Abstract
BACKGROUND: Social isolation and loneliness, the rising social determinant of health, are prevalent in stroke survivors. We aimed to investigate whether social isolation and loneliness are associated with poor outcomes after stroke.
METHODS: A total of 394,308 individuals (mean ± SD age, 55.9 ± 8.1 years, 55.7% female, 95.4% White) from the UK Biobank were included in this study. 7267 (1.8%) had a prevalent stroke at baseline, while the remaining 387,041 (98.2%) had no history of stroke. Stroke history was ascertained at baseline using both self-reported data and electronic health records. Social isolation and loneliness were assessed using self-reported questionnaires. Stroke history was defined by self-report and electronic health records. Post-stroke outcomes, including all-cause mortality, CVD mortality, all-cause dementia, CVD and depression, were identified by linking hospital records and death registries.
RESULTS: During a median follow-up of 10.2 years, 2906 of the 7267 baseline stroke survivors experienced post-stroke outcomes. In fully adjusted models, social isolation was independently associated with higher risks of all-cause mortality (HR: 1.41, 95% CI: 1.20-1.64), CVD mortality (HR: 1.57, 1.26-1.96), and depression (HR: 1.35, 1.07-1.69). Loneliness was linked to increased risks of all-cause mortality (HR: 1.23, 1.01-1.50), CVD mortality (HR: 1.45, 1.11-1.87), all-cause dementia (HR: 1.67, 1.12-2.49), and depression (HR: 1.43, 1.09-1.88). These associations-particularly for all-cause mortality (Pinteraction = 0.006) and CVD mortality (Pinteraction = 0.042)-were more pronounced in stroke survivors than in those without stroke. Health behaviours mediated a substantial proportion of the associations for social isolation (32-55%) and loneliness (12-50%) with most outcomes.
CONCLUSIONS: Social isolation and loneliness were associated with greater risks for developing premature death, CVD, dementia, and depression after stroke. The findings highlighted strengthening social connections to improve stroke prognosis.