Background and Purpose
Sufficient physical activity (PA) is highly recommended for better prognosis after stroke. But there have been few studies on changes in physical activity level before and after stroke, and its association with post-stroke hard outcomes, especially stroke recurrence. The purpose of this study is to identify the changes in physical activity level before and after ischemic stroke, and to find out their associations with adverse outcomes including mortality, myocardial infarction (MI), and stroke recurrence.
Methods
This observational retrospective cohort study was performed on the basis of the Nationwide Health Insurance Service (NHIS) database in South Korea. A total number of 55,759 subjects between the ages of 20 to 80, who had an ischemic stroke from 2010 to 2013 were included. Ischemic stroke was confirmed by the ICD code I63 or I64 with hospitalization and claim for computed tomography (CT) or magnetic resonance imaging (MRI). Subjects who got disability grading from 1 to 3 (who could not walk) were excluded. Subjects were divided into subgroups according to PA level (sufficient vs. insufficient) before and after stroke using questionnaire responses during the health check-up. Hard outcomes including mortality, MI (ICD code I21) and stroke recurrence (re-admission for ICD code I63 or I64 and claim for CT or MRI) were collected after stroke. Multivariate Cox proportional regression analysis was performed to identify the benefit for sufficient PA to reduce the adverse outcomes after ischemic stroke, with adjusting for possible confounders.
Results
Of the 55,759 subjects with ischemic stroke, only 22,737 (40.8%) participated in sufficient PA after stroke. Among subjects who showed insufficient PA (n=32,591), only 10,159 (31.2%) changed their PA to sufficient level after stroke. Forty-five percent of subjects became inactive after stroke among subjects who showed sufficient PA level (n=23,168) before stroke. Subjects who changed their PA level from insufficient to sufficient level after stroke showed lower risk of adverse hard outcomes (mortality: HR=0.659 (95% CI: 0.597-0.727), MI: HR=0.897 (95% CI: 0.763-1.055), stroke recurrence: HR=0.820 (95% CI: 0.751-0.895)) than those who maintained insufficient PA level. Subjects who maintained sufficient PA level after stroke showed significantly lowest risk for all adverse hard outcomes (mortality: HR=0.571 (95% CI: 0.513-0.634), MI: HR=0.643 (95% CI: 0.537-0.711), stroke recurrence: HR=0.691 (95% CI: 0.631-0.757) than those who maintained insufficient PA level after stroke.
Conclusion
Achieving sufficient PA level after ischemic stroke reduces adverse major events including mortality, MI and stroke recurrence. However, even in patients with ischemic stroke who might walk, changing to or maintaining sufficient PA level are difficult. Systematic rehabilitation strategies to improve the PA level after mild to moderate ischemic stroke is urgently required. |
