(379) Antipsychotic medication utilization and treatment patterns among patients with schizophrenia: A real-world evidence study

Background: : The primary treatment option for schizophrenia are antipsychotics, however these are associated with a variety of tolerability issues which impact adherence.

Objective: : To assess treatment patterns among patients with a diagnosis of schizophrenia receiving antipsychotic medications. Subgroup analyses were conducted among patients with comorbid hypertension to assess any differences in adherence to antipsychotics and antihypertensive medications.

Methods: : This was a retrospective analysis of the MORE2 Registry® and 100% Medicare Fee-for-Service (MFFS) claims databases spanning 1/1/2016 to 9/30/2023. Inclusion criteria: 1) ≥1 inpatient or ≥2 outpatient claims with a schizophrenia diagnosis, 2) ≥2 claims for an antipsychotic (earliest claim=index date), 3) ≥18 years on index, 4) ≥6 months of continuous enrollment prior to and ≥12 month following index, and 5) absence of claims for antipsychotics during the 6 month pre-index period. Subgroups were created based on route of administration (oral [OAP] vs. long-acting injectable [LAI]-containing), and evidence of comorbid hypertension. Medication adherence at the class level was assessed and defined as a proportion of days covered (PDC) ≥0.80 during follow-up. Antipsychotic treatment augmentation, treatment switching, and antihypertensive treatment adherence among the subgroup with hypertension were also assessed.

Results: : Overall, 212,770 patients with schizophrenia were included. Mean (SD) age was 46.3 (16.3) and the majority were male (54.9%). Most patients received OAPs only (82.3%); 15.9% received an LAI-containing regimen. Most common index antipsychotics were risperidone (21.1%), quetiapine (19.8%), and olanzapine (19.2%). Adherence was low for both OAPs (39.6%) and LAI-containing regimens (50.2%). Treatment switching was observed among 9.3% of the sample, while augmentation was observed among 4.8%. Augmentation and switching were two-fold more frequent among patients receiving LAI-containing regimens compared to OAPs. Among patients with comorbid hypertension (23.1%) only 47.4% were adherent to antipsychotics, while 66.1% were adherent to antihypertensives.

Conclusions: : Adherence to antipsychotic medication remains suboptimal among patients with schizophrenia living in the U.S. Among patients adherent to oral antihypertensives medications, adherence to antipsychotics remained low, suggesting selective nonadherence due to potential barriers specific to antipsychotics. Development of newer antipsychotics with improved tolerability may lead to increased adherence and improved clinical outcomes.

Sponsorship:: Bristol Myers Squibb