Hospitalization Risk among Adults with Bipolar I Disorder Treated with Oral Atypical Antipsychotics: A Long-Term Retrospective Analysis of Medicaid Claims Data

Objective: To compare the risk of hospitalization for adults with bipolar I disorder (BPD-I) when treated with lurasidone vs. other atypical antipsychotics (AAPs) as monotherapy.

Methods: Using IBM MarketScan Multi-State Medicaid Claims database, a retrospective cohort study was conducted on 8262 adult BPD-I patients who initiated an AAP (index date) between January 1, 2014 and June 30, 2019 and were continuously enrolled during 12-months pre- and 24-months post-index date. AAP cohort was categorized into lurasidone (14%), aripiprazole (17%), olanzapine (8%), quetiapine (29%), risperidone (10%), no/minimal (1%) or other (21%) during each month of post-index period. Marginal structural models were performed to estimate risk of hospitalization (all-cause, BPD-I-related, and psychiatric-related) associated with each AAP while adjusting for covariates.

Results: The adjusted odds ratios (aORs) for all-cause hospitalization were significantly higher for olanzapine (aOR 1.60, 95% CI 1.09-2.10) and quetiapine (aOR 1.54, 95% CI 1.18-1.89), compared to lurasidone. The aORs for BPD-I-related hospitalization were significantly higher for quetiapine (aOR 1.57, 95% CI 1.10-2.04) and risperidone (aOR 1.80, 95% CI 1.04-2.56), compared to lurasidone. The average length of hospital stay was more than twice as high for quetiapine compared to lurasidone (aRR 2.12, 95% CI 1.32-2.92). Risk of psychiatric-related hospitalization was numerically lower for lurasidone compared to all other AAPs.

Conclusion: Over a 24-month follow-up period, lurasidone-treated adult BPD-1 patients had significantly lower risk of all-cause hospitalization than those treated with olanzapine and quetiapine, lower risk of BPD-I-related hospitalization than quetiapine and risperidone, and fewer hospital days than quetiapine in a Medicaid population.