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

ACG Clinical Guideline: Gastroparesis

Gastroparesis is characterized by symptoms suggesting retention of food in the stomach with objective evidence of delayed gastric emptying in the absence of mechanical obstruction in the gastric outflow. This condition is increasingly encountered in clinical practice. These guidelines summarize perspectives on the risk factors, diagnosis, and management of gastroparesis in adults (including dietary, pharmacological, device, and interventions directed at the pylorus), and they represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation process. When the evidence was not appropriate for Grading of Recommendations, Assessment, Development, and Evaluation, we used expert consensus to develop key concept statements. These guidelines should be considered as preferred but are not the only approaches to these conditions.

Gastroparesis Symptoms Associated with Intestinal Hypomotility: An Explorative Study Using Wireless Motility Capsule

Objective

Gastric emptying measurements are mandatory in gastroparesis diagnostics, but the association between delayed emptying and symptoms is questionable. It is imperative to find biomarkers better correlated to symptom generation. Hence, we examined the association between symptom severity and gastrointestinal motility measured by wireless motility capsule.

Patients and Methods

In this prospective single-centre study, patients with gastroparesis symptoms were simultaneously investigated with gastric emptying scintigraphy and wireless motility capsule, measuring regional transit times and contractility parameters. Symptom severity was assessed with the Patient Assessment of Upper Gastrointestinal Symptom Severity Index (PAGI-SYM), including the Gastroparesis Cardinal Symptom Index (GCSI).

Results

We included 107 patients (70% women). In the whole patient group, nausea correlated with the gastric (r_s = −0.31, p = 0.007), small bowel (r_s = −0.41, p < 0.001) and colonic (r_s = −0.33, p = 0.012) motility indices. In patients with idiopathic etiology, nausea correlated with small bowel motility index (r_s = −0.81, p < 0.001) and mean stomach pressure (r_s = −0.64, p = 0.013). We also found negative correlations between total GCSI score and maximum pressure of the small bowel (r_s = −0.77, p < 0.001) and colon (r_s = −0.74, p = 0.002). In diabetes patients, total PAGI-SYM score correlated with colonic motility index (r_s = −0.34, p = 0.012), and mean pressure of the colon correlated with upper abdominal pain (r_s = −0.37, p = 0.007). We found no association between symptoms, gastric emptying nor any other transit times.

Conclusion

In patients with gastroparesis symptoms, we found that symptom severity was associated with intestinal hypomotility. Based on these results, gastroparesis diagnostics should also include an evaluation of the small bowel and colon.

Preoperative Blood Glucose Level Predicts Postsurgical Gastroparesis Syndrome after Subtotal Gastrectomy: Development of an Individualized Usable Nomogram

BACKGROUND

Postsurgical gastroparesis syndrome (PGS) after subtotal gastrectomy imposes significant social and economic burdens. We aimed to investigate the relationship between preoperative blood glucose level and PGS and develop a nomogram for individualized prediction. Patients and Methods. We retrospectively analyzed 633 patients with gastric cancer who underwent subtotal gastrectomy. Preoperative blood glucose levels were evaluated via receiver operating characteristic (ROC) curve analysis. Chi-squared tests and multivariable logistic regression analyses were used to develop a predictive model for PGS, presented as a nomogram, which was assessed for its clinical usefulness.

RESULTS

Thirty-eight of 633 patients were diagnosed with PGS. Based on the ROC curve analysis, the preoperative blood glucose cutoff value for PGS was 6.25 mmol/L. The predictors of PGS included preoperative hyperglycemia (odds ratio (OR) 2.3, P = 0.03), body mass index (BMI; OR 0.21, P = 0.14 for BMI < 18.5 and OR 3.0, P = 0.004 for BMI > 24), and the anastomotic method (OR 7.3, P = 0.001 for Billroth II and OR 5.9, P = 0.15 for Roux-en-Y). The predictive model showed good discrimination ability, with a C-index of 0.710, and was clinically useful.

CONCLUSIONS

Preoperative hyperglycemia effectively predicts PGS. We present a nomogram incorporating the preoperative blood glucose level, BMI, anastomotic method, and tumor size, for individualized prediction of PGS.

Evaluation of gastric motility in nine dogs before and after prophylactic laparoscopic gastropexy: a pilot study

BACKGROUND

The purpose of this study was to evaluate the effect of a prophylactic laparoscopic gastropexy on gastric motility in healthy large-breed dogs.

METHODS

This was a prospective pilot study with nine healthy client-owned dogs. Each dog was its own control. Gastric motility was evaluated before and after laparoscopic gastropexy. Dogs were fed a standard diet three weeks before and after surgery. Gastric motility was measured before and 3 weeks after surgery. A wireless motility capsule (WMC) was used to measure gastric pH, intragastric pressure, temperature, frequency of contractions, motility index (MI) and transit time. Non-parametric statistical analysis was used to compare the paired data. Clients were contacted for follow-up information 2 years postoperatively.

RESULTS

Median frequency of gastric contractions was 1.3 (range, 0.6-1.9 contractions/min) before gastropexy and 1.0 (range, 0.3-2.6 contractions/min) after gastropexy (P = 0.820). Median MI was 49.2 (range, 23.7-96.6) before gastropexy and 28.1 (range, 12.2-148.9) after gastropexy (P = 0.652). Median gastric emptying time was 1140 (range, 486-1230 min) before gastropexy and 1110 (range, 306-2610 min) after gastropexy (P = 0.570). During the hour before the WMC passed through the pylorus, median MI was 72.2 (range, 48.2-549.3) before gastropexy and 52.9 (range, 15.20-322.8) after gastropexy (P = 0.734), and frequency of contractions was 1.1 (range, 0.9-4.1 contractions/min) before gastropexy and 1.2 (range, 0.5-3.0 contractions/min) after gastropexy (P = 0.652).

CONCLUSION

Motility in the stomach did not change in healthy dogs after prophylactic laparoscopic gastropexy. We conclude that preventive laparoscopic gastropexy does not induce gastroparesis.

Pathophysiology of idiopathic gastroparesis and implications for therapy

OBJECTIVES

Idiopathic gastroparesis is a gastric motility disorder characterized by chronic upper gastrointestinal symptoms and delayed gastric emptying without an identifiable underlying condition. This review summarizes recent understanding of the pathophysiology and treatment of idiopathic gastroparesis.

MATERIALS AND METHODS

Structured literature search in the PubMed, Embase and ClinicalTrials.gov databases.

RESULTS

Idiopathic gastroparesis involves several alterations in gastric motility and sensation, including delayed gastric emptying, altered myoelectrical activity, impaired fundic accommodation, visceral hypersensitivity and disturbances in antropyloroduodenal motility and coordination. Multiple cellular changes have been identified, including depletion of interstitial cells of Cajal (ICC) and enteric nerves, as well as stromal fibrosis. The underlying cause of these changes is not fully understood but may be an immune imbalance, including loss of anti-inflammatory heme-oxygenase-1 positive (HO-1) macrophages. There is currently no causal therapy for idiopathic gastroparesis. The treatment ladder consists of dietary measures, prokinetic and antiemetic medications, and varying surgical or endoscopic interventions, including promising pyloric therapies. There are ongoing trials with several novel medications, raising hopes for future treatment.

CONCLUSIONS

Patients with idiopathic gastroparesis present several pathophysiological alterations in the stomach, where depletion of ICC is of special importance. Treatment is currently focused on alleviating symptoms through dietary adjustments, medication or surgical or endoscopic interventions.

Small bowel fed response as measured by wireless motility capsule: Comparative analysis in healthy, gastroparetic, and constipated subjects

BACKGROUND

Small bowel fed response is an increased contractile activity pattern following the ingestion of a meal. Postprandial motility is traditionally evaluated using small bowel manometry. Wireless motility capsule (WMC) is an ingestible wireless capsule that measures pH, temperature, and intraluminal pressure. The primary aim of the study was to assess small bowel fed response captured with the non-invasive WMC. The secondary aim was to compare the fed response patterns between healthy subjects and patients with motility disorders of gastroparesis and constipation.

METHODS

All subjects had 250 cc Ensure^® meal 6 hours after WMC ingestion. Frequency of contractions (Ct), area under the curve (AUC), and motility index (MI) were analyzed during 30 minutes of pre-prandial baseline and 60 minutes postprandially in 20-minute windows.

KEY RESULTS

One hundred and eighty-eight subjects (107 healthy, 23 gastroparetics, 58 constipated) were analyzed. Healthy: Ct, AUC, and MI all increased significantly immediately after meal ingestion (P < .01). Motility parameters peak at 20-40 minutes postmeal. The motor activity decreased at the end of postprandial hour, but was still significantly higher than the fasting baseline (P < .01). Gastroparetics: All motility parameters failed to increase significantly compared to the baseline throughout the entire postprandial hour. Constipated: The fed response was similar to healthy subjects.

CONCLUSIONS AND INFERENCES

The small bowel fed response was readily observed in healthy and chronic constipation subjects with WMC but is blunted in gastroparetics. A blunted small bowel fed response suggests neuropathic changes outside the stomach and may contribute to postprandial symptoms.

Disorders of gastrointestinal hypomotility

Ingestion and digestion of food as well as expulsion of residual material from our gastrointestinal tract requires normal propulsive, i.e. motor, function. Hypomotility refers to inherited or acquired changes that come with decreased contractile forces or slower transit. It not only often causes symptoms but also may compromise nutritional status or lead to other complications. While severe forms, such as pseudo-obstruction or ileus, may have a tremendous functional impact, the less severe forms of hypomotility may well be more relevant, as they contribute to common disorders, such as functional dyspepsia, gastroparesis, chronic constipation, and irritable bowel syndrome (IBS). Clinical testing can identify changes in contractile activity, defined by lower amplitudes or abnormal patterns, and the related effects on transit. However, such biomarkers show a limited correlation with overall symptom severity as experienced by patients. Similarly, targeting hypomotility with pharmacological interventions often alters gut motor function but does not consistently improve symptoms. Novel diagnostic approaches may change this apparent paradox and enable us to obtain more comprehensive information by integrating data on electrical activity, mechanical forces, patterns, wall stiffness, and motions with information of the flow of luminal contents. New drugs with more selective effects or more specific delivery may improve benefits and limit adverse effects. Lastly, the complex regulation of gastrointestinal motility involves the brain-gut axis as a reciprocal pathway for afferent and efferent signaling. Considering the role of visceral input in emotion and the effects of emotion on visceral activity, understanding and managing hypomotility disorders requires an integrative approach based on the mind-body continuum or biopsychosocial model of diseases.

Duodenal rather than antral motility contractile parameters correlate with symptom severity in gastroparesis patients

BACKGROUND

Studies of symptomatic gastroparetics consistently find poor correlation with gastric emptying. We hypothesized that concomitant small bowel dysmotility may play a role in symptom causation in gastroparesis and sought to test this hypothesis by using wireless motility capsule (WMC) testing to simultaneously measure antral and duodenal area under pressure curve (AUC) in patients with delayed gastric emptying.

METHODS

Using a cohort from a multicenter clinical trial and a separate tertiary clinical database, we identified gastroparetics that underwent concurrent WMC testing and completed the Gastroparesis Cardinal Symptom Index, a validated questionnaire. Our study included 35 gastroparetics defined by a gastric emptying time (GET) ≥ 5 h. Antral and duodenal AUC were assessed at 1-h windows pre-GET and post-GET, respectively.

KEY RESULTS

We found moderate correlations between duodenal AUC and symptom severity in the combined cohort (n = 35; R = -0.42; p = 0.01; 95% CI -0.7, -0.1). Removing patients with colonic delay resulted in a stronger correlation of duodenal AUC to symptom severity (n = 21; R = -0.63; p < 0.01; 95% CI -0.81, -0.31). The multicenter trial (n = 20) and clinical practice cohorts (n = 15) had significantly different symptom severity and exclusion criteria. When analyzed separately, significant correlations between duodenal AUC and symptom severity were observed (R = -0.71; p < 0.01; 95% CI -0.9, -0.4 and R = -0.72; p < 0.01; 95% CI -0.9, -0.3, respectively). Symptom severity and antral motility showed no correlation.

CONCLUSIONS & INFERENCES

We found significant correlations between duodenal AUC and symptom severity in two cohorts of gastroparetics. Small bowel motility may contribute to symptom generation in gastroparetic patients and this may inform therapeutic considerations.

The use of SmartPill for gastric monitoring

Testing to define delayed gastric emptying is required to diagnose gastroparesis; rapid emptying is found in other patients. Commonly performed methods of gastric emptying testing include scintigraphy and breath testing. The SmartPill wireless motility capsule (WMC) system is US FDA-approved for evaluating suspected delayed emptying in gastroparesis and functional dyspepsia. The device measures transit in the stomach, small intestine, and colon by detecting characteristic pH transitions; and quantifies pressure waves in each gut region. WMC gastric emptying times correlate with scintigraphic measures. Incremental benefits of WMC testing in patients with suspected gastroparesis include delineation of pressure abnormalities and small intestinal and colonic transit delays. Acceptance of trial data confirming usefulness of WMC testing in suspected gastric motor disorders has been hampered by small sample sizes and design limitations. Ongoing multicenter studies will validate the utility of WMC methods in patients with suspected gastroparesis and other upper gastrointestinal motor disorders.

Gastrointestinal complications of diabetes mellitus

Diabetes mellitus affects virtually every organ system in the body and the degree of organ involvement depends on the duration and severity of the disease, and other co-morbidities. Gastrointestinal (GI) involvement can present with esophageal dysmotility, gastro-esophageal reflux disease (GERD), gastroparesis, enteropathy, non alcoholic fatty liver disease (NAFLD) and glycogenic hepatopathy. Severity of GERD is inversely related to glycemic control and management is with prokinetics and proton pump inhibitors. Diabetic gastroparesis manifests as early satiety, bloating, vomiting, abdominal pain and erratic glycemic control. Gastric emptying scintigraphy is considered the gold standard test for diagnosis. Management includes dietary modifications, maintaining euglycemia, prokinetics, endoscopic and surgical treatments. Diabetic enteropathy is also common and management involves glycemic control and symptomatic measures. NAFLD is considered a hepatic manifestation of metabolic syndrome and treatment is mainly lifestyle measures, with diabetes and dyslipidemia management when coexistent. Glycogenic hepatopathy is a manifestation of poorly controlled type 1 diabetes and is managed by prompt insulin treatment. Though GI complications of diabetes are relatively common, awareness about its manifestations and treatment options are low among physicians. Optimal management of GI complications is important for appropriate metabolic control of diabetes and improvement in quality of life of the patient. This review is an update on the GI complications of diabetes, their pathophysiology, diagnostic evaluation and management.