Gastro-oesophageal reflux and the migrating motor complex

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 < 0.001) and more frequent (p < 0.005) than during periods of gastric motor quiescence. At night, periodic gastric motor activity was thus correlated (p < 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 < 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.