Gastroesophageal reflux disease is the reflux of gastroduodenal contents into the esophagus causing heartburn and other symptoms, and can cause reflux esophagitis, as well as damage to tissues adjacent to the esophagus such as the pharynx and airway. Epidemiology of gastroesophageal reflux disease Gastroesophageal reflux disease is very common in Western countries, about 7%-15% of the population has gastroesophageal reflux symptoms, the incidence increases with age, 40-60 years old is the peak incidence age, there is no difference in the incidence of men and women, but in reflux esophagitis, more men than women (2-3:1). The prevalence of GERD in Beijing and Shanghai is 5.77%, and that of GERD is 1.92%, which is lower than that in western countries, and the disease is also milder. Clinical manifestations of GERD 1. Heartburn and acid reflux: Heartburn is a burning sensation behind the sternum and under the glabella, mostly occurs one hour after meals, and is likely to occur when lying down, bending over or when the abdominal pressure is increased. 2. Painful swallowing and dysphagia: Painful swallowing can occur when there is severe esophagitis or esophageal ulcer, which is caused by acidic reflux stimulating the sensory nerve endings under the epithelium of the esophagus. Reflux can also stimulate mechanoreceptors to cause spasmodic esophageal pain, which can be severe stabbing pain radiating to the back, waist, shoulders and neck, similar to angina pectoris. Due to esophageal spasm or dysfunction, some patients may have difficulty swallowing, and when esophageal stricture occurs, the difficulty in swallowing continues to worsen. 3, other: regurgitant stimulation of the pharyngeal mucosa can cause pharyngitis, hoarseness, pharyngeal discomfort or foreign body sensation. Inhalation of the respiratory tract can occur cough, asthma, this asthma is not seasonal, often at night paroxysmal cough and shortness of breath. Individual patients have recurrent aspiration pneumonia and even interstitial lung fibrosis.