GERD and its complications. The pathogenic relationship between symptoms and disease progression.

Chronic daytime and noctural acid reflux causes mucosal damage, heartburn, and other symptoms of GERD. The esophageal complications of GERD result from long-term exposure of the esophagus to acid. Extraesophageal GERD complications, such as laryngitis and asthma, develop when some of the acidic refluxate in the proximal esophagus enters the lower or upper airways because of comprised defense mechanisms. A growing body of evidence suggests that nocturnal reflux is more important to the development of severe complications than is daytime reflux. Defects in the lower esophageal sphincter and clearance mechanisms are related in part to recumbency during sleep; they may explain why transient episodes of nocturnal reflux outnumber daytime episodes in patients with GERD. Currently, the hope is that management strategies aimed at control of nocturnal symptoms can prevent, reduce the severity of, or resolve the long-term complications of chronic GERD.