Epidemiology of esophageal and supraesophageal reflux injuries.

Gastroesophageal reflux disease (GERD) is a common gastrointestinal disorder. Despite its frequent occurrence, only a minority of patients seek medical attention, making it difficult to ascertain the true epidemiologic distribution of the disorder. A causal association between GERD and esophageal complications such as esophagitis, esophageal ulcer, and esophageal stricture is well accepted. Recent epidemiologic evidence suggests that GERD may likewise represent a risk factor for the development of supraesophageal conditions, such as asthma, chronic bronchitis, laryngitis, and even laryngeal cancer. Although epidemiologic associations do not establish a cause-and-effect relationship, they may indicate potential etiologic risk factors. Nevertheless, confirmation of the causal role of GERD in supraesophageal disorders awaits further investigation.