Nocturnal Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a chronic disorder and the most common disease that affects the esophagus. A population-based study estimated that 20% of the U.S. adult population experiences GERDrelated symptoms at least once a week [1]. GERD can lead to esophageal mucosal injury in a subset of patients as well as bothersome symptoms, such as heartburn and acid regurgitation, which may affect patients’ quality of life. The epidemiology of nocturnal gastroesophageal reflux has only recently been examined. According to a Gallup poll from 1988 in which 1000 GERD patients completed a survey, 79% of the respondents reported nocturnal heartburn [2]. In a study by Farup et al, 74% of GERD patients with frequent GERD symptoms reported nocturnal GERD symptoms [3]. In contrast, Locke et al found in a community-based survey that 47% and 34% of the GERD sufferers reported nocturnal heartburn and nocturnal acid regurgitation, respectively [1]. Fass et al in a large prospective cohort study of subjects evaluated for sleep disturbances demonstrated that 24.9% reported heartburn during sleep [4]. Acid reflux episodes are divided into daytime reflux and nighttime reflux. However, because there is no clear definition of nighttime reflux, some prefer to divide episodes into reflux during the awake period and reflux during the sleep period. The latter division underscores the impact of sleep physiology on gastroesophageal reflux. Acid reflux during awake time tends to be more frequent but of shorter duration. In contrast, acid reflux during sleep is generally less frequent but of a significantly longer duration [5]. Nocturnal gastroesophageal reflux has been demonstrated to be an important underlying mechanism for the development of complicated GERD and extraesophageal manifestations of GERD. The latter may include oropharyngeal, laryngeal, and pulmonary manifestations [6,7]. The former may include erosive esophagitis, peptic stricture, esophageal ulcerations, Barrett’s esophagus, and adenocarcinoma of the esophagus. Furthermore, recent reports have demonstrated that nocturnal GERD is associated with poor quality of sleep and a variety of sleep disturbances [8,9]. Nocturnal reflux is also associated with reduced healthrelated quality of life as compared with the general population. In addition, patients with nighttime symptoms of GERD have a substantially diminished quality of life as compared with individuals without GERD symptoms during nighttime [3].