疫学からみた胃潰瘍発生の背景

The Background of Occurrence of Gastric Ulcer from the Viewpoint of Epidemiology

　種々な場合に観察された胃潰瘍の頻度を，そのまま発生率に短絡したようなものは別として，胃潰瘍の発生自体が疫学的考察の対象となったことは極めてまれである．筆者は先に胃潰瘍の疫学について若干の私見を報告したが^1)～3)，その中でも発生の問題についてはほとんど触れるところがなかった．この小論文は，いわば，その追加報告である．

　胃潰瘍の治癒と治癒率

　胃潰瘍の自然発生率を観察することは不可能事で，当然ながら直接的な資料はない．観察しうる種々な“場合の頻度”を援用して推論を試みるほかはないと思われる．

　An epidemiological research was conducted concerning occurrence of gastric ulcer. From the fact that its rate of affection remains constant in number, it was hypothesized that the cure rate and occurrence rate are on the average. Also, the natural cure rate was one month, 7.5% and the occurrence rate in Japanese people was 1.84% per year. Among these, the first occurrence of ulcer was 0.24%, recurrent ulcer 1.60%, and the ratio of recurrent to occurrence rate was 87%. That is, comparing the 19.1% of natural recurrence with 10.0% of recurrent ulcer in clinical research, it was observed that clinically, one half of the recurrence of ulcer could be controlled. Moreover, considering it by age and sex groups, it was discovered that the rate of occurrence in gastric ulcer is higher in higher age groups and sex does not make any difference. This is contrary to existing findings.

　The subject of occurrence in the epidemiology of gastric ulcer is an essential area to investigated,yet much of it is still to be elucidated. Thus, further discussion is required in the future in this area.