title: Evaluation of secular trends in CD4+ lymphocyte loss among human immunodeficiency virus type 1 (HIV-1)-infected men with known dates of seroconversion.
abstract: The rate at which immunodeficiency develops in untreated human immunodeficiency virus type 1(HIV-1)-infected persons might be increasing or decreasing over time because of viral evolution or other factors. Beginning in 1984, Multicenter AIDS Cohort Study investigators recruited HIV-1-seronegative homosexual/bisexual men from four US metropolitan areas and examined them semiannually for HIV-1 seroconversion. To assess possible secular changes in the natural history of HIV-1 infection, the authors examined CD4+ lymphocyte data from 354 men who seroconverted between 1984 and 1991. To control for measurement differences among centers and over time, the authors adjusted CD4+ lymphocyte values to those of persistently seronegative participants. CD4+ lymphocyte percentage measurements at the first seropositive visit formed a U-shaped pattern, with the lowest values observed in 1988 and 1989. The authors observed no consistent secular pattern of CD4+ percentages at later visit dates, except that mean CD4+ percentages were consistently lowest in men who seroconverted in 1988. In a proportional hazards model, the time to the adjusted CD4+ lymphocyte count of < 500 cells/mm3 was not associated with the secular time of seroconversion (relative hazard = 1.05, 95% confidence interval 0.97-1.13). The authors' data do not suggest a major change in the natural history of HIV-1 infection of this population.
authors.affiliation: Epidemiology and Biostatistics Program, National Cancer Institute, Public Health Service, US Department of Health and Human Services, Rockville, MD 20852, USA.
authors.forename: T R
authors.initials: TR
authors.lastname: O'Brien
authors.forename: D R
authors.initials: DR
authors.lastname: Hoover
authors.forename: P S
authors.initials: PS
authors.lastname: Rosenberg
authors.forename: B
authors.initials: B
authors.lastname: Chen
authors.forename: R
authors.initials: R
authors.lastname: Detels
authors.forename: L A
authors.initials: LA
authors.lastname: Kingsley
authors.forename: J
authors.initials: J
authors.lastname: Phair
authors.forename: A J
authors.initials: AJ
authors.lastname: Saah
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000209:etiology / Q000276:immunology*; D000328:Adult; D000704:Analysis of Variance; D001727:Bisexuality; D018791:CD4 Lymphocyte Count; D006679:HIV Seropositivity; D018451:Homosexuality, Male; D006801:Humans; D016014:Linear Models; D008297:Male; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D013997:Time Factors