Sexual behaviour of heterosexual individuals with HIV infection naive for antiretroviral therapy in Italy

Background: Specific information about determinants of sexual behaviour of HIV infected heterosexuals, like injecting drug use (IDU), are essential to design interventions aimed at promoting safer sex practices. Methods: We analysed data on sexual behaviour collected, between March 1997 and March 1999, through a self administered questionnaire among 1050 IDUs and 642 non-IDU heterosexuals enrolled in a prospective multicentre cohort study on the natural history of HIV infection. Results: Among non-IDU heterosexuals, more women (48.5%) than men (25.1%) ( p<0.001) reported that they were infected by HIV positive regular partners whose HIV status they were not aware of. Among the 1119 heterosexual males, one fifth reported having had more than 25 sexual partners during their li fetime. Condom use in the last sexual intercourse was more common among het erosexual IDUs (64.9%) than among non-IDU heterosexual males (58.3%) (p=0.0 5). Heterosexual IDU males were more likely (66.7%) than non-IDU heterosexu als (50.6%) to have an HIV negative partner (p<0.001). Of the 573 heterosex ual females studied, 10.2% reported having had more than 25 lifetime sex pa rtners. This proportion was higher among heterosexual IDUs (18.8%) than amo ng non-IDU heterosexuals (4.3%) (p<0.001). Nearly 50% of the women in both groups reported having used a condom in the last intercourse. Almost 57% of heterosexual IDUs had a current HIV negative partner, compared with 34.9% non-IDU heterosexuals (p<0.001). In both sexes, the findings from univariat e analysis were confirmed by multiple logistic regression analysis. Conclusions: This study identified some important differences, in both male s and females, in sexual lifestyles according to injecting drug use (for ex ample, in terms of HIV negative partners). This observation indicates the n eed to tailor HIV prevention messages according to history of injecting dru g use.