Publication:

High-resolution manometry thresholds and motor patterns among asymptomatic individuals.

Objective: High-resolution manometry (HRM) is the current standard for characterization of esophageal body and esophagogastric junction (EGJ) function. We aimed to examine the prevalence of abnormal esophageal motor patterns in health, and to determine optimal thresholds for software metrics across HRM systems. Design: Manometry studies from asymptomatic adults were solicited from motility centers worldwide, and were manually analyzed using integrated relaxation pressure (IRP), distal latency (DL), and distal contractile integral (DCI) in standardized fashion. Normative thresholds were assessed using fifth and/or 95th percentile values. Chicago Classification v3.0 criteria were applied to determine motor patterns across HRM systems, study positions (upright vs supine), ages, and genders. Results: Of 469 unique HRM studies (median age 28.0, range 18-79 years). 74.6% had a normal HRM pattern; none had achalasia. Ineffective esophageal motility (IEM) was the most frequent motor pattern identified (15.1% overall), followed by EGJ outflow obstruction (5.3%). Proportions with IEM were lower using stringent criteria (10.0%), especially in supine studies (7.1%-8.5%). Other motor patterns were rare (0.2%-4.1% overall) and did not vary by age or gender. DL thresholds were close to current norms across HRM systems, while IRP thresholds varied by HRM system and study position. Both fifth and 95th percentile DCI values were lower than current thresholds, both in upright and supine positions. Conclusions: Motor abnormalities are infrequent in healthy individuals and consist mainly of IEM, proportions of which are lower when using stringent criteria in the supine position. Thresholds for HRM metrics vary by HRM system and study position.