Comparison of Kaposi sarcoma risk in HIV-positive adults across five continents: a multiregional multicohort study. Clinical Infectious Diseases
Bohlius et al. on behalf of the AIDS-defining Cancer Project Working Group in EuroCoord aimed to compare Kaposi sarcoma (KS) incidence rates in HIV-positive adults who started antiretroviral therapy (ART) across different continents, and to assess factors associated with regional differences in KS risk.
The authors included data on 208’140 patients from 42 cohorts in 57 countries across the Asia-Pacific, South Africa, Europe, Latin, and North America. Over the course of 1’066’572 person-years, 2’046 KS cases were diagnosed. The raw KS incidence rate per 100’000 person-years was highest in South Africa (280), followed by Latin America (244), North America (237), Europe (180), and the Asia-Pacific (52). After adjustment for current CD4 cell count, age at ART initiation, first-line regimen, and calendar year of ART initiation, risk was 5 times higher in South African women (adjusted HR [aHR] 4.56) than in their European counterparts, and 2 times higher in South African men. In Europe, Latin, and North America KS risk was 53% higher in heterosexual men than women (aHR 1.53), and 6 times higher in men who have sex with men (MSM) (aHR 5.95). Comparing patients with current CD4 cell counts ≥700 cells/μL with those whose counts were ≥700 cells/μL with those whose counts were
In conclusion, despite ART-related declines in KS incidence, men and women in South Africa and MSM remain at higher risk of KS than other HIV-positive persons, probably owing to higher human herpesvirus 8 (HHV-8) coinfection rates. While a vaccine against HHV-8 remains unavailable, early ART initiation and maintenance of high CD4 cell counts are essential to reducing the incidence of KS in populations at high risk for HHV-8 coinfection.