AIDS onset at high CD4⁺ cell levels is associated with high HIV load

To identify factors associated with development of AIDS at high CD4⁺ cell levels a nested case-control study using data from the Multicenter AIDS Cohort Study (MACS) was conducted. HIV-1-infected men who developed AIDS with ≥300/mm³ CD4⁺ cells (AIDS men) were compared to men who had ≥300/mm³ of CD4⁺ cells, but remained AIDS free for at least 2 years. The AIDS men had higher plasma HIV-1 RNA levels (mean 10^5.02 vs. 10^4.42, p < 0.01) and neopterin levels (mean 18.3 vs. 11.5 units/ml, p < 0.05) before the AIDS diagnosis than did the AIDS-free men. A significantly higher proportion of the AIDS men reported genital herpes within the year prior to their initial AIDS diagnosis than did the AIDS-free men (21.9 vs. 4.4%,p < 0.05). The higher viral load at relatively high CD4⁺ cell levels in men who subsequently developed AIDS within 6 months supports the hypothesis that elevated levels of HIV precede CD4⁺ decline and are the major factor in determining risk of AIDS even at high levels of CD4⁺ cell levels.