Sex Differences In Hiv-1 Viral Load And Progression To Aids

EARLY REPORTS

Early reports

Sex differences in HIV-1 viral load and progression to AIDS
Homayoon Farzadegan, Donald R Hoover, Jacqueline Astemborski, Cynthia M Lyles, Joseph B Margolick,Richard B Markham, Thomas C Quinn, David Vlahov

Summary
Background Plasma HIV-1 RNA measurements are used for
initiation of antiretroviral treatments. Whether the viral-load
association withprognosis is similar in women and men is
unknown.
Methods We studied 812 specimens from 650 injection-drug
users (IDUs) participating in a continuous observational
study of patients based in a communityclinic. HIV-1 load
was measured by branched-chain DNA on samples from 527
IDUs from the baseline visit, and by reverse-transcriptase
PCR and quantitative microculture on samples from 285
IDUs at afollow-up visit 3 years later.
Findings Women had lower median viral-load measurements
than men by branched-chain DNA (3365 vs 8907
copies/mL; p=0·001), reverse-transcriptase PCR (45 416 vs
93130 copies/mL; p=0·02), and quantitative microculture
(5 vs 8 infectious units per million peripheral blood
mononuclear cells; p=0·015). This association remained
even after adjustment for CD4 cellcount, race, and drug use
within the previous 6 months. Time to AIDS was statistically
similar for men and women in a univariate proportionalhazards model and in a model adjusting for CD4 cell count.Proportional-hazards models showed that women with the
same viral load as men had a 1·6-fold higher risk of AIDS
(95% CI 1·10–2·32); or, equivalently, that women with half
the viral load of menhad a similar time to AIDS as men.
Interpretation Although a biological mechanism remains
unclear, these data suggest that current recommendations
for HIV-1 viral-load thresholds to initiateantiretroviral
therapy should be revised downwards for women.

Lancet 1998; 352: 1510–14

Introduction
On the basis of studies of predominantly white homosexual
men—which showed that quantity of...