The Impact of Antipsychotic Dose Reduction on Clinical Outcomes and Health Care Resource Use Among Medicare Patients with Schizophrenia.

Background: Antipsychotic medications are used to treat schizophrenia and may be associated with adverse effects, including tardive dyskinesia (TD), following prolonged use or upon changes in dosing regimen.

Objective: This retrospective analysis evaluated the burden of antipsychotic dose reduction in Medicare patients with schizophrenia.

Methods: This matched cohort study used Medicare claims data (2006-2017) analyzed for patients with schizophrenia and two or more claims for antipsychotics, with one or more antipsychotic monotherapy period ≥ 90 days. Cohorts were defined for patients with antipsychotic dose reductions ≥ 10% and stable doses. A separate analysis was conducted using patients with dose reductions ≥ 30%. Outcomes included all-cause emergency room (ER) visits, all-cause inpatient visits, schizophrenia relapse, other psychiatric relapse, and TD diagnosis. Covariates included age, disease duration, comorbidities, and medication use.

Results: The analysis included 276,030 patients with ≥ 10% dose reductions and 211,575 patients with ≥ 30% dose reductions. Patient characteristics were balanced between cohorts. Patients with ≥ 10% or ≥ 30% dose reductions had a shorter time to ER visit, inpatient visit, schizophrenia relapse, other psychiatric relapse, and TD diagnosis versus those receiving stable doses (all p < 0.001). Significance was maintained when unmatched baseline characteristics were adjusted.

Conclusions: Patients with antipsychotic dose reductions may be at risk for increased ER visits, increased hospitalizations, and significant unfavorable mental health-related clinical outcomes, suggesting that dose reduction may increase overall health care burden in some patients with schizophrenia. This work highlights the need for alternative strategies in the management of patients with TD.