title: Family income trajectory during childhood is associated with adolescent cigarette smoking and alcohol use.
abstract: BACKGROUND
  Although childhood socioeconomic disadvantage has been linked with adolescent tobacco and alcohol use in cross-sectional research, less is known about the influence of changes in socioeconomic status during childhood. Upward socioeconomic mobility may attenuate the negative influence of earlier socioeconomic disadvantage on health, while downward mobility may counter the health benefits of earlier socioeconomic advantage. This study evaluated the influence of common trajectories of family income during childhood on smoking and alcohol use during adolescence.
  
  
  METHODS
  Data utilized were part of the 15-year longitudinal Study of Early Child Care and Youth Development. A 5-class trajectory model (two stable, one downward, and two upward income trajectories) was developed previously with this sample (N=1356). Logistic regression analyses were conducted to determine whether children of the more disadvantaged income trajectories were more likely to engage in tobacco and alcohol use at age 15 relative to those of the most advantaged trajectory.
  
  
  RESULTS
  Family income trajectory was significantly associated with ever-smoking (p=.02) and past-year alcohol use at age 15years (p=.008). Children from the less advantaged trajectories were more likely to have ever-smoked than children of the most advantaged trajectory (all p's<.05). Children of the downwardly mobile trajectory were more likely to have used alcohol within the past year than children of the most advantaged trajectories as well as the most disadvantaged trajectory (all p's<.05).
  
  
  CONCLUSIONS
  Findings indicate that childhood socioeconomic disadvantage influences adolescent smoking, while downward socioeconomic mobility influences adolescent alcohol use.
authors.affiliation: The University of Texas Health Science Center, School of Public Health, 6011 Harry Hines Boulevard, Dallas, TX 75390-9128, USA. Electronic address: Insiya.B.Poonawalla@uth.tmc.edu.
authors.forename: Insiya B
authors.initials: IB
authors.lastname: Poonawalla
authors.affiliation: The University of Texas Health Science Center, School of Public Health, 6011 Harry Hines Boulevard, Dallas, TX 75390-9128, USA; The University of Texas Southwestern Medical Center, Harold C. Simmons Cancer Center, Population Science and Cancer Control Program, Dallas, TX, USA. Electronic address: Darla.Kendzor@UTSouthwestern.edu.
authors.forename: Darla E
authors.initials: DE
authors.lastname: Kendzor
authors.affiliation: The University of Texas at Dallas, School of Behavioral and Brain Sciences, 800W. Campbell Road, Richardson, TX 75080-3021, USA. Electronic address: MOwen@UTDallas.edu.
authors.forename: Margaret Tresch
authors.initials: MT
authors.lastname: Owen
authors.affiliation: The University of Texas Health Science Center, School of Public Health, 6011 Harry Hines Boulevard, Dallas, TX 75390-9128, USA. Electronic address: Margaret.Caughy@UTSouthwestern.edu.
authors.forename: Margaret O
authors.initials: MO
authors.lastname: Caughy
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D000428:Alcohol Drinking / Q000453:epidemiology*; D005190:Family; D005260:Female; D006801:Humans; D007182:Income / Q000706:statistics & numerical data*; D008297:Male; D012907:Smoking / Q000453:epidemiology*; D012923:Social Class; D012937:Social Mobility / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology
keywords: Adolescence; Alcohol; Poverty; Smoking; Socioeconomic disadvantage; Socioeconomic status