title: Association of attention-deficit/hyperactivity disorder and atopic eczema modified by sleep disturbance in a large population-based sample.
abstract: BACKGROUND
  A cross-sectional study was performed in a population-based German sample (n=13 318 children and adolescents aged 3-17) to replicate the recently reported independent association of atopic eczema (AE) and attention-deficit/hyperactivity disorder (ADHD) and to further investigate the role of environmental and behavioural factors.
  
  
  METHODS
  The odds ratio (OR) was calculated with allergic comorbidity and various environmental factors considered as confounders and sleeping problems hypothesised to act as a potential effect modifier.
  
  
  RESULTS
  The lifetime prevalence of AE and ADHD was 14.7% (male 14.4%; female 14.9%) and 4.9% (male 7.8%; female 2.0%), respectively. There was an association between ADHD and AE (OR 1.54; 95% CI 1.24 to 1.93; p<0.001), which was independent of sociodemographic factors, parental smoking, breastfeeding, number of siblings, perinatal health problems, and atopic comorbidity. Further analyses of a subgroup of 6484 children age 3-11 confirmed the hypothesis that the association between AE and ADHD was modified by sleeping problems (interaction effect AE*sleep problems OR 2.02 95% CI 1.03 to 3.97; p=0.04). There was a strong association between AE and ADHD in children with SP (OR 2.67 95% CI 1.51 to 4.71; p=0.001; n=1112), but not in children without SP (OR 1.24 95% CI 0.83 to 1.84; p=0.30; n=5796).
  
  
  CONCLUSIONS
  ADHD and AE appear to be strongly and independently associated in children with sleeping problems, but not in children without sleeping problems. A substantial part of diagnoses met for ADHD might be engendered by the presence of AE and concomitant sleeping problems.
authors.affiliation: Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Clinic of Wuerzburg, Fuechsleinstr 15, 97080 Wuerzburg, Germany. romanos@kjp.uni-wuerzburg.de
authors.forename: Marcel
authors.initials: M
authors.lastname: Romanos
authors.forename: Manfred
authors.initials: M
authors.lastname: Gerlach
authors.forename: Andreas
authors.initials: A
authors.lastname: Warnke
authors.forename: Jochen
authors.initials: J
authors.lastname: Schmitt
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications* / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D015986:Confounding Factors, Epidemiologic; D003430:Cross-Sectional Studies; D003876:Dermatitis, Atopic / Q000150:complications* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D016017:Odds Ratio; D015995:Prevalence; D012893:Sleep Wake Disorders / Q000150:complications / Q000453:epidemiology