Factors associated with prior engagement in high-risk sexual behaviours among adolescents (10–19 years) in a pastoralist post-conflict community, Karamoja sub-region, North eastern Uganda

BACKGROUND: Adolescent sexual risky behaviours continue to be significant drivers of the HIV epidemic globally. The objective of this study was to determine factors associated with prior engagement in high-risk sexual behaviours among adolescents (10–19 years) in Karamoja sub-region, a pastoralist and post-conflict community in North-eastern Uganda. METHODS: Between August and September 2016, we conducted a cross-sectional study among 1439 adolescents receiving primary healthcare services at nine public health facilities located in five of the seven districts that make up Karamoja sub-region. High-risk sexual behaviour was defined as engaging in sex with two or more (2+) sexual partners in the 6 months preceding the survey or exchanging sex for money or gifts with no or inconsistent use of condoms over the same period of time. Factors associated with prior engagement in high-risk sexual behaviours were analysed using a modified Poison regression model with log-link and Poisson-family via a generalized linear model. RESULTS: Eighty-two percent (81.8%, n = 1177) of the respondents had ever tested for HIV while 62 % (61.5%, n = 885) had ever had sex. Of those that had ever had sex, 11.4% (n = 101) reported prior engagement in high-risk sexual behaviours. Prior engagement in high-risk sexual behaviours was lower among men than women (adjusted prevalence ratio (adj. PR) = 0.46; 95% Confidence Interval (95% CI): 0.33, 0.62) and those whose sex debut was above 14 years (adj.PR = 0.63; 95% CI: 0.57, 0.69). However, prior engagement in high-risk sexual behaviours was significantly higher in adolescents who were not aware of their recent sexual partner’s HIV status (adj.PR = 2.43; 95% CI: 1.68, 3.52) and those who used illicit drugs (adj.PR = 2.76; 95% CI: 1.88, 4.05). CONCLUSION: Prior engagement in high-risk sexual behaviours was significantly associated with having sex with partners of unknown HIV sero-status and use of illicit drugs. These findings suggest a need for targeted interventions to improve mutual HIV status disclosure between sexual partners while minimizing their use of illicit drugs/substances. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12889-019-7352-6) contains supplementary material, which is available to authorized users.