Physical Activity, Subclinical Myocardial Injury, and Risk of Heart Failure Subtypes in Black Adults

Abstract Objectives This study sought to evaluate the independent associations and interactions between high-sensitivity cardiac troponin I (hs-cTnI) and physical activity (PA) with risk of heart failure (HF) subtypes, HF with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF). Background Black adults are at high risk for developing HF. Physical inactivity and subclinical myocardial injury, as assessed by hs-cTnI concentration, are independent risk factors for HF. Methods Black adults from the Jackson Heart Study without prevalent HF who had hs-cTnI concentration and self-reported PA assessed at baseline were included. Adjusted Cox models were used to evaluate the independent and joint associations and interaction between hs-cTnI concentrations and PA with risk of HFpEF and HFrEF. Results Among 3,959 participants, 25.1% had subclinical myocardial injury (hs-cTnI ≥4 and ≥6 ng/l in women and men, respectively), and 48.2% were inactive (moderate-to-vigorous PA = 0 min/week). Over 12.0 years of follow-up, 163 and 150 participants had an incident HFpEF and HFrEF event, respectively. In adjusted analysis, higher hs-cTnI concentration (per 1-U log increase) was associated with higher risk of HFpEF (hazard ratio [HR]: 1.47; 95% confidence interval [CI]: 1.25 to 1.72]) and HFrEF (HR: 1.57; 95% CI: 1.35 to 1.83]). In contrast, higher PA (per 1-U log increase) was associated with a lower risk of HFpEF (HR: 0.93; 95% CI: 0.88 to 0.99]) but not HFrEF. There was a significant interaction between hs-cTnI and PA for risk of HFpEF (p interaction = 0.04) such that inactive participants with subclinical myocardial injury were at higher risk of HFpEF but active participants were not. Conclusions Among Black adults with subclinical myocardial injury, higher levels of PA were associated with attenuated risk of HFpEF.