The antipsychotic medication olanzapine is associated with type-2 diabetes onset in patients.

According to a study from the United States, “This study compared the 1-year incidence of new-onset type-2 diabetes mellitus (DM) and changes in weight in patients with a variety of psychiatric diagnoses prescribed olanzapine, risperidone, or quetiapine, compared to a reference group receiving haloperidol and no other antipsychotic medication.”

M.T. Lambert and colleagues at the University of Texas explained, Data was abstracted from charts of subjects newly initiated and then maintained for 1 year on olanzapine (n=112), risperidone (n=100), quetiapine (n=100), and haloperidol (it=100). Baseline and 1-year DM status, height, and weight were collected, as well as concurrent psychotropic medications, medical and psychiatric comorbidities.”

The results indicated, “Using a multivariate model, logistic regression identified a significant association between olanzapine (but not other atypical agents) and the development of diabetes compared to haloperidol over the 1-year period (odds ratio 8.4, 95% CI 1.8-38.7).

Baseline obesity was independently associated with new-onset DM, but only marginally greater weight gain was found among olanzapine users.”

Investigators concluded, “The middle-aged American veterans in this study cohort were highly vulnerable to the diabetogenic effects of olanzapine, but a close correlation with weight change was not found. Patients administered olanzapine should receive careful laboratory monitoring for elevated plasma, glucose in addition to weight measurement.”

Lambert and colleagues published their study in Progress in Neuro - Psychopharmacology & Biological Psychiatry (New-onset type-2 diabetes associated with atypical antipsychotic medications. Prog Neuropsychopharmacol Biol Psychiatry, 2006;30 (5):919-923).

For more information, contact M.T. Lambert, University of Texas, SW Med Center, Ft Worth Outpatient Mental Health Clinic, Ft Worth VA Mental Health Clinic, Dept. of Psychiatry, 6000 Western Pl, Suite 300, Fort Worth, TX 76107, USA.

Publisher contact information for the journal Progress in Neuro - Psychopharmacology & Biological Psychiatry is: Pergamon-Elsevier Science Ltd., the Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, England.