title: Non-erosive reflux disease (NERD)--acid reflux and symptom patterns.
abstract: BACKGROUND
  Recent reports suggest that patients with non-erosive reflux disease (NERD) treated with anti-reflux medications show lower symptom improvement rates than patients with erosive oesophagitis treated with the same medications.
  
  
  OBJECTIVE
  To determine the acid reflux and symptom patterns of patients with NERD in comparison with those with erosive oesophagitis and Barrett's oesophagus, and to identify different NERD subgroups.
  
  
  METHODS
  One hundred and forty-nine consecutive patients seen for classic heartburn symptoms were evaluated for the study. Oesophageal mucosal injury was assessed by upper endoscopy and classified by Hetzel-Dent criteria. Patients with Hetzel-Dent grades 0-1 were considered to have NERD. The extent of oesophageal acid exposure was determined by ambulatory 24-h oesophageal pH monitoring.
  
  
  RESULTS
  Seventy-one patients were found to have NERD, 36 erosive oesophagitis and 42 Barrett's oesophagus. Compared with patients with erosive oesophagitis (75%) and Barrett's oesophagus (93%), those with NERD (45%) were significantly less likely to have an abnormal pH test (P = 0.0001). Patients with Barrett's oesophagus had the highest mean number of acid reflux events (210 +/- 17.7), compared with those with erosive oesophagitis (139.7 +/- 15.2) and NERD (95.3 +/- 9.4) (P = 0.0001); however, the rate of perceived acid reflux events was similar and very low in all groups (NERD, 3.6%; erosive oesophagitis, 2.9%; Barrett's oesophagus, 2.17%). NERD-positive patients (abnormal pH test) had a similar extent of oesophageal acid exposure to those with erosive oesophagitis. NERD-positive patients were more likely to demonstrate a symptom index greater than 75% than NERD-negative patients (normal pH test) (61.9% vs. 10.5%; P = 0.0001). In the NERD-negative group, those with a negative symptom index reported having heartburn at pH < 4 only 12.7% of the time, compared with 70.7% of the time in those with a positive symptom index, despite a similar mean number of heartburn episodes.
  
  
  CONCLUSIONS
  Patients with NERD commonly demonstrate a negative pH test. Acid reflux characteristics and symptom patterns suggest a heterogeneous group of patients.
authors.affiliation: Department of Medicine, Section of Gastroenterology and Hematology/Oncology, Southern Arizona VA Health Care System and Arizona Health Sciences Center, Tucson, AZ 85723, USA.
authors.forename: S D
authors.initials: SD
authors.lastname: Martinez
authors.forename: I B
authors.initials: IB
authors.lastname: Malagon
authors.forename: H S
authors.initials: HS
authors.lastname: Garewal
authors.forename: H
authors.initials: H
authors.lastname: Cui
authors.forename: R
authors.initials: R
authors.lastname: Fass
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care; D001471:Barrett Esophagus / Q000175:diagnosis; D004942:Esophagitis, Peptic / Q000175:diagnosis; D004945:Esophagoscopy; D005260:Female; D005744:Gastric Acid; D005764:Gastroesophageal Reflux / Q000175:diagnosis*; D006356:Heartburn / Q000209:etiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged