Stroke care and case fatality in people with and without schizophrenia: a retrospective cohort study

BACKGROUND: Schizophrenia is associated with an increased risk of death following stroke; however, the magnitude and underlying reasons for this are not well understood. OBJECTIVE: To determine the association between schizophrenia and stroke case fatality, adjusting for baseline characteristics, stroke severity and processes of care. DESIGN: Retrospective cohort study used linked clinical and administrative databases. SETTING: All acute care institutions (N=152) in the province of Ontario, Canada. PARTICIPANTS: All patients (N=52 473) hospitalised with stroke between 1 April 2002 and 31 March 2013 and included in the Ontario Stroke Registry. Those with schizophrenia (n=612) were identified using validated algorithms. MAIN OUTCOMES AND MEASURES: We compared acute stroke care in those with and without schizophrenia and used Cox proportional hazards models to examine the association between schizophrenia and mortality, adjusting for demographics, comorbidity, stroke severity and processes of care. RESULTS: Compared with those without schizophrenia, people with schizophrenia were less likely to undergo thrombolysis (10.1% vs 13.4%), carotid imaging (66.3% vs 74.0%), rehabilitation (36.6% vs 46.6% among those with disability at discharge) or be treated with antihypertensive, lipid-lowering or anticoagulant therapies. After adjustment for age and other factors, schizophrenia was associated with death from any cause at 1 year (adjusted HR (aHR) 1.33, 95% CI 1.14 to 1.54). This was mainly attributable to early deaths from stroke (aHR 1.47, 95% CI 1.20 to 1.80, with survival curves separating in the first 30 days), and the survival disadvantage was particularly marked in those aged over 70 years (1-year mortality 46.9% vs 35.0%). CONCLUSIONS: Schizophrenia is associated with increased stroke case fatality, which is not fully explained by stroke severity, measurable comorbid conditions or processes of care. Future work should focus on understanding this mortality gap and on improving acute stroke and secondary preventive care in people with schizophrenia.