Weight gain induced by clozapine

A systematic review and meta-analysis of the association between clozapine and norclozapine serum levels and peripheral adverse drug reactions

RATIONALE

Clozapine is the most effective antipsychotic for treatment-refractory schizophrenia for reducing positive psychotic symptoms. It is associated with a reduction in hospitalisation and overall mortality. In spite of this, clozapine remains underutilised due to its complex adverse drug reaction (ADR) profile.

OBJECTIVE

This systematic review aims to investigate the association of clozapine and norclozapine serum levels, and peripheral ADRs.

METHODS

Studies were searched from four electronic databases (PubMed, EMBASE, PsycINFO and CINAHL) from inception to 12 June 2020. Studies were included if they had adult patients, provided data on steady-state trough clozapine or norclozapine levels and reported on clozapine-associated ADRs. Pregnant women, case reports and series were excluded.

RESULTS

A statistically significant correlation was found for clozapine serum levels and triglycerides (n = 70; r = 0.303, 95% CI 0.0119-0.546, p = 0.042), heart rate (n = 137; r = 0.269, 95% CI 0.0918-0.486, p = 0.035), and overall combined ADRs (n = 160; r = 0.264, 95% CI 0.110-0.405, p = 0.001), but not for absolute neutrophil count (n = 223; r = - 0.164, 95% CI - 0.529-0.253, p = 0.444) or total white cell count (n = 18; r = 0.0176, 95% CI - 0.203-0.237, p = 0.878). Interestingly, norclozapine serum levels were found to be statistically correlated to triglycerides (n = 120; r = 0.211, 95% CI 0.0305-0.378, p = 0.022), total cholesterol (n = 120; r = 0.272, 95% CI 0.0948-0.432, p = 0.003) and weight gain (n = 118; r = 0.208, 95% CI 0.0261-0.377, p = 0.025).

CONCLUSIONS

Heart rate, triglycerides and combined ADRs are significantly correlated with clozapine levels, and triglycerides, total cholesterol and weight gain with norclozapine levels. Future prospective, randomised controlled studies are needed to identify the cause-effect relationship between clozapine levels and peripheral ADRs.

The Role of Proopiomelanocortin and α-Melanocyte-Stimulating Hormone in the Metabolic Syndrome in Psychiatric Disorders: A Narrative Mini-Review

The metabolic syndrome (MetS) comprises abdominal obesity, preclinical or full diabetes type 2, arterial hypertension, and dyslipidemia and affects a significant proportion of the general population with a remarkably higher prevalence in patients suffering from psychiatric disorders. However, studies exploring the pathogenetic link between MetS and psychiatric diseases are rare. Here, we aim to narrow this gap in knowledge by providing a narrative review on this topic that focuses on two psychiatric diseases, namely on schizophrenia and posttraumatic stress disorder (PTSD) since we assume them to be associated with two different main causalities of MetS: in schizophrenia, MetS evidently develops or aggravates in response to antipsychotic drug treatment while it assumingly develops in response to stress-induced endocrine and/or epigenetic alterations in PTSD. First, we compared the prevalences of MetS and associated pathologies (which we took from the latest meta-analyses) among different psychiatric disorders and were surprised that the prevalences of arterial hypertension and hyperglycemia in PTSD almost doubles those of the other psychiatric disorders. Next, we performed a literature search on the neurobiology of MetS and found numerous articles describing a role for proopiomelanocortin (POMC) in MetS. Thus, we concentrated further analysis on POMC and one of its downstream effector hormones, α-melanocyte-stimulating hormone (α-MSH). We found some evidence for a role of POMC in both PTSD and schizophrenia, in particular in antipsychotic-induced MetS, as well as for α-MSH in schizophrenia, but, surprisingly, no study on α-MSH in PTSD. Taken together, our synopsis reveals, first, a potential interaction between the POMC system and stress in the assumingly at least partially shared pathogenesis of psychiatric disorders and MetS, second, that modulation of the POMC system, in particular of the melanocortin 3 and 4 receptors, might be a promising target for the treatment of MetS and, third, that the DNA methylation status of POMC might speculatively be a promising biomarker for MetS in general and, possibly, in particular in the context of stress-related psychiatric conditions such as PTSD. To best of our knowledge, this is the first review on the role of the POMC system in MetS in psychiatric disorders.

The Complex Relationship between Antipsychotic-Induced Weight Gain and Therapeutic Benefits: A Systematic Review and Implications for Treatment

Background: Antipsychotic-induced weight gain (AIWG) and other adverse metabolic effects represent serious side effects faced by many patients with psychosis that can lead to numerous comorbidities and which reduce the lifespan. While the pathophysiology of AIWG remains poorly understood, numerous studies have reported a positive association between AIWG and the therapeutic benefit of antipsychotic medications.

Objectives: To review the literature to (1) determine if AIWG is consistently associated with therapeutic benefit and (2) investigate which variables may mediate such an association.

Data Sources: MEDLINE, Google Scholar, Cochrane Database and PsycINFO databases were searched for articles containing all the following exploded MESH terms: schizophrenia [AND] antipsychotic agents/neuroleptics [AND] (weight gain [OR] lipids [OR] insulin [OR] leptin) [AND] treatment outcome. Results were limited to full-text, English journal articles.

Results: Our literature search uncovered 31 independent studies which investigated an AIWG-therapeutic benefit association with a total of 6063 enrolled individuals diagnosed with schizophrenia or another serious mental illness receiving antipsychotic medications. Twenty-two studies found a positive association while, 10 studies found no association and one study reported a negative association. Study variables including medication compliance, sex, ethnicity, or prior antipsychotic exposure did not appear to consistently affect the AIWG-therapeutic benefit relationship. In contrast, there was some evidence that controlling for baseline BMI/psychopathology, duration of treatment and specific agent studied [i.e., olanzapine (OLZ) or clozapine (CLZ)] strengthened the relationship between AIWG and therapeutic benefit.

Limitations: There were limitations of the reviewed studies in that many had small sample sizes, and/or were retrospective. The heterogeneity of the studies also made comparisons difficult and publication bias was not controlled for.

Conclusions: An AIWG-therapeutic benefit association may exist and is most likely to be observed in OLZ and CLZ-treated patients. The clinical meaningfulness of this association remains unclear and weight gain and other metabolic comorbidities should be identified and treated to the same targets as the general population. Further research should continue to explore the links between therapeutic benefit and metabolic health with emphasis on both pre-clinical work and well-designed prospective clinical trials examining metabolic parameters associated, but also occurring independently to AIWG.

Associations among obesity, acute weight gain, and response to treatment with olanzapine in adolescent schizophrenia

OBJECTIVE

The purpose of this study was to investigate associations between body weight and illness characteristics, including weight gain and therapeutic efficacy, in adolescents with schizophrenia.

METHODS

Adolescents ages 13-17 years (n = 107) with American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) schizophrenia enrolled in a 6 week, double-blind, placebo-controlled trial comparing olanzapine and placebo. Therapeutic response was assessed by the Brief Psychiatric Rating Scale for Children (BPRS-C). Secondary outcomes included the Clinical Global Impressions-Severity (CGI-S) scale and Positive and Negative Syndrome Scale (PANSS). Obesity was defined as sex-/age-adjusted body mass index (BMI) ≥ 95th percentile. Linear regression was used to analyze the relationship between weight gain and psychiatric symptom improvement; logistic regression was conducted to identify predictors of baseline obesity.

RESULTS

Weight gain was significantly correlated with greater BPRS-C reduction among olanzapine-treated subjects (r = -0.31, p<0.01), whereas a trend was observed among placebo-treated subjects (r = -0.31, p = 0.08). However, this relationship became nonsignificant when analyses were controlled for duration of olanzapine treatment (p=0.12), and a treatment by weight gain interaction did not emerge in a repeated-measures mixed model analysis that included time in the study (t = 1.27, p = 0.21). Additionally, weight gain ≥ 7% was not significantly associated with response or remission. Among 17 adolescents (16%) with obesity at study entry, obesity was not significantly associated with endpoint BPRS-C illness severity. However, girls (p = 0.03), individuals hospitalized within the past year (p = 0.02), and those with less severe overall (p = 0.03) and negative symptoms (p = 0.003) according to the CGI-S and PANSS negative subscale, respectively, were more likely to be obese at baseline.

CONCLUSION

Baseline obesity was associated with lower illness severity, which could be mediated by greater treatment adherence, leading to more weight gain. Olanzapine-related weight gain was not independently associated with symptomatic outcome when controlling for treatment duration. Additional studies are needed to extend these findings to other disorders and medications.

Metabolic syndrome in schizophrenia: Differences between antipsychotic-naïve and treated patients

Metabolic syndrome (MetS) has been recognized as a risk factor for cardiovascular morbidity and mortality in general population and in patients with severe mental illnesses like schizophrenia. This paper reviews studies on MetS in schizophrenia and related psychotic disorders, and assesses the contribution of antipsychotics toward the development of MetS. Databases of Medline (PubMed), PsycINFO, and Scopus were searched for MetS, psychotic disorders, and antipsychotic drugs from inception till present. Prevalence of MetS in patients with schizophrenia was found to be ranging from 3.3% to 68.0%. Prevalence in antipsychotic-naïve and antipsychotic-treated patients ranged between 3.3-26.0% and 32.0-68.0% respectively, and was higher in younger patients, female gender and Hispanics, and lower in African-Americans and Orientals. Prevalence of metabolic abnormalities was higher in patients receiving second generation antipsychotics (SGAs), especially with clozapine, olanzapine, and risperidone, as compared to first generation antipsychotics (FGAs). Antipsychotic-induced changes on metabolic indices became evident after 2 weeks and reached maximum at 3 months of treatment. There is a need to sensitize the mental health professionals at all levels about the need of screening and monitoring for MetS in patients receiving antipsychotics.

Management of antipsychotic-related weight gain

Despite variations across individuals and agents, antipsychotics are associated with clearly documented weight gain and adverse metabolic effects. Although increased appetite/caloric intake and various receptors, hormones and peptides have been implicated, biological mechanisms contributing to the increase in weight and glucose and lipid abnormalities with antipsychotics are largely unknown. This has hampered the creation of antipsychotics that are free of cardiometabolic effects, even in antipsychotic-naive/early-phase patients, as well as the development of strategies that can prevent or drastically diminish the adverse cardiometabolic effects. In general, three strategies can reduce the cardiometabolic risk of antipsychotics: switching to a less orexigenic/metabolically adverse antipsychotic; adjunctive behavioral treatments; and adjunctive pharmacologic interventions. However, each of these strategies has only been shown to be modestly effective. Among different behavioral interventions (N = 14, n = 746), group and individual treatment, dietary counseling and cognitive-behavioral therapy seem to be similarly effective. Among 15 different pharmacologic strategies (N = 35, n = 1629), only metformin, fenfluramine, sibutramine, topiramate and reboxetine were more effective than placebo, with the most evidence being available for metformin, and no head-to-head trials comparing individual pharmacologic interventions. However, even in the most successful trials the risk reduction was modest. Weight was not decreased to a pretreatment level, and despite superiority compared with placebo, weight gain still often occurred, particularly in antipsychotic-naive patients and when interventions were 'preventively' coinitiated with antipsychotics. Future research should focus on combining treatment modalities or agents and on exploring novel mechanism-based interventions.

Antipsychotic-induced body weight gain: predictors and a systematic categorization of the long-term weight course

OBJECTIVE

To explore the impact of premorbid and baseline body mass indices (BMIs) as well as BMI of patient's parents and associated variables on the prediction of antipsychotic-induced body weight gain.

METHODS

Retrospective/cross-sectional data of 65 patients receiving clozapine, olanzapine and/or risperidone were assessed according to a systematic categorization of the long-term (7.3+/-9.2 years) weight course and evaluated using descriptive, explorative correlation and regression analyses.

RESULTS

Increased values of parents' BMI (p=0.041) and patients' BMI at premorbid stage (p=0.039) and prior to first antipsychotic treatment (p=0.032) as well as female gender (p=0.012), younger age (p=0.005) and non-smoking (p=0.047) have the most predictive value on body weight gain under antipsychotic treatment including pre-treatment with typical antipsychotics. Weight gain under atypical antipsychotics (pre-treatment excluded) is predicted by an increased premorbid BMI (p=0.019). Conversely, a low BMI prior to first antipsychotic treatment predicts a higher acceleration of BMI change (p=0.008) in vulnerable individuals, but not total BMI change itself. Furthermore, a diagnosis of a schizophrenia spectrum disorder showed a trend towards the prediction of an increased atypical DeltaBMI (p=0.067), possibly due to a longer treatment duration with atypical antipsychotics (p<0.001).

DISCUSSION

The study indicates increased parents' BMI and patients' premorbid BMI, female gender, younger age and - as a trend - the diagnosis of a schizophrenia spectrum disorder to be predictors for antipsychotic-induced body weight gain involving atypical antipsychotics. Data contribute to the assumption of a strong impact of predispositional factors on weight gain, besides treatment-related factors.

Clozapine versus typical neuroleptic medication for schizophrenia

BACKGROUND

Long-term drug treatment of schizophrenia with typical antipsychotics has limitations: 25 to 33% of patients have illnesses that are treatment-resistant. Clozapine is an antipsychotic drug, which is claimed to have superior efficacy and to cause fewer motor adverse effects than typical drugs for people with treatment-resistant illnesses. Clozapine carries a significant risk of serious blood disorders, which necessitates mandatory weekly blood monitoring at least during the first months of treatment.

OBJECTIVES

To evaluate the effects of clozapine compared with typical antipsychotic drugs in people with schizophrenia.

SEARCH STRATEGY

For the current update of this review (March 2006) we searched the Cochrane Schizophrenia Group Trials Register.

SELECTION CRITERIA

All relevant randomised clinical trials (RCTs).

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data we calculated relative risks (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis, based on a fixed-effect model. We calculated numbers needed to treat/harm (NNT/NNH) where appropriate. For continuous data, we calculated weighted mean differences (WMD) again based on a fixed-effect model.

MAIN RESULTS

We have included 42 trials (3950 participants) in this review. Twenty-eight of the included studies are less than 13 weeks in duration, and, overall, trials were at significant risk of bias. We found no significant difference in the effects of clozapine and typical neuroleptic drugs for broad outcomes such as mortality, ability to work or suitability for discharge at the end of the study. Clinical improvements were seen more frequently in those taking clozapine (n=1119, 14 RCTs, RR 0.72 CI 0.7 to 0.8, NNT 6 CI 5 to 8). Also, participants given clozapine had fewer relapses than those on typical antipsychotic drugs (n=1303, RR 0.62 CI 0.5 to 0.8, NNT 21 CI 15 to 49). BPRS scores showed a greater reduction of symptoms in clozapine-treated patients, (n=1145, 16 RCTs, WMD -4.22 CI -5.4 to -3.1), although the data were heterogeneous (Chi(2) 0.0001, I(2) 66%). Short-term data from the SANS negative symptom scores favoured clozapine (n=196, 5 RCTs, WMD -5.92 CI -7.8 to -4.1). We found clozapine to be more acceptable in long-term treatment than conventional antipsychotic drugs (n=982, 16 RCTs, RR 0.60 CI 0.5 to 0.7, NNT 15 CI 12 to 20). Blood problems occurred more frequently in participants receiving clozapine (3.2%) compared with those given typical antipsychotics (0%) (n=1031, 13 RCTs, RR 7.09 CI 2.0 to 25.6). Clozapine participants experienced more drowsiness, hypersalivation, or temperature increase, than those given conventional neuroleptics. However, clozapine patients experienced fewer motor adverse effects (n=1433, 18 RCTs, RR 0.58 CI 0.5 to 0.7, NNT 5 CI 4 to 6).The clinical effects of clozapine were more pronounced in participants resistant to typical neuroleptics in terms of clinical improvement (n=370, 4 RCTs, RR 0.71 CI 0.6 to 0.8, NNT 4 CI 3 to 6) and symptom reduction. Thirty-four per cent of treatment-resistant participants had a clinical improvement with clozapine treatment.

AUTHORS' CONCLUSIONS

Clozapine may be more effective in reducing symptoms of schizophrenia, producing clinically meaningful improvements and postponing relapse, than typical antipsychotic drugs - but data are weak and prone to bias. Participants were more satisfied with clozapine treatment than with typical neuroleptic treatment. The clinical effect of clozapine, however, is, at least in the short term, not reflected in measures of global functioning such as ability to leave the hospital and maintain an occupation. The short-term benefits of clozapine have to be weighed against the risk of adverse effects. Within the context of trials, the potentially dangerous white blood cell decline seems to be more frequent in children and adolescents and in the elderly than in young adults or people of middle-age.The existing trials have largely neglected to assess the views of participants and their families on clozapine. More community-based long-term randomised trials are needed to evaluate the efficacy of clozapine on global and social functioning as trials in special groups such as people with learning disabilities.

Eating and weight related cognitions in people with Schizophrenia : a case control study

Background

Patients with antipsychotic-induced weight gain (WG) regularly report on unsuccessful dietary trials, which suggests strong biological weight gain drive that is extremely hard to overcome with thoughts, such that behaviour doesn't change despite some intent to change. The purpose of the present study was to assess cognitions specifically related to restrained eating in severely overweight patients with schizophrenia treated with antipsychotic drugs.

Methods

Forty outpatients with schizophrenia and 40 controls without psychiatric disability were included. Both groups were composed of one subgroup severely overweight (defined as a BMI > 28), and a comparison sample (BMI<28). The revised version of the Mizes Anorectic cognitive questionnaire (MAC-R) was used in this cross-sectional case-control study.

Results

Gender was significantly related to eating disorders cognition, women scoring higher than men. Patients with schizophrenia in general scored higher on the MAC-R total scale and on the MAC-R subscale 2, the latter score representing rigid weight regulation and fear of weight gain. When comparing the two groups of subjects with BMI < 28, it appeared that patients with schizophrenia also scored higher on MAC-R total scale, the subscales 2 and 3, the latter subscale 3, indicating altered self control and self-esteem.

Conclusion

As is the case in weight gain of subjects without schizophrenia, the present results suggest that the cognitive distortions, as assessed by the MAC-R, may play an important role in weight gain also in patients with schizophrenia, and in weight gain associated with antipsychotic pharmacotherapy. Particular attention to these processes may help to improve the management of antipsychotic drugs induced weight gain.

[Antipsychotic drug-induced changes in metabolism]

Antipsychotic medications are a mainstay in the treatment of schizophrenia and are widely used in other psychiatric conditions. New generation antipsychotic agents (NGAs) are increasingly replacing first generation antipsychotic agents (FGAs), mainly due to a decreased risk for extrapyramidal symptoms, better overall tolerability, as well as some efficacy advantages. However, some of these NGAs are associated with adverse metabolic effects such as substantial weight gain, the induction of insulin resistance and lipid disorders. Among these substances, clozapine and olanzapine induce the most significant weight gain, olanzapine mainly by increasing body fat and both of these antipsychotics have been associated with disturbances in glucose metabolism. Diabetes mellitus induced by treatment with some NGAs occurred in many cases within days to weeks after initiation of SGA therapy, in some cases hyperglycemia promptly resolved after discontinuation of the medication and several reports have documented recurrent hyperglycemia after a rechallenge with the same drug. One possible pathomechanism for hyperglycemia induced by these NGAs is the induction of insulin resistance via humoral and/or cellular pathways. Alternatively, NGA induced diabetes may occur because of weight gain or a change in body fat distribution with a shift to a predominantly visceral fat type or through a direct effect on insulin sensitive target tissues. In this article we like to review the metabolic side effects of NGA treatment, highlight recent advances in the pathogenesis of these metabolic complications and discuss potential treatments of these side effects.

Long-term treatment with atypical antipsychotics and the risk of weight gain : a literature analysis

The aim of this review is to analyse and summarise the literature data about the incidence of weight gain in patients exposed to atypical antipsychotics during long-term (>or=1 year) treatment regimens. Despite the clinical relevance of the topic, the vast majority of reviewed studies showed methodological limitations. Some trials had retrospective analysis, and concomitant medications also associated with an increased risk of weight gain, such as antidepressants and mood stabilisers, were often prescribed. Results were obtained from clinical trials conducted using flexible dosages; thus, the relationship between dosage and weight change was not explored adequately. Also, in a large number of studies, the average antipsychotic daily dose was lower than the usual dosage in clinical practice. Moreover, weight gain was evaluated by different measures, such as mean weight gain in the enrolled population, percentage of patients who gained >7% of basal weight or body mass index (BMI) variations from baseline. In short-term studies, a definite rank order of weight-gain potential among atypical antipsychotics has been demonstrated: clozapine is related to the highest risk of weight gain, followed in decreasing order of magnitude by olanzapine, quetiapine, risperidone, amisulpride, aripiprazole and ziprasidone. However, in long-term studies, except for clozapine at one end of the scale and ziprasidone at the other, the differences in weight-gain liability showed by the other atypical antipsychotics became less intense. Differences between short-term and long-term treatment could be due to a complex overlapping of different factors, both drug-specific (relative receptorial affinity; timing of weight change plateau; and drug-specific/dose-dependent weight gain), and patient-specific (genetic vulnerability; sex; age; BMI; weight before starting antipsychotic treatment; type of psychiatric disorder; and individual lifestyle). There is an urgent need for well designed, randomised controlled trials to assess firmly both the differential effects of atypical antipsychotics on weight and the role of other factors in contributing to iatrogenic unwanted weight changes. Meanwhile, the well known benefits shown by some atypical antipsychotics in reducing akathisia and other extrapyramidal adverse effects and improving cognition should be carefully balanced with the problems of weight gain, other metabolic complications and higher health care costs.

Metabolic risk factor profile associated with use of second generation antipsychotics: a cross sectional study in a Community Mental Health Centre

BACKGROUND

Second generation antipsychotics (SGA) have demonstrated several advantages over first generation antipsychotics (FGA) in terms of positive, negative, cognitive, and affective symptoms and a lower propensity for extrapyramidal side effects. Despite these undeniable advantages, SGA have been associated with causing and exacerbating metabolic disorders, such as obesity, diabetes, and hyperlipidemia. This cross sectional study aimed to evaluate the metabolic risk factor profile associated with use of SGAs in comparison with non -treated control patients.

METHODS

The study was carried out at a Community Mental Health Centre (CMHC) in Bologna. The study subjects were outpatients with serious mental disorders treated with SGA (clozapine, olanzapine, risperidone, quetiapine). A sample of adult men and women suffering from idiopathic hyperhydrosis, without psychiatric history or antipsychotic treatment, were randomly selected from outpatients of the Department of Neurology in Bologna as a reference group. We investigated differences among the treatment and reference groups for glycaemia, cholesterolaemia and triglyceridaemia levels.

RESULTS

The study sample was composed of 76 patients, 38 males and 38 females. The reference group was composed of 36 subjects, 19 females and 17 males. All patients treated with SGAs had higher mean glycaemia and triglyceridaemia and a significantly higher risk of receiving a diagnosis of hyperglycaemia and hypertriglyceridaemia than the reference group. We did not find any differences in mean glycaemia or mean triglyceridaemia levels among treatment groups. Patients with clozapine had a significantly higher mean BMI value and rate of obesity than patients treated with other SGAs.

CONCLUSION

The rate of obesity and metabolic disorders observed in this study were higher than the prevalence in the control group and similar to that previously reported in psychiatric samples; these findings imply per se that more attention should be paid to the metabolic condition of psychiatric patients. In line with the International Consensus Conferences we recommend that monitoring of weight, fasting plasma glucose, cholesterol and triglyceride levels be obtained in routine clinical practice with all antipsychotics.

Acute weight gain, gender, and therapeutic response to antipsychotics in the treatment of patients with schizophrenia

BACKGROUND

Previous research indicated that women are more vulnerable than men to adverse psychological consequences of weight gain. Other research has suggested that weight gain experienced during antipsychotic therapy may also psychologically impact women more negatively. This study assessed the impact of acute treatment-emergent weight gain on clinical and functional outcomes of patients with schizophrenia by patient gender and antipsychotic treatment (olanzapine or haloperidol).

METHODS

Data were drawn from the acute phase (first 6-weeks) of a double-blind randomized clinical trial of olanzapine versus haloperidol in the treatment of 1296 men and 700 women with schizophrenia-spectrum disorders. The associations between weight change and change in core schizophrenia symptoms, depressive symptoms, and functional status were examined post-hoc for men and women and for each medication group. Core schizophrenia symptoms (positive and negative) were measured with the Brief Psychiatric Rating Scale (BPRS), depressive symptoms with the BPRS Anxiety/Depression Scale and the Montgomery-Asberg Depression Rating Scale, and functional status with the mental and physical component scores on the Medical Outcome Survey-Short Form 36. Statistical analysis included methods that controlled for treatment duration.

RESULTS

Weight gain during 6-week treatment with olanzapine and haloperidol was significantly associated with improvements in core schizophrenia symptoms, depressive symptoms, mental functioning, and physical functioning for men and women alike. The conditional probability of clinical response (20% reduction in core schizophrenia symptom), given a clinically significant weight gain (at least 7% of baseline weight), showed that about half of the patients who lost weight responded to treatment, whereas three-quarters of the patients who had a clinically significant weight gain responded to treatment. The positive associations between therapeutic response and weight gain were similar for the olanzapine and haloperidol treatment groups. Improved outcomes were, however, more pronounced for the olanzapine-treated patients, and more olanzapine-treated patients gained weight.

CONCLUSIONS

The findings of significant relationships between treatment-emergent weight gain and improvements in clinical and functional status at 6-weeks suggest that patients who have greater treatment-emergent weight gain are more likely to benefit from treatment with olanzapine or haloperidol regardless of gender.

Hyperglycemia with antipsychotic treatment

Diabetes and mental disorders are common chronic illnesses in the United States. Recently, the introduction of a new class of atypical antipsychotic medications has been a major treatment advance for patients with mental disorders. Because of increased use of atypical antipsychotic medications, new and unanticipated side effects have often appeared. Treatment-emergent diabetes has been described for conventional and atypical antipsychotics. People with schizophrenia may be at increased risk for type 2 diabetes because of the side effects of antipsychotic medication, underlying predisposition, and less healthy lifestyles.

Epidemiology, implications and mechanisms underlying drug-induced weight gain in psychiatric patients

Body weight gain frequently occurs during drug treatment of psychiatric disorders and is often accompanied by increased appetite or food craving. While occurrence and time course of this side effect are difficult to predict, it ultimately results in obesity and the morbidity associated therewith in a substantial part of patients, often causing them to discontinue treatment even if it is effective. This paper reviews the available epidemiological data on the frequency and extent of weight gain associated with antidepressant, mood-stabilizing, and antipsychotic treatment. Possible underlying pathomechanisms are discussed with special attention to central nervous control of appetite including the role of leptin and the tumor necrosis factor system. Metabolic alterations induced by drug treatment such as type 2 diabetes mellitus and the metabolic syndrome are also considered. Weight gain appears to be most prominent in patients treated with some of the second generation antipsychotic drugs and with some mood stabilizers. Marked weight gain also frequently occurs during treatment with most tricyclic antidepressants, while conventional antipsychotics typically induce only slight to moderate weight gain. Serotonin reuptake inhibitors may induce weight loss during the first few weeks, but some of them induce weight gain during long-term treatment. Several antidepressant and antipsychotic drugs are identified which reliably do not cause weight gain or even reduce weight. Based on these insights, countermeasures to manage drug-induced weight gain are suggested.

Trends in antipsychotic use in a Texas medicaid population of children and adolescents: 1996 to 2000

The purpose of this study was to examine the current trends in prescribing antipsychotics to children and adolescents within the Texas Medicaid Program. Total enrollments of children and adolescents, ranging from infants to 19-year-olds, in the Texas Medicaid Program were determined for each calendar year from 1996 to 2000. Prevalence was defined as the number of children and/or adolescents with at least one Medicaid prescription claim for an antipsychotic per 1,000 enrollees. Trends in prevalence were assessed over a 5-year period using annual descriptive analyses. In addition, total expenditures for antipsychotics were evaluated within this population. Over the 5-year period, an additional 12.25 children and adolescents per 1,000 enrollees (+160%) were prescribed antipsychotics. The prevalence of atypical antipsychotics increased by 13.29 per 1,000 enrollees (+494%) over the same period. In children and adolescents above 2 years of age, the prevalence of antipsychotic use increased in all groups. Antipsychotic usage was more common in children and adolescents between the ages of 10 and 14 years compared to other age groups. Male and female antipsychotic prevalence rates increased during the 5-year period. The increase in total expenditures was related to the increased utilization of atypical antipsychotics.

Gene expression profiling with DNA microarrays: advancing our understanding of psychiatric disorders

DNA microarray transcriptome profiling of the postmortem brain opens novel horizons in understanding molecular changes associated with complex psychiatric disorders. With careful analysis and interpretation of microarray data we are uncovering previously unknown, expression patterns that maybe subject-specific and pivotal in understanding the disease process. In our recent studies, analyses of the prefrontal cortex of subjects with schizophrenia and matched controls uncovered complex changes in the expression of genes related to presynaptic secretory release, GABAergic and glutamatergic transmission, metabolic pathways, myelination, as well as cAMP and phosphoinositol second messenger systems. Our goal will be to integrate this expression data within the context of the relevant anatomical, biochemical, molecular, imaging and clinical findings.

CYP2D6 polymorphisms and atypical antipsychotic weight gain

Reports have linked atypical antipsychotics (AAPs) with weight gain. The polymorphic CYP2D6 involved in metabolism has been associated with medication morbidity. Eleven subjects receiving olanzapine were genotyped for CYP2D6 to examine the relationship between 2D6 and AAP weight gain. Using a linear regression, the dependent variable was percent change in body mass index (BMI). Genotype, dose and duration of treatment were independent. Genotype was significant (P<0.0097) for those with a *1/*3 or *4 genotype experiencing a larger percent BMI change than those with a *1/*1 genotype. This may be due to increased olanzapine concentrations leading to increased exposure, which may trigger AAP weight gain.

Bodyweight gain associated with atypical antipsychotics: epidemiology and therapeutic implications

Atypical antipsychotic medications are associated with different adverse effects and efficacy profiles compared with conventional antipsychotics (i.e. less extrapyramidal symptoms, improved-efficacy against negative symptoms and cognitive deficits, and most often a greater ability to improve patients' quality of life). However, the atypical antipsychotics may be associated with clinically significant bodyweight gain, increasing the risk of medical comorbidity, including diabetes mellitus, hypertension, cardiovascular disease and hyperlipidaemia. This literature review assesses the various bodyweight gain liabilities associated with atypical antipsychotics, as well as the effects of bodyweight gain on quality of life. The issue of prevention and management of this often neglected adverse effect is also examined. Most studies reviewed indicate that clozapine and olanzapine are associated with more bodyweight gain than the other atypical antipsychotics. There are potential factors that place certain patients at greater risk for bodyweight gain, including low pretreatment body mass index, young age and being of female gender. Furthermore, bodyweight gain associated with the use of atypical antipsychotics has been reported to be associated with clinical improvement, although this has not been substantiated widely. It is unclear whether increased medical comorbidity, including diabetes mellitus, coronary artery disease and/or elevated triglyceride levels, is secondary to the bodyweight gain associated with atypical antipsychotics, or the result of the agents themselves. A patient's quality of life may be greatly affected by excessive bodyweight gain; either by increased comorbid medical illness, an increased relapse rate associated with noncompliance, or the social stigma associated with being obese. However, most studies reveal that treatment with atypical antipsychotic medications is associated with improved quality of life compared with that achieved with conventional antipsychotic medications. Because bodyweight is an important health risk associated with atypical antipsychotics, prevention and effective management of bodyweight are paramount in preventing comorbid medical illness, relapse and possible noncompliance.

Prevalence of obesity in adolescent and young adult patients with and without schizophrenia and in relationship to antipsychotic medication

The prevalence of obesity in inpatients of a German psychiatric rehabilitation center for adolescents and young adults (mean age 19.5 years) is assessed and set into relationship to diagnosis and medication regimen. In a cross-sectional naturalistic study body weights and heights of 151 inpatients, 109 of whom presented with ICD-10 schizophrenia spectrum disorders, were measured for the calculation of body mass indices (BMI, kg/m2); current medication regimen including the duration of treatment was assessed from medical records. BMIs were plotted into gender- and age-specific BMI-percentiles representative for the German population. Among the whole study population, obesity (BMI > or =90th percentile) was apparent in 44/98 (45%) of the male and in 31/53 (59%) of the female inpatients (overall: 50%). With respect to schizophrenia spectrum disorders, 36/70 (51%) males and 25/39 (64%) females (overall: 56%) were obese in contrast to 14/42 (33%) among the individuals without schizophrenia. Set into relationship to the treatment groups, the prevalence rates of obesity were 64% in patients treated with clozapine (n=69), 56% for other atypical antipsychotics (olanzapine, sulpiride, risperidone; n=27), 30% for classic antipsychotics (haloperidol, flupentixol, perazine; n=20) and 28% for the currently drug-free group (n=25). Together with other published findings in adults, these results suggest an increased prevalence of obesity among young patients with schizophrenia and especially among patients chronically treated with atypical antipsychotics.

Bodyweight gain with atypical antipsychotics. A comparative review

The atypical antipsychotics have been shown to have superior efficacy compared with typical antipsychotics such as haloperidol, particularly in the treatment of negative symptoms of schizophrenia. Furthermore, they induce less extrapyramidal effects. However, following clinical use, marked bodyweight gain has been frequently observed with some of the atypical antipsychotic drugs. In order to examine and compare the frequency, amount and conditions of bodyweight gain during treatment with atypical antipsychotics, studies concerning bodyweight gain with these agents were identified through a MEDLINE search from 1966 to March 2000. Although comparison is limited by the different designs and recruitment procedures of the reviewed studies, the available data support the notion that the frequency as well as the amount of bodyweight gain is high in patients treated with olanzapine (average bodyweight gain 2.3 kg/month), clozapine (1.7 kg/month), quetiapine (1.8 kg/month), and possibly also zotepine (2.3 kg/month). Moderate changes in bodyweight have been observed in the treatment with risperidone (average bodyweight gain 1.0 kg/month). Ziprasidone seems to induce only slight bodyweight changes (0.8 kg/month). Bodyweight gain most frequently occurs in the first 12 weeks of treatment. Patients who were underweight at the beginning of treatment are at highest risk of gaining bodyweight. The underlying pathomechanism still remains largely unclear. The relative receptor affinities of the atypical antipsychotics for histamine H1 receptors as well as the ratio of their affinity for serotonin 5-HT2 and dopamine D2 receptors appear to be the most robust correlate of bodyweight gain. Furthermore, the induction of leptin secretion may have an important impact on bodyweight gain in patients treated with atypical antipsychotics. Although many questions concerning the pathogenesis of bodyweight gain remain unresolved, this adverse effect has to be taken into consideration when prescribing the atypical antipsychotics, particularly in view its affect on compliance during long term treatment and the long term effects of obesity on mortality and morbidity.

Weight gain: side effect of atypical neuroleptics?

During clinical experience with the "atypical" neuroleptic drugs clozapine, risperidone, and zotepine, some patients have shown a marked weight gain. To prove whether weight gain is a relevant side effect of atypical neuroleptics, the charts of all patients admitted with DSM-III-R diagnoses of schizophrenia, schizoaffective disorder, or delusional disorder in the years 1991 to 1995 were evaluated. A retrospective chart review was performed, which included all patients who were treated longer than 2 weeks with a single neuroleptic. The data analysis showed that weight gain must be considered as a common side effect of atypical neuroleptics (clozapine, risperidone, sulpiride, or zotepine). The mean weight gain (3.1, 1.5, 1.9, or 4.3 kg, respectively) was significantly higher than that of patients treated with "classic" neuroleptics (mean, 0.0-0.5 kg) (Kruskal-Wallis, p = 0.01). Young and not obese patients show the highest weight increase. Because weight gain occurs in the first weeks of treatment, particularly in previously untreated subjects, this side effect has to be considered in view of compliance with long-term neuroleptic medication.

Body weight gain induced by antipsychotic drugs: mechanisms and management

Long-term administration of typical and atypical antipsychotic drugs (AP) induces excessive weight gain which afflicts up to 50% of patients, impairs health and interferes with treatment compliance. Basic and clinical research has shown that AP may affect body weight through diverse mechanisms. Increased appetite is probably related to the interaction of AP with neuronal receptors to dopamine, serotonin and histamine. Additional metabolic-endocrine disruption of weight regulation may be related to the effects of AP-induced hyperprolactinaemia on gonadal-adrenal steroids and insulin sensitivity. In humans, programmed physical activity, dietary restriction, anorectic agents, and drugs that counteract hyperprolactinaemia have been shown to be successful in a limited number of studies. Two novel strategies could expand the available therapeutic options. First, in preclinical experiments in female rats the estradiol antagonist/agonist drug tamoxifen or estradiol itself have been shown to completely prevent the obesity provoked by the AP sulpiride, and to induce an endocrine-metabolic milieu that seems to counteract AP-induced obesity. Secondly, it has also been shown that oral antihyperglycaemic agents such as metformin may decrease body weight and counteract insulin resistance and hyperinsulinaemia which is correlated with several metabolic abnormalities in obese subjects. Lastly, estradiol replacement, tamoxifen and/or antihyperglycaemic agents are not devoid of significant side-effects, and these drugs have not been tested in obese psychiatric patients. Therefore, further research is needed before their clinical use may be recommended.

Combination treatment with clozapine and paroxetine in schizophrenia: safety and tolerability data from a prospective open clinical trial

Clozapine is a drug with many side effects, some of them with potentially hazardous outcome (e.g. seizures, agranulocytosis), if not carefully monitored. It has been shown that the metabolism of clozapine may be affected by concomitant treatment with selective serotonin reuptake inhibitors (SSRIs), while there have been reports of improved efficacy on negative symptomatology of clozapine in combination with SSRIs. Therefore, this prospective open clinical trial was performed to investigate the safety and tolerability of the coadministration of clozapine and paroxetine under control of serum concentrations of clozapine and its metabolites and the effect of this combination treatment on psychopathological outcome was evaluated. A total of 14 patients suffering from schizophrenia or schizodepressive disorder with predominant negative symptomatology were included. The duration of the study was at least 6 weeks for each patient. Initial treatment was a monotherapy with clozapine at a daily dose of 2.5 mg/kg weight. After two measurements of serum concentrations of clozapine and metabolites during steady state conditions, an add-on therapy with 20 mg paroxetine was initiated. No concomitant medication was allowed. The main finding of our prospective study was that addition of paroxetine to a monotherapy with clozapine was a well tolerated medication that did not give rise to new clinically relevant side effects. After addition of paroxetine the serum concentrations of clozapine and its major metabolites remained virtually constant. The results of the psychopathological measurements indicated a further clinical improvement, although the small open study could not test for efficacy.