Factors associated with reporting antibiotic use as STI prophylaxis among HIV PrEP users: findings from a cross-sectional online community survey, May–July 2019, UK

Abstract

ObjectivesThe use of antibiotics as pre-exposure or postexposure prophylaxis for sexually transmitted infection (STI) prevention (STI prophylaxis) is not currently recommended in the UK, but there is evidence that self-prescribing occurs among those at greatest risk. We present the prevalence and factors associated with STI prophylaxis among a community sample of HIV pre-exposure prophylaxis (PrEP) users.MethodsThe 2019 online PrEP User Survey ran between 17 May and 1 July. Eligible participants included UK residents reporting HIV PrEP use or having tried to obtain HIV PrEP since January 2017. STI prophylaxis use was defined as reporting buying antibiotics to prevent STIs, either privately or through the internet; this question was only asked to HIV PrEP users. Factors associated with STI prophylaxis use were assessed using univariable and multivariable logistic regression.ResultsOverall, 9% (167/1856) of HIV PrEP users reported STI prophylaxis use; 97% were gay or bisexual men, 84% reported white ethnicity, 55% resided in London and 69% were aged ≥35 years. Factors associated with STI prophylaxis included: reporting ≥5 compared with 1–4 condomless sex partners in the past 6 months (12% vs 5.6%, adjusted odds ratio (aOR)=1.80; 95% CI 1.22 to 2.64), reporting chemsex drug use compared with no sexualised drug use in the past 12 months (13% vs 6.0%, aOR=1.88; 95% CI 1.20 to 2.93) and reporting an STI diagnosis in the past 12 months (12% vs 6.6%, aOR=1.54; 95% CI 1.08 to 2.18). Variables not significant in multivariable analyses included: ethnicity, age, residence and HIV PrEP sourcing.ConclusionsApproximately 1 in 10 HIV PrEP users from this community sample reported self-prescribed STI prophylaxis. STI prophylaxis was associated with sexual behaviour known to facilitate STI transmission and with a history of recent STIs acquisition. Given the potential risk of antimicrobial resistance, sexual health clinicians should consider asking attendees, especially HIV PrEP users, about the use of antibiotics as STI prophylaxis, to inform appropriate counselling, testing and management.

Chemsex and diagnoses of syphilis, gonorrhoea and chlamydia among men who have sex with men in the UK: a multivariable prediction model using causal inference methodology

“…Public health responses to bacterial STIs require a multidisciplinary approach, transmission prevention strategies, screening and diagnostics, and intelligent allocation of antibiotics. 18 As such we need to identify key risk factors among MSM to signal which individuals would benefit from extra sexual health services and support. 19 The objective of this study is to examine the associations and potential effect of participation in chemsex on the acquisition of syphilis, gonorrhoea, and chlamydia to help address the relatively sparse amount of quantitative data available.…”

What is the role of sexual health services in the delivery of primary prevention of sexually transmitted infections? A narrative review

“…MSM on HIV-PrEP) are self-sourcing antibiotics to use as STI prophylaxis and healthcare providers should be aware of the issues. (78)(79)(80)(81)(82)(83) The future of primary prevention in SHS Whilst there are many strengths to the approach of delivering primary prevention in SHS, there are also several potential weaknesses and emerging challenges. SHS are limited in their physical and financial capacity to deliver care to those at risk of STIs.…”

BASHH updated position statement on doxycycline as prophylaxis for sexually transmitted infections

“…It advised ‘extreme caution in the use of doxycycline [as post-exposure prophylaxis (PEP)]…[and] that the use of doxycycline PEP should be restricted to the research setting’. However, increasingly evidence suggests that individuals at higher risk of acquiring bacterial STIs are already using antibiotics to prevent acquisition, accessed through several routes 2–5. Clinicians are therefore likely to be seeing patients who are self-sourcing antibiotics as STI prophylaxis.…”

“…Despite the lack of a large evidence base, up to 10% of HIV-PrEP-using MSM report taking antibiotic STI prophylaxis in surveys from the UK, Australia and the Netherlands2–6 — with comparable reported use among MSM living with HIV 10. Notably, interest and acceptability for STI prophylaxis among MSM is much higher, ranging from 53% to 84% in surveys 2 11.…”

“…Notably, interest and acceptability for STI prophylaxis among MSM is much higher, ranging from 53% to 84% in surveys 2 11. STI prophylaxis use has been found to be associated with higher risk behaviours, for example greater numbers of condomless sex partners and chemsex, and is also associated with STI diagnosis in the past 12 months 3 4. Although the most commonly used antibiotic for STI prophylaxis is doxycycline, emerging evidence suggests that up to 40% of MSM who report having ever used STI prophylaxis used an antibiotic other than doxycycline, such as azithromycin or amoxicillin — where there is no evidence of effectiveness in preventing bacterial STIs 10…”