Risk of HIV infection among adolescent girls and young women in age-disparate relationships in sub-Saharan Africa.

Objective: To determine the association between age-disparate relationships and risk of HIV infection among adolescent girls and young women (AGYW) aged 15-24 years.

Design: Systematic review and meta-analysis of published studies until January 5, 2020 in sub Saharan Africa (SSA).

Methods: We searched several electronic databases, grey literature, and hand searched reference list of included studies to identify eligible studies for data abstraction. We assessed the quality of included studies using Newcastle-Ottawa Scale for nonrandomized studies. The DerSimonian-Laird random effects model was used to pool the overall results using risk ratios (RR), presented in a forest plot with 95% confidence interval (CI) and predictive interval. Heterogeneity was assessed with Cochrane's Q-test and quantified with I values. Publication bias was checked with funnel plots and Egger's test.

Results: We included 24 studies with an overall sample size of 33 390. Data show that age-disparate relationships were significantly associated with unprotected sexual intercourse (pooled RR, 1.57; 95% CI, 1.34-1.83; 95% predictive interval, 1.22-2.02), and higher risk for HIV infection (pooled RR, 1.39; 95 CI, 1.21-1.60; 95% predictive interval, 0.80-2.42). Studies included in pooling risk of unprotected sexual intercourse were largely homogeneous (I-value= 0.0, P = 0.79) whereas those for HIV infection were heterogeneous (I- value = 89.0%, P < 0.01). We found no publication bias and no study influenced the meta-analytic results.

Conclusion: Age-disparate relationships among AGYW are associated with increased risk of unprotected sexual intercourse and HIV infection in SSA. HIV prevention interventions should target this sub-population.