(HealthDay News) -- Being in good physical form appears to protect middle-aged and older men and women from stroke, a new British study suggests.
The finding highlights an apparent association -- rather than a direct cause-and-effect -- between the physical ability to function well and a reduced risk for stroke.
After sifting through thousands of quality-of-life reports provided by patients themselves, the research team found that those functioning at the higher end of the physical capacity spectrum appear to have half the risk for stroke as their poorest functioning compatriots, independent of other risk factors.
"We were surprised at the magnitude of the relationship, as this is comparable to established stroke risk factors such as smoking," noted study author Dr. Phyo Kyaw Myint, who works with the Clinical Gerontology Unit at Addenbrooke's University Hospital in Cambridge.
The findings are published in the Dec. 11 issue of Neurology.
Myint and his colleagues uncovered an apparent stroke-physical function connection by analyzing data concerning more than 13,600 British men and women between the ages of 40 and 79.
All the participants first completed a health examination and questionnaire between 1993 and 1997. At that time, patient blood pressure, body-mass index, respiratory capacity, and cholesterol levels were assessed. Researchers also noted any history of diabetes, smoking and alcohol consumption.
None of the patients had experienced any incidence of cancer, stroke or heart attack before their initial exam.
Eighteen months after the initial exam, patients completed a follow-up questionnaire by mail, in which patients were asked to indicate their degree of physical and social functioning; their mental health status; any physical and/or emotional limitations on carrying out routines; energy levels; experiences of pain; and self-perceptions regarding their overall health.
All participants were followed until 2005, by which point 244 strokes were recorded.
The researchers found that those men and women who reported better physical function had a considerably lower risk for stroke.
After adjusting for all other observed characteristics -- including gender and age -- Myint and his team found that patients in the top quarter of physical function capacity had half the risk of stroke when compared with patients in the lowest quarter of physical function.
The authors concluded that poor physical function could indicate a high risk for stroke, thereby highlighting a specific segment of the general population that could derive particular benefit from some form of intervention.
Myint stressed, however, that to date his team has simply conducted a hands-off review of patient self-reports regarding their physical capacity and lined those reports up against stroke incidence records. At no time were patients assessed for their ability to follow a prescribed physical activity routine of varying intensities and durations.
He cautioned against leaping to the notion that greater physical function or activity directly causes a drop in the risk for stroke.
"We don't know whether physical function per se is causally related to stroke or simply a good marker for other factors that influence stroke risk," Myint noted. "These findings need confirmation from other studies. However, there is already a substantial body of evidence for public health recommendations to increase physical activity."
In the meantime, Alice H. Lichtenstein, director of the Cardiovascular Nutrition Lab at Tufts University in Boston, said that people should not sit idly by while investigators continue to unravel the complex web of factors related to stroke risk.
"This study does not show causation, but clearly, individuals who follow current guidelines for decreasing risk for stroke and general cardiovascular risk -- including keeping physically active -- have better outcomes," she said. "So, in terms of both physical function and activity, what people need to try to do is go from where they are to more."
"For some people, doing more may literally mean just walking around the block once, or picking up the pace, or adding extra time moving," said Lichtenstein. "For others, it can even be something like doing the housecleaning. And it can be cumulative: 10 minutes at one point, 10 minutes at another. Because although we'd like everyone to set aside special time just for physical activity every day, we know that for a lot of people, it's just not going to happen. So, any increase is going in the right direction, and that should be the goal."
This week, the American Society for Nutrition is poised to issue a new set of national recommendations regarding both physical activity and nutrition.
The recommendations are described as "comprehensive, scientific guidelines on physical activity for all Americans." According to the U.S. Department of Health and Human Services, the guidelines will gather together the latest knowledge on both healthy eating and regular physical activity.
More information
To learn about stroke risk, visit the American Heart Association.
Selasa, 11 Desember 2007
Kamis, 06 Desember 2007
Common Household Chemical Could Raise Breast Cancer Risk
(HealthDay News) -- A chemical found in many plastic products used in households caused accelerated breast development and genetic changes in newborn female lab rats, a condition that might predispose the animals to breast cancer later in life, a new study says.
Butyl benzyl phthalate (BBP) is commonly used to soften polymers and plastics. It's found in everything from plastic pipes, vinyl floor tiles and carpet backing to lipstick. BBP has also been found to be an endocrine disruptor, which mimics the effect of hormones. Endocrine disruptors are known to damage wildlife and have also been implicated in reduced sperm counts and neurological problems in humans, the researchers said.
"Our study is the first one demonstrating that exposure to this compound (BBP) soon after birth results in alterations in the expression of genes present in the mammary gland," said lead researcher Dr. Jose Russo, a breast cancer expert at the Fox Chase Cancer Center, in Philadelphia.
The findings are important, Russo said, because the researchers are studying the lifetime effect of BBP on the mammary gland, long before it starts developing under the influence of the hormones of puberty, and the potential implications on humans.
Because of lasting genetic changes in the breast, exposure to BBP could increase the risk for developing breast cancer later in life, Russo said.
"To prevent breast cancer in adulthood, it is necessary to protect both the newborn child and the mother from exposure to this compound that has an estrogenic effect and could act as an endocrine disruptor," he added.
For the study, Russo's team fed lactating rats BBP, which their offspring absorbed through breast milk. The rat pups received levels of the chemical equivalent to the U.S. Environmental Protection Agency's safe dose limit for humans, according to the report in the Dec. 5 online issue of BMC Genomics.
The researchers found that BBP affected characteristics of the female offspring of the rats, such as more rapid breast development and changes in the genetic profile of the mammary glands.
While these effects wore off after exposure to BBP was stopped, the changes caused by the chemical might have an effect later in life, the researchers said.
"Our original observations are that the genomic changes induced by BBP occur very early in life, and they could result in significant modifications in the risk of the mammary gland to develop cancer later on in life," Russo said.
Russo said he and his colleagues are currently evaluating how changes in gene expression caused by BBP respond to cancer-causing chemicals given to adult rats.
"We are also studying the effects of exposure to BBP before birth. In addition, we are following a cohort of girls entering puberty for determining the tempo of breast development and their first menstrual period and associating these events with exposure to environmental agents such as BBP," Russo said.
One expert said scientists are only beginning to learn how many genes are affected by exposure to chemicals early in life.
"The early exposure to BBP altered breast development and may therefore alter the susceptibility to breast cancer," said Dr. Ted Schettler, science director at the Science and Environmental Health Network, in Ames, Iowa.
Schettler thinks people need to be aware of the possible effects of chemicals on genes during early life, and how these changes can influence susceptibility to disease in adulthood.
"People are finally getting the idea that early life events can matter later in life," Schettler said.
"When people see that commonly encountered environmental agents like BBP can cause genetic changes, it's of public health interest."
However, Dr. Jonathan Borak, a clinical professor of environmental medicine at Yale University School of Public Health, said there's no evidence that exposure to BBP increases the risk of breast cancer.
"To date, studies have failed to find an association between BBP and breast cancer," Borak said. "This study doesn't add specific information on breast cancer and environmental interactions."
Efforts to reach the American Chemistry Council, a chemical industry group, for comment on the study were unsuccessful.
In October, California adopted a law that will ban trace amounts of BBP in toys and baby products such as teething rings, according to published reports.
And in March, a study published in the journal Environmental Health Perspectives suggested that exposure to phthalates could be fueling the obesity epidemic by contributing to abdominal obesity and insulin resistance in men.
More information
For more on breast cancer, visit the American Cancer Society.
Butyl benzyl phthalate (BBP) is commonly used to soften polymers and plastics. It's found in everything from plastic pipes, vinyl floor tiles and carpet backing to lipstick. BBP has also been found to be an endocrine disruptor, which mimics the effect of hormones. Endocrine disruptors are known to damage wildlife and have also been implicated in reduced sperm counts and neurological problems in humans, the researchers said.
"Our study is the first one demonstrating that exposure to this compound (BBP) soon after birth results in alterations in the expression of genes present in the mammary gland," said lead researcher Dr. Jose Russo, a breast cancer expert at the Fox Chase Cancer Center, in Philadelphia.
The findings are important, Russo said, because the researchers are studying the lifetime effect of BBP on the mammary gland, long before it starts developing under the influence of the hormones of puberty, and the potential implications on humans.
Because of lasting genetic changes in the breast, exposure to BBP could increase the risk for developing breast cancer later in life, Russo said.
"To prevent breast cancer in adulthood, it is necessary to protect both the newborn child and the mother from exposure to this compound that has an estrogenic effect and could act as an endocrine disruptor," he added.
For the study, Russo's team fed lactating rats BBP, which their offspring absorbed through breast milk. The rat pups received levels of the chemical equivalent to the U.S. Environmental Protection Agency's safe dose limit for humans, according to the report in the Dec. 5 online issue of BMC Genomics.
The researchers found that BBP affected characteristics of the female offspring of the rats, such as more rapid breast development and changes in the genetic profile of the mammary glands.
While these effects wore off after exposure to BBP was stopped, the changes caused by the chemical might have an effect later in life, the researchers said.
"Our original observations are that the genomic changes induced by BBP occur very early in life, and they could result in significant modifications in the risk of the mammary gland to develop cancer later on in life," Russo said.
Russo said he and his colleagues are currently evaluating how changes in gene expression caused by BBP respond to cancer-causing chemicals given to adult rats.
"We are also studying the effects of exposure to BBP before birth. In addition, we are following a cohort of girls entering puberty for determining the tempo of breast development and their first menstrual period and associating these events with exposure to environmental agents such as BBP," Russo said.
One expert said scientists are only beginning to learn how many genes are affected by exposure to chemicals early in life.
"The early exposure to BBP altered breast development and may therefore alter the susceptibility to breast cancer," said Dr. Ted Schettler, science director at the Science and Environmental Health Network, in Ames, Iowa.
Schettler thinks people need to be aware of the possible effects of chemicals on genes during early life, and how these changes can influence susceptibility to disease in adulthood.
"People are finally getting the idea that early life events can matter later in life," Schettler said.
"When people see that commonly encountered environmental agents like BBP can cause genetic changes, it's of public health interest."
However, Dr. Jonathan Borak, a clinical professor of environmental medicine at Yale University School of Public Health, said there's no evidence that exposure to BBP increases the risk of breast cancer.
"To date, studies have failed to find an association between BBP and breast cancer," Borak said. "This study doesn't add specific information on breast cancer and environmental interactions."
Efforts to reach the American Chemistry Council, a chemical industry group, for comment on the study were unsuccessful.
In October, California adopted a law that will ban trace amounts of BBP in toys and baby products such as teething rings, according to published reports.
And in March, a study published in the journal Environmental Health Perspectives suggested that exposure to phthalates could be fueling the obesity epidemic by contributing to abdominal obesity and insulin resistance in men.
More information
For more on breast cancer, visit the American Cancer Society.
Sabtu, 01 Desember 2007
FDA Report Says Nation's Health at Risk
(HealthDay News) -- A new report by a U.S. Food and Drug Administration subcommittee says the agency can no longer adequately protect the nation's food and drug supply.
The Subcommittee on Science and Technology lays the blame squarely on inadequate funding, which it says has not kept pace with increasing demands on the agency.
"This imbalance is imposing a significant risk to the integrity of the food, drug, cosmetic and device regulatory system, and hence the safety of the public," the report states.
And things could get worse, the report stresses: "...the Agency suffers from serious scientific deficiencies and is not positioned to meet current or emerging regulatory responsibilities."
William Hubbard, a former FDA associate commissioner and an advisor to the Coalition for a Stronger FDA, a group that lobbies on behalf of the agency, called the report "one of the most remarkable reports I've ever seen. They are basically saying the FDA can't protect the public, and they are saying that our future competitiveness in new technology, emerging science and pharmaceuticals and devices is seriously threatened."
Hubbard also thinks that more money is needed for the FDA to do its job. "The number doesn't matter -- it just needs to be a lot," he said. "You would need a steady increase over five years to fix the FDA."
The report started as a review of the science at the FDA, Hubbard said, and mushroomed into something more.
"The committee was horrified that the science wasn't there, then they were horrified that the capabilities weren't there -- and the only way to fix that is funding," he said.
The FDA budget request for 2008 is $1.74 billion, plus another $444 million in user fees. These fees are paid by drug makers and medical device makers to underwrite the approval process of their products.
Another expert thinks that the FDA needs more money, but to really protect the public the agency's culture also needs changing.
"You need not only an overhaul of resources but an overhaul of philosophy on what safety and efficacy really means," said Dr. A. Mark Fendrick, a professor of internal medicine and professor of health management and policy at the University of Michigan.
"While a substantial increase in resources will enhance the scientific capabilities and capacity of the FDA, funding alone will not address the inherent tension between America's insatiable demand for immediate access for innovative products and an unwillingness to tolerate products that are anything but perfectly safe," Fendrick explained.
Another FDA supporter also thinks that improving the FDA starts with money.
"There are a lot of problems in the FDA that can't be solved without more resources," said Steven Grossman, a spokesman for the FDA Alliance, which lobbies on behalf of the agency. "All the problems don't go away if you have more money, but there are a whole lot of problems you can't confront without money."
Grossman thinks there is need for another $450 million in unrestricted spending to start bringing the agency up to snuff. That request is currently winding its way through Congress. "We hope to get at least a third of that," he said. It's going to take several years of increased funding to get the FDA to where it should be, he added.
According to the report, the FDA's "inability to keep up with scientific advances means that American lives are at risk." The committee noted that while science had undergone radical changes, the agency' evaluation methods haven't hanged in more than 50 years.
In addition, the food supply is at risk, the report said: "Crisis management in [the] FDA's two food safety centers, [the] Center for Food Safety and Applied Nutrition (CFSAN) and [the] Center for Veterinary Medicine (CVM), has drawn attention and resources away from FDA's ability to develop the science base and infrastructure needed to efficiently support innovation in the food industry, provide effective routine surveillance, and conduct emergency outbreak investigation activities to protect the food supply."
The report also calls for better-trained FDA scientists and improvements in the agency's computer technology. The full report will be presented at a meeting of the FDA's Science Board on Monday.
In recent years, numerous food recalls and the withdrawal from the market of popular medications -- the removal of the painkiller Vioxx in 2004 was one of the most high-profile examples -- have eroded public confidence in the FDA. A recent survey found that 47 percent of Americans rated its performance as fair or poor.
And a study published in September found the number of serious adverse drug events more than doubled between 1998 and 2005 in the United States, as did the number of related deaths. From 1998 to 2005, the number of reported serious adverse drug events increased from 34,966 to 89,842. The number of fatal adverse drug events almost tripled during the same time period, from 5,519 in 1998 to 15,107 in 2005.
The number of adverse events increased four times faster than the total number of outpatient prescriptions, which rose from 2.7 billion to 3.8 billion during that time frame, according to the study, which was published in the Archives of Internal Medicine.
Dr. Sidney M. Wolfe, director of Public Citizen's Health Research Group, called the new FDA report a "partial and simplistic view of what is wrong with the FDA."
"There seems to be more importance placed on satisfying industry [at the FDA]. It's not an atmosphere where people are free to express their differing opinions," he said.
Wolfe thinks the agency needs to be changed substantially, including new legislation that would strengthen its ability to regulate food additives, drugs and dietary supplements. He also thinks user fees should be abolished, because the fees make the relationship between the agency and drug companies too close.
More information
For more on what the FDA is doing about drug safety, visit the Food and Drug Administration.
more discussion: Forum
· Addiction Forum · Ask the Doctors Forum · Ayurveda Forum · Ayurvedic & Thai Herbs Forum · Colon Cleansing Forum · Dental Forum · Diabetes Forum · Diet Forum · General Cleansing Forum · Hepatitis A, B. C Forum · Integrated Medicine Forum · Live Blood Analysis Forum · Ozone-Oxygen-Forum · pH - Alkaline - Acidity Forum · Weight Loss Forum
The Subcommittee on Science and Technology lays the blame squarely on inadequate funding, which it says has not kept pace with increasing demands on the agency.
"This imbalance is imposing a significant risk to the integrity of the food, drug, cosmetic and device regulatory system, and hence the safety of the public," the report states.
And things could get worse, the report stresses: "...the Agency suffers from serious scientific deficiencies and is not positioned to meet current or emerging regulatory responsibilities."
William Hubbard, a former FDA associate commissioner and an advisor to the Coalition for a Stronger FDA, a group that lobbies on behalf of the agency, called the report "one of the most remarkable reports I've ever seen. They are basically saying the FDA can't protect the public, and they are saying that our future competitiveness in new technology, emerging science and pharmaceuticals and devices is seriously threatened."
Hubbard also thinks that more money is needed for the FDA to do its job. "The number doesn't matter -- it just needs to be a lot," he said. "You would need a steady increase over five years to fix the FDA."
The report started as a review of the science at the FDA, Hubbard said, and mushroomed into something more.
"The committee was horrified that the science wasn't there, then they were horrified that the capabilities weren't there -- and the only way to fix that is funding," he said.
The FDA budget request for 2008 is $1.74 billion, plus another $444 million in user fees. These fees are paid by drug makers and medical device makers to underwrite the approval process of their products.
Another expert thinks that the FDA needs more money, but to really protect the public the agency's culture also needs changing.
"You need not only an overhaul of resources but an overhaul of philosophy on what safety and efficacy really means," said Dr. A. Mark Fendrick, a professor of internal medicine and professor of health management and policy at the University of Michigan.
"While a substantial increase in resources will enhance the scientific capabilities and capacity of the FDA, funding alone will not address the inherent tension between America's insatiable demand for immediate access for innovative products and an unwillingness to tolerate products that are anything but perfectly safe," Fendrick explained.
Another FDA supporter also thinks that improving the FDA starts with money.
"There are a lot of problems in the FDA that can't be solved without more resources," said Steven Grossman, a spokesman for the FDA Alliance, which lobbies on behalf of the agency. "All the problems don't go away if you have more money, but there are a whole lot of problems you can't confront without money."
Grossman thinks there is need for another $450 million in unrestricted spending to start bringing the agency up to snuff. That request is currently winding its way through Congress. "We hope to get at least a third of that," he said. It's going to take several years of increased funding to get the FDA to where it should be, he added.
According to the report, the FDA's "inability to keep up with scientific advances means that American lives are at risk." The committee noted that while science had undergone radical changes, the agency' evaluation methods haven't hanged in more than 50 years.
In addition, the food supply is at risk, the report said: "Crisis management in [the] FDA's two food safety centers, [the] Center for Food Safety and Applied Nutrition (CFSAN) and [the] Center for Veterinary Medicine (CVM), has drawn attention and resources away from FDA's ability to develop the science base and infrastructure needed to efficiently support innovation in the food industry, provide effective routine surveillance, and conduct emergency outbreak investigation activities to protect the food supply."
The report also calls for better-trained FDA scientists and improvements in the agency's computer technology. The full report will be presented at a meeting of the FDA's Science Board on Monday.
In recent years, numerous food recalls and the withdrawal from the market of popular medications -- the removal of the painkiller Vioxx in 2004 was one of the most high-profile examples -- have eroded public confidence in the FDA. A recent survey found that 47 percent of Americans rated its performance as fair or poor.
And a study published in September found the number of serious adverse drug events more than doubled between 1998 and 2005 in the United States, as did the number of related deaths. From 1998 to 2005, the number of reported serious adverse drug events increased from 34,966 to 89,842. The number of fatal adverse drug events almost tripled during the same time period, from 5,519 in 1998 to 15,107 in 2005.
The number of adverse events increased four times faster than the total number of outpatient prescriptions, which rose from 2.7 billion to 3.8 billion during that time frame, according to the study, which was published in the Archives of Internal Medicine.
Dr. Sidney M. Wolfe, director of Public Citizen's Health Research Group, called the new FDA report a "partial and simplistic view of what is wrong with the FDA."
"There seems to be more importance placed on satisfying industry [at the FDA]. It's not an atmosphere where people are free to express their differing opinions," he said.
Wolfe thinks the agency needs to be changed substantially, including new legislation that would strengthen its ability to regulate food additives, drugs and dietary supplements. He also thinks user fees should be abolished, because the fees make the relationship between the agency and drug companies too close.
More information
For more on what the FDA is doing about drug safety, visit the Food and Drug Administration.
more discussion: Forum
· Addiction Forum · Ask the Doctors Forum · Ayurveda Forum · Ayurvedic & Thai Herbs Forum · Colon Cleansing Forum · Dental Forum · Diabetes Forum · Diet Forum · General Cleansing Forum · Hepatitis A, B. C Forum · Integrated Medicine Forum · Live Blood Analysis Forum · Ozone-Oxygen-Forum · pH - Alkaline - Acidity Forum · Weight Loss Forum
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