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Children with atopic dermatitis (AD) and attention-deficit/hyperactivity disorder (ADHD) or a learning disability are at increased risk of cognitive impairment and should be prioritised for assessment, research suggests.
Previous studies had suggested AD was associated with cognitive impairment in children, US researchers wrote in the journal JAMA Dermatology, but it was unknown whether certain subpopulations of children with AD were at greater risk.
To answer this question, lead study author Dr Joy Wan, assistant professor of dermatology at the Johns Hopkins University School of Medicine, and colleagues designed a cross-sectional study using data from the 2021 US National Health Interview Survey (NHIS).
Drawing on a weighted sample of 69,732,807 children (13.2% with AD), researchers found when compared to those without the condition, children with the condition were more likely to experience learning difficulties (10.8% vs 5.9%) and memory difficulties (11.1% vs 5.8%).
In multivariable logistic regression models adjusted for sociodemographic factors, asthma, food and seasonal allergies, AD was associated with increased odds for learning difficulties (adjusted odds ratio: 1.77) and memory difficulties (adjusted odds ratio 1.69).
However, further analysis showed the association was primarily limited to children with neurodevelopmental comorbidities, such as ADHD or learning disabilities, pointing to them being the subgroups of children with AD at highest risk of cognitive impairment.
‘The findings of this study suggest that evaluation for cognitive impairment in children with AD should be prioritised among those with comorbid neurodevelopmental disorders,’ Dr Wan and colleagues wrote.
While the mechanism underlying the interaction between AD and neurodevelopmental disorders was unknown, it was possible that AD-related sleep disturbances might be more likely to negatively impact cognitive functions in children with ADHD or learning disability, the authors continued.
‘Our results also suggest that memory and learning difficulties related to AD may vary by developmental condition,’ Dr Wan and colleagues added.
In children with ADHD, for example, AD was associated with nearly three-times greater risk of memory difficulties but was not associated with learning difficulties.
However, in children with learning disabilities, AD was linked with twice the odds of memory difficulties but half the odds of learning difficulties.
It was possible that children with AD and concomitant learning disabilities were more likely to receive appropriate interventions, perhaps due to greater healthcare use or caregiver awareness, leading to relatively lower odds of reported learning difficulties.
‘Another possibility is that AD affects different areas of cognition to varying degrees, with perhaps a greater impact on memory than on learning,’ Dr Wan and colleagues said.
The study included children aged 17 years and younger without intellectual disability or autism, the researchers said, noting that strengths of the research included its population-based nature and the data adjustment for confounders.
Limitations included the cross-sectional study design and reliance on caregiver-reported symptoms.
‘Finally, we were unable to examine factors, such as AD severity, age at AD diagnosis, and sleep, which were not collected in the NHIS data,’ the researchers wrote.
