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.     

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.     

Serum leptin and triglyceride levels in patients on treatment with atypical antipsychotics

BACKGROUND: Weight gain is a common adverse effect associated with the use of most antipsychotic drugs. Leptin has been reported to be associated with antipsychotic-induced weight gain. Previous studies have demonstrated a relationship between the atypical antipsychotics clozapine and olanzapine and serum leptin levels. We planned to comparatively investigate the effects of the atypical antipsychotics quetiapine, olanzapine, risperidone, and clozapine on leptin and triglyceride levels and weight gain. METHOD: The study population comprised 56 patients with DSM-IV schizophrenia, who were divided into 4 treatment groups: quetiapine (N = 14), olanzapine (N = 14), risperidone (N = 14), or clozapine (N = 14) monotherapy, and a control group of 11 patients receiving no psychopharmacologic treatment. The patients were evaluated at baseline and at the sixth week according to the Positive and Negative Syndrome Scale (PANSS), body mass index (BMI), weight, and fasting serum leptin and triglyceride levels. Data were gathered in 2001 and 2002. RESULTS: Olanzapine and clozapine caused a marked increase in weight and serum triglyceride and leptin levels, though increases in these variables were modest in the patients receiving quetiapine and minimal in those receiving risperidone. There were positive correlations between serum leptin levels and BMI and triglyceride levels. Clinical efficacy, as indicated by decrease in total PANSS scores, was associated with leptin levels in all atypical antipsychotic groups. CONCLUSION: Our results suggest that leptin may be associated with olanzapine- and clozapine-induced weight gain and that quetiapine appears to have modest influence and risperidone appears to have minimal influence on leptin and triglyceride levels and weight gain compared with olanzapine and clozapine.     

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).     

Effect of switching to atypical antipsychotics on memory in patients with chronic schizophrenia

While the usefulness of atypical antipsychotics for improving cognitive function has been proven, the specific effects of these drugs are still unknown. The objective of this study was to investigate changes of the immediate memory and verbal working memory in patients with chronic schizophrenia after switching to one of four atypical antipsychotic agents and cessation of anticholinergic therapy. The subjects included 77 schizophrenic patients who were treated primarily with typical antipsychotics. Treatment was randomly switched to one of four atypical antipsychotics (olanzapine, perospirone, quetiapine, or risperidone) over a 4-week period, and then the drug was continued for another 4 weeks while the patient was taken off anticholinergics. The immediate memory, verbal working memory, and symptoms were evaluated. Significant improvement of immediate memory was only seen with olanzapine and risperidone. Improvement was also seen after switching to perospirone, but immediate memory worsened after treatment with this anticholinergic drug was discontinued. Deterioration was seen after switching to quetiapine, but immediate memory improved and reached the previous level after treatment with anticholinergic drugs was discontinued. Significant improvement of the verbal working memory was only seen during risperidone administration. The findings suggested that switching chronic schizophrenic patients to atypical antipsychotics can improve both the immediate memory and the verbal working memory when risperidone is used, while improvement of immediate memory can be expected with olanzapine. From the viewpoint of improving the memory, quetiapine should not be administered concomitantly with anticholinergic drugs, and caution should be exercised when discontinuing anticholinergic drugs during treatment with perospirone.     

Quetiapine in the treatment of focal tardive dystonia induced by other atypical antipsychotics: a report of 2 cases

The authors report 2 patients with schizophrenia who developed focal tardive dystonia secondary to treatment with atypical antipsychotics (risperidone, olanzapine). When quetiapine was gradually introduced and other antipsychotics were discontinued, these patients experienced remarkable and sustained improvement of their dystonic symptoms, without loss of psychotic symptom control. The mechanism by which quetiapine may improve tardive dystonia caused by other atypical antipsychotics is unclear. Due to its receptor and pharmacologic profile, quetiapine is the atypical antipsychotic that is most similar to clozapine (without its hematologic side effects), which leads the authors to consider it for the treatment of tardive movement disorders.     

Equivalent occupancy of dopamine D1 and D2 receptors with clozapine: differentiation from other atypical antipsychotics

OBJECTIVE: Clozapine, the prototype of atypical antipsychotics, remains unique in its efficacy in the treatment of refractory schizophrenia. Its affinity for dopamine D(4) receptors, serotonin 5-HT(2A) receptor antagonism, effects on the noradrenergic system, and its relatively moderate occupancy of D(2) receptors are unlikely to be the critical mechanism underlying its efficacy. In an attempt to elucidate the molecular/synaptic mechanism underlying clozapine's distinctiveness in refractory schizophrenia, the authors studied the in vivo D(1) and D(2) receptor profile of clozapine compared with other atypical antipsychotics. METHOD: Positron emission tomography with the radioligands [(11)C]SCH23390 and [(11)C]raclopride was used to investigate D(1) and D(2) receptor occupancy in vivo in 25 schizophrenia patients receiving atypical antipsychotic treatment with clozapine, olanzapine, quetiapine, or risperidone. RESULTS: Mean striatal D(1) occupancies ranged from 55% with clozapine to 12% with quetiapine (rank order: clozapine > olanzapine > risperidone > quetiapine). The striatal D(2) occupancy ranged from 81% with risperidone to 30% with quetiapine (rank order: risperidone > olanzapine > clozapine > quetiapine). The ratio of striatal D(1)/D(2) occupancy was significantly higher for clozapine (0.88) relative to olanzapine (0.54), quetiapine (0.41), or risperidone (0.31). CONCLUSIONS: Among the atypical antipsychotics, clozapine appears to have a simultaneous and equivalent occupancy of dopamine D(1) and D(2) receptors. Whether its effect on D(1) receptors represents agonism or antagonism is not yet clear, as this issue is still unresolved in the preclinical arena. This distinctive effect on D(1)/D(2) receptors may be responsible for clozapine's unique effectiveness in patients with schizophrenia refractory to other typical and atypical antipsychotics.     

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.     

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.     

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.     

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.     

Effects of changing from typical to atypical antipsychotic drugs on subjective sleep quality in patients with schizophrenia in a Japanese population

OBJECTIVE: To investigate the effects of the atypical antipsychotic drugs risperidone, olanzapine, quetiapine, and perospirone on the subjective quality of sleep in patients with schizophrenia. METHOD: Subjects were 92 inpatients (mean age = 59.9 years) who had been receiving treatment with conventional antipsychotic drugs and who met the DSM-IV criteria for schizophrenia. Subjects were randomly assigned to receive 1 of 4 atypical antipsychotic drugs (olanzapine, perospirone, quetiapine, and risperidone). Subjective sleep quality and psychopathology were assessed twice: at baseline and 8 weeks after switching. Data were collected from June 2001 to December 2001. Subjective sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI), and psychopathology was measured by the Positive and Negative Syndrome Scale (PANSS). RESULTS: Subjective sleep quality as assessed by the PSQI was significantly improved with administration of olanzapine, risperidone, or quetiapine, but not with perospirone, in comparison with conventional antipsychotic drugs. Multiple regression analysis revealed that the improvement of sleep quality with administration of atypical antipsychotic drugs was predicted by poor sleep quality at baseline. In addition, improvement of sleep quality was significantly correlated with improvement of negative symptoms as assessed by the PANSS. CONCLUSION: These results demonstrated that atypical antipsychotic drugs improved subjective quality of sleep in patients with schizophrenia compared with conventional antipsychotic drugs, suggesting that the marked potency of serotonin-2 receptor blockade in atypical antipsychotic drugs may be involved in the mechanism of this improvement. These improvements were correlated with improvement of negative symptoms.     

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.     

Resource utilization in a Canadian national study of people with schizophrenia and related psychotic disorders

OBJECTIVE: To determine how the use of the newer, so called atypical antipsychotic medications, effects the pharmacoeconomic treatment burden of schizophrenia and related conditions and to provide a clear comparison of the costs and risks associated with these atypical drugs. METHOD: In this 2-year, open-label, prospective study, resource utilization (RU) data were collected on 160 patients with these conditions. A comparison between risks and costs was performed by combining the generalized CNOMSS data on both economic factors and risk assessments. RESULTS: The main findings of the study were that the total adjusted 1- and 2-year costs were lowest for quetiapine. Drug acquisition costs were lowest for risperidone for both the 1- and 2-year cohorts. Clozapine use was predictably associated with the highest overall and medication costs at both 1 and 2 years. CONCLUSION: Treatment with risperidone or quetiapine was associated with the lowest overall costs when compared with olanzapine or clozapine.     

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.     

Effectiveness of clozapine, olanzapine, quetiapine, risperidone, and haloperidol monotherapy in reducing hostile and aggressive behavior in outpatients treated for schizophrenia: a prospective naturalistic study (IC-SOHO).

OBJECTIVE: Antipsychotic medications may reduce hostile and aggressive behavior in schizophrenia. This study compared the effectiveness of antipsychotics in the treatment of aggression. METHOD: The Intercontinental Schizophrenia Outpatient Health Outcomes (IC-SOHO) study compares the effectiveness of antipsychotic treatments in practice setting. Schizophrenia outpatients who initiated or changed to a new antipsychotic are followed in this non-interventional, prospective observational study for up to 3 years, with 6-months data now available on the entire cohort (N=7655). The presence or absence of verbal or physical hostility/aggression was assessed retrospectively for the period of 6 months before enrollment, and prospectively in the period of 6 months after enrollment (the study treatment period). At baseline, patients in five monotherapy treatment groups (combined N=3135) were prescribed one of the treatments: clozapine, olanzapine, quetiapine, risperidone, or haloperidol, and had complete data. RESULTS: Hostile/aggressive behavior was reduced during the treatment period. Olanzapine and risperidone were significantly superior to haloperidol and to clozapine in this respect. These results remained essentially unchanged when adjusting for baseline imbalances in age, gender, age of onset, and substance abuse. CONCLUSIONS: As monotherapy, both olanzapine and risperidone were superior to haloperidol and clozapine in reducing aggression. The relative lack of effectiveness of clozapine may be specific to this study population.     

Neurocognitive effects of clozapine,olanzapine, risperidone,and haloperidol in patients with chronic schizophrenia or schizoaffective disorder

OBJECTIVE: Newer antipsychotic drugs have shown promise in ameliorating neurocognitive deficits in patients with schizophrenia, but few studies have compared newer antipsychotic drugs with both clozapine and conventional agents, particularly in patients who have had suboptimal response to prior treatments. METHOD: The authors examined the effects of clozapine, olanzapine, risperidone, and haloperidol on 16 measures of neurocognitive functioning in a double-blind, 14-week trial involving 101 patients. A global score was computed along with scores in four neurocognitive domains: memory, attention, motor function, and general executive and perceptual organization. RESULTS: Global neurocognitive function improved with olanzapine and risperidone treatment, and these improvements were superior to those seen with haloperidol. Patients treated with olanzapine exhibited improvement in the general and attention domains but not more than that observed with other treatments. Patients treated with risperidone exhibited improvement in memory that was superior to that of both clozapine and haloperidol. Clozapine yielded improvement in motor function but not more than in other groups. Average effect sizes for change were in the small to medium range. More than half of the patients treated with olanzapine and risperidone experienced "clinically significant" improvement (changes in score of at least one-half standard deviation relative to baseline). These findings did not appear to be mediated by changes in symptoms, side effects, or blood levels of medications. CONCLUSIONS: Patients with a history of suboptimal response to conventional treatments may show cognitive benefits from newer antipsychotic drugs, and there may be differences between atypical antipsychotic drugs in their patterns of cognitive effects.     

The PsyCoLaus study: methodology and characteristics of the sample of a population-based survey on psychiatric disorders and their association with genetic and cardiovascular risk factors

Background

How long an antipsychotic is effective in maintaining response is important in choosing the correct treatment for people with schizophrenia. This post-hoc analysis describes maintenance of response over 24 or 28 weeks in people treated for schizophrenia with olanzapine, risperidone, quetiapine, ziprasidone, or aripiprazole.

Methods

This was a post-hoc analysis using data from 5 double-blind, randomized, comparative trials of 24 or 28 weeks duration in which olanzapine was compared to risperidone (1 study; N = 339), quetiapine (1 study; N = 346), ziprasidone (2 studies; N = 548 and 394) or aripiprazole (1 study; N = 566) for treatment of schizophrenia. For each study, time to loss of response in patients who met criteria for response at Week 8 and the proportion of patients who lost response following Week 8 were compared by treatment group. The number needed to treat (NNT) with olanzapine rather than comparator to avoid loss of one additional responder over 24 or 28 weeks of treatment was calculated for each study.

Results

Time maintained in response was significantly longer (p < .05) for olanzapine compared to risperidone, quetiapine, and ziprasidone. Olanzapine did not significantly differ from aripiprazole. The proportion of patients who lost response was significantly lower for olanzapine versus risperidone, quetiapine, and ziprasidone (p < .05). NNTs to avoid one additional patient with loss of response with olanzapine versus risperidone, quetiapine and ziprasidone were favourable, ranging from 5 to 9.

Conclusion

During 24 and 28 weeks of treatment, the antipsychotics studied differed in the time that treated patients with schizophrenia remained in response and the proportion of patients who lost response. Olanzapine treatment resulted in a consistent and statistically significant advantage in maintenance of response compared to treatment with risperidone, quetiapine and ziprasidone; but not compared to treatment with aripiprazole.     

Cognitive function and social abilities in patients with schizophrenia: relationship with atypical antipsychotics

Although atypical antipsychotics have been associated with improvements in cognitive function in schizophrenia, the neurochemical basis for such effects is not well understood. Candidate neurotransmitter systems primarily involve dopamine and serotonin. The current study explored this issue by examining the cognitive abilities, social function and quality of life in patients with schizophrenia who were medicated with atypical antipsychotics. Comparisons were done for matched schizophrenia patients who were on antipsychotics with (i) an affinity for multiple receptors (olanzapine, clozapine, quetiapine) versus those that have preferential affinity for dopamine receptors (risperidone, amisulpride); and patients on medication with (ii) a high affinity for serotonin (5HT-2A) receptors (risperidone, olanzapine, clozapine) versus those with a low (or no) affinity for 5HT-2A receptors (quetiapine, amisulpride). No differences emerged between groups on any cognitive or social variable when the groups were compared for the dopaminergic properties of antipsychotic medication. By contrast, differences did emerge when patients were compared on the 5HT-2A affinity of their antipsychotic medications. Patients on low 5HT-2A-affinity antipsychotics exhibited a better performance on a measure of selective attention and adjustment to living. These findings accord with the notion that serotonergic mechanisms are important determinants of both the cognitive and the social effects of the atypical antipsychotics.     

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.