Abstract 18133: Between- and Within-Person Changes in Weight and Cardiorespiratory Fitness and the Effect on Blood Pressure and Lipids in Men and Women From the Cooper Center Longitudinal Study

Abstract

Introduction: Cardiovascular disease (CVD) is the leading cause of death in the U.S. Controlling risk factors such as hypertension and dyslipidemia by maintaining a healthy weight and achieving an adequate level of cardiorespiratory fitness (CRF) could result in improvements in cardiovascular health. The Cooper Center Longitudinal Study is the most extensive resource available for evaluating the simultaneous effects of changes in weight and CRF on CVD risk factors. Objective: The purpose of this study was to evaluate the within-person relationships between body weight, CRF, and CVD risk factors, while controlling for the corresponding between-person relationships. We hypothesized that increases in weight and decreases in CRF over a ten-year time period would result in detrimental effects on blood pressure and lipids, and vice-versa. Methods: The study sample consisted of 4,439 men and 651 women who had at least 5 preventive medical examinations during any ten year period from 1977 to 2006. The examination included a maximal exercise test, anthropometric and clinical measures, and a medical history questionnaire. Linear mixed-effects regression was used to model the cardiovascular risk factors over time, providing estimates of between- and within-person effects. Results: Aging alone did not significantly predict changes in CVD risk factors in women or men after adjustment for covariates including CRF and weight, with the exception of total and LDL cholesterol in men. Increases in body weight were associated with increases in systolic and diastolic blood pressure, total cholesterol, LDL, and triglycerides and decreases in HDL in women and men. The largest effect of weight gain for women and men was seen in triglycerides, with a 2.29 mg/dL and 3.57 mg/dL increase per pound of weight gained per year, respectively ( P < 0.001). Increases in CRF were associated with improvements in diastolic blood pressure [-0.39 mmHg (women); -0.10 mmHg (men)] and HDL [0.35 mg/dL (women); 0.63 mg/dL (men)] over time and in triglycerides (-2.26 mg/dL) in men only ( P < 0.05 for all). Conclusion: Changes in body weight over a ten year period predicted changes in all CVD risk factors examined in women and men; whereas changes in CRF predicted changes in diastolic blood pressure and HDL.