It is well known that depression occurs in people with schizophrenia. Atypical antipsychotics are used to treat the symptoms of schizophrenia but their specific effects on those with schizophrenia and depression are unclear, although they are marketed for this purpose.
In this review we evaluated the effects of atypical antipsychotics for people with both schizophrenia and depression and unfortunately found a distinct lack of information. We wanted to assess the available evidence to ascertain whether atypical antipsychotic drugs represent a better alternative than older neuroleptic medications [plus or minus adjunctive antidepressant therapy] for people with both depression and schizophrenia. However, due to the paucity of trials of antipsychotic drugs that are sold as also having antidepressant effects, we were unable to draw any firm conclusions. More well-conducted randomised controlled trials are needed.
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 randomised trials and more trials in this important area are indicated.
Many people (up to 50%) with schizophrenia also have co-morbid depression. It has been suggested that new atypical antipsychotic drugs are beneficial for people with the two diagnoses.
To assess the effects of atypical antipsychotic drugs on people who have a diagnosis of both schizophrenia and depression.
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.
We included randomised clinical trials of atypical antipsychotic drugs used specifically for the treatment of people with a diagnosis of both schizophrenia and depression.
We extracted data independently. For homogenous dichotomous data we calculated random effects, relative risk (RR), 95% confidence intervals (CI) and, where appropriate, numbers needed to treat (NNT) on an intention-to-treat basis. For continuous data, we calculated weighted mean differences (WMD).
We found 878 citations but were only able to include three studies (five 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 CPRS -0.70 CI -1.2 to -0.2). Again, however, in the quetiapine versus 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, 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).