Exploring the association between atypical neuroleptic agents and diabetes mellitus in older adults

Study Objective. To explore the suggested association between atypical neuroleptic use and the development of diabetes mellitus, with a focus on older adults. Design. Retrospective cohort study. Subjects. Eleven thousand one hundred four older (> 65 yrs) residents of long-term care institutions in Ontario, Canada, who received either atypical neuroleptic agents, typical neuroleptic agents, benzodiazepines, or corticosteroids. Measurements and Main Results. Each subject was followed for the development of a diabetic event, defined as newly prescribed antidiabetic drug therapy. Our Cox regression model was adjusted for age, sex, socioeconomic status, comorbidity, and concomitant use of beta-blockers, thiazide diuretics, and antiepileptic agents. The adjusted hazard ratio for the development of diabetes in patients receiving atypical neuroleptics compared with those receiving benzodiazepines (control group) was 0.89 (95% confidence interval [CI] 0.66-1.21). The adjusted hazard ratio for typical neuroleptic users compared with the benzodiazepine group was 1.27 (95% CI 0.91-1.77). As expected, patients receiving corticosteroid therapy were almost twice as likely to develop diabetes as those receiving benzodiazepines (adjusted hazard ratio 2.2, 95% CI 1.41-3.12). For patients receiving atypical neuroleptic agents, no statistically significant difference in the percentage of diabetic events was found among individual agents (2.1% olanzapine, 1% quetiapine, 2.1% risperidone). Conclusion. Drug therapy with atypical neuroleptic agents in older adults did not increase their risk of developing diabetes mellitus.