BACKGROUND: Gastroesophageal reflux disease is a very frequent clinical condition and nocturnal symptoms are a cause of quality of life impairment, poor sleep quality and absenteeism. Head of bed elevation, as a low-cost non pharmacologic anti-reflux treatment is nowadays recommended, but its clinical impact in patients with nocturnal symptoms remains unknown due to inconsistent results and methodological limitations among different clinical trials, most of which were performed before the widespread use of proton pump inhibitors in clinical practice.