Prevalence of gastric cancer decreases with age in long‐living elderly in Japan, possibly due to changes in Helicobacter pylori infection status

OBJECTIVES: The prevalence of Helicobacter pylori (Hp) infection and the development of gastric cancer are both believed to increase with age in Japan. However, no studies have investigated people older than 65 years in detail. In this study, we investigated the prevalence of Hp infection and gastric cancer in the elderly, and analyzed the influence of both factors on longevity. METHODS: All patients investigated were 65 years old and over. A total of 1877 autopsy cases were used to investigate the prevalence of gastric cancer and colonic cancer. Serum samples were obtained from 644 patients with dyspepsia and analyzed for Hp-IgG antibodies. Of these 644 patients, 63 underwent upper gastrointestinal endoscopies. Five biopsies were obtained and evaluated for the following morphological variables: neutrophils, mononuclear cell, atrophy, and intestinal metaplasia. Hp infection was evaluated histologically and with the (13)C-urea breath test. RESULTS: The prevalence of gastric cancer was significantly lower in subjects older than 85 years. The positive rate of serum Hp-IgG, and Hp infection as detected histologically and by the (13)C-urea breath test, also decreased with age. In Hp(+) patients, the neutrophil score significantly decreased with age. In Hp(-) patients, however, the intestinal metaplasia score significantly increased with age. CONCLUSIONS: The non-infection of Hp itself is not related to longevity in Japanese elderly, because even Hp(-) patients appear to have been infected previously with Hp. The lower prevalence of gastric cancer in the elderly may be due to the disappearance of Hp colonization, which may contribute to longevity in Japanese elderly.