Exercise might help compensate for a high genetic risk of cardiovascular disease, according to the findings of a large prospective observational cohort study.
High-risk individuals in the top cardiorespiratory fitness tertile had a 49% lower risk of coronary heart disease (hazard ratio, 0.51; 95% confidence interval, 0.38-0.69) and a 60% lower risk of atrial fibrillation (HR, 0.40; 95% CI, 0.30-0.55) compared with those in the bottom fitness tertile, reported Emmi Tikkanen, PhD, of Stanford (Calif.) University, and her associates. The study was published in Circulation.
Little is known about whether exercise offsets genetic risk for cardiovascular disease. For the study, the researchers measured grip strength, cardiorespiratory fitness (based on net oxygen consumption while riding a stationary bicycle), cardiovascular events, and mortality among 482,702 participants in the UK Biobank longitudinal cohort study. More than half of individuals were women and none had baseline evidence of heart disease. The researchers stratified cases of coronary artery disease (CHD) and atrial fibrillation (AF) by whether individuals were at high, intermediate, or low genetic risk based on genome-wide association data.
Over a median follow-up period of 6.1 years (interquartile range, 5.4 to 6.8 years), there were nearly 21,000 cardiovascular events, including more than 8,000 cases of CHD and nearly 10,000 cases of AF. For all risk groups, increased grip strength and cardiorespiratory fitness were associated with a significantly lower risk of CHD and AF (P less than .001), even after adjustment for demographic factors, diabetes, smoking, systolic blood pressure, body mass index, and use of lipid-lowering medications.
The researchers did not look closely at types or durations of exercise. “Future studies evaluating the effects of strength versus aerobic training on subclinical or clinical cardiovascular outcomes could help to tailor exercise programs for individuals with elevated genetic risk for these diseases,” they wrote.
Funders included the National Institutes of Health, Knut and Alice Wallenberg Foundation, Finnish Cultural Foundation, Finnish Foundation for Cardiovascular Research, and Emil Aaltonen Foundation. Coauthor Erik Ingelsson, MD, disclosed advisory relationships with Precision Wellness and Olink Proteomics. The other authors reported having no conflicts of interest.
SOURCE: Tikkanen E et al. Circulation. 2018 Apr 9. doi: 10.1161/CIRCULATIONAHA.117.032432.