Post-stroke delirium in relation to dementia and long-term mortality

Background Delirium is a frequent post-stroke complication that compromises effective rehabilitation and has been associated with poor outcome. We aimed to investigate whether delirium is associated with increased risk of post-stroke dementia and long-term mortality once confounding is taken into account. Methods The study comprised 263 consecutive acute ischemic stroke patients aged 55-85years admitted to the emergency department of a university hospital. The cohort included three-month survivors followed up for 10years. The diagnosis of post-stroke delirium during the first 7days after stroke was based on the DSM-IV criteria. Findings Of all the patients, 50 (19.0%) were diagnosed with delirium. Low education, pre-stroke cognitive decline, and severe stroke indicated by a Modified Rankin score between 3 and 5 were risk factors for post-stroke delirium, which was also associated with diagnosis of dementia at 3months post-stroke. In the Kaplan-Meier analysis, delirium was associated with poor long-term survival (6.1 versus 9.1years). In the stepwise Cox regression proportional hazards analysis adjusted for demographic factors and risk factors, advanced age (hazard ratio [HR] 1.08) and stroke severity (HR 1.83), but not post-stroke delirium, were associated with poor survival. Interpretation In our well-defined cohort of post-stroke patients, acute stage delirium was diagnosed in one in five patients and associated with dementia at 3months. Advanced age and stroke severity were related to the higher long-term mortality among patients with post-stroke delirium.