hospital in Boston who led the study.
The findings also raise questions about how desirable it is to use insulin to treat type 2 diabetes, said the researchers.
Doctors know that people who exercise regularly live longer on average. Researchers have also learned that putting animals on a strict diet makes them live longer, although this has not yet been shown to work in people.
So White's team sought to see if the two effects were linked. They looked at insulin, because both fasting and exercise make cells more insulin-sensitive, meaning they respond more efficiently to the effects of insulin.
They looked at the entire insulin pathway -- a series of actions in the cell that control the body's use of insulin.
White's team engineered mice that had no working copies of one of the genes involved in this pathway, called insulin receptor substrate 2, or Irs2.
BEST USE OF INSULIN
Mice with no copies of Irs2 had defective brains and diabetes. But mice with one working copy lived 18 percent longer than normal mice.
"What's more, the animals lived longer even though they had characteristics that should shorten their lives such as being overweight and having higher insulin levels in the blood," White said in a statement.
They were also more active than normal mice, and after eating, their brains had higher levels of a compound called superoxide dismutase, an antioxidant that protects cells from damage.
"Diet, exercise and lower weight keep your peripheral tissues sensitive to insulin," White said. That means the body needs to make less insulin.
"Since insulin turns on Irs2 in the brain, that means lower Irs2 activity, which we've linked to longer life span in the mouse," he said.
One obvious question is whether drugs can mimic the effects of having less Irs2, perhaps by interfering with its action. The researchers note that people who live to be 100 or more often have reduced insulin levels and their cells show better insulin sensitivity.
New diabetes drugs that increase insulin sensitivity may help, too, White said. But, he added: "The easiest way to keep insulin levels low in the brain is old-fashioned diet and exercise."
They created mutant mice that over-ate, got fat and even had symptoms of diabetes, and yet lived 18 percent longer than normal lab mice. The secret: they lacked a certain key gene that affects insulin, the hormone that regulates glucose.
The genetic engineering mimicked the effects of eating less and exercising, the researchers report in the journal Science.
"This study provides a new explanation of why it's good to exercise and not eat too much," said Dr. Morris White, a Howard Hughes Medical Institute investigator at Children's Hospital in Boston who led the study.
The findings also raise questions about how desirable it is to use insulin to treat type 2 diabetes, said the researchers.
Doctors know that people who exercise regularly live longer on average. Researchers have also learned that putting animals on a strict diet makes them live longer, although this has not yet been shown to work in people.
So White's team sought to see if the two effects were linked. They looked at insulin, because both fasting and exercise make cells more insulin-sensitive, meaning they respond more efficiently to the effects of insulin.
They looked at the entire insulin pathway -- a series of actions in the cell that control the body's use of insulin.
White's team engineered mice that had no working copies of one of the genes involved in this pathway, called insulin receptor substrate 2, or Irs2.
BEST USE OF INSULIN
Mice with no copies of Irs2 had defective brains and diabetes. But mice with one working copy lived 18 percent longer than normal mice.
"What's more, the animals lived longer even though they had characteristics that should shorten their lives such as being overweight and having higher insulin levels in the blood," White said in a statement.
They were also more active than normal mice, and after eating, their brains had higher levels of a compound called superoxide dismutase, an antioxidant that protects cells from damage.
"Diet, exercise and lower weight keep your peripheral tissues sensitive to insulin," White said. That means the body needs to make less insulin.
"Since insulin turns on Irs2 in the brain, that means lower Irs2 activity, which we've linked to longer life span in the mouse," he said.
One obvious question is whether drugs can mimic the effects of having less Irs2, perhaps by interfering with its action. The researchers note that people who live to be 100 or more often have reduced insulin levels and their cells show better insulin sensitivity.
New diabetes drugs that increase insulin sensitivity may help, too, White said. But, he added: "The easiest way to keep insulin levels low in the brain is old-fashioned diet and exercise."
Tuesday, July 17, 2007
Fruits, veggies don't stop cancer return
CHICAGO - Hopes that a diet low in fat and chock-full of fruits and vegetables could prevent the return of breast cancer were dashed Tuesday by a large, seven-year experiment in more than 3,000 women.
The government study found no benefit from a mega-veggies-and-fruit diet over the U.S. recommended servings of five fruits and vegetables a day — more than most Americans get.
Researchers noted that none of the breast cancer survivors lost weight on either diet. That led some experts to suggest that weight loss and exercise should be the next frontier for cancer prevention research. The study appears in Wednesday's Journal of the American Medical Association.
"It sends us back to the drawing board," said Susan Gapstur of Northwestern University's Feinberg School of Medicine, who wasn't involved in the new study but co-wrote an accompanying editorial in the journal.
"Should we really have focused on dietary components like fruits, vegetables and fat?" Gapstur asked. "Or should we be focusing, in addition to diet, on lifestyle factors including physical activity and weight?"
For now, the message for the 2.4 million breast cancer survivors in the United States is that they don't need to go overboard on veggies, researchers said.
"This should really lift some of the guilt if women are feeling, 'I'm just not doing enough,'" said study co-author Marcia Stefanick of Stanford University.
The research was kicked off by a $5 million grant from the late Wal-Mart heir John Walton and got an additional $30 million in support from the National Cancer Institute.
Walton wanted to support a scientific study so cancer survivors wouldn't have to "rely on folklore," said John Pierce, head of cancer prevention at University of California, San Diego, who led the research.
Earlier research on whether a healthy diet prevents breast cancer has shown mixed results. The new study was designed to be more rigorous.
In this experiment, all the women had been successfully treated for early stage breast cancer. Their average age was 53 when the study began.
A group of 1,537 women were randomly assigned to a daily diet that included five vegetable servings, three fruit servings, 16 ounces of vegetable juice and 30 grams of fiber. In most cases, a serving equaled a half-cup. French fries and iceberg lettuce couldn't be counted as vegetables.
The women were allowed to eat meat, but were told to get no more than 15 percent to 20 percent of their calories from fat, a goal they ultimately were unable to achieve.
"That's a tough diet," said Pierce, who ate that way himself along with his staff and the women in the study.
As a comparison, another 1,551 women were assigned to get educational materials about the importance of eating five servings of fruits and vegetables a day.
The women in both groups kept food diaries regularly, but not daily, through the course of the study.
During the next seven years, the cancer returned in about the same proportion of women in both groups: 256 women (16.7 percent) of the women on the special diet and 262 women (16.9 percent) in the comparison group. About 10 percent of both groups died during that time, most of them from breast cancer.
It didn't matter whether the breast cancer was the most common type — fueled by hormones — or not; the special diet didn't prevent the cancer from coming back. Those results run counter to a previous study by different researchers that suggested low-fat diets may help prevent the return of the type of breast cancer that is not linked to hormones.
In the mega-veggies group, the women changed their eating habits substantially, mostly by increasing fruits and vegetables to as much as 11 servings a day. They failed to meet the fat target, but did eat 13 percent less in fat calories than did the comparison group.
After one year, women on the high-vegetable diet had 73 percent higher blood levels of carotenoids (pigments found in fruits and vegetables) than the other women. That indicates they were truthful about how many fruits and vegetables they ate, Pierce said.
But they may not have been so honest about the calories they ate. The super-veggie group gained 1.3 pounds and the comparison group gained 0.88 pound, on average.
"There's no question they were underreporting on calories, especially the heavier women," Pierce said, or they would have lost weight.
___
On the Net:
JAMA: http://jama.ama-assn.org
The government study found no benefit from a mega-veggies-and-fruit diet over the U.S. recommended servings of five fruits and vegetables a day — more than most Americans get.
Researchers noted that none of the breast cancer survivors lost weight on either diet. That led some experts to suggest that weight loss and exercise should be the next frontier for cancer prevention research. The study appears in Wednesday's Journal of the American Medical Association.
"It sends us back to the drawing board," said Susan Gapstur of Northwestern University's Feinberg School of Medicine, who wasn't involved in the new study but co-wrote an accompanying editorial in the journal.
"Should we really have focused on dietary components like fruits, vegetables and fat?" Gapstur asked. "Or should we be focusing, in addition to diet, on lifestyle factors including physical activity and weight?"
For now, the message for the 2.4 million breast cancer survivors in the United States is that they don't need to go overboard on veggies, researchers said.
"This should really lift some of the guilt if women are feeling, 'I'm just not doing enough,'" said study co-author Marcia Stefanick of Stanford University.
The research was kicked off by a $5 million grant from the late Wal-Mart heir John Walton and got an additional $30 million in support from the National Cancer Institute.
Walton wanted to support a scientific study so cancer survivors wouldn't have to "rely on folklore," said John Pierce, head of cancer prevention at University of California, San Diego, who led the research.
Earlier research on whether a healthy diet prevents breast cancer has shown mixed results. The new study was designed to be more rigorous.
In this experiment, all the women had been successfully treated for early stage breast cancer. Their average age was 53 when the study began.
A group of 1,537 women were randomly assigned to a daily diet that included five vegetable servings, three fruit servings, 16 ounces of vegetable juice and 30 grams of fiber. In most cases, a serving equaled a half-cup. French fries and iceberg lettuce couldn't be counted as vegetables.
The women were allowed to eat meat, but were told to get no more than 15 percent to 20 percent of their calories from fat, a goal they ultimately were unable to achieve.
"That's a tough diet," said Pierce, who ate that way himself along with his staff and the women in the study.
As a comparison, another 1,551 women were assigned to get educational materials about the importance of eating five servings of fruits and vegetables a day.
The women in both groups kept food diaries regularly, but not daily, through the course of the study.
During the next seven years, the cancer returned in about the same proportion of women in both groups: 256 women (16.7 percent) of the women on the special diet and 262 women (16.9 percent) in the comparison group. About 10 percent of both groups died during that time, most of them from breast cancer.
It didn't matter whether the breast cancer was the most common type — fueled by hormones — or not; the special diet didn't prevent the cancer from coming back. Those results run counter to a previous study by different researchers that suggested low-fat diets may help prevent the return of the type of breast cancer that is not linked to hormones.
In the mega-veggies group, the women changed their eating habits substantially, mostly by increasing fruits and vegetables to as much as 11 servings a day. They failed to meet the fat target, but did eat 13 percent less in fat calories than did the comparison group.
After one year, women on the high-vegetable diet had 73 percent higher blood levels of carotenoids (pigments found in fruits and vegetables) than the other women. That indicates they were truthful about how many fruits and vegetables they ate, Pierce said.
But they may not have been so honest about the calories they ate. The super-veggie group gained 1.3 pounds and the comparison group gained 0.88 pound, on average.
"There's no question they were underreporting on calories, especially the heavier women," Pierce said, or they would have lost weight.
___
On the Net:
JAMA: http://jama.ama-assn.org
Analysis: Older, cheaper diabetes drugs get high marks
Older, cheaper diabetes drugs are as safe and effective as newer ones, concludes an analysis that is good news for diabetics and may further hurt sales of Avandia, a blockbuster pill recently tied to heart problems.
Diabetes is epidemic, afflicting more than 18 million Americans or 7 percent of the population.
The clear winner: metformin, sold as Glucophage and generically for about $100 a year. It works as well as other diabetes pills but does not cause weight gain or too-low blood sugar, the analysis found. It also lowers LDL or bad cholesterol.
"It looks to be the safest," said Dr. Shari Bolen, a Johns Hopkins University researcher who led the review, which was published online Monday by the Annals of Internal Medicine.
Consumer Reports also published a consumer guide of the results. Besides metformin, it rates glipizide and glimepiride, sold as Amaryl and Glucotrol, as best bets.
"This is truly significant information for the millions of people with diabetes struggling to control their disease, but also struggling with the high cost of their medications," said Gail Shearer, project director of Consumer Reports Best Buy Drugs.
All diabetes pills can cause problems, so patients should pick the medication based on what side effects matter most in their own situation, the guide advises.
Diabetes is epidemic, afflicting more than 18 million Americans or 7 percent of the population. Most have Type 2, which occurs when the body makes too little insulin or cannot use what it does produce. Being overweight raises this risk.
The federal Agency for Healthcare Research and Quality commissioned the analysis of diabetes drugs in 2005, long before a study published in May suggested Avandia, made by GlaxoSmithKline PLC, raised the risk of heart attacks. The new analysis says that evidence is insufficient to settle this issue.
Don't Miss
Agency for Healthcare Research and Quality
Consumer Reports: BestBuy Drugs
The goal was to do the first in-depth comparison of oral medications that have come out in the last decade, as well as older ones like sulfonylureas that have been sold for 50 years. The report did not evaluate insulin or other injected diabetes drugs.
Researchers reviewed more than 200 published studies and obtained unpublished information from some drug companies and the federal Food and Drug Administration.
They found that most oral diabetes drugs lower "A1c" levels -- a key measure of high blood sugar -- by about one percentage point -- from 8 to 7, for example (5 is normal for non-diabetics).
Taking two medications can improve blood sugar control, but also costs more and can raise the risk of side effects.
Despite heavy marketing for newer drugs, which cost as much as $262 a month, "we didn't find any benefit" unless a patient could not tolerate an older one, Bolen said.
Other results:
• Metformin and acarbose (sold as Precose) do not increase weight. Others add 2 to 11 pounds.
• LDL or bad cholesterol drops by about 10 milligrams per deciliter of blood with metformin and increases by that amount with Avandia or Actos, made by Takeda Pharmaceuticals.
• Glimepiride, glipizide, glyburide and repaglinide lead to too-low blood sugar more often than other drugs do.
• Metformin and acarbose more often cause diarrhea and other digestive problems than the others.
• Actos and Avandia slightly raise HDL or good cholesterol.
• Actos and Avandia significantly raise the risk of heart failure.
Avandia's safety will be debated at an FDA hearing on July 30. GlaxoSmithKline says Avandia is safe but has not denied reports that sales have fallen about 30 percent since May 21, when a study linked it to heart attacks.
Don't Miss
MayoClinic.com: Diabetes
Healthology: Health Video Library
Company spokeswoman Mary Anne Rhyne said the analysis published Monday was done before one study had been completed that showed Avandia to better control blood sugar than two rival medications.
However, several diabetes specialists said the results are no surprise. The conclusions mirror those of an expert panel that leading U.S. and European diabetes groups convened last year, said Dr. David Nathan, diabetes chief at Massachusetts General Hospital. He has received speaker fees from several diabetes drug makers.
Metformin is "an incredibly inexpensive generic drug, which is why we found it so appealing," Nathan said.
But it can cause a rare but dangerous side effect called lactic acidosis, the buildup of lactic acid in the blood. It also should not be given to diabetics who have moderate kidney disease or heart failure. This is true of many other diabetes pills, too.
A key question is how well any of these drugs prevent long-term consequences, said Dr. Brian Strom, epidemiology chief at the University of Pennsylvania and a consultant to several diabetes drug makers.
"Part of what makes the Avandia question so important is it's been assumed that Avandia will decrease mortality" by better controlling blood sugar long-term -- not raise the risk of heart attacks or death, he said. Right now, "the data aren't there -- we don't know one way or another."
Diabetes is epidemic, afflicting more than 18 million Americans or 7 percent of the population.
The clear winner: metformin, sold as Glucophage and generically for about $100 a year. It works as well as other diabetes pills but does not cause weight gain or too-low blood sugar, the analysis found. It also lowers LDL or bad cholesterol.
"It looks to be the safest," said Dr. Shari Bolen, a Johns Hopkins University researcher who led the review, which was published online Monday by the Annals of Internal Medicine.
Consumer Reports also published a consumer guide of the results. Besides metformin, it rates glipizide and glimepiride, sold as Amaryl and Glucotrol, as best bets.
"This is truly significant information for the millions of people with diabetes struggling to control their disease, but also struggling with the high cost of their medications," said Gail Shearer, project director of Consumer Reports Best Buy Drugs.
All diabetes pills can cause problems, so patients should pick the medication based on what side effects matter most in their own situation, the guide advises.
Diabetes is epidemic, afflicting more than 18 million Americans or 7 percent of the population. Most have Type 2, which occurs when the body makes too little insulin or cannot use what it does produce. Being overweight raises this risk.
The federal Agency for Healthcare Research and Quality commissioned the analysis of diabetes drugs in 2005, long before a study published in May suggested Avandia, made by GlaxoSmithKline PLC, raised the risk of heart attacks. The new analysis says that evidence is insufficient to settle this issue.
Don't Miss
Agency for Healthcare Research and Quality
Consumer Reports: BestBuy Drugs
The goal was to do the first in-depth comparison of oral medications that have come out in the last decade, as well as older ones like sulfonylureas that have been sold for 50 years. The report did not evaluate insulin or other injected diabetes drugs.
Researchers reviewed more than 200 published studies and obtained unpublished information from some drug companies and the federal Food and Drug Administration.
They found that most oral diabetes drugs lower "A1c" levels -- a key measure of high blood sugar -- by about one percentage point -- from 8 to 7, for example (5 is normal for non-diabetics).
Taking two medications can improve blood sugar control, but also costs more and can raise the risk of side effects.
Despite heavy marketing for newer drugs, which cost as much as $262 a month, "we didn't find any benefit" unless a patient could not tolerate an older one, Bolen said.
Other results:
• Metformin and acarbose (sold as Precose) do not increase weight. Others add 2 to 11 pounds.
• LDL or bad cholesterol drops by about 10 milligrams per deciliter of blood with metformin and increases by that amount with Avandia or Actos, made by Takeda Pharmaceuticals.
• Glimepiride, glipizide, glyburide and repaglinide lead to too-low blood sugar more often than other drugs do.
• Metformin and acarbose more often cause diarrhea and other digestive problems than the others.
• Actos and Avandia slightly raise HDL or good cholesterol.
• Actos and Avandia significantly raise the risk of heart failure.
Avandia's safety will be debated at an FDA hearing on July 30. GlaxoSmithKline says Avandia is safe but has not denied reports that sales have fallen about 30 percent since May 21, when a study linked it to heart attacks.
Don't Miss
MayoClinic.com: Diabetes
Healthology: Health Video Library
Company spokeswoman Mary Anne Rhyne said the analysis published Monday was done before one study had been completed that showed Avandia to better control blood sugar than two rival medications.
However, several diabetes specialists said the results are no surprise. The conclusions mirror those of an expert panel that leading U.S. and European diabetes groups convened last year, said Dr. David Nathan, diabetes chief at Massachusetts General Hospital. He has received speaker fees from several diabetes drug makers.
Metformin is "an incredibly inexpensive generic drug, which is why we found it so appealing," Nathan said.
But it can cause a rare but dangerous side effect called lactic acidosis, the buildup of lactic acid in the blood. It also should not be given to diabetics who have moderate kidney disease or heart failure. This is true of many other diabetes pills, too.
A key question is how well any of these drugs prevent long-term consequences, said Dr. Brian Strom, epidemiology chief at the University of Pennsylvania and a consultant to several diabetes drug makers.
"Part of what makes the Avandia question so important is it's been assumed that Avandia will decrease mortality" by better controlling blood sugar long-term -- not raise the risk of heart attacks or death, he said. Right now, "the data aren't there -- we don't know one way or another."
Monday, July 16, 2007
Can the right food cut cost of cancer pills?
CHICAGO (Reuters) - Taking advantage of the power of food to boost the effectiveness of drugs could sharply lower the cost of cancer treatments, U.S. researchers said on Monday.
"We can use drug interactions to our advantage," said Dr. Ezra Cohen, a cancer drug expert at the University of Chicago Cohen, whose work appears in the Journal of Clinical Oncology.
He and colleague Mark Ratain analyzed data from a recent clinical trial showing how food affected GlaxoSmithKline's new breast cancer pill Tykerb, known generically as lapatinib.
The drug is supposed to be taken on an empty stomach. But taking it after a full meal would boost the amount of the drug circulating in the body by 167 percent, and taking it after a high-fat meal would boost it by 325 percent, the researchers found.
That might allow patients to use 40 percent less to achieve the same effect as taking it on an empty stomach. At a cost of $2,900 a month, the change could save each patient, or insurers, $1,740 or more a month, the researchers said.
And washing it down with grapefruit juice might allow patients to use as much as 80 percent less, they said. That could reduce the recommended dosage from the current five, 250 mg pills on an empty stomach to just one pill with a full meal and grapefruit juice chaser, they said.
But the researchers hastened to say they are not recommending that patients try this on their own.
"The first word of caution is 'do not try this at home.' The last thing we want is to have patients take their drug with food or change the dose on their own," Cohen said in a telephone interview. "That could be potentially dangerous."
The point, he said, is that instead of looking at drug interactions with food as something to be avoided, researchers should seek ways to benefit from them.
Food sometimes enhances the effectiveness of drugs because some foods are broken down by the same processes that the liver uses to break down drugs. If liver enzymes are all busy working on the food, they are not available to break down as much of the drug, meaning it circulates for longer in the system.
Cohen and Ratain are currently studying the effect of grapefruit juice, which is known to delay the breakdown of many drugs, on Wyeth's immune suppressant drug sirolimus or Rapamune, but there are many possibilities.
"The list can go on and on in terms of the agents that could be favorably modified to reduce dose and perhaps specific side effects," Cohen said.
"We can use drug interactions to our advantage," said Dr. Ezra Cohen, a cancer drug expert at the University of Chicago Cohen, whose work appears in the Journal of Clinical Oncology.
He and colleague Mark Ratain analyzed data from a recent clinical trial showing how food affected GlaxoSmithKline's new breast cancer pill Tykerb, known generically as lapatinib.
The drug is supposed to be taken on an empty stomach. But taking it after a full meal would boost the amount of the drug circulating in the body by 167 percent, and taking it after a high-fat meal would boost it by 325 percent, the researchers found.
That might allow patients to use 40 percent less to achieve the same effect as taking it on an empty stomach. At a cost of $2,900 a month, the change could save each patient, or insurers, $1,740 or more a month, the researchers said.
And washing it down with grapefruit juice might allow patients to use as much as 80 percent less, they said. That could reduce the recommended dosage from the current five, 250 mg pills on an empty stomach to just one pill with a full meal and grapefruit juice chaser, they said.
But the researchers hastened to say they are not recommending that patients try this on their own.
"The first word of caution is 'do not try this at home.' The last thing we want is to have patients take their drug with food or change the dose on their own," Cohen said in a telephone interview. "That could be potentially dangerous."
The point, he said, is that instead of looking at drug interactions with food as something to be avoided, researchers should seek ways to benefit from them.
Food sometimes enhances the effectiveness of drugs because some foods are broken down by the same processes that the liver uses to break down drugs. If liver enzymes are all busy working on the food, they are not available to break down as much of the drug, meaning it circulates for longer in the system.
Cohen and Ratain are currently studying the effect of grapefruit juice, which is known to delay the breakdown of many drugs, on Wyeth's immune suppressant drug sirolimus or Rapamune, but there are many possibilities.
"The list can go on and on in terms of the agents that could be favorably modified to reduce dose and perhaps specific side effects," Cohen said.
Saturday, July 14, 2007
Inflammatory Genes Raise Lung Cancer Risk
WEDNESDAY, July 11 (HealthDay News) -- Changes in two genes that activate the immune system after tissue damage may increase lung cancer risk, researchers report.
The changes were found on the genes for interleukin 1A and 1B, two molecules that immune system cells secrete in response to infection or tissue damage. The changes may cause the body to overproduce the molecules, which could sustain the inflammatory effects of the damage.
Writing in the July issue of Cancer Research, the researchers observed a stronger effect of the genes in heavy tobacco smokers.
"Our findings help explain how heavy smoking, for example, combines with a genetic predisposition to create a besieged environment within the lungs," lead author Dr. Eric Engels, researcher at the Viral Epidemiology Branch of the U.S. National Cancer Institute's Division of Cancer Epidemiology and Genetics, said in a prepared statement. "Essentially, sustained inflammation alters the microenvironment of the lung tissue, damaging cells and altering DNA."
The study is the first to pinpoint the mechanism by which damage to the lung might cause an inflammatory response from the immune system, leading to cancer. Inflammation is a normal part of the immune system's response to the effects of infection and cell damage, but the researchers argue that prolonged inflammation could increase the risk of lung cancer.
The team examined differences in genes related to inflammation among more than 1,500 lung cancer patients and 1,700 healthy adults. More than 80 percent of the lung cancer patients were former or current smokers.
The researchers then analyzed 59 variations on 37 inflammation-related genes. They found variants in the genes for interleukin 1A and 1B more frequently in patients with lung cancer, especially among heavy smokers.
More Americans die from lung cancer each year than any other type of cancer. In 2003, the most recent year for which data is available, 105,508 men and 84,789 women were diagnosed with lung cancer, while 89,906 men and 68,084 women died from the disease.
More information
To learn about lung cancer, visit the Centers for Disease Control and Prevention.
The changes were found on the genes for interleukin 1A and 1B, two molecules that immune system cells secrete in response to infection or tissue damage. The changes may cause the body to overproduce the molecules, which could sustain the inflammatory effects of the damage.
Writing in the July issue of Cancer Research, the researchers observed a stronger effect of the genes in heavy tobacco smokers.
"Our findings help explain how heavy smoking, for example, combines with a genetic predisposition to create a besieged environment within the lungs," lead author Dr. Eric Engels, researcher at the Viral Epidemiology Branch of the U.S. National Cancer Institute's Division of Cancer Epidemiology and Genetics, said in a prepared statement. "Essentially, sustained inflammation alters the microenvironment of the lung tissue, damaging cells and altering DNA."
The study is the first to pinpoint the mechanism by which damage to the lung might cause an inflammatory response from the immune system, leading to cancer. Inflammation is a normal part of the immune system's response to the effects of infection and cell damage, but the researchers argue that prolonged inflammation could increase the risk of lung cancer.
The team examined differences in genes related to inflammation among more than 1,500 lung cancer patients and 1,700 healthy adults. More than 80 percent of the lung cancer patients were former or current smokers.
The researchers then analyzed 59 variations on 37 inflammation-related genes. They found variants in the genes for interleukin 1A and 1B more frequently in patients with lung cancer, especially among heavy smokers.
More Americans die from lung cancer each year than any other type of cancer. In 2003, the most recent year for which data is available, 105,508 men and 84,789 women were diagnosed with lung cancer, while 89,906 men and 68,084 women died from the disease.
More information
To learn about lung cancer, visit the Centers for Disease Control and Prevention.
Thursday, July 12, 2007
Diabetes drug side effect reports triple
In the month after a surprising analysis revealed possible heart risks from the blockbuster diabetes drug Avandia, reports of side effects to federal regulators tripled.
The sudden spike is a sign that doctors probably were unaware of the drug's possible role in their patients' heart problems and therefore may not have reported many such cases in the past, several experts said.
It also shows the flaws of the safety tracking system and suggests that a better one might have detected a potential problem before the drug had been on the market for eight years.
Avandia is used to control blood sugar, helping more than 6 million people worldwide manage Type 2 diabetes, the kind that is linked to obesity. These people already are at higher risk for heart attacks, so news that the drug might raise this risk by 43 percent was especially disturbing.
In the 35 days after May 21, when the New England Journal of Medicine published the analysis on the Internet, reports of heart attacks, deaths and hospitalizations leaped. The sharp rise in reports of heart problems appears in data obtained by The Associated Press through a Freedom of Information Act request to the federal Food and Drug Administration.
Only five heart attacks were reported in the 35 days before the study, compared with 90 in the same period afterward. Heart-related hospitalizations went from 11 to 126. The reports involve rosiglitazone, sold as Avandia and Avandamet.
Reporting a drug's side effects is voluntary, and only a crude indication rather than a scientific measure of how many problems patients are actually having. The FDA relies on this unenforced system once a drug is on the market. Critics say it leads to haphazard oversight in which problems can be missed because doctors don't connect the dots between a drug and symptoms they see in an individual patient.
With Avandia, the published analysis likely led to more cases being reported, said Vanderbilt University diabetes specialist Dr. Alvin C. Powers.
"Now, patients and their doctors are much more aware of the possible link between Avandia and cardiovascular disease. This is good — this is going to help us going forward to determine whether or not this drug is safe," he said.
The drug's manufacturer, British-based GlaxoSmithKline PLC, insists that the drug is safe and effective.
"This is a very well-known phenomenon," where news reports lead to increased reporting, said company spokeswoman Mary Anne Rhyne. "It's good that there's awareness of the reporting system, but drawing conclusions on such data is inappropriate."
The FDA plans hearings on safety concerns about the drug on July 30. In the meantime, diabetes experts have advised users of the medication to talk to their doctors and not to immediately discontinue it.
The side effects reported range from as minor as a blister to as serious as sudden cardiac death. Most of the reports the AP reviewed seemed to involve serious side effects, and rosiglitazone was listed by the FDA as the "primary suspect" rather than other medicines the patient may have been taking.
There was a total of only 50 adverse event reports in January and 73 in February. From April 16 to May 21, when the study was published, 121 events were reported, including 11 deaths. In the 35 days after the study, 357 events were reported, including 38 deaths.
"You really can't infer anything about incidence rates from that," because the spike in reports is likely due to the "publicity effect" of the study, said Dr. David Graham, an FDA drug safety expert.
Dr. David Nathan, chief of diabetes care at Massachusetts General Hospital, agreed, saying it was "not conceivable" that only five people among the 1 million Americans taking Avandia had heart attacks in the month preceding the May 21 study, as the FDA reports suggest.
"It just heightens the concern about the poor reporting we have," said Nathan, who has received speaker fees from Glaxo and other drug companies. Powers and Graham have no financial ties to any diabetes drug makers.
The issue has roiled the medical community and sparked congressional probes into whether the FDA is properly investigating safety issues. The FDA issued a "safety alert" about the drug only after the May 21 study came out, even though Glaxo had informed the agency of its own analysis of heart risks nearly a year beforehand and possibly as early as 2005.
Avandia's label warns about possible heart failure and other heart problems when taken with insulin. The drug also raises LDL, or bad cholesterol, and can cause fluid retention and weight gain.
___
On the Net:
GlaxoSmithKline: http://www.gsk.com
Food and Drug Administration: http:http://www.fda.gov
Avandia's label: http://tinyurl.com/2qzhfe
Diabetes information: http://www.diabetes.org
and http://diabetes.niddk.nih.gov/
The sudden spike is a sign that doctors probably were unaware of the drug's possible role in their patients' heart problems and therefore may not have reported many such cases in the past, several experts said.
It also shows the flaws of the safety tracking system and suggests that a better one might have detected a potential problem before the drug had been on the market for eight years.
Avandia is used to control blood sugar, helping more than 6 million people worldwide manage Type 2 diabetes, the kind that is linked to obesity. These people already are at higher risk for heart attacks, so news that the drug might raise this risk by 43 percent was especially disturbing.
In the 35 days after May 21, when the New England Journal of Medicine published the analysis on the Internet, reports of heart attacks, deaths and hospitalizations leaped. The sharp rise in reports of heart problems appears in data obtained by The Associated Press through a Freedom of Information Act request to the federal Food and Drug Administration.
Only five heart attacks were reported in the 35 days before the study, compared with 90 in the same period afterward. Heart-related hospitalizations went from 11 to 126. The reports involve rosiglitazone, sold as Avandia and Avandamet.
Reporting a drug's side effects is voluntary, and only a crude indication rather than a scientific measure of how many problems patients are actually having. The FDA relies on this unenforced system once a drug is on the market. Critics say it leads to haphazard oversight in which problems can be missed because doctors don't connect the dots between a drug and symptoms they see in an individual patient.
With Avandia, the published analysis likely led to more cases being reported, said Vanderbilt University diabetes specialist Dr. Alvin C. Powers.
"Now, patients and their doctors are much more aware of the possible link between Avandia and cardiovascular disease. This is good — this is going to help us going forward to determine whether or not this drug is safe," he said.
The drug's manufacturer, British-based GlaxoSmithKline PLC, insists that the drug is safe and effective.
"This is a very well-known phenomenon," where news reports lead to increased reporting, said company spokeswoman Mary Anne Rhyne. "It's good that there's awareness of the reporting system, but drawing conclusions on such data is inappropriate."
The FDA plans hearings on safety concerns about the drug on July 30. In the meantime, diabetes experts have advised users of the medication to talk to their doctors and not to immediately discontinue it.
The side effects reported range from as minor as a blister to as serious as sudden cardiac death. Most of the reports the AP reviewed seemed to involve serious side effects, and rosiglitazone was listed by the FDA as the "primary suspect" rather than other medicines the patient may have been taking.
There was a total of only 50 adverse event reports in January and 73 in February. From April 16 to May 21, when the study was published, 121 events were reported, including 11 deaths. In the 35 days after the study, 357 events were reported, including 38 deaths.
"You really can't infer anything about incidence rates from that," because the spike in reports is likely due to the "publicity effect" of the study, said Dr. David Graham, an FDA drug safety expert.
Dr. David Nathan, chief of diabetes care at Massachusetts General Hospital, agreed, saying it was "not conceivable" that only five people among the 1 million Americans taking Avandia had heart attacks in the month preceding the May 21 study, as the FDA reports suggest.
"It just heightens the concern about the poor reporting we have," said Nathan, who has received speaker fees from Glaxo and other drug companies. Powers and Graham have no financial ties to any diabetes drug makers.
The issue has roiled the medical community and sparked congressional probes into whether the FDA is properly investigating safety issues. The FDA issued a "safety alert" about the drug only after the May 21 study came out, even though Glaxo had informed the agency of its own analysis of heart risks nearly a year beforehand and possibly as early as 2005.
Avandia's label warns about possible heart failure and other heart problems when taken with insulin. The drug also raises LDL, or bad cholesterol, and can cause fluid retention and weight gain.
___
On the Net:
GlaxoSmithKline: http://www.gsk.com
Food and Drug Administration: http:http://www.fda.gov
Avandia's label: http://tinyurl.com/2qzhfe
Diabetes information: http://www.diabetes.org
and http://diabetes.niddk.nih.gov/
Wednesday, July 11, 2007
Meats, Sweets May Boost Breast Cancer Risk
TUESDAY, July 10 (HealthDay News) -- A study of older Chinese women suggests that a move toward a Western-style diet -- heavy on meat and sugary foods -- boosts breast cancer risk.
Postmenopausal Chinese women who ate a diet that included red meat, starches and sweets were twice as likely to develop breast cancer than those who ate the traditional vegetable-soy-fish diet, according to a study in the July issue of the journal Cancer Epidemiology, Biomarkers & Prevention.
In the study, American and Chinese researchers studied women, ages 25 to 64, in Shanghai who were newly diagnosed with breast cancer between August 1996 and March 1998.
The dietary habits of the women with the 1,602 breast cancer cases were compared to those of more than 1,500 women without breast cancer.
The researchers found that overweight, postmenopausal women who ate a western-style diet had a greater than twofold increased risk of estrogen-receptor-positive breast cancers. There was no association between breast cancer risk and a vegetable-soy-fish diet.
The "meat-sweet" western diet relies on various kinds of meats, saltwater fish and shellfish, bread, milk, dessert and candy. The vegetable-soy-fish diet favors various vegetables, soy-based products, and freshwater fish.
"The Shanghai data gave us a unique look at a population of Chinese women who were beginning to adopt more western-style eating habits," researcher Marilyn Tseng, an associate member in the population science division at Fox Chase Cancer Center in Philadelphia, said in a prepared statement.
"Our study suggests the possibility that the 'meat-sweet' pattern interacts with obesity to increase breast cancer risk," Tseng said. "Low consumption of a western dietary pattern plus successful weight control may protect against breast cancer in a traditionally low-risk Asian population that is poised to more broadly adopt foods characteristic of western societies."
More information
Breastcancer.org has more about nutrition and breast cancer.
Postmenopausal Chinese women who ate a diet that included red meat, starches and sweets were twice as likely to develop breast cancer than those who ate the traditional vegetable-soy-fish diet, according to a study in the July issue of the journal Cancer Epidemiology, Biomarkers & Prevention.
In the study, American and Chinese researchers studied women, ages 25 to 64, in Shanghai who were newly diagnosed with breast cancer between August 1996 and March 1998.
The dietary habits of the women with the 1,602 breast cancer cases were compared to those of more than 1,500 women without breast cancer.
The researchers found that overweight, postmenopausal women who ate a western-style diet had a greater than twofold increased risk of estrogen-receptor-positive breast cancers. There was no association between breast cancer risk and a vegetable-soy-fish diet.
The "meat-sweet" western diet relies on various kinds of meats, saltwater fish and shellfish, bread, milk, dessert and candy. The vegetable-soy-fish diet favors various vegetables, soy-based products, and freshwater fish.
"The Shanghai data gave us a unique look at a population of Chinese women who were beginning to adopt more western-style eating habits," researcher Marilyn Tseng, an associate member in the population science division at Fox Chase Cancer Center in Philadelphia, said in a prepared statement.
"Our study suggests the possibility that the 'meat-sweet' pattern interacts with obesity to increase breast cancer risk," Tseng said. "Low consumption of a western dietary pattern plus successful weight control may protect against breast cancer in a traditionally low-risk Asian population that is poised to more broadly adopt foods characteristic of western societies."
More information
Breastcancer.org has more about nutrition and breast cancer.
Tuesday, July 10, 2007
No Evidence Tomatoes, Lycopene Cut Cancer: FDA
TUESDAY, July 10 (HealthDay News) -- There's little hard evidence that a diet rich in tomatoes and the tomato antioxidant lycopene can ward off cancer, according to research from the U.S. Food and Drug Administration.
Reporting in the July 10 issue of the Journal of the American Cancer Institute, FDA experts lay out in great detail the evidence -- or mostly lack of it -- behind their November 2005 statement that tomato consumption is not linked to any reduction risk of tumors of the prostate, ovary, stomach and pancreas.
The agency had previously found no evidence that tomatoes could cut risks for lung, colorectal, breast, cervical or endometrial tumors, either.
The November 2005 statement contended that, "there is no credible evidence to support qualified health claims for lycopene, as a food ingredient, component or food, or as a dietary supplement, and reduced risk of any of the cancers in the petition."
The petition for approval of the claims was submitted by a supplement maker, American Longevity.
The FDA has now put the evidence behind its decision in print, said Paul Coates, director of the office of dietary supplements at the U.S. National Institutes of Health and the author of a related journal editorial.
The new data review "gives people some idea of what the process is," Coates said. That's important, he said, because "one of the things that people are concerned about is how are these decisions arrived at. Making the process transparent and open will be helpful."
As part of its review, the FDA pored over data from 107 observational studies comparing the level of consumption of either tomatoes or lycopene with people's general cancer risk. They also looked at 23 studies that focused on blood levels of lycopene, although most of those trials were deemed unreliable, either because there were too many confounding factors or because most focused on cancer patients, not healthy people.
The agency also included dozens of studies comparing lycopene or tomato intake against the risk of individual cancers such as prostate, colon and breast malignancies.
The bottom line, according to the FDA: There's just not enough evidence to recommend that Americans boost their tomato intake to ward off cancer.
However, the new report is certainly not the last word on cancer-preventing claims for lycopene, Coates added.
"It just codifies the fact that the information about lycopene and cancer is not very robust," he said. "It may well be that if more studies are done, a greater effect might be found. But now, when you look at similar studies done by different people, they come to the same conclusion."
For its part, the American Cancer Society prefers to stay away from recommending any one food as a cancer preventive agent, said Marji McCullough, director of nutritional epidemiology for the organization.
"In our guidelines, we encourage people to eat a variety of foods, especially fruits and vegetables," she said. "Several studies have suggested a lower risk of cancer with some kinds of foods, including tomatoes, but we encourage variety."
The society encourages consumption of "dark deep-colored vegetables, because some studies have found an association between them and lower cancer risk," McCullough said.
The society also encourages fruit and vegetable consumption, because it helps prevent weight gain, she said.
But endorsement of specific foods won't come until research shows that they clearly are associated with lower cancer risk, McCullough said. As for supplements, "most of the evidence comes from studies of foods," she said.
More information
There's more on lycopene at the American Cancer Society.
Reporting in the July 10 issue of the Journal of the American Cancer Institute, FDA experts lay out in great detail the evidence -- or mostly lack of it -- behind their November 2005 statement that tomato consumption is not linked to any reduction risk of tumors of the prostate, ovary, stomach and pancreas.
The agency had previously found no evidence that tomatoes could cut risks for lung, colorectal, breast, cervical or endometrial tumors, either.
The November 2005 statement contended that, "there is no credible evidence to support qualified health claims for lycopene, as a food ingredient, component or food, or as a dietary supplement, and reduced risk of any of the cancers in the petition."
The petition for approval of the claims was submitted by a supplement maker, American Longevity.
The FDA has now put the evidence behind its decision in print, said Paul Coates, director of the office of dietary supplements at the U.S. National Institutes of Health and the author of a related journal editorial.
The new data review "gives people some idea of what the process is," Coates said. That's important, he said, because "one of the things that people are concerned about is how are these decisions arrived at. Making the process transparent and open will be helpful."
As part of its review, the FDA pored over data from 107 observational studies comparing the level of consumption of either tomatoes or lycopene with people's general cancer risk. They also looked at 23 studies that focused on blood levels of lycopene, although most of those trials were deemed unreliable, either because there were too many confounding factors or because most focused on cancer patients, not healthy people.
The agency also included dozens of studies comparing lycopene or tomato intake against the risk of individual cancers such as prostate, colon and breast malignancies.
The bottom line, according to the FDA: There's just not enough evidence to recommend that Americans boost their tomato intake to ward off cancer.
However, the new report is certainly not the last word on cancer-preventing claims for lycopene, Coates added.
"It just codifies the fact that the information about lycopene and cancer is not very robust," he said. "It may well be that if more studies are done, a greater effect might be found. But now, when you look at similar studies done by different people, they come to the same conclusion."
For its part, the American Cancer Society prefers to stay away from recommending any one food as a cancer preventive agent, said Marji McCullough, director of nutritional epidemiology for the organization.
"In our guidelines, we encourage people to eat a variety of foods, especially fruits and vegetables," she said. "Several studies have suggested a lower risk of cancer with some kinds of foods, including tomatoes, but we encourage variety."
The society encourages consumption of "dark deep-colored vegetables, because some studies have found an association between them and lower cancer risk," McCullough said.
The society also encourages fruit and vegetable consumption, because it helps prevent weight gain, she said.
But endorsement of specific foods won't come until research shows that they clearly are associated with lower cancer risk, McCullough said. As for supplements, "most of the evidence comes from studies of foods," she said.
More information
There's more on lycopene at the American Cancer Society.
Tuesday, July 3, 2007
New Drug Deletes Bad Memories
Do you have a really bad memory, or past heartache, that you would prefer to forget?
Researchers at Harvard and McGill University (in Montreal) are working on an amnesia drug that blocks or deletes bad memories. The technique seems to allow psychiatrists to disrupt the biochemical pathways that allow a memory to be recalled.
In a new study, published in the Journal of Psychiatric Research, the drug propranolol is used along with therapy to "dampen" memories of trauma victims. They treated 19 accident or rape victims for ten days, during which the patients were asked to describe their memories of the traumatic event that had happened 10 years earlier. Some patients were given the drug, which is also used to treat amnesia, while others were given a placebo.
A week later, they found that patients given the drug showed fewer signs of stress when recalling their trauma.
Similar research led by Professor Joseph LeDoux has been carried out at New York University on rats; scientists were able to remove a specific memory from the brains of rats while leaving the rest of the animals' memories intact. An amnesia drug called U0126 was administered.
The rats were trained to associate two musical tones with a mild electrical shock so that when they heard either of the tones they would brace themselves for a shock. The researchers then gave half the rats the drug when playing one of the musical tones.
After the treatment, the rats that had been given the drug no longer associated that particular tone with an imminent shock but still braced themselves upon hearing the second tone, demonstrating only one memory had been deleted.
Science fiction fans have a number of associations with the idea of banishing unwanted memories. In the 2004 film Eternal Sunshine of the Spotless Mind, Kate Winslet and Jim Carrey play lovers who have a falling out. Winslet's character goes to a company called Lacuna, Inc. to have her memories of the relationship removed; Carrey's character also has the procedure performed (see photo).
In the film, the process involves showing the person a memento of the relationship and then encouraging them to bring up specific memories while an electric shock is given. Not to give away the film, but this technique does not work as planned.
Here's a memory you might have repressed. In the classic Star Trek episode Requiem for Methuselah, Jim Kirk becomes enamored of Rayna, a beautiful woman who turns out to be an android created by a five thousand year old man who calls himself Flint, who was also Leonardo DaVinci and Shakespeare (among many others) during the course of his long life. Flint wants Rayna for himself, Kirk wants her, she loves them both, her circuits overload resulting in her death, and Kirk is devastated.
Finally, Spock saves the day by applying a little-known property of the Vulcan mind-meld, which is that he can make Kirk forget about his sorrows and return to duty (see touching photo).
Science fiction legend Philip K. Dick was one of the first to make use of this idea. In his 1966 short story We Can Remember It For You Wholesale he writes about selectively erasing memories:
Someone, probably at a government military-sciences lab, erased his conscious memories; all he know was that going to Mars meant something special to him, and so did being a secret agent...
Read more about erasing memories. Read more about "Scientists find drug to banish bad memories." Thanks to Technovelgy reader Miez who contributed this story.
(This Science Fiction in the News story used with permission from Technovelgy.com - where science meets fiction.)
Researchers at Harvard and McGill University (in Montreal) are working on an amnesia drug that blocks or deletes bad memories. The technique seems to allow psychiatrists to disrupt the biochemical pathways that allow a memory to be recalled.
In a new study, published in the Journal of Psychiatric Research, the drug propranolol is used along with therapy to "dampen" memories of trauma victims. They treated 19 accident or rape victims for ten days, during which the patients were asked to describe their memories of the traumatic event that had happened 10 years earlier. Some patients were given the drug, which is also used to treat amnesia, while others were given a placebo.
A week later, they found that patients given the drug showed fewer signs of stress when recalling their trauma.
Similar research led by Professor Joseph LeDoux has been carried out at New York University on rats; scientists were able to remove a specific memory from the brains of rats while leaving the rest of the animals' memories intact. An amnesia drug called U0126 was administered.
The rats were trained to associate two musical tones with a mild electrical shock so that when they heard either of the tones they would brace themselves for a shock. The researchers then gave half the rats the drug when playing one of the musical tones.
After the treatment, the rats that had been given the drug no longer associated that particular tone with an imminent shock but still braced themselves upon hearing the second tone, demonstrating only one memory had been deleted.
Science fiction fans have a number of associations with the idea of banishing unwanted memories. In the 2004 film Eternal Sunshine of the Spotless Mind, Kate Winslet and Jim Carrey play lovers who have a falling out. Winslet's character goes to a company called Lacuna, Inc. to have her memories of the relationship removed; Carrey's character also has the procedure performed (see photo).
In the film, the process involves showing the person a memento of the relationship and then encouraging them to bring up specific memories while an electric shock is given. Not to give away the film, but this technique does not work as planned.
Here's a memory you might have repressed. In the classic Star Trek episode Requiem for Methuselah, Jim Kirk becomes enamored of Rayna, a beautiful woman who turns out to be an android created by a five thousand year old man who calls himself Flint, who was also Leonardo DaVinci and Shakespeare (among many others) during the course of his long life. Flint wants Rayna for himself, Kirk wants her, she loves them both, her circuits overload resulting in her death, and Kirk is devastated.
Finally, Spock saves the day by applying a little-known property of the Vulcan mind-meld, which is that he can make Kirk forget about his sorrows and return to duty (see touching photo).
Science fiction legend Philip K. Dick was one of the first to make use of this idea. In his 1966 short story We Can Remember It For You Wholesale he writes about selectively erasing memories:
Someone, probably at a government military-sciences lab, erased his conscious memories; all he know was that going to Mars meant something special to him, and so did being a secret agent...
Read more about erasing memories. Read more about "Scientists find drug to banish bad memories." Thanks to Technovelgy reader Miez who contributed this story.
(This Science Fiction in the News story used with permission from Technovelgy.com - where science meets fiction.)
Monday, July 2, 2007
Poor sense of smell may be Alzheimer's
CHICAGO - Difficulty identifying common smells such as lemon, banana and cinnamon may be the first sign of Alzheimer's disease, according to a study that could lead to scratch-and-sniff tests to determine a person's risk for the progressive brain disorder.
Such tests could be important if scientists find ways to slow or stop Alzheimer's and the severe memory loss associated with it. For now, there's no cure for the more than 5 million Americans with the disease.
Researchers have long known that microscopic lesions considered the hallmarks of Alzheimer's first appear in a brain region important to the sense of smell.
"Strictly on the basis of anatomy, yeah, this makes sense," said Robert Franks, an expert on odor perception and the brain at the University of Cincinnati. Franks was not involved in the new study, appearing in Monday's Archives of General Psychiatry.
Other studies have linked loss of smell to Alzheimer's, Franks said, but this is the first to measure healthy people's olfactory powers and follow them for five years, testing along the way for signs of mental decline.
In the study, 600 people between the ages of 54 and 100 were asked to identify a dozen familiar smells: onion, lemon, cinnamon, black pepper, chocolate, rose, banana, pineapple, soap, paint thinner, gasoline and smoke.
For each mystery scent, they heard and saw a choice of four answers. For cinnamon, they were asked aloud: "Fruit? Cinnamon? Woody? Or coconut?" while also seeing the choices in text.
A quarter of the people correctly identified all the odors or missed only one. Half of them knew at least nine of the 12. The lowest-scoring quarter of the people correctly identified eight or fewer of the odors.
The subjects took 21 cognitive tests annually over the next five years. About one-third of the people developed at least mild trouble with memory and thinking.
The people who made at least four errors on the odor test were 50 percent more likely to develop problems than people who made no more than one error. Difficulty identifying odors also was associated with a higher risk of progressing from mild cognitive impairment to Alzheimer's.
The researchers took into account age, gender, education and a history of strokes or smoking, and still found lower scores predicted higher risk of cognitive decline.
Lead author Robert Wilson of Chicago's Rush University Medical Center said a diminishing sense of smell isn't cause for panic.
"Not all low scorers went on to have cognitive problems," Wilson said.
Older people should report a loss in smell to their doctors, said Claire Murphy, an Alzheimer's researcher at San Diego State University who was not involved in the new study. The problem could be caused by a polyp in the nose or infected sinuses, she said.
"If a person is old and has a very good sense of smell, that's a very good sign," Murphy said.
The study was funded by the National Institute on Aging and the Illinois Department of Public Health.
Such tests could be important if scientists find ways to slow or stop Alzheimer's and the severe memory loss associated with it. For now, there's no cure for the more than 5 million Americans with the disease.
Researchers have long known that microscopic lesions considered the hallmarks of Alzheimer's first appear in a brain region important to the sense of smell.
"Strictly on the basis of anatomy, yeah, this makes sense," said Robert Franks, an expert on odor perception and the brain at the University of Cincinnati. Franks was not involved in the new study, appearing in Monday's Archives of General Psychiatry.
Other studies have linked loss of smell to Alzheimer's, Franks said, but this is the first to measure healthy people's olfactory powers and follow them for five years, testing along the way for signs of mental decline.
In the study, 600 people between the ages of 54 and 100 were asked to identify a dozen familiar smells: onion, lemon, cinnamon, black pepper, chocolate, rose, banana, pineapple, soap, paint thinner, gasoline and smoke.
For each mystery scent, they heard and saw a choice of four answers. For cinnamon, they were asked aloud: "Fruit? Cinnamon? Woody? Or coconut?" while also seeing the choices in text.
A quarter of the people correctly identified all the odors or missed only one. Half of them knew at least nine of the 12. The lowest-scoring quarter of the people correctly identified eight or fewer of the odors.
The subjects took 21 cognitive tests annually over the next five years. About one-third of the people developed at least mild trouble with memory and thinking.
The people who made at least four errors on the odor test were 50 percent more likely to develop problems than people who made no more than one error. Difficulty identifying odors also was associated with a higher risk of progressing from mild cognitive impairment to Alzheimer's.
The researchers took into account age, gender, education and a history of strokes or smoking, and still found lower scores predicted higher risk of cognitive decline.
Lead author Robert Wilson of Chicago's Rush University Medical Center said a diminishing sense of smell isn't cause for panic.
"Not all low scorers went on to have cognitive problems," Wilson said.
Older people should report a loss in smell to their doctors, said Claire Murphy, an Alzheimer's researcher at San Diego State University who was not involved in the new study. The problem could be caused by a polyp in the nose or infected sinuses, she said.
"If a person is old and has a very good sense of smell, that's a very good sign," Murphy said.
The study was funded by the National Institute on Aging and the Illinois Department of Public Health.
Survey finds U.S. hospital, doctor visits balloon
WASHINGTON (Reuters) - Hospital and doctor visits in the United States have surged by 20 percent in the past five years and the most commonly prescribed medications are antidepressants, according to statistics published on Friday.
The survey by the U.S. Centers for Disease Control and Prevention also found most people who visited emergency rooms had private health insurance, although the uninsured were twice as likely to use emergency services as people with insurance.
The report estimates that 1.2 billion visits were made to hospitals, emergency rooms and physicians' offices in 2005.
"It was only a few years ago that we released that the total number of visits had reached 1 billion. And now we are up to 1.2 billion," Catharine Burt of the CDC's National Center for Health Statistics said in a telephone interview.
"That's a 20 percent increase in the just the last five years -- a huge number," said Burt. "I can tell you that the number of hospitals and physicians has not increased 20 percent."
The reason is clear -- Americans are getting older. "When you reach 50 things start going wrong, just little by little, and you keep going back to the doctors," Burt said.
The baby boom generation -- born between 1946 and 1964 -- are now prime users of the medical system.
Burt's team surveyed 352 hospitals and about 1,200 physicians throughout 2005 for the study.
OLDER AND DEPRESSED
Of 2.4 billion drugs mentioned in patients' medical records in 2005, 118 million were antidepressants, Burt found. High blood pressure drugs followed, with 113 million and arthritis or headache drugs were mentioned in 110 million.
"These are visits. These aren't people," she said. People taking antidepressants may need more frequent doctor visits.
The report also shed light on the controversial issue of emergency room visits. Many health care experts are worried that the 43 million people who lack health insurance in the United States must rely on emergency rooms for care -- not the best way to prevent serious conditions.
The survey suggests this is true. "People with no insurance are twice as likely to use the emergency department as the privately insured," Burt said.
Nearly 28 percent of all doctors visits by uninsured people are to emergency rooms, compared to 6.6 percent of visits made by people with insurance.
The report found that 46 million of the visits made to ERs in 2005 were by people with insurance, compared to 19 million by people without insurance.
"With 315,000 people visiting emergency departments every day, the alarm bells are sounding and policymakers should heed the alert and respond," said Dr. Brian Keaton, president of the American College of Emergency Physicians, which is pressing for a national commission on access to emergency medical services.
The CDC report is available on the Internet at http://www.cdc.gov/nchs/data/ad/ad388.pdf.
The survey by the U.S. Centers for Disease Control and Prevention also found most people who visited emergency rooms had private health insurance, although the uninsured were twice as likely to use emergency services as people with insurance.
The report estimates that 1.2 billion visits were made to hospitals, emergency rooms and physicians' offices in 2005.
"It was only a few years ago that we released that the total number of visits had reached 1 billion. And now we are up to 1.2 billion," Catharine Burt of the CDC's National Center for Health Statistics said in a telephone interview.
"That's a 20 percent increase in the just the last five years -- a huge number," said Burt. "I can tell you that the number of hospitals and physicians has not increased 20 percent."
The reason is clear -- Americans are getting older. "When you reach 50 things start going wrong, just little by little, and you keep going back to the doctors," Burt said.
The baby boom generation -- born between 1946 and 1964 -- are now prime users of the medical system.
Burt's team surveyed 352 hospitals and about 1,200 physicians throughout 2005 for the study.
OLDER AND DEPRESSED
Of 2.4 billion drugs mentioned in patients' medical records in 2005, 118 million were antidepressants, Burt found. High blood pressure drugs followed, with 113 million and arthritis or headache drugs were mentioned in 110 million.
"These are visits. These aren't people," she said. People taking antidepressants may need more frequent doctor visits.
The report also shed light on the controversial issue of emergency room visits. Many health care experts are worried that the 43 million people who lack health insurance in the United States must rely on emergency rooms for care -- not the best way to prevent serious conditions.
The survey suggests this is true. "People with no insurance are twice as likely to use the emergency department as the privately insured," Burt said.
Nearly 28 percent of all doctors visits by uninsured people are to emergency rooms, compared to 6.6 percent of visits made by people with insurance.
The report found that 46 million of the visits made to ERs in 2005 were by people with insurance, compared to 19 million by people without insurance.
"With 315,000 people visiting emergency departments every day, the alarm bells are sounding and policymakers should heed the alert and respond," said Dr. Brian Keaton, president of the American College of Emergency Physicians, which is pressing for a national commission on access to emergency medical services.
The CDC report is available on the Internet at http://www.cdc.gov/nchs/data/ad/ad388.pdf.
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