520   Late Initiation of Antiretroviral Therapy (at CD4⁺Lymphocyte Count <200 Cells/mL) Is Associated with Increased Risk of Death.

J. Kaplan*¹, D. Hanson¹, J. Karon¹, D. Cohn², M. Thompson³, S. Buskin⁴, P. Fleming¹, and M. Dworkin¹.
¹CDC, Atlanta, GA;²Denver Dept. of Hlth. and Hosp., CO;³AIDS Res. Consortium of Atlanta, GA; and⁴Publ. Hlth.-Seattle & King County, WA.

Background:When to start antiretroviral therapy (ART) is one of the most important questions facing HIV clinicians in industrialized nations.

Methods:We assessed the risk of HIV-related death among 5,110 persons starting 2- or 3-drug antiretroviral therapy (ART) in 1994 or later in CDC's Adult and Adolescent Spectrum of Disease Project, a medical record review surveillance project conducted in 11 U.S. cities. Risk was assessed as a function of CD4+ lymphocyte count at time of initiation of ART (lowest count <12 months before initiation) and other variables potentially associated with clinical outcome (age, sex, race, HIV exposure mode, history of AIDS illness, 2- vs. 3-drug therapy) in a Cox proportional hazards model.

Results:

Conclusions:The increased risk of death associated with late initiation of ART (at CD4+ <200/mL) indicates that ART should be initiated at higher CD4+ levels. The increased HRs associated with CD4+ counts between

200 and 349/mL were more modest, and their statistical nonsignificance indicates uncertainty as to the optimal CD4+ count at which ART should be initiated.