Treatment discontinuation and clinical outcomes in the 1-year naturalistic treatment of patients with schizophrenia at risk of treatment nonadherence

Katarina Kelin¹, Timothy JR Lambert², Alan JM Brnabic³, Richard Newton⁴, Wendy Ye³, Raúl I Escamilla⁵, Kuang-Peng Chen⁶, Liana Don⁷, William Montgomery¹, Jamie Karagianis⁸, Haya Ascher-Svanum^9
1Eli Lilly Australia Pty Ltd, West Ryde, NSW, Australia; ²Discipline of Psychiatry, Brain and Mind Research Institute, The University of Sydney, Camperdown, NSW, Australia; ³Intercontinental Information Sciences, Eli Lilly Australia Pty Ltd, Macquarie Park, NSW, Australia; ⁴Peninsula Health Psychiatric Services, Frankston Hospital, Frankston, VIC, Australia (current affiliation: Department of Psychiatry, Austin Hospital, Heidelberg, VIC, Australia); ⁵Schizophrenia Clinic, National Institute of Psychiatry, Mexico City, Mexico; ⁶Department of Psychiatry, National Taiwan University Hospital, Yun-Lin, Taiwan; ⁷Department of Psychiatry, University of Medicine Iuliu Hatieganu Cluj Napoca, Romania; ⁸Lilly USA, Eli Lilly and Company, Indianapolis, IN, USA; ⁹Global Health Outcomes, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USA

Background: This study aimed to improve physicians' understanding of the treatment circumstances and needs of outpatients with schizophrenia at risk of nonadherence, by naturalistically assessing antipsychotic treatment patterns, clinical outcomes, and health care service use in this little-studied patient population.
Methods: In this one-year, prospective, multicenter, noninterventional, observational study, patients considered at risk of nonadherence by their physicians were switched from their primary oral antipsychotic to another oral or a depot antipsychotic at study entry. All cause treatment discontinuation (antipsychotic switch, augmentation, or discontinuation) during the study was assessed using Kaplan–Meier survival analyses and descriptive statistics. Patients’ illness severity, quality of life, attitude towards medication, patient-reported adherence, and health care resource utilization were assessed during the study.
Results: Of the 406 enrolled patients, 43 (10.6%) were switched to depot and 363 (89.4%) were switched to oral antipsychotics at study entry. During the study, 99 (24.4%) patients switched, augmented, or discontinued their antipsychotic (all cause treatment discontinuation). Of the 99 patients who switched, augmented, or discontinued their antipsychotic, 8 (18.6%) were taking depot and 91 (25.0%) were taking oral antipsychotics. These patients were switched to either depot (n = 15) or oral (n = 78) antipsychotics, or discontinued their antipsychotic medication (n = 6). Inadequate response was the most frequently reported reason for medication discontinuation. During the study, patients’ clinical and functional status improved significantly and service use was low. Most patients considered themselves to be adherent at study entry, and this favorable self-perception increased during the study (from 68.5% to 88.1%).
Conclusion: Although identified as at risk of nonadherence, few patients in this naturalistic study discontinued their prescribed antipsychotic medication during the study. The discrepancy between the physicians’ perception of their patient’s medication adherence and the patients’ self-perceived adherence highlights the need to better understand the underlying reasons for this phenomenon.

Keywords: antipsychotic drugs, medication persistence, outpatients, schizophrenia, depot antipsychotic, nonadherence