Among the estimated 1.2 million persons living with human immunodeficiency virus (HIV) infection in the United States in 2011, 14% were living with undiagnosed infection. The majority of persons who received a diagnosis of HIV infection in 2011 (62%) were men who have sex with men (MSM) (Centers for Disease Control and Prevention, 2015). Whereas Latinos overall continue to bear a disproportionate burden, representing 23% of new infections in the United States in 2013 in spite of comprising only 16% of the population, 81% new infections among Latinos were specifically among MSM (Centers for Disease Control and Prevention, 2013). For Latino men infected with HIV, the most common modes of transmission are male-to-male sexual contact and injection drug use (Tung, 2012). Recent alarming data was released by researchers at the Centers for Disease Control concluding that if current HIV diagnoses rates persist, about 1 in 2 black MSM and 1 in 4 Latino MSM in the United States will be diagnosed with HIV during their lifetime (Centers for Disease Control and Prevention, 2016).

Research has indicated that relationship status is not a protective factor against HIV (Starks, Gamarel, & Johnson, 2014; Sullivan, Salazar, Buchbinder, & Sanchez, 2009). For example, a study with 91 serodiscordant couples found that 30% of the couples engaged in risk taking and/or strategic positioning unprotected anal sex (Starks et al., 2014). Rates of new HIV infections among gay male couples may be in part due to their low levels of condom use, greater likelihood of having anal sex, and greater frequency of unprotected anal intercourse (UAI), thereby increasing their cumulative risk for HIV infection over time (Sullivan et al., 2009). Studies have also attributed the source of many new HIV and other sexually transmitted infections (STI) to primary partners (Kippax et al., 2003). In addition, behavioral studies consistently find that men are more likely to engage in condomless anal intercourse (CAI) with primary partners than with outside partners, especially in HIV concordant relationships (Frost, Stirratt, & Ouellette, 2008; Jin et al., 2009). Due to these trends, the context of relationship status is important for understanding and addressing HIV risk among Latino MSM.

Previous research has also explored relationship dynamics, including attachment, agreements, and intimacy within relationships, with CAI. For example, Hoff and colleagues (2012) found that a majority of male couples in their sample had agreements allowing sex outside the relationship and that a significant percentage of individuals have CAI outside of their relationship. They also found that men in concordant HIV positive and HIV discordant relationships were more likely to engage in CAI outside of their primary relationship than individuals in concordant HIV negative relationships. Among discordant couples, HIV positive individuals were substantially more likely to report engaging in CAI outside of their relationship than their HIV negative partners. In addition, couples who felt more connected to each other were more likely to have CAI within their relationship regardless of HIV status (Hoff, Chakravarty, Beougher, Neilands, & Darbes, 2012). Further research has found that although MSM are more likely to know the HIV status of primary partners than the status of casual partners, the majority of HIV transmissions among MSM are from primary partners due to greater overall frequencies of anal sex acts and decreased condom use within these relationships (Sullivan et al., 2009). HIV sexual risk behaviors are further impacted by attachment and sexual satisfaction within male partnerships, as well as the perceived seriousness of such partnerships (Ciesla, Roberts, & Hewitt, 2004; Udi Davidovich, de Wit, & Stroebe, 2006; Mustanski, Newcomb, & Clerkin, 2011). Starks and colleagues determined that securely attached, partnered MSM reported comparatively high levels of sexual communication within their relationships. Avoidantly attached men, on the other hand, reported engaging in CAI with more casual partners than those with other attachment styles (Starks & Parsons, 2014). Working specifically with serodiscorant male couples, Gamarel and colleagues found that the adoption of a “we” orientation was associated with increased engagement in protected anal intercourse among HIV+ men, whereas sexual satisfaction was associated with this outcome among their HIV- partners (Gamarel et al., 2014).

Interdependence theory (Rusbult & Van Lange, 2003) has been applied to HIV risk behaviors among male couples. According to this perspective, that men in relationships with other men make decisions regarding their sexual behavior with primary and outside partners based on a number of relationship factors, such as intimacy, autonomy, equality, commitment, satisfaction, and communication (U. Davidovich, de Wit, & Stroebe, 2000; De Wit, Stroebe, De Vroome, Sandfort, & Van Griensven, 2000). For some men, CAI is perceived as a way of showing love and intimacy to one another (Udi Davidovich, de Wit, & Stroebe, 2004; Heather, Alison, & Karen, 2002). This, in combination with the aforementioned associations between safer sex practices (i.e. engagement in protected and unprotected anal intercourse) and partner attachment, sexual satisfaction, and relationship seriousness, may help to account for the frequency with which HIV transmission occurs within (initially discordant) primary relationships. In addition, the investment model has been applied to examine interpersonal relationships (Le & Agnew, 2003; Rusbult, 1980). The model is comprised of four constructs: relationship satisfaction, quality of alternatives, investment size, and commitment level (Arriaga & Agnew, 2001). A meta-analysis of the Investment Model of commitment was conducted. Across 52 studies, including 60 independent samples and 11,582 participants, satisfaction with, alternatives to, and investments in a relationship each correlated significantly with commitment to that relationship. Support for the model was obtained in predicting commitment in both relational domains (e.g., commitment to a romantic partnership) and nonrelational domains (e.g., commitment to one's job), but was significantly stronger in relational domains (Le & Agnew, 2003).

While the interdependence theory and the investment model have been tested with couples, they have not been applied to Latino male couples, in particular, being inclusive of other social, cultural and structural factors that could potentially impact relationship dynamics. In addition, previous studies focus on the dyad and fail to recognize that individuals within couples may also engage with additional serious and casual sexual partners. Such oversights inhibit researchers' capacity to comprehensively address elements of satisfaction, investment and potential sexual risk behaviors.

While being in a relationship has been associated with HIV sexual risk behavior, there are conflicting data regarding the role relationships play in the substance use that may lead to sexual risk taking. One study found that alcohol consumption contributed to increased CAI with outside partners, but not with primary partners, although this could be due to the already high rates of CAI within primary relationships (Vanable et al., 2004). Furthermore, an exploratory study of alcohol's role in the sexual scripts of Black and Latino youth found that some individuals associated alcohol use with casual sex, but not with romantic sex (Mutchler, McDavitt, & Gordon, 2014). In a meta-review that was inclusive of (but not limited to) MSM, Claxton and colleagues determined that alcohol use was significantly associated with casual sexual relationships and experiences overall, although this relationship was considerably stronger for younger adults than for older adults (Claxton, DeLuca, & van Dulmen, 2015).

Parsons and colleagues found that alcohol plays a strong role in the sexual scripts of HIV positive MSM (Parsons et al., 2004). Specifically, in a sample of predominantly African American and Latino MSM, they found that many participants drank alcohol in order to lower their inhibitions before sex. This might lead to greater alcohol use among partnered MSM, due to their greater frequency of sexual encounters; however, strong bonds within relationships might also make alcohol use seem less necessary, as men may feel fewer inhibitions with their primary partners. In a later study, Parsons and colleagues (2013) found that it may be relationship agreements, not simply the presence or absence of relationships, that influences risk behaviors (Parsons, Starks, DuBois, Grov, & Golub, 2013). Specifically, they found that individuals in open and semi-monogamous relationships were more likely to use drugs than those in monogamous relationships.

Finally, it is important to remember that alcohol is only one of many substances that may facilitate sexual risk taking. Cocaine, marijuana, and party drugs such as ecstasy have also been associated with CAI, substance use in connection with sexual expectancies, and relationship agreements more broadly among MSM (Celentano et al., 2006; Colfax et al., 2004).

Limited research has examined the association between relationship status and sexual and substance use risk behaviors among a diverse sample of Latino MSM. Our study builds on previous qualitative and quantitative research (Beougher, Gomez, & Hoff, 2011; J. De Santis, 2012; J. P. De Santis, Vasquez, Deleon, & Gonzalez-Guarda, 2012) by examining the impact of relationship status on sexual and substance use risk behaviors among Latino MSM. There is an urgent need for research to advance our understanding of HIV risk behaviors among Latino men in same-sex relationships. Our study addresses a further gap in the literature in that the majority of participants are predominantly Spanish-speaking. Predominantly Spanish-speaking populations often have extra barriers to HIV testing and care, including language barriers; stigma (e.g., concerns with concealing their sexual behavior); less knowledge about HIV risks; documentation status; a lack of culturally and linguistically appropriate HIV testing and linkage care services; and financial concerns with regard to the cost of testing. In spite of these considerable barriers, predominantly and exclusively Spanish-speaking men have rarely been addressed in the literature on male couples.

Understanding how relationship status impacts risk behaviors could help to determine the extent to which providers should develop couple-specific interventions for Latino MSM, while also providing guidance for the development of such interventions. That is, with findings specific to Latino MSM, future studies can narrow their focus to create and implement more efficient interventions. Drawing on previous literature, we predicted that Latino MSM in primary relationships with other men would report engaging in more frequent CAI, whether within or outside of primary partnerships, than those who were not in such relationships. We further expected that this association would persist when controlling for a range of other factors, including alcohol and other substance use. Given our interest in developing interventions to address sexual risk behavior, we then conducted focus groups with Latino male couples and providers who serve them to further understand relationship dynamics and sexual behavior as well as identify strategies for translating these into effective, affirming, and culturally appropriate interventions.

This study was one of the first mixed-methods investigations to examine relationship dynamics, as well as the association between relationship status and sexual risk behavior, among Latino MSM. In bivariate analyses, participants in same-sex relationships reported more condomless anal intercourse than those who were not in such relationships, in addition to more high-risk alcohol consumption, more use of crack and powder cocaine, and more use of club and party drugs such as ecstasy. In multivariate analysis, participants in same-sex relationships were approximately five times as likely as those not in such relationships to report engaging in CAI. This is consistent with previous research (Hoff et al., 2012) indicating that individuals are more likely to engage in CAI within relationships. While we did not collect data regarding whether incidents of CAI occurred within or outside of primary relationships, we determined that half of participants in relationships reported multiple partners. Moreover, the highest frequencies of sexual partners (120) and incidents of CAI (168) in this study were both reported by participants in primary same-sex relationships.

Focus group participants indicated that interventions that focus on relationship dynamics, and are mindful and supportive of a range of agreements regarding (non)monogamy and fidelity, are sorely needed. Participants' observations about the changing dynamics of relationships are consistent with previous research (Hoff et al., 2012). Both providers and Latino MSM expressed concerns regarding HIV transmission within relationships. Many couples are not monogamous, and are inconsistent with condom use within and outside of primary relationships. These trends, along with a lack of information regarding prevention strategies, contribute to sexual risk behavior among Latino MSM. Some individuals might use condoms more consistently if they had the skills to negotiate more effectively with primary and casual partners. Those who are uninterested or otherwise unlikely to use condoms consistently could protect themselves by using biomedical strategies such as PrEP and HIV self-testing kits. However, many individuals lack knowledge of and access to such tools. Many Latino MSM and couples may feel discouraged or disempowered by discrimination and other barriers to care.

At the same time, many of our participants demonstrated resilience in the face of such obstacles, and a desire to affect social change. They did not merely perceive social and health services as avenues toward improving personal and couple wellbeing, but as resources for building knowledge and communal ties. Our participants expressed interest in promoting public education, and in changing popular perceptions of Latino MSM. Many acknowledged stereotypes of ill health and poor decision making, and portrayals of Latino MSM grounded only in suffering and marginalization, and demonstrated a commitment to challenging them. Researchers and providers might work to support and build on such resilience. Those who work with Latino MSM might empower clients/participants to promote communal wellbeing, perhaps by supplementing individual and couple-based interventions with opportunities to take part in public education and other forms of community activism.

Taken together, these findings speak to the potential value of couple-based interventions for Latino MSM. Quantitative data indicate that Latino men in same-sex relationships are more likely than their peers to engage in CAI; consequently, providers must be prepared to screen for relationship status and to provide services specifically for couples. For those couples who are disinterested in condom use but interested in HIV prevention, which was a notable theme in focus group discussions, couple-based interventions will provide an opportunity to educate about biomedical strategies such as PrEP, and to ensure that such strategies are only made available to individuals and couples with sufficient knowledge to use them properly. Given focus group participants' suggestion that the increasingly open nature of Latino MSM partnerships has intensified the burdens of communication within relationships, including negotiations regarding fidelity and safer sex practices, providers can offer ongoing support for these matters as well. Phone and internet-based services, as well as devoted time to discuss relationship concerns within in-person interventions, could go a long way to addressing couples' needs. Finally, as indicated by our focus group participants, couple-based services may offer an opportunity for providers to highlight and utilize the resilience of Latino MSM in relationships. Providers may empower couples to negotiate boundaries and prevention strategies, and to counter the feelings of invisibility and social marginalization that contribute to risk behavior.

There are some limitations to the present study. First, the quantitative component was limited to a cross sectional sample, and the qualitative component also had a relatively small sample size. Second, the present study did not track couple's relationships with substance use, specifically in regards to whether use within relationships was linked to one or both partners. In addition, we did not measure whether or not individuals who reported high-risk alcohol consumption and other substance use were in open or closed relationships, information that is important for creating interventions. Additionally, we omitted some potentially relevant variables, such as socioeconomic status markers such as income and employment status, from our survey due to the scope of the adaptation study. Future research should also explore the impact of relationship status and dynamics on the consumption of alcohol and other substances prior to sexual encounters. Such work might explore the impact of cultural taboos for some Latinos surrounding anal sex and different cultural attributes (e.g., machismo) that can conflict with same-sex relationship dynamics, potentially leading to sexual risk behavior and high-risk alcohol consumption. For example, researchers have found that behaviorally bisexual Latino men navigate their same-sex relationships in secrecy (Garcia, Muñoz-Laboy, Parker, & Wilson, 2014). Machismo also dictates that men must avoid “feminine behaviors,” be perceived as powerful and prove their manhood by taking risks (Ayala et al., In press; Rhodes et al., 2009; Royster, Richmond, Eng, & Margolis, 2006). Having multiple partners and not using condoms may imply masculinity for some. Sexual and gender minority Latinos/as may feel further compelled to take risks to “overcome” perceived external assumptions and internal negative feelings about their orientation and masculinity (Rhodes, Yee, & Hergenrather, 2006; Sandfort, Melendez, & Diaz, 2007).

Further limitations concern our operationalization of condomless anal intercourse. While we based these measures on previous research, including some focused specifically on MSM of color (Wu et al., 2011; Reece et al., 2010), they only captured a portion of relevant behaviors and risk factors: total number of anal sex partners, total number of anal sex encounters, and total number of CAI encounters over the previous three months; we then dichotomized participants as reporting “no CAI” or “any CAI” in this time period. Practically speaking, we also relied on participants' ability to accurately recall three months' worth of sexual behaviors, as well as their comfort in sharing this information. We did not distinguish between insertive and receptive behaviors. We did not capture information regarding whether participants engaged in CAI with primary partners, casual partners, or both; nor did we capture information regarding associations between participants and partners' serostatus and decisions regarding safer sex practices. Finally, we did not inquire as to whether incidents of CAI might be still be protected (e.g., through the use of PrEP). Future research should assess sexual behaviors in greater detail, incorporating nuances regarding the associations among relationship status, relationship agreement, sexual role (i.e., insertive, receptive, or both), and considerations in regards to serostatus. It may also be worth collecting data for behaviors over shorter time periods, such as 30 days, to mitigate concerns about accurate recall.

The present study has increased understanding of the dynamics of Latino MSM relationships with regard to CAI and alcohol and other substances. The study's finding that Latino MSM in relationships are more likely to engage in CAI, and that the effects of alcohol and other substance use on CAI may be mediated by relationship status, can help inform interventions and programs. Furthermore, the resilience of Latino male couples and the steps this group has already taken to increase their knowledge of and access to care should be leveraged in future interventions with this population. In addition, providers must adapt and be responsive to the needs of the Latino MSM and work to develop culturally appropriate and affirming interventions. It is clear that there is a need for culturally grounded, couple-based HIV/AIDS prevention interventions as a means of addressing sexual and substance use risk behavior. These concerns are pressing considering that Latino MSM continue to be disproportionately affected by HIV.