Gender and ethnic differences in survival in a cohort of HIV positive clients

Objectives: The purpose of this study was to examine gender and ethnic differences in survival of persons receiving treatment for HIV infection to determine if differences existed, and if they did, to assess the possibility of explaining these differences by examining other factors, such as age, disease severity when beginning treatment, alcohol, illicit drugs, tobacco, educational level, living arrangements, antiretroviral treatment, PCP prophylaxis, sexually transmitted diseases, mode of transmission and opportunistic infections. Design: A retrospective cohort study of all clients receiving treatment at an HIV only clinic from its opening in early 1988 until the end of May 1993. Statistical methods used to examine the data included incidence density ratios, Kaplan-Meier survival curves, Breslow (generalized Wilcoxon) tests of equality of survival curves and Cox proportional hazards models both with and without time dependent covariates. Results: In the cohort (37% African American, 7% Hispanic American and 25% female), 220 deaths occurred during 1223 person years of follow-up. Compared to European American males, the following incidence density ratios were observed: European American females: 0.50, Hispanic American females: 0.70, Hispanic American males: 0.96, African American females: 1.28 and African American males: 2.38. The differences were noted above for gender/ethnicity groups were significant at the p < 0.0001 level. After adjusting for disease stage (as measured by laboratory testing of CD4 positive T-lymphocytes), educational level, and age, no differences in survival by gender or ethnicity remained. Disease stage and educational level had the greatest prognostic significance. Conclusions: European Americans entered treatment at a much earlier disease stage (as measured by CD4 positive T-lymphocyte counts) and had higher educational levels (a surrogate for socioeconomic status) than African Americans. These factors may explain the longer survival in European Americans as compared to African Americans in this cohort.