Measuring a womans fitness gives a clearer indication of coronary artery disease than measuring obesity

Sep 8 2004

Women reporting higher levels of physical fitness have fewer coronary artery disease risk factors, less coronary artery disease, and a lower risk for cardiovascular events, whereas measures of obesity are not as strongly associated with these outcomes, according to a study in the September 8 issue of JAMA.

Individual contributions of obesity and physical fitness (physical activity and functional capacity) to risk of coronary heart disease (CHD) in women remain unclear, according to background information in the article. Most obesity studies have not adequately measured physical activity and many studies of physical fitness have excluded women with known or suspected coronary heart disease.

Timothy R. Wessel, M.D., of the University of Florida College of Medicine, Gainesville, and colleagues investigated the relationships of physical fitness and obesity measures with CHD risk factors, coronary angiographic findings, and adverse cardiovascular events among a group of women undergoing coronary angiography to evaluate suspected ischemia.

The study (Women’s Ischemia Syndrome Evaluation [WISE]) included measures of obesity (body mass index [BMI] waist circumference, waist-hip ration, and waist-height ratio) and physical fitness (self-reported Duke Activity Status Index [DASI] and Postmenopausal Estrogen-Progestin Intervention questionnaire [PEPI-Q] scores). Participants included 936 women enrolled at four U.S. academic medical centers, 1996-2000, at the time of coronary angiography, and then assessed for adverse outcomes (average follow-up time, 3.9 years).

The researchers found that of 906 women with complete data, 76 percent were overweight, 70 percent had low functional exercise capacity, and 39 percent had obstructive coronary artery disease (CAD). “During follow-up, 337 (38 percent) women had a first adverse event, 118 (13 percent) had a major adverse event, and 68 (8 percent) died. Overweight women were more likely than normal weight women to have CAD risk factors, but neither BMI nor abdominal obesity measures were significantly associated with obstructive CAD or adverse cardiovascular (CV) events after adjusting for other risk factors,” the authors write. “Conversely, women with lower DASI scores [lower levels of physical fitness] were significantly more likely to have CAD risk factors and obstructive CAD (44 percent vs. 26 percent) at baseline, and each 1-MET [measure of energy expenditure] increase in DASI score was independently associated with an 8 percent decrease in risk of major adverse CV events during follow-up.”

“These results suggest that fitness may be more important than overweight or obesity for CV risk in women. Evaluation of physical activity and functional capacity using simple questionnaires should be an integral part of CV risk stratification, and interventions aimed at increasing physical fitness levels should be included in the management of all women at risk for CHD,” the authors conclude.

http://www.jama.com