Death rates in HIV-positive antiretroviral-naive patients with CD4 count greater than 350 cells per microL in Europe and North America: a pooled cohort observational study.
BACKGROUND
Whether people living with HIV who have not received antiretroviral therapy (ART) and have high CD4 cell counts have higher mortality than the general population is unknown. We aimed to examine this by analysis of pooled data from industrialised countries.


METHODS
We merged data on demographics, CD4 cell counts, viral-load measurements, hepatitis C co-infection status, smoking status, date of death, and whether death was AIDS-related or not from 23 European and North American cohorts. We calculated standardised mortality ratios (SMRs) standardised by age, sex, and year, stratifying by risk group. Data were included for patients aged 20-59 years who had at least one CD4 count greater than 350 cells per microL while ART naive. All pre-ART CD4 counts greater than 350 cells per microL from January, 1990, to December, 2004, were included. We investigated mortality for four risk groups--men who have sex with men, heterosexual people, injecting drug users, and those at other or unknown risk. The association between CD4 cell count and death rate was investigated by use of Poisson regression methods.


RESULTS
Data were analysed for 40,830 patients contributing 80,682 person-years of follow-up. Of 419 deaths, 401 were used in the SMR analysis: 100 men who have sex with men (SMR 1.30, 95% CI 1.06-1.58); 68 heterosexual people (2.94, 2.28-3.73); 203 injecting drug users (9.37, 8.13-10.75); and 30 in the other or unknown risk category (4.57, 3.09-6.53). Compared with CD4 counts of 350-499 cells per microL, death rate was lower in patients with counts of 500-699 cells per microL (adjusted rate ratio 0.77, 95% CI 0.61-0.95) and counts of 700 cells per microL (0.66, 0.52-0.85).


CONCLUSIONS
In HIV-infected ART-naive patients with high CD4 cell counts, death rates were raised compared with the general population. In men who have sex with men this was modest, suggesting that a substantial proportion of the increased risk in other groups is due to confounding by other factors. Even though the increased risk is small, new studies of potential benefits of ART in this group are merited.


BACKGROUND
European Commission, FP6. European AIDS Treatment Network (NEAT). Project number LSHP-CT-2006-037570.
HIV Epidemiology and Biostatistics Group, Research Department of Infection and Population Health, UCL Medical School, Royal Free Campus, London, UK. r.lodwick@ucl.ac.uk
Lodwick
Rebecca K
RK
Sabin
Caroline A
CA
Porter
Kholoud
K
Ledergerber
Bruno
B
van Sighem
Ard
A
Cozzi-Lepri
Alessandro
A
Khaykin
Pavel
P
Mocroft
Amanda
A
Jacobson
Lisa
L
De Wit
Stephane
S
Obel
Niels
N
Castagna
Antonella
A
Wasmuth
Jan-Christian
JC
Gill
John
J
Klein
Marina B
MB
Gange
Stephen
S
Riera
Melchor
M
Mussini
Cristina
C
Gutiérrez
Félix
F
Touloumi
Giota
G
Carrieri
Patrizia
P
Guest
Jodie L
JL
Brockmeyer
Norbert H
NH
Phillips
Andrew N
AN
D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D044966:Anti-Retroviral Agents / Q000008:administration & dosage; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D005060:Europe / Q000453:epidemiology; D005260:Female; D006679:HIV Seropositivity / Q000150:complications / Q000188:drug therapy / Q000276:immunology* / Q000401:mortality*; D006526:Hepatitis C / Q000150:complications; D006801:Humans; D007391:International Cooperation; D008297:Male; D008875:Middle Aged; D009656:North America / Q000453:epidemiology; D016012:Poisson Distribution; D018570:Risk Assessment; D012307:Risk Factors; D019562:Viral Load
D019380:Anti-HIV Agents; D044966:Anti-Retroviral Agents