Gender differences in heterosexual anal sex practices among woman and men in substance abuse treatment.

Heterosexual anal intercourse (HAI) is an understudied risk behavior among women and men in substance abuse treatment. In this ancillary investigation of data from two National Drug Abuse Treatment Clinical Trials Network (CTN) studies that evaluating gender-specific interventions for reducing HIV/STD risk behaviors for men/women in substance abuse treatment (protocols CTN-0018 and -0019), rates of HAI for women (n=441) and men (n=539) were identified for any, main, and casual partners. More men (32.8%) than women (27.1%) reported engaging in HAI in the previous 90 days. These rates are higher than those reported for both men (6-15,9%) and women (3.5-13%) ages 25-59 in the National Survey of Sexual Health and Behavior. Men were significantly more likely to report HAI with their casual partners (34.1%) than women (16.7%). In a logistic regression model generated to identify associations between HAI and variables previously shown to be related to high risk sexual behavior, being younger, bisexual, and white were significantly associated with HAI. For men, having more sex partners was also a significant correlate.

Conclusions: These data show that more substance abuse treatment-seeking women and men participate in HAI than in the general population and that condom use is low for both genders. Given that heterosexual transmission is a primary means of contracting HIV and the seroconversion risk is greatest for receptive AI, it is vital that any HIV prevention program include material on HAI.

Related protocols: CTN-0018, CTN-0019