title: Demographic and behavioral contextual risk groups among men who have sex with men participating in a phase 3 HIV vaccine efficacy trial: implications for HIV prevention and behavioral/biomedical intervention trials.
abstract: Recent outbreaks of syphilis and gonorrhea coupled with reported increases in HIV-risk behavior among men who have sex with men (MSM) have raised concerns about a potential resurgence of HIV among MSM. These concerns have led some to suggest the need for a paradigm shift in how HIV-prevention programs are designed and implemented. In this analysis, baseline demographic, sexual partnership, and substance use information was used to identify contextual-risk groups among 5,095 HIV-seronegative MSM enrolled in a 36-month phase 3 HIV vaccine efficacy trial across 61 sites primarily in North America. Eight demographic and behavioral contextual risk groups were identified, with annualized HIV seroincidence ranging from 1.8% to 6.3% across groups. Men in primary HIV-serodiscordant relationships had the lowest HIV seroincidence (1.8%), while an older group of men with many sex partners had the highest (6.3%). Visit-schedule compliance and study retention were lowest among younger non-White men and highest among older popper users, with annualized HIV seroincidence of 2.9% and 3.5%, respectively. Differences in HIV incidence, study compliance, and retention observed among contextual-risk groups suggest that responsiveness to heterogeneity within risk group (eg, MSM) could benefit screening, enrollment, and retention of HIV-prevention programs and intervention trials, reducing the time and cost related to their design, implementation, and conclusion.
authors.affiliation: Vaccine Section, Epidemiology Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, 16000 Clifton Road, Atlanta, GA 30333, USA. bnb1@cdc.gov
authors.forename: Bradford N
authors.initials: BN
authors.lastname: Bartholow
authors.forename: Vamshidar
authors.initials: V
authors.lastname: Goli
authors.forename: Marta
authors.initials: M
authors.lastname: Ackers
authors.forename: Eleanor
authors.initials: E
authors.lastname: McLellan
authors.forename: Marc
authors.initials: M
authors.lastname: Gurwith
authors.forename: Marcus
authors.initials: M
authors.lastname: Durham
authors.forename: Alan E
authors.initials: AE
authors.lastname: Greenberg
mesh_terms: D016915:AIDS Vaccines / Q000276:immunology*; D000328:Adult; D000375:Aging; D017326:Clinical Trials, Phase III as Topic; D016000:Cluster Analysis; D003710:Demography; D015658:HIV Infections / Q000276:immunology / Q000517:prevention & control* / Q000635:transmission; D007722:Health Knowledge, Attitudes, Practice; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012725:Sexual Behavior / Q000706:statistics & numerical data*
chemical_list: D016915:AIDS Vaccines