Treatment Patterns, Healthcare Resource Utilization and Costs Among Schizophrenia Patients Treated with Long-Acting Injectable Versus Oral Antipsychotics

Introduction: Long-acting injectable (LAI) antipsychotic use may reduce healthcare resource utilization compared with oral antipsychotic use by improving adherence and reducing dosing frequency. Our goal was to examine treatment patterns, healthcare utilization, and costs among recently diagnosed schizophrenia patients receiving oral versus LAI antipsychotics.

Methods: The MarketScan Multi-state Medicaid database was used to identify schizophrenia patients aged ≥ 18 years who received an LAI or oral antipsychotic between January 1, 2011 and December 31, 2014. Primary outcomes included treatment patterns such as adherence (measured as proportion of days covered-PDC), persistence, discontinuation, switching, and healthcare resource utilization and costs. Propensity score matching (PSM) was used to control for differences in baseline characteristics between the cohorts. Outcomes were assessed over a 12-month post-index period and compared between treatment cohorts.

Results: After PSM, 2302 patients were included in each of the LAI and oral antipsychotics cohorts. There were no differences in PDC or therapy switching between the two cohorts. Compared with the oral cohort, patients receiving LAIs had lower discontinuation rates (46.1 vs. 61.6%, p < 0.001), fewer inpatient admissions (0.5 vs. 0.9, p < 0.001), hospital days (3.9 vs. 6.5, p < 0.001), and ER visits (2.4 vs. 2.9, p = 0.007), and a higher number of prescription fills (29.5 vs. 25.3, p < 0.001). Patients prescribed LAIs had lower monthly inpatient ($US4007 vs. 8769, p < 0.001) and ER visits costs ($682 vs. 891, p < 0.001) but higher monthly medication costs ($10,713 vs. $655, p < 0.001) compared with the oral cohort over the 12-month post-index period. Overall, both cohorts had similar total medical costs (LAI vs. oral: $24,988 vs. 23,887, p = 0.354) during the follow-up period.

Conclusion: Patients receiving LAIs were more likely to remain on medication compared with the oral group, which may account for reduced inpatient admissions. Hospitalization cost reductions offset the higher costs of LAI medications, resulting in no increase in total healthcare costs relative to oral antipsychotic use.

Funding: Alkermes Inc.