title: Long-term effects of minimum legal drinking age laws on marijuana and other illicit drug use in adulthood.
abstract: BACKGROUND
  Exposure to permissive minimum legal drinking age (MLDA) laws (ability to purchase alcohol <21 years) during adolescence can have long-term effects, including heavy alcohol use or alcohol use disorders as adults. We examined whether exposure to permissive MLDA laws during adolescence has long-term effects on illicit drug use and disorders in adulthood.
  
  
  METHODS
  Participants from the 2004-2012 National Survey of Drug Use and Health (NSDUH) were linked with historical state MLDA laws. Participants born in 1949-1972 (age 31-63 years at observation, n = 110,300) were analyzed because they came of legal age for alcohol purchase when changes occurred in state MLDA laws. Logistic regression was used to model drug use measures as a function of exposure to permissive MLDA during adolescence, adjusting for state and birth-year fixed effects, demographics, and salient state characteristics.
  
  
  RESULTS
  Rates of past month use, past year use, and abuse/dependence of marijuana were 4.7%, 7.8%, and 1.2%, respectively. Rates of past month use, past year use, and abuse/dependence of illicit drugs other than marijuana were 2.9%, 6.2%, and 0.7%, respectively. Among the full sample, exposure to permissive MLDA laws was not significantly associated with drug use or abuse/dependence in adulthood. Men exposed to permissive MLDA laws were at 20% increased odds of past year illicit drug use (aOR 1.20, 95% CI 1.09-1.32).
  
  
  CONCLUSIONS
  Restricting alcohol access during adolescence did not increase long-term drug use. Allowing the purchase of alcohol among those less than 21 years of age could increase the risk of drug use later in life.
authors.affiliation: Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA. Electronic address: kraussm@psychiatry.wustl.edu.
authors.forename: Melissa J
authors.initials: MJ
authors.lastname: Krauss
authors.affiliation: Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Cavazos-Rehg
authors.affiliation: Department of Psychology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
authors.forename: Arpana
authors.initials: A
authors.lastname: Agrawal
authors.affiliation: Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Bierut
authors.affiliation: Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Grucza
mesh_terms: D000328:Adult; D000367:Age Factors; D000428:Alcohol Drinking / Q000331:legislation & jurisprudence*; D005260:Female; D006306:Health Surveys; D006801:Humans; D013287:Illicit Drugs / Q000331:legislation & jurisprudence*; D016015:Logistic Models; D008297:Male; D002189:Marijuana Abuse / Q000453:epidemiology*; D008385:Marijuana Smoking / Q000453:epidemiology*; D008875:Middle Aged; D019966:Substance-Related Disorders / Q000453:epidemiology*; D013997:Time Factors; D014481:United States / Q000453:epidemiology
chemical_list: D013287:Illicit Drugs
keywords: Alcohol policy; Illicit drugs; Marijuana; Minimum legal drinking age