What Do We Know?
7.5 Gaps and Limitations in HIV Couple-Based Prevention and Future Directions
7.5.1 Defi nition of a Couple
Existing couple-based models vary in their defi nition of a “couple.” Most rely on the index participant to identify his or her partner. Several existing models use more stringent criteria, such as the length of the relationship and the nature of living arrangements. For example, Project Connect used the following criteria. To be con-sidered a member of a couple, a woman had to (1) be between 18 and 55 years old;
(2) have a regular, male sexual partner whom she identifi ed as a boyfriend, spouse, or lover; (3) be in a long-term relationship, operationalized as involvement with this partner for at least the past 6 months, with the intention to stay with him for at least 1 year; (4) have had at least one episode of unprotected vaginal or anal sex with this partner within the past 30 days; (5) have not reported any severe physical or sexual
abuse by this partner within the past 6 months, as defi ned by selected questions from the Revised Confl ict Tactics Scale (Straus et al. 1996 ) ; and (6) be a patient at one of the hospital’s outpatient clinics. Harvey et al. ( 2004 ) , the Eban NIMH multisite study, and Project Renaissance (Gilbert et al. 2010 ) all use similar criteria. These criteria may limit the ability to generalize from study fi ndings to all couples, and to men who have sex with men (MSM).
7.5.2 Methodological Challenges
Couple-based HIV interventions are still in the early stages of development. Most existing couple-based prevention studies remain limited by one or more method-ological drawbacks, including relatively small sample sizes, lack of a randomized control design, and/or lack of biologically confi rmed STIs as an outcome (Burton et al. 2008 ) . Thus far, of the existing couple-based models only three studies have used biological outcomes (Coates et al. 2000 ; NIMH Multisite HIV/STD Prevention Trial for African American Couples Group 2008 ; Gilbert et al. 2010 ). None of the currently reported studies with couples have had suffi cient power to examine any new incidence of HIV as an outcome.
7.5.3 Partner Concurrency as an Outcome
Most of the empirically tested, couple-based HIV prevention approaches reviewed have not looked at whether these approaches reduce partner concurrency. This is an important outcome to consider because partner concurrency increases the HIV risk among couples as well as within their social network (Halperin and Epstein 2004 ) . It is also not clear whether these existing approaches have any effect on HIV risks with other partners outside of the dyad.
So far, studies of couple-based HIV prevention have been unable to determine the optimal intervention modality. Is the intervention more effective when sessions are provided individually to each couple, when sessions are provided to several couples in a group, or when they are provided to a small, single-gender group of individuals who are in coupled relationships? The HIV couple-based prevention approaches reviewed in this chapter have used one or a combination of these modal-ities. Research on HIV couple-based interventions should tackle these questions.
Accurate answers would improve the science of couple-based HIV prevention.
7.5.4 Focusing on Couple Dynamics
Although the existing couple-based studies reviewed in this chapter are designed to address the couple dynamics, the majority of these studies did not focus on the
couple’s relationship and contexts – such as how gender roles, gender expectations, couple communications, and sexual dysfunction within the dyad contributes to HIV risks (Burton et al. 2008 ) . In the context of emerging biomedical interventions for HIV prevention, such as microbicides and Pre-exposure prophylaxis (PrEP) couple-based research will be necessary to inform the most effective modes of delivery and implementation in real-world settings.
Microbicides, which are currently and likely to remain only partially effective in reducing transmission risk, need to be used vaginally or rectally prior to (and during) sexual intercourse. How they can be used effectively in the context of sexual inter-course between two people is still in need of research. While it is possible for one person, such as the woman, to use the product, early research has shown that partner acceptability and participation is necessary for successful and consistent use of such products. Thus, utilization of these produces will not be entirely under the control of one person, but will need to involve partner cooperation and participation (Abdool Karim et al. 2011 ; Grant et al. 2010 ) .
PrEP thus far has also been shown to be only partially effective in reducing HIV transmission. Research is needed to identify comparative effectiveness of PrEP in the HIV-negative partner in the dyad as compared to ART in the HIV-positive part-ner. Also, how will the couple integrate partially effective tools such as microbi-cides and PrEP into their sex lives and how might the use of biomedical interventions affect the use of condoms and other barrier methods among couples (Abdool Karim et al. 2011 , Grant et al. 2010 ) .
7.5.5 Couple-Based Theories
Most couple-based HIV prevention approaches are guided by individual-based the-ory, such as social learning and cognitive behavioral theories (Ajzen and Fishbein 1980 ; Bandura 1977a, b ; Bandura and Adams 1977 ; Beck 1975 ; Rosenstock et al.
1988 ) . These theories assume that couples are motivated to take protective actions, and often overlook many relationship and dyadic factors. Moreover, it is still unclear which populations are most responsive to the interventions (moderators), and what mechanisms and mediators lead to behavioral change. To advance the science of HIV intervention with couples, the most useful theories are those that focus on fi ne-grained relationship structures and contexts.
7.5.6 Couple Data Analytic Approaches
Although data from existing prevention and treatment studies were collected from the couples, most of the studies reviewed employed individual-data analytical approaches. The use of couple-based data would advance HIV prevention and
treatment science for this modality and answer questions on the effi cacy of the intervention used in the existing studies. More attention should be given to couple-data analytical techniques.
7.5.7 Male Couples
Unfortunately, thus far, no HIV prevention intervention targeting male couples has been tested, in spite of the fi nding that many MSM are infected by steady partners (Sullivan et al. 2009 ) . There are several HIV prevention interventions for MSM that have shown effi cacy in reducing transmission risk behaviors among HIV-positive and HIV-negative MSM, with mixed results as to whether risk reduction took place with steady as opposed to casual partners (Johnson et al. 2005 ) .
7.5.8 HIV Drug Risk Reduction with Couples
HIV prevention with IDU couples is also limited. Existing couplebased HIV effi -cacy trials have minimal content in their core components on HIV drug risk reduc-tion behaviors, such as the proper way to clean syringes, needles, and other drug equipment, and HIV risks associated with sharing syringes and other drug parapher-nalia with main sex partners (Burton et al. 2008 ) . Moreover, couple-based HIV pre-vention is not an approach commonly used in drug treatment and HIV services for IDUs. Bringing IDUs and their regular sexual partners together in an HIV preven-tion intervenpreven-tion can be an effective strategy to reduce both sexual and drug risk behaviors, and to lower HIV transmission.
7.5.9 Couple-Focused Adherence to HIV Care and Treatment
There is a need for more research on couple-based approaches to improving ence to HIV care and treatment. Since social support is an important factor in adher-ence to care, partners of patients with chronic illness can play an important and instrumental role in optimizing adherence, as described earlier. As with couple-based HIV prevention research, gaps remain in our knowledge of optimal interven-tion modalities for couple-focused interveninterven-tions to improve adherence. There are gaps in research on couples’ relationship dynamics and contexts, such as how gen-der roles, gengen-der expectations, and a couple’s communications contribute to HIV healthcare behaviors. Research is lacking on the specifi c forms of practical support that spouses and partners actually offer in support transactions. Research is needed on couples in which both members are HIV infected, and on how differences play out depending on the individual’s stage of illness, so that interventions can be tailored for a wide range of couples.