HELICOBACTER-PYLORI ANTIBODIES IN RELATION TO PRECANCEROUS GASTRIC-LESIONS IN A HIGH-RISK CHINESE POPULATION

Helicobacter pylori infection is a major cause of gastritis and may be a key risk factor for stomach cancer, but its role in the process of gastric carcinogenesis is not well understood. Herein, we examine H. p ylori prevalence in relation to demographic and lifestyle factors and to severity of precancerous lesions in an area of China with one of th e highest rates of stomach cancer in the world. H. pylori serum IgG an tibody positivity was assayed among 2646 adults, ages 35-64, participa ting in a population-based gastroscopic screening survey in the high-r isk area. The prevalence of positivity was evaluated according to gast ric histology, environmental and lifestyle variables determined by int erviews during the screening, and level of serum pepsinogens. The odds of advanced precancerous lesions (intestinal metaplasia and dysplasia ) of the stomach among those with antibody positivity were estimated b y logistic regression. Seventy-two % of the population was H. pylori a ntibody-positive, with nonsignificant variation by sex, age, income, e ducation, family size, and cigarette smoking habits. H. pylori positiv ity was higher among those who ate sour pancakes, a fermented indigeno us staple that is a risk factor for gastric dysplasia and stomach canc er in this population. The prevalence of H. pylori varied most notably , however, with gastric pathology. The percent of H. pylori positivity increased from 55 to 60 to 87% among those with superficial (nonatrop hic) gastritis, mild chronic atrophic gastritis, and severe chronic at rophic gastritis, respectively, before falling to 78% among those with intestinal metaplasia or dysplasia. H. pylori antibody positivity als o was strongly correlated with serum pepsinogen concentrations, partic ularly pepsinogen II, but knowledge of H. pylori status did not marked ly improve serological identification of advanced precancerous lesions above that provided by pepsinogen ratios alone. The findings suggest that H. pylori infection contributes to the process of gastric carcino genesis, particularly during the early stages, in this high-risk area.