Healthcare resource usage of schizophrenia patients initiating long-acting injectable antipsychotics vs oral.

OBJECTIVE: To compare hospitalizations and incidence of relapses among patients with schizophrenia initiating long-acting injectable (LAI) antipsychotics vs oral antipsychotics.

METHODS: Patients with schizophrenia initiating LAI antipsychotics or oral antipsychotics (index events) were identified from large databases (MarketScan; Truven Health Analytics, CA), containing commercial and Medicare healthcare claims and their pre-index (12-month baseline period) and post-index (12-month follow-up period) hospitalizations and relapse rates were compared. Descriptive and bivariate statistics were utilized to compare demographics, clinical characteristics, and hospital resource usage among cohorts. Multivariate analysis was used to evaluate the impact of initiating LAI vs oral antipsychotics on differences in the number of hospitalizations and length of stay (LOS) between follow-up and baseline periods.

RESULTS: Commercially insured patients initiating LAI antipsychotics (n = 394) had significant reductions in inpatient healthcare usage after initiating antipsychotic therapy: mean number (±standard deviation) of all cause hospitalizations (1.60 ± 1.66 vs 0.70 ± 1.20, p < 0.001), LOS (16.9 ± 20.7 vs 6.6 ± 14.4 days, p < 0.001), schizophrenia-related hospitalizations (1.03 ± 1.26 vs 0.43 ± 0.86, p < 0.001), associated LOS (12.3 ± 17.7 vs 4.8 ± 12.8 days, p < 0.001). Patients initiating LAI vs oral antipsychotics (n = 2610) had significantly greater reductions during the follow-up period vs baseline period in the mean number of all cause hospitalizations (-0.90 ± 1.77 vs 0.02 ± 1.49, p < 0.001), LOS (-10.3 ± 23.2 vs 0.7 ± 16.7 days, p < 0.001), schizophrenia-related hospitalizations (-0.60 ± 1.37 vs 0.05 ± 0.99, p < 0.001) and associated LOS (-7.5 ± 20.7 vs 0.6 ± 12.5 days, p < 0.001). These results were further supported by multivariate analyses in which patient characteristics were taken into consideration.

LIMITATIONS: This study attempted to minimize the impact of differences in patient characteristics by having patients serve as their own controls in the before vs after comparison followed by multivariate regressions, however one still may not be able to account for all confounders in this non-randomized study population.

CONCLUSION: Patients with schizophrenia who initiated LAI vs oral antipsychotics experienced reductions in hospitalizations and schizophrenia relapses after drug initiation, which may be indicative of improved disease management.