Multiplex Relationships and HIV: Implications for Network-Based Interventions.

The number of network members and the roles they play can influence risk behaviors and consequently intervention strategies to reduce HIV transmission. We recruited 652 people who use drugs (PWUD) from socially disadvantaged neighborhoods in New York City (07/2006-06/2009). Interviewer-administered surveys ascertained demographic, behavioral, and network data. We used logistic regression, stratified by exchange sex, to assess the relationship between HIV status and the number of network members with different roles, treated as independent and multiplex (i.e., drug + sex). Those with more multiplex risk ties were significantly more likely to be HIV positive, but only among those not reporting exchange sex (AOR = 3.2). Among those reporting exchange sex, men reporting recent male sex partners were more likely to report HIV positive status (AOR = 12.6). These data suggest that sex and drug relationships among PWUD are interrelated. Interventions that target multiplex rather than single-role relationships may be more effective in influencing behavior change.