Patient characteristics and the likelihood of initiation on olanzapine or risperidone among patients with schizophrenia
ABSTRACT Although pharmacologic treatments are available for patients with schizophrenia, little is known about how prescription patterns of atypical antipsychotic agents are related to patient characteristics. In this study, we examined the association between patient characteristics and the likelihood of being initiated on olanzapine or risperidone, two of the most frequently prescribed atypical agents for schizophrenia. We selected patients who were diagnosed with schizophrenia or schizoaffective disorder based on > or = 1 inpatient or > or = 2 outpatient ICD-9-CM codes (> or = 7 days apart) between 7/1/98 and 6/30/99 from the Veterans Health Administration (VA). We classified patients into one of three types of initiation: (a) not on olanzapine or risperidone, (b) not on any atypical agents, or (c) not on any antipsychotic agents for 6 months, and then subsequently being prescribed the target drugs. Using logistic regression, we examined whether the odds ratio of being initiated on olanzapine versus risperidone are related to patient sociodemographic and clinical characteristics. Compared to risperidone initiators, olanzapine initiators used more drugs for psychiatric conditions (including antiparkinsonian agents, typical antipsychotics, and mood stabilizers) than risperidone initiators. On the other hand, risperidone initiators had more medical comorbidities and more non-psychiatric hospitalizations. Olanzapine and risperidone appear to be prescribed to patients with different characteristics. Initiation of risperidone was more common among patients who presented with more medical comorbid conditions, whereas initiation of olanzapine was more common among patient who presented with more mental comorbid conditions. Future research needs to determine the reasons for those differences.
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ABSTRACT: The importance of medication adherence in sustaining control of schizophrenic symptoms has generated a great deal of interest in comparing levels of treatment adherence with different antipsychotic agents. However, the bulk of the research has yielded results that are often inconsistent. In this prospective, observational study, we assessed the measurement properties of 3 commonly used, pharmacy-based measures of treatment adherence with antipsychotic agents in schizophrenia using data from the Veterans Health Administration during 2000 to 2005. Patients were selected if they were on antipsychotics and diagnosed with schizophrenia (N = 18,425). A gap of >/=30 days (with no filled index medication) was used to define discontinuation of treatment as well as medication "episodes," or the number of times a patient returned to the same index agent after discontinuation of treatment within a 1-year period. The study found that the 3 existing measures differed in their approaches in measuring treatment adherence, suggesting that studies using these different measures would generate different levels of treatment adherence across antipsychotic agents. Considering the measurement problems associated with each existing approach, we offered a new, medication episode-specific approach, which would provide a fairer comparison of the levels of treatment adherence across different antipsychotic agents.Neuropsychiatric Disease and Treatment 10/2009; 5:491-8. · 2.15 Impact Factor
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ABSTRACT: Treatment guidelines suggest distinctive medication strategies for first-episode and multiepisode patients with schizophrenia. To assess the extent to which community clinicians adjust their usual treatment regimens for first-episode patients, the authors examined prescription patterns and factors associated with prescription choice in a national cohort of early-phase patients. Prescription data at study entry were obtained from 404 participants in the Recovery After an Initial Schizophrenia Episode Project's Early Treatment Program (RAISE-ETP), a nationwide multisite effectiveness study for patients with first-episode schizophrenia spectrum disorders. Treatment with antipsychotics did not exceed 6 months at study entry. The authors identified 159 patients (39.4% of the sample) who might benefit from changes in their psychotropic prescriptions. Of these, 8.8% received prescriptions for recommended antipsychotics at higher than recommended dosages; 32.1% received prescriptions for olanzapine (often at high dosages), 23.3% for more than one antipsychotic, 36.5% for an antipsychotic and also an antidepressant without a clear indication, 10.1% for psychotropic medications without an antipsychotic, and 1.2% for stimulants. Multivariate analysis showed evidence for sex, age, and insurance status effects on prescription practices. Racial and ethnic effects consistent with effects reported in previous studies of multiepisode patients were found in univariate analyses. Despite some regional variations in prescription practices, no region consistently had different practices from the others. Diagnosis had limited and inconsistent effects. Besides prescriber education, policy makers may need to consider not only patient factors but also service delivery factors in efforts to improve prescription practices for first-episode schizophrenia patients.American Journal of Psychiatry 03/2015; 172(3):237-48. DOI:10.1176/appi.ajp.2014.13101355 · 13.56 Impact Factor
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ABSTRACT: Prior investigations suggest that olanzapine use declined rapidly after a U.S. Food and Drug Administration (FDA) communication and consensus statement warning of the drug's increased metabolic risks, but whether declines differed by racial-ethnic groups is unknown. Changes in olanzapine use over time by race-ethnicity was assessed among 7,901 Florida Medicaid enrollees with schizophrenia. Prior to the advisory, 57% of second-generation antipsychotic fills among Hispanics were for olanzapine, compared with 40% for whites or blacks (adjusted risk difference [ARD]=.17, 95% confidence interval [CI]=.13-.20). Olanzapine use declined among all racial-ethnic groups. Although Hispanics had greater olanzapine use than whites in each period, the differences in absolute risk were only 3% by the latest study period (ARD=.03, CI=.01-.04). After the FDA communication and consensus statement were issued, differences in olanzapine use between white and Hispanic enrollees narrowed considerably. Identifying high-use subgroups for targeted delivery of drug safety information may help eliminate any existing differences in prescribing.Psychiatric services (Washington, D.C.) 01/2013; 64(1):83-7. DOI:10.1176/appi.ps.201200002 · 1.99 Impact Factor