S1083 Abnormalities in Regional Gut Transit Correspond Poorly With Presenting Gastrointestinal Symptoms

Introduction: Gastrointestinal (GI) dysmotility often results in abnormal transit times in multiple regions of the gut. The location and distribution of dysmotility is important for appropriate clinical management, however, symptoms alone do not accurately predict delays or their location. The Atmo Capsule is a novel diagnostic tool that can be used to objectively measure regional gut transit times in a single test. We evaluated the relationship between patients’ presenting symptoms and objectively measured GI transit time data from the Atmo Capsule across different regions of the GI tract. Methods: 209 patients with suspected GI dysmotility underwent evaluation with the Atmo Capsule. This analysis utilized data from 171 patients without protocol deviations who had valid transit measurements for all regions of the gut. Patients were categorized based on symptoms as having suspected upper GI (e.g., postprandial fullness, nausea; n = 44), lower GI (e.g., chronic constipation per ROME IV criteria; n = 15), or pan-GI dysmotility (n = 112). Regional transit times were considered delayed as follows: gastric emptying ≥5 h; small bowel transit, ≥6 h; colonic transit, ≥59 h. Results: Delayed transit times were identified in 59% of patients (101/171). Of those, 33% had transit delays affecting multiple GI regions. Patients with symptoms leading to suspicion for isolated upper or lower GI dysmotility often had transit delays beyond the suspect region. Specifically, only 14% (6/44) of patients with suspected upper GI dysmotility had isolated delayed gastric emptying; similarly, only 20% (3/15) of those with suspected lower GI dysmotility had isolated delayed colonic transit. Among patients with suspected pan-GI dysmotility, only 20% (22/112) had multi-regional transit delays. Conclusion: Presenting symptoms poorly predicted the presence and distribution of transit time abnormalities. Objective testing with the Atmo Capsule revealed that transit time delays rarely corresponded to the region of suspected dysmotility and often affected multiple regions of the gut. These findings indicate that symptoms are poorly predictive of location of transit delay thus supporting the value of objective assessments of whole-gut transit and raise the possibility that other factors may be involved in symptom generation.