Gender difference in HIV RNA levels: a meta-analysis of published studies.

Plasma HIV RNA copy number is a strong prognostic marker of progression to AIDS in antiretroviral-naive persons. Recent research suggests women have lower HIV RNA levels than comparable men. Because clinical care recommendations currently include HIV RNA thresholds as a guide to initiating antiretroviral therapy (ART), the authors undertook the present quantitative meta-analysis to explore the relation between gender and plasma HIV RNA levels. A gender difference in HIV RNA levels was observed in the CD4-unadjusted and -adjusted analyses. The summary estimate including only CD4-adjusted results with the lowest heterogeneity indicated that on average, women have 41% lower plasma HIV RNA levels than men (-.23 log; 95% confidence interval [CI], -.16 to -.31 log ). Because numerous studies have found similar HIV disease progression rates in men and women, adjusted for CD4 but not HIV RNA, the present meta-analysis supports the use of lower HIV RNA thresholds in women than in men to guide initiation of ART. Given the patient characteristics in the original studies used in this meta-analysis, the results are most likely to apply to therapy-naive persons with CD4 lymphocyte counts >200 cells/mm, a subgroup for whom HIV RNA levels may strongly influence the decision to initiate therapy.