Characterizing Indicators of Engagement in HIV-Associated Healthcare and Clinical Outcomes among People with HIV and Mpox in Washington, DC: A Nested Case-Control Study of the DC Cohort.

The high proportion of people with HIV (PWH) in the 2022-2023 mpox outbreak has raised questions surrounding the association between HIV and mpox. The objectives of this study were to evaluate the association between engagement in HIV-associated healthcare and mpox diagnosis, as well as to characterize cases of mpox among PWH. The DC Cohort is a longitudinal cohort of PWH in Washington, DC. We conducted a 5:1 (controls:cases) nested case-cohort study on male participants, matching age and care site. Cases were participants with an identified mpox diagnosis. Conditional logistic regression was used to assess the impact of indicators of engagement in HIV-associated healthcare on mpox diagnosis. We identified 70 cases of mpox in DC Cohort participants randomly matched to 323 controls, for a total of 393 participants included in the analysis. Study participants were primarily non-Hispanic Black (72.3%) with a median age of 41 (IQR: 36, 50). There was no association between engagement in care and mpox diagnosis; however, low CD4 was associated with increased odds of mpox diagnosis (aOR: 4.60 (95% CI: 1.23, 17.11)). Among a cohort of PWH, engagement in care was not associated with mpox diagnosis, suggesting that the overrepresentation of PWH among mpox cases is not due to surveillance bias.