Pain, Substance Use Disorders, Mental Health, and Buprenorphine Treatment among Patients With and Without HIV.

Treatment of opioid use disorder (OUD) with buprenorphine improves outcomes and mortality among people with HIV (PWH). However, engagement is low and is influenced by comorbidities. We examined the impact of patterns of co-occurring pain, substance use disorders (SUDs), and mental health diagnoses on buprenorphine initiation and retention in PWH. The Veterans Aging Cohort Study contained 7,875 patients (2,702 PWH and 5,173 without HIV) with new OUD clinical encounters (2008-2017). Buprenorphine initiation and retention were derived from prescription data. We identified patterns of co-occurring diagnoses (via ICD codes) and assessed the effects of class membership on both outcomes using latent class analysis and regression analyses. The mean age of patients was 55, 98% were male, 58% Black, 8% Hispanic, and only 8% initiated buprenorphine within 12 months of OUD diagnosis. Four classes of co-occurring diagnoses were identified: "Few Co-occurring Diagnoses" (42.3%); "Multiple Pain Conditions" (21.3%); "Pain + SUD" (18.4%) and "Pain + SUD + Mental Health" (18.0%). Patients in the "Pain + SUD" class and "Pain + SUD + Mental Health" class were significantly less likely to initiate buprenorphine and had 59% and 45% lower odds, respectively, of initiating buprenorphine compared with patients in the "Few Co-occurring Diagnoses" class; this effect did not vary by HIV status. Buprenorphine retention was not significantly associated with HIV status or class membership. However, Black Veterans were less likely to initiate or be retained in buprenorphine treatment. Higher comorbidity burden was negatively associated with buprenorphine initiation but not with retention. More research is warranted to determine other factors that may influence treatment retention.