title: Latent class analysis of non-opioid dependent illegal pharmaceutical opioid users in Ohio.
abstract: BACKGROUND
  Increases in non-medical use of pharmaceutical opioids in the U.S. have resulted in increases in opioid dependence and unintentional overdose deaths. We characterize heterogeneity in opioid use patterns among a community-based sample of 18-23 year-olds who use non-medical pharmaceutical opioids, yet are not opioid dependent.
  
  
  METHODS
  Respondent-driven sampling recruited 390 participants. Latent class analysis stratified by racial/ethnic group identified subgroups of non-medical opioid users based on: six-month frequency of use; number of opioid disorder criteria; oral vs. non-oral administration; number of types of opioids used; use of CNS depressants while under using opioids; and reason for opioid use. Multinomial logistic regression estimated the significance of covariates in predicting class membership.
  
  
  RESULTS
  Within whites and non-white groups, three classes emerged that were, generally, hierarchically ordered with respect to negative characteristics associated with non-medical opioid use. Within each group, the class with the least negative characteristics also had the highest proportion of individuals who use opioids only to self-medicate a health problem. Within each group's three classes, a larger proportion who had ≥ 2 opioid abuse and dependence disorder criteria always coincided with a larger proportion who use opioids ≥ 3 days per week, a larger proportion who used CNS depressants while under the influence of opioids, and a smaller proportion who used opioids only to self-medicate.
  
  
  CONCLUSIONS
  Differences in patterns of opioid use within each racial/ethnic group of young people who are not opioid dependent suggest the need for tailored interventions designed to reduce the risk of transition to opioid dependence.
authors.affiliation: Center for Interventions, Treatment, and Addiction Research, Department of Community Health, Boonshoft School of Medicine, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH 45435, United States. Electronic address: robert.carlson@wright.edu.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Carlson
authors.affiliation: Division of Morphological Sciences and Biostatistics, Lifespan Health Research Center, Department of Community Health, Boonshoft School of Medicine, Wright State University, 3171 Research Boulevard, Dayton, OH 45420, United States.
authors.forename: Ramzi W
authors.initials: RW
authors.lastname: Nahhas
authors.affiliation: Center for Interventions, Treatment, and Addiction Research, Department of Community Health, Boonshoft School of Medicine, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH 45435, United States.
authors.forename: Raminta
authors.initials: R
authors.lastname: Daniulaityte
authors.affiliation: Department of Epidemiology, Columbia University Mailman School of Public Health, New York, NY 10032, United States.
authors.forename: Silvia S
authors.initials: SS
authors.lastname: Martins
authors.affiliation: Center for Interventions, Treatment, and Addiction Research, Department of Community Health, Boonshoft School of Medicine, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH 45435, United States.
authors.forename: Linna
authors.initials: L
authors.lastname: Li
authors.affiliation: Center for Interventions, Treatment, and Addiction Research, Department of Community Health, Boonshoft School of Medicine, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH 45435, United States.
authors.forename: Russel
authors.initials: R
authors.lastname: Falck
mesh_terms: D000293:Adolescent; D000701:Analgesics, Opioid / Q000008:administration & dosage*; D003625:Data Collection / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D009820:Ohio / Q000453:epidemiology; D009293:Opioid-Related Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D063487:Prescription Drug Misuse / Q000639:trends; D015813:Substance Abuse Detection / Q000379:methods*; D055815:Young Adult
chemical_list: D000701:Analgesics, Opioid
keywords: Emerging adults; Latent class analysis; Non-medical pharmaceutical opioid use; Opioid dependence