A hiatus hernia is a type of hernia in which abdominal organs (typically the stomach) slip through the diaphragm into the middle compartment of the chest. This may result in gastroesophageal reflux disease (GERD) or laryngopharyngeal reflux (LPR) with symptoms such as a taste of acid in the back of the mouth or heartburn. Other symptoms may include trouble swallowing and chest pains. Complications may include iron deficiency anemia, volvulus, or bowel obstruction. The most common risk factors are obesity and older age. Other risk factors include major trauma, scoliosis, and certain types of surgery.There are two main types: a sliding hernia, in which the body of the stomach moves up, and a paraesophageal hernia, in which an abdominal organ moves beside the esophagus. The diagnosis may be confirmed with endoscopy or medical imaging. Endoscopy is typically only required when concerning symptoms are present, symptoms are resistant to treatment, or the person is over 50 years of age.