The generational effect on age disparate partnerships and the risk for human immunodeficiency virus and sexually transmitted infections acquisition

Abstract

In South Africa, a large proportion of young women are in age disparate relationships, which is believed to be a risk factor for human immunodeficiency virus (HIV). The aim of this study was to determine the generational effect of age disparity on HIV and sexually transmitted infection (STI) incidence. Socio-demographic and behavioural data were collected from women, aged 16 and older, who were followed for up to 24 months. Women who reported having a steady sexual partner older than themselves were categorised into: (1) non-age disparate partnerships (age difference between partners was 0-4 years); (2) intra-generational age disparate partnerships (5-9 year age gap between sexual partners); and (3) inter-generational age disparate partnerships (age gap of 10 years or more between sexual partners). Of the 1355 women included in the analysis, 759, 429 and 167 were in non-age disparate, intra-generational age disparate and inter-generational age disparate partnerships, respectively. Strong predictors of inter-generational age disparate partnerships include age, marital status and concurrency of sexual partners. No significant relationship between age disparity and risk of HIV acquisition was found. The highest crude STI incidence was observed among those in intra-generational age disparate relationships followed by those in non-age disparate relationships (31.86 [26.41-38.44] and 25.60 [21.92-29.91] per 100 person-years, respectively). Reduction of multiple partnerships remains key to HIV prevention; however, in light of partner concurrency being more prevalent than individual concurrency partnerships, female-initiated HIV prevention options remain critical.

Age differences between sexual partners, behavioural and demographic correlates, and HIV infection on Likoma Island, Malawi

“…Harling et al did not find evidence that among women 15–30 years old, age differences were associated with increased hazard of HIV acquisition18. Likewise, Street et al also could not reject the null hypothesis that women who were in age-disparate relationships would have the same HIV incidence as those in similar-age relationships14. However, our results from the semiparametric analysis indicate that this may not be the full story.…”

“…In particular, women may have some increased risk of being HIV positive if their male partners are older than them by approximately 2–12 years, but then may be slightly protected if their partners are more than 12 years older. The analysis conducted by Street et al produced similar, albeit non-significant, trends: the HIV incidence among women in steady sexual partnerships was 5.78 per 100 person-years with partners who were 0–4 years older, 7.50 with partners 5–9 years older, and 3.67 with partners 10 or more years older14. While in our study the associations between mean/max age differences and HIV status in women were not statistically significant, we do believe there is in fact a bimodal association that is meaningful and relevant for HIV transmission dynamics.…”

“…It is convention and makes it easy to compare results across studies and settings (some prominent examples include61314), 2. It also allows us to directly compare the men and women in our study population, and 3.…”

“…Additionally, higher sexual risk behaviours have been associated with age-asymmetric relationships. Specifically, men in these relationships use condoms less frequently1011, and have more concurrent partnerships121314 than in relationships where men and women are of similar ages. Young women in age-asymmetric relationships also display behaviours and have characteristics which may put them at increased risk for HIV infection: increased reports of STI treatment or symptoms101115, more lifetime partners10, earlier sexual debut10, and higher sex frequency10.…”

Effect of Schooling on Age-Disparate Relationships and Number of Sexual Partners Among Young Women in Rural South Africa Enrolled in HPTN 068

“…13,28 Conversely, age disparity did not appear to be associated with incident HIV infection in other studies from South Africa and Uganda. 29–32 While age disparity and number of partners appear to be factors in the relationship between time spent in school and risk of HIV infection, how these behaviors further increase risk of HIV warrants further investigation.…”