Background: Social support reciprocity (the extent to which people exchange mutual support) is associated with long-term health.

Method: We examined whether overall social support and reciprocity of support between people living with HIV and their treatment partners (informal caregivers selected from patients' social networks to support adherence) are associated with HIV viral suppression. A total of 130 patients living with HIV and their treatment partners were recruited from a clinic in Gaborone, Botswana, from May 2016 to April 2017. Participants completed surveys assessing sociodemographic and social network characteristics. Patients and treatment partners rated their emotional closeness to each other (not at all close = 0, somewhat close = 1, very close = 2).

Results: Multivariable logistic regressions indicated a significantly higher likelihood of viral suppression among patients who reported greater average emotional closeness to social network members. The likelihood of viral suppression was lower in asymmetric relationships in which patients felt closer to treatment partners than treatment partners felt to them (compared to when treatment partners felt closer to patients); this negative effect was strongest in dyads with female treatment partners

and male patients. Follow-up analyses additionally indicated that asymmetric relationships in which treatment partners felt closer to patients were as protective as symmetric relationships, in which patients and treatment partners felt equally close.

Conclusion: Perceptions around reciprocity may matter as much as overall relationship closeness in patients' health outcomes. Interventions to improve the support of informal caregivers could help to improve relationship quality and health outcomes among people with HIV.

Keywords: Botswana; Caregivers; HIV; Patient adherence/compliance; Social support.