The impact of second generation antipsychotics on insight in schizophrenia: Results from 14 randomized, placebo controlled trials.

Despite the negative impact of lack of insight on the prognosis, general functioning and treatment adherence, the effect of antipsychotic medication on insight has been investigated only in small samples and uncontrolled studies. In this study we examine whether previously reported effects of antipsychotics on insight from uncontrolled studies can be confirmed in a database including 14 randomized, double-blind, placebo-controlled trials. The database contained placebo-controlled RCTs of five second-generation antipsychotics (SGAs: olanzapine, paliperidone, quetiapine, risperidone and sertindole) and included a total of 4243 patients with schizophrenia. Insight was assessed with item G12 of the Positive and Negative Syndrome Scale (PANSS) at baseline and at six weeks. Overall, SGA treatment resulted in a significantly larger improvement in insight than placebo (0.43 points versus 0.15 points; Hedge׳s g 0.23; p<0.001). However this difference in improvement in insight was largely explained by improvement in other symptoms. In the initial analysis, one of the compounds was significantly less effective in improving insight than the other SGAs, but this difference no longer persisted when improvement in other symptoms was taken into account. The effect of SGAs on improvement in insight was not moderated by geographic region, illness duration or drop-out. The present study showed that SGA treatment of patients with schizophrenia is associated with improved insight, but that this improvement is associated with SGA induced improvements in other symptoms, though the causal relationship may not be established.