Related Experiment Video
Updated: Jan 30, 2026

Surgical Models of Gastroesophageal Reflux with Mice
Published on: August 25, 2015
Sex Differences in the Relation between Waist Circumference within the Normal Range and Development of Reflux
Hyo-Joon Yang1, Yoosoo Chang2,3,4, Soo-Kyung Park5
1Division of Gastroenterology, Department of Internal Medicine and Gastrointestinal Cancer Center, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, 03181, Korea. hyojoon.yang@samsung.com.
Abstract:
We examined the association of abdominal obesity and waist circumference within normal range with the incidence of reflux esophagitis, separately in men and women. This cohort study involved 142,679 Korean adults without reflux esophagitis, who underwent upper endoscopy at baseline and during follow-up. Waist circumference was categorized into the following quartiles: <80, 80.1⁻85, 85.1⁻90, and ≥90.1 cm in men; and <69.3, 69.3⁻74, 74.1⁻79.5, and ≥79.6 cm in women. During the 551,877.8 person-years of follow-up, 29,509 participants developed reflux esophagitis. The association between waist circumference quartiles and risk of reflux esophagitis significantly differed with sex (p for interaction < 0.001). In men, multivariable-adjusted hazard ratios (HRs) (95% confidence intervals (CIs)) comparing waist circumference quartiles 2, 3, and 4 to the lowest quartile were 1.03 (0.99⁻1.07), 1.08 (1.04⁻1.12), and 1.15 (1.10⁻1.19), respectively. In women, HRs (95% CIs) comparing quartiles 1, 2, and 4 to the 3rd quartile were 1.10 (1.04⁻1.17), 1.03 (0.98⁻1.10), and 1.07 (1.01⁻1.13), respectively. In this large cohort with endoscopic follow-up, the risk of reflux esophagitis increased with increasing waist circumference even within the normal range in men, whereas the risk increased with low normal waist circumference or with abdominal obesity in women, indicating a U-shaped association.
Related Concept Videos
Variation: Normal Distribution, Range, and Standard Deviation
Range
15.9; 16.1; 15.2; 14.8; 15.8; 15.9; 16.0; 15.5
Measurements of the amount of soda in a 16-ounce can vary since different subjects record these measurements or since the exact amount - 16 ounces of liquid, was not...
Sex-linked Disorders
Esophageal Varices-I: Introduction
Normal Stress
When a rod is under axial loading, the internal forces and corresponding stress are normal to the plane of the section, so it is termed normal stress. It's important to...
Normal Distribution

