The nonerosive reflux disease-gastroesophageal reflux disease controversy.

PURPOSE OF REVIEW: To analyse the concept of nonerosive reflux disease (NERD), examining its evolving definition and its relationship to reflux disease and functional gastrointestinal disorders.

RECENT FINDINGS: The advent of the Montreal definition of gastroesophageal reflux disease (GERD) and the Rome III definition of functional upper gastrointestinal disorders has refined the concept of NERD. The high prevalence of GERD symptoms and the strong overlap between GERD and irritable bowel syndrome is due to the influence of NERD. Subtle differences exist between patterns of acid exposure in NERD and erosive disease on pH testing. Symptom generation in NERD may be influenced by altered mucosal permeability. Improvements in endoscopic technology demonstrate esophageal mucosal changes in NERD which are not seen in controls. There is a general acknowledgement that the inferior symptomatic response to acid suppression reported in NERD is attributable, at least in part, to contamination of study populations by patients with functional heartburn.

SUMMARY: NERD is common and its definition continues to evolve. For the present, however, this should be considered to be heartburn with and without regurgitation due to gastroesophageal reflux in the absence of esophageal mucosal erosions. Future studies examining treatment response of GERD subgroups must exclude functional heartburn if NERD is to be properly understood.