Physical Activity and Functional Capacity Measurement in Women: A Report from the NHLBI-Sponsored WISE Study

Abstract

Physical activity and functional capacity have not been assessed by questionnaire for criterion validity in women. We wished to evaluate the ability of a physical activity and a functional capacity assessment questionnaire to predict functional capacity measured by treadmill exercise stress testing, as well as correlate with cardiac risk factors and angiographic coronary artery disease (CAD) in women. In a National Heart, Lung and Blood Institute (NHLBI)-sponsored cross-sectional population study involving four academic medical centers, 476 women with cardiac risk factors undergoing coronary angiography for evaluation for suspected myocardial ischemia were enrolled in the Women's Ischemia Syndrome Evaluation (WISE). The main outcome measures were functional capacity measured during symptom-limited exercise treadmill testing, cardiac risk factors, and CAD, using core laboratory-determined measures. Physical activity measured by the Postmenopausal Estrogen and Progesterone Intervention physical activity questionnaire(PEPI-Q) and functional capacity measured by the Duke Activity Status Index (DASI) questionnaire, correlated with functional capacity measured in metabolic equivalents (METS), as estimated during symptom-limited exercise treadmill testing (r = 0.27, p = 0.001 and r = 0.31, p = 0.0002, respectively). The DASI was a significant independent predictor of functional capacity even after adjustment for cardiac risk factors, and the PEPI-Q was not. The DASI and PEPI-Q scores were inversely associated with higher numbers and levels of cardiac risk factors, as well as angiographic CAD. The DASI questionnaire is a reasonable correlate of functional capacity achieved during symptom-limited treadmill exercise testing in women with suspected myocardial ischemia. Lower functional capacity or physical activity measured by the DASI and PEPI-Q, respectively, is associated with more prevalent cardiac risk factors and angiographic CAD. These findings suggest that the DASI and, to a lesser extent, the PEPI-Q have criterion validity for use in health-related research in women.