Aripiprazole versus typicals for schizophrenia

  • Review
  • Intervention

Authors

  • J Bhattacharjee,

  • HGG El-Sayeh


Dr Jayanti Bhattacharjee, Cygnet Hospital at Bierley, Bierley Lane, Bierley, Bradford, BD4 6AD, UK. jayantibhattacharjee@hotmail.com.

Abstract

Background

Aripiprazole is a relatively new antipsychotic drug, said to be the prototype of a new third generation of antipsychotics; the so-called dopamine-serotonin system stabilisers. In this review we examine how the efficacy and tolerability of aripiprazole differs from that of typical antipsychotics.

Objectives

To evaluate the effects of aripiprazole compared with other typical antipsychotics for people with schizophrenia and schizophrenia-like psychoses.

Search strategy

We searched the Cochrane Schizophrenia Group Trials Register (May 2007) which is based on regular searches of BIOSIS, CENTRAL, CINAHL, EMBASE, MEDLINE and PsycINFO.

Selection criteria

We included all randomised trials comparing aripiprazole with typical antipsychotics in people with schizophrenia or schizophrenia-like psychosis.

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. We calculated numbers needed to treat/harm (NNT/NNH) where appropriate. For continuous data, we calculated weighted mean differences (WMD) again based on a random effects model. We have contacted representatives of Bristol Myers Squibb pharmaceuticals (UK) for additional and missing data.

Main results

We included nine randomised trials involving 3122 people comparing aripiprazole with typical antipsychotic drugs. None of the studies reported on relapse - our primary outcome of interest. Attrition from studies was high and data reporting poor. Participants given aripiprazole were comparable to those receiving typical drugs in improving global state and mental state. Aripiprazole provided a significant advantage over typical antipsychotics in terms of fewer occurrences of extra-pyramidal symptom (n=968, 3 RCT, RR 0.46 CI 0.3 to 0.9, NNT 13 CI 17 to 10), and particularly akathisia (n=897, 3 RCT, RR 0.39 CI 0.3 to 0.6, NNT 11 CI 14 to 9). Fewer participants given aripiprazole developed hyperprolactinaemia (n=300, 1 RCT, RR 0.07 CI 0.03 to 0.2, NNT 2 CI 3 to 1) and raised fasting blood glucose (n=360, 1 RCT, RR 0.65 CI 0.5 to 0.9, NNT 8 CI 14 to 6). Aripiprazole presented a lesser risk of sinus tachycardia (n=289, 1 RCT, RR 0.09 CI 0.01 to 0.8, NNT 22 CI 63 to 13) and blurred vision (n=308, 1 RCT, RR 0.19 CI 0.1 to 0.7, NNT 14 CI 25 to 10); but enhanced risk of occurrence of dizziness (n=957, 3 RCTs, RR 1.88 CI 1.1 to 3.2, NNH 20 CI 33 to 14) and nausea (n=957, 3 RCTs, RR 3.03 CI 1.5 to 6.1, NNH 17 CI 25 to 13). Attrition rates were high in both groups, although significantly more participants in the aripiprazole group completed the study in the long term (n=1294, 1 RCT, RR 0.81 CI 0.8 to 0.9 NNT 8 CI 5 to 14).

Authors' conclusions

Aripiprazole is not much different from typical antipsychotic drugs with respect to efficacy. However it presents significant advantages in terms of tolerability due to its favourable adverse effects profile. This might enhance its effectiveness in encouraging compliance. Clearly reported pragmatic short, medium and long term randomised controlled trials are required to replicate and validate these findings and determine the position of aripiprazole in everyday clinical practice.

Plain language summary

Plain language summary

Plain language summary
Schizophrenia is a serious, chronic and relapsing mental illness with a worldwide lifetime prevalence of about one percent.

First generation 'typical' antipsychotics such as chlorpromazine and haloperidol have been the mainstay of treatment and do provide a treatment response for most people with schizophrenia, whether that is a reduction in psychotic episodes or a lessening in the severity of their illness. However, a proportion of people still do not respond adequately to antipsychotic medication. Additionally, antipsychotics are associated with serious adverse effects which can often compromise compliance with medication and therefore increase the incidences of relapse.

Aripiprazole is one of a new third generation of antipsychotic drugs; the so called dopamine-serotonin system stabilisers. Aripiprazole is not significantly different from typical drugs (haloperidol, perphenazine, chlorpromazine) in respect of efficacy. It has a favourable adverse effects profile, presents a significantly lesser risk of causing extra-pyramidal symptoms: hyperprolactinaemia, raised blood glucose and sinus tachycardia, and is more commonly associated with nausea and dizziness. It confers a significant advantage over typical drugs in terms of tolerability and is therefore more effective in encouraging compliance.