Abstract
Background: Bipolar disorder (BD) is a severe and chronic mental illness characterized by periods of mania/ hypomania and depression. Both disease phases are associated with increased risk of acquiring HIV. Despite this, use of highly effective preexposure prophylaxis (PrEP) for HIV prevention among people with BD is poorly understood. Methods: We performed a retrospective cohort study using the Merative MarketScan Claims Database from 2010-2022 to identify people with BD. Additional clinical variables including outpatient encounters for sexually transmitted infections (STIs), use of long-acting injectable agents, psychiatric hospitalizations, and outpatient encounters with primary care providers (PCPs) and psychiatrists were included. Results: There were 333,867 people with BD (61.9% female) in the cohort. A total of 435 new HIV diagnoses were identified, with diagnoses more common among males (adjusted odds ratio [aOR] [95% CI]=5.30 [4.22-6.65], P<.001) and those with comorbid stimulant use disorder (aOR [95% CI]=2.40 [1.71-3.39], P<.001). A total of 1,337 people with BD were prescribed PrEP, and 909 were prescribed at least 3 months of PrEP. Among people with ≥4 encounters for STIs, 3.53% (n=246) were prescribed PrEP of any duration, and 2.73% (n=190) were prescribed PrEP for at least 3 months. People with BD who had outpatient encounters only with psychiatrists had greater odds of HIV diagnosis compared to those who had follow-up encounters with PCPs only (aOR [95% CI]=1.58 [1.11-2.27], P=.01) and lower odds of receiving PrEP prescription (aOR [95% CI]=0.74 [0.56-0.98], P=.03). Conclusions: PrEP use among commercially insured people with BD was critically low, with <1% prescribed PrEP. Even among those with multiple encounters for STIs, <4% were prescribed PrEP, despite this being an indication for prescription. Engagement of people with BD in the PrEP care continuum is essential for ending the HIV pandemic, and integration of PrEP prescription with psychiatric care may represent an efficient method for increasing PrEP use.