title: Correlates of adolescent sleep time and variability in sleep time: the role of individual and health related characteristics.
abstract: OBJECTIVE
  Adolescents are predisposed to short sleep duration and irregular sleep patterns due to certain host characteristics (e.g., age, pubertal status, gender, ethnicity, socioeconomic class, and neighborhood distress) and health-related variables (e.g., ADHD, asthma, birth weight, and BMI). The aim of the current study was to investigate the relationship between such variables and actigraphic measures of sleep duration and variability.
  
  
  METHODS
  Cross-sectional study of 247 adolescents (48.5% female, 54.3% ethnic minority, mean age of 13.7years) involved in a larger community-based cohort study.
  
  
  RESULTS
  Significant univariate predictors of sleep duration included gender, minority ethnicity, neighborhood distress, parent income, and BMI. In multivariate models, gender, minority status, and BMI were significantly associated with sleep duration (all p<.05), with girls, non-minority adolescents, and those of a lower BMI obtaining more sleep. Univariate models demonstrated that age, minority ethnicity, neighborhood distress, parent education, parent income, pubertal status, and BMI were significantly related to variability in total sleep time. In the multivariate model, age, minority status, and BMI were significantly related to variability in total sleep time (all p<.05), with younger adolescents, non-minority adolescents, and those of a lower BMI obtaining more regular sleep.
  
  
  CONCLUSIONS
  These data show differences in sleep patterns in population sub-groups of adolescents which may be important in understanding pediatric health risk profiles. Sub-groups that may particularly benefit from interventions aimed at improving sleep patterns include boys, overweight, and minority adolescents.
authors.affiliation: The Sleep Center, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA. melisamoore@gmail.com
authors.forename: Melisa
authors.initials: M
authors.lastname: Moore
authors.forename: H Lester
authors.initials: HL
authors.lastname: Kirchner
authors.forename: Dennis
authors.initials: D
authors.lastname: Drotar
authors.forename: Nathan
authors.initials: N
authors.lastname: Johnson
authors.forename: Carol
authors.initials: C
authors.lastname: Rosen
authors.forename: Susan
authors.initials: S
authors.lastname: Redline
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000502:physiology*; D001249:Asthma / Q000208:ethnology; D001289:Attention Deficit Disorder with Hyperactivity / Q000208:ethnology; D015992:Body Mass Index; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008913:Minority Groups / Q000706:statistics & numerical data*; D012111:Residence Characteristics; D012307:Risk Factors; D012890:Sleep / Q000502:physiology*; D012893:Sleep Wake Disorders / Q000208:ethnology* / Q000503:physiopathology*; D012959:Socioeconomic Factors; D013997:Time Factors