MONDAY, Aug. 29, 2005 (HealthDayNews) -- No matter what their cholesterol level, men who are physically fit cut their risk of dying from heart disease by 50 percent, a new Canadian study finds.
"We should be promoting physical activity at all levels of risk," said lead researcher Peter T. Katzmarzyk, an associate professor in the School of Physical and Health Education at Queens University, in Kingston, Ontario.
The main objective of the study was to assess changes to guidelines from the National Cholesterol Education Program Adult Treatment Panel III (ATP). The guidelines are aimed at lowering LDL "bad" cholesterol and predicting risk for cardiovascular disease.
The report appears in the Aug. 30 online issue of Circulation.
"The guidelines that lay out targets for [HDL] 'good' cholesterol levels appear to work very well for predicting those who are at risk of dying prematurely from cardiovascular disease," Katzmarzyk noted.
In their study, Katzmarzyk's team collected data on more than 19,000 men, aged 20 to 79 years old, who attended a preventive medical clinic between 1979 and 1995.
Using the new ATP III classifications, 58 percent of the men would have met the criteria for being "at or below LDL cholesterol goal;" 18 percent would have been labeled as needing "therapeutic lifestyle change" to lower LDL; while 24 percent would have met the criteria for "drug consideration" for lowering LDL.
During more than 10 years of follow-up, 179 of the men in the study died from cardiovascular disease. Compared with men who met the acceptable LDL levels, men who required changes in diet and exercise were at twice the risk of cardiovascular death, while men who needed aggressive cholesterol-lowering drug therapy were at almost seven times the risk, the researchers report.
In addition, the researchers found that one-third of the men in the highest cholesterol group also had signs of metabolic syndrome. Metabolic syndrome means having three or more of the following cardiovascular risk factors: abdominal obesity, high levels of blood fats called triglycerides, low HDL cholesterol, high blood pressure or high blood glucose. Metabolic syndrome, even without high LDL cholesterol, doubles the risk of death from cardiovascular disease.
According to Katzmarzyk, 25 percent of Americans aged 20 to 79 need aggressive lipid-lowering therapy. "These new guidelines will definitely save lives if they are implemented," he said.
An exciting finding was that men who were physically active had a significantly reduced risk of dying from cardiovascular disease regardless of their cholesterol level. "Men who were physically active had a 50 percent reduction in risk," Katzmarzyk said.
The reason physical fitness reduces cardiovascular risk is that all of the risk factors that makeup metabolic syndrome are sensitive to exercise, said study co-author Dr. Timothy S. Church, medical director at The Cooper Institute, in Dallas.
"It shouldn't be called metabolic syndrome," Church said. "It should be called physical inactivity syndrome."
Church believes that exercise can dramatically reduce the growing epidemic of metabolic syndrome in the U.S. "If you want to prevent developing metabolic syndrome, lead a physically active life," he said. "Being physical active only takes 30 minutes a day, five days a week -- incorporate physical activity into your life."
One expert wasn't surprised by the findings.
"It's telling you that patients with risk factors are at higher risk," said Dr. Harlan M. Krumholz, a professor of cardiology at Yale University Medical School. "It kind of makes sense that if you have some of these risk factors, you are at high risk."
The American Heart Association can tell you more about physical activity and reducing heart disease.