Solid food swallows of high-resolution manometry unmask esophageal hypomotility in GERD

Aim Gastroesophageal reflux disease (GERD) is closely linked to esophageal motility dysfunction. While high-resolution manometry (HRM) remains the gold standard for evaluating esophageal motility, the conventional single water swallow (SWS) protocol may not fully capture motility abnormalities. This study investigates esophageal motility characteristics in GERD patients using solid food swallows (SFS) to better assess clinically relevant dysfunction.Methods Esophageal motility parameters were compared between GERD and non-GERD groups during both SWS and SFS. Correlations between SFS findings and dysphagia symptoms, endoscopic findings and reflux metrics were analyzed, followed by multivariate regression to identify independent GERD risk factors.Results Among 151 participants, 54 were diagnosed with GERD. Impaired SFS esophageal body motility was more prevalent in GERD versus non-GERD patients (p < 0.01). Moreover, the GERD group exhibited significantly higher rate of esophageal hypomotility during SFS compared to SWS (p < 0.001). With SFS testing, 35.2% (19/54) of GERD with normal SWS esophageal motility demonstrated Impaired SFS esophageal body motility. Multivariate analysis identified SFS esophageal body hypomotility (OR: 5.158, 95%CI: 2.439–10.909, p < 0.001) as independent GERD predictors. The prevalence of dysphagia symptom and esophagitis were higher in patients with esophageal hypomotility of SFS. Distal contractile integral of SFS positively correlated with mean nocturnal baseline impedance (r = 0.393), while inversely correlating with supine bolus clearance time (r=-0.326) and acid exposure (r=-0.403).Conclusions SFS unmask clinically significant esophageal dysmotility in GERD patients that SWS miss, revealing pathophysiology linked to prolonged acid exposure and mucosal injury. SFS-enhanced HRM protocols may improve GERD evaluation and risk stratification.