Abstract MP02: Dose Response Relationship Between Physical Activity and Risk of Heart Failure: A Meta-Analysis

Abstract

Background: Prior studies have shown qualitative inverse associations between physical activity (PA)/fitness and risk for heart failure (HF). However, a comprehensive assessment of the quantitative dose response association between PA and HF risk has not been reported.

Methods: Epidemiological studies that evaluated associations between PA/fitness and HF incidence were included. The categorical dose response association was evaluated by comparing the pooled HR for HF associated with different levels of PA (vs. lowest PA level) across studies. The continuous dose response was assessed among studies that allowed quantitative estimation of PA levels using generalized least square regression models.

Results: After reviewing 2,314 abstracts, 14 prospective cohort studies were included (PA = 12; Fitness = 2); eight allowed quantitative estimation of PA levels. On pooled analysis, we observed 21,114 HF events among 393,486 participants (52% women) during a median follow up period of 15.5 years. The highest levels of PA were associated with significantly reduced risk of HF [Pooled HR _{vs. lowest PA:} 0.68 (0.62-0.73)]. Furthermore, higher levels of PA were associated with lower risk of HF in categorical as well as continuous dose response analyses (Figure). Compared to participants reporting no leisure time PA, those who engaged in guideline recommended minimum levels of PA (500 MET*min/week, 2008 US Federal Guidelines) had only modest reductions in HF risk [HR: 0.90(0.87 - 0.92)]. In contrast, a substantial risk reduction was observed among individuals engaging in advanced guidelines recommended PA levels [1000 MET-min/week, HR: 0.81(0.76 - 0.85)]. The magnitude of HF risk reduction associated with highest levels of PA was similar in men and women with no significant interaction by sex. [P_interaction: 0.64].

Conclusion: There is an inverse dose response relationship between PA and HF risk. Higher doses of PA in excess of the current guideline recommended minimum PA levels might be required to significantly reduce the risk of HF.