Risk of discontinuation of atypical antipsychotic agents in the treatment of schizophrenia

OBJECTIVES: To compare discontinuation rates of atypical antipsychotic agents in patients with schizophrenia. METHOD: Adult Maryland Medicaid patients with schizophrenia were categorized based on initial atypical antipsychotic drug received: aripiprazole (n=446); olanzapine (n=1705); quetiapine (n=1467); risperidone (n=1580); and ziprasidone (n=700). Discontinuation was measured using refill patterns, allowing 14-day gaps between refill dates. Using olanzapine as the reference drug, the hazard of discontinuation within the first year of follow-up was compared across atypicals using Cox proportional hazard models adjusted for demographic and clinical covariates. Sensitivity analysis tested the robustness of results by using different definitions of the index date. RESULTS: At one-year follow-up, most patients discontinued their antipsychotic medication (90.4% adjusted mean discontinuation). The hazard ratio (HR) for discontinuing therapy in patients starting treatment on aripiprazole, risperidone, or ziprasidone was not significantly different from olanzapine [HR 1.047, 0.973 and 0.990, respectively]. Quetiapine was associated with significantly higher hazard of discontinuation [HR 1.130] than olanzapine. Covariates associated with significantly lower discontinuation were being male [HR 0.899], older age [HR 0.997] and being on concurrent medication when initiating therapy [HR 0.225]; having a previous hospitalization was associated with significantly higher discontinuation hazard [HR 1.276]. Results were robust in the sensitivity analysis. CONCLUSIONS: Discontinuation rates were high at one-year follow-up and did not differ significantly for patients on aripiprazole, olanzapine, risperidone, or ziprasidone. The higher hazard of discontinuation associated with quetiapine when compared to olanzapine is consistent with that observed in Phase I of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE).     

The effectiveness of antipsychotic medications in patients who use or avoid illicit substances: results from the CATIE study

OBJECTIVE: This double-blind study compared a second generation (atypical) antipsychotic drugs compared to a representative older agent for patients with schizophrenia who use or avoid illicit substances. METHODS: Schizophrenic subjects were recruited at 57 U.S. sites and randomly assigned to olanzapine, perphenazine, quetiapine, risperidone or ziprasidone for up to 18 months. The primary aim of this analysis was to delineate differences between the overall effectiveness of these five treatments among patients who used or did not use illicit substances. RESULTS: There were no significant differences between treatment groups in time to all-cause treatment discontinuation among patients who use illicit drugs (median 3.3 to 6.8 months). Among non-users time to treatment discontinuation was significantly longer for patients treated with olanzapine (median 13.0 months) than perphenazine ( 5.9 months), risperidone (5.6 months), or quetiapine (5.0 months); time to discontinuation for ziprasidone (4.3 months) was even shorter, although the latter difference was not significant. The difference between risperidone and quetiapine, although small, was significant. All remaining differences were non-significant. Similar results were found for discontinuation due to inefficacy. There were no differences between illicit users and non-users in symptom reduction and global improvement, after adjustment for differential duration of treatment. Differences in discontinuation results were attenuated by non-compliance, but the trends persisted after controlling for treatment compliance. CONCLUSIONS: Among patients with chronic schizophrenia who avoid use of illicit drugs, olanzapine was more effective than other antipsychotics as reflected by longer time to all-cause discontinuation, but illicit substance abuse attenuated this advantage, reinforcing the need for concurrent substance abuse treatment.     

Effectiveness of olanzapine, quetiapine, risperidone, and ziprasidone in patients with chronic schizophrenia following discontinuation of a previous atypical antipsychotic

BACKGROUND: In the treatment of schizophrenia, changing antipsychotics is common when one treatment is suboptimally effective, but the relative effectiveness of drugs used in this strategy is unknown. This randomized, double-blind study compared olanzapine, quetiapine, risperidone, and ziprasidone in patients who had just discontinued a different atypical antipsychotic. METHOD: Subjects with schizophrenia (N=444) who had discontinued the atypical antipsychotic randomly assigned during phase 1 of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) investigation were randomly reassigned to double-blind treatment with a different antipsychotic (olanzapine, 7.5-30 mg/day [N=66]; quetiapine, 200-800 mg/day [N=63]; risperidone, 1.5-6.0 mg/day [N=69]; or ziprasidone, 40-160 mg/day [N=135]). The primary aim was to determine if there were differences between these four treatments in effectiveness measured by time until discontinuation for any reason. RESULTS: The time to treatment discontinuation was longer for patients treated with risperidone (median: 7.0 months) and olanzapine (6.3 months) than with quetiapine (4.0 months) and ziprasidone (2.8 months). Among patients who discontinued their previous antipsychotic because of inefficacy (N=184), olanzapine was more effective than quetiapine and ziprasidone, and risperidone was more effective than quetiapine. There were no significant differences between antipsychotics among those who discontinued their previous treatment because of intolerability (N=168). CONCLUSIONS: Among this group of patients with chronic schizophrenia who had just discontinued treatment with an atypical antipsychotic, risperidone and olanzapine were more effective than quetiapine and ziprasidone as reflected by longer time until discontinuation for any reason.     

Ethnicity and prescription patterns for haloperidol, risperidone, and olanzapine

OBJECTIVE: Patients with schizophrenia may respond better to second-generation antipsychotics than to older antipsychotics because of their superior efficacy and safety profiles. However, the reduced likelihood among ethnic minority groups of receiving newer antipsychotics may be associated with reduced medication adherence and health service use, potentially contributing to poor response rates. This study examined whether ethnicity helped predict whether patients with schizophrenia were given a first- or a second-generation antipsychotic, haloperidol versus risperidone or olanzapine, and what type of second-generation antipsychotic was prescribed, risperidone or olanzapine, when other factors were controlled for. METHODS: Texas Medicaid claims were analyzed for persons aged 21 to 65 years with a diagnosis of schizophrenia or schizoaffective disorder who started treatment with olanzapine (N=1875), risperidone (N=982), or haloperidol (N= 726) between January 1, 1997 and August 31, 1998. The association between antipsychotic prescribing patterns among African Americans, Mexican Americans, and whites was assessed by using logistic regression analysis. Covariates included other patient demographic characteristics, region, comorbid mental health conditions, and medication and health care resource use in the 12 months before antipsychotic initiation. RESULTS: The results of the first- versus second-generation antipsychotic analysis indicated that African Americans were significantly less likely than whites to receive risperidone or olanzapine. Although not statistically significant, the odds ratio indicated that Mexican Americans were also less likely to receive risperidone or olanzapine. Ethnicity was not associated with significant differences in the prescribing patterns of risperidone versus olanzapine. CONCLUSIONS: When other factors were controlled for, African Americans were significantly less likely to receive the newer antipsychotics. Among those who received the newer antipsychotics, ethnicity did not affect medication choice.     

Antipsychotic treatment discontinuation in previously untreated patients with schizophrenia: 36-month results from the SOHO study

Data from the 3-year, prospective, observational SOHO study were used to compare the effectiveness (in terms of treatment discontinuation) and the tolerability of olanzapine, risperidone, other atypicals and typical antipsychotics in 1009 previously untreated outpatients with schizophrenia who started monotherapy at baseline. Kaplan-Meier survival analysis estimated the time to treatment discontinuation by the treatment group, Cox proportional hazards regression models identified the variables associated with treatment discontinuation (adjusted for baseline differences between treatment groups), and logistic regression models compared the tolerability profiles of the different treatment groups. Of the 931 patients analyzed, 31.9% discontinued the medication initiated at baseline during the 3-year follow-up. Olanzapine had the lowest rate of discontinuation (28.9%), followed by other atypical (34.0%), risperidone (36.2%) and typical antipsychotics (44.5%). Compared to olanzapine, risk of treatment discontinuation was higher with typical antipsychotics (hazard ratio [HR] 1.75; 95% confidence interval [CI] 1.11, 2.78) or risperidone (HR 1.36; 95% CI 1.02, 1.82). A higher baseline Clinical Global Impression (CGI) positive score was associated with a higher risk of treatment discontinuation (HR 1.18; 95% CI 1.06, 1.30). Olanzapine was associated with a lower frequency of extrapyramidal symptoms than other antipsychotics, fewer prolactin-related adverse events than risperidone and other atypical antipsychotics, but greater weight gain than typicals and risperidone. For all analyses, comparison with the other atypical group is limited due to its small sample size (n = 50). In conclusion, treatment effectiveness and tolerability varied among antipsychotic medications in previously untreated patients with schizophrenia. The results should be interpreted conservatively given the observational study design.     

Service use and costs of treating schizophrenia with atypical antipsychotics

BACKGROUND: The high acquisition cost of the atypical antipsychotics has prompted their closer clinical and economic evaluation. This study aims to examine the financial implications of using atypical antipsychotics in a defined catchment area sample of patients with schizophrenia. METHOD: Service costs over a 10-month period were compared between groups of patients fulfilling DSM-IV criteria for schizophrenia who were taking different atypical antipsychotic agents. RESULTS: All patients studied were taking clozapine (N = 31). risperidone (N = 19), or olanzapine (N = 41). Clozapine was used in more chronic patients, while risperidone and olanzapine were prescribed in both chronic and recently diagnosed cases. After background group differences were controlled for, patients on risperidone treatment incurred the lowest costs. The monthly costs for the clozapine and olanzapine groups were higher than for risperidone by US $246 and US $566, respectively. CONCLUSION: Clozapine was reserved for more severe forms of schizophrenia, but its cost impact was relatively low. Risperidone, as prescribed in ordinary practice, may be more cost-effective than olanzapine.     

Antipsychotic use in the treatment of outpatients with schizophrenia in the VA from fiscal years 1999 to 2006

OBJECTIVE: This study examined changes in prescribing patterns of antipsychotic medications to treat schizophrenia. METHODS: Pharmacy records for patients with schizophrenia were obtained from Department of Veterans Affairs databases. The proportion of patients prescribed specific second-generation antipsychotics or any first-generation antipsychotic was calculated per year. RESULTS: In fiscal year (FY) 2006, 78,849 veterans with schizophrenia were prescribed antipsychotic medication. For FY 1999 to FY 2006 the percentage of patients with schizophrenia who received first-generation antipsychotics decreased from 40.8% to 15.9%, but the percentage receiving olanzapine, after peaking at 32.0% in FY 2001, decreased to 19.0%. The percentage of patients given quetiapine increased from 2.5% to 18.8%; risperidone, from 25.5% to 29.7%. However, clozapine usage remained flat, at 2.0%-3.0%. Use of then-new ziprasidone and aripiprazole rose from 5.0% to 9.0%. CONCLUSIONS: Use of each antipsychotic newly marketed over eight years increased while use of risperidone was unchanged and use of olanzapine and the first-generation antipsychotics declined.     

Effectiveness of olanzapine, quetiapine, and risperidone in patients with chronic schizophrenia after discontinuing perphenazine: a CATIE study

OBJECTIVE: The relative effectiveness of newly started antipsychotic drugs for individuals with schizophrenia may depend on multiple factors, including each patient's previous treatment response and the reason for a new medication trial. This randomized, double-blind study compared olanzapine, quetiapine, and risperidone in patients who had just discontinued the older antipsychotic perphenazine. METHOD: Subjects with schizophrenia (N=114) who had been randomly assigned to and then discontinued perphenazine in phase 1 of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) schizophrenia study were reassigned randomly to double-blinded treatment with olanzapine, 7.5-30.0 mg/day (N=38); quetiapine, 200-800 mg/day (N=38); or risperidone, 1.5-6.0 mg/day (N=38). The primary aim was to determine whether there were differences among these three treatments in effectiveness, as measured by time to treatment discontinuation for any reason. Secondary outcomes included reasons for treatment discontinuation and measures of drug tolerability. RESULTS: The time to treatment discontinuation was longer for patients treated with quetiapine (median, 9.9 months) and olanzapine (7.1 months) than with risperidone (3.6 months). There were no significant differences between treatments on discontinuation due to inefficacy, intolerability, or patient decision. CONCLUSIONS: Among this group of patients with chronic schizophrenia who had just discontinued the older antipsychotic perphenazine, quetiapine and olanzapine were more effective than risperidone, as reflected by longer time to discontinuation for any reason. In the context of other results from the CATIE study, the effectiveness and acceptability of antipsychotic drugs appears to vary considerably according to clinical circumstances.     

Comparative effectiveness of second-generation antipsychotic medications in early-onset schizophrenia

Scant information exists to guide pharmacological treatment of early-onset schizophrenia. We examine variation across commonly prescribed second-generation antipsychotic medications in medication discontinuation and psychiatric hospital admission among children and adolescents clinically diagnosed with schizophrenia. A 45-state Medicaid claims file (2001-2005) was analyzed focusing on outpatients, aged 6-17 years, diagnosed with schizophrenia or a related disorder prior to starting a new episode of antipsychotic monotherapy with risperidone (n = 805), olanzapine (n = 382), quetiapine (n = 260), aripiprazole (n = 173), or ziprasidone (n = 125). Cox proportional hazard regressions estimated adjusted hazard ratios of 180-day antipsychotic medication discontinuation and 180-day psychiatric hospitalization for patients treated with each medication. During the first 180 days following antipsychotic initiation, most youth treated with quetiapine (70.7%), ziprasidone (73.3%), olanzapine (73.7%), risperidone (74.7%), and aripirazole (76.5%) discontinued their medication (χ(2) = 1.69, df = 4, P = .79). Compared with risperidone, the adjusted hazards of antipsychotic discontinuation did not significantly differ for any of the 4-comparator medications. The percentages of youth receiving inpatient psychiatric treatment while receiving their initial antipsychotic medication ranged from 7.19% (aripiprazole) to 9.89% (quetiapine) (χ(2) = 0.79, df = 4, P = .94). As compared with risperidone, the adjusted hazard ratio of psychiatric hospital admission was 0.96 (95% CI: 0.57-1.61) for olanzapine, 1.03 (95% CI: 0.59-1.81) for quetiapine, 0.85 (95% CI: 0.43-1.70) for aripiprazole, and 1.22 (95% CI: 0.60-2.51) for ziprasidone. The results suggest that rapid antipsychotic medication discontinuation and psychiatric hospital admission are common in the community treatment of early-onset schizophrenia. No significant differences were detected in risk of either adverse outcome across 5 commonly prescribed second-generation antipsychotic medications.     

Effectiveness of clozapine versus olanzapine, quetiapine, and risperidone in patients with chronic schizophrenia who did not respond to prior atypical antipsychotic treatment

OBJECTIVE: When a schizophrenia patient has an inadequate response to treatment with an antipsychotic drug, it is unclear what other antipsychotic to switch to and when to use clozapine. In this study, the authors compared switching to clozapine with switching to another atypical antipsychotic in patients who had discontinued treatment with a newer atypical antipsychotic in the context of the Clinical Antipsychotic Trials for Interventions Effectiveness (CATIE) investigation. METHOD: Ninety-nine patients who discontinued treatment with olanzapine, quetiapine, risperidone, or ziprasidone in phase 1 or 1B of the trials, primarily because of inadequate efficacy, were randomly assigned to open-label treatment with clozapine (N=49) or blinded treatment with another newer atypical antipsychotic not previously received in the trial (olanzapine [N=19], quetiapine [N=15], or risperidone [N=16]). RESULTS: Time until treatment discontinuation for any reason was significantly longer for clozapine (median=10.5 months) than for quetiapine (median=3.3), or risperidone (median=2.8), but not for olanzapine (median=2.7). Time to discontinuation because of inadequate therapeutic effect was significantly longer for clozapine than for olanzapine, quetiapine, or risperidone. At 3-month assessments, Positive and Negative Syndrome Scale total scores had decreased more in patients treated with clozapine than in patients treated with quetiapine or risperidone but not olanzapine. One patient treated with clozapine developed agranulocytosis, and another developed eosinophilia; both required treatment discontinuation. CONCLUSIONS: For these patients with schizophrenia who prospectively failed to improve with an atypical antipsychotic, clozapine was more effective than switching to another newer atypical antipsychotic. Safety monitoring is necessary to detect and manage clozapine's serious side effects.     

Effects of atypical and typical antipsychotic treatments on sexual function in patients with schizophrenia: 12-month results from the Intercontinental Schizophrenia Outpatient Health Outcomes (IC-SOHO) study.

PURPOSE: Sexual dysfunction in patients with schizophrenia can reduce quality of life and treatment compliance. This report will compare the effects of selected atypical and typical antipsychotics on sexual function in a large, international population of outpatients with schizophrenia who were treated over 1 year. SUBJECTS AND METHODS: Outpatients with schizophrenia, who initiated or changed antipsychotic treatment, and entered this 3-year, prospective, observational study were classified according to the monotherapy prescribed at baseline: olanzapine (N=2638), risperidone (N=860), quetiapine (N=142) or haloperidol (N=188). RESULTS: Based on patient perception, the odds of experiencing sexual dysfunction during 1 year of therapy was significantly lower for patients treated with olanzapine and quetiapine when compared to patients who received risperidone or haloperidol (all P< or =0.001). Females on olanzapine (14%) or quetiapine (8%) experienced a lower rate of menstrual irregularities, compared to females on risperidone (23%) or haloperidol (29%). Significant discordance was evident between patient reports and psychiatrist perception of sexual dysfunction, with psychiatrists underestimating sexual dysfunction (P< or =0.001). CONCLUSION: These findings indicate clinically relevant differences exist in the sexual side effect profiles of these selected antipsychotics. These factors should be considered when selecting the most appropriate treatment for outpatients with schizophrenia.     

Incidence of newly diagnosed diabetes attributable to atypical antipsychotic medications

OBJECTIVE: The purpose of the study was to determine the proportion of patients with schizophrenia with a stable regimen of antipsychotic monotherapy who developed diabetes or were hospitalized for ketoacidosis. METHOD: Patients with schizophrenia for whom a stable regimen of antipsychotic monotherapy was consistently prescribed during any 3-month period between June 1999 and September 2000 and who had no diabetes were followed through September 2001 by using administrative data from the Department of Veterans Affairs. Cox proportional hazards models were developed to identify the characteristics associated with newly diagnosed diabetes and ketoacidosis. RESULTS: Of the 56,849 patients identified, 4,132 (7.3%) developed diabetes and 88 (0.2%) were hospitalized for ketoacidosis. Diabetes risk was highest for clozapine (hazard ratio=1.57) and olanzapine (hazard ratio=1.15); the diabetes risks for quetiapine (hazard ratio=1.20) and risperidone (hazard ratio=1.01) were not significantly different from that for conventional antipsychotics. The attributable risks of diabetes mellitus associated with atypical antipsychotics were small, ranging from 0.05% (risperidone) to 2.03% (clozapine). CONCLUSIONS: Although clozapine and olanzapine have greater diabetes risk, the attributable risk of diabetes mellitus with atypical antipsychotics is small.     

Clozapine, olanzapine, risperidone, and haloperidol in the treatment of patients with chronic schizophrenia and schizoaffective disorder

OBJECTIVE: The authors compared the efficacy and safety of three atypical antipsychotics (clozapine, olanzapine, and risperidone) with one another and with haloperidol in the treatment of patients with chronic schizophrenia or schizoaffective disorder. METHOD: In a double-blind trial, 157 inpatients with a history of suboptimal treatment response were randomly assigned to treatment with clozapine, olanzapine, risperidone, or haloperidol for 14 weeks (an 8-week escalation and fixed-dose period followed by a 6-week variable-dose period). RESULTS: Clozapine, risperidone, and olanzapine (but not haloperidol) resulted in statistically significant improvements in total score on the Positive and Negative Syndrome Scale. Improvements seen in total and negative symptom scores with clozapine and olanzapine were superior to haloperidol. The atypical drugs, particularly olanzapine and clozapine, were associated with weight gain. CONCLUSIONS: The effects of atypical antipsychotics in this population were statistically significant but clinically modest. The overall pattern of results suggests that clozapine and olanzapine have similar general antipsychotic efficacy and that risperidone may be somewhat less effective. Clozapine was the most effective treatment for negative symptoms. However, the differences among treatments were small.     

The Schizophrenia Outpatient Health Outcomes (SOHO) study: 3-year results of antipsychotic treatment discontinuation and related clinical factors in Spain.

INTRODUCTION: This article presents the long-term results in terms of antipsychotic medication maintenance and factors influencing it in a representative sample of patients with schizophrenia recruited in the SOHO study within Spain. METHODS: The SOHO was a prospective, 3-year observational study of the outcomes of schizophrenia treatment in outpatients who initiated therapy or changed to a new antipsychotic performed in 10 European countries with a focus on olanzapine. The Kaplan-Meier method was used to analyse the time to treatment discontinuation and the Cox proportional hazards model to investigate correlates of discontinuation. RESULTS AND CONCLUSIONS: In total, 1688 patients were included in the analyses. Medication maintenance at 3years varied with the antipsychotic prescribed, being highest with clozapine (57.6%, 95% CI 39.2-74.5), followed by olanzapine (48.3%, 95% CI 45.1-51.5); and lowest with quetiapine (19.0%, 95% CI 13.0-26.3). Treatment discontinuation was significantly less frequent with olanzapine than with risperidone (p=0.015), depot typical (p=0.001), oral typical antipsychotics (p<0.001) or quetiapine (p<0.001); but not than with clozapine (p=0.309). Longer maintenance was also associated with higher social abilities and better cognitive status at baseline; in contrast, a shorter time to discontinuation was associated with the need for mood stabilisers during follow-up. This study emphasises the different value of antipsychotics in day-to-day clinical practice, as some of them were associated with longer medication maintenance periods than others. This study has some limitations because of possible selection and information biases derived from the non-systematic, non-randomised allocation to treatments and the existence of unobserved covariates that may influence the outcome.     

Treatment with olanzapine, risperidone or typical antipsychotic drugs in Asian patients with schizophrenia

OBJECTIVE: To examine clinical outcomes in Asian patients with schizophrenia receiving monotherapy with olanzapine, risperidone or typical antipsychotics in naturalistic settings. METHOD: In this report, data from the first 12 months of the prospective, observational, 3-year Intercontinental Schizophrenia Outpatient Health Outcomes study are presented for patients from participating Asian countries (Korea, Taiwan and Malaysia) who were started on, or switched to, monotherapy with olanzapine (n = 484), risperidone (n = 287) or a typical antipsychotic drug (n = 127) at baseline. RESULTS: At 12 months, overall reduction in the score of Clinical Global Impressions-Severity of Illness rating scale was greatest with olanzapine (p < 0.001 vs typical agents), followed by risperidone (p = 0.007 vs typical agents) treatment. Olanzapine treatment was found to have significantly better effects than typical agents on negative and depressive symptom scores, and significantly greater improvements than risperidone on negative and cognitive symptoms. The occurrence of extrapyramidal symptoms was least likely with olanzapine (p < 0.001 vs typical agents, and p = 0.012 vs risperidone), while the estimated odds of tardive dyskinesia were greatest in the typical treatment group (p = 0.046 vs olanzapine, and p = 0.082 vs risperidone). Mean weight increase was greater for olanzapine-treated patients compared with the other agents (p = 0.030 vs typical agents and p < 0.001 vs risperidone). The risk of menstrual disturbance was relatively high with risperidone when compared with olanzapine treatment (p < 0.001). CONCLUSIONS: The results of this observational study indicate that, in Asian patients with schizophrenia, olanzapine may offer benefits when compared with typical agents or risperidone. However, the significantly greater odds of weight gain should be considered in the clinical management of olanzapine-treated patients.