Challenges to sustained HIV care engagement after ED Re-linkage: The influence of substance use disorders.

Background: Emergency department (ED)-based HIV linkage-to-care programs effectively connect newly diagnosed people living with HIV (PLWH) to care and can also facilitate re-engagement among patients disengaged from HIV care. The linkage-to-care needs of these populations may differ substantially. We sought to identify factors associated with engagement outcomes following ED-based re-linkage to inform service delivery. Methods: This cross-sectional analysis used programmatic data from an ED-based HIV linkage-to-care program that served PLWH identified by automated electronic health record alerts to program staff upon ED presentation from January 2023 to July 2024. Patients were classified as not engaged in HIV care if, within the preceding three months, they had missed at least one HIV care appointment without rescheduling and had not refilled their antiretroviral therapy (ART). These individuals were approached at the bedside and offered re-linkage-to-care services. Among patients who received re-linkage-to-care services, the primary outcome was attendance at the scheduled HIV care appointment. ART refill within three months of the scheduled appointment was assessed descriptively. Associations between sociodemographic and clinical characteristics and appointment nonattendance were evaluated using univariate and multivariable logistic regression models. Results: Among 892 PLWH presenting to the ED, 113 (13%) were classified as not engaged in HIV care, of whom 66 (58%) received re-linkage-to-care services. All 66 patients who received re-linkage-to-care services had an HIV care appointment scheduled, and 40 (61%) attended their scheduled appointment. In adjusted analyses, patients with a history of substance use disorder had greater odds of appointment non-attendance (aOR=4.50, 95% CI 1.57-14.88; p = 0.03). All patients who attended subsequently refilled ART. Conclusions: A history of substance use disorder was associated with greater odds of HIV care appointment nonattendance following ED-based re-linkage-to-care services, highlighting the need for tailored substance use disorder informed strategies that address social, behavioral, and structural barriers to sustained HIV care engagement.