The application of Chicago classification 4.0 in esophageal motility disorders of scleroderma: a case-control study in China

Background Systemic sclerosis (SSc) is a rare autoimmune connective tissue disease characterized by multi-organ fibrosis and vasculopathy that frequently involves the esophagus. This study assessed esophageal motility disorders in patients with SSc using High-resolution manometry (HRM) and classified these disorders according to the Chicago Classification version 4.0, aims to investigate the associations between esophageal dysfunction and clinical phenotypes in Chinese SSc patients, while exploring potential modifications to enhance the applicability of the Chicago v4.0 protocol in SSc patients. Methods We retrospectively identified SSc patients fulfilling 2013 ACR criteria who underwent HRM classified by Chicago v4.0 at our center (2021–2023). Demographics, organ involvement, pulmonary-function tests, echocardiography and reflux symptom scores (RDQ/GERDQ) were extracted from the hospital information system; age and sex matched non-SSc HRM subjects served as controls. Associations between Chicago categories and clinical variables were examined by multinomial logistic regression. Results In our study, esophageal motility disorders were present in 76.7% of patients with systemic sclerosis, predominantly characterized by ineffective esophageal motility (IEM) (35%) and absent contractility (AC) (36.67%). The occurrence rate of AC rose with age. Symptoms of gastroesophageal reflux were more common in the AC group [Odds Ratio: 3.23 (1.02-10.22) vs 1.43(0.52-3.95), P<0.05, E value=2.99]. Diffusion capacity for carbon monoxide (DLCO) was significantly reduced in both IEM and AC (-2.03 vs -2.70, P value<0.05), with a more pronounced decrease in AC. Total lung capacity (TLC) and forced expiratory volume in one second (FEV1) exhibited stronger associations with AC (-1.04 and -0.8 respectively, p value<0.05). Upright HRM revealed more marked decreases in EGJ pressure and distal contractile integral (DCI) relative to the supine position in SSc patients, indicating that esophageal abnormalities may be more readily apparent during upright examination. Conclusions Esophageal motility disorders in SSc were common and significantly associated with older age, gastroesophageal reflux symptoms, and reduced lung function. Future studies are needed to clarify whether early esophageal motility disorders are associated with disease progression and prognosis in patients.