[The study on descriptive epidemiology of peptic ulcer in Hokkaido]

We previously reported that the reported that the ratio of gastric ulcer to duodenal ulcer in Hokkadio was higher than that in other area of Japan. This time, we analysed peptic ulcer cases of five hospitals in Hokkaido on the point of geographical and pathological distribution. When we divided these hospitals into two groups (in Sapporo city and other provincial areas) and calculated the sex and age adjusted ratio of gastric ulcer to duodenal ulcer in each group, we found the difference between the two groups (in Sapporo city: 2.26, other provincial area: 5.86) and thought the feature of high ratio the feature of the provincial hospitals. This difference in Hokkaido may be due to the environmental factors for peptic ulcer or the biased sampling of the study. The further study is needed to reveal the geographical and pathological distribution of this disease.