This edition of the RFE/RL Health Report features encouraging news about treatments for heart disease, new tools to help doctors and other health care professionals treat obese patients, and a UN study on some possible hidden dangers from air travel. Our correspondent K.P. Foley reports.
Walking May Lower Heart Disease Risk For Women
Washington, 23 March 2001 (RFE/RL) -- A team of researchers concludes that walking at least one hour per week may lower a woman's risk of heart disease. And, the researchers add, it makes no difference how fast or slow a woman walks.
The finding was published this week in the "Journal of the American Medical Association." This week's edition of the journal was devoted to women's health issues.
The study's leading author, I-Min Lee of the Brigham and Women's Hospital and Harvard Medical School in Boston, noted that coronary heart disease is the leading cause of death among women in the United States, and physical inactivity is among the risk factors for this disease.
Lee told a Washington press conference this week that the good news is that even limited amounts of physical activity benefit the heart.
"The bottom line of this paper is that, really, even very small amounts of physical activity can be beneficial to women with regards to lowering their risk of heart disease."
Lee stressed that there is a lot of evidence that exercise can cut the risk of heart disease. However, she said that what she and her fellow researchers wanted to find out was just how strenuous that exercise ought to be.
"While it is clear that exercise in the generic sense is associated with lower rates of heart disease in women, what is less clear are the kinds of intensities of activities that women should be doing. There are few data especially in women."
For the study, the authors looked at more than 39,000 healthy women aged 45 and up. The women reported how much time they spent each week on recreational activities, including walking and stair climbing. The authors computed energy expended by the women and measured the correlation of heart disease with energy expended.
The study followed the women for five years, and during that time, there were 244 confirmed incidents of heart disease. Lee said exercise cut the disease rate by 50 percent.
"We found that in these women, walking at least an hour a week reduced their risk of coronary heart disease by half, compared with women who were sedentary, who did not walk regularly."
Most important, she said, was the finding that, "the time that they spent walking was more important than the pace of walking."
(More details and other reports on women's health at http://jama.ama-assn.org/)
Doctors Encouraged By Tests Of Vessel Growth Drugs
Heart specialists say they are encouraged by test results of drugs designed to help the human body grow new blood vessels to do the work of veins and arteries clogged by plaque.
Results from two major drug studies were announced this week at the annual scientific session of the American College of Cardiology meeting in Orlando in the southern state of Florida.
Blocked arteries, a condition called atherosclerosis, can lead to heart attacks or strokes or recurring bouts of chest pain known as angina. When arteries supplying blood to the legs are blocked, the ailment is called Peripheral Artery Disease (PAD). PAD causes sharp pains in the legs that are brought on by exertion and relieved by rest. It's common among people over 55. Smokers and people with high levels of blood cholesterol are more prone to the condition.
Robert Lederman of the U.S. National Institutes of Health told reporters that PAD is a dangerous condition.
"Peripheral Artery Disease is another manifestation of the same disease, atherosclerosis, that causes myocardial infarction and agina, but now it's involving the lower extremities. And the mere presence of Peripheral Artery Disease, atherosclerosis, is a bad prognosticator for these patients."
Researchers have for several years been experimenting with genetically engineered drugs with the goal of finding a safe, reliable method for spurring blood vessel growth, a phenomenon called angiogenesis.
Lederman and several colleagues at Duke University and the University of Michigan reported on their studies of a protein called "fibroblast growth factor," or FGF-2. They injected this drug into the legs of patients who had trouble walking because of blocked arteries. The doctors compared this test group against another group of patients who received an injection of a placebo -- a harmless but unmedicated substance.
After 90 days, Lederman said the group that received FGF-2 showed significant improvement in exercise tests on a treadmill compared with the group that received the dummy injection. He said the findings are important because of the strict nature of the experiment.
"This is the first large, randomized, placebo-controlled therapeutic angiogenesis study to show that benefit in its primary efficacy measure."
In a second study presented at the Florida conference, doctors discussed results of a similar test conducted on heart patients suffering angina pains. This time, the growth factor substance was injected into the coronary arteries. The patients who received the growth factor injections did better on treadmill tests than patients who received a placebo.
The researchers stressed that more work, including larger studies, is needed before the drugs can be made available to the general public, but they said the tests indicate that angiogenesis is a promising heart and blood vessel disease treatment.
U.S. Offers Obesity Treatment Guide
The U.S. National Institutes of Health (NIH) has prepared what it calls a practical guide to help doctors, nurses, nutritionists, and others manage the treatment of overweight and obese patients. The clinical tools were developed by the NIH Heart, Lung and Blood division and they will be available on the Internet.
Heart, Lung and Blood Institute Director Claude Lenfant says 61 percent of American adults -- that's 108 million people -- are at risk of heart disease, stroke, diabetes, and cancer because of their weight. The guide is designed to help health care professionals evaluate and treat weight problems. The guide includes detailed sections on dietary therapy, physical activity, and behavior therapy. The NIH says it also discusses the use of drugs for weight loss and the use of surgery for treating obesity.
The guide has a section for patients too. That part includes practical advice on diet and exercise and behavior change programs.
(More information available at www.nhlbi.nih.gov)
UN Studying Link Between Air Travel, Blood Clots
United Nations experts say there probably is a connection between air travel and a potentially dangerous condition known as "deep vein thromobosis." The condition is also sometimes called "economy-class," or "coach-class syndrome."
Doctors say it most often develops after long air trips in cramped seats. The problem occurs when blood collects, or pools, in the legs and pelvis when a person remains seated for a long time. If the blood clots, a piece of the clot can break off and travel to the lungs, causing a potentially deadly condition called a pulmonary embolism.
The UN's World Health Organization convened an expert panel last week to review what is known about the condition. The experts said that while the potential for a dangerous blood clot can occur after a prolonged period of sitting, the link is likely to be small. The WHO panelists said the problem is most likely to develop in passengers with additional risk factors. These include a history of clotting problems in the legs, obesity, recent surgery or trauma, and genetic blood clotting difficulties.
The WHO reminded long distance passengers that common sense measures may go a long way toward preventing "economy-class syndrome." These measures include occasional breaks for walking and stretching, when possible, in the airplane's aisles, reducing or avoiding alcohol consumption, and wearing comfortable clothes.