Changing incidence of AIDS-defining illnesses in the era of antiretroviral combination therapy

Abstract

To determine the incidence of AIDS-defining opportunistic infections and malignancies over a 5-year period from 1992 to 1996. Subcohort of 1003 homosexual men with HIV infection and CD4 count less than 200 x 10(6) cells/l from the Frankfurt AIDS Cohort Study. Data including the earliest date that a CD4 T-lymphocyte count < 200 x 10(6)/l was reached and the dates of AIDS-defining events were compiled from medical records. Incidence analyses for AIDS-defining events and death during the subsequent 5 years (1992-1996) were performed using rates per 100 person-years of exposure. During the observation period, the number of patients per year with CD4 T-lymphocyte counts < 200 x 10(6)/l varied between 402 and 511. In 1992, 56.7% of patients experienced at least one AIDS-defining illness, and 20.7% in 1996. The annual number of AIDS-defining events per 100 patient-years of observation declined from 143.5 in 1992 to 38.3 in 1996, and the number of AIDS-related deaths fell from 25.7 to 12.9. Analysis of the number of events confirmed this trend for malignancies and single opportunistic infections, with the exception of mycobacterial diseases. The incidence of AIDS-defining events in patients with advanced HIV infection at Frankfurt University Hospital has declined by more than 70% from 1992 to 1996.