Gastroesophageal Reflux Disease

SOURCE

Source: May D, Thiman M, Rao SCS. Gastroesophageal reflux disease. In: DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM, eds. Pharmacotherapy: A Pathophysiologic Approach. 10th ed. New York, NY: McGraw-Hill; 2017. http://accesspharmacy.mhmedical.com/content.aspx?bookid=1861&sectionid=135145538. Accessed March 27, 2017.

CONDITION/DISORDER SYNONYMS

• Heartburn.

• Acid reflux disease.

• GERD

DEFINITION

• Retrograde movement of stomach contents into esophagus causing troublesome symptoms and/or complications.

ETIOLOGY

• Defective lower esophageal sphincter (LES) pressure or function.

• Abnormal esophageal anatomy.

• Improper esophageal clearance of gastric fluids.

• Reduced mucosal resistance to acid.

• Delayed or ineffective gastric emptying.

• Reduced salivary buffering of acid.

PATHOPHYSIOLOGY

• Decreased LES pressure may result from spontaneous transient LES relaxations, transient increases in intraabdominal pressure, atonic LES, or ingestion of certain foods and medications.

• Substances that promote esophageal damage upon reflux include gastric acid, pepsin, bile acids, and pancreatic enzymes.

• Composition and volume of refluxate and duration of exposure are most important factors in determining clinical consequences.

• Complications from long-term acid exposure include esophagitis, esophageal strictures, Barrett esophagus, and esophageal adenocarcinoma.

EPIDEMIOLOGY

• Most common in persons older than 40 years.

• 20% of adults in Western countries suffer from GERD symptoms on weekly basis.

• Prevalence of GERD highest in Western countries.

• No difference in incidence between men and women, except for higher incidence during pregnancy.

RISK FACTORS

• Obesity.

• Smoking.

• Alcohol consumption.

• Certain medications and foods.

CLINICAL PRESENTATION

SIGNS AND SYMPTOMS

• Heartburn (substernal sensation of warmth or burning rising up from abdomen that may radiate to neck), water brash (hypersalivation), belching, regurgitation.

• Pain may wax and wane and be aggravated by activities that worsen reflux (eg, recumbent position, bending over, or high-fat meals).

• Extraesophageal symptoms may include chronic cough, laryngitis, asthma, and dental enamel erosion.

• Alarm symptoms include dysphagia, odynophagia, and unexplained weight loss.

• Tissue injury-based GERD (with or without symptoms) may present with esophagitis, esophageal strictures, Barrett esophagus, or esophageal carcinoma.

DIAGNOSIS

MEANS OF CONFIRMATION AND DIAGNOSIS

• Clinical history, including symptoms and risk factors.

• Patients with mild, typical symptoms do not usually require invasive evaluation.

• Clinical diagnosis can be assumed in patients who respond to appropriate therapy.

• Perform diagnostic tests in patients who do not respond to therapy or who present with alarm symptoms.

IMAGING

• Barium radiography not routinely used—lacks sensitivity and specificity, and cannot identify Barrett esophagus.

DIAGNOSTIC PROCEDURES

• Endoscopy preferred for assessing mucosa for esophagitis, identifying Barrett esophagus, and diagnosing complications.

• Camera-containing capsule swallowed by patient can visualize esophageal mucosa.

• Ambulatory pH monitoring helps correlate symptoms with abnormal esophageal acid exposure.

• Combined impedance–pH monitoring measures both acid ...