Variable abnormal physiological motility in the proximal upper gastrointestinal tract in gastroparesis

Background Traditional testing for gastroparesis with gastric emptying scintigraphy (GES) likely misses a subset of patients because of the heterogeneous nature of the disease. The primary aim of this study is to determine the prevalence of simultaneously measured transit and pressure abnormalities in patients with gastroparesis. The secondary aim is to assess diagnostic gain realized by measuring antroduodenal pressure and gastric transit with wireless motility capsule (WMC) compared to gastric transit measured by GES. Identification of abnormalities beyond gastric transit delay in gastroparesis may yield novel targets for pharmacological therapies. Methods Forty-three subjects with symptoms of gastroparesis and previous abnormal GES within 2 years were enrolled in the study. Subjects underwent simultaneous GES and WMC to assess gastric transit. Gastric and small bowel pressure profiles were measured by WMC to determine the contribution of pressure to diagnostic gain realized with WMC. Key Results Fifty-one percent of subjects had abnormal GES while 70% of subjects had either abnormal gastric emptying time (GET) or antroduodenal pressure. Gastric emptying time was abnormal in 60% of subjects while gastric or small bowel pressure was abnormal in 47% of subjects. The overall diagnostic gain of WMC compared to GES was 19% (P = 0.04). Seven percent of subjects had abnormal small bowel pressure profiles when both GES and GET were normal. Conclusions & Inferences (i) Gastroparesis is a heterogeneous disorder and testing only solid food emptying by scintigraphy may miss a significant amount of pathology. (ii) Measuring complementary aspects of gastric and small bowel function simultaneously results in greater detection of physiologic abnormalities that may underlie patient symptoms.