Longitudinal increase in physical activity and adverse cardiovascular outcomes following the diagnosis of acute coronary syndrome

Objectives Physical activity (PA) provides protective effects against cardiovascular diseases, including ischaemic heart disease. However, recommending moderate to vigorous PA (MVPA) to patients with recent acute coronary syndrome (ACS) raises concerns owing to potential risk of recurrent ACS or fatal arrhythmias. This study investigated the association between longitudinal PA changes following an ACS diagnosis and subsequent cardiovascular outcomes, including non-fatal coronary events, non-fatal stroke and cardiovascular mortality. Methods This longitudinal cohort study used Korean National Health Insurance Service data from 2010 to 2017, comprising 30 840 patients diagnosed with ACS following invasive coronary angiography or bypass surgery. Leisure-time PA was self-reported, with the frequency and intensity measured weekly. The primary endpoint was a composite of nonfatal coronary events, non-fatal stroke and cardiovascular mortality. Multivariable Cox proportional hazards regression models assessed the association between PA changes and cardiovascular outcomes. Results Among patients with ACS (mean age: 60±11 years, men: 81.3%), mean PA levels increased from 544±556 metabolic equivalent task (MET)-min/week to 594±567 MET-min/week. Over 6.7 years of median follow-up, 5639 cardiovascular events occurred. Increased PA was associated with lower cardiovascular event risk (HR 0.95, 95% CI 0.92 to 0.98). Consistent MVPA pre-ACS and post-ACS reduced cardiovascular event risk (HR 0.87, 95% CI 0.79 to 0.96) and MVPA initiation showed a modest risk reduction (HR: 0.91, MET-min/95% CI 0.82 to 1.01). Conclusions Longitudinal increases in self-reported PA, maintenance of MVPA and possibly MVPA initiation after ACS reduced the risk of cardiovascular events. Initiating or maintaining MVPA could be an important strategy in improving cardiovascular outcomes following ACS.