Objective: To evaluate the effect of transmission category and demographic, clinical and immunological characteristics on the progression to AIDS and survival of zidovudine-treated patients.
Design: Prospective multicentre cohort study of symptomatic non-AIDS patients.
Setting: Eighty-three clinical centres reporting data to the National Zidovudine Registry.
Patients: A total of 1468 patients enrolled between July 1987 and January 1991 were analysed.
Main outcome measures: Three-year AIDS-free survival probability estimates since therapy start. Cox proportional hazards regression analysis was used to identify independent predictors of progression to AIDS and survival.
Results: Faster progression was associated with increasing age (8% risk increase for a 5-year increase), low baseline CD4+ count (39% risk increase for 100 x 10(6)/l cells decrease), and zidovudine > 1000 mg/day (20% risk increase compared with < or = 1000 mg/day). Homosexual men had a 33% risk increase compared with other risk groups. The presence of fever and oral candidiasis at enrolment were also independently associated with a higher risk of progression. Differences in the risk of progression were not significant between men and women. Older age, baseline CD4+ count, homosexual behaviour, fever and oral candidiasis were independently associated with a shorter survival.
Conclusions: Our results confirm that age and baseline CD4+ count are independent predictors of progression, but do not provide evidence for differences in clinical outcome between the sexes. The higher risk of progression to AIDS and shorter survival for homosexual men appears to be correlated with the higher risk of developing Kaposi's sarcoma.