A total of 33 trials were included, with 4,831 patients. Nineteen trials were of patients with schizophrenia (2,389 patients), and 14 trials were of patients with bipolar disorder (2,442 patients).
Metabolic effects: Olanzapine was associated with a statistically significantly greater weight gain in patients with schizophrenia than in patients with bipolar disorder (mean weight gain 3.14kg in 18 trials versus 2.28kg in 13 trials; p=0.02).There were no significant differences between patients with schizophrenia and those with bipolar disorder, in cholesterol change (six trials for schizophrenia; seven trials for bipolar disorder), in glucose change (seven trials for schizophrenia; eight trials for bipolar disorder), and in triglyceride change (two trials for schizophrenia; four trials for bipolar disorder).
Extrapyramidal effects: There was no significant difference with olanzapine between patients with schizophrenia and those with bipolar disorder in the incidence of akathisia (11 trials for schizophrenia; eight trials for bipolar disorder), parkinsonism (six trials for schizophrenia; seven trials for bipolar disorder), and medication for Parkinson's disease (eight trials for schizophrenia; four trials for bipolar disorder).
There was evidence of statistical heterogeneity in all analyses (Ι²>50%). Sensitivity analyses indicated some differences between genders, with company sponsorship, and with different treatment duration; the full results were presented.