pre-ART immunosuppression was strongly associated with slower subsequent CD4 recovery in univariate analysis, the only independent predictor of slow recovery in multivariate models was CD4 nadir. Therefore, these data confirm the previous observation that the degree of CD4 depletion prior to ART initiation is the most consistent determinant of subsequent immune reconstitution, representing one of the first studies to confirm this in sub-Saharan Africa. These data also suggest that once a patient progresses to a certain level of CD4 depletion, it may not be as critical for how long they have been at that level, perhaps because at this point, substantial immunological damage has already occurred. Given recent studies showing that starting ART at higher CD4 counts ($350–500/ul) is both clinically advantageous and leads to improved immune constitution [17,18], the current data add to the growing body of knowledge that delaying ART may severely limit the clinical impact of therapy. Because delayed or lack of an immunological response to ART is multi-factorial [5], further investigations are needed to understand what influences better response to ART, to early on identify patients whose benefit from References 1. Bhaskaran K, Hamouda O, Sannes M, Boufassa F, Johnson AM, et al. (2008) Changes in the risk of death after HIV seroconversion compared with mortality in the general population. JAMA 300: 51–59. 2. Ledergerber B, Egger M, Erard V, Weber R, Hirschel B, et al. (1999) AIDS- related opportunistic illnesses occurring after initiation of potent antiretroviral therapy: the Swiss HIV Cohort Study. JAMA 282: 2220–2226. 3. Kaplan JE, Hanson D, Dworkin MS, Frederick T, Bertolli J, et al. (2000) Epidemiology of human immunodeficiency virus-associated opportunistic infections in the United States in the era of highly active antiretroviral therapy. Clin Infect Dis 30 Suppl 1: S5–14. 4. Miro JM, Lopez JC, Podzamczer D, Pena JM, Alberdi JC, et al. 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