Helicobacter pylori infection progresses proximally associated with pyloric metaplasia in age-dependent tendency: a cross-sectional study

BACKGROUND: The elderly population presents higher morbidity of H. pylori associated diseases in proximal stomach. The specific pathogenesis and mechanism have not been clearly addressed. The gastric environment for H. pylori colonization is dynamic with increasing age. The aim of present study is to investigate the correlation among the distribution of H. pylori, mucosal inflammation, gastric microenvironment and age. METHODS: A total of 180 patients with dyspepsia symptoms were divided into young, middle-aged and elderly groups. Biopsies were obtained from each patient in five locations: great curvature (mid-corpus, mid-antrum), lesser curvature (mid-corpus, mid-antrum) and incisura angularis (IA), analyzed for H. pylori density, mucosal inflammation and histopathology. RESULTS: The infection rate of H. pylori increased linearly with age (p < 0.001) in corpus, but not in antrum and IA. The H. pylori density was significantly aggravated in IA (p = 0.002) and corpus (p < 0.001) in elderly patient, but not in antrum. The mucosa inflammation scores were consistent with the severity of H. pylori colonization among three age groups. In elderly patients, the pyloric glands present more frequently in corpus, comparing with young and middle-aged group. A significant positive correlation among aggravating severity of H. pylori infection, mucosal inflammation and pyloric metaplasia in corpus with increasing age (p < 0.001) was occurred. CONCLUSIONS: With increasing age, both topographic distribution of H. pylori and the expansion of pyloric glands increased in a distal-to-proximal gastric direction. Pyloric metaplasia in corpus was correlated with the risk of aggravated H. pylori colonization and associated inflammation in elderly population.