RESULTS

1. Sexual aggression and HIV risk behavior in heterosexual men Peterson, Z. D.1,2, Janssen, E.1, and Heiman, J. R. 1 1The Kinsey Institute for Research in Sex, Gender, and Reproduction, Indiana University 2Departments of Psychology and Women’s Studies, University of Missouri-St. Louis INTRODUCTION METHODS • Using an anonymous online questionnaire, we collected data from a sample of 1240 heterosexual men, ages 18 to 76 (mean age = 31). The questionnaire assessed the men’s demographic characteristics, alcohol use, sexual excitation (SES), sexual inhibition due to the threat of performance failure (SIS1), and sexual inhibition due to the threat of performance consequences (SIS2). We also measured participants’ history of sexual risk-taking and past perpetration of sexual aggression (see items below). • Items Measuring History of Sexual Aggression (adapted from Koss & Oros, 1982) • Have you ever engaged in sexual intercourse (penile-vaginal or penile-anal penetration) with someone who didn’t agree to… • …by using continual arguments and pressure to convince him or her? (Verbal Coercion) • …by using your position of authority (boss, teacher, camp counselor, supervisor) to make him or her? (Use of Authority) • …because he or she was too intoxicated from alcohol or drugs to say no? (Rape Through Intoxication) • …by threatening or using some degree of physical force (twisting his or her arm, holding him or her down, etc.) to make him or her? (Forcible Rape) • Have you ever attempted to engage in sexual intercourse (penile-vaginal or penile-anal penetration) with someone who didn’t agree to by threatening or using some degree of physical force (twisting his or her arm, holding him or her down, etc.), but intercourse did not occur? (Attempted Rape) • For each sexual aggression item that participants endorsed, they were asked to indicate how many times they had engaged in that behavior while wearing and not wearing a condom. Sexual behavior is a major pathway through which HIV/AIDS is transmitted, and heterosexual contact is the primary source of infection for heterosexual women. Thus, when heterosexual men perpetrate sexual aggression, it potentially places them and their unwilling female partners at risk for HIV and other STIs. In this study, we evaluated the relationship between sexual aggression and HIV risk at two levels: At the global level, we evaluated whether men who engage in sexual coercion or rape are more likely than other men to engage in other types of risky sexual behaviors (e.g., “one night stands” and unprotected sex). At the event level, we assessed the frequency with which specific incidents of sexual aggression are associated with unsafe sexual practices (i.e., a lack of condom use).We also attempted to identify factors that may be predictive of both sexual aggression and sexual HIV risk behaviors among heterosexual men. Figure 1: Two hypothesized levels of association between sexual aggression and sexual HIV risk behaviors. RESULTS Global Level Association Between Sexual Aggression and HIV Risk Behavior Predictors of Sexual Aggression and HIV Risk Behavior We conducted regression analyses with sexual aggression and sexual risk-taking variables as dependent variables. Age, number of sexual partners in the last year, alcohol use, SES, SIS1, and SIS2 were independent variables. For the logistic regression predicting sexual aggression, Wald (1, N = 1177) = 333.25, p < .001.a TABLE 1: Independent variables for logistic regression analysis predicting sexual aggression history Variable B SE Wald Age .02 .01 14.93*** Number of partners .04 .02 4.19* Alcohol per week .03 .01 14.37*** SES .02 .01 3.16 SIS1 .03 .01 5.88* SIS2 -.08 .02 21.71*** *p < .05; **p < .01; ***p < .001. For the regression predicting number of “one night stands,” F (6, 1163) = 24.57, p < .001.a,b TABLE 2: Independent variables for regression analysis predicting number of “one night stands” Variable B SE t Age .26 .04 6.79*** Number of partners .85 .09 8.99*** Alcohol per week .06 .06 1.05 SES -.01 .06 -0.19 SIS1 -.03 .08 -0.43 SIS2 -.32 .10 -3.09** *p < .05; **p < .01; ***p < .001. For the regression predicting number of partners with whom no condom was used, F (6, 1160) = 30.16, p < .001.a,c TABLE 3: Independent variables for regression analysis predicting number of unprotected partners Variable B SE t Age .00 .01 0.11 Number of partners .20 .02 10.97*** Alcohol per week .04 .01 3.58*** SES -.01 .01 -1.18 SIS1 .05 .01 3.52*** SIS2 -.07 .02 -3.95*** *p < .05; **p < .01; ***p < .001. aOne outlier on the alcohol measure was removed. bTwo outliers on the “one night stands” measure were removed. cTwo outliers on the partners without condoms measure were removed. Approximately 21% of our sample of men reported perpetrating at least one act of sexual aggression in their lifetime. After controlling for age, men who reported that they had perpetrated sexual aggression reported having had more sexual partners in the last year, more “one night stands,” and more partners in the last three years with whom they did not use a condom than men not reporting sexual aggression. Figure 2: Sexual risk-taking behaviors as a function of sexual aggression history Event Level Association Between Sexual Aggression and HIV Risk Behavior Many of the men who reported perpetrating sexual aggression indicated that they had done so multiple times. Of the total incidents of reported sexual aggression (n = 1583), nearly half (47%) were unprotected (i.e., no condom was worn). Figure 3: Condom use during individual incidents of sexual aggression. Percentages refer to percentage of total incidents of sexual aggression in which no condom was worn. SUMMARY AND CONCLUSIONS • In our anonymous online survey, over one fifth of men reported having obtained intercourse by using a coercive or aggressive sexual strategy. • Verbal coercion was the most commonly used strategy; however, a large number of participants also reported engaging in rape through intoxication. • Sexual aggression was associated with sexual risk-taking at a global level: Men who perpetrated sexual aggression engaged in more sexual risk-taking than non-aggressive men. • There also was evidence of an association between sexual aggression and HIV risk-taking at an event level: 47% of the incidents of sexual aggression were unprotected. • Future research could further investigate the event-level association between sexual aggression and HIV risk by conducting within-subject comparisons of rates of condom use during aggressive sex versus during consensual sex. • Consistent with prior research, these results suggest that alcohol use is an important risk factor for both sexual aggression and unprotected sex. • Our results also suggest that it may be beneficial to target men with low SIS2 for both sexual aggression and HIV/STI prevention interventions.