Post-stroke dementia is associated with increased subsequent all-cause mortality: A population-based cohort study

Abstract

Background and aimsWe aimed to determine whether patients with post-stroke dementia (PSD) have increased mortality risk in Taiwan. MethodsWe included ≥40-year-old patients who received a stroke diagnosis between 2000 and 2012 from a subset of the National Health Insurance Research Database of Taiwan. These patients were divided into PSD (International Classification of Diseases, Ninth Revision, Clinical Modification codes 290, 294.1, and 331.0) and post-stroke non-dementia (PSN) cohorts. Furthermore, we propensity score (PS) matched the PSD and PSN groups. PS was calculated through logistic regression to estimate the probability of stroke status assignment given the baseline variables, namely age, sex, and comorbidity. We calculated the adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for death in the PSD and PSN cohorts after adjustments for age, sex, and comorbidities. ResultsOverall incidence density rates of death were 148.7 and 106.7 per 1,000 person-years in the PSD and PSN PS-matched cohorts, with the aHR of 1.42 (95% CI = 1.34–1.50). Average hospital days increased by 9.03 days and frequency of medical visits increased by 15.8 times per year in the PSD cohort compared with the PSN cohort. ConclusionsThe subsequent mortality rate in patients with PSD is increased compared with those without PSD. Moreover, the average hospital days and frequency of medical visit are increased in patients with PSD. Our findings provide crucial information for clinicians and the government to improve survival of patients after stroke.