There are multiple causes of
GERD which may be different for different individuals or may be present in the same individual at different times.
Lower Esophageal Stricture Abnormalities (LES): LES is a very important ring-like muscular structure of the food pipe that prevents the backflow of stomach contents. It is present at the junction where the esophagus enters the stomach. The LES can contribute as one of the causes of GERD either if it is not contracting as strongly as it should or if it is relaxing more than it should.
Hiatal Hernia: Normally, LES is located at the level of the diaphragm (a muscular partition separating the chest and the abdomen). This diaphragm also helps LES to prevent reflux. However, in a hiatal hernia, a small portion of esophagus and the stomach is pushed upwards into the chest and the function of LES is compromised, playing a part in the causes of GERD.
Abnormal Esophageal Contractions: Usually when we swallow a morsel of food, the esophagus generates a successive series of contractions, in the form of waves, which help to push the food into the stomach. But, in some cases, the esophagus fails to contract effectively and food gets accumulated.
Slow or delayed emptying of the Stomach: Normally, it takes 1-3 hours for the stomach to empty its contents in the intestines. 70% of the food consumed can be digested in 3 hours. In certain cases prolonged or delayed emptying of stomach may cause stomach distension and thus transient LES relaxations.
In some individuals, the stomach on its own produces more acid than required, thus contributing as one of the causes of GERD.
Certain medications may also figure in the causes of GERD because of their side effects. These include
Beta-blockers, commonly used to treat high blood pressure
Calcium channel blockers, also prescribed for high blood pressure
Bronchodilators, used in management of Asthma
Tricyclic anti-depressants, frequently prescribed drugs for Depression
Dopamine-active drugs, given in cases of parkinsonism
