| Abstract: | Objective: Assess the association of schizophrenia patients' perceived copayment burden with medication adherence and outcomes.Methods: Patients with schizophrenia (aged 18+) completed self-reported questionnaires. Analyses included those currently using a second-generation antipsychotic (SGA) with no exposure to clozapine or depot formulation antipsychotics. Adherence was assessed using the Morisky Medication Adherence Scale (MMAS). Outcomes included emergency room (ER) use, hospitalization, attempted suicide, missed work due to health, and experiencing severe psychological distress. Logistic regression was used to adjust for demographics, health characteristics, psychotropic medication use, and insurance status.Results: Of 351 schizophrenia patients, 39% perceived copayment burden. These patients were less than half as likely to have complete adherence OR = 0.427; 95% CI:0.257, 0.711; p = 0.001] Copayment burden was associated with greater likelihood of ER use, OR = 2.157; 95% CI:(1.322, 3.520); p = 0.002], hospitalization OR = 2.512; 95% CI: (1.475, 4.277); p < 0.001], attempted suicideOR = 2.385; 95% CI: (1.156, 4.920); p = 0.019], severe psychological distress OR = 1.833; 95% CI:1.092, 3.075; p = 0.022] and greater likelihood of missing work OR = 7.193; 95% CI: 2.554, 20.256; p < 0.001].Conclusions: Copayment burden is associated with poorer medication adherence and outcomes. Formularies that reduce copayment burden for SGAs may positively affect medication adherence and outcomes among schizophrenia patients.Limitations: Patient data were self-reported, which may have introduced additional bias in the study measures. Also, the use of a cross-sectional design precludes causal inference and the use of the current sampling methodology (both interview and Internet panel) might impact the ability to generalize the results to the broader population. |
