Physical activity lowers all-cause mortality after stroke, especially in younger patients

Physical activity correlated with decreased all-cause mortality in a dose-dependent matter among individuals with a history of stroke, especially younger individuals, according to findings published in Neurology.

“A better understanding of the role of physical activity in the health of people who survive stroke is needed to design better exercise therapies and public health campaigns so we can help these individuals live longer,” Raed A. Joundi, MD, DPhil, FRCPC, of the University of Calgary in Canada and a member of the American Academy of Neurology, said in a press release. “Our results are exciting, because just 3 to 4 hours a week of walking was associated with big reductions in mortality, and that may be attainable for many community members with prior stroke. In addition, we found people achieved even greater benefit with walking 6 to 7 hours per week. These results might have implications for guidelines for stroke survivors in the future.”

Joundi and colleagues aimed to determine the link between physical activity and mortality among community-dwelling individuals after a stroke. They used the Canadian Community Health Survey to collect self-reported data on physical activity in four survey cycles. The Canadian Community Health Survey was also linked to administrative databases, which the researchers used to gather data on prior stroke diagnoses and subsequent all-cause mortality.

The study protocol measured physical activity in metabolic equivalents (METs) per week, with 10 MET-hours per week as the threshold for meeting minimal physical activity guidelines. The researchers used Cox proportional hazard regression models and restricted cubic splines to assess the link between physical activity and all-cause mortality among those with a history of stroke as well as controls. They adjusted models for sociodemographic factors, comorbidities and functional health limitations, according to the study results.

The patient population included 895 individuals with a history of stroke and 97,805 control participants. Individuals with a prior stroke were older than control participants (mean age, 71.7 years vs. 63 years) and less likely to be women (42% vs. 51.5% of total population). Most participants with a history of stroke experienced an ischemic stroke (92%), according to the study results.

Median follow-up time from survey response to death or censoring was 4.8 years among control participants and 4.2 years among those with a history of stroke. The researchers reported a greater rate of deaths during the study period among those with a history of stroke (24.6%) compared with control participants (5.7%).

Joundi and colleagues found that adherence to physical activity guidelines correlated with a decreased hazard of death among those with a history of stroke (adjusted HR = 0.46; 95% CI, 0.29-0.73) as well as control participants (aHR = 0.69; 95% CI, 0.62-0.76). The researchers observed a robust dose-response connection in both groups, “with a steep early slope and the vast majority of associated risk reduction occurring between 0 and 20 MET-hours/week,” according to the study results. Among individuals with a history of stroke, physical activity was tied to a larger decrease in risk among those aged less than 75 years (aHR = 0.21; 95% CI, 0.1-0.43) compared with those aged 75 years and older (aHR = 0.68; 95% CI, 0.42-1.12).

“Achieving a weekly energy expenditure of at least 10 MET-hours/week (equivalent to 3-4 hours of walking) was associated with substantial mortality reductions for both stroke and control groups. Alternatively, similar associated reductions were seen with 5 or more episodes of leisure activity per week lasting >15 minutes,” the researchers wrote. “However, we found the relationship was modified by age, such that the greatest associated reductions in long-term mortality with physical activity occurred in stroke respondents <75 years of age.”

The findings indicated that enhancing physical activity may decrease long-term mortality among stroke survivors, especially among younger individuals, according to Joundi and colleagues.

“Existing guidelines for the general population can be reasonably applied to those with a history of stroke, with a minimal threshold of 10 MET hours/week. Specifically, greater emphasis should be placed on regular exercise for younger stroke survivors, as even small weekly amounts of exercise, in either total amount or frequency, were associated with large mortality reductions,” the researchers wrote. “Our findings, together with previous data indicating that encouragement alone is not enough, support efforts towards understanding and reducing barriers to physical activity and implementation of structured programs for physical activity among community-dwelling stroke survivors.”

Reference:

People with stroke who walk 30 minutes per day may have 54% lower risk of death. Available at: https://www.aan.com/PressRoom/Home/PressRelease/4916. Accessed Aug. 11, 2021.