Relapse and therapeutic interventions in a 1-year observational cohort study of nonadherent outpatients with schizophrenia

Abstract

To evaluate the incidence rate of relapse, the clinical profiles, and the therapeutic interventions employed for patients with schizophrenia deemed as likely nonadherers to oral antipsychotic drugs. A cohort of 597 outpatients whose therapy was modified because of a psychiatrist-perceived risk of nonadherence was followed for 12 months in an observational study. Baseline correlates of subsequent relapse were analyzed with Cox regression. At baseline, patients' mean (SD) age and time since diagnosis were 40.1 (11.1) and 15.2 (10.0) years, respectively; 63.7% were males. The Clinical Global Impression scale-Severity (CGI-S) score was ≥ 4 in 87.3% of the patients. Antipsychotic drugs were modified in 506 patients (84.8%); nonpharmacologic therapies were modified in 190 patients (31.8%). In both cases, the primary reason for the modifications was insufficient efficacy of current therapeutic regimen. The proportion of patients in oral antipsychotic monopharmacy decreased from 83.8% to 57.6%; 15.4% started long-acting (depot) formulations. Over the 12-month observation period, 90 patients (15.1%) relapsed. The hazard rate of relapse was higher in patients with substance use disorder or familial psychiatric antecedents and lower in patients who underwent modifications of nonpharmacological therapies or with negative attitude toward antipsychotic medication at baseline. Effective interventions to prevent relapse in patients with long-standing schizophrenia involving therapeutic challenges related to nonadherence are feasible. Rationale for the baseline correlates, and cues for clinical prevention of relapse in these patients are provided.