Abstract

Distal oesophageal pH and gastroduodenal motor activity were recorded simultaneously throughout nocturnal (23 30-08 30 h) and diurnal (08 30-17 30 h) periods of fasting in seven healthy subjects. At night, episodes of gastro-oesophageal reflux (GOR) accounted for 1.2 +/- 0.7% of recording time. Periods of gastric motor activity, representing the gastric component of the migrating motor complex (MMC), recurred every 78 +/- 31 min during the night and were interspersed with periods of gastric motor quiescence. Nocturnal episodes of GOR during periods of gastric motor activity were of longer duration (p less than 0.001) and more frequent (p less than 0.005) than during periods of gastric motor quiescence. At night, periodic gastric motor activity was thus correlated (p less than 0.001) with an increase in the duration and number of GOR episodes and associated with a 100-fold increase in oesophageal acid exposure. During the day, the gastric component of the MMC, recurring every 131 +/- 64 min, was correlated (p less than 0.02) with an increase in the duration and number of GOR episodes, and a three fold increase in oesophageal acid exposure. Further, 89% of nocturnal, and 83% of diurnal gastric MMCs were temporally associated with episodes of GOR. We conclude that fasting episodes of GOR occur coincidentally with the gastric component of the MMC.