All-cause hospitalization and associated costs in patients with schizophrenia or bipolar disorder initiating long-acting injectable antipsychotics.

OBJECTIVE: To compare all-cause hospitalization and associated costs among patients with schizophrenia or bipolar disorder (BD) treated with long-acting injectable antipsychotics (LAIs).

METHODS: The Truven MarketScan Medicaid claims database was used to identify patients with schizophrenia; MarketScan Medicaid and commercial claims databases were used to identify BD. Adult patients with ≥1 LAI claim from January 1, 2013-June 30, 2014 (ID period) were identified. The first day of LAI initiation was the index date; patients were followed for ≥1 year. Logistic and general linear regression models were used to estimate the risk of hospitalization and associated costs.

RESULTS: Adjusted analyses showed that, in the schizophrenia cohort, risks of hospitalization were statistically significantly higher in the haloperidol [OR (95% CI) = 1.51 (1.05-2.16); HR (95% CI) = 1.35 (1.05-1.73)] and risperidone [OR (95% CI) = 1.58 (1.07-2.33); HR (95% CI) = 1.33 (1.01-1.74)] cohorts than in the aripiprazole once monthly extended release (AOM 400) cohort. Similarly, in patients with BD, risks of hospitalization were significantly higher in haloperidol [OR (95% CI) = 1.49 (1.01-2.19); HR (95% CI) = 1.33 (1.03-1.73)] and risperidone [OR (95% CI) = 1.78 (1.19-2.66); HR (95% CI) = 1.33 (1.01-1.75)] than in AOM400. No statistically significant differences in hospitalization costs were observed in either disease group.

CONCLUSIONS: Although the study results may be subject to confounding variables that are not contained in claims databases, such as disease severity, it appears that AOM400 may be more effective than haloperidol and risperidone LAIs among patients with schizophrenia or BD.