Epidemiology Helicobacter pylori infection in children in the Tyva Republic (Russia)

Background Tyva Republic is a small mountainous area at the geographical center of Asia in southern Siberia, with a high incidence of gastric cancer. Aim: We examined the prevalence of H. pylori and associated risk factors among children in Tyva. Methods: Cross-sectional study was conducted among Tuvan children who had upper gastrointestinal symptoms and underwent upper gastroscopy with gastric biopsies. Informed consent was obtained from the parents and assent from the children. Demographic information, ethnicity, parents' education and employment status, and family size were collected. H. pylori infection was diagnosed by histologic examination. Results: There were 270 children between the ages 7 and 17 years (mean 13.4 +/- 2.7); 64% girls; 147e Tuvan and 123 Caucasians. The overall prevalence of H. pylori was high and similar between boys and girls (55 vs. 57%, respectively, p = 0.42). The infection was highest in Tuvan children (67%. vs. 43%, respectively (OR = 2.4; 95%CI = 1.9.4-3), p = 0.05. H. pylori prevalence increased with age from 44% among 7 to 10 years and 64% among those 14 to 17 (OR = 3.0; 95%CI = 1.6-5.8), p = 0.0.005; the pattern was consistent among both ethnic groups. The prevalence of the infection among Caucasian children was inversely correlated with the level of mother's education (44%, vs. 61%) (i.e., for with and without a college education the OR = 2.3; 95%CI = 1.2-3.7), p = 0.02. Neither the total number of children nor adults living in the same household correlated with H. pylori prevalence. Conclusions: Strategies to reduce the incidence of gastric cancer in Tyva will need to start in childhood.