(P224) Sexualised drug use and sexually transmitted infections among adolescent men who have sex with men

Background: Drug use, particularly sexualised drug use, has been associated with an increased risk of acquiring sexually transmitted infections (STI). Sexualised drugs generally refer to the drugs used to facilitate sex, including methamphetamine, mephedrone and gamma-hydroxybutyrate (GHB). Most research on sexualised drug use and STIs was conducted among adult men who have sex with men (MSM). There have been very limited studies on adolescent MSM, particularly young people who may be more susceptible to drug use. This study aimed to examine drug use and its association with STI diagnosis among adolescent MSM in Melbourne.

Methods: The HYPER2 study was a cohort of MSM aged 16-20 years recruited in Melbourne, Australia, aimed at examining the prevalence of human papillomavirus (HPV) after gender-neutral, school-based HPV vaccination was implemented. As part of the study, data on drug use was collected and men received HIV/STI screening. We calculated the proportion of men who used any drugs, sexualised drugs, and polydrug (more than one drug). Univariable and multivariable logistic regression was performed to examine the association between sexualised drugs and STI.

Results: Of the 179 men included in this analysis, 59% (n=105) had used any drug in the past 6 months, with the most common drug being marijuana (44%, n=78), followed by poppers (38%, n=68). 11% (n=20) used sexualised drugs(i.e. methamphetamine, mephedrone and GHB). Polydrug use was reported by 36% (n=65) of men with marijuana and poppers being the most common combination (18%, n=12) (Figure 1). The prevalence of any STI (gonorrhoea, chlamydia and infectious syphilis) was 16% (n=28), and there was no new HIV diagnosis. Multivariable analyses showed that using sexualised drugs had higher odds of acquiring any STI (aOR=8.83; 95%CI: 1.03-75.90), after adjusting for education level, condomless sex and the number of partners; however, there was no significant association between any drug use and STI (aOR=1.62; 95%CI: 0.52-5.08).

Conclusion: Sexualised drug use is common among adolescent MSM and is associated with an increased risk of STI. This suggests the need for interventions integrating both sexual health and substance use for adolescent MSM.