Impact of olanzapine or risperidone treatment on insulin sensitivity in schizophrenia or schizoaffective disorder.

Journal Article (Journal Article)

AIM: To assess changes in insulin sensitivity in non-diabetic adults with schizophrenia or schizoaffective disorder treated with olanzapine or risperidone. METHODS: One hundred and thirty patients were randomly assigned to 12 weeks double-blind treatment with olanzapine or risperidone. Insulin sensitivity was measured using a two-step euglycaemic, hyperinsulinaemic clamp procedure. Whole-body adiposity was measured using dual-energy X-ray absorptiometry. The primary endpoint was the within-group change from baseline in insulin sensitivity normalized to fat-free mass (M(ffm) /I) during the clamp procedure's low-insulin phase, using an analysis of covariance model including the covariate weight change. RESULTS: Forty-one olanzapine-treated and 33 risperidone-treated patients completed baseline and endpoint clamp measurements. Mean M(ffm) /I during the low-insulin phase declined 9.0% (p = 0.226) in olanzapine-treated patients and 13.2% (p = 0.047) in risperidone-treated patients (between-group difference p = 0.354). During the high-insulin phase, M(ffm) /I declined 10.4% (p = 0.036) in olanzapine-treated patients and 2.1% (p = 0.698) in risperidone-treated patients (between-group difference p = 0.664). Changes in M(ffm) /I correlated inversely with changes in body weight and adiposity, which were generally higher in olanzapine-treated patients. Significant within-group increases in fasting glucose, but not haemoglobin A1c (HbA1c), were observed during olanzapine treatment. The fasting glucose change was not correlated with M(ffm) /I changes. CONCLUSIONS: Small, but statistically significant, decrements in insulin sensitivity were observed in olanzapine- and risperidone-treated patients at 1 of 2 insulin doses tested. Significant increases in fasting glucose and insulin and total fat mass were observed only in olanzapine-treated patients. Changes in insulin sensitivity correlated significantly with changes in weight or adiposity, but not with changes in glucose.

Full Text

Duke Authors

Cited Authors

  • Hardy, TA; Henry, RR; Forrester, TD; Kryzhanovskaya, LA; Campbell, GM; Marks, DM; Mudaliar, S

Published Date

  • August 2011

Published In

Volume / Issue

  • 13 / 8

Start / End Page

  • 726 - 735

PubMed ID

  • 21435142

Electronic International Standard Serial Number (EISSN)

  • 1463-1326

Digital Object Identifier (DOI)

  • 10.1111/j.1463-1326.2011.01398.x


  • eng

Conference Location

  • England