A retrospective, exploratory, secondary analysis of the association between antipsychotic use and mortality in elderly patients with delirium

Background: Delirium, an acute altered level of cognition, is a frequent complication of medical illness in the elderly. Antipsychotic medications (APs) are often used to treat agitation and psychosis in delirium. The goal of this study is to compare mortality in delirious elderly medical inpatients treated with APs with those who did not receive APs. Method: 326 elderly hospitalized patients were identified with delirium at an acute care community hospital. A nested case-control analysis was conducted on this cohort. Cases consisted of all patients who died in hospital within eight weeks of admission. Each case was matched for age and severity of illness to patients (controls) alive on the same day post-admission. Conditional logistic regression was used to assess the impact of exposure to AP on mortality. Covariates used for adjustment were the Charlson comorbidity score and the acute physiology score. Odds ratio (OR) and 95% confidence intervals were calculated from the regression coefficients. Results: 111 patients received an AP. A total of 62 patients died, 16 of whom were exposed to an AP. The OR of association between AP use and death was 1.53 (95% C.I, 0.83–2.80) in univariate and 1.61 (95% C.I, 0.88–2.96) in multivariate analysis. Conclusion: In elderly medical inpatients with delirium, administration of APs was not associated with a statistically significant increased risk of mortality. Larger studies are needed to clarify the safety of AP medication in elderly patients with delirium.