title: Early tobacco smoking in adolescents with externalizing disorders: inferences for reward function.
abstract: BACKGROUND
  Tobacco smoking is the leading preventable cause of mortality in the United States, and 90% of regular smokers initiate smoking before age 18 years. Factors that confer risk for chronic smoking include psychiatric factors, such as externalizing disorders, and potentially related neurobiological substrates, such as reward function. The present study examined the relationship between the externalizing disorders and the temporal progression of smoking among adolescent smokers.
  
  
  METHODS
  Data were from 64 adolescents who requested smoking cessation treatment and included information on developmental smoking trajectory, number of cigarettes per day, and Fagerström Test for Nicotine Dependence score. This sample was assessed carefully for psychiatric disorders. Analyses examined the relationships between externalizing psychiatric disorders and smoking trajectory.
  
  
  RESULTS
  Adolescents with an externalizing disorder consumed more tobacco in the first 2 years of smoking than those without a disorder. There were no differences in speed of progression between groups, which may index a distinct functional pattern of reward systems that confers vulnerability for tobacco dependence.
  
  
  CONCLUSIONS
  These data are discussed in terms of potential predictors of early smoking behavior that can inform interventions for adolescents with externalizing behaviors and tobacco dependence. They also provide some hypotheses for how the development of chronic smoking can be influenced by specific patterns of reward responses.
authors.affiliation: Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA. aklinwm@mail.nih.gov
authors.forename: Will M
authors.initials: WM
authors.lastname: Aklin
authors.forename: Eric T
authors.initials: ET
authors.lastname: Moolchan
authors.forename: David A
authors.initials: DA
authors.lastname: Luckenbaugh
authors.forename: Monique
authors.initials: M
authors.lastname: Ernst
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D019958:Attention Deficit and Disruptive Behavior Disorders / Q000453:epidemiology*; D015897:Comorbidity; D005260:Female; D006801:Humans; D007389:Internal-External Control; D008297:Male; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology*; D014029:Tobacco Use Disorder / Q000453:epidemiology*; D055815:Young Adult