Effect of highly active antiretroviral therapy on diagnoses of sexually transmitted diseases in people with AIDS

Background There has been an increase in high-risk sexual behaviour and sex ually transmitted diseases (STD) during the time period when highly active antiretroviral therapy (HAART) became widely available. We examined whether taking HAART increased the risk of acquiring an STD-an epidemiological mar ker of unsafe sex-in people with AIDS. Methods We did a computerised match of people in the San Francisco STD and AIDS registries. People with AIDS who were diagnosed before 1999 and alive in November, 1995, or later, were classified as having had an STD after AID S diagnosis or not having had an STD after AIDS diagnosis. We used a Cox pr oportional hazards model to see whether use of antiretroviral therapy was a ssociated with acquiring an STD after AIDS, after adjustment for sex, age, race, HIV-1 risk category, and CD4 count at AIDS diagnosis. Findings People with AIDS who had had HAART showed an independent increase in the risk of developing an STD (hazard ratio 4.10; 95% CI 2.84-5.94). Ame ricans of African origin, younger age, and higher CD4 count at AIDS diagnos is were also associated with acquiring an STD after AIDS. The number of peo ple living with AIDS who acquired an STD increased over time from 60 (0.66% ) in 1995 to 113 (1.32%) in 1998 (p<0.001). Interpretation We have shown that people on HAART are more likely to develo p an STD, an epidemiological marker of unsafe sex. More intensive risk-redu ction counselling and STD screening for people with AIDS is needed.