Upon completion of the chapter, the reader will be able to:
Explain the underlying causes of gastroesophageal reflux disease (GERD).
Understand the difference between typical, atypical, and alarm symptoms.
Determine when diagnostic tests should be recommended based on the clinical presentation.
Identify the desired therapeutic outcomes for patients with GERD.
Recommend appropriate nonpharmacologic and pharmacologic interventions for patients with GERD.
Educate patients on appropriate lifestyle modifications and drug therapy issues including adherence, adverse effects, and drug interactions.
Formulate a monitoring plan to assess the effectiveness and safety of pharmacotherapy for GERD.
Gastroesophageal reflux is the retrograde, effortless movement of stomach contents into the esophagus. When troublesome symptoms or mucosal damage occurs as a result of this process, this is defined as gastroesophageal reflux disease (GERD).1,2 Treatment is usually initiated based on symptom presentation rather than laboratory tests or invasive monitoring and consists of various lifestyle interventions and pharmacotherapy. Lack of response to empiric therapies may require further evaluation to identify potential underlying complicating conditions.1,3
EPIDEMIOLOGY AND ETIOLOGY
GERD is one of the most common gastrointestinal conditions. Up to 40% of Americans report intermittent GERD symptoms, with 10% to 20% of the US population reporting at least weekly symptoms.1 GERD symptoms can result in morbidity and decreased work productivity. The incidence of erosive esophagitis and Barrett esophagus increases with age, especially in Caucasian men over 50 years of age with symptoms for more than 10 years.3,4
The precise etiology of GERD is difficult to determine in most patients. Increased intraabdominal pressure or decreased lower esophageal sphincter (LES) tone may allow gastric refluxate to enter the esophagus causing GERD symptoms in some patients. These processes can be transient and are often due to physical activity, food, or medications.
Retrograde movement of gastric contents into the esophagus, oral cavity, or lungs is the origin of symptoms or complications that define GERD. Reflux is normally prevented through muscle tone of the LES. Reduction in LES function or tone may allow reflux of gastric contents into the esophagus. Other physiologic and mucosal defense mechanisms may also become compromised and affect the refluxate composition and development of GERD. Such mechanisms include slowed esophageal clearance, decreased salivary buffering, impaired mucosal resistance, delayed gastric emptying, and increased intraabdominal pressure.
Lower Esophageal Sphincter Pressure
In the normal state, the LES maintains a tonic pressure that separates gastric contents from the esophagus, relaxing during swallowing to allow esophageal contents to pass into the stomach. Decreased LES pressure can occur via spontaneous relaxation, increased intraabdominal pressure, and an atonic LES. Spontaneous relaxation of the LES occurs during vomiting, belching, retching, and esophageal distention. Transient increases in intraabdominal pressure may occur during straining, exercise, bending over, or Valsalva ...