NATURAL-HISTORY OF ADVANCED HIV DISEASE IN PATIENTS TREATED WITH ZIDOVUDINE

Objective: To describe the natural history of advanced HIV disease in patients treated with zidovudine. Design: Longitudinal, observational study. Setting: Twelve academic and community-based sites. Patients, participants: Eight hundred and sixty-three patients with AIDS or AIDS-related complex (ARC) with a CD4+ lymphocyte count < 250 x 10(6)/l, who first received zidovudine between 15 April 1987 and 14 April 1988. Main outcome measures: Survival, progression to AIDS and first development of specific opportunistic illness. Results: Median survival after initiation of zidovudine therapy ranged from > 900 days in patients with a baseline CD4+ lymphocyte count greater-than-or-equal-to 150 x 10(6)/l to 560 days in patients with a CD4+ lymphocyte count < 50 x 10(6)/1. Other factors associated significantly with poorer survival were diagnosis of AIDS (versus ARC), baseline age greater-than-or-equal-to 40 years, hematocrit < 35%, and diminished functional status. In patients with ARC at enrollment, median time of progression to AIDS ranged from 810 days in patients with a CD4+ lymphocyte count greater-than-or-equal-to 150 x 10(6)/l to 310 days in patients with a CD4+ lymphocyte count < 50 x 10(6)/l. Rates of development of specific opportunistic infections or neoplasms and HIV encephalopathy were determined for different baseline CD4+ lymphocyte count ranges. Myelosuppression was significantly more common in patients with CD4+ lymphocyte counts greater-than-or-equal-to 100 x 10(6)/l. Sixty-five per cent of patients with a CD4 + lymphocyte count greater-than-or-equal-to 100 x 10(6)/l and 51% with a CD4+ lymphocyte count < 100 x 10(6)/l continued to receive zidovudine 2 years after starting therapy. Conclusions: We describe the natural history of a cohort of patients treated with zidovudine for advanced HIV disease. These CD4+ lymphocyte count-stratified estimates of disease progression should provide prognostic information useful in the clinical management of advanced disease and the design of future studies.