Typical antipsychotics for psychosis in adolescents

Haloperidol (oral) versus olanzapine (oral) for people with schizophrenia and schizophrenia-spectrum disorders

BACKGROUND

Schizophrenia is often a severe and disabling psychiatric disorder. Antipsychotics remain the mainstay of psychotropic treatment for people with psychosis. In limited resource and humanitarian contexts, it is key to have several options for beneficial, low-cost antipsychotics, which require minimal monitoring. We wanted to compare oral haloperidol, as one of the most available antipsychotics in these settings, with a second-generation antipsychotic, olanzapine.

OBJECTIVES

To assess the clinical benefits and harms of haloperidol compared to olanzapine for people with schizophrenia and schizophrenia-spectrum disorders.

SEARCH METHODS

We searched the Cochrane Schizophrenia study-based register of trials, which is based on monthly searches of CENTRAL, CINAHL, ClinicalTrials.gov, Embase, ISRCTN, MEDLINE, PsycINFO, PubMed and WHO ICTRP. We screened the references of all included studies. We contacted relevant authors of trials for additional information where clarification was required or where data were incomplete. The register was last searched on 14 January 2023.

SELECTION CRITERIA

Randomised clinical trials comparing haloperidol with olanzapine for people with schizophrenia and schizophrenia-spectrum disorders. Our main outcomes of interest were clinically important change in global state, relapse, clinically important change in mental state, extrapyramidal side effects, weight increase, clinically important change in quality of life and leaving the study early due to adverse effects.

DATA COLLECTION AND ANALYSIS

We independently evaluated and extracted data. For dichotomous outcomes, we calculated risk ratios (RR) and their 95% confidence intervals (CI) and the number needed to treat for an additional beneficial or harmful outcome (NNTB or NNTH) with 95% CI. For continuous data, we estimated mean differences (MD) or standardised mean differences (SMD) with 95% CIs. For all included studies, we assessed risk of bias (RoB 1) and we used the GRADE approach to create a summary of findings table.

MAIN RESULTS

We included 68 studies randomising 9132 participants. We are very uncertain whether there is a difference between haloperidol and olanzapine in clinically important change in global state (RR 0.84, 95% CI 0.69 to 1.02; 6 studies, 3078 participants; very low-certainty evidence). We are very uncertain whether there is a difference between haloperidol and olanzapine in relapse (RR 1.42, 95% CI 1.00 to 2.02; 7 studies, 1499 participants; very low-certainty evidence). Haloperidol may reduce the incidence of clinically important change in overall mental state compared to olanzapine (RR 0.70, 95% CI 0.60 to 0.81; 13 studies, 1210 participants; low-certainty evidence). For every eight people treated with haloperidol instead of olanzapine, one fewer person would experience this improvement. The evidence suggests that haloperidol may result in a large increase in extrapyramidal side effects compared to olanzapine (RR 3.38, 95% CI 2.28 to 5.02; 14 studies, 3290 participants; low-certainty evidence). For every three people treated with haloperidol instead of olanzapine, one additional person would experience extrapyramidal side effects. For weight gain, the evidence suggests that there may be a large reduction in the risk with haloperidol compared to olanzapine (RR 0.47, 95% CI 0.35 to 0.61; 18 studies, 4302 participants; low-certainty evidence). For every 10 people treated with haloperidol instead of olanzapine, one fewer person would experience weight increase. A single study suggests that haloperidol may reduce the incidence of clinically important change in quality of life compared to olanzapine (RR 0.72, 95% CI 0.57 to 0.91; 828 participants; low-certainty evidence). For every nine people treated with haloperidol instead of olanzapine, one fewer person would experience clinically important improvement in quality of life. Haloperidol may result in an increase in the incidence of leaving the study early due to adverse effects compared to olanzapine (RR 1.99, 95% CI 1.60 to 2.47; 21 studies, 5047 participants; low-certainty evidence). For every 22 people treated with haloperidol instead of olanzapine, one fewer person would experience this outcome. Thirty otherwise relevant studies and several endpoints from 14 included studies could not be evaluated due to inconsistencies and poor transparency of several parameters. Furthermore, even within studies that were included, it was often not possible to use data for the same reasons. Risk of bias differed substantially for different outcomes and the certainty of the evidence ranged from very low to low. The most common risks of bias leading to downgrading of the evidence were blinding (performance bias) and selective reporting (reporting bias).

AUTHORS' CONCLUSIONS

Overall, the certainty of the evidence was low to very low for the main outcomes in this review, making it difficult to draw reliable conclusions. We are very uncertain whether there is a difference between haloperidol and olanzapine in terms of clinically important global state and relapse. Olanzapine may result in a slightly greater overall clinically important change in mental state and in a clinically important change in quality of life. Different side effect profiles were noted: haloperidol may result in a large increase in extrapyramidal side effects and olanzapine in a large increase in weight gain. The drug of choice needs to take into account side effect profiles and the preferences of the individual. These findings and the recent inclusion of olanzapine alongside haloperidol in the WHO Model List of Essential Medicines should increase the likelihood of it becoming more easily available in low- and middle- income countries, thereby improving choice and providing a greater ability to respond to side effects for people with lived experience of schizophrenia. There is a need for additional research using appropriate and equivalent dosages of these drugs. Some of this research needs to be done in low- and middle-income settings and should actively seek to account for factors relevant to these. Research on antipsychotics needs to be person-centred and prioritise factors that are of interest to people with lived experience of schizophrenia.

Atypical antipsychotics for psychosis in adolescents

BACKGROUND

Schizophrenia often presents in adolescence, but current treatment guidelines are based largely on studies of adults with psychosis. Over the past decade, the number of studies on treatment of adolescent-onset psychosis has increased. The current systematic review collates and critiques evidence obtained on the use of various atypical antipsychotic medications for adolescents with psychosis.

OBJECTIVES

To investigate the effects of atypical antipsychotic medications in adolescents with psychosis. We reviewed in separate analyses various comparisons of atypical antipsychotic medications with placebo or a typical antipsychotic medication or another atypical antipsychotic medication or the same atypical antipsychotic medication but at a lower dose.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Register (October 2011), which is based on regular searches of BIOSIS, CENTRAL, CINAHL, EMBASE, MEDLINE and PsycINFO. We inspected references of all identified studies and contacted study authors and relevant pharmaceutical companies to ask for more information.

SELECTION CRITERIA

We included all relevant randomised controlled trials (RCTs) that compared atypical antipsychotic medication with placebo or another pharmacological intervention or with psychosocial interventions, standard psychiatric treatment or no intervention in children and young people aged 13 to 18 years with a diagnosis of schizophrenia, schizoaffective disorder, acute and transient psychoses or unspecified psychosis. We included studies published in English and in other languages that were available in standardised databases.

DATA COLLECTION AND ANALYSIS

Review authors AK and SSD selected the studies, rated the quality of the studies and performed data extraction. For dichotomous data, we estimated risk ratios (RRs) with 95% confidence intervals (CIs) using a fixed-effect model. When possible, for binary data presented in the 'Summary of findings' table, we calculated illustrative comparative risks. We summated continuous data using the mean difference (MD). Risk of bias was assessed for included studies.

MAIN RESULTS

We included 13 RCTs, with a total of 1112 participants. We found no data on service utilisation, economic outcomes, behaviour or cognitive response. Trials were classified into the following groups. 1. Atypical antipsychotics versus placebo: Only two studies compared one atypical antipsychotic medication with placebo. In one study, the number of non-responders treated with olanzapine was not different from the number treated with placebo (1 RCT, n = 107, RR 0.84, 95% CI 0.65 to 1.10); however, significantly more (57% vs 32%) people left the study early (1 RCT, n = 107, RR 0.56, 95% CI 0.36 to 0.87) from the placebo group compared with the olanzapine group. With regard to adverse effects, young people treated with aripiprazole had significantly lower serum cholesterol compared with those given placebo (1 RCT, n = 302, RR 3.77, 95% CI 1.88 to 7.58). 2. Atypical antipsychotics versus typical antipsychotics: When the findings of all five trials comparing atypical antipsychotic medications with a typical antipsychotic medication were collated, no difference in the mean end point Brief Psychiatric Rating Scale (BPRS) score was noted between the two arms (5 RCTs, n = 236, MD -1.08, 95% CI -3.08 to 0.93). With regard to adverse effects, the mean end point serum prolactin concentration was much higher than the reference range for treatment with risperidone, olanzapine and molindone in one of the studies. However, fewer adolescents who were receiving atypical antipsychotic medications left the study because of adverse effects (3 RCTs, n = 187, RR 0.65, 95% CI 0.36 to 1.15) or for any reason (3 RCTs, n = 187, RR 0.62, 95% CI 0.39 to 0.97).3. One atypical antipsychotic versus another atypical antipsychotic: The mean end point BPRS score was not significantly different for people who received risperidone compared with those who received olanzapine; however, the above data were highly skewed. Overall no difference was noted in the number of people leaving the studies early because of any adverse effects between each study arm in the three studies comparing olanzapine and risperidone (3 RCTs, n = 130, RR 1.15, 95% CI 0.44 to 3.04). Specific adverse events were not reported uniformly across the six different studies included in this section of the review; therefore it was difficult to do a head-to-head comparison of adverse events for different atypical antipsychotic medications.4. Lower-dose atypical antipsychotic versus standard/higher-dose atypical antipsychotic: Three studies reported comparisons of lower doses of the atypical antipsychotic medication with standard/higher doses of the same medication. One study reported better symptom reduction with a standard dose of risperidone as compared with a low dose (1 RCT, n = 257, RR -8.00, 95% CI -13.75 to -2.25). In another study, no difference was reported in the number of participants not achieving remission between the group receiving 10 mg/d and those who received 30 mg/d of aripiprazole (1 RCT, n = 196, RR 0.84, 95% CI 0.48 to 1.48). Similarly in the other study, authors reported no statistically significant difference in clinical response between the two groups receiving lower-dose (80 mg/d) and higher-dose (160 mg/d) ziprasidone, as reflected by the mean end point BPRS score (1 RCT, n = 17, MD -4.40, 95% CI -19.20 to 10.40).

AUTHORS' CONCLUSIONS

No convincing evidence suggests that atypical antipsychotic medications are superior to typical medications for the treatment of adolescents with psychosis. However, atypical antipsychotic medications may be more acceptable to young people because fewer symptomatic adverse effects are seen in the short term. Little evidence is available to support the superiority of one atypical antipsychotic medication over another, but side effect profiles are different for different medications. Treatment with olanzapine, risperidone and clozapine is often associated with weight gain. Aripiprazole is not associated with increased prolactin or with dyslipidaemia. Adolescents may respond better to standard-dose as opposed to lower-dose risperidone, but for aripiprazole and ziprasidone, lower doses may be equally effective. Future trials should ensure uniform ways of reporting.