Risk factors for respiratory symptoms and atopic sensitisation in the Baltic area.

Abstract

Recent studies have indicated that atopic sensitisation is uncommon while respiratory symptoms are common among schoolchildren in Eastern Europe. Risk factors for respiratory symptoms and atopic sensitisation were evaluated in a cross sectional study involving 2594 schoolchildren (10-12 years) from Sweden (n=665), Poland (n=410), and Estonia (n= 1519). The measurements included parental questionnaires and skin prick tests with eight standardised allergens. Multiple logistic analyses demonstrated that atopic heredity was a significant independent risk factor for respiratory symptoms and atopic sensitisation in all the countries. Current dampness and maternal smoking were related to respiratory symptoms whereas domestic crowding, male gender, and passive smoking during infancy were related to atopic sensitisation. Current maternal smoking had a strong dose response association with current coughing attacks (nocturnal cough >4 weeks or exercise induced coughing attacks) but only in Eastern Europe. A strong inverse relationship was recorded between domestic crowding and sensitisation as the risk for sensitisation increased with decreasing number of persons per room in the household (odds ratio (OR) 0.58, 95% confidence interval (CI) 0-43 to 0.77). Exposure to tobacco smoke at home during infincy was a risk factor for atopic sensitisation but only to animal dander and only in Eastern Europe (OR 1I41, 95% CI 1-03 to 1-93). In conclusion, there were small differences in the pattern of risk factors between Eastern and Western Europe. The only exception was environmental tobacco smoke being a risk factor only in Eastern Europe. The study also suggests that factors related to domestic crowding protect against atopic sensitisation in Estonia and Poland. A higher standard of living with less crowding may give rise to an increasing prevalence of atopic sensitisation also in Eastern Europe. (Arch Dis Child 1995; 72: 487-493)

Adverse reactions to food and food allergy in young children in Iceland and Sweden

“…It is possible that the prevalence of food intolerance and allergy among young children is not subject to as large geographic variations as respiratory allergies in older children and young adults. This suggestion would be supported by the similar prevalence of positive skin prick tests to egg and milk in Estonian and Swedish infants (23), despite the much lower prevalence of respiratory allergy among older children in Estonia and other former socialist countries in Eastern Europe (24).…”

Environment and infant immunity

“…The gut flora is quantitatively the most important source of microbial stimulation, and may provide a primary signal for driving the postnatal maturation of the immune system, thus inducing Th1-like immunity (Rook & Stanford, 1998). We have recently reported considerable differences in the composition of the gut flora of healthy 1-year-old infants in Estonia (which has a low prevalence of allergy; Bråbäck et al 1995), and Sweden (Sepp et al 1997). For example, lactobacilli and eubacteria were more common and the counts were higher in Estonian infants than in Swedish infants, whereas the reverse was true for Clostridium difficile.…”

Is the increase in asthma prevalence linked to increase in allergen load?

“…Migrants who go from villages to towns have more asthma (55,56); asthma is less prevalent in crowded conditions (57); and asthma is very rare in populations with traditional, nonaffluent lifestyles (15,58).…”