Syndemic of Substance Abuse, Depression, and Type 2 Diabetes and Their Association with Retention in Care Among People Living with HIV.

Substance abuse (SA), depression, and type 2 diabetes (DM2) often co-occur among people living with HIV (PLHIV). Guided by a syndemic framework, this cross-sectional retrospective study examined the cumulative and interaction effects of SA, depression, and DM2 on retention in HIV care (RIC) among 621 PLHIV receiving medical care in central Pennsylvania. We performed logistic regression analysis to test the associations between SA, depression, and DM2 and RIC. To test the "syndemic" model, we assessed additive and multiplicative interactions. In an unadjusted model, a dose-response pattern between the syndemic index (total number of health conditions) and RIC was detected (OR for 1 syndemic factor vs. none: 1.01, 95% CI: 0.69-1.47; 2 syndemic factors: 1.59, 0.89-2.84; 3 syndemic factors: 1.62, 0.44-5.94), but no group reached statistical significance. Interactions on both additive and multiplicative scales were not significant, demonstrating no syndemic effect of SA, depression, and DM2 on RIC among our study sample. Our findings highlight that comorbid conditions may, in some populations, facilitate RIC rather than act as barriers, which may be due to higher levels of engagement with medical care.