CD4 cell eligibility thresholds: an analysis of the time to antiretroviral treatment in HIV-1 seroconverters

Minga, Albert Ka,b,c; Lewden, Charlottea,b,c; Gabillard, Delphineb,c; Bomisso, Germain Ia; Toni, Thomas-d'Aquina,d; Emième, Arlette Aa,d; Yapo, Vincenta,d; Inwoley, Andréa,d; Salamon, Rogera,b,c; Anglaret, Xaviera,b,c; for the Agence Nationale de Recherches sur le Sida (ANRS) 1220 Primo-CI Study Group

doi: 10.1097/QAD.0b013e32834625d3
Clinical Science: Concise Communications

Background: WHO recommends initiating combination antiretroviral treatment at the minimal CD4 cell threshold of 350 cells/μl. In sub-Saharan Africa, the time for a recently infected patient to reach this threshold is unclear.

Method: We estimated the probability of reaching different CD4 cell thresholds over time in the ANRS 1220 cohort of HIV-1 seroconverters in Côte d'Ivoire. CD4 cell slopes were estimated using a mixed linear model. Probabilities of crossing the 350 and 500 cells/μl CD4 cell thresholds were estimated by the Kaplan–Meier method.

Results: Between 1997 and 2009, 304 recent seroconverters have been enrolled in the Primo-CI cohort (62% men, median baseline age 29 years and median time since the estimated date of seroconversion 9 months). The probability of having a first CD4 cell count below 500 cells/μl was 0.57, 0.72, 0.79 and 0.84 at study entry, 2, 4 and 6 years, respectively. For a first CD4 cell count below 350 cells/μl, these figures were 0.29, 0.40, 0.55 and 0.67. The time for 75% of patients to reach the threshold was 3.0 years for 500 cells/μl and 7.0 years for 350 cells/μl.

Author Information

aProgramme PAC-CI, Abidjan, Côte d'Ivoire, France

bInserm U897, France

cUniversité Victor Segalen Bordeaux 2, ISPED, Bordeaux, France

dCeDReS Laboratory, University Hospital of Treichville, Abidjan, Côte d'Ivoire.

Received 8 December, 2010

Revised 4 February, 2011

Accepted 24 February, 2011

Correspondence to Dr Albert K. Minga, Programme PAC-CI, 18 BP 1954, Abidjan 18, Côte d'Ivoire. Tel: +225 21 355278/07 087661; fax: +225 21 355995; e-mail:

© 2011 Lippincott Williams & Wilkins, Inc.