Acid clearance during sleep in the pathogenesis of reflux esophagitis

Impaired esophageal clearing of refluxed gastric contents during sleep has been implicated in the pathogenesis of reflux esophagitis. To more directly evaluate this hypothesis, 13 symptomatic patients with esophagitis and 13 normal controls had 15 ml of 0.1 N HCl instilled into the esophagus in the recumbent position while awake and during polygraphically monitored sleep. When sleep was maintained for the majority of the acid-clearing duration, the clearance times for both patients and controls were significantly prolonged when compared to those while awake (P less than 0.01). However, when sleep was maintained for less than 50% of the acid-clearing interval, the patients showed significantly longer acid clearance times. The swallowing rate did not differentiate the two groups under any condition. These data show that sleep impairs esophageal acid clearance. Acid clearance occurred predominantly in association with arousals from sleep. The defective acid clearance found in patients with esophagitis probably plays a major role in the pathogenesis of this disorder.