Nutrient Drink Test to Assess Gastric Accommodation in Cyclic Vomiting Syndrome: Single-blinded Parallel Grouped Prospective Study

BACKGROUND/AIMS: Cyclic vomiting syndrome (CVS) is characterized by episodes of nausea and vomiting, separated by symptom-free intervals. The pathogenesis of CVS is poorly understood. Limited data exist on evaluating impaired gastric accommodation as a mechanistic means for symptoms. We aim to determine if CVS patients demonstrate impaired gastric accommodation applying a nutrient drink test (NDT) protocol. METHODS: Through this single-blinded pilot clinical trial, patients with CVS per Rome IV critera and healthy controls were assessed for presence of impaired gastric accommodation by administering an established NDT protocol. Statistical analysis was performed, with data presented as medians and interquartile range. RESULTS: Eleven CVS patients and 15 healthy controls participated in the study between January 2018 and October 2018. Median age was 42.0 years and 37.0 years; majority of subjects were female, 72.7% and 73.3%, respectively. Demographics were similar between CVS and healthy controls. Almost all healthy controls (93.3%) ingested the complete 500 mL protocol, whereas a smaller proportion (72.7%) were able to complete all 4 doses in the CVS group (P = 0.188). Post-prandial visual analogue scale scores of nausea and abdominal pain were found to be significantly higher in CVS patients compared to healthy controls. CONCLUSIONS: To our knowledge, this is the first NDT protocol in CVS evaluating the role of impaired gastric accommodation and hypersensitivity as a possible pathophysiologic mechanism. Findings from this study suggest the presence of gastric hypersensitivity in a subset of CVS patients. These results provide the foundational data necessary for future larger testing of NDT and diagnostic accuracy in CVS.