Gastroesophageal Reflux Disease - Causes

Causes

GERD is caused by a failure of the cardia. In healthy patients, the "Angle of His"—the angle at which the esophagus enters the stomach—creates a valve that prevents duodenal bile, enzymes, and stomach acid from traveling back into the esophagus where they can cause burning and inflammation of sensitive esophageal tissue.

Factors that can contribute to GERD:

• Hiatal hernia, which increases the likelihood of GERD due to mechanical and motility factors.
• Obesity: increasing body mass index is associated with more severe GERD. In a large series of 2000 patients with symptomatic reflux disease, it has been shown that 13% of changes in esophageal acid exposure is attributable to changes in body mass index.
• Zollinger-Ellison syndrome, which can be present with increased gastric acidity due to gastrin production.
• Hypercalcemia, which can increase gastrin production, leading to increased acidity.
• Scleroderma and systemic sclerosis, which can feature esophageal dysmotility.
• The use of medicines such as prednisolone.
• Visceroptosis or Glénard syndrome, in which the stomach has sunk in the abdomen upsetting the motility and acid secretion of the stomach.

GERD has been linked to a variety of respiratory and laryngeal complaints such as laryngitis, chronic cough, pulmonary fibrosis, earache, and asthma, even when not clinically apparent. These atypical manifestations of GERD is commonly referred to as laryngopharyngeal reflux or as extraesophageal reflux disease (EERD).

Factors that have been linked with GERD, but not conclusively:

• Obstructive sleep apnea
• Gallstones, which can impede the flow of bile into the Duodenum, which can affect the ability to neutralize gastric acid

In 1999, a review of existing studies found that, on average, 40% of GERD patients also had H. pylori infection. The eradication of H. pylori can lead to an increase in acid secretion, leading to the question of whether H. pylori-infected GERD patients are any different than non-infected GERD patients. A double-blind study, reported in 2004, found no clinically significant difference between these two types of patients with regard to the subjective or objective measures of disease severity.