Recreational drug use and risks of HIV and sexually transmitted infections among Chinese men who have sex with men: Mediation through multiple sexual partnerships

HIV risks in China have been shifting from injection drug use and contaminated plasma collection to unprotected sexual contacts in the last decade [1],[2], and the rapid increase of male-to-male HIV transmission is of particular concern [3]-[6]. From a tiny proportion of new HIV/AIDS cases in 2005, transmission among men who have sex with men (MSM) was reported for 70,000 (23%) of the new HIV cases in the first nine months of 2013 [4]-[7].

Unprotected anal intercourse is the primary risk factor for HIV infection among MSM [8],[9]. MSM who are recreational drug users may be more susceptible to infection of HIV and sexually transmitted infections (STIs) compared to their non-drug using peers [10]. A recent review showed a wide range (0.1% -44%; median 2.4%)of MSM reporting ever using recreational drugs, higher than that in the general population [1],[11]-[14].

Recreational drug use (RDU) may increase risk for HIV/STI acquisition by disinhibiting behavior, impairing judgment such that safer sex practices are bypassed, and/or increasing sexual desire [15]. Disinhibition and opting out of safer sex has been termed “cognitive escape” which undermines HIV prevention [15]-[17]. Most studies assess the relationship between RDU and sexual risk behavior [18], or examine HIV risk among drug users [10]. Some studies have shown sexual risk behaviors are associated with both RDU and HIV infection, suggesting that a more complex model should be employed to examine these associations. As expected, a mediating role of sexual risk behaviors in the pathway between RDU and acquisition of HIV and STIs has been observed [15]. We propose a conceptual model to examine the mediating role of sexual risk behaviors between RDU and risks of HIV, syphilis, and human simplex virus type 2 (HSV-2). We sought to examine further the associations of RDU, sexual risk, and HIV/STIs among MSM in urban China.

HIV was more common in MSM with multiple partners and using recreational drugs. A non-significant trend was seen for RDU and syphilis, but no association was noted for HSV-2. The mediation models suggested a strong role of RDU and multiple partnerships for predicting HIV risk, with less influence from unprotected sex. Prevention programs for Chinese MSM are not heavily dependent on condom promotion; RDU and partner numbers are foci for further community engagement and education. We cannot say whether RDU is a contributor to higher risk behaviors, or is a part of a matrix of linked activities, as when high risk sex is pre-planned along with RDU. While we found only 0.42% of participants reported having ever injected drugs in the past six months, use of non-injected recreational drugs was common among Chinese MSM [1] with 28.5% of participants reporting their use in the past six months. We believe that RDU is a neglected topic in current MSM risk reduction interventions in China [22]-[25].

The link between RDU and HIV risk has been described among MSM populations worldwide [19],[26]-[28], and RDU has also been linked to increased risk behaviors in MSM [29],[30]. However, there is sparse empiric evidence about the potential role of risky sex in the path between RDU and HIV infection in China. Our mediation analysis suggested that multiple partnerships, but not unprotected sex, acted as a mediator in the relationship between RDU and HIV infection. Since condom use clearly diminishes HIV risk, we speculate that our limited self-reported measure of condom use in the current study did not capture the effect of unprotected sex; we only asked participants if they used condom in their last sex act, and this did not measure long-term effects of unprotected sex in the acquisition of HIV and other STIs. Alternatively, condom use may not be a sensitive indicator of HIV risk among MSM [5].

The strengths of this study included a large sample size from multiple large Chinese cities, and using definitive laboratory tests with confirmations to measure HIV, syphilis and HSV-2 infections. Our mediation analysis helps advance the causal models. Limitations of the study include the limits of a cross-sectional study design that do not permit causal inferences between RDU and HIV, syphilis, and HSV-2 infections. A second limitation is that homosexuality in China is illegal and stigmatized, such that our data regarding sexual behaviors may be subject to socially desirable bias. Third, there are likely other unmeasured mediators on the pathways between drug use and HIV infection. Last, though the six large study cities represent different geographical locations and HIV prevalence in general population, the survey employed a convenience sample of study cities, and participants from these cities may not represent all Chinese MSM, as those who live in small cities and towns may have different drug use and sexual behaviors.

This study extends existing literature by examining the mediating role of sexual risk behaviors on the path between drug use and infections of HIV, syphilis and HSV-2. To address the issue of increased risk sex among drug using MSM, HIV intervention programs may use innovative approaches, like “behavioral-structural” approach which combines behavioral, psychological and biomedical components to curtail these ongoing epidemics [31],[32]. First, HIV interventions among MSM should not only screen drug use, but also reduce sexual risk behaviors. Second, although the Chinese government has launched multiple large harm reduction programs, e.g., methadone maintenance treatment [33], these programs target persons who inject drugs, and programs for MSM are limited [1]. MSM face double barriers for access to harm reduction programs, including illicit nature of drug use and stigma attached to homosexuality. Chinese harm reduction programs should address RDU and make drug treatment services more widely accessible to MSM population. Third, due to the prevailing homophobia in China, MSM are usually hidden and invisible from health professionals and policy makers. Peer-led risk reduction interventions led by gay-friendly community-based organizations may be more effective among Chinese MSM than formal government health sector programs [34]. Fourth, interventions employing longer follow-up time to help promote behavior self-management skills are more likely to be effective for MSM risk reduction than more superficial engagements [35].MSM in China represent the fastest growing group of persons at risk and RDU is a neglected topic vis-à-vis risk in this key population.