Review: new generation antipsychotic drugs may reduce relapse rates more effectively than conventional antipsychotic drugs in people with schizophrenia

摘要

This review by Leucht ef al provides important information on the efficacy of second generation "atypical" antipsychotic drugs compared with either placebo or conventional agents. It complements a large number of randomised controlled trials (RCTs) and systematic reviews that consider short term efficacy1 and goes some way to address questions about the efficacy of atypicals for the prevention of relapse.In 6 placebo and 11 conventional antipsychotic controlled RCTs, atypical antipsychotics reduced relapse compared with both placebo and conventional drugs. Furthermore, the risk of dropout due to adverse events was similar to that of placebo and showed a small, if nonsignificant, advantage over conventional compounds. The studies together involve the randomisation of more than 3000 people from a wide variety of clinical settings and are likely to be generalisable to most clinicians' clinical practice. If the results stand the test of time, then atypicals will likely be regarded as the drug of first choice for the prevention of relapse in schizophrenia.The authors state however that the advantages of atypical over conventional drugs are probably modest (NNT 13, 95% Cl 8 to 25 for relapse) and they also highlight the known problems associated with the dose of conventional drugs. RCTs using doses of conventional drugs greater than 12 mg of haloperidol tend to increase the advantages of atypicals for acute symptoms.2 It remains an important question whether the dose of conventional drugs influences the study effect size in studies which attempt to prevent relapse.