Longitudinal associations between stroke and psychosis: a population-based study

BackgroundThe co-occurrence of stroke and psychosis is a serious neuropsychiatric condition but little is known about the course of this comorbidity. We aimed to estimate longitudinal associations between stroke and psychosis over 10 years. MethodsA 10-year population-based study using data from the English Longitudinal Study of Ageing. A structured health assessment recorded (i) first-occurrence stroke and (ii) psychosis, at each wave. Each were considered exposures and outcomes in separate analyses. Logistic and Cox proportional hazards regression and Kaplan-Meier methods were used. Models were adjusted for demographic and health behaviour covariates, with missing covariates imputed using random forest multiple imputation. ResultsOf 19 808 participants, 24 reported both stroke and psychosis (median Wave 1 age 63, 71% female, 50% lowest quintile of net financial wealth) at any point during follow-up. By 10 years, the probability of an incident first stroke in participants with psychosis was 21.4% [95% confidence interval (CI) 12.1-29.6] compared to 8.3% (95% CI 7.8-8.8) in those without psychosis (absolute difference: 13.1%; 95% CI 20.8-4.3, log rank p < 0.001; fully-adjusted hazard ratio (HR): 3.57; 95% CI 2.18-5.84). The probability of reporting incident psychosis in participants with stroke was 2.3% (95% CI 1.4-3.2) compared to 0.9% (95% CI 0.7-1.1) in those without (absolute difference: 1.4%; 95% CI 0.7-2.1, log rank p < 0.001; fully-adjusted HR: 4.98; 95% CI 2.55-9.72). ConclusionsStroke is an independent predictor of psychosis (and vice versa), after adjustment for potential confounders.