Patient characteristics and the likelihood of initiation on olanzapine or risperidone among patients with schizophrenia

Prescription practices in the treatment of first-episode schizophrenia spectrum disorders: data from the national RAISE-ETP study

OBJECTIVE

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.

METHOD

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.

RESULTS

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.

CONCLUSIONS

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.

Racial-ethnic differences in incident olanzapine use after an FDA advisory for patients with schizophrenia

OBJECTIVE

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.

METHODS

Changes in olanzapine use over time by race-ethnicity was assessed among 7,901 Florida Medicaid enrollees with schizophrenia.

RESULTS

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).

CONCLUSIONS

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.

Relative contribution of antipsychotics, negative symptoms and executive functions to social functioning in stable schizophrenia

The purpose of this study was to examine the relative contributions of antipsychotic medication, negative symptoms and executive functions to impairment in social functioning in a sample of outpatients with stable schizophrenia. One-hundred and sixty-eight consecutive outpatients with stable schizophrenia were enrolled in a cross-sectional study. We performed a path analysis using multiple regression technique in order to assess the specific effect of antipsychotic type (first-generation antipsychotics versus second-generation antipsychotics) on social functioning and the possible mediating role of executive functions and negative symptoms. Our findings suggested that (i) second generation antipsychotics (SGAs) use predicted better social functioning (Beta=.24, p=.003) and better executive functions (Beta=.25, p=.003); conversely SGAs use was not associated with lesser negative symptoms (Beta=.00, p=.981); (ii) impaired executive functions and severity of negative symptoms were associated with worse social functioning (Beta=.19, p=.016; Beta=.28, p=.001); (iii) when we inserted in the model Positive and Negative Syndrome Scale - Negative Symptom subscale (PANSS-N) and Wisconsin Card Sorting Test - number of achieved sorting categories (WCST-cat), the former failed to show a mediation effect, while the latter seemed to mediate partially the effect of SGAs on social functioning. Taken together, the present results suggest that it is critical to examine individually executive functions and negative symptoms because they seem to relate to social functioning in different and independent ways and thus might represent separable treatment targets. Furthermore, social functioning appears a complex outcome multiply determined with no single predictor variable explaining a sufficient amount of variance.

Measurement of treatment adherence with antipsychotic agents in patients with schizophrenia

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.

An alternative approach to measuring treatment persistence with antipsychotic agents among patients with schizophrenia in the Veterans Health Administration

Prior studies have demonstrated the importance of treatment persistence with anti-psychotic agents in sustaining control of schizophrenic symptoms. However, the conventional approach in measuring treatment persistence tended to use only the first prescription episode even though some patients received multiple prescriptions (or multiple treatment episodes) of the same medication within one year following the initiation of the index drug. In this study, we used data from the Veterans Health Administration in the United States to assess the extent to which patients received multiple prescriptions. The study found that about a quarter of the patients had two or more treatment episodes and that levels of treatment persistence tended to vary across treatment episodes. Based on these results, we offered an alternative approach in which we calculated treatment persistence with typical and atypical antipsychotic agents separately for patients with one, two, or three treatment episodes. Considering that patients with different number of treatment episodes might differ in disease profiles, this treatment episode-specific approach offered a fair comparison of the levels of treatment persistence across patients with different number of treatment episodes. Future research needs to extend the analyses beyond two antipsychotic classes to individual antipsychotic agents. A more comprehensive assessment using appropriate analytic methods should help physicians make prescription choices that will ultimately improve the care of patients with schizophrenia.

Treatment persistence: a comparison among patients with schizophrenia who were initiated on atypical antipsychotic agents

BACKGROUND

Although clinical trials have demonstrated the efficacy of atypical antipsychotic agents in reducing symptoms of schizophrenia, the likelihood of sustaining control of schizophrenic symptoms may depend on treatment persistence.

OBJECTIVE

In this study, we compared treatment persistence between patients who were initiated on risperidone or olanzapine, the two most widely prescribed atypical antipsychotic agents.

METHOD

We identified patients with schizophrenia by ICD-9-CM codes (> or =1 inpatient or > or =2 outpatient ICD-9-CM codes > or =7 days apart) between 1 July 1998 and 30 June 1999. We further selected those who were prescribed the target drug during 1 April 1999 through 31 March 2000 provided that they were not on any antipsychotic agents during the prior 6 months. Using event history analysis, we compared the treatment persistence in terms of hazard ratio between olanzapine and risperidone initiators, adjusting for patient's sociodemographic and clinical characteristics.

RESULTS

Following the initiation of the target drug, more patients switched from risperidone to olanzapine than vice versa. However, among patients with schizophrenia who had comorbid diabetes, there were more patients who made a switch from olanzapine to risperidone; whereas among those who used anxiolytics, there were more patients who switched from risperidone to olanzapine. Finally, olanzapine initiators had decreased hazards of discontinuation by 14% (unadjusted; P < 0.001) and 12% (adjusted; P = 0.002), respectively, than risperidone initiators.

CONCLUSIONS

Compared with risperidone, olanzapine seems to be better tolerated by patients as indicated by better treatment persistence. As such, initiation of olanzapine may increase the likelihood of sustaining control of symptoms of schizophrenia. Future research needs to provide a more comprehensive assessment of treatment persistence by considering other antipsychotic agents in the study and developing models to assess treatment persistence and switching as two interdependent competing risks.

How do psychiatrists choose among different antipsychotics?

OBJECTIVE

We attempted to determine the decision rules psychiatrists use in the choice of antipsychotic drugs for inpatients with schizophrenia.

METHODS

Interviews were conducted with 50 hospital psychiatrists in Southern Germany. Each physician was interviewed with respect to the reasons for his antipsychotic drug choice in the cases of three patients with a diagnosis of schizophrenia. Interviews were audiotaped and subsequently analyzed using a standardized coding scheme.

RESULTS

The clinical decision rules identified are highly complex, with a mean of eight categories cited per patient. Categories named included the patient's past treatment response, side effects, intended route of administration and co-morbidities. Moreover, psychiatrists strongly take the patient's target symptoms and the assumed efficacy of certain compounds into account in their choice of medication.

CONCLUSION

Psychiatrists' explanations for their antipsychotic drug choice seem for the most part reasonable and overlap substantially with drug-choice algorithms of clinical guidelines. However, psychiatrists additionally use indicators that--in their view--might predict treatment response. For these indicators, which are derived from personal experience, it is still unclear whether they are valid and simply have not yet been proven in clinical trials or whether they merely represent unfounded assumptions on the part of the doctors.