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

The aim of the investigation was to evaluate the relative quantity of acid gastrooesophageal reflux during different time periods in subjects with and without pathologic reflux. Twenty duodenal ulcer patients, 10 with and 10 without pathologic acid gastro-oesophageal reflux, and 26 asymptomatic volunteers were subjected 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 less than 0.001). Thereafter, all groups had an even reduction in reflux rate. A greater absolute reduction in the duration of oesophageal acid exposure could be measured in patients with pathologic reflux as compared with the other groups (p less than 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 less than 0.001). 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 less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)