Background: We performed a cross-sectional study in a population-based German sample (n=13,318 children and adolescents aged 3-17) to replicate the recently reported independent association of AE and ADHD and to further investigate the role of environmental and behavioural factors.
Methods: We calculated odds ratios [OR] 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 (odds ratio 1.54; 95%-confidence interval [95%CI] 1.24-1.93; p<.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 6,484 children age 3 to 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 1.03-3.97; p=.04). There was a strong association between AE and ADHD in children with SP (OR 2.67 95%CI 1.51-4.71; p=.001; n=1,112), but not in children without SP (OR 1.24 95%CI 0.83-1.84; p=.30; n=5,796).
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 presence of AE and concomitant sleeping problems.