INSIGHT INTO THE INFECTION DYNAMICS OF THE AIDS EPIDEMIC - A BIRTH COHORT ANALYSIS OF NEW-YORK-CITY AIDS MORTALITY

The authors analyzed the secular trends of New York City acquired immu nodeficiency syndrome (AIDS) mortality from 1980 through the first qua rter of 1991 using birth cohort techniques to provide insight into rea sons for temporal changes in growth of the epidemic. By disaggregating AIDS mortality data into composite birth cohorts, the authors determi ned that the slowing in the growth of the epidemic is a result of a le veling or decline in AIDS deaths in male birth cohorts born before 195 0 and a continued growth in younger male and all female birth cohorts. This phenomenon is believed to largely reflect earlier human immunode ficiency virus type 1 (HIV-1) infection patterns associated with age-r elated risk behaviors; however, to some lesser extent, it could also r eflect age-related host factors or therapies that may influence the ti me from HIV-1 infection to death. The findings support the hypothesis that the early infection dynamics of the epidemic were differentially related to age and sex, which resulted in a diffusion of infection fro m older to younger cohorts and from males to females over time. The fu ture growth of the epidemic will largely depend upon the infection pat terns of younger birth cohorts. This method of analyzing AIDS incidenc e or mortality data may contribute to a better understanding of earlie r patterns of HIV-1 infection within a defined population, which will be useful for targeting prevention efforts and improving AIDS forecast ing methods.