Association of physical activity with risk of major adverse cardiovascular events and mortality in Korean adults with hypertension

Background Whether higher volumes of physical activity (PA) and a greater proportion of vigorous-intensity physical activity (VPA) within total PA volume are associated with lower risks of major adverse cardiovascular events (MACE) and mortality remains unclear. This study aimed to examine the associations of total PA volume and the proportion of VPA within total PA volume with all-cause mortality and MACE among adults with hypertension. Methods This nationwide cohort study included 124,370 adults with hypertension from the Korean National Health Insurance Service database (2009–2012), with follow-up through 2019. MACE was defined as a composite of cardiovascular disease (CVD) mortality, myocardial infarction (MI), and ischemic stroke. Multivariate Cox proportional hazards models were used to estimate hazard ratios (HRs) for all-cause mortality and MACE. Results During a median follow-up of 9.1 years, 11,063 deaths occurred. Higher PA volumes were associated with stepwise reductions in all-cause and CVD mortality. In contrast, risk reductions for ischemic stroke plateaued at higher volumes, whereas reductions in MI risk were evident primarily at the highest volumes. Among 91,113 participants who engaged in any PA, a higher proportion of VPA was associated with lower risks of all-cause mortality (HR, 0.92; 95% confidence interval [CI], 0.87–0.98 for < 50% VPA and HR, 0.85; 95% CI, 0.78–0.93 for ≥ 50% VPA), MI (HR, 0.77; 95% CI, 0.67–0.89 and HR, 0.71; 95% CI, 0.58–0.86, respectively), and ischemic stroke (HR, 0.84; 95% CI, 0.76–0.92 for ≥ 50% VPA) after adjusting for total PA volume. No significant associations were observed between the proportion of VPA and CVD mortality. Conclusions Among adults with hypertension, a higher PA volume was associated with lower risks of all-cause and CVD mortality. Additionally, a greater proportion of VPA, after accounting for total PA volume, was associated with lower risks of MI and ischemic stroke. These findings suggest that both PA volume and intensity composition may be relevant for cardiovascular risk reduction in individuals with hypertension.