Suicide Among Veterans Health Administration Patients With Bipolar Disorder: Evidence for Increased Risk Associated With Benzodiazepine Receipt.

Objective: To evaluate factors associated with suicide mortality among Veterans Health Administration (VHA) patients with bipolar disorder.

Methods: VHA patients diagnosed with bipolar disorder in calendar year (CY) 2014 who utilized VHA health care services in CY2013 were included in the study cohort. Suicide mortality in the 5 years following the first documented bipolar disorder diagnosis during CY2014 was examined using Cox proportional hazards regression.

Results: 725 of 126,655 VHA patients who had a bipolar disorder diagnosis in CY2014 (0.6%) died by suicide in the following 5 CYs (2014-2019). Suicide was associated with suicide high-risk flags (hazard ratio [HR] = 2.21), prior year emergency department visit (HR = 1.25), having a new bipolar disorder diagnosis (HR= 1.23), and receiving a benzodiazepine prescription of ≥30 days of supply (HR = 1.58). Prescriptions of benzodiazepines of <30 days of supply, other anxiolytics (ie, buspirone), and sedatives were not significantly associated with suicide mortality in the multivariable model.

Conclusions: Among VHA patients diagnosed with bipolar disorder, receipt of a benzodiazepine prescription of ≥30 days was associated with increased suicide risk, even after controlling for clinical and demographic factors. Elucidating mechanisms through which benzodiazepine prescriptions increase suicide risk is an important avenue for future investigations. Additionally, VHA patients with newly diagnosed bipolar disorder may benefit from increased clinical attention, given the elevated suicide risk among this subgroup. Findings highlight targets for suicide prevention initiatives.