Association between physical activity and mortality among community-dwelling stroke survivors

Objective:  To determine the relationship between physical activity and mortality in community-dwelling stroke survivors.

Methods:  The Canadian Community Health Survey was used to obtain self-reported physical activity (PA) across four survey years and was linked to administrative databases to obtain prior diagnosis of stroke and subsequent all-cause mortality.  PA was measured as metabolic equivalents (METs) per week and meeting minimal PA guidelines was defined as 10 MET-hours/week.  Cox proportional hazard regression models and restricted cubic splines were used to determine the relationship between PA and all-cause mortality in respondents with prior stroke and controls, adjusting for sociodemographic factors, co-morbidities, and functional health status.

Results:  The cohort included 895 respondents with prior stroke and 97805 controls.  Adhering to PA guidelines was associated with lower hazard of death for those with prior stroke (adjusted hazard ratio [aHR] 0.46, 95% CI 0.29-0.73) and controls (aHR 0.69, 95% CI 0.62-0.76). There was a strong dose-response relationship in both groups, with a steep early slope and the vast majority of associated risk reduction occurring between 0 and 20 MET-hours/week.  In the group of stroke respondents, PA was associated with stronger associated risk reduction in those <75 years of age (aHR 0.21, 95% CI 0.10-0.43) compared to those >75 years of age (aHR 0.68, 95% CI 0.42-1.12). 

Conclusions:  PA was associated with lower all-cause mortality in a dose-dependent manner among those with prior stroke, particularly in younger stroke survivors.  Our findings support efforts towards the implementation of PA programs for stroke survivors in the community.