Importance of Baseline Prognostic Factors With Increasing Time Since Initiation of Highly Active Antiretroviral Therapy: Collaborative Analysis of Cohorts of HIV-1-Infected Patients

Antiretroviral Therapy Cohort Collaboration

JAIDS Journal of Acquired Immune Deficiency Syndromes: 15 December 2007 - Volume 46 - Issue 5 - pp 607-615
doi: 10.1097/QAI.0b013e31815b7dba
Epidemiology and Social Science

Background: The extent to which the prognosis for AIDS and death of patients initiating highly active antiretroviral therapy (HAART) continues to be affected by their characteristics at the time of initiation (baseline) is unclear.

Methods: We analyzed data on 20,379 treatment-naive HIV-1-infected adults who started HAART in 1 of 12 cohort studies in Europe and North America (61,798 person-years of follow-up, 1844 AIDS events, and 1005 deaths).

Results: Although baseline CD4 cell count became less prognostic with time, individuals with a baseline CD4 count <25 cells/μL had persistently higher progression rates than individuals with a baseline CD4 count >350 cells/μL (hazard ratio for AIDS = 2.3, 95% confidence interval [CI]: 1.0 to 2.3; mortality hazard ratio = 2.5, 95% CI: 1.2 to 5.5, 4 to 6 years after starting HAART). Rates of AIDS were persistently higher in individuals who had experienced an AIDS event before starting HAART. Individuals with presumed transmission by means of injection drug use experienced substantially higher rates of AIDS and death than other individuals throughout follow-up (AIDS hazard ratio = 1.6, 95% CI: 0.8 to 3.0; mortality hazard ratio = 3.5, 95% CI: 2.2 to 5.5, 4 to 6 years after starting HAART).

Conclusions: Compared with other patient groups, injection drug users and patients with advanced immunodeficiency at baseline experience substantially increased rates of AIDS and death up to 6 years after starting HAART.

Received for publication April 30, 2007; accepted September 18, 2007.

The Antiretroviral Therapy Cohort Collaboration is supported by UK Medical Research Council grant number G0100221. Sources of funding of individual cohorts include the Agence Nationale de la Recherche sur SIDA et le hepatitis virale CO3 and CO4; the Institut National de la Santé et de la Recherche Médicale; the French, Italian, and Swiss Ministries of Health; the Stichting HIV Monitoring; the European Commission; the British Columbia and Alberta Governments; the Michael Smith Foundation for Health Research; the Canadian Institutes of Health Research; and unrestricted grants from GlaxoSmithKline, Roche, and Boehringer-Ingelheim.

*See Appendix for Writing Committee and members of study group.

Correspondence to: Jonathan A. C. Sterne, MA, MSc, PhD, Department of Social Medicine, University of Bristol, Canynge Hall, Whiteladies Road, Bristol, BS8 2PR UK (e-mail:

© 2007 Lippincott Williams & Wilkins, Inc.