Enteric Dysmotility/ Acquired Chronic Intestinal Pseudo-Obstruction (ED/CIPO) – Relationship Between Symptoms, Small Intestinal Manometric Abnormalities and Neurohistological Findings

Abstract

Background: Presenting symptoms of gastroparesis include nausea, vomiting, bloating, fullness, and pain. Large studies show inconsistent relations of any symptom with delayed gastric emptying of digestible solids on scintigraphy. Wireless motility capsules (WMC) quantify indigestible gastric emptying and gastrointestinal pressure activity. Relations of gastroparesis symptoms to WMC emptying and pressure parameters are unexplored. Aims: Relate gastroparesis symptoms to (i) WMC gastric emptying times, (ii) gastric contractions during different times of the emptying period, and (iii) small intestinal contractions.Methods: 45 patients with prior scintigraphy diagnosis of gastroparesis from 7 centers underwent concurrent 4 hr gastric scintigraphy and WMC testing (SmartPill Corp.). Patients were stratified into normal ( 5 hr). Numbers of gastric contractions/hr and motility indices (MI=ln[1 + sum of amplitudes x no. contractions]) were quantified from (i) WMC ingestion to t1/2 of scintigraphy emptying (1st half of digestible gastric emptying), (ii) t1/2 to t90% (2nd half of digestible emptying), and (iii) the hr before emptying (indigestible emptying). Numbers of small intestinal contractions and MI were quantified in the hr after gastric emptying. Subscales (0=none, 5=very severe) for nausea/ vomiting, bloating, fullness, and upper and lower abdominal pain were calculated from 20 question surveys on study day. Results:No symptom subscales were increased in association with delayed vs. normal WMC gastric emptying and correlations of emptying times with N/V (r=-0.17), fullness (r=0.10), bloating (r=-0.08), and upper pain (r=-0.20) subscales were poor. Gastric hypomotility did not relate to greater symptoms. Rather, N/V scores trended higher with gastric contraction numbers >30/hr in the 2nd half of digestible emptying (2.5±1.6 vs. 1.4±0.8, P=0.06) and were greater with gastric MI >10.5 in the hr before WMC emptying (2.6±1.5 vs. 1.5±1.0, P=0.03). Increased contractility in the stomach or intestine was not associated with pain. Instead, lower pain scores were reduced with small intestinal contractions >60/hr (1.2±1.2 vs. 2.2±1.4, P=0.03) and MI >11.5 (1.1±1.2 vs. 2.3±1.3, P= 0.01). Conclusions: As observed in large studies using scintigraphy, symptoms of gastroparesis correlated poorly with gastric emptying measured by wireless motility capsules in this small study. Likewise, gastric hypomotility measured by WMC pressure parameters did not relate to any symptom subscale in gastroparesis. Associations of increased gastric contractions with nausea and vomiting and reduced intestinal contractions with lower abdominal pain are of uncertain importance. These observations mandate performance of a much larger study in a standardized gastroparesis population to carefully relate validated symptom scores to WMC results.