Fluphenazine versus low-potency first generation antipsychotic drugs for schizophrenia

Haloperidol versus first-generation antipsychotics for the treatment of schizophrenia and other psychotic disorders

BACKGROUND

Haloperidol is worldwide one of the most frequently used antipsychotic drugs with a very high market share. Previous narrative, unsystematic reviews found no differences in terms of efficacy between the various first-generation ("conventional", "typical") antipsychotic agents. This established the unproven psychopharmacological assumption of a comparable efficacy between the first-generation antipsychotic compounds codified in textbooks and treatment guidelines. Because this assumption contrasts with the clinical impression, a high-quality systematic review appeared highly necessary.

OBJECTIVES

To compare the efficacy, acceptability, and tolerability of haloperidol with other first-generation antipsychotics in schizophrenia and schizophrenia-like psychosis.

SEARCH METHODS

In October 2011 and July 2012, we searched the Cochrane Schizophrenia Group's Trials Register, which is based on regular searches of CINAHL, BIOSIS, AMED, EMBASE, PubMed, MEDLINE, PsycINFO, and registries of clinical trials. To identify further relevant publications, we screened the references of all included studies and contacted the manufacturers of haloperidol for further relevant trials and missing information on identified studies. Furthermore, we contacted the corresponding authors of all included trials for missing data.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that compared oral haloperidol with another oral first-generation antipsychotic drug (with the exception of the low-potency antipsychotics chlorpromazine, chlorprothixene, levopromazine, mesoridazine, perazine, prochlorpromazine, and thioridazine) in schizophrenia and schizophrenia-like psychosis. Clinically important response to treatment was defined as the primary outcome. Secondary outcomes were global state, mental state, behaviour, overall acceptability (measured by the number of participants leaving the study early due to any reason), overall efficacy (attrition due to inefficacy of treatment), overall tolerability (attrition due to adverse events), and specific adverse effects.

DATA COLLECTION AND ANALYSIS

At least two review authors independently extracted data from the included trials. The methodological quality of the included studies was assessed using The Cochrane Collaboration`s 'Risk of bias' tool.We analysed dichotomous outcomes with risk ratios (RR) and continuous outcomes with mean differences (MD), both with the associated 95% confidence intervals (CI). All analyses were based on a random-effects model and we preferably used data on an intention-to-treat basis where possible.

MAIN RESULTS

The systematic review currently includes 63 randomised trials with 3675 participants. Bromperidol (n = 9), loxapine (n = 7), and trifluoperazine (n = 6) were the most frequently administered antipsychotics comparator to haloperidol. The included studies were published between 1962 and 1993, were characterised by small sample sizes (mean: 58 participants, range from 18 to 206) and the predefined outcomes were often incompletely reported. All results for the main outcomes were based on very low or low quality data. In many trials the mechanism of randomisation, allocation, and blinding was frequently not reported. In short-term studies (up to 12 weeks), there was no clear evidence of a difference between haloperidol and the pooled group of the other first-generation antipsychotic agents in terms of the primary outcome "clinically important response to treatment" (40 RCTs, n = 2132, RR 0.93 CI 0.87 to 1.00). In the medium-term trials, haloperidol may be less effective than the other first-generation antipsychotic group but this evidence is based on only one trial (1 RCT, n = 80, RR 0.51 CI 0.37 to 0.69).Based on limited evidence, haloperidol alleviated more positive symptoms of schizophrenia than the other antipsychotic drugs. There were no statistically significant between-group differences in global state, other mental state outcomes, behaviour, leaving the study early due to any reason, due to inefficacy, as well as due to adverse effects. The only statistically significant difference in specific side effects was that haloperidol produced less akathisia in the medium term.

AUTHORS' CONCLUSIONS

The findings of the meta-analytic calculations support the statements of previous narrative, unsystematic reviews suggesting comparable efficacy of first-generation antipsychotics. In efficacy-related outcomes, there was no clear evidence of a difference between the prototypal drug haloperidol and other, mainly high-potency first-generation antipsychotics. Additionally, we demonstrated that haloperidol is characterised by a similar risk profile compared to the other first-generation antipsychotic compounds. The only statistically significant difference in specific side effects was that haloperidol produced less akathisia in the medium term. The results were limited by the low methodological quality in many of the included original studies. Data for the main results were low or very low quality. Therefore, future clinical trials with high methodological quality are required.

Perphenazine versus low-potency first-generation antipsychotic drugs for schizophrenia

BACKGROUND

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between the various first-generation antipsychotics, however, low-potency first-generation antipsychotic drugs are sometimes perceived as less efficacious than high-potency first-generation compounds by clinicians, and they also seem to differ in their side effects.

OBJECTIVES

To review the effects of high-potency, first-generation perphenazine compared with low-potency, first-generation antipsychotic drugs for people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (October 2010).

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing perphenazine with first-generation, low-potency antipsychotic drugs 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 (CI) on an intention-to-treat basis and using a random-effects model.

MAIN RESULTS

The review currently includes four relevant randomised trials with 365 participants. The size of the included studies was between 42 and 158 participants with a study length between one and four months. Overall, the methods of sequence generation and allocation concealment were poorly reported. Most studies were rated as low risk of bias in terms of blinding. Overall, attrition bias in the studies was high.The effects of perphenazine and low-potency antipsychotic drugs seemed to be similar in terms of the primary outcome - response to treatment (perphenazine 58%, low-potency antipsychotics 59%, 2 RCTs, n = 138, RR 0.97 CI 0.74 to 1.26 - moderate quality of evidence). There was also no clear evidence of a difference in acceptability of treatment with the number of participants leaving the studies early due to any reason, however results were imprecise (perphenazine 30%, low-potency antipsychotics 28%, 3 RCTs, n = 323, RR 0.78 CI 0.35 to 1.76, very low quality of evidence).There were low numbers of studies available for the outcomes experiencing at least one adverse effect (perphenazine 33%, low-potency antipsychotics 47%, 2 RCTs, n = 165, RR 0.83 CI 0.36 to 1.95, low quality evidence) and experiencing at least one movement disorder (perphenazine 22%, low-potency first-generation antipsychotics 0%, 1 RCT, n = 69, RR 15.62 CI 0.94 to 260.49, low quality evidence), and the confidence intervals for the estimated effects did not exclude important differences. Akathisia was more frequent in the perphenazine group (perphenazine 25%, low-potency antipsychotics 22%, 2 RCTs, n = 227, RR 9.45 CI 1.69 to 52.88), whereas severe toxicity was less so (perphenazine 42%, low-potency antipsychotics 69%, 1 RCT, n = 96, RR 0.61 CI 0.41 to 0.89).There were three deaths in the low-potency group by four months but the difference between groups was not significant (perphenazine 0%, low-potency antipsychotics 2%, 1 RCT, n = 96, RR 0.14 CI 0.01 to 2.69, moderate quality evidence). No data were available for our prespecified outcomes of interest sedation or quality of life. Data were not available for other outcomes such as relapse, service use, costs and satisfaction with care.The event rates reported quote simple aggregates and are not based on the RRs.

AUTHORS' CONCLUSIONS

The results do not show a superiority in efficacy of high-potency perphenazine compared with low-potency first-generation antipsychotics. There is some evidence that perphenazine is more likely to cause akathisia and less likely to cause severe toxicity, but most adverse effect results were equivocal. The number of studies as well as the quality of studies is low, with quality of evidence for the main outcomes ranging from moderate to very low, so more randomised evidence would be needed for conclusions to be made.

Flupenthixol versus low-potency first-generation antipsychotic drugs for schizophrenia

BACKGROUND

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between antipsychotic drugs, however, low-potency antipsychotic drugs are sometimes perceived as less efficacious than high-potency compounds by clinicians, and they also seem to differ in their side effects.

OBJECTIVES

To review the effects in clinical response of flupenthixol and low-potency antipsychotics for people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (July 2010).

SELECTION CRITERIA

Randomised controlled trials that compared flupenthixol with first-generation low-potency antipsychotic drugs for people with schizophrenia or schizophrenia-like psychosis.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For continuous data, we calculated mean differences (MD) based on a random-effects model.

MAIN RESULTS

The review currently includes one randomised trial from mainland China with 153 participants that lasted two months and compared flupenthixol with chlorpromazine. The exact methods of sequence generation and allocation concealment were not reported, and medication was provided in an open manner. There were no data on the outcomes that we had a priori selected for a 'Summary of findings' table.There was no significant difference between flupenthixol and chlorpromazine in the participants' general mental state at endpoint as measured by the Brief Psychiatric Rating Scale (BPRS) total score (1 randomised controlled trial (RCT), n = 153, MD 2.20 95% confidence interval (CI) -1.25 to 5.65). Chlorpromazine was associated with significantly less dizziness (1 RCT, n = 153, MD 0.12 95% CI 0.01 to 0.23); dystonia (1 RCT, n = 153, MD 0.29 95% CI 0.13 to 0.45); unsteady gait (1 RCT, n = 153, MD 0.46 95% CI 0.28 to 0.64); reduced facial expression (1 RCT, n = 153, MD 0.27 95% CI 0.09 to 0.45); restlessness (1 RCT, n = 153, MD 0.69 95% CI 0.45 to 0.93); rigidity (elbow) (1 RCT, n = 153, MD 0.48 95% CI 0.28 to 0.68); and tremor (1 RCT, n = 153, MD 0.56 95% CI 0.34 to 0.78). Chlorpromazine produced more dryness of mouth than flupenthixol (1 RCT, n = 153, MD -0.14 95% CI -0.25 to -0.03).

AUTHORS' CONCLUSIONS

The evidence base of flupenthixol versus low-potency first-generation antipsychotics is currently restricted to one randomised comparison with chlorpromazine. The few reported data do not suggest a difference in efficacy, but flupenthixol appeared to produce more movement disorders and dizziness, while chlorpromazine was associated with the anticholinergic side effect - dryness of mouth. More trials are needed to make conclusions about the relative effects of flupenthixol and low-potency antipsychotics.

Haloperidol versus low-potency first-generation antipsychotic drugs for schizophrenia

BACKGROUND

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between antipsychotic compounds, however, low-potency antipsychotic drugs are often clinically perceived as less efficacious than high-potency compounds, and they also seem to differ in their side-effects.

OBJECTIVES

To review the effects in clinical response of haloperidol and low-potency antipsychotics for people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (July 2010).

SELECTION CRITERIA

We included all randomised trials comparing haloperidol with first-generation low-potency antipsychotic drugs for people with schizophrenia or schizophrenia-like psychosis.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data, we calculated risk ratios (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), again based on a random-effects model.

MAIN RESULTS

The review currently includes 17 randomised trials and 877 participants. The size of the included studies was between 16 and 109 participants. All studies were short-term with a study length between two and 12 weeks. Overall, sequence generation, allocation procedures and blinding were poorly reported. We found no clear evidence that haloperidol was superior to low-potency antipsychotic drugs in terms of clinical response (haloperidol 40%, low-potency drug 36%, 14 RCTs, n = 574, RR 1.11, CI 0.86 to 1.44 lowquality evidence). There was also no clear evidence of benefit for either group in acceptability of treatment with equivocal difference in the number of participants leaving the studies early due to any reason (haloperidol 13%, low-potency antipsychotics 17%, 11 RCTs, n = 408, RR 0.82, CI 0.38 to 1.77, low quality evidence). Similar equivocal results were found between groups for experiencing at least one adverse effect (haloperidol 70%, low-potency antipsychotics 35%, 5 RCTs n = 158, RR 1.97, CI 0.69 to 5.66, very low quality evidence ). More participants from the low-potency drug group experienced sedation (haloperidol 14%, low-potency antipsychotics 41%, 2 RCTs, n = 44, RR 0.30, CI 0.11 to 0.82, moderate quality evidence), orthostasis problems (haloperidol 25%, low-potency antipsychotics 71%, 1 RCT, n = 41, RR 0.35, CI 0.16 to 0.78) and weight gain (haloperidol 5%, low-potency antipsychotics 29%, 3 RCTs, n = 88, RR 0.22, CI 0.06 to 0.81). In contrast, the outcome 'at least one movement disorder' was more frequent in the haloperidol group (haloperidol 72%, low-potency antipsychotics 41%, 5 RCTs, n = 170, RR 1.64, CI 1.22 to 2.21, low quality evidence). No data were available for death or quality of life. The results of the primary outcome were robust in several subgroup and sensitivity analyses.

AUTHORS' CONCLUSIONS

The results do not clearly show a superiority in efficacy of haloperidol compared with low-potency antipsychotics. Differences in adverse events were found for movement disorders, which were more frequent in the haloperidol group, and orthostatic problems, sedation and weight gain, which were more frequent in the low-potency antipsychotic group. The quality of studies was low, and the quality of evidence for the main outcomes of interest varied from moderate to very low, so more newer studies would be needed in order to draw a definite conclusion about whether or not haloperidol is superior or inferior to low-potency antipsychotics.

Trifluoperazine versus low-potency first-generation antipsychotic drugs for schizophrenia

BACKGROUND

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between any other antipsychotic compounds, however, low-potency antipsychotic drugs are often perceived as less efficacious than high-potency compounds by clinicians, and they also seem to differ in their side-effects.

OBJECTIVES

To review the effects in response to treatment of trifluoperazine and low-potency antipsychotics for people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Trials Register (November 2010).

SELECTION CRITERIA

We included all randomised trials comparing trifluoperazine with first-generation low-potency antipsychotic drugs for people with schizophrenia or schizophrenia-like psychosis.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model.

MAIN RESULTS

The review currently includes seven randomised trials involving 422 participants that compared trifluoperazine with low-potency antipsychotic drugs. The size of the included studies was between 20 and 157 participants with a study length between four and 52 weeks. Overall, sequence generation, allocation procedures and blinding were poorly reported. Trifluoperazine was not significantly different from low-potency antipsychotic drugs in terms of response to treatment (trifluoperazine 26%, low-potency drug 27%, 3 RCTs, n = 120, RR 0.96 CI 0.59 to 1.56, moderate quality evidence). There was also no significant difference in acceptability of treatment with equivocal number of participants leaving the studies early due to any reason (trifluoperazine 20%, low-potency antipsychotics 16%, 3 RCTs, n = 239, RR 1.25, CI 0.72 to 2.17,low quality evidence). There was no significant difference in numbers with at least one adverse effect (trifluoperazine 60%, low-potency antipsychotics 38%, 1 RCT, n = 60, RR 1.60, CI 0.94 to 2.74, moderate quality evidence). However, at least one movement disorder was significantly more frequent in the trifluoperazine group (trifluoperazine 23%, low-potency antipsychotics 13%, 2 RCTs, n = 123, RR 2.08 CI 0.78 to 5.55, very low quality evidence) as well as incoordination (trifluoperazine 20%, low-potency antipsychotics 5%, 1 RCT, n = 60, RR 7.00, CI 1.60 to 30.66) and rigor (trifluoperazine 45%, low-potency antipsychotics 10%, 1 RCT, n = 60, RR 4.50, CI 1.58 to 12.84). No data were available for other outcomes of interest death, sedation and quality of life.

AUTHORS' CONCLUSIONS

The results did not show a difference in efficacy between trifluoperazine and low-potency antipsychotics. Trifluoperazine produced more movement disorders. The number of randomised studies as well as their quality is low, the quality of evidence for outcomes of interest ranged from moderate to very low quality, so more, newer studies would be needed for conclusions about the relative effects of trifluoperazine and low-potency antipsychotics.