title: Influence of asthma status on sleep variability in overweight/obese youth.
abstract: OBJECTIVE
  Pediatric asthma and overweight/obesity (OV/OB) frequently co-occur and youth with both conditions exhibit poor sleep/bedtime habits. This study assessed differences in week-to-weekend bedtime/wake time variability among OV/OB youth with/without comorbid asthma, and tested whether variability predicted weekday sleep.
  
  
  METHODS
  OV/OB youth (n = 142; 28% comorbid asthma; 7-12 years) wore an Accelerometer for 5 days (2 weekend days), providing estimates of week-to-weekend bedtime/wake-time variability, weekday Total Sleep Time (TST), weekday time in bed (TIB), and weekday wake after sleep onset (WASO).
  
  
  RESULTS
  There were no demographic differences between groups beyond lower family income for the OV/OB+asthma group. The OV/OB+asthma group exhibited later weekday (mean OV/OB+asthma = 10:39 pm, mean OV/OB only = 10:30pm) and weekend (mean OV/OB+asthma = 11:41 pm, mean OV/OB only = 11:17pm) bedtimes, earlier weekday waketimes (mean OV/OB+asthma = 6:40 am, mean OV/OB only = 6:51 am), and similar weekend waketimes (mean OV/OB+asthma = 7:54 pm, mean OV/OB only = 7:52 pm. Univariate MANOVA follow-ups indicated a main effect of asthma group for week-to-weekend bedtime and waketime variability, with the OV/OB+asthma group evidencing approximately 30 minutes greater bedtime (OV/OB+asthma mean = 90 minutes) and waketime (OV/OB+asthma mean = 108 minutes) variability. Within the OV/OB+asthma group, greater waketime variability predicted fewer minutes of weekday TIB and WASO. Within the OV/OB only group, wake time variability predicted fewer minutes of weekday TIB.
  
  
  CONCLUSIONS
  Findings suggest that asthma status confers risk for more week-to-weekend variability among currently OV/OB youth, and that greater variability shortens the weekday sleep period. Further research on reasons for greater week-to-weekend sleep variability in asthma is needed.
authors.affiliation: a Department of Clinical and Health Psychology , University of Florida , Gainesville , FL , USA.
authors.forename: Kendra N
authors.initials: KN
authors.lastname: Krietsch
authors.affiliation: a Department of Clinical and Health Psychology , University of Florida , Gainesville , FL , USA.
authors.forename: Casey
authors.initials: C
authors.lastname: Lawless
authors.affiliation: a Department of Clinical and Health Psychology , University of Florida , Gainesville , FL , USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Fedele
authors.affiliation: b Department of Health Psychology , University of Missouri , Columbia , MO , USA.
authors.forename: Christina S
authors.initials: CS
authors.lastname: McCrae
authors.affiliation: a Department of Clinical and Health Psychology , University of Florida , Gainesville , FL , USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Janicke
mesh_terms: D001249:Asthma / Q000453:epidemiology*; D002648:Child; D005260:Female; D006184:Habits; D006801:Humans; D008297:Male; D050177:Overweight / Q000453:epidemiology*; D063766:Pediatric Obesity / Q000453:epidemiology*; D012890:Sleep / Q000502:physiology; D012893:Sleep Wake Disorders / Q000453:epidemiology*; D012959:Socioeconomic Factors
keywords: Sleep medicine; child; pediatric; pulmonology