Thomas L. Abell

Introduction: Although pain is recognized as an important symptom in gastroparesis, it has not been well studied and characterized. Quantitative sensory testing (QST) is a psychophysical method that has the potential to provide a measure of pain processing, as well as insight into pain pathophysiology and the prediction of response to specific therapies. We aimed to characterize somatic QST in a well‐characterized cohort of patients with gastroparesis. Methods: Adults with scintigraphically defined gastroparesis underwent abdominal QST with assessment of mechanical pain: pain sensitivity (thresholds and tolerance) and pain facilitation (temporal summation). The Patient Assessment of Upper GI Symptoms (PAGI‐SYM) upper and lower abdominal pain scales were used. Results: QST was performed on 264 participants (87% female; age = 18–78 years). In both the upper and lower abdomen, smaller pain thresholds and lower pain tolerance were significantly associated with greater PAGI‐SYM upper abdominal pain severity ( b 's = 0.07–0.15; p 's = 0.007–0.02), but not lower abdominal pain severity. Scores on the PAGI‐SYM upper and lower abdominal pain scales were moderately correlated ( r = 0.48, p < 0.0001). No significant associations were found for temporal summation. Conclusions: Our findings suggest self‐reported upper abdominal pain severity correlated with both lower and upper abdominal mechanical pain sensitivity—possibly reflecting secondary sensitization of the abdominal wall, due to viscerosomatic convergence in upper abdominal somatic segments. Lower abdominal pain severity association with only upper (but not lower) abdominal QST may be due to cross‐organ sensitization. Further investigations are needed to test the clinical utility of abdominal QST in gastric sensorimotor disorders. Trial Registration: ClinicalTrials.gov : NCT01696747

Background/Objectives: Gastroparesis is a disorder in which individuals experience dysfunctional gastric motor symptoms, but the underlying etiology is unclear. This exploratory study investigates autoimmune, inflammatory, metabolic, autonomic, and enteric (AIMAE) abnormalities in patients with gastroparesis symptoms to provide new insights into pathophysiology. The aim of this study is to further elucidate the potential associations between the different AIMAE measurements. Methods: Twenty-one patients with gastroparesis symptoms underwent a series of testing including assays for measurement of autoimmune, inflammatory, and metabolic markers; measurement of the autonomic nervous system; electrogastrography recordings; and gastric emptying measurements. Associations were evaluated using Spearman’s rank correlation with pairwise-complete observations. Benjamini–Hochberg false-discovery-rate correction was applied separately within each prespecified statistical family, with q ≤ 0.05 defining statistical significance. Results: Across 3432 planned correlations in 10 prespecified families, four associations met the false-discovery-rate threshold. DFS-70 was positively associated with C-peptide (q= 0.000330). Low-resolution EGG S1 mean amplitude was positively associated with insulin (q = 0.000172). IL-6 was inversely associated with baseline sympathetic LFa modulation (q = 0.000172) and standing sympathetic LFa modulation (q = 0.000172). Conclusions: This prospective pilot study identified strong associations among autoimmune, inflammatory, metabolic, enteric, and autonomic measurements. The findings were robust to leave-one-out analyses and generally retained their direction and magnitude after excluding participants with diabetes or a gastric electrical stimulator. However, the results of this study should be interpreted as hypothesis-generating rather than causal due to its limitations including a small cohort and incomplete confounder information.

Objectives: Bioelectric devices such as gastric electrical stimulation (GES) are used to treat severe upper gastrointestinal motility disorders in both younger and older patients. We compared clinical, physiologic, quality of life, and full‐thickness gastric biopsy results between younger and older patients undergoing GES. Methods: We analyzed 245 patients (45 males, 200 females; median age 42 [range 2–80 years] 47.6% with delayed solid gastric emptying and 52.4% nondelayed). All patients underwent temporary GES trials, followed by full‐thickness gastric biopsies and physiologic assessments during permanent GES placement. Histologic evaluation used standardized cellular markers. Validated patient‐reported outcomes were assessed at baseline and 1 year, with a 1‐point improvement as clinical success. Results: Younger patients ( n = 37; 9 males, 28 females; median age 17 [range 2–25 years]); reported less severe anorexia (3.0 vs. 3.5, p = 0.005) and bloating (2.0 vs. 3.5, p < 0.001) at baseline, while nausea and vomiting severity were similar to 208 older adults. Biopsy analysis showed fewer CD3+ and CD8+ cells in younger patients ( p = 0.032 and p = 0.002) and fibrosis was more common in older adults (41.2% vs. 16.1%, p = 0.008). Conclusion: Younger patients with gastroparesis (Gp) syndromes have full‐thickness gastric biopsy abnormalities and clinical measures that are similar, but not identical to older patients. These findings indicate the need for broader use of tissue analysis and other clinical measures in severely symptomatic patients with Gp symptoms undergoing the bio‐electric therapy of gastric electrical stimulation to optimize perioperative counseling and postoperative symptom management.

Background Nausea and vomiting, whether acute or chronic, often result from disturbances in the central, autonomic, and enteric nervous systems. Both space motion sickness and gastrointestinal motility disorders share overlapping mechanisms involving autonomic dysfunction, abnormal gastric myoelectric activity, and delayed gastric emptying. Conventional medical and surgical treatments often provide incomplete relief or cause undesirable side effects, which has encouraged investigation into nonpharmacologic approaches. Aims This study evaluates the therapeutic potential of Autogenic Feedback Training Exercise, a behavioral intervention developed by the National Aeronautics and Space Administration, as an adjunctive treatment for patients with gastrointestinal motility disorders and related autonomic dysfunction. Methods Findings from clinical and experimental research involving astronauts, pilots, and individuals with gastrointestinal motility disorders were reviewed. The training combines cognitive imagery and biofeedback techniques to help subjects voluntarily regulate physiological responses such as heart rate, blood pressure, and skin conductance. Sessions typically last thirty minutes and include alternating relaxation and arousal exercises over several weeks. Results Autogenic Feedback Training Exercise increased motion sickness tolerance and reduced sympathetic activation while improving physiological stability. In individuals with gastrointestinal motility disorders, it enhanced gastric emptying, improved electro gastrographic activity, and lessened symptom severity, particularly in those with mild to moderate delay in gastric emptying. When combined with gastric electrical stimulation, outcomes further improved through enhanced autonomic and enteric regulation. Conclusions Autogenic Feedback Training Exercise offers a promising, noninvasive approach for restoring autonomic balance and improving gastrointestinal function. Remote delivery through telemedicine may expand access for patients with chronic illness.

Background: Gastroparesis is common in patients with diabetes. However, treatment options for diabetic gastroparesis are limited. Transcutaneous electrical acustimulation (TEA), a noninvasive method of delivering electrical stimulation via surface electrodes placed at certain acupuncture points that are in the vicinity of peripheral nerves, has been reported to exert therapeutic effects in patients with gastroesophageal reflux, functional dyspepsia, and constipation. The aim of this study was to explore the therapeutic potential of TEA for diabetic gastroparesis. Methods: Eighteen patients with diabetes were enrolled in a single‐center, placebo‐controlled, randomized and crossover trial with TEA and sham‐TEA. TEA was performed twice daily after lunch and dinner via acupoints, ST36 (below the kneecap in the vicinity of the peroneal, sciatic, and tibial nerves) and PC6 (wrist above the median nerve) for 4 weeks. A set of parameters previously reported to improve gastrointestinal motility was used for both TEA and sham‐TEA (delivered via sham‐points). The gastroparesis cardinal symptom index was used to assess symptoms. The electrogastrogram (EGG) was used to assess gastric pace‐making activity (slow waves). Key Results: The TEA treatment improved each of the five major gastroparesis symptoms in comparison to baseline: nausea reduced by 29.7% ( p = 0.005), retching by 31.1% ( p = 0.006), vomiting by 39.3% ( p = 0.005), abdominal fullness by 21.4% ( p = 0.005), and bloating by 20.6% ( p = 0.006). There was also a significant improvement in the “pain interfering with activity” score with the 4‐week TEA treatment in comparison to baseline ( p = 0.046). TEA improved gastric pace‐making activity, reflected as a significant increase in the percentage of normal gastric slow waves in the postprandial state (69.5% ± 12.1% vs. 77.4% ± 16.5%, p = 0.039). Concurrently, TEA resulted in a trend of postprandial increase in vagal activity. Conclusions and Inferences: TEA at acupuncture points ST36 and PC6 with appropriate parameters is effective in treating the major gastrointestinal symptoms in patients with diabetic gastroparesis. Further pivotal studies are warranted to determine its clinical efficacies.

Background: Chronic gastroduodenal symptoms arise from heterogeneous gastric motor dysfunctions. This study applied multimodal physiological testing using gastric emptying scintigraphy (GES) with intragastric meal distribution (IMD) and Gastric Alimetry body surface gastric mapping (BSGM) to define motility and symptom associations. Methods: Patients with chronic gastroduodenal symptoms underwent simultaneous supine GES and BSGM with a 30 m baseline, 99mTC‐labeled egg meal, and 4 h postprandial recording. IMD (ratio of counts in the proximal half of the stomach to the total gastric counts) was calculated immediately after the meal (IMD0), with < 0.568 defining abnormal IMD. BSGM phenotyping followed a consensus approach, based on normative spectral reference intervals. Results: Among 67 patients (84% female, median age 40 years, median BMI 24 kg/m ² ), median IMD0 was 0.76 (IQR: 0.69–0.86) with 5 (7.5%) meeting abnormal IMD criteria. Delayed gastric emptying ( n = 18) was associated with higher IMD0 (median 0.9 vs. 0.7, p = 0.004). On BSGM, 15 patients had abnormal spectrograms (5 [7.5%] high frequency and 10 [14.9%] low rhythm stability and/or amplitude); and in these patients, higher IMD0 (proximal retention) strongly correlated to delayed BSGM meal responses ( R = −0.71, p = 0.003). Lower IMD, indicating antral distribution, correlated with higher gastric frequencies ( R = −0.27, p = 0.03). BSGM abnormalities paired with abnormal IMD were associated with worse dyspeptic symptoms. Conclusion: Proximal retention of food as assessed by IMD correlated with delayed emptying, and in the presence of neuromuscular spectral abnormalities (abnormal frequencies or rhythms), delayed motility responses on BSGM. Patients with multiple motor abnormalities experience worse dyspeptic symptoms.

Background: Chronic neurogastroduodenal disorders are challenging to manage, with therapy often initiated on a trial and error basis. Prokinetics play a significant role in management, but responses are variable and have been associated with adverse events, impacting widespread use. We investigated whether body surface gastric mapping (BSGM) biomarkers (using Gastric Alimetry) could inform patient selection for prokinetic therapy.Methods: Patients with chronic gastroduodenal symptoms taking oral prokinetic agents, regardless of gastric emptying status, were prospectively recruited and underwent BSGM (30 m baseline, 482 kcal standardized meal, 4 h postprandial recording) while off‐prokinetic agents. Patients were followed up with daily symptom diaries. A subset was compared to matched patients not taking prokinetic agents. Prokinetic responders were defined based on symptom improvement greater than a minimum clinically important difference methodology.Key Results: Forty‐two patients (88% female; median age 36; median BMI 26) taking prokinetics were analyzed. Prokinetic prescribing, compared to matched patients, was independent of BSGM metrics (p > 0.15). In patients on existing prokinetics (withheld for BSGM), lower amplitudes predicted reduced symptom burden, whereas low rhythm stability predicted a worse symptom burden (p < 0.05). In prokinetic‐naive patients (i.e., started on a prokinetic during the study), a lower postprandial amplitude predicted responders (mean 37.5 ± 10.6 uV in responders [n = 5] vs. mean 54.8 ± 6.6 uV among nonresponders [n = 3], p = 0.047).Conclusions: Gastric Alimetry biomarkers may help in the prediction of prokinetic response in patients with chronic gastroduodenal symptoms. Lower postprandial amplitudes, indicating a reduced meal response, appear to predict benefit, while impaired rhythm stability predicted poorer therapeutic response.

Introduction: Gastric electrical stimulation (GES) offers potential benefits for patients with drug-refractory gastroparesis syndromes (GpS). However, its impact on reducing hospital readmissions, particularly within 30 days post-discharge, remains unclear. GES placement might positively influence 30-day readmissions in patients frequently hospitalized for GpS symptoms. Methods: This prospective study included 110 patients admitted with GpS to a university-affiliated hospital over 5 years. The cohort had a mean age of 42 years. Hospital admissions were categorized into GpS-related flares and non-GpS-related causes. The Wilcoxon signed-rank test and generalized linear models (GLM) were used to compare pre-and post-GES outcomes. Results: The 110 patients had 1,690 admissions, of which 760 (45.0%) were related to GpS flare-ups. Less than 2% of admissions occurred within 30 days of GES placement. After GES placement, the median number of gastroparesis-related admissions decreased from 3 to 2 ( p = .002), and the median length of stay (LOS) dropped from 12.5 days to 7.5 days ( p = .004). The median LOS for GES placement was 1.0 days [1.0, 3.8]. Conclusions: GES placement significantly reduced the number of gastroparesis-related admissions and the overall length of stay in hospitalized GpS patients. Our GLM analysis revealed that each additional day of hospitalization slightly decreased the odds of experiencing GpS-related symptoms. These findings suggest that GES can reduce hospital burden and improve quality of life in GpS patients. Further research into strategies for minimizing hospital admissions for severe gastroparesis flares, including bioelectric interventions, is recommended.