Supplement Abstracts Submitted for the 73rd Annual Scientific Meeting of the American College of Gastroenterology: ESOPHAGUS
Purpose: There is a known association between obesity and GERD, thought to be due to increased intragastric pressure and spatial separation between the lower esophageal sphincter and crural diaphragm. Our aim was to investigate the relationship between BMI, LES characteristics, and frequency of reflux episodes.
Methods: All patients undergoing both esophageal manometry and 24-hour impedance-pH reflux monitoring in 2007–2008 for whom BMI was available were included. We evaluated the association between BMI and the following variables: (a) Manometric lower esophageal sphincter (LES) characteristics: resting pressure, total length, intraabdominal length, (b) impedance-pH results:% time pH<4 (upright, recumbent, total), number of reflux episodes (acid, nonacid, total) in upright and recumbent position. Association was evaluated by Pearson correlation.
Results: 154 patients were included: 35% male, mean age 53.5 years, mean BMI = 30 (range: 18–55). 39% patients obese (BMI > 30), 34% overweight (BMI 25–29.9), 27% normal (BMI < 25). 74% patients tested on acid suppressive therapy (rest off medication). Correlations between BMI and evaluated variables shown in the table. There was a significant but weak positive correlation between BMI and total number of reflux episodes (r = 0.163, P= 0.04); BMI did not correlate with% time pH < 4 (possibly because most patients were tested on acid suppressive medication). BMI did not correlate with LES resting pressure, total length, or intraabdominal length.
Conclusion: Our data shows a positive correlation between BMI and total number of reflux episodes (acid + nonacid). BMI does not correlate significantly with LES pressure or intraabdominal length, suggesting that the increased reflux may be TLESR mediated because basal LES conditions do not appear to be affected.