Liquid nutrient drink testing induces gastric myoelectrical abnormalities that correlate with gastroduodenal symptoms

Chronic gastroduodenal symptoms experienced in functional dyspepsia, chronic nausea and vomiting syndromes, and gastroparesis affect over 10% of the global population and impose a significant healthcare burden. The relationship between aberrant gastric myoelectrical activity and symptom genesis remains incompletely defined. In this study, we evaluated the effects of gastric distension induced by a liquid nutrient drink test (LNDT) on gastric myoelectrical activity in healthy volunteers using noninvasive body surface gastric mapping (BSGM) with the Gastric Alimetry system (Auckland, New Zealand). Twenty healthy participants (10 females) underwent BSGM with 30-min fasting baseline, LNDT with Ensure administered at 30 mL/min until maximal toleration, and 4-h postprandial recording. Gastric Alimetry Rhythm Index (GA-RI), principal gastric frequency (PGF), and BMI-adjusted amplitude were analyzed across time and in relation to symptoms using mixed models. During LNDT, PGF decreased significantly (2.7 ± 0.2 vs. an overall average 3.0 ± 0.2 cycles/min, <i>P</i> < 0.001) and GA-RI declined (β = -0.11, 95% CI -0.21 to -0.002, <i>P</i> = 0.047) with a concurrent increase in nausea ratings. In the first postprandial hour, bloating, nausea, and overall symptom burden were elevated, with sustained reductions in GA-RI and PGF correlating with higher symptom scores. Spectral analyses revealed transient abnormalities temporally aligned with symptom genesis. These findings indicate that excessive gastric distension provokes aberrant gastric myoelectrical activity that is closely associated with foregut symptoms, supporting the role of these abnormalities in the pathophysiology of neurogastroduodenal disorders.<b>NEW & NOTEWORTHY</b> Body surface gastric mapping with liquid nutrient drink test found that excessive gastric distension provokes dysrhythmias that are closely associated with foregut symptoms, supporting the role of disrupted gastric myoelectrical function in the pathophysiology of neurogastroduodenal disorders.