Stroke rehabilitation is associated with a reduction in dementia risk: a population-based retrospective cohort study.

OBJECTIVE Focusing on the relationship between physical activity and incident cognitive impairment, the aim of this study was to investigate whether stroke rehabilitation reduces the risk of dementia. METHODS Claims data of 1,000,000 insured subjects randomly selected from the National Health Insurance programme of Taiwan were used to identify adults with a newly diagnosed ischaemic stroke in 1997-2002. Among them, 1,375 received rehabilitation and 3,722 did not. Both groups were followed up until the end of 2007 to measure the incidence of development of dementia. RESULTS The incidence of development of dementia was lower in the rehabilitation cohort than in the non-rehabilitation cohort (1.22 vs 1.70 per 100 person-years), with an adjusted hazard ratio (HR) of 0.73 (95% confidence interval (CI) = 0.60-0.89) in the multivariate Cox proportional hazard regression analysis. Female gender (HR = 1.26, 95% CI = 1.07-1.50), older age (HR = 7.71, 95% CI = 3.36-17.7), low income (HR = 1.82, 95% CI = 1.42-2.33), and Parkinson's disease (HR = 1.64, 95% CI = 1.33-2.03) were risk factors associated with the development of dementia. CONCLUSION Post-stroke rehabilitation is associated with a reduction in dementia risk among ischaemic stroke patients.