CHANGES IN AIDS SURVIVAL-TIME IN 2 SAN-FRANCISCO COHORTS OF HOMOSEXUAL MEN, 1983 TO 1993

Background.-During the first decade since the recognition of the acqui red immunodeficiency syndrome (AIDS), new therapies have been introduc ed and the frequency of clinical manifestations has changed. The impac t of these changes on AIDS survival, however, has not been well charac terized. Design.-A prospective cohort study of the outcomes of human i mmunodeficiency virus (HIV) infection. Setting.-Homosexual and bisexua l men residing in San Francisco, Calif, recruited in 1983 and 1984 for two prospective studies and followed up for more than 9 years with cl inical examinations. Participants.-A total of 761 HIV-positive homosex ual and bisexual men. MaIn Outcome Measures.-Survival time from a CD4 lymphocyte count at 0.20 x 10(9)/L (200/muL) and from a clinical AIDS diagnosis to death. Results.-Median survival time from a CD4 lymphocyt e count at 0.20 x 10(9)/L increased from 28.4 months in the October 19 83 to November 1986 period to 40.1 months in the November 1986 to Nove mber 1988 period and is estimated at 38.1 months in the November 1988 to February 1993 period. Patients diagnosed with Pneumocystis carinii pneumonia (PCP) accounted for most of this increase with a gain in med ian survival time of 9.7 months (P=.0009), compared with a nonsignific ant decline in the survival time of those patients without a PCP diagn osis. Multivariate analysis showed that rate of CD4 lymphocyte loss (P <.001) and receipt of both PCP prophylaxis and antiretroviral therapy (P=.04) were significantly associated with longer survival time, where as antiretroviral therapy alone was not (P=.81). Time to death from a clinical AIDS diagnosis was 14.7 months in the 1983 to 1986 period, 19 .1 months in the 1986 to 1988 period, and an estimated 15.7 months in the 1988 to 1993 period. Conclusions.-Survival time from a CD4 lymphoc yte count at 0.20 x 10(9)/L has improved significantly by about 1 year , yet survival time using the 1987 AIDS case definition has shown smal l improvement. The largest increase in survival time from a CD4 lympho cyte count at 0.20 x 10(9)/L was in patients diagnosed with PCP, sugge sting that PCP prophylaxis and treatment were more important factors i n longer survival time than antiretroviral therapy.