Risk reduction among HIV-seroconcordant and -discordant couples: the Zambia NOW2 intervention.

Heterosexual HIV transmission remains the leading cause of HIV incidence in adult men and women in sub-Saharan Africa. This study assessed whether an HIV risk-reduction intervention would be more likely to increase sexual barrier acceptability and decrease risk behavior when delivered to couples in gender concordant groups or in an individual format. This study also examined the mutual impact of couple members as a source of influence on acceptability, and assessed whether product acceptability, intimate partner violence (IPV), and/or partner communication predicted sexual barrier use. HIV seroconcordant and serodiscordant couples (n=216) were recruited in Lusaka, Zambia, and randomized to a four session gender-concordant intervention. Participants were assessed at baseline, 6, and 12 months. Willingness to use barriers (p=0.012), acceptability (p<0.001), and barrier use (p<0.001) increased over time in both conditions, and were influenced by gender preferences. IPV decreased (p=0.040) and positive communication increased (p<0.001) in both conditions. Individual and gender concordant group sessions achieved similar increases in sexual barrier use following the intervention. Results highlight the influence of partners as well as product acceptability as predictors of sexual barrier use among couples in sub-Saharan Africa. Future prevention studies should consider both product acceptability and partner influence to achieve optimal sexual risk behavior outcomes.