OBJECTIVES: Evaluate adherence to treatment and real-world outcomes in two cohorts of patients with serious mental illness (SMI).

METHODS: A retrospective cross-sectional analysis was used to compare patient characteristics and outcomes using a large sample of commercial, Medicare Advantage, and managed Medicaid claims data. Patients were included if they: 1) were enrolled with medical and pharmacy benefits for at least 180 days before and 360 days after the index event; 2) had at least one inpatient or two outpatient claims with a diagnosis for SMI and at least one prescription claim for an antipsychotic anytime between January 1, 2011 and June 30, 2016; and 3) were ≥ 18 and <65 years old at index date. The recently discharged (RD) cohort included patients with ≥1 SMI related hospitalization (first used as index event). The early episode (EE) cohort included patients with ≥ six-months of pre-index enrollment with no evidence of an antipsychotic or SMI diagnosis (first claim with either used as index event). The RD cohort included 11,050 patients:62% female; Age:9% 18-25, 35% 26-45, 56% 46-65. The EE cohort included 40,655 patients:63% female; Age:12% 18-25, 39% 26-45, 49% 46-65.

RESULTS: Adherence to oral antipsychotic medications (defined as PDC ≥.80) was 52.5% on average in the RD cohort, but only 16.1% on average in the EE cohort. Utilization rates per 1,000 patients were significantly higher in the RD cohort: PCP visits (6,170 vs 5,770); observation stays (400 vs. 160); emergency department visits (2,050 vs 1,170). Inpatient readmission rates were 220/1,000 in the EE cohort compared to 600/1,000 in the RD group.

CONCLUSIONS: Adherence to treatment is low and variable among SMI patients, resulting in high rates of healthcare utilization. These stratified outcomes can be used by providers to target specific SMI patients to reduce utilization and costs of care.