Normative high resolution esophageal manometry values in asymptomatic patients with obesity

Surgical bariatric interventions, while highly effective, can be associated with post-operative esophageal symptoms, gastroesophageal reflux disease and esophageal dysmotility. Whether pre-operative physiology impacts this risk is unknown, in part because expected values on esophageal manometry in patients with obesity are not well understood. This study seeks to establish normative values on esophageal high resolution manometry (HRM) and the prevalence of esophageal dysmotility in the asymptomatic patient with obesity.

This retrospective study included adult patients with body mass index (BMI) ≥35 kg m^-2 without esophageal symptoms undergoing preoperative bariatric surgical evaluation, including HRM, at a single tertiary care center between February, 2019 and February, 2020.

Of 104 asymptomatic patients with obesity, HRM identified normal esophageal motility in 94 (90.4%) with the remaining 10 having ineffective esophageal motility (3.8%), manometric esophagogastric junction outflow obstruction (3.8%), distal esophageal spasm (1.0%), and hypercontractile esophagus (1.0%). Mean of median lower esophageal sphincter integrated relaxation pressure (LES IRP) was 10.6 mmHg supine (95th percentile 21.5 mmHg) and 8.5 mmHg upright (95th percentile 21.3 mmHg). 86% of patients had intragastric pressure above 8 mmHg. Mean of mean distal contractile integral (DCI) was 2261.6 mmHg cm s^-1 (95th percentile 5889.5 mmHg cm s^-1).

The vast majority of asymptomatic patients with obesity had normal manometry. LES IRP and DCI were higher than that observed in non-obese cohorts. Additionally, BMI correlated to increased intragastric pressure. These data suggest that normative values in patients with obesity should be adjusted to prevent overdiagnosis of EGJOO or hypercontractile esophagus.