Association of pollution and climate with atopic eczema in US children

BACKGROUND

We sought to determine the relationship between childhood eczema, climate, and environmental pollutants.

METHODS

We analyzed data from the 2007-2008 National Survey of Children's Health including a representative sample of 91,642 children age 0-17 years and the 2006-2007 Environmental Protection Agency measurements of carbon monoxide (CO), nitrate (NO3 ), nitrogen dioxide (NO2 ), organic carbon (OC), sulfate (SO3 ), sulfur dioxide (SO2 ), particulate matter ≤2.5 μm (PM-2.5) and <10 μm (PM-10), and tropospheric ozone levels, and the National Climate Data Center measurements of relative humidity (%), issued UV index, outdoor air temperature, and precipitation levels.

RESULTS

In multivariate survey logistic regression models controlling for age, sex, race/ethnicity, household income, US birthplace, and history of moving to a new location, eczema was associated with higher mean annual NO2 (p = 0.008), SO2 (p = 0.006), SO3 (p = 0.0002), arsenic (p = 0.0007), nickel (p = 0.0002), lead (p = 0.03), vanadium (p < 0.0001), and zinc (p = 0.003), but lower NO3 (p = 0.002), OC (p = 0.03), PM-2.5 (p = 0.006), cadmium (p < 0.0001), copper (p = 0.004), and potassium (p < 0.0001). In contrast, moderate-severe eczema was associated with higher NO3 (p = 0.03), OC (p = 0.008) and PM-2.5 (p = 0.01), copper (p = 0.04), lead (p = 0.008), and zinc (p = 0.01), but lower CO (p = 0.03). Principal component analysis was used and identified 4 combinations of pollutants and climate factors occurring in the USA, of which 1 was associated with higher prevalence and two were associated with lower prevalences of eczema (p < 0.05).

CONCLUSIONS

Pollutants in conjunction with climate factors may differentially impact eczema prevalence and severity, some with apparent harmful effects.

Association between severe eczema in children and multiple comorbid conditions and increased healthcare utilization

BACKGROUND

Atopic dermatitis (AD) is associated with multiple comorbid conditions, such as asthma and food allergy. We sought to determine the impact of eczema severity on the development of these disorders and other non-atopic comorbidities in AD.

METHODS

We used the 2007 National Survey of Children's Health, a prospective questionnaire-based study of a nationally representative sample of 91,642 children aged 0-17 yr. Prevalence and severity of eczema, asthma, hay fever and food allergy, sleep impairment, healthcare utilization, recurrent ear infections, and visual and dental problems were determined.

RESULTS

In general, more severe eczema is correlated with poorer overall health, impaired sleep, and increased healthcare utilization, including seeing a specialist, compared with children with mild or moderate disease (Rao-Scott chi-squared test, p < 0.0001). Severe eczema was associated with a higher prevalence of comorbid chronic health disorders, including asthma, hay fever, and food allergies (p < 0.0001). In addition, the severity of eczema was directly related to the severity of the comorbidities. These associations remained significant in multivariate logistic regression models that included age, sex, and race/ethnicity. Severe eczema was also associated with recent dental problems, including bleeding gums (p < 0.0001), toothache (p = 0.0004), but not broken teeth (p = 0.04) or tooth decay (p = 0.13).

CONCLUSIONS

These data indicate that severe eczema is associated with multiple comorbid chronic health disorders, impaired overall health, and increased healthcare utilization. Further, these data suggest that children with eczema are at risk of decreased oral health. Future studies are warranted to verify this novel association.