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Australian Gay Men Who Have Taken Nonoccupational Postexposure Prophylaxis for HIV Are in Need of Effective HIV Prevention Methods

Zablotska, Iryna B. PhD*; Prestage, Garrett PhD*; Holt, Martin PhD; Poynten, Mary PhD*; de Wit, John PhD; Guy, Rebecca PhD; Mao, Limin PhD; McAllister, John RN; Grulich, Andrew E. PhD*

JAIDS Journal of Acquired Immune Deficiency Syndromes: December 1st, 2011 - Volume 58 - Issue 4 - p 424–428
doi: 10.1097/QAI.0b013e318230e885
Epidemiology and Prevention

Background Gay men who request nonoccupational postexposure prophylaxis (PEP) may seek preexposure prophylaxis (PrEP) should this become available. We explored trends and predictors of PEP use among Australian gay men to inform future biomedical prevention programs.

Methods We used 2001–2010 data from Gay Community Periodic Surveys in 3 Eastern Australian states and assessed PEP awareness and use in the 6 months before each survey, and among HIV-uninfected men in all surveys predictors of PEP use. Analytical methods included chi-square test for trend and multivariate log-binomial estimation of associations.

Results The awareness of PEP significantly increased from 23% in 2001 to 64% in 2010. PEP use also increased from 2.3% to 3.9%, respectively. PEP use was significantly associated with being in a regular relationship with an HIV-serodiscordant partner, higher number of sex partners, engaging in anal intercourse with casual partners, and regularly testing for HIV/sexually transmitted infections. However, fewer than 8% of men who engaged in these practices reported PEP use.

Conclusions Our findings highlight the profiles of current PEP users: men in HIV-serodiscordant relationships, and men having high numbers of casual partners and unprotected anal intercourse with them. These men are in need of effective HIV prevention strategies and may be receptive to preexposure prophylaxis in the future. Presently, targeted HIV education to improve risk assessment skills may prevent some seroconversions through the appropriate use of PEP.

*Kirby Institute

National Centre in HIV Social Research, The University of New South Wales, Sydney, Australia 2010

St. Vincent's Hospital, Sydney, Australia 2010.

Supported by the Australian Government Department of Health and Ageing. The Australian Gay Community Periodic Surveys are funded by the state Health Departments in New South Wales, Victoria, Queensland, South Australia, Western Australia, and the Australian Capital Territory where surveys are conducted. The Kirby Institute (formerly National Centre in HIV Epidemiology and Clinical Research) and the National Centre in HIV Social Research are funded by the Australian Government Department of Health and Ageing. The views expressed in this publication do not necessarily represent the position of the Australian Government.

Author Contributions: I. Zablotska formulated the research issue and assumed principal responsibility for the design of this analysis and preparation of the article. I. Zablotska, A. Grulich, G. Prestage, and M. Holt contributed to the design of the behavioral surveillance surveys, data collection, and interpretation. All authors took part in interpretation of the results and assisted with the preparation of this article.

The authors have no conflicts of interest to disclose.

Correspondence to: Iryna Zablotska, PhD, The Kirby Institute, The University of New South Wales, Sydney 2010, Australia (e-mail:

Received June 10, 2011

Accepted August 1, 2011

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Postexposure prophylaxis of HIV (PEP) with antiretrovirals (ARV) is now the standard of care in Australia,1,2 United States,3 and other developed countries.4 For nonoccupational exposures, PEP has been available nationally in Australia since 1999.5 Education about the availability of PEP has been part of health promotion among gay men since then.6

PEP effectiveness depends on the ability of people to correctly identify high HIV risk exposure events,7 the time since exposure to initiation of therapy,8 adherence to the prescribed regimen, and continued risk behavior for HIV acquisition during and after PEP.9 For these reasons, PEP has limited potential for a public health impact on the HIV epidemic among gay men.10

Interest in the use of ARVs as a public health intervention for HIV prevention in gay men has been reignited by a recent report that HIV risk was reduced by 44% with ARVs used as preexposure prophylaxis (PrEP).11 So far, very low levels of PrEP use have been reported among homosexual men in the United States,12–15 and a study conducted in the mid-2000s suggested virtually no use in Australian gay men.16 Nevertheless, gay men who use PEP, particularly recurrent users, acknowledge HIV risk exposures. They are in need of effective HIV prevention strategies. These men may see a benefit of using ARVs as prevention and may seek PrEP should it become available. In this article, we investigate trends and predictors of PEP use in Australian gay men. This is likely to strongly resemble the profile of potential future users of PrEP.

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Population and Sample

We used data from the ongoing Australian HIV behavioral surveillance—the Gay Community Periodic Surveys. The methodology of data collection has been described previously.17 Briefly, Gay Community Periodic Surveys are conducted in major cities of 6 Australian states/territories: New South Wales, Victoria, Queensland, South Australia, Western Australia, and the Australian Capital Territory. The surveys employ convenience time–location sampling and recruit gay men from gay community venues, events, and clinics. Response rates range between 65% and 85%.

The largest gay communities in Australia are located in the Eastern Australian states (New South Wales, Victoria, and Queensland), where surveys have been conducted annually. In this analysis, we used all available data from 2001 (when data collection about PEP started) until the end of 2010.

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Survey Content and Measures

A brief self-administered questionnaire included questions on demographics, sexual identity, HIV, and sexually transmitted infection (STI) testing in the past 12 months, sexual relationships, and sexual practices with regular and casual partners in the past 6 months before the survey.

We focused on 2 main questions: (1) “What do you know about PEP?” (“It is readily available now,” “It will be available in the future,” and “I have never heard about it”; data available for all years except 2005) and “Have you received PEP in the past 6 months?” (“Yes” vs. “No”; data not collected in 2005–2006 and 2010).

We evaluated sociodemographic predictors and sexual and testing practices of PEP users. Selected sociodemographic predictors included age, completed level of education, ethnic background, and residential location. To assess whether PEP awareness and use are higher among men in HIV-serodiscordant regular relationships with other men, we also assessed the seroconcordance status of regular relationships (“Seroconcordant, both partners HIV negative,” “Serodiscordant,” and “Not concordant, at least one partner's status not known”).

The indicators of sexual practices included number of sex partners in the past 6 months, any unprotected anal intercourse with regular partners or with casual partners (UAIC). The latter 2 indicators were constructed as described previously,18 and were based on 2 blocks of identical questions about sexual practices with regular and casual partners. All sexual practices were assessed relating to the 6 months preceding the survey.

We also explored HIV and STI testing practices such as having been tested for HIV in 12 months before the survey (among men who were not HIV positive) and having been tested for STIs other than HIV in the 12 months before the survey.

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Data Analyses

PEP use was assessed among men at risk for HIV; therefore, HIV-positive respondents were excluded. Trends were evaluated using the chi-square test for trend. For the analyses of associations, we used Pearson's chi-square test with Type I error of 5% and log-binomial regression models as appropriate. We present prevalence rate ratios (PRR) and 95% confidence intervals (95% CI) adjusted for the state and year of survey. All analyses were executed in STATA 10.0 (StataCorp, College Station, TX).

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The awareness of PEP availability among gay men increased from 23% in 2001 to 64% in 2010 (P trend < 0.001) (Fig. 1). The prevalence of PEP use in the last 6 months before the survey also increased during this time from 2.3% to 3.9% (Fig. 2). PEP use was significantly more likely if men were aware about its current availability compared with those not aware (adjusted PRR = 1.63; 95% CI: 1.49 to 1.78). In 2009–2010, there was no significant difference in PEP awareness or use across the Eastern Australian states.





The proportion of men who reported taking PEP in the last 6 months gradually declined with age (Table 1). A significantly higher proportion of young men aged below 30 years had taken PEP compared with the next age group of men in their 30s. Otherwise, sociodemographic characteristics other than age were not significantly associated with the use of PEP, but high-risk sexual practices were.



Among men in regular relationships (data not presented in Table 1), PEP use was higher among those with serodiscordant regular partners (6.1%) compared with men in seroconcordant HIV-negative relationships (3.0%) or men in nonconcordant relationships (3.9%) (P < 0.001). However, in all regular relationships, PEP use did not depend on condom use. In this sample, 157 men reported being in a serodiscordant relationship and having had unprotected anal intercourse with their serodiscordant regular partners in the 6 months preceding the survey; only 9% of these men had taken PEP in the 6 months before the survey despite being aware about it.

PEP use was also associated with the number of casual sex partners in the past 6 months, particularly 11 or more partners (adjusted PRR = 1.43; 95% CI: 1.15 to 1.76), and with engaging in UAIC (adjusted PRR = 1.22; 95% CI: 1.07 to 1.39). Of the 3591 men (19% of our sample) who reported unprotected anal intercourse with casual partners, only 6% had taken PEP in the last 6 months. Among men who reported no UAIC, 3.9% reported PEP use. The prevalence of PEP use in the last 6 months was higher (8.7%) in men who had UAIC who were aware of PEP availability. We did not have information about serostatus of casual partners to further investigate PEP use by risk exposure. There was also a significant positive association between PEP use and testing for HIV (adjusted PRR = 1.70; 95% CI: 1.43 to 2.02) or STI (adjusted PRR = 1.51; 95% CI: 1.21 to 1.90).

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Our analysis of behavioral surveillance data produced 3 important findings about PEP use. First, in Australian gay communities the level of awareness about PEP availability is high, but still not universal. Second, the prevalence of PEP is not negligible and has doubled during the last decade. The work of gay community organizations to inform and educate gay men about PEP has contributed to this increase,6 but PEP has continued to be used in only a small minority of high-risk events. Finally, there seem to be at least 2 distinctive categories of gay men who are aware of and are using PEP, specifically men in serodiscordant relationships and men having high number of casual partners and engaging in unprotected anal intercourse with them. Because of the practices they engage in, these men may be at high risk for HIV and may be more receptive to new biomedical prevention technologies when these become accessible.

Gay men younger than 30 reported lower levels of PEP awareness but higher levels of PEP use compared with older age groups. Compared with older men, they may have poor knowledge about HIV risk factors and prevention methods and may be less confident in risk assessment.19 Furthermore, PEP awareness does not necessarily equate to PEP literacy. Targeted education about risk assessment among these men not only can prevent some HIV infections but may also decrease anxiety about HIV among some men who request PEP.

Our analyses showed that most men, who had had unprotected anal intercourse (either with serodiscordant regular partners or with casual partners), were aware about PEP but did not take PEP. Indeed, <8% of men who engaged in high-risk practices used PEP. There may be several reasons why these men had not taken PEP. Previous Australian studies found that for many PEP users the experience of PEP was quite unpleasant and they would not recommend it to others.20 Some men may have not considered their practices risky enough or just failed to take an action. For men who reported having had UAIC, we suspect that some of these encounters may have been in the context of serosorting.21 We did not have data on the HIV status of casual partners to further investigate the issue. However, most men who reported having had unprotected anal intercourse with known serodiscordant partners had not taken PEP. We need to better understand this group of men and their risk reduction practices. It is also important to better understand how men assess their HIV risk, which risk events result in PEP use, and what prevents the majority of men from requesting PEP after high-risk events.22

Finally, by describing the profile of PEP users, our study highlights the groups of men who are already using ARVs as HIV prophylaxis. These groups will be in the focus of new biomedical HIV prevention in the future. An Australian HIV modeling study23 has found that targeting PrEP to men with high numbers of casual sex partners (≥10 in 6 months) and also men in serodiscordant regular relationships may have a significant impact on the HIV epidemic. Being exposed to HIV, these men may see PrEP as an attractive alternative to PEP (less reliant on recognizing a specific high-risk exposure) and may be willing to use it when it becomes accessible and affordable. At least 40% of gay men in the recent US study were already willing to use PrEP, even at 50% efficacy level.24 Several clinical trials are currently underway,25 to improve pharmacological characteristics of ARV agents, their toxicity profiles, drug delivery mechanisms, and acceptability to clients. There is already a strong movement to prepare for PrEP implementation,25–27 and the preliminary guidelines for its use have been issued in the United States.28,29

Although our study was conducted among Australian gay men, our findings and conclusion should be relevant to other gay communities in developed countries where current prevalence and predictors of PEP use have been reported to be similar.15

Some limitations of our behavioral surveillance data indicate areas where further research is needed. These include the lack of information about the serostatus of casual partners to estimate the actual prevalence of risk taking in the context of casual sex. Further, the design of the repeated cross-sectional surveys does not allow assessing sexual practices of PEP users after completing the treatment course. Although an Australian study found no evidence of behavior change after PEP use in mid-2000s,30 more research is needed to better understand the intersection of HIV biomedical prevention and sexual practices of gay men. Recent developments in biomedical prevention methods, specifically PrEP for HIV-negative gay men11 and earlier treatment initiation for the HIV-infected partners in serodiscordant relationships,31 will change the landscape of HIV prevention in the future. Research is needed to better understand the markets for and provision of these prevention methods, their possible effect on behavior, and on the use of PEP in the future.

In conclusion, this analysis has identified the profiles of current PEP users. It has also highlighted a substantial number of gay men who engage in risky sexual practices and are in need for effective HIV prevention strategies. These gay men may be receptive to effective biomedical prevention methods in the future. The results presented here suggest that a targeted approach is needed in incorporating biomedical methods in HIV prevention. That is, an approach focused on maintaining the culture of safe sex and supplementing it with evidence-based and correct use of biomedical prevention by gay men where it is suitable and needed.

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The authors would like to acknowledge the key community partners, the state-based AIDS Councils, and people living with HIV/AIDS organizations in each state for being instrumental in the conduct of the Gay Community Periodic Surveys. The authors would also like to thank all study participants for sharing their life experiences with the research team. The authors are also grateful for the financial support, which made this study possible.

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HIV; nonoccupational exposure; sexual practices; HIV prevention; postexposure prophylaxis; preexposure prophylaxis

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