Cessation of medication for people with schizophrenia already stable on chlorpromazine

Maintenance treatment with antipsychotic drugs for schizophrenia

BACKGROUND

The symptoms and signs of schizophrenia have been linked to high levels of dopamine in specific areas of the brain (limbic system). Antipsychotic drugs block the transmission of dopamine in the brain and reduce the acute symptoms of the disorder. An original version of the current review, published in 2012, examined whether antipsychotic drugs are also effective for relapse prevention. This is the updated version of the aforesaid review.

OBJECTIVES

To review the effects of maintaining antipsychotic drugs for people with schizophrenia compared to withdrawing these agents.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials including the registries of clinical trials (12 November 2008, 10 October 2017, 3 July 2018, 11 September 2019).

SELECTION CRITERIA

We included all randomised trials comparing maintenance treatment with antipsychotic drugs and placebo for people with schizophrenia or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CIs) on an intention-to-treat basis based on a random-effects model. For continuous data, we calculated mean differences (MD) or standardised mean differences (SMD), again based on a random-effects model.

MAIN RESULTS

The review currently includes 75 randomised controlled trials (RCTs) involving 9145 participants comparing antipsychotic medication with placebo. The trials were published from 1959 to 2017 and their size ranged between 14 and 420 participants. In many studies the methods of randomisation, allocation and blinding were poorly reported. However, restricting the analysis to studies at low risk of bias gave similar results. Although this and other potential sources of bias limited the overall quality, the efficacy of antipsychotic drugs for maintenance treatment in schizophrenia was clear. Antipsychotic drugs were more effective than placebo in preventing relapse at seven to 12 months (primary outcome; drug 24% versus placebo 61%, 30 RCTs, n = 4249, RR 0.38, 95% CI 0.32 to 0.45, number needed to treat for an additional beneficial outcome (NNTB) 3, 95% CI 2 to 3; high-certainty evidence). Hospitalisation was also reduced, however, the baseline risk was lower (drug 7% versus placebo 18%, 21 RCTs, n = 3558, RR 0.43, 95% CI 0.32 to 0.57, NNTB 8, 95% CI 6 to 14; high-certainty evidence). More participants in the placebo group than in the antipsychotic drug group left the studies early due to any reason (at seven to 12 months: drug 36% versus placebo 62%, 24 RCTs, n = 3951, RR 0.56, 95% CI 0.48 to 0.65, NNTB 4, 95% CI 3 to 5; high-certainty evidence) and due to inefficacy of treatment (at seven to 12 months: drug 18% versus placebo 46%, 24 RCTs, n = 3951, RR 0.37, 95% CI 0.31 to 0.44, NNTB 3, 95% CI 3 to 4). Quality of life might be better in drug-treated participants (7 RCTs, n = 1573 SMD -0.32, 95% CI to -0.57 to -0.07; low-certainty evidence); probably the same for social functioning (15 RCTs, n = 3588, SMD -0.43, 95% CI -0.53 to -0.34; moderate-certainty evidence). Underpowered data revealed no evidence of a difference between groups for the outcome 'Death due to suicide' (drug 0.04% versus placebo 0.1%, 19 RCTs, n = 4634, RR 0.60, 95% CI 0.12 to 2.97,low-certainty evidence) and for the number of participants in employment (at 9 to 15 months, drug 39% versus placebo 34%, 3 RCTs, n = 593, RR 1.08, 95% CI 0.82 to 1.41, low certainty evidence). Antipsychotic drugs (as a group and irrespective of duration) were associated with more participants experiencing movement disorders (e.g. at least one movement disorder: drug 14% versus placebo 8%, 29 RCTs, n = 5276, RR 1.52, 95% CI 1.25 to 1.85, number needed to treat for an additional harmful outcome (NNTH) 20, 95% CI 14 to 50), sedation (drug 8% versus placebo 5%, 18 RCTs, n = 4078, RR 1.52, 95% CI 1.24 to 1.86, NNTH 50, 95% CI not significant), and weight gain (drug 9% versus placebo 6%, 19 RCTs, n = 4767, RR 1.69, 95% CI 1.21 to 2.35, NNTH 25, 95% CI 20 to 50).

AUTHORS' CONCLUSIONS

For people with schizophrenia, the evidence suggests that maintenance on antipsychotic drugs prevents relapse to a much greater extent than placebo for approximately up to two years of follow-up. This effect must be weighed against the adverse effects of antipsychotic drugs. Future studies should better clarify the long-term morbidity and mortality associated with these drugs.

Haloperidol discontinuation for people with schizophrenia

BACKGROUND

Schizophrenia is a disabling serious mental illness that can be chronic. Haloperidol, one of the first generation of antipsychotic drugs, is effective in the treatment of schizophrenia but can have adverse side effects. The effects of stopping haloperidol in people with schizophrenia who are stable on their prescription are not well researched in the context of systematic reviews.

OBJECTIVES

To review the effects of haloperidol discontinuation in people with schizophrenia who are stable on haloperidol.

SEARCH METHODS

On 20 February 2015, 24 May 2017, and 12 January 2019, we searched the Cochrane Schizophrenia Group's Study-Based Register of Trials including trial registers.

SELECTION CRITERIA

We included clinical trials randomising adults with schizophrenia or related disorders who were receiving haloperidol, and were stable. We included trials that randomised such participants to either continue their current treatment with haloperidol or discontinue their haloperidol treatment. We included trials that met our selection criteria and reported usable data.

DATA COLLECTION AND ANALYSIS

We independently checked all records retrieved from the search and obtained full reports of relevant records for closer inspection. We extracted data from included studies independently. All usable data were dichotomous, and we calculated relative risks (RR) and their 95% confidence intervals (95% CI) using a fixed-effect model. We assessed risk of bias within the included studies and used GRADE to create a 'Summary of findings' table.

MAIN RESULTS

We included five randomised controlled trials (RCTs) with 232 participants comparing haloperidol discontinuation with haloperidol continuation. Discontinuation was achieved in all five studies by replacing haloperidol with placebo. The trials' size ranged between 23 and 87 participants. The methods of randomisation, allocation concealment and blinding were poorly reported.Participants allocated to discontinuing haloperidol treatment were more likely to show no improvement in global state compared with those in the haloperidol continuation group (n = 49; 1 RCT; RR 2.06, 95% CI 1.33 to 3.20; very low quality evidence: our confidence in the effect estimate is limited due to relevant methodological shortcomings of included trials). Those who continued haloperidol treatment were less likely to experience a relapse compared to people who discontinued taking haloperidol (n = 165; 4 RCTs; RR 1.80, 95% CI 1.18 to 2.74; very low quality evidence). Satisfaction with treatment (measured as numbers leaving the study early) was similar between groups (n = 43; 1 RCT; RR 0.13, 95% CI 0.01 to 2.28; very low quality evidence).No usable mental state, general functioning, general behaviour or adverse effect data were reported by any of the trials.

AUTHORS' CONCLUSIONS

This review provides limited evidence derived from small, short-term studies. The longest study was for one year, making it difficult to generalise the results to a life-long disorder. Very low quality evidence shows that discontinuation of haloperidol is associated with an increased risk of relapse and a reduction in the risk of 'global state improvement'. However, participant satisfaction with haloperidol treatment was not different from participant satisfaction with haloperidol discontinuation as measured by leaving the studies early. Due to the very low quality of these results, firm conclusions cannot be made. In addition, the available studies did not report usable data regarding the adverse effects of haloperidol treatment.Considering that haloperidol is one of the most widely used antipsychotic drugs, it was surprising that only a small number of studies into the benefit and harm of haloperidol discontinuation were available. Moreover, the available studies did not report on outcomes that are important to clinicians and to people with schizophrenia, particularly adverse effects and social outcomes. Better designed trials are warranted.

Chlorpromazine versus piperacetazine for schizophrenia

BACKGROUND

Schizophrenia is a severe mental disorder with a prevalence of about 1% among the general population. It is listed among the top 10 causes of disability-adjusted life years (DALYs) worldwide. Antipsychotics are the mainstay treatment. Piperacetazine has been reported to be as clinically effective as chlorpromazine, a well established 'benchmark' antipsychotic, for people with schizophrenia. However, the side effect profiles of these antipsychotics differ and it is important that an evidence base is available comparing the benefits, and potential harms of these two antipsychotics.

OBJECTIVES

To assess the clinical and side effects of chlorpromazine for people with schizophrenia and schizophrenia-like psychoses in comparison with piperacetazine.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Trials Register (6 June 2015 and 8 October 2018) which is based on regular searches of CINAHL, CENTRAL, BIOSIS, AMED, Embase, PubMed, MEDLINE, PsycINFO and registries of clinical trials. There are no language, date, document type, or publication status limitations for inclusion of records in the register.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) focusing on chlorpromazine versus piperacetazine for people with schizophrenia, reporting useable data.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For binary outcomes, we calculated risk ratio (RR) and its 95% confidence interval (CI), on an intention-to-treat basis. For continuous data, we estimated the mean difference (MD) between groups and its 95% CI. We employed a fixed-effect model for analyses. We assessed risk of bias for included studies and created 'Summary of findings' tables using GRADE.

MAIN RESULTS

We found 12 records referring to six trials. We included five trials, all from the 1970s, randomising 343 participants. We excluded one trial. The overall methodology and data reporting by the trials was poor. Only short-term data were available.Results from the included trials found that, in terms of global state improvement, when rated by a psychiatrist, there was no clear difference between chlorpromazine and piperacetazine (RR 0.90, 95% CI 0.80 to 1.02; participants = 208; studies = 2; very low-quality evidence). One trial reported change scores on the mental state scale Brief Psychiatric Rating Scale (BPRS); no clear difference was observed (MD -0.40, 95% CI -1.41 to 0.61; participants = 182; studies = 1; very low-quality evidence). Chlorpromazine appears no worse or better than piperacetazine regarding adverse effects. In both treatment groups, around 60% of participants experienced some sort of adverse effect (RR 1.00, 95% CI 0.75 to 1.33; participants = 74; studies = 3; very low-quality evidence), with approximately 40% of these participants experiencing some parkinsonism-type movement disorder (RR 0.95, CI 0.61 to 1.49; participants = 106; studies = 3; very low-quality evidence). No clear difference in numbers of participants leaving the study early for any reason was observed (RR 0.50, 95% CI 0.10 to 2.56; participants = 256; studies = 4; very low-quality evidence). No trial reported data for change in negative symptoms or economic costs.

AUTHORS' CONCLUSIONS

The results of this review show chlorpromazine and piperacetazine may have similar clinical efficacy, but data are based on very small numbers of participants and the evidence is very low quality. We can not make firm conclusions based on such data. Currently, should clinicians and people with schizophrenia need to choose between chlorpromazine and piperacetazine they should be aware there is no good quality evidence to base decisions. More high quality research is needed.

Chlorpromazine versus penfluridol for schizophrenia

BACKGROUND

The efficacy of chlorpromazine, a benchmark antipsychotic, has not been fully assessed in direct comparison with different individual antipsychotics. Penfluridol is another old antipsychotic with a long half-life so one oral dose may last up to one week. This could confer advantage.

OBJECTIVES

To assess the clinical effects of chlorpromazine compared with penfluridol for adults with schizophrenia.

SEARCH METHODS

On 31 March 2017, we searched the Cochrane Schizophrenia Group's Study-Based Register of Trials which is based on regular searches of CINAHL, BIOSIS, AMED, Embase, PubMed, MEDLINE, PsycINFO, and registries of clinical trials. There are no language, date, document type, or publication status limitations for inclusion of records in the register.

SELECTION CRITERIA

We included all randomised clinical trials focusing on chlorpromazine versus penfluridol for adults with schizophrenia or related disorders. Outcomes of interest were death, service utilisation, global state, mental state, adverse effects and leaving the study early. We included trials meeting our selection criteria and reporting useable data.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For binary outcomes, we calculated risk ratio (RR) and its 95% confidence interval (CI), on an intention-to-treat basis. For continuous data, we planned to estimate the mean difference (MD) between groups and its 95% CI. We employed a fixed-effect model for analyses. We assessed risk of bias for included studies and created a 'Summary of findings' table using GRADE.

MAIN RESULTS

The review includes three studies with a total of 130 participants. Short-term results for hospital admissions showed no clear difference between chlorpromazine and penfluridol (1 RCT, n = 29, RR 0.19, 95% CI 0.01 to 3.60, low-quality evidence). No clear difference in the incidence of akathisia was found at medium term (2 RCTs, n = 85, RR 0.19, 95% CI 0.04 to 1.06, low-quality evidence), and similar numbers of participants - nearly half - from each treatment group left the study early (3 RCTs, n = 130, RR 1.21, 95% CI 0.83 to 1.77, low-quality evidence). The risk of needing additional antiparkinsonian medication was less in the chlorpromazine group (2 RCTs, n = 74, RR 0.70, 95% CI 0.51 to 0.95). No useable data reported clinically important change in global or mental state. No data were reported for relapse. No deaths were reported by the trials.

AUTHORS' CONCLUSIONS

Only three small studies provided data and the quality of reporting and evidence is low. Limited data indicate the efficacy and adverse effects profiles of chlorpromazine and penfluridol are generally similar. Penfluridol, however, may confer advantage by needing to be given only once per week. Firm conclusions are not possible without good-quality trials, and where these treatments are used, such trials are justified.

Chlorpromazine versus clotiapine for schizophrenia

BACKGROUND

Schizophrenia is a chronic, disabling and severe mental disorder, characterised by disturbance in perception, thought, language, affect and motor behaviour. Chlorpromazine and clotiapine are among antipsychotic drugs used for the treatment of people with schizophrenia.

OBJECTIVES

To determine the clinical effects, safety and cost-effectiveness of chlorpromazine compared with clotiapine for adults with schizophrenia.

SEARCH METHODS

We searched Cochrane Schizophrenia's Trials Register (last update search 16/01/2016), which is based on regular searches of CINAHL, BIOSIS, AMED, Embase, PubMed, MEDLINE, PsycINFO and clinical trials registries. There are no language, date, document type, or publication status limitations for inclusion of records in the Register.

SELECTION CRITERIA

All randomised clinical trials focusing on chlorpromazine versus clotiapine for schizophrenia. We included trials meeting our selection criteria and reporting useable data.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For binary outcomes, we calculated risk ratio (RR) and its 95% confidence interval (CI), on an intention-to-treat basis. For continuous data, we estimated the mean difference (MD) between groups and its 95% CI. We employed a random-effects model for analyses. We assessed risk of bias for included studies and created a 'Summary of findings' table using GRADE.

MAIN RESULTS

We have included four studies, published between 1974 and 2003, randomising 276 people with schizophrenia to receive either chlorpromazine or clotiapine. The studies were poor at concealing allocation of treatment and blinding of outcome assessment. Our main outcomes of interest were clinically important change in global and mental state, specific change in negative symptoms, incidence of movement disorder (dyskinesia), leaving the study early for any reason, and costs. All reported data were short-term (under six months' follow-up).The trials did not report data for the important outcomes of clinically important change in global or mental state, or cost of care. Improvement in mental state was reported using the Positive and Negative Syndrome Scale (PANSS). When chlorpromazine was compared with clotiapine the average improvement scores for mental state using the PANSS total was higher in the clotiapine group (1 RCT, N = 31, MD 11.50 95% CI 9.42 to 13.58, very low-quality evidence). The average change scores on the PANSS negative sub-scale were similar between treatment groups (1 RCT, N = 21, MD -0.97 95% CI -2.76 to 0.82, very low-quality evidence). There was no clear difference in incidence of dyskinesia (1 RCT, N = 68, RR 3.00 95% CI 0.13 to 71.15, very low-quality evidence). Similar numbers of participants left the study early from each treatment group (3 RCTs, N = 158, RR 0.68 95% CI 0.24 to 1.88, very low-quality evidence).

AUTHORS' CONCLUSIONS

Clinically important changes in global and mental state were not reported. Only one trial reported the average change in overall mental state; results favour clotiapine but these limited data are very difficult to trust due to methodological limitations of the study. The comparative effectiveness of chlorpromazine compared to clotiapine on change in global state remains unanswered. Results in this review suggest chlorpromazine and clotiapine cause similar adverse effects, although again, the quality of evidence for this is poor, making firm conclusions difficult.

Chlorpromazine versus metiapine for schizophrenia

BACKGROUND

Chlorpromazine, a widely available and inexpensive antipsychotic drug, is considered the benchmark treatment for schizophrenia worldwide. Metiapine, a dibenzothiazepine derivative, has been reported to have potent antipsychotic characteristics. However, no evidence currently exists on the effectiveness of chlorpromazine in treatment of people with schizophrenia compared to metiapine, a newer antipsychotic.

OBJECTIVES

To compare the effect of chlorpromazine versus metiapine for the treatment of people with schizophrenia SEARCH METHODS: We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials in November 2015 and 2016.

SELECTION CRITERIA

All randomised controlled trials (RCTs) focusing on chlorpromazine versus metiapine for adults with schizophrenia. We included trials meeting our selection criteria and reporting useable data.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For binary outcomes, we calculated risk ratio (RR) and its 95% confidence interval (CI), on an intention-to-treat basis. For continuous data, we estimated the mean difference between groups and its 95% CI. We employed a random-effects model for analyses. We assessed risk of bias for included studies and created 'Summary of findings' tables using GRADE.

MAIN RESULTS

We included three studies randomising 161 people with schizophrenia. Data were available for only two of our seven prestated main outcomes. Clinically important improvement in global state was measured using the Clinical Global Impression (CGI). There was no clear difference between chlorpromazine and metiapine groups (2 RCTs, n = 120, RR 1.11, 95% CI 0.84 to 1.47, very low quality evidence) and numbers of participants with parkinsonism at eight weeks were similar (2 RCTs, n = 70, RR 0.97, 95% CI 0.46 to 2.03, very low quality evidence). There were no useable data available for the other key outcomes of clinically important improvement in mental state, readmission due to relapse, satisfaction with treatment, aggressive or violent behaviour, or cost of care.

AUTHORS' CONCLUSIONS

Chlorpromazine has been the mainstay treatment for schizophrenia for decades, yet available evidence comparing this drug to metiapine fails to provide high-quality trial based data. However, the need to determine whether metiapine is more or less effective than chlorpromazine seems to be lacking in clinical relevance and future research on this comparison seems unlikely.

Chlorpromazine versus atypical antipsychotic drugs for schizophrenia

BACKGROUND

Chlorpromazine is an aliphatic phenothiazine, which is one of the widely-used typical antipsychotic drugs. Chlorpromazine is reliable for its efficacy and one of the most tested first generation antipsychotic drugs. It has been used as a 'gold standard' to compare the efficacy of older and newer antipsychotic drugs. Expensive new generation drugs are heavily marketed worldwide as a better treatment for schizophrenia, but this may not be the case and an unnecessary drain on very limited resources.

OBJECTIVES

To compare the effects of chlorpromazine with atypical or second generation antipsychotic drugs, for the treatment of people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Trials Register up to 23 September 2013.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared chlorpromazine with any other atypical antipsychotic drugs for treating people with schizophrenia. Adults (as defined in each trial) diagnosed with schizophrenia, including schizophreniform, schizoaffective and delusional disorders were included in this review.

DATA COLLECTION AND ANALYSIS

At least two review authors independently screened the articles identified in the literature search against the inclusion criteria and extracted data from included trials. For homogeneous dichotomous data, we calculated the risk ratio (RR) and the 95% confidence intervals (CIs). For continuous data, we determined the mean difference (MD) values and 95% CIs. We assessed the risk of bias in included studies and rated the quality of the evidence using the GRADE approach.

MAIN RESULTS

This review includes 71 studies comparing chlorpromazine to olanzapine, risperidone or quetiapine. None of the included trials reported any data on economic costs. 1. Chlorpromazine versus olanzapineIn the short term, there appeared to be a significantly greater clinical response (as defined in each study) in people receiving olanzapine (3 RCTs, N = 204; RR 2.34, 95% CI 1.37 to 3.99, low quality evidence). There was no difference between drugs for relapse (1 RCT, N = 70; RR 1.5, 95% CI 0.46 to 4.86, very low quality evidence), nor in average endpoint score using the Brief Psychiatric Rating Scale (BPRS) for mental state (4 RCTs, N = 245; MD 3.21, 95% CI -0.62 to 7.05,very low quality evidence). There were significantly more extrapyramidal symptoms experienced amongst people receiving chlorpromazine (2 RCTs, N = 298; RR 34.47, 95% CI 4.79 to 248.30,very low quality evidence). Quality of life ratings using the general quality of life interview (GQOLI) - physical health subscale were more favourable with people receiving olanzapine (1 RCT, N = 61; MD -10.10, 95% CI -13.93 to -6.27, very low quality evidence). There was no difference between groups for people leaving the studies early (3 RCTs, N = 139; RR 1.69, 95% CI 0.45 to 6.40, very low quality evidence). 2. Chlorpromazine versus risperidoneIn the short term, there appeared to be no difference in clinical response (as defined in each study) between chlorpromazine or risperidone (7 RCTs, N = 475; RR 0.84, 95% CI 0.53 to 1.34, low quality of evidence), nor in average endpoint score using the BPRS for mental state 4 RCTs, N = 247; MD 0.90, 95% CI -3.49 to 5.28, very low quality evidence), or any observed extrapyramidal adverse effects (3 RCTs, N = 235; RR 1.7, 95% CI 0.85 to 3.40,very low quality evidence). Quality of life ratings using the QOL scale were significantly more favourable with people receiving risperidone (1 RCT, N = 100; MD -14.2, 95% CI -20.50 to -7.90, very low quality evidence). There was no difference between groups for people leaving the studies early (one RCT, N = 41; RR 0.21, 95% CI 0.01 to 4.11, very low quality evidence). 3. Chlorpromazine versus quetiapineIn the short term, there appeared to be no difference in clinical response (as defined in each study) between chlorpromazine or quetiapine (28 RCTs, N = 3241; RR 0.93, 95% CI 0.81 to 1.06, moderate quality evidence) nor in average endpoint score using the BPRS for mental state (6 RCTs, N = 548; MD -0.18, 95% CI -1.23 to 0.88, very low quality evidence). Quality of life ratings using the GQOL1-74 scale were significantly more favourable with people receiving quetiapine (1 RCT, N = 59; MD -6.49, 95% CI -11.30 to -1.68, very low quality evidence). Significantly more people receiving chlorpromazine experienced extrapyramidal adverse effects (8 RCTs, N = 644; RR 8.03, 95% CI 4.78 to 13.51, low quality of evidence). There was no difference between groups for people leaving the studies early in the short term (12 RCTs, N = 1223; RR 1.04, 95% CI 0.77 to 1.41,moderate quality evidence).

AUTHORS' CONCLUSIONS

Most included trials included inpatients from hospitals in China. Therefore the results of this Cochrane review are more applicable to the Chinese population. Mostincluded trials were short term studies, therefore we cannot comment on the medium and long term use of chlorpromazine compared to atypical antipsychotics. Low qualityy evidence suggests chlorpromazine causes more extrapyramidal adverse effects. However, all studiesused varying dose ranges, and higher doses would be expected to be associated with more adverse events.

Definitions and drivers of relapse in patients with schizophrenia: a systematic literature review

Relapse in patients with schizophrenia has devastating repercussions, including worsening symptoms, impaired functioning, cognitive deterioration and reduced quality of life. This progressive decline exacerbates the burden of illness on patients and their families. Relapse prevention is identified as a key therapeutic aim; however, the absence of widely accepted relapse definition criteria considerably hampers achieving this goal. We conducted a literature review in order to investigate the reporting of relapses and the validity of hospitalization as a proxy for relapse in patients with schizophrenia. The primary aim was to assess the range and validity of methods used to define relapse in observational or naturalistic settings. The secondary aim was to capture information on factors that predicted or influenced the risk of relapse. A structured search of the PubMed database identified articles that discussed relapse, and hospitalization as a proxy of relapse, in patients with schizophrenia. National and international guidelines were also reviewed. Of the 150 publications and guidelines identified, 87 defined relapse and 62% of these discussed hospitalization. Where hospitalization was discussed, this was as a proxy for, or a component of, relapse in the majority of cases. However, hospitalization duration and type varied and were not always well defined. Scales were used to define relapse in 53 instances; 10 different scales were used and multiple scales often appeared within the same definition. There were 95 references to factors that may drive relapse, including non-adherence to antipsychotic medication (21/95), stress/depression (11/95) and substance abuse (9/95). Twenty-five publications discussed the potential of antipsychotic therapy to reduce relapse rates-continuous antipsychotic therapy was associated with reduced frequency and duration of hospitalization. Non-pharmacological interventions, such as psychoeducation and cognitive behavioural therapy, were also commonly reported as factors that may reduce relapse. In conclusion, this review identified numerous factors used to define relapse. Hospitalization was the factor most frequently used and represents a useful proxy for relapse when reporting in a naturalistic setting. Several factors were reported to increase the risk of relapse, and observation of these may aid the identification of at-risk patients.

Maintenance treatment with antipsychotic drugs for schizophrenia

BACKGROUND

The symptoms and signs of schizophrenia have been firmly linked to high levels of dopamine in specific areas of the brain (limbic system). Antipsychotic drugs block the transmission of dopamine in the brain and reduce the acute symptoms of the disorder. This review examined whether antipsychotic drugs are also effective for relapse prevention.

OBJECTIVES

To review the effects of maintaining antipsychotic drugs for people with schizophrenia compared to withdrawing these agents.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Specialised Register (November 2008), with additional searches of MEDLINE, EMBASE and clinicaltrials.gov (June 2011).

SELECTION CRITERIA

We included all randomised trials comparing maintenance treatment with antipsychotic drugs and placebo for people with schizophrenia or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data we calculated relative risks (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. For continuous data, we calculated mean differences (MD) or standardised mean differences (SMD) again based on a random-effects model.

MAIN RESULTS

The review currently includes 65 randomised controlled trials (RCT(s)) and 6493 participants comparing antipsychotic medication with placebo. The trials were published from 1959 to 2011 and their size ranged between 14 and 420 participants. In many studies the methods of randomisation, allocation and blinding were poorly reported. Although this and other potential sources of bias limited the overall quality, the efficacy of antipsychotic drugs for maintenance treatment in schizophrenia was clear. Antipsychotic drugs were significantly more effective than placebo in preventing relapse at seven to 12 months (primary outcome; drug 27%, placebo 64%, 24 RCT(s), n=2669, RR 0.40 CI 0.33 to 0.49, number needed to treat for an additional beneficial outcome (NNTB 3 CI 2 to 3). Hospitalisation was also reduced, however, the baseline risk was lower (drug 10%, placebo 26%, 16 RCT(s), n=2090, RR 0.38 CI 0.27 to 0.55, NNT 5 CI 4 to 9). More participants in the placebo group than in the antipsychotic drug group left the studies early due to any reason (at 7-12 months: drug 38%, placebo 66%, 18 RCT(s), n=2420, RR 0.55 CI 0.46 to 0.66, NNTB 4 CI 3 to 5) and due to inefficacy of treatment (at 7-12 months: drug 20%, placebo 50%, 18 RCT(s), n=2420, RR 0.36 CI 0.28 to 0.45, NNTB 3 CI 2 to 4). Quality of life was better in drug-treated participants (3 RCT(s), n=527, SMD -0.62 CI -1.15 to -0.09). Conversely, antipsychotic drugs as a group and irrespective of duration, were associated with more participants experiencing movement disorders (e.g. at least one movement disorder: drug 16%, placebo 9%, 22 RCT(s), n=3411, RR 1.55 CI 1.25 to 1.93, NNTH 25 CI 13 to 100), sedation (drug 13%, placebo 9%, 10 RCT(s), n=146, RR 1.50 CI 1.22 to 1.84, number needed to treat for an additional harmful outcome (NNTH) not significant) and weight gain (drug 10%, placebo 6%, 10 RCT(s), n=321, RR 2.07 CI 1.31 to 3.25, NNTH 20 CI 14 to 33). The results of the primary outcome were robust in a number of subgroup, meta-regression and sensitivity analyses, the main exception being that the drug-placebo difference in longer trials was smaller than in shorter trials.

AUTHORS' CONCLUSIONS

The results clearly demonstrate the superiority of antipsychotic drugs compared to placebo in preventing relapse. This effect must be weighed against the side effects of antipsychotic drugs. Future studies should focus on outcomes of social participation and clarify the long-term morbidity and mortality associated with these drugs.