AIDS (London, England) 2017 04 19() doi 10.1097/QAD.0000000000001506
Age-disparate sexual relationships with older men may drive high rates of HIV acquisition in young women in sub-Saharan Africa but evidence is limited. We investigate the association between age-disparate relationships and HIV incidence in Manicaland, Zimbabwe.
A general-population open-cohort study (six surveys) (1998-2013).
3746 young women aged 15-24 years participated in consecutive surveys and were HIV-negative at the beginning of inter-survey periods. Last sexual partner age difference and age-disparate relationships (inter-generational [≥10 years age difference] and intra-generational [5-9 years] versus age-homogeneous [0-4 years]) were tested for associations with HIV incidence in Cox regressions. A proximate determinants framework was used to explore factors possibly explaining variations in the contribution of age-disparate relationships to HIV incidence between populations and over time.
126 HIV infections occurred over 8777 person-years (1.43 per 100 person-years; 95% confidence interval=1.17-1.68). 65% of women reported partner age differences of ≥5 years. Increasing partner age differences were associated with higher HIV incidence (adjusted hazard ratio [aHR]=1.05 [1.01-1.09]). Inter-generational relationships tended to increase HIV incidence (aHR=1.78 [0.96-3.29]) but not intra-generational relationships (aHR=0.91 [0.47-1.76]). Secondary education was associated with reductions in inter-generational relationships (adjusted odds ratio [aOR]=0.49 [0.36-0.68]). Inter-generational relationships were associated with partners having concurrent relationships (aOR=2.59 [1.81-3.70]) which tended to increase HIV incidence (aHR=1.74 [0.96-3.17]). Associations between age-disparity and HIV incidence did not change over time.
Sexual relationships with older men expose young women to increased risk of HIV acquisition in Manicaland, which did not change over time, even with introduction of antiretroviral therapy.This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. http://creativecommons.org/licenses/by/4.0.