Gastroesophageal reflux with drifting onset in infants: a phenomenon unique to sleep

We have characterized the gastroesophageal reflux (GER) episodes which occurred during sleep in 28 infants with pathologic gastroesophageal reflux and 10 symptomatic age-matched controls without gastroesophageal reflux. We describe three kinds of episodes during the sleeping period-awake episodes which occur completely during electroencephalogram (EEG)-defined wakefulness associated with clinical evidence of the waking state (62 episodes), episodes occurring during EEG-defined sleep which have a rapid drop in pH at their onset (119 episodes), and episodes occurring during EEG-defined sleep in which the esophageal pH drifts down slowly over a period up to 30 min (113 episodes). Only 9 of the 10 control subjects experienced any reflux episodes during monitoring. The total number of episodes of reflux in controls (34) was less than the total number in reflux subjects (260). Controls did, however, experience all three types of reflux episode. Awake episodes all had a rapid drop in pH at their onset and were characterized by a short acid clearance time (2.0 +/- 0.3 min in reflux patients and 1.0 +/- 0.2 min in controls). The sleep episodes with rapid onset had longer mean acid clearance time than the awake episodes, significantly so in GER subjects (20.1 +/- 6.8 min in reflux subjects and 2.6 + 1.3 min in controls). Body movement was noted at the onset of 93.4% of rapid-onset sleep episodes in reflux subjects and 88.9% in controls. Body movement was also common at the termination of rapid-onset sleep episodes (77.8% of rapid-onset episodes in reflux subjects and 80.0% in controls).(ABSTRACT TRUNCATED AT 250 WORDS)