Chronic gastroesophageal reflux disease (GERD) increases cancer risk in aging adults primarily because the persistent exposure of the esophageal lining to stomach acid causes ongoing inflammation and cellular damage. Over time, this chronic irritation can lead to changes in the cells of the esophagus, increasing the likelihood of developing precancerous conditions and eventually esophageal cancer.
When stomach acid repeatedly flows back into the esophagus, it damages the normal squamous cells lining the esophagus. The body responds to this damage by replacing these cells with a different type of cell more resistant to acid, known as columnar epithelium, in a process called Barrett’s esophagus. While this adaptation may protect the esophagus from acid, Barrett’s esophagus is a precancerous condition that significantly raises the risk of esophageal adenocarcinoma, a type of cancer that becomes more common with age.
Aging itself contributes to this increased cancer risk because the natural ability of cells to repair DNA damage declines, and the immune system becomes less efficient at identifying and destroying abnormal cells. Chronic inflammation from GERD creates a microenvironment rich in inflammatory molecules and oxidative stress, which can cause genetic mutations and promote abnormal cell growth. This environment also encourages cellular senescence, where cells stop dividing but secrete factors that promote tumor growth and tissue remodeling, further increasing cancer risk.
Moreover, the repeated injury and repair cycles in the esophageal lining can lead to genomic instability, where DNA damage accumulates and the normal controls on cell growth are lost. This instability is a hallmark of cancer development. The metabolic changes in these damaged cells, including shifts toward glycolysis even in the presence of oxygen (known as the Warburg effect), support rapid cell proliferation and survival of potentially malignant cells.
Other factors common in aging adults, such as obesity, smoking, and dietary habits, can exacerbate GERD symptoms and further increase the risk of progression to cancer. Obesity, for example, increases abdominal pressure, worsening reflux, and is independently associated with higher rates of esophageal and stomach cancers.
In addition to esophageal cancer, chronic GERD has been linked to other complications that may indirectly influence cancer risk. For instance, chronic inflammation and acid exposure can affect nearby tissues and organs, potentially contributing to other gastrointestinal malignancies.
In summary, chronic GERD increases cancer risk in aging adults through a combination of persistent acid-induced injury, cellular adaptation to acid exposure (Barrett’s esophagus), chronic inflammation, impaired DNA repair, and metabolic changes in esophageal cells. Aging amplifies these risks by weakening the body’s defenses against cellular damage and malignancy, making long-term management of GERD crucial to reduce cancer development.