What is acid reflux (GERD)?


Gastroesophageal reflux disease (GERD), also known as acid reflux is a long-term condition where contents of the stomach regurgitate or travel backwards into the oesophagus, resulting in symptoms or complications. The likelihood of developing GERD increases when there are more acid and food content in the stomach.

Approximately half of American adults have heartburn or regurgitation at least once monthly, and 5% – 10% struggle with reflux symptoms every day. According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), around 20% of the population in the United States has GERD in 2015.  Healthcare Cost and Utilisation Project study reveals that hospitalisations in the US due to GERD increased by 216% between 1998 and 2005.

of Americans suffer from heartburn or acid reflux once monthly
of Americans struggle with reflux symptoms daily
of the Americans has GERD in 2015

Unlike the stomach and duodenum, the oesophagus does not have a protective lining to prevent gastric acid from eroding the underlying tissue. Constant backwash of gastric acid can irritate and wear off the oesophageal lining, leading to inflammation (oesophagitis). Over time, complications such as bleeding, oesophageal narrowing or Barrett’s esophagus can result.

i) Bleeding:

Excessive bleeding from the oesophageal lining causes blood to flow into the digestive tract and later eliminated from the body as dark, tarry stools. In addition, oesophagitis can also cause ulcers which are open sores on the lining of the oesophagus.

ii) Oesophageal narrowing:

Repeated injury and healing of inflammation (oesophagitis) can chronically scar the oesphagus. The scar tissue, a benign stricture that developed as a concentric ring narrows the opening of the oesphagus, often at the junction between the oesophagus and stomach. Oesophageal narrowing may result in swallowing difficulty (dysphagia) and interference to food and liquids passing into the stomach. It can also cause oesophageal spasms and severe chest pains that mimic a heart attack. Oesophageal narrowing can be rectified by passing a dilator through the narrowed area to break the scar tissue.

Oesophageal narrowing

iii) Barrett’s oesophagus:

Barrett’s oesophagus occurs in around 10% to 15% of people with long-standing history of GERD. Barrett’s oesophagus develops when the normal tissue lining the oesophagus is damaged by acid reflux and replaced by tissue that resembles the intestinal lining. This increases the risk of oesophageal cancer. Routine endoscopies with oesophagus biopsies are necessary for individuals with Barrett’s oesophagus, to check for dysplasia, an enlargement of a tissue of abnormal cell type, as an early stage in cancer development.

Normal lower oesophagus

Barrett’s oesophagus

Barrett’s oesophagus

Barrett’s oesophagus

Video on GERD and its adverse effects to the body