In multivariable logistic regression models, older age (per year increase, adjusted OR [aOR] 1.04, 95%CI 1.02–1.06), IVDU route of infection (versus heterosexual route, aOR 2.45, 95%CI 1.68–3.58) and pre-HAART CD4+ T-cell count (per 10 cells/μl increase, aOR 0.84, 95%CI 0.82–0.87) were significantly associated with INR after 1 year of treatment, after adjustment for each other and for gender, history of previous AIDS-defining events, calendar year at treatment initiation and type of HAART initiated. This evidence concerns the gene CD4 and AIDS.