title: Findings from within-subjects comparisons of drug use and sexual risk behaviour in men who have sex with men in England.
abstract: Epidemiological evidence for the encounter-level association between sexualised drug use and unprotected anal intercourse in men who have sex with men is unclear and has not examined men who have sex with men in England. To estimate this association, we compared dyadic sexual encounters within respondents. We used encounter-level data from a longitudinal online survey of men who have sex with men living in England and multilevel models to test univariate and multivariate associations between any respondent or partner drug use, specific respondent drug use, additional situational characteristics and unprotected anal intercourse. Based on 6742 encounters from 2142 men who have sex with men, respondent drug use and respondent use of certain specific drugs were associated with increased unprotected anal intercourse odds. In univariate models, partner drug use was associated with increased unprotected anal intercourse odds, but in multivariate models, only non-specific knowledge of partner drug use was associated with the same. Encounters with non-regular-and-steady partners or that were not HIV-seroconcordant were associated with decreased unprotected anal intercourse odds. This is the first within-subjects comparison of drug use and unprotected anal intercourse conducted on a sample from England, and the largest of its kind. Findings are consistent with other studies, though associations between drug use and unprotected anal intercourse are shaped by social contexts that may change over time.
authors.affiliation: 1 Warwick Evidence, Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry, UK.
authors.forename: G J
authors.initials: GJ
authors.lastname: Melendez-Torres
authors.affiliation: 2 Sigma Research, London School of Hygiene and Tropical Medicine, University of London, London, UK.
authors.forename: Ford
authors.initials: F
authors.lastname: Hickson
authors.affiliation: 2 Sigma Research, London School of Hygiene and Tropical Medicine, University of London, London, UK.
authors.forename: David
authors.initials: D
authors.lastname: Reid
authors.affiliation: 2 Sigma Research, London School of Hygiene and Tropical Medicine, University of London, London, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Weatherburn
authors.affiliation: 3 Department of Social Science, UCL Institute of Education, University College London, London, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: Bonell
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004739:England / Q000453:epidemiology; D018451:Homosexuality, Male; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012306:Risk; D012309:Risk-Taking; D012747:Sexual Partners; D000072339:Sexual and Gender Minorities / Q000523:psychology / Q000706:statistics & numerical data*; D019966:Substance-Related Disorders / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D047568:Unsafe Sex / Q000523:psychology / Q000706:statistics & numerical data*; D055815:Young Adult
keywords: Epidemiology; high-risk behaviour; homosexual; sexual behaviour