Weight change on aripiprazole-clozapine combination in schizophrenic patients with weight gain and suboptimal response on clozapine: 16-week double-blind study

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.

Amisulpride augmentation in clozapine-unresponsive schizophrenia (AMICUS): a double-blind, placebo-controlled, randomised trial of clinical effectiveness and cost-effectiveness

BACKGROUND

When treatment-refractory schizophrenia shows an insufficient response to a trial of clozapine, clinicians commonly add a second antipsychotic, despite the lack of robust evidence to justify this practice.

OBJECTIVES

The main objectives of the study were to establish the clinical effectiveness and cost-effectiveness of augmentation of clozapine medication with a second antipsychotic, amisulpride, for the management of treatment-resistant schizophrenia.

DESIGN

The study was a multicentre, double-blind, individually randomised, placebo-controlled trial with follow-up at 12 weeks.

SETTINGS

The study was set in NHS multidisciplinary teams in adult psychiatry.

PARTICIPANTS

Eligible participants were people aged 18-65 years with treatment-resistant schizophrenia unresponsive, at a criterion level of persistent symptom severity and impaired social function, to an adequate trial of clozapine monotherapy.

INTERVENTIONS

Interventions comprised clozapine augmentation over 12 weeks with amisulpride or placebo. Participants received 400 mg of amisulpride or two matching placebo capsules for the first 4 weeks, after which there was a clinical option to titrate the dosage of amisulpride up to 800 mg or four matching placebo capsules for the remaining 8 weeks.

MAIN OUTCOME MEASURES

The primary outcome measure was the proportion of 'responders', using a criterion response threshold of a 20% reduction in total score on the Positive and Negative Syndrome Scale.

RESULTS

A total of 68 participants were randomised. Compared with the participants assigned to placebo, those receiving amisulpride had a greater chance of being a responder by the 12-week follow-up (odds ratio 1.17, 95% confidence interval 0.40 to 3.42) and a greater improvement in negative symptoms, although neither finding had been present at 6-week follow-up and neither was statistically significant. Amisulpride was associated with a greater side effect burden, including cardiac side effects. Economic analyses indicated that amisulpride augmentation has the potential to be cost-effective in the short term [net saving of between £329 and £2011; no difference in quality-adjusted life-years (QALYs)] and possibly in the longer term.

LIMITATIONS

The trial under-recruited and, therefore, the power of statistical analysis to detect significant differences between the active and placebo groups was limited. The economic analyses indicated high uncertainty because of the short duration and relatively small number of participants.

CONCLUSIONS

The risk-benefit of amisulpride augmentation of clozapine for schizophrenia that has shown an insufficient response to a trial of clozapine monotherapy is worthy of further investigation in larger studies. The size and extent of the side effect burden identified for the amisulpride-clozapine combination may partly reflect the comprehensive assessment of side effects in this study. The design of future trials of such a treatment strategy should take into account that a clinical response may be not be evident within the 4- to 6-week follow-up period usually considered adequate in studies of antipsychotic treatment of acute psychotic episodes. Economic evaluation indicated the need for larger, longer-term studies to address uncertainty about the extent of savings because of amisulpride and impact on QALYs. The extent and nature of the side effect burden identified for the amisulpride-clozapine combination has implications for the nature and frequency of safety and tolerability monitoring of clozapine augmentation with a second antipsychotic in both clinical and research settings.

TRIAL REGISTRATION

EudraCT number 2010-018963-40 and Current Controlled Trials ISRCTN68824876.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 49. See the NIHR Journals Library website for further project information.

Audit of combination and high-dose antipsychotic treatment in the community

Aims and method

To estimate the community prevalence of combination antipsychotic therapy and high-dose antipsychotic treatment via audit. Patients with an ICD-10 diagnosis of schizophrenia were identified through the NHS Greater Glasgow and Clyde Health Board patient information management system and their mental health records examined.

Results

In audit 1, 135 records were examined. The age range of patients was 24–74 years; 73% were male. Twelve per cent were on combined antipsychotic treatment and 3.7% required high-dose antipsychotics. Sixty-nine per cent of patients had documented in their record the reason for combined antipsychotic treatment compared with 40% on high-dose antipsychotics. In audit 2 (1 year later), 150 records were examined. Demographic details and prescription patterns remained similar to that of audit 1. However, 10% of patients received combined antipsychotic therapy and 2% remained on high-dose antipsychotics. Documented reasons for combination therapy increased to 87%, and to 67% for patients on high-dose antipsychotics.

Clinical implications

We need robust clinical trials, overcoming the problems of clinical effectiveness and clinical efficiency, to establish the merits of preferred antipsychotic combinations, as combination and high-dose antipsychotic treatments are unlikely to be eliminated in clinical practice in the foreseeable future.

Antipsychotic polypharmacy – confusion reigns

Polypharmacy is usually employed where single drugs are considered insufficiently effective. Some polypharmacy is rational and evidence based, some neither. Antipsychotic polypharmacy remains stubbornly widespread despite condemnation of the practice by numerous bodies. The practice could not be said to be evidence based. Its persistence probably stems from a well-meaning desire to improve response and from confusion about the mechanism of action of antipsychotics. In particular, the concept that more antipsychotic(s) must always be, or might be, ‘better’ is virtually groundless. Nonetheless, some specific antipsychotic polypharmacy regimens have shown particular benefits on adverse effect profiles. Targeted, evidence-based polypharmacy may be the way forward.

Antipsychotic combinations for schizophrenia

BACKGROUND

Many people with schizophrenia do not achieve a satisfactory treatment response with their initial antipsychotic drug treatment. Sometimes a second antipsychotic, in combination with the first, is used in these situations.

OBJECTIVES

To examine whether:1. treatment with antipsychotic combinations is effective for schizophrenia; and2. treatment with antipsychotic combinations is safe for the same illness.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's register which is based on regular searches of CINAHL, BIOSIS, AMED, Embase, PubMed, MEDLINE, PsycINFO, and registries of clinical trials. There are no language, time, document type, or publication status limitations for inclusion of records in the register. We ran searches in September 2010, August 2012 and January 2016. We checked for additional trials in the reference lists of included trials.

SELECTION CRITERIA

We included all randomised and quasi-randomised controlled trials comparing antipsychotic combinations with antipsychotic monotherapy for the treatment of schizophrenia and/or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

We independently extracted data from the included studies. We analysed dichotomous data using risk ratios (RR) and the 95% confidence intervals (CI). We analysed continuous data using mean difference (MD) with a 95% CIs. For the meta-analysis we used a random-effects model. We used GRADE to complete a 'Summary of findings' table and assessed risk of bias for included studies.

MAIN RESULTS

Sixty-two studies are included in the review, 31 of these compared clozapine monotherapy with clozapine combination. We considered the risk of bias in the included studies to be moderate to high. The majority of trials had unclear allocation concealment, method of randomisation and blinding, and were not free of selective reporting.There is some limited evidence that combination therapy is superior to monotherapy in improving clinical response (RR 0.73, 95% CI 0.63 to 0.85; participants = 2364; studies = 29, very low-quality evidence), although subgroup analyses show that the positive result was due to the studies with clozapine in both the monotherapy and combination groups (RR 0.66, 95% CI 0.53 to 0.83; participants = 1127; studies = 17). Few studies reported on rate of relapse, most likely due to the short length of the studies. Overall, a combination of antipsychotics was not superior or inferior to antipsychotic monotherapy in preventing relapse (RR 0.63, 95% CI 0.31 to 1.29; participants = 512; studies = 3, very low-quality evidence), but the pooled data showed high heterogeneity (I² = 82%). A combination of antipsychotics was not superior or inferior to antipsychotic monotherapy in reducing the number of participants discontinuing treatment early (RR 0.89, 95% CI 0.73 to 1.07; participants = 3103; studies = 43, low-quality evidence). No difference was found between treatment groups in the number of participants hospitalised (RR 0.96, 95% CI 0.36 to 2.55; participants = 202; studies = 3, low-quality evidence) . We did not find evidence of a difference between treatment groups in serious adverse events or those requiring discontinuation (RR 1.05, 95% CI 0.65 to 1.69; participants = 2398; studies = 30, very low-quality evidence). There is as lack of evidence on clinically important change in quality of life, with only four studies reporting average endpoint or change data for this outcome on three different scales, none of which showed a difference between treatment groups.

AUTHORS' CONCLUSIONS

Currently, most evidence regarding the use of antipsychotic combinations comes from short-term trials, limiting the assessment of long-term efficacy and safety. We found very low-quality evidence that a combination of antipsychotics may improve the clinical response. We also found low-quality evidence that a combination of antipsychotics is may make no difference at preventing participants from leaving the study early, preventing relapse and/or causing more serious adverse events than monotherapy.

Clozapine combined with different antipsychotic drugs for treatment-resistant schizophrenia

BACKGROUND

Between 40% and 70% of people with treatment-resistant schizophrenia do not respond to clozapine, despite adequate blood levels. For these people, a number of treatment strategies have emerged, including the prescription of a second anti-psychotic drug in combination with clozapine.

OBJECTIVES

To determine the clinical effects of various clozapine combination strategies with antipsychotic drugs in people with treatment-resistant schizophrenia both in terms of efficacy and tolerability.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials (to 28 August 2015) and MEDLINE (November 2008). We checked the reference lists of all identified randomised controlled trials (RCT). For the first version of the review, we also contacted pharmaceutical companies to identify further trials.

SELECTION CRITERIA

We included only RCTs recruiting people of both sexes, aged 18 years or more, with a diagnosis of treatment-resistant schizophrenia (or related disorders) and comparing clozapine plus another antipsychotic drug with clozapine plus a different antipsychotic drug.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data, we calculated risk ratios (RRs) and 95% confidence intervals (CI) on an intention-to-treat basis using a random-effects meta-analysis. For continuous data, we calculated mean differences (MD) and 95% CIs. We used GRADE to create 'Summary of findings' tables and assessed risk of bias for included studies.

MAIN RESULTS

We identified two further studies with 169 participants that met our inclusion criteria. This review now includes five studies with 309 participants. The quality of evidence was low, and, due to the high degree of heterogeneity between studies, we were unable to undertake a formal meta-analysis to increase the statistical power.For this update, we specified seven main outcomes of interest: clinical response in mental state (clinically significant response, mean score/change in mental state), clinical response in global state (mean score/change in global state), weight gain, leaving the study early (acceptability of treatment), service utilisation outcomes (hospital days or admissions to hospital) and quality of life.We found some significant differences between clozapine combination strategies for global and mental state (clinically significant response and change), and there were data for leaving the study early and weight gain. We found no data for service utilisation and quality of life. Clozapine plus aripiprazole versus clozapine plus haloperidolThere was no long-term significant difference between aripiprazole and haloperidol combination strategies in change of mental state (1 RCT, n = 105, MD 0.90, 95% CI -4.38 to 6.18, low quality evidence). There were no adverse effect data for weight gain but there was a benefit of aripiprazole for adverse effects measured by the LUNSERS at 12 weeks (1 RCT, n = 105, MD -4.90, 95% CI -8.48 to -1.32) and 24 weeks (1 RCT, n = 105, MD -4.90, 95% CI -8.25 to -1.55), but not 52 weeks (1 RCT, n = 105, MD -4.80, 95% CI -9.79 to 0.19). Similar numbers of participants from each group left the study early (1 RCT, n = 106, RR 1.27, 95% CI 0.72 to 2.22, very low quality evidence). Clozapine plus amisulpride versus clozapine plus quetiapine One study showed a significant benefit of amisulpride over quetiapine in the short term, for both change in global state (Clinical Global Impression (CGI): 1 RCT, n = 50, MD -0.90, 95% CI -1.38 to -0.42, very low quality evidence) and mental state (Brief Psychiatric Rating Scale (BPRS): 1 RCT, n = 50, MD -4.00, 95% CI -5.86 to -2.14, low quality evidence). Similar numbers of participants from each group left the study early (1 RCT, n = 56, RR 0.20, 95% CI 0.02 to 1.60, very low quality evidence) Clozapine plus risperidone versus clozapine plus sulpirideThere was no difference between risperidone and sulpiride for clinically significant response, defined by the study as 20% to 50% reduction in Positive and Negative Syndrome Scale (PANSS) (1 RCT, n = 60, RR 0.82, 95% CI 0.40 to 1.68, very low quality evidence). There were similar equivocal results for weight gain (1 RCT, n = 60, RR 0.40, 95% CI 0.08 to 1.90, very low quality evidence) and mental state (PANSS total: 1 RCT, n = 60, MD -2.28, 95% CI -7.41 to 2.85, very low quality evidence). No-one left the study early. Clozapine plus risperidone versus clozapine plus ziprasidoneThere was no difference between risperidone and ziprasidone for clinically significant response (1 RCT, n = 24, RR 0.80, 95% CI 0.28 to 2.27, very low quality evidence), change in global state CGI-II score (1 RCT, n = 22, MD -0.30, 95% CI -0.82 to 0.22, very low quality evidence), change in PANSS total score (1 RCT, n = 16, MD 1.00, 95% CI -7.91 to 9.91, very low quality evidence) or leaving the study early (1 RCT, n = 24, RR 1.60, 95% CI 0.73 to 3.49, very low quality evidence). Clozapine plus ziprasidone versus clozapine plus quetiapineOne study found, in the medium term, a superior effect for ziprasidone combination compared with quetiapine combination for clinically significant response in mental state (> 50% reduction PANSS: 1 RCT, n = 63, RR 0.54, 95% CI 0.35 to 0.81, low quality evidence), global state (CGI - Severity score: 1 RCT, n = 60, MD -0.70, 95% CI -1.18 to -0.22, low quality evidence) and mental state (PANSS total score: 1 RCT, n = 60, MD -12.30, 95% CI -22.43 to -2.17, low quality evidence). There was no effect for leaving the study early (1 RCT, n = 63, RR 0.52, CI 0.05 to 5.41, very low quality evidence).

AUTHORS' CONCLUSIONS

The reliability of results from this review is limited, evidence is of low or very low quality. Furthermore, due to the limited number of included studies, we were unable to undertake formal meta-analyses. As a consequence, any conclusions drawn from these findings are based on single, small-sized RCTs with high risk of type II error. Properly conducted and adequately powered RCTs are required. Future trialists should seek to measure patient-important outcomes such as quality of life, as well as clinical response and adverse effects.

Quality of prescribing for schizophrenia: evidence from a national audit in England and Wales

The National Audit of Schizophrenia (NAS) examined the quality of care received in England and Wales. Part of the audit set out to determine whether six prescribing standards, set by the national clinical guidelines for schizophrenia, were being implemented and to prompt improvements in care. Mental Health Trusts and Health Boards provided data obtained from case-notes for adult patients living in the community with schizophrenia or schizoaffective disorder. An audit of practice tool was developed for data collection. Most of the 5055 patients reviewed were receiving pharmacological treatment according to national guidelines. However, 15.9% of the total sample (95%CI: 14.9-16.9) were prescribed two or more antipsychotics concurrently and 10.1% of patients (95%CI: 9.3-10.9) were prescribed medication in excess of recommended limits. Overall 23.7% (95%CI: 22.5-24.8) of patients were receiving clozapine. However, there were many with treatment resistance who had no clear reason documented as to why they had not had a trial of clozapine (430/1073, 40.1%). In conclusion, whilst most people were prescribed medication in accordance with nationally agreed standards, there was considerable variation between service providers. Antipsychotic polypharmacy, high dose prescribing and clozapine underutilisation in treatment resistance were all key concerns which need to be further addressed.

Antipsychotic polypharmacy in psychotic disorders: a critical review of neurobiology, efficacy, tolerability and cost effectiveness

OBJECTIVE

The purpose of this study was to review the scientific evidence for neurobiological rationale, efficacy, tolerability and cost effectiveness of antipsychotic polypharmacy (APP).

DATA SOURCES

A systematic literature search of Medline, Embase, Ovid and the Cochrane Database of Systematic Reviews until April 2012 was carried out.

RESULTS

Theories behind APP have only modest pre-clinical and clinical evidence. We found limited statistical evidence supporting modest efficacy of APP in patients with psychotic symptoms refractory to clozapine. APP is associated with increased mortality, metabolic syndrome, decreased cognitive functioning, high dose prescription and non-adherence. It brings up extra costs, lacking evidence for cost-effectiveness.

CONCLUSIONS

Pre-clinical studies underpinning neurobiological hypotheses in APP are lacking. Evidence supporting efficacy of APP is limited with modest beneficial clinical relevance. APP is associated with several serious adverse effects and increased health costs. In the absence of more convincing pre-clinical support and clinical evidence we advise adherence to existing guidelines and limiting combinations of antipsychotics (in consideration with other pharmacotherapeutic, somatic and psychotherapeutic options) to patients with clozapine-refractory psychosis in well-evaluated individual trials that might need 10 weeks or more.

Augmentation of clozapine with a second antipsychotic - a meta-analysis

OBJECTIVE

To examine using meta-analysis the effect of adding a second antipsychotic to established clozapine monotherapy.

METHOD

A literature search was conducted in April 2011, and randomised placebo-controlled double-blind studies were identified. We performed a meta-analysis of efficacy (as standardised mean difference) and tolerability (withdrawals from trials) and a regression analysis of duration of study versus effect size. We also examined publication bias using funnel-plot analysis.

RESULTS

Overall, 14 studies were included (734 subjects). Individual study numbers ranged from 10 to 207 (mean 52.6, median 40). Augmentation of clozapine with a second antipsychotic conferred a small benefit over placebo (effect size -0.239 (95% CI: -0.452, -0.026); P = 0.028). Meta-regression of the effect of length of treatment on effect size showed no relationship (P = 0.254). The risk of discontinuing antipsychotic augmentation was no greater than the risk of discontinuing placebo (RR = 1.20, 95% CI 0.80-1.82). There was no evidence of publication bias.

CONCLUSION

Augmentation with a second antipsychotic is modestly beneficial in patients not responding fully to clozapine. Tolerability seems not to be adversely affected, at least in the short term. Longer studies do not appear to increase the probability of showing positive effects for augmentation.

Evidence-based pharmacotherapy of schizophrenia

We describe the pharmacological treatment of schizophrenia and have arranged the manuscript as a simple algorithm which starts from the choice of an antipsychotic drug for an acutely ill patient and concludes with the most important questions about maintenance treatment. In acutely ill patients the choice of drug is mainly based on pragmatic criteria. Among many strategies used for agitated patients, haloperidol plus promethazine is the best examined one. In case of persistent depression or negative symptoms treatment includes antidepressants, and some second-generation antipsychotic drugs (SGAs) have been found somewhat superior to first-generation antipsychotic drugs (FGAs) in these domains. If an antipsychotic is suspected to be ineffective, several factors need to be checked before action is taken. Few trials have addressed strategies such as switching the drug or increasing the dose in case of non-response. Clozapine remains the gold-standard for treatment-refractory patients, while none of the numerous augmentation strategies that have been examined by randomized controlled trials can be generally recommended. Maintenance treatment with antipsychotic drugs effectively reduces relapse rates. Small, not definitive, studies have shown that withdrawing antipsychotics from patients who have been stable for up to 6 yr leads to more relapses than continuing medication. In effect, continuous treatment is more effective than intermittent strategies. The identification of optimum doses for relapse prevention with FGAs has proven difficult, and there is little randomized data on SGAs. Although the randomized evidence on a superiority of depot compared to oral treatment is not ideal, this approach suggests obvious advantages in assuring compliance.

[Polypharmacy in schizophrenia]

BACKGROUND

While most guidelines recommend monotherapy with second-generation antipsychotics (SGA) in schizophrenia, the combined application of multiple psychotropic agents is very common, especially in treatment-refractory cases.

METHODS

This review summarizes the evidence of combined antipsychotic treatment strategies and the augmentation of antipsychotics with mood stabilizers, antidepressants and experimental substances, based on publications accessible in public databases (Medline/Ovid, Google, http://www.clinicaltrials.gov) up to October 2009.

RESULTS

Polypharmacy aims to address several aspects of treatment resistance and side effects of antipsychotics. Some evidence supports the augmentation of antipsychotics with antidepressants for negative symptoms and comorbid major depressive episodes. The add-on of lithium and mood stabilizers lacks compelling evidence but might be beneficial for specific subgroups. For treatment-resistant cognitive symptoms, cognitive re-mediation seems most promising as no pharmacological add-on strategy has gained convincing evidence so far. Acute dystonic movements should be treated with anticholinergic agents while agitation and anxiety might respond to short-term application of benzodiazepines. Treatment-resistant positive and/or negative symptoms should primarily lead to clozapine monotherapy; the add-on of a second SGA may be considered in single cases.

CONCLUSIONS

In general, rigorous data on combination therapy in schizophrenia are rare, and further randomized controlled trials (RCT), naturalistic and head-to-head-studies are necessary.

Antipsychotic switching for people with schizophrenia who have neuroleptic-induced weight or metabolic problems

BACKGROUND

Weight gain is common for people with schizophrenia and this has serious implications for a patient's health and well being. Switching strategies have been recommended as a management option.

OBJECTIVES

To determine the effects of antipsychotic medication switching as a strategy for reducing or preventing weight gain and metabolic problems in people with schizophrenia.

SEARCH STRATEGY

We searched key databases and the Cochrane Schizophrenia Group's trials register (January 2005 and June 2007), reference sections within relevant papers and contacted the first author of each relevant study and other experts to collect further information.

SELECTION CRITERIA

All clinical randomised controlled trials comparing switching of antipsychotic medication as an intervention for antipsychotic induced weight gain and metabolic problems with continuation of medication and/or other weight loss treatments (pharmacological and non pharmacological) in people with schizophrenia or schizophrenia-like illnesses.

DATA COLLECTION AND ANALYSIS

Studies were reliably selected, quality assessed and data extracted. For dichotomous data we calculated risk ratio (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis, based on a fixed-effect model. The primary outcome measures were weight loss, metabolic syndrome, relapse and general mental state.

MAIN RESULTS

We included four studies for the review with a total of 636 participants. All except one study had a duration of 26 weeks or less. There was a mean weight loss of 1.94 kg (2 RCT, n = 287, CI -3.9 to 0.08) when switched to aripiprazole or quetiapine from olanzapine. BMI also decreased when switched to quetiapine (1 RCT, n = 129, MD -0.52 CI -1.26 to 0.22) and aripiprazole (1 RCT, n = 173, RR 0.28 CI 0.13 to 0.57) from olanzapine.Fasting blood glucose showed a significant decrease when switched to aripiprazole or quetiapine from olanzapine. (2 RCT, MD -2.53 n = 280 CI -2.94 to -2.11). One RCT also showed a favourable lipid profile when switched to aripiprazole but these measures were reported as percentage changes, rather than means with standard deviation.People are less likely to leave the study early if they remain on olanzapine compared to switching to quetiapine or aripiprazole.There was no significant difference in outcomes of mental state, global state, and adverse events between groups which switched medications and those that remained on previous medication. Three different switching strategies were compared and no strategy was found to be superior to the others for outcomes of weight gain, mental state and global state.

AUTHORS' CONCLUSIONS

Evidence from this review suggests that switching antipsychotic medication to one with lesser potential for causing weight gain or metabolic problems could be an effective way to manage these side effects, but the data were weak due to the limited number of trials in this area and small sample sizes. Poor reporting of data also hindered using some trials and outcomes. There was no difference in mental state, global state and other treatment related adverse events between switching to another medication and continuing on the previous one. When the three switching strategies were compared none of them had an advantage over the others in their effects on the primary outcomes considered in this review. Better designed trials with adequate power would provide more convincing evidence for using medication switching as an intervention strategy.

Polypharmacy in schizophrenia

PURPOSE OF REVIEW

Although most guidelines recommend monotherapy in schizophrenia, the combined application of multiple psychotropic agents is very common, especially in treatment-refractory cases. We review the empirical basis supporting these attempts and their relevance for clinical practice.

RECENT FINDINGS

Polypharmacy intends to address different aspects of treatment resistance, most importantly insufficient response of psychotic positive and negative symptoms, but also cognitive disturbances, affective comorbidity, obsessive-compulsive syndromes and side-effects of antipsychotic drugs. This review summarizes the current state of evidence of combined antipsychotic treatment strategies and the augmentation of antipsychotics with mood stabilizers, antidepressants and experimental substances.

SUMMARY

In general, rigorous data on combination therapy in schizophrenia are rare and further randomized controlled trials, naturalistic trials and head-to-head-trials are necessary. Some evidence supports a combination of antipsychotics and antidepressants for negative symptoms and comorbid major depressive episodes. The add-on of lithium and mood stabilizers lacks compelling evidence, but might be beneficial for specific subgroups. For treatment-resistant cognitive symptoms, antipsychotic medication should be combined with cognitive remediation, as no pharmacological add-on strategy has gained convincing evidence so far. Treatment-emergent positive and/or negative symptoms under clozapine monotherapy might benefit from adding a second atypical substance.

Advantages and disadvantages of combination treatment with antipsychotics ECNP Consensus Meeting, March 2008, Nice

TERMINOLOGY AND PRINCIPLES OF COMBINING ANTIPSYCHOTICS WITH A SECOND MEDICATION: The term "combination" includes virtually all the ways in which one medication may be added to another. The other commonly used terms are "augmentation" which implies an additive effect from adding a second medicine to that obtained from prescribing a first, an "add on" which implies adding on to existing, possibly effective treatment which, for one reason or another, cannot or should not be stopped. The issues that arise in all potential indications are: a) how long it is reasonable to wait to prove insufficiency of response to monotherapy; b) by what criteria that response should be defined; c) how optimal is the dose of the first monotherapy and, therefore, how confident can one be that its lack of effect is due to a truly inadequate response? Before one considers combination treatment, one or more of the following criteria should be met; a) monotherapy has been only partially effective on core symptoms; b) monotherapy has been effective on some concurrent symptoms but not others, for which a further medicine is believed to be required; c) a particular combination might be indicated de novo in some indications; d) The combination could improve tolerability because two compounds may be employed below their individual dose thresholds for side effects. Regulators have been concerned primarily with a and, in principle at least, c above. In clinical practice, the use of combination treatment reflects the often unsatisfactory outcome of treatment with single agents. ANTIPSYCHOTICS IN MANIA: There is good evidence that most antipsychotics tested show efficacy in acute mania when added to lithium or valproate for patients showing no or a partial response to lithium or valproate alone. Conventional 2-armed trial designs could benefit from a third antipsychotic monotherapy arm. In the long term treatment of bipolar disorder, in patients responding acutely to the addition of quetiapine to lithium or valproate, this combination reduces the subsequent risk of relapse to depression, mania or mixed states compared to monotherapy with lithium or valproate. Comparable data is not available for combination with other antipsychotics. ANTIPSYCHOTICS IN MAJOR DEPRESSION: Some atypical antipsychotics have been shown to induce remission when added to an antidepressant (usually a SSRI or SNRI) in unipolar patients in a major depressive episode unresponsive to the antidepressant monotherapy. Refractoriness is defined as at least 6 weeks without meeting an adequate pre-defined treatment response. Long term data is not yet available to support continuing efficacy. SCHIZOPHRENIA: There is only limited evidence to support the combination of two or more antipsychotics in schizophrenia. Any monotherapy should be given at the maximal tolerated dose and at least two antipsychotics of different action/tolerability and clozapine should be given as a monotherapy before a combination is considered. The addition of a high potency D2/3 antagonist to a low potency antagonist like clozapine or quetiapine is the logical combination to treat positive symptoms, although further evidence from well conducted clinical trials is needed. Other mechanisms of action than D2/3 blockade, and hence other combinations might be more relevant for negative, cognitive or affective symptoms. OBSESSIVE-COMPULSIVE DISORDER: SSRI monotherapy has moderate overall average benefit in OCD and can take as long as 3 months for benefit to be decided. Antipsychotic addition may be considered in OCD with tic disorder and in refractory OCD. For OCD with poor insight (OCD with "psychotic features"), treatment of choice should be medium to high dose of SSRI, and only in refractory cases, augmentation with antipsychotics might be considered. Augmentation with haloperidol and risperidone was found to be effective (symptom reduction of more than 35%) for patients with tics. For refractory OCD, there is data suggesting a specific role for haloperidol and risperidone as well, and some data with regard to potential therapeutic benefit with olanzapine and quetiapine. ANTIPSYCHOTICS AND ADVERSE EFFECTS IN SEVERE MENTAL ILLNESS: Cardio-metabolic risk in patients with severe mental illness and especially when treated with antipsychotic agents are now much better recognized and efforts to ensure improved physical health screening and prevention are becoming established.

Augmentation of clozapine with a second antipsychotic--a meta-analysis of randomized, placebo-controlled studies

OBJECTIVE

Inadequate response to clozapine treatment is frequently encountered in practice and augmentation strategies have been developed in an attempt to improve response. Aims of the study were to evaluate the therapeutic effect of adding an antipsychotic drug to clozapine treatment.

METHOD

Meta-analysis of randomized, placebo-controlled studies of antipsychotic augmentation of clozapine treatment.

RESULTS

Ten studies (including 522 subjects) met inclusion criteria. Antipsychotic augmentation showed significant benefit over the addition of placebo on only one outcome measure examined [mean effect size for rating scale score (BPRS/PANSS) -0.180, 95% CI -0.356 to -0.004]. Antipsychotic augmentation showed no advantage on withdrawals from trials (risk ratio 1.261, 95% CI 0.679-2.345) or on CGI scores (effect size -0.661, 95% CI -1.475 to 0.151). Duration of study was not associated with outcome (P = 0.95). There was no evidence of publication bias.

CONCLUSION

In studies lasting up to 16 weeks, the addition of an antipsychotic to clozapine treatment has marginal therapeutic benefit. Longer and larger trials are necessary to demonstrate the precise therapeutic utility of antipsychotic co-therapy with clozapine.