title: Dose-response associations between number and frequency of substance use and high-risk sexual behaviors among HIV-negative substance-using men who have sex with men (SUMSM) in San Francisco.
abstract: We evaluated the relationship between frequency and number of substances used and HIV risk [ie, serodiscordant unprotected anal intercourse (SDUAI)] among 3173 HIV-negative substance-using MSM. Compared with nonusers, the adjusted odds ratio (AOR) for SDUAI among episodic and at least weekly users, respectively, was 3.31 [95% confidence interval (CI), 2.55 to 4.28] and 5.46 (95% CI, 3.80 to 7.84) for methamphetamine, 1.86 (95% CI, 1.51 to 2.29) and 3.13 (95% CI, 2.12 to 4.63) for cocaine, and 2.08 (95% CI, 1.68 to 2.56) and 2.54 (95% CI, 1.85 to 3.48) for poppers. Heavy alcohol drinkers reported more SDUAI than moderate drinkers [AOR, 1.90 (95% CI, 1.43 to 2.51)]. Compared with nonusers, AORs for using 1, 2, and ≥3 substances were 16.81 (95% CI, 12.25 to 23.08), 27.31 (95% CI, 18.93 to 39.39), and 46.38 (95% CI, 30.65 to 70.19), respectively. High-risk sexual behaviors were strongly associated with frequency and number of substances used.
authors.affiliation: San Francisco Department of Public Health, San Francisco, CA 94102, USA. glenn-milo.santos@sfdph.org
authors.forename: Glenn-Milo
authors.initials: GM
authors.lastname: Santos
authors.forename: Phillip O
authors.initials: PO
authors.lastname: Coffin
authors.forename: Moupali
authors.initials: M
authors.lastname: Das
authors.forename: Tim
authors.initials: T
authors.lastname: Matheson
authors.forename: Erin
authors.initials: E
authors.lastname: DeMicco
authors.forename: Jerris L
authors.initials: JL
authors.lastname: Raiford
authors.forename: Eric
authors.initials: E
authors.lastname: Vittinghoff
authors.forename: James W
authors.initials: JW
authors.lastname: Dilley
authors.forename: Grant
authors.initials: G
authors.lastname: Colfax
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Herbst
mesh_terms: D000328:Adult; D000428:Alcohol Drinking; D003042:Cocaine; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D018023:HIV Seronegativity; D018451:Homosexuality, Male; D006801:Humans; D013287:Illicit Drugs; D008297:Male; D008385:Marijuana Smoking; D008694:Methamphetamine; D009566:Nitrates; D016017:Odds Ratio; D000439:Pentanols; D012309:Risk-Taking; D012495:San Francisco; D019966:Substance-Related Disorders / Q000150:complications*; D047568:Unsafe Sex / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D013287:Illicit Drugs; D009566:Nitrates; D000439:Pentanols; D008694:Methamphetamine; D003042:Cocaine; C036285:amyl nitrate