Ineffective Esophageal Motility and Its Predictors in Gastroesophageal Reflux Disease Patients With Pathologic Acid Exposure Time

Background/aims: : Although gastroesophageal reflux disease (GERD) and ineffective esophageal motility (IEM) often coexist, the directionality of their relationship remains uncertain. Clarifying physiological predictors of IEM in GERD patients with objectively verified pathological acid exposure may facilitate more personalized treatment strategies.

Methods: : This retrospective analysis included 289 patients with typical reflux symptoms and abnormal acid exposure (acid exposure time > 6%) confirmed by 24-hour pH-impedance monitoring. Esophageal motility was assessed using high-resolution manometry, while mucosal integrity was evaluated through distal mean nocturnal baseline impedance (MNBI). Patients were categorized into normal motility and IEM groups. Clinical, endoscopic, manometric, and impedance parameters were compared between the groups.

Results: : IEM was identified in 41.5% of patients. Compared with those showing normal motility, the IEM group was older (median 51.5 vs 44 years, P < 0.001), had reduced lower esophageal sphincter (LES) pressure (15 vs 19 mmHg, P = 0.006), and exhibited decreased distal MNBI (1300 vs 1780 Ω, P = 0.005). Multivariate regression revealed prolonged upright bolus exposure, reduced LES pressure, delayed supine distal latency, and MNBI < 1500 Ω as independent predictors of IEM. No significant associations were observed with diabetes or Helicobacter pylori infection.

Conclusions: : In GERD patients with confirmed pathological acid exposure, IEM is common and associated with weakened LES pressure, delayed peristalsis, and reduced mucosal integrity. The link between low MNBI and IEM suggests an interaction between epithelial barrier dysfunction and esophageal motility, emphasizing the need for comprehensive functional evaluation in GERD management.