Gastroesophageal Reflux Disease (GERD) is a chronic condition where stomach acid flows back up into the esophagus, the tube connecting the mouth and stomach. While occasional acid reflux is common, GERD involves frequent and persistent backflow that exposes the delicate esophageal lining to corrosive stomach contents. When GERD is not managed, this continuous chemical assault leads to a progressive sequence of tissue damage. Ignoring this chronic irritation allows inflammation to worsen, setting the stage for structural changes and increasing the risk of serious long-term health complications both within and outside the esophagus.
Esophagitis and Ulcerations
The first direct consequence of chronic, untreated acid exposure is inflammation of the esophageal lining, known as esophagitis. The protective squamous cells of the esophagus are not built to withstand the highly acidic environment of the stomach. Constant contact with refluxed acid and digestive enzymes causes the tissue to become irritated and swollen, often resulting in burning chest discomfort and pain.
If acid exposure continues unchecked, inflammation progresses, leading to erosions and ultimately, painful esophageal ulcers. These ulcers are open sores where the tissue has been worn away. Ulcers can cause severe pain when swallowing (odynophagia) and may result in gastrointestinal bleeding. Chronic blood loss from these damaged areas can lead to iron-deficiency anemia.
Development of Esophageal Strictures
The body’s natural response to persistent injury and ulceration is to initiate healing through scar tissue formation. Chronic inflammation from untreated GERD stimulates cells to secrete collagen, which is intended to repair deep tissue defects left by ulcers. However, this repeated cycle of damage and repair causes the esophageal wall to become stiff and scarred.
This excessive scar tissue eventually contracts, leading to a narrowing of the esophageal tube, known as an esophageal stricture. Strictures impede the passage of food, causing progressive difficulty swallowing solid foods (dysphagia). As the stricture worsens, a person may struggle to swallow even soft foods or liquids, potentially leading to unintentional weight loss and malnutrition. Treating strictures often requires endoscopic dilation to physically stretch the narrowed area.
Barrett’s Esophagus and Increased Cancer Risk
A concerning pathological change arising from long-standing GERD is Barrett’s Esophagus (BE). This condition involves a metaplastic change where the normal squamous cells of the lower esophagus are replaced by columnar cells, which typically line the intestine. This cellular transformation is thought to be an adaptive mechanism against continuous acid and bile exposure. While only a minority of people with GERD develop BE, it is a significant long-term risk of non-treatment.
Barrett’s Esophagus is the only known precursor to esophageal adenocarcinoma (EAC), a serious form of cancer. The cells in BE can become increasingly abnormal, progressing through stages known as low-grade dysplasia and high-grade dysplasia, before becoming invasive cancer. Although the annual risk of progression from BE to EAC is small (around 0.3% per year), the presence of BE mandates regular endoscopic surveillance. This allows doctors to monitor cellular changes and treat precancerous lesions.
Extra-Esophageal Complications
Untreated GERD can cause complications outside the esophagus. These extra-esophageal manifestations occur when refluxed acid travels past the upper esophageal sphincter and reaches the throat and airways. One common consequence is chronic cough, caused by acid irritating the vocal cords or by a neural reflex triggered by acid contact in the esophagus.
Reflux reaching the throat can cause laryngitis, resulting in persistent hoarseness and a sensation of a lump in the throat. Individuals with pre-existing asthma may experience more frequent and severe asthma attacks due to acid micro-aspiration or a vagus nerve-mediated reflex causing airway constriction. Furthermore, acidic content can erode the enamel on the back surfaces of teeth, leading to dental problems. Proper diagnosis and treatment of the underlying reflux condition is necessary for resolving these seemingly unrelated respiratory and oral health issues.