Liquid-containing Refluxes and Acid Refluxes May Be Less Frequent in the Japanese Population Than in Other Populations: Normal Values of 24-hour Esophageal Impedance and pH Monitoring.
- Author:
Osamu KAWAMURA
1
;
Yukie KOHATA
;
Noriyuki KAWAMI
;
Hiroshi IIDA
;
Akiyo KAWADA
;
Hiroko HOSAKA
;
Yasuyuki SHIMOYAMA
;
Shiko KURIBAYASHI
;
Yasuhiro FUJIWARA
;
Katsuhiko IWAKIRI
;
Masahiko INAMORI
;
Motoyasu KUSANO
;
Micho HONGO
Author Information
- Publication Type:Multicenter Study ; Original Article
- Keywords: 24-hour esophageal impedance and pH monitoring; Gastroesophageal reflux; Japanese population; Normal values; Proximal reflux
- MeSH: Asian Continental Ancestry Group*; Electric Impedance*; Esophagus; Gastroesophageal Reflux; Healthy Volunteers; Humans; Hydrogen-Ion Concentration*; Male; Reference Values*
- From:Journal of Neurogastroenterology and Motility 2016;22(4):620-629
- CountryRepublic of Korea
- Language:English
- Abstract: BACKGROUND/AIMS: Twenty-four-hour esophageal impedance and pH monitoring allows detection of all types of reflux episodes and is considered the best technique for identifying gastroesophageal refluxes. However, normative data for the Japanese population are lacking. This multicenter study aimed to establish the normal range of 24-hour esophageal impedance and pH data both in the distal and the proximal esophagus in Japanese subjects. METHODS: Forty-two healthy volunteers (25 men and 17 women) with a mean ± standard deviation age of 33.3 ± 12.4 years (range: 22–72 years) underwent a combined 24-hour esophageal impedance and pH monitoring. According to the physical and pH properties, distal or proximal esophageal reflux events were categorized. RESULTS: Median 45 reflux events occurred in 24 hours, and the 95th percentile was 85 events. Unlike previous reports, liquid-containing reflux events are median 25/24 hours with the 95th percentile of 62/24 hours. Acidic reflux events were median 11/24 hours with the 95th percentile of 39/24 hours. Non-acidic gas reflux events were median 15/24 hours with the 95th percentile of 39/24 hours. Proximal reflux events accounted for 80% of the total reflux events and were mainly non-acidic gas refluxes. About 19% of liquid and mixed refluxes reached the proximal esophagus. CONCLUSIONS: Unlike previous studies, liquid-containing and acidic reflux events may be less frequent in the Japanese population. Non-acidic gas reflux events may be frequent and a cause of frequent proximal reflux events. This study provides important normative data for 24-hour impedance and pH monitoring in both the distal and the proximal esophagus in the Japanese population.
