When to Start Antiretroviral Therapy? NA-ACCORD Stimulates the Debate

One of the most highly discussed and publicized HIV-related presentations at the recent Interscience Conference on Antimicrobial Agents and Chemotherapy/Infectious Diseases Society of America (ICAAC/IDSA) joint meeting was the study from the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD), a collaboration of 22 North American prospective clinical cohorts, examining the question of when to start therapy.1 The NA-ACCORD analysis presented by Kitahata and colleagues included more than 8000 patients (with almost 25,000 person-years of follow-up) who had CD4+ cell counts between 350/μL and 500/μL at a clinic visit between 1996 and 2006. The study compared all-cause mortality between those who started antiretroviral therapy within 1.5 years of their first CD4 count within that range (the "immediate" group) and those who did not start therapy within 1.5 years of reaching this CD4 threshold (the "deferred" group). The investigators found a 70% greater mortality in the deferred group (hazard ratio [HR] 1.7; P < .001), which was comparable to the effect of being 10 years older (HR 1.6; P < .001).