Exposure to pets and the association with sensitization and allergic disease in Belgian schoolchildren.

Prolonged domestic exposure, from birth on, to dog allergen may protect against sensitization.

Body mass index in Belgian schoolchildren and its relationship with sensitization and allergic symptoms.

Results of studies of the influence of body mass index (BMI) on the allergic status are controversial. As a part of the Aalst Allergy Study, we assessed the prevalence of the different BMI categories (underweight, normal weight, overweight, and obesity) and a possible association between BMI and atopy in 1576 unselected Belgian schoolchildren, aged from 3.4 to 14.8 yr. BMI was used to determine weight status. Skin prick testing with the most common aeroallergens was performed. A parental questionnaire documented data on respiratory and allergic disorders, demographic characteristics and other potential risk factors for sensitization. Among the total children, 4.1% of the children were underweight, 14.5% were overweight, and 7.4% were obese. More girls than boys were overweight (p = 0.015). In the group of children older than 12 yr, we found more overweight (p = 0.03) and obese (p = 0.004) girls, and more obese boys (p = 0.004) than in the younger age groups. In contrast with reports in the literature, an increased prevalence of allergic sensitization in underweight girls only [adjusted odd ratio (OR(adj)) = 2.9, 95% confidence interval (CI): 1.3-6.4] was documented. A strong association between obesity and exercise-induced respiratory symptoms was found in both boys (OR(adj) = 14.5, 95% CI: 2.9-73.3) and girls (OR(adj) = 4.9, 95% CI: 1.3-17.4). No correlations with allergic respiratory symptoms, eczema, or rhinoconjunctivitis could be documented.

The influence of bedroom environment on sensitization and allergic symptoms in schoolchildren.

BACKGROUND: Bedroom conditions have been associated with an increased risk of allergy. OBJECTIVE: The aim of this study was to evaluate the relationship between sleeping environment and sensitization and allergic symptoms in schoolchildren. METHODS: A cross-sectional study, the Aalst Allergy Study, was performed in an unbiased community population of 2021 Belgian schoolchildren, aged 3.4 to 14.8 years. Skin prick testing was performed with the most common aeroallergens and bedroom conditions (presence of stuffed toys, type of flooring, and bedding material) were documented through a parental questionnaire. RESULTS: The presence of stuffed toys in the bedroom was associated with a lower prevalence of overall sensitization and a lower prevalence of conjunctivitis and allergic respiratory symptoms. That effect was almost exclusively present in children with a positive family history of atopy and was more pronounced as the number of stuffed toys increased. A significantly lower prevalence of overall sensitization, sensitization to house dust mite, and wheezing was documented in children with nonsynthetic bedding materials. That effect was exclusive to children with a positive family history of atopy. Type of flooring was not associated with sensitization or allergic symptoms. CONCLUSION: Our data suggest that bedroom exposure to stuffed toys and nonsynthetic bedding materials may have a protective effect against sensitization and allergic symptoms in genetically predisposed children. Confirmation of these findings will require further prospective studies that include measurement of levels of mite allergens and endotoxins and assessment of the time, degree, and duration of the exposure.