Pharmacological interventions for antipsychotic-induced weight gain in schizophrenia: A network meta-analysis

OBJECTIVE

Antipsychotic-induced weight gain (AIWG) is a significant but frequently neglected adverse effect of first- and second-generation antipsychotic therapy, which may lead to cardiovascular disturbances. The present network meta-analysis (NMA) was conducted to evaluate and compare the effects of available treatment options in antipsychotic-induced weight gain (AIWG).

METHODS

The data was extracted from 68 relevant clinical trials after a literature search on MEDLINE/PubMed, Embase, Scopus, Cochrane databases and clinical trial registries. Random-effects Bayesian NMA was done to pool the effects across the interventions for the change in body weight from baseline. A network graph was built, a consistency model was run, node split analysis was performed, treatments were ranked as per the SUCRA score and meta-regression was done for the duration of therapy, baseline body weight and treatment strategy as the predictor variables. Finally, the results were sorted based on the certainty of evidence.

RESULTS

The drugs showing significant reduction in body weight in order of magnitude of effect size include sibutramine 10 mg (-8.0 kg; -16. to -0.21), metformin 750 mg + lifestyle modification (-7.5 kg; -12 to -2.8), topiramate 200 mg (-7 kg; -10 to -3.4), metformin 750 mg (-5.7 kg; -9.3 to -2.1), topiramate 100 mg (-5.7 kg; -8.8 to -2.5), topiramate 50 mg (-5.2 kg; -10 to -0.57), liraglutide 1.8 mg (-5.2 kg; -10., -0.080), sibutramine 15 mg (-4.5 kg; -8.9 to -0.59), nizatidine 300 mg (-3.0 kg; -5.9 to -0.23) and metformin 1000 mg (-2.3 kg; -4.6 to -0.0046). There was no effect of duration of follow-up, baseline body weight and, preventive versus therapeutic strategy on weight reduction in AIWG.

CONCLUSION

Metformin 750 mg with lifestyle modification was the most effective treatment for AIWG, followed by topiramate 200 mg, metformin 750 mg, and topiramate 100 mg with moderate certainty of evidence.

Pharmacological Interventions of Atypical Antipsychotics Induced Weight Gain in the Pediatric Population: A Systemic Review of Current Evidence

To systematically review studies evaluating pharmacological treatment intervention of the atypical antipsychotic induced weight gain in the pediatric population and summarize the current evidence of the pharmacological treatment. According to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, we searched the various databases Medline, PubMed, PubMed central (PMC), CINAHL, and clinicaltrial.gov. until Jan 30th, 2022 for relevant clinical studies. Medical subject heading (MeSH) terms or keywords were used, "Body Weight," "Weight Gain," "Weight Loss," "Body Weight Maintenance," "Pediatric Obesity" in "Pediatrics," "Adolescent," "Child" in context of "Antipsychotic Agents" and "Drug Therapy," "Therapeutics," "Treatment Outcome," "Early Medical Intervention." We used the PICO algorithm for our search (Population, Intervention, Comparison, Outcomes, and Study Design) framework. The initial search included 746 articles, nine studies were ultimately selected in the final qualitative review. We included relevant clinical reviews, case series, and randomized clinical trials that evaluated pharmacological intervention for antipsychotic-induced weight gain in the pediatric population. Non-peer-reviewed, non-human, non-English languages article was excluded. Metformin is the most studied medication for antipsychotic-induced weight gain in children. Three studies have shown that adding Metformin to the antipsychotics can significantly reduce the body weight and body mass index with mild transient side effects. Other adjunct medications like topiramate, amantadine, betahistine, or melatonin vary greatly in mitigating weight with various side effects. Lifestyle modification is the first step in dealing with AIWG, but the result is inconsistent. Avoiding the use of antipsychotic in children is preferred. Adding an adjuvant medication to the antipsychotic could prevent or mitigate their negative metabolic effect on the body weight and body mass index. Metformin has the most evidence, topiramate, betahistine, amantadine, and melatonin is possible alternatives in the pediatric patient without changing their antipsychotic medication. Other viable options show some benefits but need further clinical studies to establish efficacy and safety.

Pharmacological interventions for prevention of weight gain in people with schizophrenia

BACKGROUND

Antipsychotic-induced weight gain is an extremely common problem in people with schizophrenia and is associated with increased morbidity and mortality. Adjunctive pharmacological interventions may be necessary to help manage antipsychotic-induced weight gain. This review splits and updates a previous Cochrane Review that focused on both pharmacological and behavioural approaches to this problem.

OBJECTIVES

To determine the effectiveness of pharmacological interventions for preventing antipsychotic-induced weight gain in people with schizophrenia.

SEARCH METHODS

The Cochrane Schizophrenia Information Specialist searched Cochrane Schizophrenia's Register of Trials on 10 February 2021. There are no language, date, document type, or publication status limitations for inclusion of records in the register.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that examined any adjunctive pharmacological intervention for preventing weight gain in people with schizophrenia or schizophrenia-like illnesses who use antipsychotic medications.

DATA COLLECTION AND ANALYSIS

At least two review authors independently extracted data and assessed the quality of included studies. For continuous outcomes, we combined mean differences (MD) in endpoint and change data in the analysis. For dichotomous outcomes, we calculated risk ratios (RR). We assessed risk of bias for included studies and used GRADE to judge certainty of evidence and create summary of findings tables. The primary outcomes for this review were clinically important change in weight, clinically important change in body mass index (BMI), leaving the study early, compliance with treatment, and frequency of nausea. The included studies rarely reported these outcomes, so, post hoc, we added two new outcomes, average endpoint/change in weight and average endpoint/change in BMI.

MAIN RESULTS

Seventeen RCTs, with a total of 1388 participants, met the inclusion criteria for the review. Five studies investigated metformin, three topiramate, three H2 antagonists, three monoamine modulators, and one each investigated monoamine modulators plus betahistine, melatonin and samidorphan. The comparator in all studies was placebo or no treatment (i.e. standard care alone). We synthesised all studies in a quantitative meta-analysis. Most studies inadequately reported their methods of allocation concealment and blinding of participants and personnel. The resulting risk of bias and often small sample sizes limited the overall certainty of the evidence. Only one reboxetine study reported the primary outcome, number of participants with clinically important change in weight. Fewer people in the treatment condition experienced weight gains of more than 5% and more than 7% of their bodyweight than those in the placebo group (> 5% weight gain RR 0.27, 95% confidence interval (CI) 0.11 to 0.65; 1 study, 43 participants; > 7% weight gain RR 0.24, 95% CI 0.07 to 0.83; 1 study, 43 participants; very low-certainty evidence). No studies reported the primary outcomes, 'clinically important change in BMI', or 'compliance with treatment'. However, several studies reported 'average endpoint/change in body weight' or 'average endpoint/change in BMI'. Metformin may be effective in preventing weight gain (MD -4.03 kg, 95% CI -5.78 to -2.28; 4 studies, 131 participants; low-certainty evidence); and BMI increase (MD -1.63 kg/m2, 95% CI -2.96 to -0.29; 5 studies, 227 participants; low-certainty evidence). Other agents that may be slightly effective in preventing weight gain include H2 antagonists such as nizatidine, famotidine and ranitidine (MD -1.32 kg, 95% CI -2.09 to -0.56; 3 studies, 248 participants; low-certainty evidence) and monoamine modulators such as reboxetine and fluoxetine (weight: MD -1.89 kg, 95% CI -3.31 to -0.47; 3 studies, 103 participants; low-certainty evidence; BMI: MD -0.66 kg/m2, 95% CI -1.05 to -0.26; 3 studies, 103 participants; low-certainty evidence). Topiramate did not appear effective in preventing weight gain (MD -4.82 kg, 95% CI -9.99 to 0.35; 3 studies, 168 participants; very low-certainty evidence). For all agents, there was no difference between groups in terms of individuals leaving the study or reports of nausea. However, the results of these outcomes are uncertain given the very low-certainty evidence.

AUTHORS' CONCLUSIONS

There is low-certainty evidence to suggest that metformin may be effective in preventing weight gain. Interpretation of this result and those for other agents, is limited by the small number of studies, small sample size, and short study duration. In future, we need studies that are adequately powered and with longer treatment durations to further evaluate the efficacy and safety of interventions for managing weight gain.

Pharmacological Interventions to Treat Antipsychotic-Induced Dyslipidemia in Schizophrenia Patients: A Systematic Review and Meta Analysis

Introduction: Antipsychotic-induced dyslipidemia represents a common adverse effect faced by patients with schizophrenia that increases risk for developing further metabolic complications and cardiovascular disease. Despite its burden, antipsychotic-induced dyslipidemia is often left untreated, and the effectiveness of pharmacological interventions for mitigating dyslipidemia has not been well-addressed. This review aims to assess the effectiveness of pharmacological interventions in alleviating dyslipidemia in patients with schizophrenia. Methods: Medline, PsychInfo, and EMBASE were searched for all relevant English articles from 1950 to November 2020. Randomized placebo-controlled trials were included. Differences in changes in triglycerides, HDL cholesterol, LDL cholesterol, and VLDL cholesterol levels between treatment and placebo groups were meta-analyzed as primary outcomes. Results: Our review identified 48 randomized controlled trials that comprised a total of 3,128 patients and investigated 29 pharmacological interventions. Overall, pharmacological interventions were effective in lowering LDL cholesterol, triglycerides, and total cholesterol levels while increasing the levels of HDL cholesterol. Within the intervention subgroups, approved lipid-lowering agents did not reduce lipid parameters other than total cholesterol level, while antipsychotic switching and antipsychotic add-on interventions improved multiple lipid parameters, including triglycerides, LDL cholesterol, HDL cholesterol, and total cholesterol. Off label lipid lowering agents improved triglycerides and total cholesterol levels, with statistically significant changes seen with metformin. Conclusion: Currently available lipid lowering agents may not work as well in patients with schizophrenia who are being treated with antipsychotics. Additionally, antipsychotic switching, antipsychotic add-ons, and certain off label interventions might be more effective in improving some but not all associated lipid parameters. Future studies should explore novel interventions for effectively managing antipsychotic-induced dyslipidemia. Registration: PROSPERO 2020 CRD42020219982; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020219982.

Systematic review and exploratory meta-analysis of the efficacy, safety, and biological effects of psychostimulants and atomoxetine in patients with schizophrenia or schizoaffective disorder

OBJECTIVE

Our aim was to summarize the efficacy and safety of atomoxetine, amphetamines, and methylphenidate in schizophrenia.

METHODS

We undertook a systematic review, searching PubMed/Scopus/Clinicaltrials.gov for double-blind, randomized, placebo-controlled studies of psychostimulants or atomoxetine in schizophrenia published up to 1 January 2017. A meta-analysis of outcomes reported in two or more studies is presented.

RESULTS

We included 22 studies investigating therapeutic effects of stimulants (k=14) or measuring symptomatic worsening/relapse prediction after stimulant challenge (k=6). Six studies of these two groups plus one additional study investigated biological effects of psychostimulants or atomoxetine. No effect resulted from interventional studies on weight loss (k=1), smoking cessation (k=1), and positive symptoms (k=12), and no improvement was reported with atomoxetine (k=3) for negative symptoms, with equivocal findings for negative (k=6) and mood symptoms (k=2) with amphetamines. Attention, processing speed, working memory, problem solving, and executive functions, among others, showed from no to some improvement with atomoxetine (k=3) or amphetamines (k=6). Meta-analysis did not confirm any effect of stimulants in any symptom domain, including negative symptoms, apart from atomoxetine improving problem solving (k=2, standardized mean difference (SMD)=0.73, 95% CI=0.10-1.36, p=0.02, I2=0%), and trending toward significant improvement in executive functions with amphetamines (k=2, SMD=0.80, 95% CI=-1.68 to +0.08, p=0.08, I2=66%). In challenge studies, amphetamines (k=1) did not worsen symptoms, and methylphenidate (k=5) consistently worsened or predicted relapse. Biological effects of atomoxetine (k=1) and amphetamines (k=1) were cortical activation, without change in β-endorphin (k=1), improved response to antipsychotics after amphetamine challenge (k=2), and an increase of growth hormone-mediated psychosis with methylphenidate (k=2). No major side effects were reported (k=6).

CONCLUSIONS

No efficacy for stimulants or atomoxetine on negative symptoms is proven. Atomoxetine or amphetamines may improve cognitive symptoms, while methylphenidate should be avoided in patients with schizophrenia. Insufficient evidence is available to draw firm conclusions.

Primary care management of cardiovascular risk for people with severe mental illnesses: the Primrose research programme including cluster RCT

Background

Effective interventions are needed to prevent cardiovascular disease (CVD) in people with severe mental illnesses (SMI) because their risk of CVD is higher than that of the general population.

Objectives

(1) Develop and validate risk models for predicting CVD events in people with SMI and evaluate their cost-effectiveness, (2) develop an intervention to reduce levels of cholesterol and CVD risk in SMI and (3) test the clinical effectiveness and cost-effectiveness of this new intervention in primary care.

Design

Mixed methods with patient and public involvement throughout. The mixed methods were (1) a prospective cohort and risk score validation study and cost-effectiveness modelling, (2) development work (focus groups, updated systematic review of interventions, primary care database studies investigating statin prescribing and effectiveness) and (3) cluster randomised controlled trial (RCT) assessing the clinical effectiveness and cost-effectiveness of a new practitioner-led intervention, and fidelity assessment of audio-recorded appointments.

Setting

General practices across England.

Participants

All studies included adults with SMI (schizophrenia, bipolar disorder or other non-organic psychosis). The RCT included adults with SMI and two or more CVD risk factors.

Interventions

The intervention consisted of 8–12 appointments with a practice nurse/health-care assistant over 6 months, involving collaborative behavioural approaches to CVD risk factors. The intervention was compared with routine practice with a general practitioner (GP).

Main outcome measures

The primary outcome for the risk score work was CVD events, in the cost-effectiveness modelling it was quality-adjusted life-years (QALYs) and in the RCT it was level of total cholesterol.

Data sources

Databases studies used The Health Improvement Network (THIN). Intervention development work included focus groups and systematic reviews. The RCT collected patient self-reported and routine NHS GP data. Intervention appointments were audio-recorded.

Results

Two CVD risk score models were developed and validated in 38,824 people with SMI in THIN: the Primrose lipid model requiring cholesterol levels, and the Primrose body mass index (BMI) model with no blood test. These models performed better than published Cox Framingham models. In health economic modelling, the Primrose BMI model was most cost-effective when used as an algorithm to drive statin prescriptions. Focus groups identified barriers to, and facilitators of, reducing CVD risk in SMI including patient engagement and motivation, staff confidence, involving supportive others, goal-setting and continuity of care. Findings were synthesised with evidence from updated systematic reviews to create the Primrose intervention and training programme. THIN cohort studies in 16,854 people with SMI demonstrated that statins effectively reduced levels of cholesterol, with similar effect sizes to those in general population studies over 12–24 months (mean decrease 1.2 mmol/l). Cluster RCT: 76 GP practices were randomised to the Primrose intervention (n = 38) or treatment as usual (TAU) (n = 38). The primary outcome (level of cholesterol) was analysed for 137 out of 155 participants in Primrose and 152 out of 172 in TAU. There was no difference in levels of cholesterol at 12 months [5.4 mmol/l Primrose vs. 5.5 mmol/l TAU; coefficient 0.03; 95% confidence interval (CI) –0.22 to 0.29], nor in secondary outcomes related to cardiometabolic parameters, well-being or medication adherence. Mean cholesterol levels decreased over 12 months in both arms (–0.22 mmol/l Primrose vs. –0.39 mmol/l TAU). There was a significant reduction in the cost of inpatient mental health attendances (–£799, 95% CI –£1480 to –£117) and total health-care costs (–£895, 95% CI –£1631 to –£160; p = 0.012) in the intervention group, but no significant difference in QALYs (–0.011, 95% CI –0.034 to 0.011). A total of 69% of patients attended two or more Primrose appointments. Audiotapes revealed moderate fidelity to intervention delivery (67.7%). Statin prescribing and adherence was rarely addressed.

Limitations

RCT participants and practices may not represent all UK practices. CVD care in the TAU arm may have been enhanced by trial procedures involving CVD risk screening and feedback.

Conclusions

SMI-specific CVD risk scores better predict new CVD if used to guide statin prescribing in SMI. Statins are effective in reducing levels of cholesterol in people with SMI in UK clinical practice. This primary care RCT evaluated an evidence-based practitioner-led intervention that was well attended by patients and intervention components were delivered. No superiority was shown for the new intervention over TAU for level of cholesterol, but cholesterol levels decreased over 12 months in both arms and the intervention showed fewer inpatient admissions. There was no difference in cholesterol levels between the intervention and TAU arms, which might reflect better than standard general practice care in TAU, heterogeneity in intervention delivery or suboptimal emphasis on statins.

Future work

The new risk score should be updated, deployed and tested in different settings and compared with the latest versions of CVD risk scores in different countries. Future research on CVD risk interventions should emphasise statin prescriptions more. The mechanism behind lower costs with the Primrose intervention needs exploring, including SMI-related training and offering frequent support to people with SMI in primary care.

Trial registration

Current Controlled Trials ISRCTN13762819.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 7, No. 2. See the NIHR Journals Library website for further project information. Professor David Osborn is supported by the University College London Hospital NIHR Biomedical Research Centre and he was also in part supported by the NIHR Collaboration for Leadership in Applied Health Research and Care (CLAHRC) North Thames at Barts Health NHS Trust.

Antipsychotics-induced metabolic alterations: Recounting the mechanistic insights, therapeutic targets and pharmacological alternatives

Atypical antipsychotics (AAPs) are the drug of choice in the management of mental illnesses by virtue of their advantage over typical antipsychotics i.e. least tendency of producing extrapyramidal motor symptoms (EPS) or pseudoparkinsonism. Despite the clinical efficacy, AAPs produces troublesome adverse effects, particularly hyperphagia, hyperglycemia, dyslipidemia weight gain, diabetes mellitus, insulin resistance and QT prolongation which further develops metabolic and cardiac complications with subsequent reduction in life expectancy, poor patient compliance, and sudden death. AAPs-induced weight gain and metabolic alterations are increasing at an alarming rate and became an utmost matter of concern for psychopharmacotherapy. Diverse underlying mechanisms have been explored such as the interaction of AAPs with neurotransmitter receptors, alteration in food reward anticipation behavior, altered expressions of hypothalamic orexigenic and anorexigenic neuropeptides, histamine H₁ receptor-mediated hypothalamic AMP-activated protein kinase (AMPK) activation, increased blood leptin, ghrelin, pro-inflammatory cytokines. Antipsychotics induced imbalance in energy homeostasis, reduction in energy expenditure which is linked to altered expression of uncoupling proteins (UCP-1) in brown adipose tissue and reduced hypothalamic orexin expressions are emerging insights. In addition, alteration in gut-microbiota and subsequent inflammation, dyslipidemia, obesity, and diabetes after AAPs treatment are also associated with weight gain and metabolic alterations. Oral hypoglycemics and lipid-lowering drugs are mainly prescribed in the clinical management of weight gain associated with AAPs while many other pharmacological and nonpharmacological interventions also have been explored in different clinical and preclinical studies. In this review, we critically discuss the current scenario, mechanistic insights, biomarkers, and therapeutic alternatives for metabolic alterations associated with antipsychotics.

Selective noradrenaline reuptake inhibitors for schizophrenia

BACKGROUND

Schizophrenia is frequently a chronic and disabling illness with a heterogeneous range of symptoms. The positive symptoms usually respond to antipsychotics but the cognitive and negative symptoms of schizophrenia are difficult to treat with conventional antipsychotics and significantly impact on quality of life and social outcomes. Selective noradrenaline reuptake inhibitors (NRIs) increase prefrontal dopamine and noradrenaline levels without significantly affecting subcortical dopamine levels, making them an attractive candidate for treating cognitive and negative symptoms.

OBJECTIVES

To investigate the effects of selective noradrenaline reuptake inhibitors (NRIs), compared with a placebo or control treatment, for people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Trials Register (up to 7 February 2017) which is based on regular searches of MEDLINE, Embase, CINAHL, BIOSIS, AMED, PubMed, PsycINFO, and registries of clinical trials. There are no language, date, document type, or publication status limitation for inclusion of records into the register. We inspected references of all included studies for further relevant studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing NRIs with either a control treatment or placebo for people with schizophrenia or related disorders (such as schizoaffective disorder) by any means of diagnosis. We included trials that met our selection criteria and provided useable information.

DATA COLLECTION AND ANALYSIS

We independently inspected all citations from searches, identified relevant abstracts, and independently extracted data from all included studies. For binary data we calculated risk ratio (RR), for continuous data we calculated mean difference (MD), and for cognitive outcomes we derived standardised mean difference (SMD) effect sizes, all with 95% confidence intervals (CI) and using a random-effects model. We assessed risk of bias for the included studies and used the GRADE approach to produce a 'Summary of findings' table which included our prespecified main outcomes of interest.

MAIN RESULTS

Searching identified 113 records. We obtained the full text of 48 of these records for closer inspection. Sixteen trials, randomising a total of 919 participants are included. The majority of trials included adults with schizophrenia or similar illness who were inpatients, and while they were poorly characterised, most appeared to include patients with a chronic presentation. The intervention NRI in nine of the 16 trials was reboxetine, with atomoxetine and viloxazine used in the remaining trials. 14 trials compared NRIs with placebo. Only two trials provided data to compare NRIs against an active control and both compared reboxetine to citalopram but at 4 weeks and 24 weeks respectively so they could not be combined in a meta-analysis.One trial was described as 'open' and we considered it to be at high risk of bias for randomisation and blinding, three trials were at high risk of bias for attrition, six for reporting, and two for other sources of bias. Our main outcomes of interest were significant response or improvement in positive/negative mental state, global state and cognitive functioning, average cognitive functioning scores, significant response or improvement in quality of life and incidence of nausea. All data for main outcomes were short term.NRIs versus placeboMental state results showed significantly greater rates of improvement in negative symptoms scores (1 RCT, n = 50; RR 3.17, 95% CI 1.52 to 6.58; very low quality evidence) with NRIs on the PANSS negative. No data were reported for significant response or improvement in positive symptoms, but average endpoint PANSS positive scores were available and showed no difference between NRIs and placebo (5 RCTs, n = 294; MD -0.16, 95% CI -0.96 to 0.63; low-quality evidence). Improvement in clinical global status was similar between groups (1 RCT, n = 28; RR 0.99, 95% CI 0.45 to 2.20; very low quality evidence). Significant response or improvement in cognitive functioning data were not reported. Average composite cognitive scores showed no difference between NRIs and placebo (4 RCTs, n = 180; SMD 0.04, 95% CI -0.28 to 0.36; low-quality evidence). Significant response or improvement in quality of life data were not reported, however average endpoint scores from the GQOLI-74 were reported. Those receiving NRIs had better quality of life scores compared to placebo (1 RCT, n = 114; MD 9.36, 95% CI 7.89 to 10.83; very low quality evidence). All-cause withdrawals did not differ between the treatment groups (8 RCTs, n = 401, RR 0.94 95% CI 0.63 to 1.39; moderate-quality evidence). Rates of nausea were not greater with NRIs (3 RCTs, n = 176; RR 0.49, 95% CI 0.10 to 2.41; low-quality evidence).

AUTHORS' CONCLUSIONS

Our results provide tentative very low quality evidence that compared to placebo, NRIs (specifically reboxetine) may have a benefit on the negative symptoms of schizophrenia. Limited evidence also suggests that NRIs have no effect on the positive symptoms of schizophrenia or cognitive functioning. NRIs appear generally well tolerated with no real differences in adverse effects such as nausea noted between NRIs and placebo. However, these results are based on short-term follow-up and are poor quality - there is need for more good-quality evidence. A large RCT of reboxetine over a longer period of time, focusing specifically on negative and cognitive symptoms as well as more detailed and comprehensive reporting of outcomes, including adverse events, is required.

Antipsychotic-associated weight gain: management strategies and impact on treatment adherence

Antipsychotic-induced weight gain is a major management problem for clinicians. It has been shown that weight gain and obesity lead to increased cardiovascular and cerebrovascular morbidity and mortality, reduced quality of life and poor drug compliance. This narrative review discusses the propensity of various antipsychotics to cause weight gain, the pharmacologic and nonpharmacologic interventions available to counteract this effect and its impact on adherence. Most antipsychotics cause weight gain. The risk appears to be highest with olanzapine and clozapine. Weight increases rapidly in the initial period after starting antipsychotics. Patients continue to gain weight in the long term. Children appear to be particularly vulnerable to antipsychotic-induced weight gain. Tailoring antipsychotics according to the needs of the individual and close monitoring of weight and other metabolic parameters are the best preventive strategies at the outset. Switching to an agent with lesser tendency to cause weight gain is an option, but carries the risk of relapse of the illness. Nonpharmacologic interventions of dietary counseling, exercise programs and cognitive and behavioral strategies appear to be equally effective in individual and group therapy formats. Both nonpharmacologic prevention and intervention strategies have shown modest effects on weight. Multiple compounds have been investigated as add-on medications to cause weight loss. Metformin has the best evidence in this respect. Burden of side effects needs to be considered when prescribing weight loss medications. There is no strong evidence to recommend routine prescription of add-on medication for weight reduction. Heterogeneity of study methodologies and other confounders such as lifestyle, genetic and illness factors make interpretation of data difficult.

A systematic review and meta-analysis of randomised controlled trials of treatments for clozapine-induced obesity and metabolic syndrome

Metabolic complications are commonly found in people treated with clozapine. Reviews on the management of this problem have generally drawn conclusions by grouping different types of studies involving patients treated with various different antipsychotics. We carried out a systematic review and meta-analysis of pharmacological and non-pharmacological treatments for clozapine-induced obesity or metabolic syndrome. Two researchers independently searched PubMed and Embase for randomised controlled trials (RCTs) of treatments for clozapine-induced obesity or metabolic syndrome. All other types of studies were excluded. We only included RCTs where more than 50% of participants were taking clozapine. We identified 15 RCTs. Effective pharmacological treatments for clozapine-induced obesity and metabolic syndrome include metformin, aripiprazole, and Orlistat (in men only). Meta-analysis of three studies showed a robust effect of metformin in reducing body mass index and waist circumference but no effects on blood glucose, triglyceride levels, or HDL levels. In addition, there is limited evidence for combined calorie restriction and exercise as a non-pharmacological alternative for the treatment of clozapine-induced obesity, but only in an in-patient setting. Rosiglitazone, topiramate, sibutramine, phenylpropanolamine, modafinil, and atomoxetine have not shown to be beneficial, despite reports of efficacy in other populations treated with different antipsychotics. We conclude that randomised-controlled trial data support the use of metformin, aripiprazole, and Orlistat (in men only) for treating clozapine-induced obesity. Calorie restriction in combination with an exercise programme may be effective as a non-pharmacological alternative. Findings from trials in different populations should not be extrapolated to people being treated with clozapine.

Classification of Therapeutic and Experimental Drugs for Brown Adipose Tissue Activation: Potential Treatment Strategies for Diabetes and Obesity

OBJECTIVE

Increasing efforts are being made towards pharmacologic activation of brown adipose tissue (BAT) in animals and humans for potential use in the treatment of obesity and diabetes. We and others have reported a number of animal studies using either experimental or therapeutic drugs. There are now efforts to translate these findings to human studies. The goal of this review is to evaluate the various drugs currently being used that have the potential for BAT activation.

METHODS

Drugs were classified into 4 classes based on their mechanism of action. Class 1 drugs include the use of β3 adrenoceptor agonists for BAT activation. Class 2 drugs include drugs that affect norepinephrine levels and activate BAT with the potential of reducing obesity. Class 3 includes activators of peroxisome proliferator-activated receptor-γ in pursuit of lowering blood sugar, weight loss and diabetes and finally Class 4 includes natural products and other emerging drugs with limited information on BAT activation and their effects on diabetes and weight loss.

RESULTS

Class 1 drugs are high BAT activators followed by Class 2 and 3. Some of these drugs have now been extended to diabetes and obesity animal models and human BAT studies. Drugs in Class 3 are used clinically for Type 2 diabetes, but the extent of BAT involvement is unclear.

CONCLUSION

Further studies on the efficacy of these drugs in diabetes and measuring their effects on BAT activation using noninvasive imaging will help in establishing a clinical role of BAT.

Metabolic syndrome and obesity among users of second generation antipsychotics: A global challenge for modern psychopharmacology

Second generation antipsychotics (SGAs), such as clozapine, olanzapine, risperidone and quetiapine, are among the most effective therapies to stabilize symptoms schizophrenia (SZ) spectrum disorders. In fact, clozapine, olanzapine and risperidone have improved the quality of life of billions SZ patients worldwide. Based on the broad spectrum of efficacy and low risk of extrapyramidal symptoms displayed by SGAs, some regulatory agencies approved the use of SGAs in non-schizophrenic adults, children and adolescents suffering from a range of neuropsychiatric disorders. However, increasing number of reports have shown that SGAs are strongly associated with accelerated weight gain, insulin resistance, diabetes, dyslipidemia, and increased cardiovascular risk. These metabolic alterations can develop in as short as six months after the initiation of pharmacotherapy, which is now a controversial fact in public disclosure. Although the percentage of schizophrenic patients, the main target group of SGAs, is estimated in only 1% of the population, during the past ten years there was an exponential increase in the number of SGAs users, including millions of non-SZ patients. The scientific bases of SGAs metabolic side effects are not yet elucidated, but the evidence shows that the activation of transcriptional factor SRBP1c, the D1/D2 dopamine, GABA2 and 5HT neurotransmitions are implicated in the SGAs cardiovascular toxicity. Polypharmacological interventions are either non- or modestly effective in maintaining low cardiovascular risk in SGAs users. In this review we critically discuss the clinical and molecular evidence on metabolic alterations induced by SGAs, the evidence on the efficacy of classical antidiabetic drugs and the emerging concept of antidiabetic polyphenols as potential coadjutants in SGA-induced metabolic disorders.

Treatment of clozapine-associated weight gain: a systematic review

PURPOSE

Clozapine is an antipsychotic drug with superior efficacy in treatment-resistant schizophrenia. Clozapine is associated with a low likelihood of extrapyramidal symptoms and other neurological side-effects but a high propensity to induce weight gain and general metabolic dysregulation. Various pharmacological and behavioral treatment approaches for reducing clozapine-associated weight gain exist in the literature; however, there are currently no clear clinical guidelines as to which method is preferred. The aim of the current review is to systematically summarize studies that have studied both pharmacological and non-pharmacological interventions to attenuate or reverse clozapine-associated weight gain.

METHODS

A systematic review of EMBASE and MEDLINE databases of all articles published prior to January 2014 was conducted. Seventeen studies were identified as meeting inclusion criteria and included in the review.

RESULTS

Aripiprazole, fluvoxamine, metformin, and topiramate appear to be beneficial; however, available data are limited to between one and three randomized controlled trials per intervention. Orlistat shows beneficial effects, but in males only. Behavioral and nutritional interventions also show modest effects on decreasing clozapine-associated weight gain, although only a small number of such studies exist.

CONCLUSIONS

While a number of pharmacological interventions can produce modest weight loss, each may be associated with negative side effects, which should be considered before beginning treatment. Given the pressing need to improve cardiometabolic health in most clozapine-treated patients, substantially more research is needed to develop sound clinical practice guidelines for the treatment of clozapine-associated weight gain.

Pharmacological strategies to counteract antipsychotic-induced weight gain and metabolic adverse effects in schizophrenia: a systematic review and meta-analysis

BACKGROUND

Antipsychotic-induced metabolic adversities are often difficult to manage. Using concomitant medications to counteract these adversities may be a rational option.

OBJECTIVE

To systematically determine the effectiveness of medications to counteract antipsychotic-induced metabolic adversities in patients with schizophrenia.

DATA SOURCES

Published articles until November 2013 were searched using 5 electronic databases. Clinical trial registries were searched for unpublished trials.

STUDY SELECTION

Double-blind randomized placebo-controlled trials focusing on patients with schizophrenia were included if they evaluated the effects of concomitant medications on antipsychotic-induced metabolic adversities as a primary outcome.

DATA EXTRACTION

Variables relating to participants, interventions, comparisons, outcomes, and study design were extracted. The primary outcome was change in body weight. Secondary outcomes included clinically relevant weight change, fasting glucose, hemoglobin A1c, fasting insulin, insulin resistance, cholesterol, and triglycerides.

DATA SYNTHESIS

Forty trials representing 19 unique interventions were included in this meta-analysis. Metformin was the most extensively studied drug in regard to body weight, the mean difference amounting to -3.17 kg (95% CI: -4.44 to -1.90 kg) compared to placebo. Pooled effects for topiramate, sibutramine, aripiprazole, and reboxetine were also different from placebo. Furthermore, metformin and rosiglitazone improved insulin resistance, while aripiprazole, metformin, and sibutramine decreased blood lipids.

CONCLUSION

When nonpharmacological strategies alone are insufficient, and switching antipsychotics to relatively weight-neutral agents is not feasible, the literature supports the use of concomitant metformin as first choice among pharmacological interventions to counteract antipsychotic-induced weight gain and other metabolic adversities in schizophrenia.

Weight considerations in psychotropic drug prescribing and switching

Our review describes potential weight-altering effects of psychotropic medications (antipsychotics, antidepressants, anti-anxiety medications, mood stabilizers, sedative-hypnotics, medications for attention-deficit/hyperactivity disorder, and other psychotropic medications) and offers guidance on switching a medication if its weight-altering effect becomes problematic. For second-generation antipsychotics, the risk of weight gain is high with clozapine and olanzapine, low with amisulpride, aripiprazole, and ziprasidone, and medium with other second-generation antipsychotics. Switching from a high-risk antipsychotic to a low-risk antipsychotic usually mitigates or reverses weight gain. For second-generation antidepressants, there may be modest weight loss with bupropion and modest weight gain with mirtazapine and paroxetine. Other second-generation antidepressants are weight neutral but individual variations can occur. If significant change in weight occurs, switching to or adding a low-risk second-generation antidepressant should be considered. Mood stabilizers include lithium, valproate, carbamazepine, lamotrigine, oxcarbazepine, and most second-generation antipsychotics. Risk of weight gain is high with lithium and valproate and low with carbamazepine, lamotrigine, and oxcarbazepine. Given the complexity of bipolar disorder and its management, a switch of a mood stabilizer would be best done by a psychiatrist. Benzodiazepines, non-benzodiazepine and melatonergic hypnotics, doxepin, and trazodone are weight neutral. Diphenhydramine may cause weight-gain and can be switched to a weight-neutral hypnotic if needed. Stimulants can cause varying degrees of weight loss and switching to atomoxetine or bupropion may reverse this problem. If that fails, switching to clonidine or guanfacine can be tried. Switching must be evidence-based and take into account status of the condition being treated, efficacy, side effect profile, potential drug-drug interactions, required laboratory monitoring and cost of the drug(s) being considered, and patient's pregnancy status or plan. Non-pharmacological interventions both for mental disorders and overweight/obesity must be fully availed.

Efficacy and safety of noradrenalin reuptake inhibitor augmentation therapy for schizophrenia: a meta-analysis of double-blind randomized placebo-controlled trials

BACKGROUND

We performed an updated meta-analysis of noradrenalin reuptake inhibitor (NRI) augmentation therapy in patients with schizophrenia treated with antipsychotics based on a previous meta-analysis (Singh et al.).

METHODS

PubMed, Cochrane Library databases, and PsycINFO citations were searched from their inception to June 10, 2013 without language restrictions. We conducted a systematic review and meta-analysis of individual patient data from randomized controlled trials comparing NRI augmentation therapy with placebo. The outcome measure for efficacy was the psychopathology of schizophrenia and the measures for safety were discontinuation rate and several side effects. We used standardized mean differences (SMD) to estimate treatment effects for continuous variables, and risk ratios (RR) for dichotomous variables, with their 95% confidence intervals (CIs). A random-effects model was used.

RESULTS

Nine studies (4 atomoxetine studies, 3 reboxetine studies, 1 reboxetine-betahistine combination study and 1 mazindol study, total n=298) were identified. No statistically significant effects of NRI augmentation therapy on overall (p=0.90), positive (p=0.81), and negative (p=0.89) symptoms were found. NRI augmentation therapy was marginally superior to placebo for efficacy of depressive symptoms (SMD=-1.08, p=0.05). Dropout due to all-cause (p=0.70), inefficacy (p=0.64), or adverse events (p=0.18) was similar in both groups. NRI augmentation therapy showed a significantly lower increase or larger reduction in body weight than placebo (SMD=-0.47, p=0.03). Reboxetine augmentation was associated with less weight gain that placebo in antipsychotic treated schizophrenia patients (SMD=-0.78, p=0.0001).

CONCLUSION

NRIs may exert an effect on depressive symptoms, and seem to be well-tolerated treatments.

The effect of zonisamide on antipsychotic-associated weight gain in patients with schizophrenia: a randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

Many patients with schizophrenia suffer from metabolic symptoms and weight gain in which predispose them to obesity, diabetes, and cardiovascular problems. This trial examines the efficacy and safety of zonisamide on weight and body mass index in patients with schizophrenia being administered with atypical antipsychotics.

METHOD

In this 10-week, double blind randomized placebo controlled clinical trial, forty one patients with schizophrenia diagnosed according to DSM-IV-TR criteria who were taking a stable dose of atypical antipsychotic are allocated into one of the two groups of zonisamide or placebo group. Weight, body mass index, waist circumference, and adverse effects were assessed.

RESULTS

The two groups were not statistically different regarding baseline characteristics on age, gender, education, diagnosis, weight, body mass index, daily cigarette smoking, and the duration of illness. After 10 weeks, the patients in the placebo group had significantly gained weight, while the patients in the zonisamide group lost weight (mean=1.9, SD=2.2 versus mean=-1.1 kg, SD=1.4). The changes of body mass index in the two groups were significantly different. Body mass index decreased in the zonisamide group (mean=-0.3, SD=0.4) while it increased in the placebo group (mean=2.2, SD=6.9). There was a significance difference between the two groups regarding waist circumference at the end of trial (P<0.0001), too. The waist increased in the placebo group while it decreased in the zonisamide group (mean=1.1, SD=1.7 versus mean=-0.7, SD=1.2, respectively), as well. The frequencies of adverse effects were not significantly different between the two groups and zonisamide was tolerated well.

CONCLUSION

Zonisamide as an adjuvant treatment is tolerated well and markedly affect on the weight loss of patients with schizophrenia being treated with atypical antipsychotics.

Participants with schizophrenia retain the information necessary for informed consent during clinical trials

OBJECTIVE

Cognitive impairment is a characteristic of schizophrenia. This impairment may affect the retention of information required for ongoing knowledgeable participation in clinical trials. This study monitored retention of study-related knowledge-including assessment of therapeutic misconception-in people with stable, DSM-IV schizophrenia during participation in placebo-controlled clinical trials of adjunctive agents. Stability was defined as being on an antipsychotic with no change in medication or dose over the previous 4 weeks.

METHOD

This longitudinal study assessed retention of clinical trial-related consent information. Individuals enrolling in 1 of 8 clinical trials were approached for participation. Participants came from research clinics and community mental health centers. At baseline, clinical trial consent forms were reviewed and study knowledge assessed. Participants were randomized to follow-up assessments at weeks 1, 4, and 8; weeks 4 and 8; or at week 8 only. Clinical trial consent forms were not rereviewed at any follow-up visit.

RESULTS

Fifty-nine participants were enrolled; analysis included 52 participants with at least 1 follow-up visit. Study knowledge did not decrease meaningfully in any group. Therapeutic misconception was not observed in participants during the study. The group assessed most frequently demonstrated significant improvement over baseline (t44 = 3.43, P = .001). Retention of study knowledge was not related to symptoms but had a weak correlation with cognitive capacity (R = 0.28, P = .07). Performance did not differ between participants from research clinics and those from community mental health centers.

CONCLUSIONS

Clinically stable people with schizophrenia enrolling in a placebo-controlled adjunctive medication study, once determined to have capacity to consent to a clinical trial, retained appropriate study knowledge for at least 8 weeks. In the absence of a specific reason to suspect a loss of decisional capacity, there appears to be no need to routinely reevaluate participants during this type of clinical trial.

Reducing antipsychotic-induced weight gain in schizophrenia: a double-blind placebo-controlled study of reboxetine-betahistine combination

RATIONALE

Combination treatment with reboxetine, a selective norepinephrine reuptake inhibitor, and betahistine, a histamine H1 receptor agonist/H3 antagonist, was developed to produce complementary action in CNS pathways regulating appetite and body weight. In the present placebo-controlled study, we evaluated whether a reboxetine-betahistine combination attenuates olanzapine-induced weight gain in schizophrenia patients.

METHOD

Forty-three inpatients with DSM-IV schizophrenic disorder participated in a randomized double-blind study. Reboxetine (4 mg/day) with betahistine (48 mg/day) (N = 29) or placebo (N = 14) was co-administered with olanzapine (10 mg/day) for 6 weeks. Mental status was assessed at baseline and endpoint with relevant rating scales. Intention-to-treat method was used for statistical analysis.

RESULTS

Seven patients in the study group and four in the placebo group discontinued the trial. At the end of the trial, patients in the olanzapine/reboxetine + betahistine group gained significantly less weight than those in the olanzapine/placebo group [2.02 ± 2.37 and 4.77 ± 3.16 kg, respectively; t = 2. 89, degrees of freedom (df) = 41, p = 0.006]. The weight-attenuating effect of this combination was twofold larger than the weight-attenuating effect previously demonstrated with reboxetine alone. Significantly fewer patients in the study group than in the comparison group increased their initial weight by >7 %, the cutoff for clinically significant weight gain [3/29 (10.3 %) and 6/14 (42.9 %), respectively; χ (2) = 6.03, df = 1, p = 0.014]. The reboxetine-betahistine combination was safe and well tolerated.

CONCLUSIONS

Reboxetine-betahistine combination produces a clinically meaningful attenuation of olanzapine-induced weight gain. These results justify direct comparison between the reboxetine-betahistine combination and reboxetine alone.

Targeting presynaptic norepinephrine transporter in brown adipose tissue: a novel imaging approach and potential treatment for diabetes and obesity

Brown adipose tissue (BAT) plays a significant role in metabolism. In this study, we report the use of atomoxetine (a clinically applicable norepinephrine reuptake inhibitor) for (18)F-FDG PET imaging of BAT and its effects on heat production and blood glucose concentration. Fasted-male Sprague-Dawley rats were administered with intravenous (18)F-FDG. The same rats were treated with atomoxetine (0.1 mg/kg, i.v.) 30 min before (18)F-FDG administration. To confirm the β-adrenergic effects, propranolol (β-adrenergic inhibitor) 5 mg/kg was given intraperitoneally 30 min prior to atomoxetine administration. The effect of atomoxetine on BAT metabolism was assessed in fasted and non-fasted rats and on BAT temperature and blood glucose in fasted rats. In (18)F-FDG PET/CT images, interscapular BAT (IBAT) and other areas of BAT were clearly visualized. When rats were fasted, atomoxetine (0.1 mg/kg) increased the (18)F-FDG uptake of IBAT by factor of 24 within 30 min. Propranolol reduced the average (18)F-FDG uptake of IBAT significantly. Autoradiography of IBAT and white adipose tissue confirmed the data obtained by PET. When rats were not fasted, atomoxetine-induced increase of (18)F-FDG uptake in IBAT was delayed and occurred in 120 min. For comparison, direct stimulation of β(3)-adrenreceptors in non-fasted rats with CL-316, 243 occurred within 30 min. Atomoxetine-induced IBAT activation was associated with higher IBAT temperature and lower blood glucose. This was mediated by inhibition of norepinephrine reuptake transporters in IBAT leading to increased norepinephrine concentration in the synapse. Increased synaptic norepinephrine activates β(3)-adrenreceptors resulting in BAT hypermetabolism that is visible and quantifiable by (18)F-FDG PET/CT.

Interventions for the metabolic syndrome in schizophrenia: a review

The metabolic syndrome (MetS) is an increasingly prevalent condition in people with schizophrenia. It remains highly prevalent in the general population in developed countries, but recently health promotion campaigns and greater awareness of the high associated mortality rates have resulted in improvements in the rates of cardiovascular risk factors. This is not the case for people with schizophrenia who continue to have more than twice the rates of MetS and significantly higher mortality rates than the general population. Various behavioural and pharmacological interventions have been used to improve conditions that are linked to MetS, mainly smoking and obesity. This review aims to provide an update of the latest knowledge about the behavioural, pharmacological and other interventions that might help to combat this life-threatening problem in people with schizophrenia.

Systematic Review and Meta-analysis of Pharmacological Interventions for Weight Gain from Antipsychotics and Mood Stabilizers

Pharmacological treatments for serious mental illness (SMI) can cause weight gain and adverse metabolic effects. Many second generation antipsychotics and mood stabilizers appear to be particularly problematic in this regard. Several studies have investigated interventions for antipsychotic-induced, or less commonly mood stabilizer -induced, weight gain. Both lifestyle and pharmacological interventions have demonstrated effectiveness. We systematically review randomized controlled trials of pharmacological interventions for weight gain related to these medications. We conducted a meta-analysis of clinical trials for the most studied agents to estimate mean weight loss: metformin (2.93 kg, 95% C.I. 0.97-4.89, p=0.003), H(2) antagonists (1.78 kg (95% C.I. -0.50-4.06, p=0.13), topiramate (3.95 kg 95% C.I. 1.77-6.12, p=0.0004), and norepinephrine reuptake inhibitors (1.30 kg (95% C.I. -0.06-2.66, p=0.06). Among the studied options for antipsychotic-related weight gain, metformin has the strongest evidence base and may improve vascular risk factors beyond obesity. The use of topiramate is also supported by the literature and may improve psychotic symptoms in those refractory to treatment. A marginal benefit is seen with norepinephrine reuptake inhibitors, and any vascular benefits from such weight loss may be counteracted by increases in blood pressure or heart rate. Pharmacological therapies may offer benefits as a means of supplementing the effects of lifestyle changes for weight loss. However, the existing evidence provides little evidence of specificity for pharmacological therapies to antipsychotic-induced weight gain and has not studied any connection between benefits and reduced incidence of diabetes mellitus or any vascular outcomes.