Gastric dysfunction in patients with chronic nausea and vomiting syndromes defined by a noninvasive gastric mapping device

Abstract

Chronic nausea and vomiting syndromes (NVSs) are prevalent and debilitating disorders. Putative mechanisms include gastric neuromuscular disease and dysregulation of brain-gut interaction, but clinical tests for objectively defining gastric motor function are lacking. A medical device enabling noninvasive body surface gastric mapping (BSGM) was developed and applied to evaluate NVS pathophysiology. BSGM was performed in 43 patients with NVS and 43 matched controls using Gastric Alimetry (Alimetry), a conformable high-resolution array (8 × 8 electrodes; 20-mm interelectrode spacing), wearable reader, and validated symptom-logging app. Continuous measurement encompassed a fasting baseline (30 minutes), 482-kilocalorie meal, and 4-hour postprandial recording, followed by spectral and spatial biomarker analyses. Meal responses were impaired in NVS, with reduced amplitudes compared to controls (median, 23.3 microvolts versus 38.0 microvolts, P < 0.001), impaired fed-fasting power ratios (1.1 versus 1.6, P = 0.02), and disorganized slow waves (spatial frequency stability, 13.6 versus 49.5; P < 0.001). Two distinct NVS subgroups were evident with indistinguishable symptoms (all P > 0.05). Most patients (62%) had normal BSGM studies with increased psychological comorbidities (43.5% versus 7.7%; P = 0.03) and anxiety scores (median, 16.5 versus 13.0; P = 0.035). A smaller subgroup (31%) had markedly abnormal BSGM, with biomarkers correlating with symptoms (nausea, pain, excessive fullness, early satiety, and bloating; all r > 0.35, P < 0.05). Patients with NVS share overlapping symptoms but comprise distinct underlying phenotypes as revealed by a BSGM device. These phenotypes correlate with symptoms, which should inform clinical management and therapeutic trial design.

Non-invasive thoracoabdominal mapping of post-oesophagectomy conduit function

“…Additionally, meal sizes were reduced by 50% vs the standard Gastric Alimetry test to account for the reduced gastric remnant volume, which is considered adequate to stimulate gastric activity (6).…”

“…The copyright holder for this preprint this version posted January 11, 2023. ; https://doi.org/10.1101/2023.01.10.23284370 doi: medRxiv preprint Additionally, meal sizes were reduced by 50% vs the standard Gastric Alimetry test to account for the reduced gastric remnant volume, which is considered adequate to stimulate gastric activity (6).…”

“…The copyright holder for this preprint this version posted January 11, 2023. ; https://doi.org/10.1101/2023.01.10.23284370 doi: medRxiv preprint operative studies (6,11). Emerging spatial mapping techniques will also allow determination of electrical propagation patterns in future studies (9).…”

“…With feasibility established, future studies can now be conducted applying this technique on larger cohorts of patients after oesophagectomy. Such work will enable improved characterisation of pathophysiology and symptom correlations, in order to guide therapeutic decisions, as is being performed in other gastric disorders (6). In addition, the new test is also now being evaluated for its potential in gastric dysfunction after pancreaticoduodenectomy (20).…”

Exploring the Gut-Brain Connection in Gastroparesis with Autonomic and Gastric Myoelectric Monitoring

“…One of the barriers to in-depth characterization of the gut-autonomic connection in gastroparesis is a lack of multimodal ambulatory monitoring of electrophysiological activity at high temporal resolution with respect to the autonomic nervous system and digestive activity. Previous studies attempting to characterize autonomic and digestive activity in gastroparesis were either not ambulatory, not at a high temporal resolution, not high-quality in terms of physiologically and statistically rigorous methods, or not multimodal [1][2][3][4][5][6][7][8][9][10][11][12]. Several of the aforementioned autonomic studies have focused on heart rate variability, an important marker of autonomic tone [13].…”