Age-disparate relationships and HIV incidence in adolescent girls and young women: evidence from a general-population cohort in Zimbabwe
- Resource Type
- Authors
- Schaefer, R; Gregson, S; Eaton, JW; Mugurungi, O; Rhead, R; Takaruza, A; Maswera, R; Nyamukapa, C
- Source
- Subject
- MARRIAGE
young women
Science & Technology
ACQUISITION
Immunology
HIV prevention
age-disparate relationships
11 Medical And Health Sciences
06 Biological Sciences
HIV incidence
SOUTH-AFRICA
TRENDS
17 Psychology And Cognitive Sciences
adolescent girls
Infectious Diseases
PARTNERSHIPS
Virology
INFECTION
RISK-FACTORS
COHORT
HEALTH
older men
Life Sciences & Biomedicine
- Language
Objective: 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. Design: A general-population open-cohort study (six surveys) (1998-2013). Methods: 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. Results: 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. Conclusions: 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.