A syndrome due to structural or functional incompetence of the lower esophageal sphincter (LES), which permits retrograde flow of acidic gastric juice into the esophagus.
Although the underlying abnormality in GERD is apparently inborn and irreversible, the incidence of symptomatic disease increases with age. In addition to reflux, most cases involve disordered gastric motility and delayed gastric emptying. Symptoms include recurring epigastric and retrosternal distress, usually described as heartburn, along with varying degrees of belching, nausea, gagging, cough, or hoarseness. Almost 50% of adults in the U.S. report experiencing these symptoms at least once a month, and almost 20% experience them at least once a week. GERD is increasingly recognized as a cause of throat irritation and chronic cough. The incidence of GERD among adults with asthma may be as high as 80%. The disorder is more common in men. The likelihood of symptomatic reflux is increased by obesity, pregnancy, cigarette smoking, diabetes mellitus, scleroderma, and other connective tissue diseases. Symptoms can be induced by recumbency, strenuous exercise, heavy lifting, smoking, eating large meals, or consuming alcohol, chocolate, fatty foods, and drugs such as theophylline, calcium channel blockers, and anticholinergic agents. Acid reflux can cause peptic esophagitis, ulcer formation, esophageal stricture, or metaplastic change in esophageal squamous epithelium, called Barrett esophagus, which can progress to carcinoma. Diagnosis of GERD is by history, esophageal pH monitoring, radiologic study showing reflux of swallowed barium, and endoscopy to identify ulceration or stricture and permit biopsy to rule out malignancy. Treatment includes avoidance of known aggravating factors and administration of antacids, H2 antagonists, prokinetic agents, and proton pump inhibitors. Surgical procedures to inhibit reflux mechanically, particularly Nissen fundoplication, can improve symptoms in severe disease but have not been shown to prevent carcinoma in patients with GERD and Barrett esophagus. Fewer than one half of patients who have had surgery remain symptom free without antisecretory medicine. Gastroesophageal reflux, with passive regurgitation of feedings, occurs in about 50% of healthy infants but seldom persists beyond 1 year of age.
Reference: Stedman's Medical Dictionary