Asthma and allergy in Russian and Norwegian schoolchildren: results from two questionnaire-based studies in the Kola Peninsula, Russia, and northern Norway.

BACKGROUND

Previous studies have shown that the prevalence of asthma and allergy in children is lower in Eastern than Western Europe.

METHODS

We have compared the prevalence of asthma, respiratory symptoms, allergic rhinoconjunctivitis, and atopic dermatitis in schoolchildren aged 7-13 years in a questionnaire-based study conducted in the city of Nikel on the Kola Peninsula, Russia, in 1994 (n = 1143) and another conducted in northern Norway in 1995 (n = 8676).

RESULTS

The prevalence of diagnosed asthma was 5.1% in Russian children and 8.6% in Norwegian children; RR =0.58 (95% CI: 0.44-0.76). The prevalence of all respiratory symptoms was higher in Russian children. The prevalence of allergic rhinoconjunctivitis was 16.9%, in Russian children and 22.1%, in Norwegian children: RR =0.74 (95% CI: 0.65-0.85). The prevalence of atopic dermatitis was 7.4% in Russian children and 19.7% in Norwegian children; RR=0.38 (95% CI: 0.31-0.46).

CONCLUSIONS

We conclude that the prevalence of diagnosed asthma, allergic rhinoconjunctivitis, and atopic dermatitis was higher in Norwegian than Russian schoolchildren. The higher prevalence of respiratory symptoms in Russian children probably reflects a higher prevalence of undiagnosed, nonallergic asthma.