Atopic Dermatitis and Academic Achievement-More to Learn

Atopic dermatitis, cognitive function and psychiatric comorbidities across early childhood and adolescence in a population-based UK birth cohort

BACKGROUND

Atopic dermatitis (AD) may affect cognitive function, but studies are limited and inconsistent. The effect of AD severity on cognition remains underexplored and few previous studies have examined clinically validated or repeated measures of cognition throughout childhood.

OBJECTIVES

To evaluate the relationship of AD activity and severity with validated measures of general cognition in a longitudinal birth cohort.

METHODS

We conducted cross-sectional analyses using data from the Avon Longitudinal Study of Parents and Children (ALSPAC), a UK cohort of 14 975 individuals followed prospectively since their birth in 1991-92. AD was assessed 11 times between the age of 6 and 166 months. Mothers were asked if their child had an 'itchy, dry skin rash in the joints and creases', and AD status was time-updated accordingly as 'never', 'maybe', 'inactive', 'active/mild' or 'active/moderate-severe'. General cognition [i.e. intelligence quotient (IQ)] was measured at 18, 49, 103 and 186 months of age using the Griffiths Mental Development Scales (GMDS), Wechsler Preschool and Primary Scale of Intelligence (WPPSI), Wechsler Intelligence Scale for Children (WISC) and Wechsler Abbreviated Scale of Intelligence (WASI), respectively. Multivariable linear regression was used to compare IQ with respect to nearest time-updated AD status. Secondary analyses were stratified by the presence or absence of psychiatric or learning disorders. An exploratory longitudinal analysis of IQ across all four outcome assessments was conducted using generalized estimating equations.

RESULTS

No significant associations between AD status and full-scale IQ scores on the GMDS, WPPSI, WISC and WASI were observed after adjustment for sociodemographic factors, atopic comorbidities and sleep characteristics. However, at 8 years of age, WISC Performance IQ was slightly, although statistically significantly, lower among children with active/moderate-severe AD [β coefficient -2.16, 95% confidence interval (CI) -4.12 to -0.19] and Verbal IQ was slightly, but statistically significantly, higher among those with inactive AD (β coefficient 1.31, 95% CI 0.28-2.34) compared with those without AD. Analyses stratified by psychiatric or learning disorders, and exploratory longitudinal analyses of cognition revealed similar findings.

CONCLUSIONS

We did not find any clinically meaningful associations between AD activity and severity and general cognitive function during early childhood and adolescence. Future studies should incorporate objective measures of AD severity and investigate outcomes beyond IQ.

Melatonin and Sleep Disturbances in Children With Atopic Dermatitis

Objective

To evaluate the correlation between melatonin levels and sleep quality, based on the Children’s Sleep Habit Questionnaire (CSHQ), among children with atopic dermatitis (AD).

Methods

This was an analytic study with a cross-sectional design involving two groups, AD children as the case group and participants without AD as the control group, conducted at the Pediatric Dermatology Clinic of Dr. Hasan Sadikin Hospital, Bandung, Indonesia. Melatonin levels and CSHQ score in the case group were compared to that in the control group. Correlation analysis was performed between melatonin levels and sleep quality based on CSHQ in the case group.

Results

Participants in this study consisted of 19 children with moderate AD, (no patient with mild and severe AD was recruited), and 19 participants without AD. The mean CSHQ score in the case group was significantly higher than the control group (47.84 vs 36.79; p<0.05). The mean melatonin level in the case group was significantly lower than the control group (320.18 pg/mL vs 383.86 pg/mL; p<0.05). Comparative analysis was conducted using independent t-test. There was a significant Pearson’s correlation index between SCORAD and CSHQ (p<0.05). However, there was no correlation between melatonin levels and CSHQ, as well as between melatonin levels and SCORAD (p<0.05).

Conclusion

Children with moderate AD have impaired sleep quality and lower melatonin levels compared to controls. No correlation was found between melatonin levels and CSHQ, as well as melatonin levels and SCORAD, although there was a strong and significant correlation between SCORAD and CSHQ. Therefore, melatonin levels may not be the main cause of sleep disturbances in children with moderate AD.

Phenotypic overlap between atopic dermatitis and autism

BACKGROUND

Autism, a childhood behavioral disorder, belongs to a large suite of diseases, collectively referred to as autism spectrum disorders (ASD). Though multifactorial in etiology, approximately 10% of ASD are associated with atopic dermatitis (AD). Moreover, ASD prevalence increases further as AD severity worsens, though these disorders share no common causative mutations. We assessed here the link between these two disorders in the standard, valproic acid mouse model of ASD. In prior studies, there was no evidence of skin involvement, but we hypothesized that cutaneous involvement could be detected in experiments conducted in BALB/c mice. BALB/c is an albino, laboratory-bred strain of the house mouse and is among the most widely used inbred strains used in animal experimentation.

METHODS

We performed our studies in valproic acid (VPA)-treated BALB/c hairless mice, a standard mouse model of ASD. Mid-trimester pregnant mice received a single intraperitoneal injection of either valproic acid sodium salt dissolved in saline or saline alone on embryonic day 12.5 and were housed individually until postnatal day 21. Only the brain and epidermis appeared to be affected, while other tissues remain unchanged. At various postnatal time points, brain, skin and blood samples were obtained for histology and for quantitation of tissue sphingolipid content and cytokine levels.

RESULTS

AD-like changes in ceramide content occurred by day one postpartum in both VPA-treated mouse skin and brain. The temporal co-emergence of AD and ASD, and the AD phenotype-dependent increase in ASD prevalence correlated with early appearance of cytokine markers (i.e., interleukin [IL]-4, 5, and 13), as well as mast cells in skin and brain. The high levels of interferon (IFN)γ not only in skin, but also in brain likely account for a significant decline in esterified very-long-chain N-acyl fatty acids in brain ceramides, again mimicking known IFNγ-induced changes in AD.

CONCLUSION

Baseline involvement of both AD and ASD could reflect concurrent neuro- and epidermal toxicity, possibly because both epidermis and neural tissues originate from the embryonic neuroectoderm. These studies illuminate the shared susceptibility of the brain and epidermis to a known neurotoxin, suggesting that the atopic diathesis could be extended to include ASD.