Abstract
BackgroundThe extent to which individuals are similar to their sexual partners influences STI-transmission probabilities, yet there is a dearth of empirical data, especially those representative of the population.MethodsAnalyses of data reported by 10 759 sexually active people aged 16–74 y interviewed for a British national probability survey undertaken in 2010–12. Computer-assisted self-interviews asked about partner numbers and characteristics of participants’ three most recent partnerships (MRPs). Opposite-sex MRPs were weighted to represent all such partnerships in the past year (N = 16 451). Estimates of disassortative age mixing (≥±5-y difference), ethnic mixing (partner of a different ethnic group) and geographical mixing (partner from a different region/country when they first met) were calculated, stratified by gender, age group and partnership status (casual/steady). Multivariable regression examined how these disassortative mixing measures were associated with STI-risk measures: condom use at first sex together at the partnership-level and, at the participant-level, STI-risk perception and reporting STI diagnoses.ResultsDisassortative age mixing occurred in around one-third of opposite-sex partnerships, with men ≥5 y older in most cases, although this proportion varied by participant’s gender and age group. Ethnic mixing occurred less frequently (11.3% of men’s and 8.6% of women’s partnerships) as did geographical mixing (14.1 and 16.3%, respectively). Disassortative mixing was more common among casual vs steady partnerships. Condom use at first sex was less likely in women’s partnerships that were age-disassortative [adjusted odds ratio (AOR): 0.79, 95% confidence interval (CI): 0.69–0.95], whereas men reporting disassortative ethnic mixing were more likely to perceive themselves at STI risk (AOR: 1.76, 95% CI: 1.23–2.52) and report STI diagnoses (AOR: 2.37, 95% CI: 1.22–4.59).ConclusionsDisassortative mixing, although uncommon among opposite-sex partnerships in Britain, is independently associated with STI risk, warranting consideration in STI-prevention efforts.
Highlights
The extent to which individuals are similar to their sexual partners influences Sexually transmitted infection (STI)-transmission probabilities, yet there is a dearth of empirical data, especially those representative of the population
In most opposite-sex partnerships in Britain, individuals were similar to their partners as disassortative age mixing (!65-y age difference) occurred in approximately one-third of partnerships, whereas disassortative ethnic and geographical mixing were less common
STI-prevention efforts may benefit from taking account of sexual mixing patterns as well as individual-level risk factors
Summary
The extent to which individuals are similar to their sexual partners influences STI-transmission probabilities, yet there is a dearth of empirical data, especially those representative of the population. Where mixing is largely disassortative (i.e. individuals tending to have sexual partners with different characteristics and behaviours to themselves8), more generalized approaches may be more appropriate, e.g. population screening Between these two extremes lies mixing at random, i.e. people having sex with partners at random such that there is no pattern in how their own characteristics and behaviours relate to those of their partners
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
