P0401 - Roles of Swallowing and Belching in Different Phenotypes of Gastroesophageal Reflux Disease

Sunday, October 22, 2023

3:30 PM – 7:00 PM PT

Location: Exhibit Hall

Presenting Author(s)

David Brand, MD (he/him/his)

New York Presbyterian-Columbia

David Brand, MD, David A.. Katzka, MD
New York Presbyterian-Columbia, New York, NY

Introduction: The roles of swallowing and belching in the pathogenesis of gastroesophageal reflux disease (GERD) remain unclear, both generally and in specific GERD phenotypes.

Methods: This study retrospectively analyzed pH/impedance studies to compare reflux events preceded by gastric and supragastric belching and by air and liquid/solid swallowing between groups based on reflux position, lower esophageal sphincter (LES) pressure, and acid exposure time (AET). ANOVA, two-sample t tests, and linear regression testing were used for analyses.

Results: 30 patients were included in the study (20 experimental, 10 controls without GERD). Findings are in Table 1.

Between position groups, the upright and control groups had a higher proportion of reflux events with a preceding swallow or belch (0.64) than the supine group (0.38) (p=0.043). The upright group also trended toward a higher proportion of events preceded by overall swallowing (0.61) than the supine group (0.32) and controls (0.50) (p=0.064), but the three groups had similar rates of preceding air (0.55, 0.31, 0.48, p=0.11) and liquid/solid swallowing (0.032, 0.024, 0.017, p=0.69). LES pressure did not correlate with reflux events preceded by air (R²=0.0020, p=0.81), liquid/solid (R²=0.079, p=0.13), or overall swallowing (R²=0.021, p=0.44). There was no difference in the rate of events preceded by gastric, supragastric, and overall belching between upright (0.032, 0.028, 0.060) and supine groups (0.066, 0.015, 0.075) (p=0.25, 0.46, 0.62), and LES pressure did not correlate with the rate of events preceded by gastric (R²=0.011, p=0.57), supragastric (R²=0.083, p=0.12), or overall belching (R²=0.000093, p=0.96).

Between AET groups, patients with normal/likely normal AET had a higher rate of events preceded by gastric and overall belching (0.12, 0.12) than those with increased acid exposure (0.030, 0.057, p=0.0083, 0.054), but the two groups had similar rates of preceding air (0.43, 0.47, p=0.68), liquid/solid (0.018, 0.032, p=0.30), and overall swallowing (0.44, 0.53, p=0.38). AET did not correlate with events preceded by gastric (R²=0.047, p=0.25), supragastric (R²=0.0012, p=0.85), or overall belching (R²=0.065, p=0.17), or with events preceded by air (R²=0.0019, p=0.82), liquid/solid (R²=0.0019, p=0.82), or overall swallowing (R²=0.0033, p=0.76).

Discussion: Swallowing more than belching is a dominant mechanism for reflux irrespective of GERD position, LES pressure, and AET.

	Proportion of Reflux Events Preceded by Behavior
Behavior	Upright GERD	Supine GERD	No GERD	p value	Increased AET	Normal/likely normal AET	p value
Air swallowing	0.55	0.31	0.48	0.11	0.47	0.43	0.68
Liquid/solid swallowing	0.032	0.024	0.017	0.70	0.032	0.018	0.30
Overall swallowing	0.61	0.32	0.50	0.064	0.53	0.44	0.38
Gastric belching	0.032	0.066	0.14	0.049	0.030	0.12	0.0083
Supragastric belching	0.028	0.015	0.0036	0.25	0.027	0.0055	0.091
Overall belching	0.060	0.075	0.14	0.14	0.057	0.12	0.054
Swallowing or belching	0.64	0.38	0.64	0.043	0.48	0.64	0.10
No preceding event	0.36	0.59	0.36	0.062	0.44	0.43	0.89

Table: Table1. Comparison of the proportion of reflux events preceded by different behaviors between position and AET groups.

Disclosures:

David Brand indicated no relevant financial relationships.

David Katzka: Medtronic – Grant/Research Support.

David Brand, MD, David A.. Katzka, MD. P0401 - Roles of Swallowing and Belching in Different Phenotypes of Gastroesophageal Reflux Disease, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.