Atypical Antipsychotics for People With Both Schizophrenia and Depression

Background

Many people (up to 50%) with schizophrenia also have comorbid depression. It has been suggested that new atypical antipsychotic drugs are beneficial for people with the 2 diagnoses.

Objectives

To assess the effects of atypical antipsychotic drugs on people who have a diagnosis of both schizophrenia and depression.

Search Strategy

We searched the Cochrane Schizophrenia's Group Register (to March 2006). We supplemented this by citation searching and personal contact with authors and relevant pharmaceutical companies.

Selection Criteria

We included randomized clinical trials (RCTs) of atypical antipsychotic drugs used specifically for the treatment of people with a diagnosis of both schizophrenia and depression.

Data Collection and Analysis

We extracted data independently. For homogenous dichotomous data, we calculated random effects, relative risk (RR), 95% confidence intervals (CIs), and, where appropriate, numbers needed to treat on an intention-to-treat basis. For continuous data, we calculated weighted mean differences (WMD).

Main Results

We found 878 citations but were only able to include 3 studies (5 reports). One trial found no significant difference between quetiapine and haloperidol for the outcome of “less than 50% reduction in PANSS score” (n = 180, RR = 0.91, CI = 0.8 to 1.0). Those allocated sulpiride had significantly lower depression scores compared with people given chlorpromazine (1 RCT, n = 36, WMD Comprehensive Psychopathological Rating Scale = −0.70, CI = −1.2 to −0.2). Again, however, in the quetiapine vs haloperidol comparison, the continuous scoring did not highlight differences (1 RCT, n = 180, WMD PANSS depression change = −0.57, CI = −1.4 to 0.30). When clozapine was compared with any other antipsychotic drug plus an antidepressant or placebo, clozapine constantly scored better on Hamilton scores (1 RCT,¹ n = 29, WMD vs antipsychotic + mianserin = −5.53, CI = −8.23 to −2.8; 1 RCT, n = 32, WMD vs antipsychotic + meclobemide = −4.35, CI = −6.7 to −2.03; 1 RCT, n = 33, WMD vs antipsychotic + placebo = −6.35, CI = −8.6 to −4.1) (figure 1). Full details of this review are published on the Cochrane Library.²

Fig. 1.

Comparison: Clozapine Vs Other Antipsychotic + ANTIDEPRESSANT. Outcome: Mental State: Average End Point Score (Hamilton Rating Scale for Depression, High = Poor).

Authors’ Conclusions

There are too few data to guide patients, carers, clinicians, or policy makers. Current practice has to be guided by evidence other than that derived from randomized trials, and more trials in this important area are indicated.