Are There Gender and Race Differences in Cellular Immunity Patterns Over Age in Infected and Uninfected Children Born to HIV-Infected Women?

Abstract

This study investigated whether age-related patterns of immunologic markers in 1488 uninfected (9789 measurements) and 186 infected (3414 measurements) children differed by gender and race. CD4+, CD8+, and absolute lymphocytes by HIV infection status, gender, and race were assessed using linear mixed-effects natural cubic spline models, allowing for prematurity and maternal CD4+ cell count. In uninfected children, levels of all 3 markers peaked twice in the first few months of life, declining to adult levels by around 8 years of age; uninfected boys and uninfected black children had significantly reduced CD4+ and absolute lymphocyte counts; the gender difference was especially pronounced in black children. Infected children had substantially lower levels and distinctly different patterns; with, e.g., by age 6 months CD4+ cell counts nearly 1200 per mm3 lower than in uninfected infants. Levels also significantly differed by gender and race for infected children, although for gender in the opposite direction. The gender and race differences in CD4+ levels were not explained by a general lymphocytosis nor were they confounded by treatment. These substantial differences in immunologic markers may reflect underlying genetic influence on the cellular immune system and may have implications for clinical decisions about therapeutic management.