Ineffective esophageal motility (IEM) is a rare motility disorder characterized by weak or failed peristalsis at high-resolution manometry (HRM).  There is an established association between IEM and gastroesophageal reflux-disease (GERD) symptoms. However, it is unclear why some patients present with dysphagia. In this study we aimed to investigated whether dysphagia in IEM is associated with specific HRM or pH-impedance monitoring (MII-pH) findings.

Adults (≥18 y) who underwent HRM for upper gastrointestinal symptoms who were diagnosed with IEM according to Chicago v4.0 between January 2021 and November 2024 were included. Patients’ gender, age, symptoms (dysphagia, chest pain, heartburn, regurgitation, belching), response to proton pump inhibitor (PPI) treatment, and HRM data were recorded. All patients underwent MII-pH. Wilcoxon rank sum test, Pearson's chi-squared test and Fisher's exact test were used for comparisons. Significance was set at p<0.05.  

In the study period, 54 patients were diagnosed with IEM. Of them, 33 (61%) did not report dysphagia (IEM-GERD), while 21 (39%) had dysphagia (IEM-DYSPHAGIA). Of note, patients with or without dysphagia had a comparable prevalence of heartburn, chest pain, regurgitation, and erosive esophagitis. In addition, IEM-GERD and IEM-DYSPHAGIA were comparable in age and response to PPI treatment. IEM-GERD and IEM-DYSPHAGIA did not show significant differences in EGJ type, EGJ contractile integral (EGJ-CI), integrated relaxation pressure (IRP), percentage of ineffective or failed swallows, or the rapid drinking challenge (RDC) findings (p>0.05 for all), demonstrating an overall similar pathophysiology of peristalsis and EGJ opening. In terms of MII-pH, there was no statistical difference in GERD-related parameters between IEM-GERD and IEM-DYSPHAGIA, who showed comparable values of acid exposure time (AET), mean nocturnal baseline impedance (MNBI), symptom association indexes, and post-reflux swallow-induced peristaltic wave index (PSPW-I) (p>0.05 for all). 

We showed that dysphagia in IEM is not explained by impaired EGJ outflow or worse peristalsis. IEM with and without dysphagia have a similar proportion of GERD symptoms, comparable MII-pH findings, and respond similarly to PPI treatment. Our findings suggest that dysphagia in IEM could be a symptomatic manifestation of GERD.