Attributable risk of H. pylori in peptic ulcer disease - Does declining prevalence of infection in general population explain increasing frequency ofnon-H. pylori ulcers?

Recent reports in the United States have found that fewer peptic ulcers are due to Helicobacter pylori than previously believed. The aim of this study is to determine if the declining prevalence of H. pylori infection in the general population can account for the apparent increase in the frequency o f non-H. pylori ulcers. A total of 396 patients with peptic ulcer or ulcer scar were enrolled in this study. The pre-1950 population consisted of 149 patients with gastric ulcers and with 44 duodenal ulcers. The post-1950 pop ulation consisted of 96 patients with gastric ulcers and 107 with duodenal ulcers. The frequency of H. pylori-negative gastric ulcers was 5.4% in pati ents born before 1950 and 4.2% in patients born after 1950, and the frequen cy of H, pylori-negative duodenal ulcers was 0% and 1.9%, respectively. The re are no statistical differences between the two populations in gastric an d duodenal ulcers. H. pylori seropositivity was 74.9% in asymptomatic volun teers born before 1950 and 20.7% in those born after 1950 (P < 0.01) in the general population. The attributable risk of H. pylori infection in peptic ulcer diseases was not affected by the prevalence of H. pylori infection i n the general population in Japan. This suggests that the apparent increase in frequency of non-H, pylori ulcers in the United States is not simply du e to the declining prevalence of infection. Other explanations for non-H. p ylori ulcers should be sought.