The Effect of Exercise Training on Cardiovascular Mortality Risk

Abstract

Clinicians use risk calculators in primary prevention to estimate CVD mortality. A potential limitation of available risk calculators are they generally estimate risk based on traditional risk factors, which is problematic since cardiorespiratory fitness (CRF)/physical activity are independent predictors of CVD. To address the limitations, Wickeramasinghe et al. developed a calculator to assess 30-year CVD risk that includes CRF as a variable, along with traditional risk factors, but few studies have evaluated the impact of aerobic training on this risk score. The purpose of the present study was to evaluate the effect of aerobic exercise training on 30-year CVD risk. METHODS: The study included adults with elevated CRP levels who were randomized to an aerobic exercise group or a control group. Baseline and follow-up data (age, total cholesterol, systolic blood pressure, diabetes, body mass index, fitness level, and smoking status) were entered into the Wickeramasinghe et al. [1] calculator to calculate 30-year CVD mortality risk. The aerobic exercise intervention lasted 4 months and individuals expended approximately 16 kcal/kg per week (KKW). The control group was asked to maintain their sedentary status over the course of the intervention. RESULTS: A significant reduction in 30- year CVD risk mortality was observed between the exercise and the control group following the intervention (-0.5[CI: -1.3,0.4] versus -2.0[CI: -2.9, -1.1]. There was a significant increase in METs following the aerobic exercise intervention (p<.0001), but there was no significant changes in body mass index, total cholesterol, or systolic blood pressure. Also further, among those with high CVD risk a reduction in 30- year CVD mortality risk between the control group (-1.3[ CI: -2.8, 0.26] )and the exercise group (-3.5[CI:-5.5,-1.6]) following the exercise intervention approached significance. DISCUSSION: Results from the present study suggest that four months of aerobic exercise training resulted in a small reduction in estimated 30-year CVD mortality in a risk calculator that includes traditional risk factors and CRF. Future studies should investigate the relationship between CRF and estimated CVD mortality following a longer aerobic exercise intervention, in different study populations, and following different aerobic exercise programs.