Prediction of long-term metabolic effects of olanzapine and risperidone treatment from baseline body mass index in schizophrenia and bipolar disorder.

Baseline body mass index (BMI), baseline BMI status (normal, overweight, obese) and early (1 month) BMI increases were tested as predictors of 6- and 12-month increases in glucose and lipid measures in 82 olanzapine (OLZ)- and 78 risperidone (RIS)-treated patients with schizophrenia, schizoaffective disorder, or bipolar disorder who participated in a 12-month randomized, prospective metabolic effects study. Baseline BMI predicted greater fasting glucose and HgbA1c levels at 12 months for both treatments. Early BMI change predicted fasting glucose levels at 6 months, but not HgbA1c or BMI, at either time point.