Retrospective Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 21, 2021; 27(27): 4441-4452
Published online Jul 21, 2021. doi: 10.3748/wjg.v27.i27.4441
Recent trends in the prevalence and distribution of colonic diverticula in Japan evaluated using computed tomography colonography
Noriyuki Isohata, Koichi Nagata, Kenichi Utano, Ryoichi Nozaki, Satoshi Nozu, Takashi Kato, Shigeyoshi Kijima, Hiroshi Matsumoto, Kenichiro Majima, Yasuji Ryu, Michiaki Hirayama, Shungo Endo
Noriyuki Isohata, Shungo Endo, Department of Coloproctology, Fukushima Medical University, Aizu Medical Center, Aizuwakamatsu 969-3492, Fukushima, Japan
Koichi Nagata, Department of Gastroenterology, Fukushima Medical University, Fukushima 960-1295, Fukushima, Japan
Kenichi Utano, Department of Radiology, Fukushima Medical University, Aizu Medical Center, Aizuwakamatsu 969-3492, Fukushima, Japan
Ryoichi Nozaki, Department of Gastroenterology, Takano Hospital, Coloproctology Center, Kumamoto 862-0971, Kumamoto, Japan
Satoshi Nozu, Department of Radiology, Saitama Cancer Center, Ina 362-0806, Saitama, Japan
Takashi Kato, Department of Gastroenterology, National Hospital Organization Hokkaido Medical Center, Sapporo 063-0005, Hokkaido, Japan
Shigeyoshi Kijima, Department of Radiology, Jichi Medical University, Shimotsuke 329-0498, Tochigi, Japan
Hiroshi Matsumoto, Division of Gastroenterology, Kawasaki Medical School Hospital, Kurashiki 701-0192, Okayama, Japan
Kenichiro Majima, Department of Health Management, Kameda Medical Center, Kamogawa 296-8602, Chiba, Japan
Yasuji Ryu, Department of Radiology, Tonami General Hospital, Tonami 939-1395, Toyama, Japan
Michiaki Hirayama, Department of Gastroenterology, Tonan Hospital, Sapporo 060-0004, Hokkaido, Japan
Author contributions: Planning and conducting the study was performed by Endo S, Isohata N and Nagata K; Data collection was performed by Nagata K; Radiological interpretation of data was performed by Nagata K, Utano K, Nozaki R, Nozu S, Kato T, Kijima S, Matsumoto H, Majima K, Yasuji R and Hirayama M; Drafting the manuscript was performed Isohata N; all authors critically revised the report, commented on drafts of the manuscript, and approved the final report.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Fukushima Medical University Hospital.
Informed consent statement: Participants were not required to give informed consent to this study because the analysis used anonymous clinical data that were obtained after each participant agreed to treatment by written consent.
Conflict-of-interest statement: We have no financial relationship to disclosure.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Noriyuki Isohata, MD, PhD, Assistant Professor, Department of Coloproctology, Fukushima Medical University, Aizu Medical Center, 21-2 Maeda, Tanisawa, Kawahigashi-Machi, Aizuwakamatsu 969-3492, Fukushima, Japan.
Received: April 27, 2021
Peer-review started: April 27, 2021
First decision: May 27, 2021
Revised: June 6, 2021
Accepted: July 9, 2021
Article in press: July 9, 2021
Published online: July 21, 2021
Research background

Colonic diverticulosis is a common abnormality of the colon. The prevalence of diverticulosis and diverticular disease in Japan is increasing due to aging and a westernized diet.

Research motivation

Recent trends in the prevalence and distribution of colonic diverticula in Japan are not clear. Most recent studies on diverticulosis in Japan involved the use of colonoscopy. In recent years, computed tomography colonography (CTC) has been widely used as an alternative colon cancer screening method. We considered CTC to detect diverticula as outpouchings of the colonic wall from a more advantageous perspective, and it may be superior to colonoscopy and barium enema for detecting diverticula.

Research objectives

The main objective of this study was to evaluate the prevalence and distribution of colonic diverticula in Japan.

Research methods

This study included 1181 participants from 14 hospitals in Japan. We analyzed the prevalence and distribution of colonic diverticula and their relationships with age and sex using CTC and analyzed the relationship between the diverticula and the length of the large intestine.

Research results

Diverticulosis was present in 48.1% of the participants. The prevalence of diverticulosis was higher in the older participants. The diverticula seen in younger participants were predominantly located in the right-sided colon and on the bilateral side for older participants. The length of the large intestine with multiple diverticula in the sigmoid colon was significantly shorter in those without diverticula.

Research conclusions

The prevalence of colonic diverticulosis in Japan is 48.1%. This was much higher than that previously reported. In older participants, the prevalence was higher, and the distribution tended to be bilateral.

Research perspectives

The data used in this study were slightly limited and a bit out of date. We hope to perform a large-scale prospective study after standardization of bowel preparation and imaging protocols, and CTC use will become widespread in the future. We also hope to determine the relationship between the trends in diverticulosis and its accompanying symptoms.