The association of immunosuppression and HIV control with Kaposi sarcoma among patients on antiretroviral therapy

Objective: Access to antiretroviral therapy (ART) has resulted in a decline in Kaposi sarcoma (KS) incidence among people with HIV (PWH). However, KS is still occurring among PWH receiving ART, and it is important to understand the degree to which risk of KS is impacted by response to ART. Methods: We examined the changing epidemiology of KS among >20,000 PWH receiving HIV care between 1996 and 2016 in the Center for AIDS Research Network of Integrated Clinical Systems (CNICS). We evaluated the association of KS with CD4 count and HIV viral load at ART initiation, within 6-12 months, and during clinical follow-up. Results: A total of 344 PWH were diagnosed with KS. CD4 count <200 cells/uL at ART initiation was associated with a >6-fold increased KS risk. Likewise, an HIV viral load >50,000 copies/mL at ART initiation was associated with a >3-fold increased KS risk. For every 100 cells/uL increase in CD4 count or log-unit decrease in HIV viral load during the 12-18 months after ART initiation, we observed 11% and 7% lower KS risks, respectively. During clinical follow-up after ART initiation, every 10% increase in time with a CD4 count >350 cells/uL or an HIV viral load <500 copies/mL was associated with 24% and 26% lower KS risks, respectively. All results reported here were statistically significant at the p < 0.05 threshold. Conclusion: KS risk among PWH receiving HIV care was significantly impacted by not only CD4 count and viral load at ART initiation, but also long-term suppression of HIV after ART initiation.