Time series analysis of gastric acid secretion over a 20-year period in normal Japanese men

Abstract

Considering that gastric acid secretion remained unchanged in H. pylori-negative Japanese men over a 20-year period at a level much lower than that in Occidental subjects, upper gastrointestinal disease profiles in the Japanese population will differ from those in Western countries in the post-H. pylori era.

A Chronological Increase in Gastric Acid Secretion from 1995 to 2014 in Young Japanese Healthy Volunteers under the Age of 40 Years Old

“…This finding contrasts with our recent report in which gastric acid secretion did not change during the same period in H. pylori-negative asymptomatic outpatients with a mean age of 63 years (Iijima et al 2015). Moreover, in that study, an additional subgroup analysis in 47 H. pylori-negative outpatients over the age of 65 reveals that there is no change in gastric acid secretion between 1995 and 2014 (r = 0.03, p = 0.83).…”

“…In this study, we applied the same definition of the chronological periods as in our preceding study (Iijima et al 2015) so as to help compare the difference between the two studies.…”

“…These healthy volunteers had been recruited mainly from Tohoku university students or post-graduate students, and they were not included in our preceding report comprising hospital outpatients (Iijima et al 2015). Among them, 88 young subjects under the age of 40 with a mean age of 26 (5) were extracted for the present analysis.…”

“…Meanwhile, we recently reported that gastric acid secretion levels were unchanged from the 1990s to 2010s in H. pylori-negative asymptomatic Japanese outpatient subjects with a mean age of 63 years old (Iijima et al 2015). However, because the lifestyle of young people in Japan is quite different from that of elderly people in areas such as dietary pattern, it is worth investigating chronologic changes in gastric acid secretion in the young generation.…”

Mucosal breaks show same circumferential distribution in majority of patients with recurrent reflux esophagitis

“…Studies conducted in the 1990 s of Japanese subjects showed that gastric acid secretion levels increased from the 1970 s to 1990 s, though they remained lower as compared to Europeans and North Americans 19 20 21. In addition, those levels have not increased over the past 2 decades in Japanese 22 23. These factors may be related to the lower prevalence of GERD in Asian individuals as compared to Western populations.…”