From Chicago classification v3.0 to v4.0: Diagnostic changes and clinical implications

Background The Chicago Classification (CC) used to define esophageal motility disorders in high-resolution manometry (HRM) has evolved over time. Our aim was to compare the frequency of motility disorders diagnosed with the last two versions (CCv3.0 and CCv4.0) and to evaluate symptoms severity according to the diagnoses. Methods From June to December 2020, patients who underwent esophageal HRM with swallows in supine and sitting positions were included. HRM studies were retrospectively analyzed using CCv3.0 and CCv4.0. Symptoms severity and quality of life were assessed with validated standardized questionnaires. Key Results Among the 130 patients included (73 women, mean age 52 years), motility disorder diagnoses remained unchanged in 102 patients (78%) with both CC. The 3 patients with esophago-gastric junction outflow obstruction (EGJOO) with CCv3.0 were EGJOO, ineffective esophageal motility (IEM) and normal with CCv4.0. Twenty-four out of 63 IEM diagnosed with the CCv3.0 (38%) turned into normal motility with the CCv4.0. Whatever the CC used, brief esophageal dysphagia questionnaire score was significantly higher in patients with EGJ relaxation disorders compared to those with IEM (25 (0-34) vs 0 (0-19), p = 0.01). Gastro-Esophageal Reflux disease questionnaire (GERD-Q) score was higher in patients with IEM with both CC compared to those who turned to normal with CCv4.0. Conclusions and Inferences While motility disorders diagnoses remained mainly unchanged with both CC, IEM was less frequent with CCv4.0 compared to CCv3.0. The higher GERD-Q score in IEM patients with CCv4.0 suggests that CCv4.0 might identify IEM more likely associated with GERD.