Recent research studies have documented increases in sexual risk behaviors among men who have sex with men (MSM) both in the United States and abroad [1–7]. Although survey data have shown that a minority (typically from 20 to 30%) of HIV-positive MSM engage in sexual practices that place seronegative partners at risk of HIV infection [8–11], recent reports of increases in HIV incidence [12,13] and sexually transmitted infection (STI) rates [4,5,14,15] underscore the need to understand more fully the sexual behaviors of HIV-positive MSM. Clearly most HIV-positive gay and bisexual men neither want to nor intend to transmit HIV [16–18]; however, new infections continue to emerge among MSM, and in some areas of the United States diagnoses of HIV infection in this population have risen for three consecutive years from 2000 to 2003 .
Much of the discrepancy between the reported HIV risk reduction efforts of HIV-positive MSM and increasing rates of HIV infection may result from how sexual behaviors are assessed and what is perceived to constitute HIV transmission risk. For example, many of the initial studies to document the sexual risk behaviors of HIV-positive MSM did not assess the serostatus of sexual partners. Other studies assessed unprotected anal sex without consideration of whether the HIV-positive man was the insertive or the receptive partner, and few have assessed withdrawal before ejaculation. All of these factors can have an impact on the likelihood of HIV transmission [20,21].
Some have examined the strategies that gay and bisexual men use to enable them to obtain greater sexual satisfaction while reducing the risk of HIV transmission or infection. Many HIV-positive men choose to engage in unprotected sex with only, or primarily, other HIV-positive men [16–18]. The process of serosorting [18,22] is also used, by which individuals, regardless of their HIV status, engage in sexual risks only with those partners who they believe to be seroconcordant. Inherently problematic in this approach, however, is the potential for serosorting to fail. First, the approach assumes that HIV status disclosure has occurred; a recent study of HIV-positive gay and bisexual men found that 42% reported any sex (either protected or unprotected) without disclosing their status . Second, the approach assumes that individuals are fully honest and accurate regarding disclosure of their status, which is not always the case [24,25], and that they actually know their HIV status in the first place . Third, gay and bisexual men have been shown to make assumptions regarding the HIV status of their sexual partners, typically assuming that their partner's HIV status is concordant when engaging in unprotected sex [18,26,27]. These assumptions of seroconcordance are often made in sexual venues such as bathhouses and sex clubs, in which there is limited verbal communication, and MSM who frequent these venues have been found to be more likely to engage in unprotected sex [28,29]. As such, serosorting may reduce the risk of HIV transmission in some encounters, but questions remain about the effectiveness of this strategy in the light of serostatus disclosure and knowledge of serostatus among MSM.
Van de Ven and colleagues in Australia [30,31] discussed strategic positioning to address patterns of sexual risk-taking and risk management among gay and bisexual men. The underlying premise is that men have developed very clear understandings of HIV risks as well as differing levels of relative risk [21,22,32]. For example, despite the significant controversy and debate regarding the level of risk associated with oral sex resulting from conflicting empirical reports [33,34], gay and bisexual men understand the elevated risk of anal sex relative to oral sex [22,30,35,36]. Furthermore, these men tend to have a conceptualization of the relative risks of unprotected insertive versus receptive anal sex, in that they understand that HIV transmission and infection is more likely to occur if an HIV-positive man is the insertive partner and an HIV-negative man is the receptive partner during anal intercourse [22,37]. Such notions of strategic positioning to reduce the risk of HIV infection are supported by some epidemiological evidence [20,21,33,34].
Van de Ven et al.  found that of the 30% of gay men in serodiscordant relationships who reported unprotected anal sex, more than half engaged in strategic positioning, such that the HIV-negative men were insertive and the HIV-positive men were receptive. Furthermore, to ascertain whether or not this was indicative of intentional strategic positioning, rather than a preference for certain sexual positions, acts of protected anal sex in these serodiscordant relationships were examined. For protected sex acts, the majority of men, regardless of their HIV status, reported engaging in both insertive and receptive sex, lending support to the idea that such positioning for unprotected anal sex is strategic rather than preferential. Similar patterns of strategic positioning were identified for HIV-positive gay men with their serodiscordant casual sex partners.
A third harm reduction technique used by some gay and bisexual men is the practice of withdrawal before ejaculation during anal sex. Withdrawal may serve as a compromise between using condoms or not having anal sex, and the practice is commonly cited as a justification for having engaged in unprotected anal sex . Van de Ven et al.  found that 46% of the HIV-positive gay men reporting unprotected anal sex in a serodiscordant relationship engaged in consistent withdrawal. Although any unprotected anal sex, even that which includes withdrawal before ejaculation, represents a risk because of the presence of HIV in pre-ejaculatory fluid and the possibility that the insertive partner may not reliably withdraw [38,39], there is limited evidence from a study of heterosexual HIV transmission that such withdrawal does reduce the likelihood of HIV infection . There is substantial evidence, however, that gay and bisexual men perceive withdrawal to be a safer option than ejaculation [37,41,42], and that such men are engaged in the use of withdrawal as a harm reduction strategy for HIV prevention [21,42–44]. Some men, however, appear to use a resolve to withdraw as a justification for unprotected anal sex , and belief in the safety of withdrawal before ejaculation has been shown to predict HIV seroconversion .
Although condoms are recognized as providing the greatest protection in terms of HIV transmission, a minority of HIV-positive gay and bisexual men continue to engage in unprotected sex. However, HIV-positive men who engage in unprotected sex may attempt to minimize (but not eliminate) the risk of HIV transmission by having sex with other HIV-positive partners, taking the receptive role, or by withdrawal before ejaculation when taking the insertive role. In this paper, we focus on the sexual risk practices of HIV-positive gay and bisexual men in New York City and San Francisco, in order to understand these patterns of potential harm reduction strategies. Behaviors are examined separately for main and non-main partners, because studies have shown that gay and bisexual men within couples report higher frequencies of unprotected sex than single men [46,47]. Three specific hypotheses were tested: (i) HIV-positive gay and bisexual men would report behaviors consistent with serosorting, in terms of more sexual risk with other HIV-positive men than with HIV-negative or unknown-status partners; (ii) men would report strategic positioning, (more receptive rather than insertive sex with partners at risk); and (iii) men would report more acts of sex involving withdrawal before ejaculation than acts with ejaculation, with partners at risk.
The data reported here are based on the 1168 participants who completed the Seropositive Urban Men's Intervention Trial (SUMIT) baseline assessment. A detailed description of the methods is provided elsewhere in this issue .
Participants were asked to indicate race/ethnicity, date of birth, gender identification (i.e. male, transgender), sexual orientation (i.e. gay, bisexual, heterosexual, none of the above/unsure), educational background, employment status, personal income, partnership status (i.e. whether or not participants have a primary partner), and city of residence.
Sex behaviors were assessed by asking participants to indicate the frequency of four sexual behaviors (insertive oral, receptive oral, insertive anal, receptive anal) in the 3 months before completion of the survey, using a measure previously used with HIV-positive gay and bisexual men in the two cities . Participants reported their frequency of engaging in each sexual behavior with and without the use of condoms, with and without ejaculation (when condoms were not used), and separate frequencies were obtained for main partners (defined as ‘a partner you would call your boyfriend, spouse, significant other, or life partner’) and non-main (casual) partners. Furthermore, for non-main partners, participants reported sexual behavior frequencies for HIV-positive, HIV-negative, and unknown-status partners. For these frequencies, instructions were included such that participants responded to questions about HIV-positive and HIV-negative partners based on the number of non-main partners who told the participant their HIV status, or in the case of unknown non-main partners, partners who did not tell their HIV status or said that they did not know.
Open-ended frequency measures of sexual risk behaviors help to communicate expectations that such behaviors occur and are not abnormal, and as such have been recommended to improve the quality of self-report data [49,50]. Comparable measures of sexual risk practices used with gay men demonstrated that past 3 month assessment periods for sexual risk behaviors are reliable . The measures used in this study included easy to understand terminology, which was developed in conjunction with a Community Advisory Board of HIV-positive men.
The number of episodes for each sexual behavior were highly positively skewed, with the majority of men reporting no episodes. Because the non-normal distribution prohibits the use of typical parametric statistics (e.g. analysis of variance), we utilized non-parametric statistics, which do not require normally distributed data . Comparisons between three independent groups (e.g. comparisons of behaviors based on whether participants had a main partner who was HIV positive, HIV negative, or of unknown status) were conducted using the Kruskal–Wallis test for continuous variables (the non-parametric equivalent of a one-way analysis of variance) and chi-square tests for categorical variables. A number of the reported comparisons, however, are based on non-independent groups (e.g. a single participant could have both receptive and insertive sexual behaviors), and as such, require a separate set of non-parametric statistics. Comparisons of two non-independent groups were conducted using the Wilcoxon signed rank test for continuous variables and McNemar tests for categorical variables. For comparisons of three non-independent groups (e.g. comparison of men's behaviors with their HIV-positive, HIV-negative, and unknown-status non-main partners), comparisons were made using Friedman tests for continuous variables and Cochran's Q for categorical variables. Post-hoc comparisons between three independent groups were made using Mann–Whitney tests (for continuous variables) and chi-square tests (for categorical variables). Post-hoc comparisons between three non-independent groups were made with Wilcoxon signed rank tests (for continuous variables) and McNemar tests (for categorical variables). Confidence intervals presented include the lowest possible real value.
Of the 1168 men, 590 (50.5%) were from the New York City metropolitan area and 578 (49.5%) were from the San Francisco Bay area. Differences in sociodemographics and health characteristics between men in the two cities are presented elsewhere in this issue .
Overall, across the two cities, 17.8% of men (n = 151) reported having unprotected anal sex (either insertive or receptive) with a known HIV-negative non-main partner, but 34.0% (n = 288) reported unprotected anal sex with a non-main partner of unknown HIV status. When HIV-negative and unknown-status non-main partners were combined, representing potential HIV transmission risk, 47.3% of men (n = 390) reported any unprotected anal sex. When sex with main partners was examined across the two cities, 15.0% of men (n = 65) reported having unprotected anal sex (either insertive or receptive) with a known HIV-negative main partner, and 6.3% (n = 27) reported unprotected anal sex with a main partner of unknown HIV status. When HIV-negative and unknown-status main partners were combined, representing potential HIV transmission risk to main partners, 21.3% of men (n = 92) reported any unprotected anal sex.
When comparing unprotected sex among participants across the two cities, several significant differences were identified. Consistently, a greater percentage of men in San Francisco reported unprotected behaviors compared with men in New York, and men from New York typically reported lower frequencies of unprotected behaviors than men from San Francisco. Given the large number of significant differences between men from each city on sexual risk behaviors, men were analysed separately.
Sexual behaviors with main partners
Men from New York were significantly more likely to report a main sexual partner than men from San Francisco (42 versus 34%), χ2 (1) = 7.07, P < 0.01. In order to test the hypothesis that HIV-positive men with main partners at risk of HIV infection would report less sexual risk than men with HIV-positive main partners, comparisons were made across partner serostatus (see Table 1). Among men in both cities, those with HIV-negative or unknown-status main partners reported less insertive oral and anal sexual risk behaviors than those with HIV-positive main partners. However, no significant differences were identified for receptive oral and anal sex risk behaviors by main partner serostatus.
To examine strategic positioning, comparisons of insertive and receptive sex were made (see Table 2). The hypothesis was supported among men from San Francisco for both unprotected oral and anal sex behaviors, in that receptive sex was significantly more common than insertive sex. Among New York men, however, the hypothesis was supported for unprotected oral sex, but not for anal sex.
Finally, the hypothesis that men attempt to reduce the risk of transmission to their main sexual partners by selectively engaging in sexual risk behaviors without ejaculation (withdrawal) rather than with ejaculation was examined (see Table 3). The hypothesis was supported for oral sex but not for anal sex among men from both cities.
Sexual behaviors with non-main partners
Men in both cities reported significantly more non-main sexual partners whose serostatus was unknown to them, than either HIV-negative or HIV-positive partners (see Table 4). Men also reported more HIV-positive than HIV-negative non-main partners. The hypothesis that men would report serosorting with non-main partners, such that they engage in fewer unprotected behaviors with partners at risk of HIV infection was partly supported (see Table 4). On most sexual risk behaviors, men reported a greater prevalence and frequency of sexual risk practices with their HIV-positive non-main partners, compared with their HIV-negative non-main partners. However, contrary to the hypothesis, post-hoc comparisons indicated that men in both cities reported a greater prevalence and frequency of most sexual risk behaviors with serostatus-unknown non-main partners than with either HIV-positive or HIV-negative non-main partners.
In order to examine whether men attempted to reduce the sexual transmission risk to their non-main partners by using strategic positioning, comparisons in the reported prevalence and frequency of insertive behaviors relative to receptive behaviors were made (see Table 5). The hypothesis was supported among men from San Francisco, who were less likely to report and reported fewer unprotected insertive oral and anal sexual episodes (both in general and to ejaculation) with both their serostatus-unknown and HIV-negative non-main sexual partners (but no differences with their HIV-positive non-main partners). The hypothesis was supported among men from New York, but only among their non-main partners of unknown serostatus. In particular, men from New York were less likely to report and reported fewer unprotected insertive than receptive oral and anal sexual episodes with their unknown-serostatus non-main partners. Few differences were found between unprotected insertive and receptive sexual behaviors with their HIV-negative non-main partners, and no differences were found with HIV-positive non-main partners.
Finally, the hypothesis that HIV-positive men attempt to reduce the risk of transmission to their non-main sexual partners by selectively engaging in sexual risk behaviors without ejaculation (withdrawal) rather than with ejaculation was examined (see Table 6). The hypothesis was generally supported among both New York and San Francisco men. In particular, men from both cities reported fewer unprotected insertive and receptive oral episodes with ejaculation than without ejaculation with all partner types (HIV-positive, HIV-negative, and unknown), and reported fewer unprotected insertive anal episodes with ejaculation than without ejaculation with HIV-positive and unknown-status partners. Men in New York, however, did not demonstrate a significant difference in the number of acts of unprotected insertive anal sex with and without ejaculation with their HIV-negative non-main partners. Furthermore, no significant differences were noted in the number of unprotected receptive anal episodes that men reported with or without ejaculation, except that men from New York were more likely to report withdrawal during this behavior with their unknown-status partners.
We sought to obtain a better understanding of the patterns of sexual risk behaviors and harm reduction practices among HIV-positive gay and bisexual men in two HIV epicenters in the United States. The first finding of note concerns the fact that a number of HIV-positive men did report unprotected anal sex acts with partners at risk. Across the two cities, a total of 17.6% of the men in SUMIT reported any unprotected anal sex (either insertive or receptive) with known HIV-negative non-main partners and 15.0% with a known HIV-negative main partner. In addition, 33.6% of the men reported any unprotected anal sex with HIV status-unknown non-main partners, suggesting that the potential risk for HIV transmission among men in this sample (assuming some of these unknown-status partners are, in fact, HIV negative) is comparable to that found in other studies of HIV-positive gay and bisexual men [8–11,30]. It is important to note, however, that men in San Francisco were consistently more likely than men in New York to report having engaged in unprotected sexual activities.
Overall, the data provided support for the use of serosorting, strategic positioning, and withdrawal before ejaculation as harm reduction techniques. Across the two cities, men reported limited unprotected sex with HIV-negative partners compared with other partner types, more acts of sex as the receptive partner than the insertive partner, and more acts of unprotected anal and oral sex with withdrawal, rather than with ejaculation. The data thus generally support these patterns of harm reduction, and demonstrate that HIV-positive gay and bisexual men engage in sexual behaviors that are perceived to be lower risk for the transmission of HIV. However, many of the patterns of HIV harm reduction were inconsistent across specific sexual behaviors, across partner types, as well as across the two cities.
In both cities, men with HIV-positive main partners reported more unprotected sexual behaviors than men with HIV-negative or unknown-status main partners. In particular, the most risky behavior for HIV transmission, unprotected anal insertive sex with and without ejaculation, was less common with partners at risk of seroconversion, including partners of unknown status. However, these differences were not identified with regard to receptive anal sex (nor for receptive oral sex, a significantly less risky behavior). Therefore, for main partners, it appears that strategic positioning may function as a back-up strategy to serosorting in terms of reducing the likelihood of HIV transmission to partners at risk. For men in New York, however, strategic positioning was identified only with oral sex behaviors, and not for anal sex behaviors. It is unclear why HIV-positive men in San Francisco would be more likely to utilize strategic positioning with their main partners, whereas men in New York would not. It is possible that this finding emerged as a result of sampling differences, and the fact that non-representative samples of HIV-positive gay and bisexual men were enrolled. It is possible, however, that this difference is related to differential HIV risk reduction messages delivered in the two cities. It is also possible that the increased number of participants in New York who reported having a main partner is having an impact on this finding, or that the higher percentage of men with unknown-status main partners in New York resulted in these men making the assumption that their unknown-status main partner was actually HIV positive, decreasing their perceived need for strategic positioning. Finally, in terms of withdrawal before ejaculation with their main partners, men from both cities were significantly less likely to engage in oral sex with ejaculation than oral sex without ejaculation. However, there were no significant differences between the rates of anal sex with and without ejaculation.
In both cities, men reported more unprotected sex with their HIV-positive non-main partners than with their HIV-negative non-main partners, indicating some efforts at harm reduction via serosorting. However, men in both cities reported more unknown-status non-main partners than HIV-positive partners, and more sexual risk with these unknown-status partners than either their HIV-negative or their HIV-positive casual partners. This was true for both anal and oral sex behaviors, regardless of sexual positioning in terms of insertive and receptive, and regardless of whether or not withdrawal was practised. There was thus support for serosorting when the partner's serostatus was known, but this does not appear to be the case for partners of unknown status. This may be because of the common assumption that gay and bisexual men believe that partners with an unknown serostatus actually have a concordant serostatus . In addition, serosorting may be less common with unknown partners because of feelings of responsibility that emerge among some HIV-positive men, such that they believe that partners of unknown status who are willing to take risks must know the potential consequences and are thus making an informed decision to engage in sexual risk, which helps the HIV-positive man to distance himself from responsibility .
The hypothesis for strategic positioning with non-main partners was supported for men from San Francisco for both anal or oral sexual behaviors, and for both their HIV-negative and serostatus-unknown casual partners. For men in New York, the hypothesis was supported, but primarily for unknown-status partners. With known HIV-negative partners, the evidence for strategic positioning was less clear; although men reported more receptive anal and oral sex to ejaculation compared with insertive sex, there was no difference in general rates of anal and oral sex in terms of taking a receptive versus an insertive role with HIV-negative casual partners. The data from SUMIT corroborate work [21,32,37] show that HIV-positive men perceive a reduced risk from taking the receptive role during sexual risk behaviors. In both cities, there was no clear evidence of strategic positioning with HIV-positive casual partners, suggesting that men have fewer concerns about re-infection with a different strain of HIV than they do concerns about transmitting HIV to a casual partner. The differences in the patterns of sexual behavior with HIV-negative and HIV-positive partners lends additional support to the conclusion of Van de Ven et al.  that strategic positioning is an intentional and deliberate HIV-related harm reduction practice rather than merely a reflection of sexual position preferences.
The hypothesis for withdrawal as a harm reduction strategy for reducing the risk of HIV transmission to casual non-main partners was supported, overall, for both cities in terms of anal and oral sex behaviors, and was mostly true regardless of the HIV status of the partners. However, there was not support for this hypothesis among men in New York in terms of the number of acts of unprotected insertive anal sex with known HIV-negative partners. That is, men in New York, reported equivalent numbers of acts with and without ejaculation for this, the most risky of HIV transmission-related behaviors. It may be that when decisions have been made to engage in the most risky behavior for HIV transmission with known HIV-negative casual partners, the HIV-positive men (or their partners) do not feel that the added effort of withdrawal will significantly reduce risk. This may also help to explain why there were no significant differences in the number of acts of anal sex with and without ejaculation.
The fact that men in both cities reported more unprotected sex with unknown-status casual partners than with either their HIV-positive or their HIV-negative partners is a source of concern. Other researchers have found that HIV-positive gay and bisexual men reported increased sexual risk with other HIV-positive men rather than with men of unknown status [53,54]. It is likely that men in our sample are making assumptions about the serostatus of their unknown-status partners, probably assuming that they are HIV positive. These findings may also be indicative of the nature of sexual activities with partners of unknown status, in that these sex partners may be met in more ‘anonymous’ environments, such as public or commercial sex environments. Our previous work has shown that HIV-positive gay and bisexual men who report frequenting such venues for sex are more likely to report unprotected sex acts [28,29].
One of the primary problems with the use of serosorting and strategic positioning is the very real potential for the practice to be misguided. There is evidence that those in the seroconverting process are more infectious than those HIV-positive individuals who are asymptomatic . As such, for these men (many of whom will not know their HIV status), strategic positioning techniques may be both misguided (because the individual who perceives that he is HIV negative is actually HIV positive), and even behaviors designed to minimize risk (e.g. withdrawal) may still result in transmission as a result of increased infectiousness.
The evidence for strategic positioning suggests that messages about the differential risk of insertive versus receptive sex have been received by HIV-positive gay and bisexual men. It is unclear, however, the degree to which these men have accurate perceptions regarding the potential risks associated with unprotected receptive anal sex. For example, do these men feel that receptive anal sex is a ‘no risk’ behavior in terms of HIV transmission to sexual partners, or do they more accurately perceive it to be a risk behavior, but one less risky than unprotected insertive anal sex. Prevention messages and interventions need to highlight that receptive anal sex without the use of a condom can transmit HIV, but at the same time such messages may need to be tempered for fear of HIV-positive men increasing their unprotected insertive acts.
Similar concerns can be expressed regarding intervention efforts that would be designed to address withdrawal as a risk reduction practice. Like strategic positioning, withdrawal before ejaculation does not eliminate the risk of HIV transmission; however, the evidence that is currently available suggests that it can reduce the risk. HIV-positive gay and bisexual men need to understand that the potential reduced risk associated with withdrawal does not mean that there is the absence of risk. However, messages to communicate this point should take care to highlight the risk of withdrawal and receptive anal sex in ways that do not push men further away from harm reduction or cause them to give up on risk reduction in frustration. For example, Richters et al.  found that men who used withdrawal as a strategy were unlikely to use condoms at other times, indicating a strong motivation to avoid condoms. Intervention messages that are too strong regarding the risk of withdrawal could result in an individual who does engage in withdrawal increasing their acts of unprotected sex with ejaculation. Similarly, messages need to be tailored such that they do not have the effect of encouraging those who use condoms to believe that unprotected sex with withdrawal is acceptable.
It is important to recognize that in any one sexual relationship, or even in any single sexual encounter, men may employ multiple harm reduction strategies. This paper involved summing across all sexual behaviors, thereby missing potential situations in which more than one strategy is employed. Complicating this further, contextual variables (e.g. the use of alcohol or drugs, the location of sexual activity, the nature of the relationship, partner characteristics, the emotional condition of both parties at the time of having sex, etc.) are likely to impact the particular harm reduction strategies used in individual encounters. In our paper, we examined relationships across sexual encounters. In the real world, sexual behaviors among men are incredibly complicated and multilayered, such that a man who is high on methamphetamine in a bathhouse, having sex with an anonymous partner who is perceived to be incredibly attractive, is quite likely to employ different strategies than when he is sober, having sex in his own home with a partner he has had sex with before.
There are a number of important research and prevention implications. The days in which simple HIV prevention messages are widely accepted among gay and bisexual men appear to be over. Prevention efforts should address the complexities inherent in the sexual risk behaviors and harm reduction strategies of HIV-positive men, as well as the contextual factors that come into play. Men are clearly very advanced and sophisticated with regard to the complexity of their sexual activities and prevention behaviors, and our assessment tools need to mirror this. The complexity of the behavioral strategies that men have created to minimize HIV transmission suggests that it is simply insufficient to restrict the measurement of ‘high-risk sex’ as condomless sex. Timeline followback interviews and other techniques that capture the detailed aspects of sexual activity are necessary to understand more comprehensively and differentiate the relative risk of varied sexual behaviors. Finally, as randomized controlled trials of the effectiveness of harm reduction strategies compared with other strategies are neither feasible nor ethical, we can only rely on additional epidemiological investigations to continue to investigate harm reduction strategies. Gay and bisexual men are making decisions to use these strategies in the absence of complete data, and are empirically testing serosorting, strategic positioning, and withdrawal with their own bodies. Cohort studies would be helpful in examining, at least on some level, the efficacy of these strategies in order to obtain prevention data that can be used by HIV-positive and HIV-negative gay and bisexual men to minimize their risks. In consideration of the burdens inherent in cohort studies, case–control comparisons using serological tests for recent seroconversion could differentiate men who seroconvert despite having employed harm reduction strategies from men who think they might have seroconverted but did not.
The results presented should be examined in light of the fact that the data are both self-reported and cross-sectional. As a result, causal implications should not be inferred, and longitudinal studies are needed to determine causative relationships as well as the degree to which strategic positioning may change over time. Self-reported data are subject to response bias, and it is possible that some of the HIV-positive gay and bisexual men in our sample under-reported unprotected sex behaviors with known HIV-negative partners, because of social stigma issues. The use of Audio-CASI, however, tends to have a beneficial impact on the honesty of reporting sensitive and potentially stigmatized sexual behaviors [56,57]. It is also difficult to know how to interpret the higher rates of sexual risk and less utilization of harm reduction strategies with partners of unknown status, as these partners could have been HIV negative or HIV positive. It is also important to consider the broader generalizability of the data, as it was collected from two large urban HIV epicenters in the United States. It is possible that HIV-positive gay and bisexual men from other geographical areas may demonstrate different patterns of strategic positioning and harm reduction with regard to sexual risk taking. This is further evidenced by the city differences noted between New York and San Francisco in SUMIT.
Interventions aimed at HIV-positive gay and bisexual men need to recognize that such men are often utilizing harm reduction strategies, such as serosorting, strategic positioning, and withdrawal before ejaculation. Messages need to be carefully constructed so that men receive accurate information regarding the relative risk of various sexual risk practices, while at the same time making clear that ‘lower risk’ does not equal ‘low risk’ or ‘no risk’. Particular efforts should target men who engage in sexual risk practices with partners of unknown status, and it is likely that an increased focus on HIV testing and disclosure of one's status to sexual partners would have a minimizing effect on the number of unknown status partners. HIV-positive gay and bisexual men should be cautioned regarding making assumptions about the serostatus of their casual partners, as they may engage in inappropriate risk strategies based on inaccurate assumptions, resulting in the potential seroconversion of those partners who are, in fact, HIV negative.
The authors would like to thank Ron Stall and two reviewers for their helpful comments.
Sponsorship: This research was funded by the Centers for Disease Control and Prevention through cooperative agreements with New Jersey City University (UR3/CCU216471, J.T. Parsons, PI) and the University of California, San Francisco (UR3/CCU916470, C.A. Gomez, PI).
1. Chen SY, Gibson S, Weide D, McFarland W. Unprotected anal intercourse between potentially HIV
-serodiscordant men who have sex with men, San Francisco. J Acquir Immune Defic Syndr 2003; 33:166–170.
2. Stolte IG, Dukers NH, de Wit JB, Fennema JS, Coutinho RA. Increases in sexually transmitted infections among homosexual men in Amsterdam in relation to HAART. Sex Transm Dis 2001; 77:184–186.
3. Van de Ven P, Prestage G, Crawford J, Grulich A, Kippax S. Sexual risk behavior increases is associated with HIV
optimism among HIV
negative and HIV
men in Sydney over the Four-year period to February 2000. AIDS 2000; 14:2951–2953.
4. Centers for Disease Control and Prevention. Increases in unsafe sex and rectal gonorrhea among men who have sex with men – San Francisco, 1994–1997
5. Woltiski RJ, Valdiserri RO, Denning PH, Levine WC. Are we headed for a resurgence in the HIV
epidemic among men who have sex with men? Am J Public Health 2001; 91:883–888.
6. Ekstrand ML, Stall RD, Paul JP, Osmond DH, Coates TJ. Gay
men report high rates of unprotected sex with partners of unknown or discordant HIV
status. AIDS 2000; 13:1525–1533.
7. Dodds JP, Nardone A, Mercey DE, Johnson AM. Increase in high risk sexual behavior among homosexual men, London 1996–8. BMJ 2000; 320:1510–1511.
8. Darrow W, Webster R, Kurtz S, Buckley A, Stempel R. Impact of HIV
counseling and testing on HIV
-infected men who have sex with men. AIDS Behav 1998; 2:115–126.
9. de Vroome E, de Wit J, Stoebe W, Sandfort T, van Griensven G. Sexual behavior and depression among HIV
men. AIDS Behav 1998; 2:137–150.
10. Robins A, Dew M, Kingsley L, Becker J. Do homosexual men and bisexual
men who place others at potential risk for HIV
have unique psychological profiles. AIDS Educ Prevent 1997; 9:239–251.
11. Parsons JT, Halkitis PN, Wolitski RJ, Gómez CA. Correlates of sexual risk behaviors among HIV
-positive men who have sex with men. AIDS Educ Prevent 2003; 15:383–400.
12. Calzavara L, Burchell AN, Major C, Remis RS, Corey P, Myers T, et al
. Increases in HIV
incidence among men who have sex with men undergoing repeat diagnostic HIV
testing in Ontario, Canada. AIDS 2002; 16:1655–1661.
13. Kellogg T, McFarland W, Katz M. Recent increase in HIV
seroconversions among repeat anonymous testers in San Francisco. AIDS 1999; 13:2303–2304.
14. Centers for Disease Control and Prevention. Unrecognized HIV infection, risk behaviors, and perceptions of risk among young black men who have sex with men – six U.S. cities, 1994–1998
15. Fox KK, del Rio C, Holmes KK, Hook EW, Judson FN, Knapp JS, et al
. Gonorrhea in the HIV
era: A reversal in trends among men who have sex with men. Am J Public Health 2001; 91:959–964.
16. Halkitis PN, Parsons JT. Intentional unsafe sex (barebacking) among HIV seropositive gay
men who seek sexual partners on the internet. AIDS Care 2003; 15:367–378.
17. Wolitski RJ, Bailey CJ, O'Leary A, Gómez CA, Parsons JT. Self-perceived responsibility of HIV
+ MSM for preventing HIV
transmission to sex partners. AIDS Behav 2003; 7:363–372.
18. Suarez T, Miller J. Negotiating risks in context: a perspective on unprotected anal intercourse and barebacking among men who have sex with men – where do we go from here? Arch Sex Behav 2001; 30:287–300.
19. Valdisseri R. Preventing new HIV infections in the U.S.: what can we hope to achieve? Paper presented at the 10th Conference on Retroviruses and Opportunistic Infections
. Boston, MA, February 2003.
20. Vittinghoff E, Douglas J, Judson F. Per-contact risk of human immunodeficiency virus transmission between male sexual partners. Am J Epidemiol 1999; 150:1–6.
21. Wolitski RJ, Branson BM. Gray area behaviors and partner selection strategies. In: O'Leary A, editor. Beyond condoms: alternative approaches to HIV
prevention. New York: Kluwer/Plenum Press; 2002. pp. 173–198.
22. Suarez TP, Kelly JA, Pinkerton SD, Stevenson YL, Hyatt M, Smith MD, Ertl T. Influence of a partner's HIV
serostatus, use of highly active antiretroviral therapy, and viral load on perceptions of sexual risk behavior in a community sample of men who have sex with men. J Acquir Immune Defic Syndr 2001; 28:471–477.
23. Ciccarone DH, Kanouse DE, Collins RL, Miu A, Chen JL, Morton SC, Stall R. Sex without disclosure of positive HIV
serostatus in a US probability sample of persons receiving medical care for HIV
infection. Am J Public Health 2003; 93:949–954.
24. Wolitski RJ, Reitmeijer CAM, Goldbaum GM, Wilson RM. HIV
serostatus disclosures among gay
men in four American cities: general pattern and relation to sexual practices. AIDS Care 1998; 10:599–610.
25. Wulfert E, Safren SA, Brown I, Wan CK. Cognitive, behavioral, and personality correlates of HIV
-positive persons’ unsafe sexual behavior. J Appl Soc Psychol 1999; 29:223–244.
26. O'Leary A. Guessing games: sex partner serostatus assumptions in the SUMS. In: Halkitis PN, Gomez C, Wolitski R, editors. HIV
+ sex: the psychological and interpersonal dynamics of HIV
men's relationaships. Washington, DC: American Psychological Association; 2005. pp. 121–132.
27. Gold RS, Skinner MJ. Desire for unprotected intercourse preceding its occurrence: the case of young gay
men with an anonymous partner. Int J STD AIDS 1993; 4:326–329.
28. Parsons JT, Vicioso K. Brief encounters: the roles of public and commercial sex environments in the sexual lives of HIV
men. In: Halkitis PN, Gómez C, Wolitski R, editors. HIV
+ sex: the psychological and interpersonal dynamics of HIV
men's relationships. Washington, DC: American Psychological Association; 2005. pp. 183–200.
29. Halkitis PN, Parsons JT. Recreational drug use and HIV
-risk sexual behavior among men frequenting gay
social venues. J Gay
Lesbian Soc Serv 2002; 14:19–39.
30. Van de Ven P, Kippax S, Crawford J, Rawstorne P, Prestage G, Grulich A, et al
. In a minority of gay
men, sexual risk practice indicates strategic positioning for perceived risk reduction rather than unbridled sex. AIDS Care 2002; 14:471–480.
31. Kippax S, Race K. Sustaining safe practice: twenty years on. Soc Science Med 2003; 57:1–12.
32. Lowry E, Ross MW. It’ll never happen to me: gay
men's beliefs, perceptions and folk constructions of sexual risk. AIDS Educ Prevent 1994; 6:467–482.
33. Buchbinder SP, Douglas JM, McKirnan DJ, Judson FN, Katz MH, MacQueen KM. Feasibility of human immunodeficiency virus vaccine trials in homosexual men in the United States: risk behavior, seroincidence, and willingness to participate. J Infect Dis 1996; 174:954–961.
34. Page-Shafer K, Veugelers PJ, Moss AR, Strathdee S, Kaldor JM, Van Griensven GJ. Sexual risk behavior and risk factors for HIV
-1 seroconversion in homosexual men participating in the Tricontinental Seroconverter Study, 1982–1994. Am J Epidemiol 1997; 146:531–542.
35. Halkitis PN, Parsons JT. Oral sex and HIV
risk reduction: perceived risk, behaviors, and strategies among young HIV
men. J Psych Human Sex 1999; 11:1–24.
36. Kalichman SC, Cherry C, Williams EA, Abush-Kirsh T, Nachimson D, Schaper P, et al
. Oral sex anxiety, oral sexual behavior, and human immunodeficiency virus (HIV
) risk perceptions among gay
men. J Gay
Lesbian Med Assoc 1997; 1:161–168.
37. Gold RS, Skinner MJ. Gay
men's estimates of the likelihood of HIV
transmission in sexual behaviours. Int J STD AIDS 2001; 12:245–255.
38. Ilaria G, Jacobs JL, Polsky B, Koll B, Baron P, MacLow C, et al
. Detection of HIV
-1 DNA sequences in pre-ejaculatory fluid. Lancet 1992, 340: 1469.
39. Pudney J, Oneta M, Mayer K, Seage G, Anderson D. Pre-ejaculatory fluid as potential vector for sexual transmission of HIV
-1. Lancet 1992; 340:1470.
40. DeVincenzi I. A longitudinal study of human immunodeficiency virus transmission by heterosexual partners. N Engl J Med 1994; 331:341–346.
41. Quirk A, Rhodes T, Stimson GV. Unsafe protected sex: qualitative insights on measures of sexual risk. AIDS Care 1998; 10:105–114.
42. Richters J, Knox S, Crawford J, Kippax S. Condom use and withdrawal: exploring gay
men's practice of anal intercourse. Int J STD AIDS 2000; 11:96–104.
43. Parsons JT, Halkitis PN. Sexual and drug using practices of HIV
+ men who frequent commercial and public sex environments. AIDS Care 2002; 14:815–826.
44. Kippax S, Campbell D, Van de Ven P, Crawford J, Prestage G, Knox S, et al
. Cultures of sexual adventurism as markers of HIV
seroconversion: a case control study in a cohort of Sydney gay
men. AIDS Care 1998; 10:677–688.
45. Gold RS, Skinner MJ. Unprotected anal intercourse in gay
men: the resolution to withdraw before ejaculating. Psychol Rep 1997; 81:496–498.
46. Davidovich U, de Wit J, Albrecht N, Geskus R, Stroebe W, Coutinho R. Increase in the share of steady partners as a source of HIV
infection: a 17-yr study of seroconversion among gay
men. AIDS 2001; 15:1303–1308.
47. Hoff CC, Stall R, Paul J, Acree M, Daigle D, Phillips K, et al
. Differences in sexual behavior among HIV
Discordant and concordant gay
men in primary relationships. J Acquir Immune Defic Syndr 1997; 14:72–78.
48. Wolitski RJ, Parsons JT, Gómez CA, Purcell DW, Hoff CC, Halkitis PN, and the SUMIT Study Group. Prevention with gay
men living with HIV
: rationale and methods of the Seropositive
Urban Men's Intervention Trial (SUMIT). AIDS 2005; 19(suppl. 1):S1–S11.
49. Catania JA, Gibson DR, Chitwood DD, Coates TJ. Methodological problems in AIDS behavioral research: influences on measurement error and participation bias in studies of sexual behavior. Psychol Bull 1990; 108:339–362.
50. Weinhardt LS, Forsyth AD, Carey MP, Jaworski BC, Durant LE. Reliability and validity of self-report measures of HIV
-related sexual behavior: progress since 1990 and recommendations for research and practice. Arch Sex Behav 1998; 27:155–180.
51. Kauth MR, St Lawrence JS, Kelly JA. Reliability of retrospective assessments of sexual HIV
risk behavior: a comparison on biweekly, three month, and twelve month self-reports. AIDS Educ Prevent 1991; 3:207–214.
52. Gibbons JD. Nonparametric statistics: an introduction. Newbury Park
, CA: Sage; 1993.
53. Fisher JD, Willcutts DLK, Misovich SJ, Weinstein B. Dynamics of sexual risk behavior in HIV
-infected men who have sex with men. AIDS Behav 1998; 2:101–113.
54. Hoff CC, Stall R, Paul J. Differences in sexual behavior among HIV
discordant and concordant gay
men in primary relationships. J Acquir Immune Defic Syndr 1997; 14:72–78.
55. Leynaert B, Downs AM, De Vincenzi I. Heterosexual transmission of human immunodeficiency virus: variability of infectivity throughout the course of infection. Am J Epidemiol 1998; 148:88–96.
56. Gribble JN, Miller HG, Rogers SM, Turner CF. Interview mode and measurement of sexual behaviors: methodological issues. J Sex Res 1999; 36:16–24.
57. Turner CF, Ku L, Rogers SM, Lindberg LD, Pleck JH. Adolescent sexual behavior, drug use, and violence: Increased reporting with computer survey technology. Science 1998; 280:867–873.