13 Sleep may alter physiological mechanisms responsible for normal esophageal clearance, resulting in increased esophageal acid exposure. Rate of swallowing

is reduced during sleep leading to decrease in primary peristalsis, a pivotal defense mechanism that is responsible for volume clearance of a refluxate from the esophagus.14,15 The latter results in decrease in acid clearance and thus increase in acid mucosal contact time.16 Diminished salivary production during sleep as well as reduced delivery of saliva to the distal esophagus due to decreased primary peristalsis delays alkalization and thus normalization of esophageal pH after acid reflux has occurred. The upper esophageal sphincter basal pressure, but not the lower esophageal sphincter, progressively declines with deeper sleep stages, resulting in an increased risk for aspiration in GERD patients. selleck chemicals Moreover, there is less conscious awareness of gastroesophageal reflux during sleep, resulting in reduction in symptom perception and thus alteration in conscious-dependent defensive

Erastin manufacturer behavior against gastroesophageal reflux (e.g. antacid consumption, assuming the upright position, initiating a swallow).17 Early studies have suggested that acid reflux was significantly more frequent during the first half of the supine period as compared with the second half.18 Dickman et al. demonstrated that esophageal acid exposure was the highest during the first 2 h of sleep.19 This was further triclocarban accentuated in patients with Barrett’s esophagus as compared to those with erosive esophagitis or non-erosive reflux disease with abnormal pH test. Patients with Barrett’s esophagus had the highest esophageal acid exposure parameters throughout the sleep period. Surprisingly, there was no difference in esophageal acid exposure parameters between patients with erosive esophagitis and those with non-erosive reflux disease and abnormal pH test. The increase in esophageal acid exposure during the first hours

of sleep is likely to be driven amongst others by short dinner-to-bed time. It has been shown that dinner-to-bed time less than 3 h significantly increased the risk of subjects to experience gastroesophageal reflux regardless of their phenotypic presentation of GERD (erosive esophagitis or non-erosive reflux disease).20 A recent article by Piesman et al. demonstrated that a meal consumed 2 h before going to bed was significantly more associated with supine reflux as compared to a meal consumed 6 h prior to bedtime.21 The presence of hiatal hernia, higher body mass index, and having erosive esophagitis increased the likelihood of developing supine reflux. Other factors like alcohol and/or carbonated beverage consumption, use of benzodiazepines at bedtime have all been shown to increase the risk for reported heartburn during sleep time.11,22 Dickman et al.