Objective: The stomach contents become hypertonic after a meal and provide esophageal refluxate that is both acidic and hypertonic. This study examined the symptomatic response to esophageal exposure to hypertonic and acidic solutions in patients with gastroesophageal reflux disease (GERD) and Barrett's esophagus.
Methods: Symptom intensity and character were measured in double-blind fashion during esophageal instillation of water, hypertonic saline (osmolality 1030 mOsm/kg), hydrochloric acid (pH 1 and 2.5), and acidified hypertonic saline (pH 1 and 2.5). The studies were performed in healthy controls and GERD patients with and without Barrett's esophagus.
Results: The GERD patients with Barrett's differed from the non-Barrett's GERD patients in being less sensitive to acid (mean intensity score, 2.3 vs 4.8, p < 0.05), more sensitive to hypertonic saline (1.3 vs 0.4, p < 0.05) and by showing an additive effect when the acid and hypertonic solutions were combined, resulting in similar scores in the two patient groups to the combination (4.4 vs 4.3). The frequency of nausea was higher in the Barrett's group compared to the other GERD patients after hypertonic saline (21% vs 0%, p < 0.05), acid (50% vs 21%, p < 0.05) and the acid hypertonic combination (71% vs 29%, p < 0.05).
Conclusions: Barrett's mucosa is associated with reduced symptomatic response to acid, increased response to hypertonic solutions, and a higher incidence of nausea in response to either stimulus.