title: The role of social networks and geography on risky injection behaviors of young persons who inject drugs.
abstract: BACKGROUND
  Little is known about young persons who inject drugs (PWID), who are increasingly from suburban communities and predominantly non-Hispanic white.
  
  
  METHODS
  We conducted a cross-sectional personal network (egocentric) and geographic study of young PWID and their drug-using, sexual, and support network members in 2012-13 in metropolitan Chicago, Illinois, U.S.
  
  
  RESULTS
  We enrolled 164 young (median age=26), mostly male (65%), non-Hispanic white PWID (71%), with a self-reported HCV prevalence of 13%. Many (59%) reported multiple residences (i.e., were transient) in the past year, 45% of whom reported living in both urban and suburban places (i.e., were cross-over transients). In multivariable analyses that adjusted for participant and network member characteristics, (1) large injection networks were more common among homeless participants; and (2) syringe sharing was (a) highest among cross-over transients compared to suburban (OR=4.19 95% CI 1.69-10.35) and urban only residents (OR=2.91 95% CI 1.06-8.03), (b) higher among HCV-unknown compared HCV-negative participants (OR=4.62 95% CI 1.69-10.35), (c) more likely with network members who were cross-over transients compared to urban (OR=4.94, 95% CI 2.17-11.23) and (d) less likely with network members with HCV-unknown compared to HCV-negative status (OR=0.4 95% CI 0.19-0.84).
  
  
  CONCLUSIONS
  We identified homelessness as a significant risk factor for large networks and cross-over transience as a significant risk factor for syringe sharing. Further research is needed to understand the role of geographic factors promoting higher risk among these crossover transient PWID.
authors.affiliation: Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, 1603 West Taylor Street, M/C 923, Chicago, IL, 60612, USA. Electronic address: bboodram@uic.edu.
authors.forename: Basmattee
authors.initials: B
authors.lastname: Boodram
authors.affiliation: Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, 1603 West Taylor Street, M/C 923, Chicago, IL, 60612, USA. Electronic address: mmamiti@uic.edu.
authors.forename: Mary-Ellen
authors.initials: ME
authors.lastname: Mackesy-Amiti
authors.affiliation: Department of Epidemiology & Department of Health, Behavior and Society, Bloomberg School of Public Health, Johns Hopkins University, 624 N, Broadway, Hampton House 737, Baltimore, MD 21205, USA. Electronic address: carl_latkin@jhu.edu.
authors.forename: Carl
authors.initials: C
authors.lastname: Latkin
mesh_terms: D000328:Adult; D002641:Chicago / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006526:Hepatitis C / Q000453:epidemiology / Q000523:psychology / Q000821:virology; D006703:Ill-Housed Persons / Q000523:psychology* / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D016485:Needle Sharing / Q000523:psychology / Q000706:statistics & numerical data; D015995:Prevalence; D012309:Risk-Taking; D012944:Social Support; D015819:Substance Abuse, Intravenous / Q000453:epidemiology* / Q000523:psychology*; D013383:Suburban Population; D014481:United States; D014505:Urban Population; D055815:Young Adult
keywords: Homeless; Injection networks; Persons who inject drugs; Syringe sharing; Transient; Young