Antipsychotic use and the risk of diabetes in nursing home residents with dementia.

BACKGROUND: Growing evidence suggests an association between antipsychotic use and diabetes onset in schizophrenia, but little is known about this association among patients with dementia.

OBJECTIVE: The aim of this study was to quantify the association between antipsychotic use and the risk of diabetes onset among nursing home residents with dementia.

METHODS: We conducted a nested case-control study in 29,203 long-stay Medicaid-eligible residents living in nursing homes in California, Florida, Illinois, New York, and Ohio between January 2001 and December 2002 who were at least 65 years old with a dementia diagnosis and no record of diabetes within 90 days of nursing home admission. We identified 762 incident cases of diabetes and randomly selected up to 5 controls, matched on nursing home and quarter of minimum data set (MDS) assessment (N = 2646). Cases of incident diabetes were identified from MDS assessments and Medicaid claims, medication use was ascertained from Medicaid pharmacy files, and resident characteristics were obtained from MDS assessments.

RESULTS: Relative to non-users of antipsychotics, use of atypical antipsychotics was not associated with diabetes onset (adjusted odds ratio [AOR] = 1.03; 95% CI, 0.84-1.27) and risk of diabetes did not increase with length of time on treatment. Conventional antipsychotic treatment was associated with diabetes onset, particularly when treatment duration was <30 days (AOR = 2.70; 95% CI, 1.57-4.65).

CONCLUSIONS: Among nursing home residents with dementia, conventional antipsychotic therapy, particularly short-term therapy, increased their risk of developing diabetes. Atypical antipsychotic use was not associated with an increased risk of diabetes onset.