Getting to the Root of the Food Allergy "Epidemic"

Atopic dermatitis phenotype affects expression of atopic diseases despite similar mononuclear cell cytokine response

BACKGROUND

The atopic march refers to the coexpression and progression of atopic diseases in childhood, often beginning with atopic dermatitis (AD), although children may not progress through each atopic disease.

OBJECTIVE

We hypothesized that future atopic disease expression is modified by AD phenotype and that these differences result from underlying dysregulation of cytokine signaling.

METHODS

Children (n = 285) were enrolled into the Childhood Origins of Asthma (COAST) birth cohort and followed prospectively. Rates of AD, food allergy, allergic rhinitis, and asthma were assessed longitudinally from birth to 18 years of age. Associations between AD phenotype and food allergy, allergic rhinitis, asthma, allergic sensitization, exhaled nitric oxide, and lung function were determined. Peripheral blood mononuclear cell responses (IL-5, IL-10, IL-13, IFN-γ) to dust mite, phytohemagglutinin, Staphylococcus aureus Cowan I, and tetanus toxoid were compared among AD phenotypes.

RESULTS

AD at year 1 was associated with an increased risk of food allergy (P = .004). Both persistent and late-onset AD were associated with an increased risk of asthma (P < .001), rhinitis (P < .001), elevated total IgE (P < .001), percentage of aeroallergens with detectable IgE (P < .001), and elevated exhaled nitric oxide (P = .002). Longitudinal analyses did not reveal consistent differences in peripheral blood mononuclear cell responses among dermatitis phenotypes.

CONCLUSION

AD phenotype is associated with differential expression of other atopic diseases. Our findings suggest that peripheral blood cytokine dysregulation is not a mechanism underlying this process, and immune dysregulation may be mediated at mucosal surfaces or in secondary lymphoid organs.

Socioeconomic inequalities in 29 childhood diseases: evidence from a 1,500,000 children population retrospective study

BACKGROUND

Socioeconomic position (SEP) powerfully affects health status in the childhood population. However, the knowledge of which diseases are more affected by SEP and whose outcomes could be improved by having a more equitable society remains uncertain on a population basis.

METHODS

We measured socioeconomic and gender inequalities in the pre-COVID-19 era for 29 diseases in the entire childhood population in Catalonia to identify which diseases are most impacted by inequalities. This population-based study included 1,449,816 children under 15 years old from 2014 to 2017 (48.52% girls) and each of their registered diagnoses within the Catalonia National Health System. We calculated frequency measures by SEP and their sex ratios for each disease. We estimated four regression-based inequality measures: slope index of inequality, relative index of inequality (RII), absolute population-attributable fraction, and population-attributable fraction.

RESULTS

Twenty-five of the 29 diseases examined showed SEP inequalities. The diseases with the greatest inequalities in both sexes were tuberculosis, obesity, adjustment and anxiety disorders, essential hypertension, poisoning, short gestation, low birth weight, foetal growth retardation and intrauterine hypoxia and birth asphyxia and trauma (RII ≥ 2.0); only food allergy showed the opposite pattern (RII < 1.0). Overall, 80,188 (7.80%) of the disease events in boys and 74,921 (8.88%) in girls would be avoided if all children had the same disease rate as those in the medium-high SEP group, with tuberculosis, intrauterine hypoxia and birth asphyxia and trauma, obesity, and short gestation, low birth weight, foetal growth retardation being those that could be reduced the most in relative terms, and dermatitis, injuries, acute bronquitis, and being overweight those that could be reduced the most in absolute terms. Girls present higher RII than boys for respiratory allergy, asthma, dermatitis, being overweight, and obesity (p < 0.05). In contrast, boys showed higher RII compared to girls only in congenital anomalies (p < 0.05).

CONCLUSIONS

Socioeconomic and gender inequalities are widely present in childhood health. This indicates that SEP plays a common role in their development although it varies in magnitude according to each disease. It is also a phenomenon that comprises all SEP groups in society. Action needs to be taken to ensure a fairer start in life in terms of health.

The Unmet Needs of Patients with Food Allergies

This article reviews the unmet needs of patients with food allergies. Anxiety is common among patients with food allergies and their caregivers, which naturally stems from the avoidance, exposure, and uncertainty involved in care. Anxiety associated with allergen avoidance can have both adaptive and detrimental effects on overall health. Anxiety has implications for transitioning the responsibility of health and well-being from caregivers to the patients. As more children with food allergies become adults with food allergies, this will be an urgent topic. Moreover, as more exposure-based therapies become available, understanding patients' psychological expectations and experiences of exposure is vital.