Basal lower esophageal sphincter pressure in gastroesophageal reflux disease: An ignored metric in high-resolution esophageal manometry.

Abstract

Manometry and 24-h pH interpretation have seldom been studied. Our aim was to study these parameters as gold standard in reflux disease and to identify predictors of pathological acid reflux. Retrospective case record review of all patients with reflux disease evaluated using endoscopy, manometry, and 24-h pH testing from 2010 to 2016. Patients were categorized using Johnson-DeMeester score into two groups-group I (score > 14.7, normal study) and group II (< 14.7, normal study). These groups were compared for the above-mentioned parameters. Appropriate statistical tests were applied. P-value < 0.05 was considered significant. The study group includes 94 patients (median age 44 years, 63.8% males). Sixty (63.8%) and 34 patients belonged to groups I and II, respectively, 76.6% patients had normal endoscopy while the remaining had mild esophagitis. Peristalsis was normal in 66%, followed by ineffective esophageal motility (19.1%) and fragmented peristalsis (14.9%). Demography, symptoms, endoscopy findings, and peristalsis characteristics were similar between the two groups. Group II patients had significantly lower basal lower esophageal sphincter (LES) pressure (11.9 vs. 16.6; p < 0.02), lower integrated relaxation pressure (5.7 vs. 7.4; p < 0.01), and larger separation between LES and crural diaphragm (1.7 vs. 1.4 cm; p < 0.003). Basal LES pressure < 10 mmHg had the highest likelihood ratio (2.2) to predict an abnormal pH study. Basal LES pressure, integrated relaxation pressure, and hiatus size correlated with pathological acid reflux. Hypotensive basal lower esophageal sphincter pressure was the best predictor of an abnormal pH study but with negative linear correlation.