Objective: To assess CD4+ cell count recovery in people severely immunosuppressed at start of antiretroviral therapy (ART) who achieve and maintain viral load suppression.
Methods: Eligible participants from the UK Collaborative HIV Cohort Study started ART with at least three drugs after 1 January 2000. Participants were required to have pre-ART CD4+ cell count below 100 cells/μl, at least 2 years of follow-up on ART, have achieved viral load suppression (≤50 copies/ml) by 9 months after starting ART and to have maintained this throughout follow-up. Participants were further required to be regularly engaged with care. We calculated the proportion of people who failed to achieve a CD4+ cell count of more than 100, 150, 200, 350 and 500 cells/μl by the time of the last follow-up, or 5 years from start of ART, whichever occurred first (censoring date).
Results: Of the 400 participants [median (interquartile range) pre-ART CD4+ cell count of 38 (14–65) cells/μl], 2 (0.5%), 8 (2%), 28 (7%), 131 (33%) and 259 (65%) failed to achieve a CD4+ cell count of more than 100, 150, 200, 350 and 500 cells/μl, by the censoring date, respectively. Kaplan–Meier estimates of the proportion of people reaching each CD4+ cell count threshold after 1 year on ART were 88, 70, 50, 14 and 3%, respectively, and after 3 years on ART, 98, 95, 90, 59 and 25%, respectively. Median (interquartile range) follow-up on ART was 3.9 (2.7–4.8) years.
Conclusion: Given a person with pre-ART CD4+ cell count below 100 cells/μl survives and maintains consistent viral load suppression on ART, there is over a 90% chance of reaching a CD4+ cell count above 200 cells/μl by 3 years.
aResearch Department of Infection & Population Health, UCL, London
bNorth Bristol NHS Trust, Bristol
cSt. George's Healthcare NHS Trust, London
dSouth Tees Hospitals NHS Foundation Trust, Middlesbrough
eBrighton and Sussex University Hospitals NHS Trust, Brighton
fNorth Middlesex University Hospital NHS Trust
gMortimer Market Centre, University College Medical School
hImperial College Healthcare NHS Trust
iHomerton University Hospital NHS Trust
jBarts and The London NHS Trust
kChelsea and Westminster Hospital NHS Foundation Trust
lSouth London Healthcare NHS Trust, London
mThe Lothian University Hospitals NHS Trust, Edinburgh
nUniversity Hospitals of Leicester NHS Trust, Leicester
oKings College Hospital NHS Foundation Trust, London, UK
pRoyal Free Hampstead NHS Trust, London, UK.
Correspondence to Jemma L. O’Connor, Research Department of Infection & Population Health, UCL Royal Free Campus, Rowland Hill Street, London NW3 2PF, UK. Tel: +44 207794 0500; internal 34684; fax: +44 207794 1224; e-mail: jemma.o’firstname.lastname@example.org
Received 30 September, 2013
Revised 21 November, 2013
Accepted 21 November, 2013