Background: Individuals with bipolar disorder (BD) are known to have worse physical health and reduced life expectancy compared to the general population. Excess cardiovascular mortality in BD is partly attributed to metabolic syndrome and diabetes mellitus (DM), which both occur with higher-than-expected prevalence’s in this population (37.3–41.1% and 26 % respectively). Patients with comorbid BD and DM type 2 or insulin resistance have greater morbidity, lower treatment response, greater chronicity, and disability, as well as more prominent brain structure alterations. To compare the largest set of bipolar disorder pharmacotherapies to date for risk of diabetes mellitus (DM).
Materials and methods: In this study, we used electronic data available for all VHA patients nationally (51). This includes information on all VHA medical encounters (outpatient, inpatient, and long-term-care) obtained from the Austin Automation Center, VHA outpatient and inpatient prescription data from the Hospital, and death records from the Beneficiary Identification Records Locator Subsystem, a registry of all veterans who applied for VHA death benefits that is supplemented by data from Social Security records.
Result: We observed 140 patients in the four cohorts of antipsychotic initiators studied (table 1). Patients in these cohorts were broadly similar in terms of age, sex, race/ ethnicity, marital status, use of other potentially diabetogenic medications, and number of diabetes screening tests. There were slightly more women and fewer racial minority patients among the quetiapine users, and more never-married and Indian patients among those prescribed haloperidol. Otherwise, frequency distributions varied by no more than a few percentage points across the four cohorts. Average length of follow-up was also similar (just over 1 year), except for quetiapine, which was only approved for use during the study. The annual incidence (unadjusted) of new-onset diabetes over the course of follow-up ranged from 4.0 per 100 person-years of exposure in users of haloperidol to 5.8 per 100 person-years in quetiapine users.
Conclusion: Schizophrenia confers a high endogenous risk for diabetes, and the risk is further increased by both first generation and second-generation antipsychotics. Early detection and effective treatment of diabetes should be an integral part of multidisciplinary management of schizophrenia regardless of antipsychotic drug exposure.