Sa1184 A Comparison of Rectal and Esophageal Sensitivity in Women With Functional Heartburn

Abstract

Background: Functional Gastrointestinal Disorders (FGIDs) are identified by the dominant presenting symptoms: functional heartburn (FH), irritable bowel syndrome (IBS), dyspepsia, etc. This nomenclature assumes an organ-specific origin of symptoms rather than symptoms associated with a common pathophysiology such as visceral hypersensitivity. The symptoms reported in most FGIDs overlap more than one gastrointestinal (GI) organ. FH patients report abdominal cramping, bloating and nausea with their FH symptoms. This study tested the primary hypothesis that there is a correlation of MPT in the esophagus and rectum in FH patients. Secondary aims evaluated correlations with IPT and PT. Methods:. This study explored objective sensory endpoints of initial perception threshold (IPT), pain threshold (PT), and maximum pain threshold (MPT) in the esophagus and rectum of FH subjects to determine whether visceral hypersensitivity is a generalized or organ specific observation Fourteen women with FH participated in this study. Each subject underwent a training sensory study protocol session including step volume and pressure ramp balloon barostat distention of the esophagus and rectum. A data collection visit occurred within 7-14 days to collect data on balloon volume and pressure measurements at IPT, PT, and MPT with esophageal and rectal barostat distention. The relationship of sensation and pain to volume, pressure, and compliance was analyzed. Results: The correlation between esophageal and rectal IPT balloon volume scores was highly and significantly correlated (r = 0.61, p = 0.02). The correlation between esophageal and rectal PT balloon volume scores was highly and significantly correlated (r = 0.6, p = 0.02). The correlation between esophageal and rectal MPT balloon volume scores was not correlated (r = 0.35, p = 0.26). In contrast to volume, the pressure endpoints were not significantly correlated. Conclusions: 1. In this study, there was weak correlation for the relationship of rectal and esophageal volume scores at MPT (Primary Aim). Findings revealed a strong positive correlation for the relationship of rectal and esophageal volume and pressure scores to IPT and PT (Secondary Aims). The lack of MPT correlation may provide insight into the organ specific stratification of FGIDs through identification of the most sensitive organ. 2. In this study, volume was superior to pressure in assessing changes in visceral sensitivity in FGID patients. 3. The correlation of visceral sensitivity in the esophagus and rectum in patients with FH supports the hypothesis that visceral sensory changes in FGIDs are not organ specific. 4. Visceral hypersensitivity throughout the GI tract may explain the overlapping symptoms in FGID patients suggesting visceral sensitivity may occur in two separate areas of the GI tract simultaneously.