Back to Journals » Patient Preference and Adherence » Volume 2

Adherence and persistence to typical and atypical antipsychotics in the naturalistic treatment of patients with schizophrenia

Authors Ascher-Svanum H, Zhu B, Faries D, Lacro J, Dolder C, Peng X

Published 13 March 2008 Volume 2008:2 Pages 67—77

DOI https://doi.org/10.2147/PPA.S2940



Haya Ascher-Svanum1, Baojin Zhu1, Douglas E Faries1, Jonathan P Lacro2, Christian R Dolder3, Xiaomei Peng1

1Eli Lilly and Company, Outcomes Research, Indianapolis, IN, USA; 2VA San Diego Health Care System and Department of Psychiatry, University of California, San Diego, CA, USA; 3Wingate University School of Pharmacy, Wingate, NC, USA

Objective: To compare adherence and persistence to typical versus atypical antipsychotics and between specific atypical agents in the usual care of schizophrenia and to examine the association between adherence and persistence.

Method: Data were drawn from a 3-year prospective, nonrandomized, noninterventional study of schizophrenia conducted during 1997–2003. Initiators on haloperidol, risperidone, olanzapine, quetiapine, and clozapine with at least 1 year of follow-up were included (n = 878). Adherence (Medication Possession Ratio, MPR) and persistence (time to all-cause medication discontinuation) were assessed using medical record prescription information. Analyses employed multivariate statistics adjusted for group differences.

Results: Overall, 58% of the patients were deemed adherent (MPR >80%). Adherence rates were higher: for atypical (59.4%) than typical antipsychotics (34.5%, p < 0.001), for clozapine (77%) than each comparator excluding olanzapine (p < 0.01), and for olanzapine (64%) than risperidone (57%, p = 0.027) and quetiapine (52%, p = 0.019). Differences between risperidone and quetiapine were not statistically significant. Adherence and persistence were highly correlated (r = 0.957, p < 0.001).

Conclusion: In the usual care of schizophrenia, medication adherence and persistence appear to be highly correlated and to significantly differ between typical and atypical antipsychotics and among atypical agents. The choice of antipsychotic may play a meaningful role in patients’ adherence to and persistence with antipsychotic medications.

Keywords: adherence, persistence, schizophrenia, antipsychotics

Creative Commons License © 2008 The Author(s). This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.