title: Symptom severity and oesophageal chemosensitivity to acid in older and young patients with gastro-oesophageal reflux.
abstract: BACKGROUND
  elderly patients appear to have a more aggressive form of gastro-oesophageal reflux disease than younger patients. Reduced pain perception with age is a possible underlying mechanism.
  
  
  OBJECTIVE
  to compare the extent of oesophageal mucosal injury, acid exposure, symptom severity and perception thresholds for acid infusion in older (aged 60 or older) and younger patients with gastro-oesophageal reflux.
  
  
  METHODS
  twenty-five younger and 23 older patients completed the study. We determined acid exposure and oesophageal mucosal injury by ambulatory 24-h oesophageal pH monitoring and upper endoscopy, respectively. We determined chemosensitivity by infusing 0.1 N hydrochloric acid into the mid-oesophagus for 10 min at 10 ml/min after a 2-min infusion of normal saline at a similar rate. We quantified acid perception thresholds by the lag time to initial typical symptom perception, intensity rating at the end of acid infusion and an acid perfusion sensitivity score, calculated from the fractional duration of symptom perception and intensity rating.
  
  
  RESULTS
  mean percentage of total time with pH <4 was higher in the older (15.8+/-2.4) than in the younger patients (11.9+/-1.8; P = 0.18). Of the older group, 74% had erosive oesophagitis versus 64% in the younger group. Frequency of symptoms (heartburn, acid regurgitation and dysphagia) was lower in the elderly group. Older patients perceived heartburn and acid regurgitation as much less severe than younger patients (P < 0.05).Younger patients had a significantly shorter lag time to initial symptom perception (P < 0.05) and a higher sensory intensity rating (P < 0.08). The acid perfusion sensitivity score was significantly lower in the older group (P < 0.05).
  
  
  CONCLUSIONS
  older patients with gastro-oesophageal reflux disease have reduced symptom severity for heartburn despite a tendency towards increased severity of oesophageal mucosal injury and acid exposure. Age-related reduction in chemosensitivity to acid is a possible underlying mechanism.
authors.affiliation: Section of Gastroenterology, Department of Medicine, Tucson VA Medical Center and Arizona Health Sciences Center, 85723, USA. Ronnie.Fass@Med.VA.gov
authors.forename: R
authors.initials: R
authors.lastname: Fass
authors.forename: G
authors.initials: G
authors.lastname: Pulliam
authors.forename: C
authors.initials: C
authors.lastname: Johnson
authors.forename: H S
authors.initials: HS
authors.lastname: Garewal
authors.forename: R E
authors.initials: RE
authors.lastname: Sampliner
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D004947:Esophagus / Q000187:drug effects*; D005260:Female; D005764:Gastroesophageal Reflux / Q000503:physiopathology*; D006801:Humans; D006851:Hydrochloric Acid / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged
chemical_list: D006851:Hydrochloric Acid