Natural history of human immunodeficiency virus type 1 viremia after seroconversion and proximal to AIDS in a large cohort of homosexual men. Multicenter AIDS Cohort Study.

The natural history of human immunodeficiency virus type 1 (HIV-1) viremia and its association with clinical outcomes after seroconversion was characterized in a cohort of homosexual men. HIV-1 RNA was measured by reverse-transcription polymerase chain reaction (RT-PCR) in stored longitudinal plasma samples from 269 seroconverters. Subjects were generally antiretroviral drug naive for the first 3 years after seroconversion. The decline in CD4 lymphocyte counts was strongly associated with initial HIV RNA measurements. Both initial HIV RNA levels and slopes were associated with AIDS-free times. Median slopes were +0.18, +0.09, and -0.01 log10 copies/mL, respectively, for subjects developing AIDS <3, 3-7, and>7 years after seroconversion. In contrast, HIV RNA slopes in the 3 years preceding AIDS and HIV RNA levels at AIDS diagnosis showed little variation according to total AIDS-free time. HIV RNA load at the first HIV-seropositive visit ( approximately 3 months after seroconversion) was highly predictive of AIDS, and subsequent HIV RNA measurements showed even better prognostic discrimination.