Olanzapine induces insulin resistance: results from a prospective study

BACKGROUND: The aim of this study was to compare glucose metabolism in patients with schizophrenia receiving olanzapine with that in control subjects. METHOD: We conducted a prospective, controlled, open study comparing body weight, fat mass, and indices of insulin resistance/ sensitivity in 10 olanzapine-treated patients with ICD-10 schizophrenia (olanzapine dose range, 7.5-20 mg/day) with those of a group of 10 mentally and physically healthy volunteers. Weight, fat mass, and indices of insulin resistance/sensitivity were assessed over individual 8-week observation periods from November 1997 to October 1999. RESULTS: Fasting serum glucose and fasting serum insulin increased significantly in the olanzapine-treated patients (p =.008 for glucose and p =.006 for insulin). The homeostasis model assessment (HOMA) index for beta cell function did not change significantly in the olanzapine-treated patients, whereas the HOMA index for insulin resistance did increase (p =.006). In the control group, these parameters were stable. A significant increase in body weight (p =.001) and body fat (p =.004) was seen in patients treated with olanzapine, while the control group showed no significant changes. CONCLUSION: This study indicates that the disturbances in glucose homeostasis during antipsychotic treatment with olanzapine are mainly due to insulin resistance. However, beta cell function remains unaltered in olanzapine-treated patients. We conclude that treatment with some second-generation antipsychotic drugs may lead to insulin resistance.     

Glucose metabolism in patients with schizophrenia treated with atypical antipsychotic agents: a frequently sampled intravenous glucose tolerance test and minimal model analysis

BACKGROUND: While the incidence of new-onset diabetes mellitus may be increasing in patients with schizophrenia treated with certain atypical antipsychotic agents, it remains unclear whether atypical agents are directly affecting glucose metabolism or simply increasing known risk factors for diabetes. OBJECTIVE: To study the 2 drugs most clearly implicated (clozapine and olanzapine) and risperidone using a frequently sampled intravenous glucose tolerance test. DESIGN: A cross-sectional design in stable, treated patients with schizophrenia evaluated using a frequently sampled intravenous glucose tolerance test and the Bergman minimal model analysis. SETTING: Subjects were recruited from an urban community mental health clinic and were studied at a general clinical research center.Patients Fifty subjects signed informed consent and 41 underwent the frequently sampled intravenous glucose tolerance test. Thirty-six nonobese subjects with schizophrenia or schizoaffective disorder, matched by body mass index and treated with either clozapine, olanzapine, or risperidone, were included in the analysis. MAIN OUTCOME MEASURES: Fasting plasma glucose and fasting serum insulin levels, insulin sensitivity index, homeostasis model assessment of insulin resistance, and glucose effectiveness. RESULTS: The mean +/- SD duration of treatment with the identified atypical antipsychotic agent was 68.3 +/- 28.9 months (clozapine), 29.5 +/- 17.5 months (olanzapine), and 40.9 +/- 33.7 (risperidone). Fasting serum insulin concentrations differed among groups (F(33) = 3.35; P = .047) (clozapine>olanzapine>risperidone) with significant differences between clozapine and risperidone (t(33) = 2.32; P = .03) and olanzapine and risperidone (t(33) = 2.15; P = .04). There was a significant difference in insulin sensitivity index among groups (F(33) = 10.66; P<.001) (clozapineolanzapine>risperidone) (clozapine vs risperidone, t(33) = 2.94; P = .006; olanzapine vs risperidone, t(33) = 2.42; P = .02). There was a significant difference among groups in glucose effectiveness (F(30) = 4.18; P = .02) (clozapine相似文献   

Effects of risperidone and olanzapine on remnant-like lipoprotein particle cholesterol (RLP-C) in schizophrenic patients

Second generation antipsychotics are associated with the risk of metabolic disorders such as diabetes mellitus and hyperlipidemia. Remnant-like lipoprotein particles cholesterol (RLP-C) are a known risk factor for cardiovascular events. The present study was performed to determine possible differences in fasting blood RLP-C levels between schizophrenic patients treated with risperidone as compared to olanzapine. Patients on olanzapine had significantly higher RLP-C levels than those on risperidone (p < 0.01). In olanzapine-treated patients there was no abnormality in fasting blood glucose levels, but fasting insulin levels and homeostasis model assessment of insulin resistance (HOMA-IR) were elevated. RLP-C levels were significantly correlated with plasma triglyceride concentrations in both the olanzapine- (p < 0.01) and risperidone-treated patients (p < 0.01). The regression line slope was greater for the olanzapine group, suggesting a greater influence of olanzapine on RLP-C. There was a significant correlation between RLP-C and HOMA-IR in the risperidone group (p < 0.01) but not in the olanzapine group (p = 0.80). These results suggest that blood glucose monitoring may not be sufficient to detect metabolic disorder and that measurement of RLP-C might be helpful for the screening for metabolic disorders associated with olanzapine therapy.     

Metformin as an adjunctive treatment to control body weight and metabolic dysfunction during olanzapine administration: a multicentric, double-blind, placebo-controlled trial

BACKGROUND: Excessive body weight gain (BWG) is a clinically relevant side effect of olanzapine administration. The primary objective of this study was to assess whether metformin prevents or reverses BWG in patients with schizophrenia or bipolar disorder under olanzapine administration. Secondarily we evaluated diverse metabolic variables. METHODS: Eighty patients taking olanzapine (5-20 mg daily for more than 4 consecutive months) were randomly allocated to metformin (n=40; 850 to 2550 mg daily) or placebo (n=40) group in a 12-week double-blind protocol. Waist circumference (WC) body weight (BW), body mass index (BMI) fasting glucose, glycated hemoglobin (Hb1c), insulin, an insulin resistance index (HOMA-IR) lipids, leptin, c-reactive protein, fibrinogen, cortisol and the growth hormone (GH) were evaluated at baseline and at week 12 of treatment. RESULTS: The metformin group lost 1.4+/-3.2 kg (p=0.01) and tended to decrease its leptin levels, whereas the placebo group maintained a stable weight: -0.18+/-2.8 kg (p=0.7). The HOMA-IR significantly increased after placebo (p=0.006) and did not change after metformin (p=0.8). No ostensible differences were observed in the other variables, even though metformin did not improve the lipid profile and the Hb1c levels. CONCLUSIONS: Metformin may safely assist olanzapine-treated patients in body weight and carbohydrate metabolism control.     

Metformin for prevention of weight gain and insulin resistance with olanzapine: a double-blind placebo-controlled trial.

OBJECTIVE: To assess whether metformin prevents body weight gain (BWG) and metabolic dysfunction in patients with schizophrenia who are treated with olanzapine. METHOD: Forty patients taking olanzapine (10 mg daily) were randomly allocated to a metformin (n = 20; 850 to 1700 mg daily) or placebo (n = 20) group in a 14-week double-blind study. Waist circumference (WC), BWG, body mass index (BMI) fasting glucose, insulin, and lipids were evaluated at baseline and at Weeks 7 and 14 of treatment. RESULTS: At Week 14, BWG (kg) was similar in the metformin group (5.5 kg) and the placebo group (6.3 kg), P = 0.4. There were no differences between the changes in BMI, WC, glucose, insulin, insulin resistance index (HOMA-IR), and plasma lipid levels observed in the treatment group and the placebo group; however, glucose levels decreased significantly after metformin administration (P = 0.02). The HOMA-IR decreased significantly in both groups, but 3 subjects from the placebo group developed fasting glucose levels greater than 5 mmol/L. After taking metformin, triglyceride levels increased, but the cholesterol profile improved significantly. CONCLUSIONS: Metformin did not prevent olanzapine-induced BWG. While some lipid parameters worsened during placebo, the HOMA-IR improved in both the placebo and the metformin groups. Carbohydrate metabolism impairment was not systematically observed during short-term olanzapine administration.     

A double‐blind,placebo‐controlled trial of rosiglitazone for clozapine‐induced glucose metabolism impairment in patients with Schizophrenia

Objective: The primary purpose of this 8‐week double‐blind, placebo‐controlled trial of rosiglitazone 4 mg/day was to examine its effect on insulin sensitivity index (SI) and glucose utilization (SG) in clozapine‐treated subjects with schizophrenia with insulin resistance. Method: Eighteen subjects were randomized and accessed with a Frequently Sampled Intravenous Glucose Tolerance Test (FSIVGTT) at baseline and at week 8 to estimate SG and SI. Results: Controlling for the baseline, comparing the rosiglitazone group with placebo group, there was a non‐significant improvement in SG (0.016 ± 0.006–0.018 ± 0.008, effect size = 0.23, P = 0.05) with a trend of improvement in SI in the rosiglitazone group (4.6 ± 2.8–7.8 ± 6.7, effect size = 0.18, P = 0.08). There was a significant reduction in small low‐density lipoprotein cholesterol (LDL‐C) particle number (987 ± 443–694 ± 415, effect size = 0.30, P = 0.04). Conclusion: Rosiglitazone may have a role in addressing insulin resistance and lipid abnormalities associated with clozapine.     

Ethnic heterogeneity in glucoregulatory function during treatment with atypical antipsychotics in patients with schizophrenia

OBJECTIVE: Atypical antipsychotics induce weight gain and are linked to increased diabetes risk, but their relative impact on factors that elevate disease risk are unknown. METHODS: We performed a 6-month, randomized, double-blind study to evaluate the effects of risperidone and olanzapine in patients with schizophrenia. At baseline and weeks 6 and 24, we quantified: (1) total adiposity by DEXA, (2) visceral adiposity by abdominal CT, and (3) insulin sensitivity (S(I)) and (4) pancreatic function ("disposition index", DI) by intravenous glucose tolerance test. RESULTS: At baseline, groups (risperidone: n=28; olanzapine: n=31) were overweight or obese by body mass index (risperidone: 28.4+/-5.4, olanzapine: 30.6+/-7.0kg/m(2)). Both drugs induced weight gain (p<0.004). Total adiposity was increased by olanzapine at 6 weeks (p=0.0006) and by both treatments at 24 weeks (p<0.003). Visceral adiposity was increased by olanzapine and risperidone by 24 weeks (p<0.003). S(I) did not deteriorate appreciably, although a downward trend was observed with risperidone. Given known ethnic differences in adiposity and S(I), we performed secondary analysis in African American and Hispanic subjects. In this subset, olanzapine expanded both total and visceral adiposity (p<0.02); no increase was observed with risperidone. There were modest downward trends for S(I) with both treatments. By week 24, olanzapine-treated subjects exhibited diminished DI (p=0.033), indicating inadequate pancreatic compensation for insulin resistance. CONCLUSIONS: This is the first prospective study in psychiatric patients that quantified antipsychotic effects on the multiple metabolic processes that increase diabetes risk. Results indicate that ethnic minorities may have greater susceptibility to antipsychotic-induced glucoregulatory complications.     

Effective resolution with olanzapine of acute presentation of behavioral agitation and positive psychotic symptoms in schizophrenia

Behavioral agitation and prominent positive psychotic symptoms often characterize the acute presentation of schizophrenia. The clinical treatment goal is a rapid control of these symptoms. The relative efficacy of olanzapine, a novel antipsychotic drug, was compared with that of the conventional antipsychotic drug haloperidol. A post hoc analysis conducted on a large multicenter, double-blind, 6-week study of acute-phase patients with DSM-III-R schizophrenia or schizophreniform or schizoaffective disorders treated with olanzapine (5-20 mg/day) or haloperidol (5-20 mg/day) assessed the treatment effects on agitation (Brief Psychiatric Rating Scale [BPRS] agitation score) and positive symptoms (BPRS positive symptom score). Overall, olanzapine-treated patients experienced significantly greater improvement in behavioral agitation than did haloperidol-treated patients (last observation carried forward [LOCF]; p < .0002). Both groups showed similar reductions in agitation scores during the first 3 weeks of therapy; olanzapine was associated with significantly greater improvements at weeks 4, 5, and 6 (observed cases [OC]). Similarly, patients with predominantly positive psychotic symptoms experienced significantly greater improvement in BPRS positive symptom scores with olanzapine compared with haloperidol (LOCF; p = .013). In olanzapine-treated patients, improvement in BPRS agitation and positive symptom scores was significantly greater at weeks 4, 5, and 6 (agitation scores, p < or = .01; positive symptom scores, p < .05) (OC). These data suggest that olanzapine may be considered a first-line treatment for the patient in an acute episode of schizophrenia.     

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.     

非经典抗精神病药对代谢的影响

目的：探讨非经典抗精神病药对精神分裂症患者血糖、糖化血红蛋白（HbA1C）、三酰甘油（TG）、高密度脂蛋白（HDL）和体质量的影响。方法：将176例精神分裂症患者分成氯氮平组（30例）、奥氮平组（30例）、奎硫平组（30例）、利培酮组（30例）、阿立哌唑组（30例）和齐拉西酮组（26例）,治疗6周。于治疗前和治疗6周测量空腹血糖、HbA1C、TG、HDL和体质量。结果：治疗前后血糖、HbA1C、TG、HDL和体质量在阿立哌唑组和齐拉西酮组无显著变化,氯氮平组和奥氮平组治疗后显著增高（P〈0.05或P〈0.01）;奎硫平组和利培酮组可引起体质量显著增加（P〈0.01）,但对血糖、HbA1C、TG、HDL影响不大。结论：阿立哌唑、齐拉西酮对精神分裂症患者代谢的影响较小,奎硫平、利培酮次之,氯氮平、奥氮平对患者代谢的影响最大。     

第二代抗精神病药对大鼠血糖、胰岛素和C肽分泌的影响

目的 了解第二代抗精神病药(氯氨平、奥氮平、喹硫平、阿立哌唑)对大鼠体重、空腹血糖、胰岛素和C肽分泌的影响.方法 25只雌性SD(Sprague Dawley,SD)大鼠随机均分成5组.分别给予氯氮平20 mg/(kg·d)、奥氮平5 mg/(kg·d)、喹硫平20 mg/(kg·d)、阿立哌唑5mg/(kg·d)和生理盐水灌胃,共28 d.在第1、7、14、28天分别剪尾采血,测体重及空腹血糖,于第28天测定空腹血浆胰岛素和C肽水平.结果 适应性喂养1周后,5组大鼠的空腹血糖和体重水平差异无统计学意义(P＞0.05).持续灌胃第14及28天,氯氮平、奥氮平和喹硫平组空腹血糖高于空白时照组(P＜0.05);持续灌胃28 d,氯氮平、奥氮平组的体重高于空白对照组(P＜0.05);与未加处理因素前(第1天)相比,氯氮平、奥氮平和喹硫平组体重和空腹血糖随时间的延长而增加(P＜0.05),而阿立哌哇组的变化无统计学意义(P＞0.05).持续灌胃第28天,氯氮平、奥氮平和喹硫平组空腹血浆胰岛素和C肽水平高于空白对照组(P＜0.05);而阿立哌唑组变化不明显(P＞0.05).结论 氯氮平、奥氮平、喹硫平可引起大鼠胰岛素抵抗和血糖代谢异常.     

Comparison of quetiapine and risperidone in the treatment of schizophrenia: A randomized, double-blind, flexible-dose, 8-week study

OBJECTIVE: To compare the efficacy and tolerability of quetiapine and risperidone in the treatment of schizophrenia. METHOD: In this 8-week, double-blind, multicenter, flexible-dose study, patients with schizophrenia (DSM-IV diagnosis) were randomly assigned to quetiapine (200-800 mg/day) or risperidone (2-8 mg/day). The primary hypothesis was that quetiapine was not inferior to risperidone. The primary efficacy measure was change from baseline in Positive and Negative Syndrome Scale (PANSS) total scores; secondary outcomes included response rate (> or = 40% reduction in PANSS scores), Clinical Global Impression-Change (CGI-C), and cognitive and social functioning. Tolerability assessments included treatment-emergent adverse events and changes in weight, glucose, and prolactin. Patients were recruited from June 2001 to September 2002. RESULTS: Patients (N = 673) were randomly assigned to quetiapine (N = 338, mean dose = 525 mg/day) or risperidone (N = 335, mean dose = 5.2 mg/day). The primary analysis demonstrated noninferiority between treatments (p < .05). Improvements with both treatments were comparable on PANSS total, negative, and general psychopathology subscales. Risperidone-treated patients had a significantly (p = .03) greater improvement in PANSS positive subscale score among all patients, but not among completers. Improvements in PANSS response rates, CGI-C, and cognitive function were similar between treatment groups. Changes in serum glucose and weight were minimal and comparable. The rate of extrapyramidal symptom (EPS)-related adverse events was significantly higher with risperidone (22%) than quetiapine (13%; p < .01). Somnolence was more common with quetiapine (26%) than risperidone (20%; p = .04). Prolactin levels increased with risperidone (+35.5 ng/mL), but decreased with quetiapine (-11.5 ng/mL; p < .001). CONCLUSIONS: Quetiapine and risperidone had broadly comparable clinical efficacy. Both agents improved cognitive and social functioning, and neither had a clinically significant effect on weight or glucose. Somnolence was more common with quetiapine; EPS and elevated prolactin rates were significantly higher with risperidone.     

Sexual dysfunction associated with second-generation antipsychotics in outpatients with schizophrenia or schizoaffective disorder: an empirical evaluation of olanzapine, risperidone, and quetiapine

OBJECTIVE: Evaluate sexual dysfunction, as measured by the Arizona Sexual Experience Scale (ASEX), in olanzapine-, quetiapine-, and risperidone-treated outpatients with schizophrenia or schizoaffective disorder. METHOD: The sexual functioning of 238 outpatients (age> or =18 years) with diagnoses of schizophrenia or schizoaffective disorder who took quetiapine (n=57), olanzapine (n=94), or risperidone (n=87) was evaluated with a one-time rating of the ASEX. The dose range for each treatment group was 5 to 40 mg/day (M=16.6 mg/day, SD=7.4) for olanzapine; 1 to 8 mg/day (M=3.9 mg/day, SD=1.6) for risperidone; and 50 to 900 mg/day (M=376.8 mg/day, SD=213.4) for quetiapine. Antipsychotic group designation was based on medication treatment at study entry (i.e., non-random assignment). Participant characteristics were collected to test for treatment group differences and for potential associations with severity of sexual dysfunction. The primary data analysis was a mixed linear model analysis of covariance with age, gender, and presence/absence of antidepressant known to cause sexual dysfunction included as covariates. RESULTS: There was a significant treatment effect on severity of sexual dysfunction, as measured by ASEX total scores (p=.04). The adjusted average ASEX total scores were lower in the quetiapine (M=17.80) than in the risperidone (M=19.69) or olanzapine (M=20.34) groups. Individual comparisons of the treatments on adjusted average ASEX total scores indicated a significant difference between olanzapine and quetiapine (p=.04), but no difference between risperidone and quetiapine (p=.17) or olanzapine and risperidone (p=.76). CONCLUSIONS: Quetiapine was associated with less severe sexual dysfunction than olanzapine and risperidone (albeit the effect between risperidone and quetiapine was not statistically significant). Olanzapine and risperidone were associated with a comparable degree of sexual dysfunction. Patients in all three treatment groups, nonetheless, experienced a moderately high degree of sexual dysfunction. Because the patients were not randomized, conclusions must be interpreted within the context of the quasi-experimental design.     

Novel antipsychotics: comparison of weight gain liabilities.

BACKGROUND: We performed a retrospective analysis of 122 clinical records of 92 male patients with DSM-III-R schizophrenia to examine the relative weight gain liabilities of clozapine, risperidone, olanzapine, and sertindole compared with haloperidol. We hypothesized that the unique pharmacodynamic profiles of these agents would contribute to different amounts and patterns of weight gain. METHOD: Data were analyzed to determine differences in weight gain during treatment among patients receiving 5 different drug treatments (clozapine [N = 20], olanzapine [N = 13], risperidone [N = 38], haloperidol [N = 43], and sertindole [N = 8]). Measures of maximal weight gain, final weight, and duration to maximal weight gain were calculated. RESULTS: Repeated measures analyses of variance controlling for age, treatment duration, and initial weight revealed statistically significant differences between groups on all 3 measures. Clozapine and olanzapine had the greatest maximal weight gain liability (F = 4.13, df = 4,23; p = .01). Weight gain with clozapine, but not olanzapine or risperidone, appears to persist (as reflected by final weight) despite behavioral interventions (e.g., nutritional consultation, suggested exercise regimen; F = 5.69, df = 4,23; p = .003). Clozapine- and olanzapine-treated subjects appeared to gain weight over a prolonged period of time, whereas risperidone-and sertindole-treated subjects had a more limited period of weight gain (F = 2.95, df = 4,25; p = .04). CONCLUSION: Clozapine and olanzapine caused the most weight gain, risperidone was intermediate, and sertindole had less associated weight gain than haloperidol. The relative receptor affinities of the novel antipsychotics for histamine H1 appear to be the most robust correlate of these clinical findings.     

Metformin for metabolic dysregulation in schizophrenic patients treated with olanzapine

The second generation antipsychotic drugs, such as risperidone, olanzapine, and quetiapine, are effective in treating patients with schizophrenia and have been considered as the first line therapy. Recently, increasing attention has been drawn to the potential diabetogenic effect of these novel antipsychotics. The goal of this study was to evaluate the effect of metformin treatment on the olanzapine-induced metabolic disturbance in schizophrenic patients. Twenty-four schizophrenic subjects who had received olanzapine treatment at least 3 months were assigned to the therapy with metformin 1500 mg/day for 8 weeks. The metabolic parameters were quantitatively assessed at baseline, weeks 2, 4, and 8 by using the intravenous glucose tolerance test. After an 8-week treatment with metformin, the body weight, fasting levels of glucose, triglyceride, and insulin, insulin secretion, and insulin resistance significantly decreased. Half of study subjects with metabolic syndrome obtained improvement after the metformin trial. Subjects' psychopathological condition remained unchanged during the study period. The olanzapine-induced metabolic disturbance could be reversed after 8-week metformin treatment. Based on the results of this study, we hypothesize that metformin could modulate the effect of olanzapine-induced metabolic disturbance.     

Male sexual dysfunction and quality of life in schizophrenia

OBJECTIVE: To describe the prevalence and clinical correlates of sexual dysfunction in a sample of adult male outpatients with schizophrenia treated with olanzapine, risperidone, quetiapine, or haloperidol, focusing on associations between sexual dysfunction and patient-perceived quality of life. METHOD: Sexual dysfunction was assessed in 139 outpatients with DSM-IV schizophrenia who were receiving olanzapine, risperidone, quetiapine, or haloperidol, but no other medications associated with sexual side effects. Structured assessments were made of psychiatric symptoms, quality of life, and relationships. RESULTS: Sexual dysfunction occurred in 45.3% of patients. Patients with and without sexual dysfunction did not significantly differ with respect to severity of psychiatric symptoms. However, as compared with patients without sexual dysfunction, patients with sexual dysfunction reported significantly lower ratings on global quality of life (t = 2.4, df = 136, p = .02) and the level of enjoyment in their life (t = 2.5, df = 136, p = .01). Patients with sexual dysfunction were significantly less likely than those without sexual dysfunction to report having a romantic partner (17.5% vs. 43.4%; chi(2) = 10.7, df = 1, p = .001), though they were not significantly less likely to report difficulty making friends (27.0% vs. 32.9%; chi(2) = 0.57, df = 1, p = .45). Among patients with romantic partners, those with sexual dysfunction reported significantly poorer quality of their relationships (t = 2.3, df = 42, p = .02) and were less likely to talk to their partner about their illness (t = 2.0, df = 42, p = .047). CONCLUSIONS: Sexual dysfunction is common in men with schizophrenia who are treated with olanzapine, risperidone, quetiapine, or haloperidol and is associated with diminished quality of life, decreased occurrence of romantic relationships, and reduced intimacy when relationships are established. High prevalence and substantial interference with quality of life combine to make sexual dysfunction an important area for clinical assessment and appropriate intervention in the community management of schizophrenia.     

A clinical study of the association of antipsychotics with hyperlipidemia

Following a prior Kentucky clinical practice study on metabolic syndrome, serum glucose and lipid levels were used in a new sample to determine whether after correcting for confounding factors, olanzapine hyperlipidemia risk may be higher under naturalistic non-randomized treatment. Serum glucose, total cholesterol, HDL cholesterol and triglyceride levels were assessed in 360 patients with severe mental illnesses. The initial goal was to focus on olanzapine lipid profiles, but visual data inspection indicated that quetiapine needed attention as well. Patients were divided into 3 groups: 57 (16%) on olanzapine, 105 (29%) on quetiapine, and 198 (55%) on other antipsychotics (risperidone, ziprasidone, aripiprazole or typicals). HDL and glucose levels were not significantly different across the three antipsychotic groups. When compared with other antipsychotics, olanzapine patients had a borderline significantly higher mean total serum cholesterol level (178 vs. 192 mg/dl, p=0.06) and mean triglyceride level (172 vs. 202 mg/dl, p=0.06). These differences became significant (p=0.006 and 0.03) after correcting for confounders. Quetiapine appeared overprescribed in patients with metabolic syndrome complications. When compared with other antipsychotics, quetiapine patients had a significantly higher mean total serum cholesterol level (178 vs. 194 mg/dl, p=0.004) and mean triglyceride level (172 vs. 225 mg/dl, p<0.001). These differences were significant (p=0.02 and <0.001) after correcting for confounders. This study is consistent with emerging literature that suggests that some antipsychotics may have direct and immediate effects on lipid levels beyond obesity effects. The effect sizes of olanzapine and quetiapine on hyperlipidemia were about 0.40 in this naturalistic study.     

Obesity, and not obstructive sleep apnea, is responsible for metabolic abnormalities in a cohort with sleep-disordered breathing

OBJECTIVE: To assess the profile of metabolic abnormalities in subjects with obstructive sleep apnea (OSA). PATIENTS AND METHODS: In a case-control study conducted in two years, from April 2003 to March 2005, data obtained from polysomnography study, lipid profile, fasting blood sugar, serum insulin, insulin resistance, leptin and adiponectin levels, were compared between the various groups. Included in the study were OSA subjects from a sleep laboratory and matched controls from the community. Those with recent myocardial infarction, upper airway surgery, class III/IV heart failure, pregnancy, acromegaly, chronic renal failure, or who were on treatment for hyperthyroidism, on systemic steroid treatment, or on hormonal replacement therapy, were excluded from the study. RESULTS: Forty apneic obese subjects (AHI=32.19, range 13-52.75) were compared with 40 non-apneic obese controls (AHI=1.3, range 0-2.45) and 40 normal weight control subjects (AHI=0.7, range 0-1). No significant difference was noted in levels of fasting blood sugar, insulin resistance (obese apneics 61.9, obese controls 47.8, non-obese controls 19.1), leptin (obese apneics 10.65 microg/L, obese controls 8.52 microg/L, non-obese controls 2.83 microg/L) or adiponectin (obese apneics 4959.3 ng/ml, obese controls 5706 ng/ml, non-obese controls 7412 ng/ml) in the OSA group compared to obese controls. CONCLUSIONS: OSA has no independent association with lipid abnormalities, insulin resistance, serum leptin and adiponectin levels. In multivariate analysis, obesity was the major determinant of metabolic abnormalities in this cohort.     

Long-term olanzapine treatment: weight change and weight-related health factors in schizophrenia

BACKGROUND: Weight change and the weight-related health factors of nonfasting serum glucose, serum cholesterol, and diastolic blood pressure levels were analyzed in patients with DSM-III-R schizophrenia and related disorders who received treatment with olanzapine for up to 3 years, and comparisons were made to patients treated with haloperidol. Baseline body mass index (BBMI; kg/m2) and dose (mg/day) were investigated as predictors of long-term weight change experienced during olanzapine treatment. METHOD: This analysis retrospectively examined 573 patients receiving olanzapine and 103 patients receiving haloperidol for 39 weeks or more from a study of 1,996 patients randomly assigned 2:1 to either olanzapine, 5 to 20 mg/day, or haloperidol, 5 to 20 mg/day. After 6 weeks of acute therapy, patients continued for 1 year or more with either double-blind or open-label olanzapine therapy or double-blind haloperidol therapy. RESULTS: Mean weight gain for olanzapine-treated patients observed for a median of 2.54 years trended toward a plateau after the first 39 weeks of treatment with a last-observation-carried-forward mean weight change of 6.26 kg (13.8 lb) and a median of 5.90 kg (13.0 lb). This was significantly higher than that for haloperidol-treated patients, whose mean weight gain was 0.69 kg (1.5 lb) after 1.15 years (p < .001). Patients with higher BBMI (> 27.6) gained significantly less weight during treatment with olanzapine than their lighter counterparts (BBMI < 27.6) (p < .001). The effect of olanzapine dose on weight was not significant (p > or = . 183). Median serum glucose at endpoint was not significantly associated (p = .096) with weight change for olanzapine. Median serum cholesterol and diastolic blood pressure for olanzapine-treated patients at endpoint showed a relationship with weight change that was statistically (p < or = .001) but not clinically significant. The difference in incidence of elevated serum glucose, cholesterol, or diastolic blood pressure between olanzapine and haloperidol therapy groups was not different (p > .05). CONCLUSION: Mean weight gain during olanzapine treatment trended toward a plateau after the initial 39 weeks of treatment with no further significant gain out to 3 years. Higher BBMI was predictive of a lower long-term weight gain, while dose was not a significant predictor of greater longer term weight change. The relationship between weight change and glucose was not statistically significant. The association between weight change and changes in cholesterol as well as changes in diastolic blood pressure was statistically significant but not considered clinically relevant based on the ranges observed.