RAPID AND SLOW DISEASE PROGRESSION IN HIV -1-INFECTED PERSONS IN MADRID, SPAIN

BACKGROUND: The rate of progression to AIDS in HIV-1 infected subjects is variable, and circumstances associated with more rapid or slow dev elopment of severe immunodeficiency might be grouped in three categori es: environmental cofactors, host features, and particular virulence o f the virus itself. Currently, it is not yet clear the relative impact of each one. PATIENTS AND METHODS: A cross-sectional study was done i n a cohort of 1,783 IV-1 infected persons from three centers located i n Madrid, mainly devoted to attend persons at risk for HIV infection. Long-term nonprogressors (LTNP) were defined as those with more than 8 years of confirmed HIV seropositivity, and CD4+ T-cell count above 50 0 x 10(6)/l in the absence of antiretroviral therapy or symptoms sugge sting immunodeficiency. Rapid progressors (RP) were those with less ta n 5 years from seroconversion and repeatedly current CD4+ T-cell count below 200 x 10(6)/l. An analysis of different epidemiological, immuno logical and virological features was performed comparing LTNP and RP. RESULTS: Among 1,783 HIV (+) subjects studied, 100 (5.6%) fulfilled cr iteria for LTNP and 12 (0.7%) for RP. Among LTNP, stabilized CD4 slope was seen in 16 (33%) out of 48 after more than 8 years of infection, Variables statistically associated with LTNP were: past history of int ravenous drug addiction (80% of them), male gender (79% of them), high alcohol intake (48% of them), HIV-1 non-syncitium inducing viral phen otype, and very low or undetectable HIV-1 plasma viremia. In contrast, variables associated with RP were: infection by sexual contact (75% o f cases), female gender (50% of them), syncitium-inducing viral plenot ype, and high titers of plasma viremia. The CD4/CD8 ratio below 1 was seen in all RP and in 88% of LTNP. However, a preferent depletion of C D4+ cell occurred in the first group, instead of an enhancement of the CD8 T-cell count in LTNP, The prevalence of serological markers for h epatotropic viruses and other potential infectious cofactors was not h igher in RP. CONCLUSIONS: Multiple factors seems to account for the di fferent rate of disease progression observed in HIV-1 infected persons . The dynamic equilibrium between the immune system and the virulence of the virus seem to be influenced -but not determined- by environment al infectious or non infectious cofactors.