Outcomes and Practice Patterns of Long-Acting Injectable Versus Oral Antipsychotics Among Patients With Bipolar I...

Objective: To compare rehospitalization outcomes and medication practice patterns between long-acting injectable antipsychotics (LAIs) and oral antipsychotics (OAs) in US patients with bipolar I disorder (BD-I).

Methods: This retrospective cohort study using the Premier Hospital database (October 2020-September 2023) grouped adults (aged ≥18 years) hospitalized with BD-I by discharge medication: OA, LAI, or second-generation LAI (SG LAI). LAI and SG LAI patients were propensity score matched (1:4) to OA patients. Rehospitalization rates and risk (BD-I-related and all-cause) within 30, 60, and 90 days were assessed. Medication continuation vs switching at rehospitalization was also analyzed.

Results: Among 98,088 eligible patients, 78.1% were in the OA and 2.4% in the LAI group. BD-I-related rehospitalization rates were lower for LAI users at 30 (3.9% vs 5.0%, P=.033) and 60 days (5.9% vs 7.2%, P=.030) vs OAs. SG LAI users showed reductions in rehospitalizations at 30 (3.6% vs 5.4%; P=.010), 60 (5.2% vs 7.5%; P=.008), and 90 (6.8% vs 9.1%; P=.015) days. Risk of first BD-I rehospitalization within 30-90 days was reduced for LAI (hazard ratio [HR]: 0.784-0.856) and SG LAI (HR: 0.653-0.742) groups vs OAs.

Conclusions: LAIs, especially SG formulations, are associated with reduced rehospitalization in BD-I compared to OAs, supporting their broader use to improve adherence and reduce readmissions.