Сравнительная распространенность атопической сенсибилизации на приграничных территориях двух государств Россия и Финляндия.

In recent decades, there has been a widespread increase allergic pathology. The influence of the environment on its development is very great. The natural environment through epigenetic mechanisms has a beneficial effect and prevents the development of allergic diseases. A study of the prevalence of allergic diseases and atopic sensitization in two adjacent areas of Russia and Finland has been conducted for many years. Allergic diseases and atopic sensitization are more common in Finland. With many years of observation, these trends persist. In this study, we evaluated atopic sensitization in two samples living in identical climatic and geographical areas. The prevalence of individuals with elevated levels of total IgE, total food and  inhaled IgE was estimated, the spectrum of atopic sensitization to 8 inhaled allergens was studied: timothy grass, birch, wormwood, Cladosporia grass, horse, cat, dog and house dust mite - Dermatophagoides  pteronyssinus and food allergens: cow's milk, chicken egg, fish, soy, wheat and peanut. The measurement was performed using the Phadiatop® RAST for inhalation and food allergens (UniCAP 1000 v.2; Pharmacia Upjohn, Uppsala, Sweden). Cut-off: total IgE ≥ 110 kUA / l and sIgE ≥ 2.5 kUa / l and 0.35 kUA / l. The study included 2 stages - 2003 and 2010/2012 - Finland / Russia. In 2003, children 7–15 years old from Finland (n = 344) and from the Republic of Karelia (n = 427) were randomly included. Stage 2 includes participants who evaluated the level of IgE in 2003, total 180: Finns, n = 98 (38 boys and 60 girls), Russians, n = 82 (39 boys and 43 girls). The study protocol was approved by the ethics committee of the Central Hospital of Helsinki University, Petrozavodsk State University, and all participants received written informed consent. Results. In Finland, the prevalence of increased IgE is higher in 2003 and 2010/2012. In dynamics - a slight decrease in the prevalence of total IgE in two cohorts. The prevalence of increased inhaled sIgE in 2003 and 2010/2012 is statistically significantly higher among Finns, p = 0.019 and p = 0.027. In dynamics, the growth of this atopic sensitization in the two studied cohorts. An increased food sIgE in 2003 was more common among Finns than among Russians (27.6% and 18.3%), p = 0.142. In 2010/2012 the prevalence of food sensitization decreased by 2 times among Finns and 3 times among Russians  In Russia in 2003, the high level of sensitization was found for house dust mitе and cat, followed by timothy, birch and dog. At stage 2, an increase in sensitization was noted. This is most pronounced in relation to timothy - an almost 2-fold increase to 12.2% (5.0; 19.4), p = 0.176, 2-fold wormwood - up to 7.3% (1.6; 13.1 ), p = 0.312, horses 2 times - up to 2.4% (0.0; 5.8), p = 0.563, dogs 1.5 times - up to 7.3% (1.6; 13.1 ), p = 0.521 house dust mites 1.5 times - up to 22% (12.8; 31.1), p = 0.220. In Finland, in 2003, sensitization to a dog prevails - 26.5%, timothy - 24.5%, birch-20.4% and cat - 20.4%. In 2010, there was an increase in sensitization to inhalant allergens, mainly to the house dust mite - it increases almost 2 times from 8.2% to 19.4% (p = 0.023), and hors increase more than 2 times, from 5.1% to 13.3% (p = 0.047). When researching food sIgE, differences between the study groups were also identified. In Russia, in 2003, atopy for egg , cow's milk and wheat prevailed; in the dynamics there was a tendency to its decrease. In Finland, the greatest sensitization was detected for cow's milk, nut, wheat and egg; in the dynamics it also decreases. Interestingly, at both stages of the study, no sensitization to fish was detected among Russians and Finns. A statistically significant difference in sensitization between groups was achieved only for peanut and cow's milk in 2003. At the 2nd stage of the study, there was a decrease in sensitization to food allergens, mainly on the Finnish side. Thus, the differences in atopic sensitization that developed in childhood persisted between the examined populations of Finnish and Russian Karelia after 7–9 years.