Gender differences in progression to AIDS and death from HIV seroconversion in a cohort of injecting drug users from 1986 to 2001

Abstract

Background: Although the consensus is that gender does not influence HIV progression, its relevance may depend on the setting.

Aim: To study gender differences in HIV progression to AIDS and death from 1986 to 2001 in a cohort of injecting drug user (IDU) seroconverters in Spain.

Methods: Risk of AIDS and death in persons infected for the same length of time were compared through Kaplan-Meier, allowing for late entry, and Cox regression adjusting for gender, age, and calendar period (before 1992, 1992-1995, 1996-1998, 1999-2001) fitted as time dependent covariates.

Results: Of 929 IDU, 24.7% were women. Median seroconversion year was 1993.3 for men and women. 44% of women and 34% of men received antiretroviral therapy. Risk of AIDS was lower in women in univariate (hazard ratio (HR) 0.72; 95%CI:0.51 to 1.01) and multivariate analyses (HR 0.73 95%CI:0.52 to 1.03). A 46% reduction in risk of AIDS for period 1999-2001 compared with 1992-1995 was seen in both men and women (HR: 0.56 (95%CI:0.36 to 0.87). As for mortality, women's risk of death was lower univariately (HR 0.67 95%CI:0.45 to 0.99) although compared with 1992-95, men experienced a 34% reduction in mortality during 1999-2001 (HR 0.66 95%CI:0.40 to 1.01), which was not statistically significant in women.

Conclusions: HIV progression was lower in female IDU before and after 1997 and their uptake of antiretroviral therapy was higher than male IDU. The inability to detect a reduction in mortality for women during 1999-2001 is probably attributable to lack of power. Differences in severity of addiction, drug using patterns, and competing causes of death may explain these findings.