Acid Gastro-Oesophageal Reflux and Oesophageal Pressure Activity during Postprandial and Nocturnal Periods: A Study in Subjects with and without Pathologic Acid Gastro-Oesophageal Reflux

Abstract

The aim of the investigation was to evaluate the relative quantity of acid gastro-oesophageal reflux during different time periods in subjects with and without pathologic rcflus. Twenty duodenal ulcer patients. 10 with and 10 without pathologic acid gastro-oesophageal reflux. and 26 asymptomatic volunteers were subjectcd to 12 h of simultaneous monitoring of pH and pressure activity in the oesophagus. The monitoring period was divided into a 3-h postprandial period. a night period of 6 h, and a 3-h period in the morning. The highest reflux frequency and the longest duration of oesophageal acid exposure were found in the postprandial hours (p < 0.001). Thereafter. all groups had an even reduction in reflux rate. A greater absolute reduction in the duration of oesophageal acid exposure could he measured in patients with pathologic reflux as compared with the other groups (p < 0.001). In spite of this, both reflux frequency and time with acid in the oesophagus were increased during the night in patients with pathologic reflux (p < 0.00l). Pathologic refluxers had in total 11 times as much reflux as normal subjects. and in addition 37.9% of the reflux took place during the 6 night hours. In contrast. only 5.4% of the reflux recorded in normal subjects occurred during this period. The pressure activity during periods with a normal intraoesophageal pH was reduced in all three groups during the night (p < 0.001). This reduction was more pronounced in normal suhjects than in duodenal ulcer patients (p < 0.02). resulting in a significantly higher pressure activity during the night in patients with duodenal ulcer (p < 01). Thesc data suggest that, with increasing acid reflux. a disproportionally greater part of this reflux takes place during the night. when the oesophagus is left most unprotected by peristalsis.

Key Words:

• Gastro-oesophageal reflux
• nighttime reflux
• non-pathologic refluxers
• oesophagus
• pathologic refluxers
• postprandial reflux
• pressurc activity