Objective: To explore the impact of highly active antiretroviral therapy (HAART) on the prevention of AIDS-defining cancers relative to other AIDS-defining events.
Design: Prospective cohort study using 2,121 HIV+ male seroconverters (median age: 28 years, 51% white/non-Hispanic) in the Tri-Service AIDS Clinical Consortium (n = 1694) and the Multicenter AIDS Cohort Study (n = 427).
Methods: Poisson regression models, with calendar periods to represent antiretroviral therapy, were extended to analyze first incident AIDS-defining cancers and other first AIDS-defining events as competing risks.
Results: Eighty-one AIDS-defining cancers (64 Kaposi sarcomas; 17 non-Hodgkin lymphomas) and 343 other AIDS events occurred during 14,483 person-years in 1990-2006. The rate ratio of AIDS-defining cancers during the HAART calendar period was 0.26 (95% confidence limits: 0.15, 0.46) and of other AIDS-defining events was 0.28 (95% confidence limits: 0.21, 0.36) compared with the monotherapy/combination therapy calendar period, adjusting for age, infection duration, race, and cohort. The association of HAART with decreased AIDS incidence seemed to be equal (interaction ratio = 0.95 (95% confidence limits: 0.51, 1.74) for AIDS-defining cancers and other AIDS-defining events.
Conclusions: In human immunodeficiency virus-infected men, HAART seems equally protective against first AIDS-defining cancers and other first AIDS-defining events.