Gastroduodenal mechanisms underlying functional gastric disorders

Frequency-Specific Effects of Noninvasive Median Nerve Stimulation on Gastric Slow Wave Activity in Humans

OBJECTIVES

The present study explored the effects of different frequencies of noninvasive median nerve stimulation (nMNS) on two autonomic responses: gastric slow waves under water-loading condition and heart rate variability (HRV). To the best of our knowledge, this is the first study to document the effects of different frequencies of nMNS on gastric slow waves (GSW) in humans under 5-minute water-loading condition.

MATERIALS AND METHODS

Twenty healthy adult participants were fitted with a noninvasive body-surface gastric mapping, electrocardiogram (ECG), and a transcutaneous electrical nerve stimulation device and administered with four different nMNS frequencies (placebo-0 Hz, 40 Hz, 120 Hz, and 200 Hz) on four separate counterbalanced days. After the baseline and stimulation periods, a 5-minute water-load test was applied, and a post-water-load period also is recorded for ECG and GSW activity. Time-domain HRV parameters are analyzed with repeated-measures one-way analysis of variance (ANOVA) and a post hoc Tukey multiple comparison test. Parameters that failed normality tests underwent a Freidman test with a post hoc Dunn multiple comparison test. GSW data are analyzed with repeated-measures mixed-effects ANOVA.

RESULTS

In empty stomach (baseline vs stimulation), only the 40-Hz frequency statistically significantly (p = 0.0129) increased GSW amplitude in comparison with its own baseline. In full (distended) stomach, 40-Hz and 200-Hz stimulations showed a statistically significant difference (post hoc multiple comparison adjusted, p = 0.0016 and p = 0.0183, respectively) in the Gastric Rhythm Index in comparison with the change obtained by placebo stimulation (baseline vs poststimulation periods); 120-Hz nMNS showed a statistically significant difference (p = 0.0300) in the stress index in comparison with the decrease observed in the placebo group. However, 120-Hz nMNS did not induce a statistically significant change in gastric electrical activity compared to placebo stimulation. The nMNS did not follow the linear "dose-response" relationship between nMNS frequency and gastric/HRV parameters.

CONCLUSIONS

The 40-Hz and 200-Hz nMNS frequencies showed the most promising results in response to gastric distension, in addition to 40 Hz for an empty stomach. Further research is essential to explore the potential therapeutic effects of these frequencies on gastric diseases such as gastroparesis, gastroesophageal reflux disease, and functional dyspepsia that can be used in wrist wearables.

Dietary therapy of the herbal porridge improves the symptoms of functional dyspepsia: A randomized, double-blind, placebo-controlled, clinical trial

This study (ISRCTN17174559) aimed to explore the efficacy and safety of a kind of herbal porridge (Hou Gu Mi Xi) on the clinical symptoms of functional dyspepsia (FD). This was a single-center, single-dose, prospective, double-blind, randomized controlled trial involving 64 participants with FD (35 cases and 29 controls) for 2 months of intervention and 1 month of follow-up. The 7-point Global Overall Symptom Scale (GOSS), 36-Item Short Form Survey (SF-36), and other indicators were assessed at baseline (day 0), at days 15, 30, and 60 of treatment, and at follow-up 1 month after the end of the intervention. Many participants with FD achieved remission of their epigastric symptoms at follow-up on the 90th day after treatment with herbal porridge compared to the placebo group (45.71% vs. 20.69%, p = .036). Furthermore, herbal porridge appeared to be effective in improving the quality of life of participants with FD, which was reflected in the rising SF-36 scores for physical role, bodily pain, emotional role, and mental health. Although adverse events were reported, there was no overall difference in the number of adverse events between the two groups (p = .578). Herbal porridge is another effective and safe method for improving the symptoms and quality of life in patients with FD.

Research Progress for Probiotics Regulating Intestinal Flora to Improve Functional Dyspepsia: A Review

Functional dyspepsia (FD) is a common functional gastrointestinal disorder. The pathophysiology remains poorly understood; however, alterations in the small intestinal microbiome have been observed. Current treatments for FD with drugs are limited, and there are certain safety problems. A class of active probiotic bacteria can control gastrointestinal homeostasis, nutritional digestion and absorption, and the energy balance when taken in certain dosages. Probiotics play many roles in maintaining intestinal microecological balance, improving the intestinal barrier function, and regulating the immune response. The presence and composition of intestinal microorganisms play a vital role in the onset and progression of FD and serve as a critical factor for both regulation and potential intervention regarding the management of this condition. Thus, there are potential advantages to alleviating FD by regulating the intestinal flora using probiotics, targeting intestinal microorganisms. This review summarizes the research progress of probiotics regarding improving FD by regulating intestinal flora and provides a reference basis for probiotics to improve FD.

Eosinophil and mast cell-derived exosomes promote integrity of intestinal mucosa via the NEAT1/miR-211-5p/glial cell line-derived neurotrophic factor axis in duodenum

BACKGROUND

Exosomes are applied as biomarkers in several diseases according to their disease-specific profiles. However, the exosomes effects in functional dyspepsia (FD) are still fragmentary. Here we examined the role of Eosinophil and mast cell derived-exosomes in FD progression.

METHODS

Fifty FD subjects and age- and sex-matched healthy controls were included in this retrospective cohort study. Duodenal mucosa and gastric juice were collected to analyze molecular difference. Eosinophil and mast cell were evaluated by immunofluorescence and microarray was subjected to examine the expression levels of NEAT1, miR-211-5p, and glial cell line-derived neurotrophic factor (GDNF), which were subsequently were tested by quantitative reverse transcription PCR (RT-qPCR) validation cohorts. CCK-8 assays, and wound healing assays were used to evaluate integrity of intestinal mucosal barrier in vitro. Rats' weights and gastric emptying rates were used as evaluation of FD severity in vivo.

RESULTS

Eosinophil and mast cell were enriched and secreted more exosomes in duodenal mucosa of FD patients. We identified differential lncRNAs that were consistently and significantly up regulated in FD cases. Of these, NEAT1 was further validated by RT-qPCR and had closely relationship with GDNF. MiR-211-5p level was found to be reduced in FD and negatively related with NEAT1 and GDNF. Furthermore, NEAT1and GDNF relived FD while miR-211-5p made symptoms worse. The NEAT1/miR-211-5p/GDNF axis had a good predictive ability for FD.

CONCLUSIONS

The NEAT1/miR-211-5p/GDNF could be a potential FD biomarker.

Review article: Functional dyspepsia and pregnancy-Effects and management in a special population

BACKGROUND

Around 10% of Americans meet the Rome IV criteria for functional dyspepsia (FD), with a significantly higher rate in women. FD also has a higher prevalence in women below the age of 50, suggesting that women who are affected are likely to be of reproductive age. Unfortunately, there is a lack of research or evidence-based guidelines on managing FD in pregnancy.

AIMS AND METHODS

To address this issue, we aimed to perform a systematic review of the interactions between FD and pregnancy and managing pre-existing FD in the peripartum and post-partum phases using current lifestyle, pharmacological, non-pharmacological and alternative medicine interventions.

RESULTS

Due to the lack of Rome IV FD-specific data in pregnancy, we instead performed a narrative review on how existing FD interventions could be extrapolated to the pregnant population. Where possible we use the highest level of available evidence or official guidelines to answer these questions, which often involves synthesising treatment and safety evidence of these interventions in other diseases during pregnancy. Finally, we highlight current substantial knowledge gaps requiring further research for the safe management of a pregnant patient with pre-existing FD.

CONCLUSIONS

Overall, despite the paucity of knowledge of treating FD during pregnancy, providers can mitigate this uncertainty by planning ahead with the patient. Patients should ideally minimise treatment until after breastfeeding. However, interdisciplinary resources are available to ensure that minimal-risk interventions are maximised, while interventions with more risks, if necessary, are justifiable by both the patient and the care team. Future investigations should continue to elicit the mechanistic relationship between FD and pregnancy while cautiously expanding prospective research on promising and safe therapies in pregnant patients with pre-existing FD.

A survey of functional dyspepsia in 361,360 individuals: Phenotypic and genetic cross-disease analyses

BACKGROUND

Functional dyspepsia (FD) is a common gastrointestinal condition of poorly understood pathophysiology. While symptoms' overlap with other conditions may indicate common pathogenetic mechanisms, genetic predisposition is suspected but has not been adequately investigated.

METHODS

Using healthcare, questionnaire, and genetic data from three large population-based biobanks (UK Biobank, EGCUT, and MGI), we surveyed FD comorbidities, heritability, and genetic correlations across a wide spectrum of conditions and traits in 10,078 cases and 351,282 non-FD controls of European ancestry.

KEY RESULTS

In UK Biobank, 281 diagnoses were detected at increased prevalence in FD, based on healthcare records. Among these, gastrointestinal conditions (OR = 4.0, p < 1.0 × 10^-300 ), anxiety disorders (OR = 2.3, p < 1.4 × 10^-27 ), ischemic heart disease (OR = 2.2, p < 2.3 × 10^-76 ), and infectious and parasitic diseases (OR = 2.1, p = 1.5 × 10^-73 ) showed strongest association with FD. Similar results were obtained in an analysis of self-reported conditions and use of medications from questionnaire data. Based on a genome-wide association meta-analysis of genotypes across all cohorts, FD heritability was estimated close to 5% ( hSNP2  = 0.047, p = 0.014). Genetic correlations indicate FD predisposition is shared with several other diseases and traits (r_g  > 0.344), mostly overlapping with those also enriched in FD patients. Suggestive (p < 5.0 × 10^-6 ) association with FD risk was detected for 13 loci, with 2 showing nominal replication (p < 0.05) in an independent cohort of 192 FD patients.

CONCLUSIONS & INFERENCES

FD has a weak heritable component that shows commonalities with multiple conditions across a wide spectrum of pathophysiological domains. This new knowledge contributes to a better understanding of FD etiology and may have implications for improving its treatment.

Aqueous Extract of Phyllanthus emblica L. Alleviates Functional Dyspepsia through Regulating Gastrointestinal Hormones and Gut Microbiome In Vivo

Phyllanthus emblica L. fruits were extracted by a hot water assistant with ultrasonication to obtain aqueous Phyllanthus emblica L. extract (APE). The ameliorating functional dyspepsia (FD) effect of a low dose (150 mg/kg) and a high dose (300 mg/kg) of APE was exhibited by determining the gastrointestinal motility, gastrointestinal hormones, and gut microbiome shifts in reserpine induced FD male balb/c mice. APE increased the gastrointestinal motility including the gastric emptying (GE) rate and small intestinal transit (SIT) rate. The level of serum gastrointestinal hormones such as motilin (MTL) and gastrin (GAS) increased, and the vasoactive intestinal peptide (VIP) level decreased after the administration of APE. Furthermore, the gut microbiome analysis demonstrated that APE could regulate the microbiome structure and restore homeostasis by elevating useful bacterial abundance, while simultaneously decreasing harmful bacterial abundance. This study demonstrated the ameliorating FD effect of APE and its potential efficacy in curing functional gastrointestinal disorders and maintaining a healthy digestive tract.

Role of Neuromodulators for the Management of Post-Gastric-Fundoplication Dyspepsia: A Retrospective Series

Post-fundoplication dyspepsia is a common complication of gastric fundoplication surgeries. This can be attributable to the loss of fundal relaxation, decreased gastric accommodation, and/or alterations in gastric motility and sensitivity following fundoplication. The role of neuromodulators in the management of such symptoms is unknown. We retrospectively assessed the efficacy of neuromodulators such as tricyclic antidepressants, buspirone, and mirtazapine for the management of post-fundoplication dyspepsia.

United European Gastroenterology (UEG) and European Society for Neurogastroenterology and Motility (ESNM) consensus on functional dyspepsia

BACKGROUND

Functional dyspepsia (FD) is one of the most common conditions in clinical practice. In spite of its prevalence, FD is associated with major uncertainties in terms of its definition, underlying pathophysiology, diagnosis, treatment, and prognosis.

METHODS

A Delphi consensus was initiated with 41 experts from 22 European countries who conducted a literature summary and voting process on 87 statements. Quality of evidence was evaluated using the grading of recommendations, assessment, development, and evaluation (GRADE) criteria. Consensus (defined as >80% agreement) was reached for 36 statements.

RESULTS

The panel agreed with the definition in terms of its cardinal symptoms (early satiation, postprandial fullness, epigastric pain, and epigastric burning), its subdivision into epigastric pain syndrome and postprandial distress syndrome, and the presence of accessory symptoms (upper abdominal bloating, nausea, belching), and overlapping conditions. Also, well accepted are the female predominance of FD, its impact on quality of life and health costs, and acute gastrointestinal infections, and anxiety as risk factors. In terms of pathophysiological mechanisms, the consensus supports a role for impaired gastric accommodation, delayed gastric emptying, hypersensitivity to gastric distention, Helicobacter pylori infection, and altered central processing of signals from the gastroduodenal region. There is consensus that endoscopy is mandatory for establishing a firm diagnosis of FD, but that in primary care, patients without alarm symptoms or risk factors can be managed without endoscopy. There is consensus that H. pylori status should be determined in every patient with dyspeptic symptoms and H. pylori positive patients should receive eradication therapy. Also, proton pump inhibitor therapy is considered an effective therapy for FD, but no other treatment approach reached a consensus. The long-term prognosis and life expectancy are favorable.

CONCLUSIONS AND INFERENCES

A multinational group of European experts summarized the current state of consensus on the definition, diagnosis and management of FD.

The effect of prucalopride on gastric sensorimotor function and satiation in healthy volunteers

BACKGROUND

Gastric motor function alterations have been implicated in the pathogenesis of functional dyspepsia with postprandial distress syndrome (PDS). Prucalopride, a 5-TH4 agonist, is known to stimulate gastrointestinal motility. We aimed to evaluate the effect of prucalopride on gastric sensorimotor function in healthy subjects (HV).

METHODS

Barostat and intragastric pressure (IGP) measurements were performed in 17 HV (59% females, age 29.4 ± 2.7 y) after treatment with placebo or prucalopride (2 mg) (single-blind cross-over). Isobaric stepwise distensions and gastric sensations were assessed to determine gastric compliance and sensitivity. Gastric accommodation (GA) with the barostat was quantified before and after ingestion of 200 ml of a nutrient drink (ND). GA measured by IGP was quantified as the drop of IGP from baseline during the intragastric infusion of ND until maximal satiation (60 ml/min).

KEY RESULTS

Prucalopride did not affect barostat assessed gastric compliance or sensitivity. No differences were observed in GA after prucalopride. During the barostat study, 10 min after the meal, 7 HVs reported significantly higher ratings for nausea after prucalopride (p < 0.001), and vomiting was induced in 4 of the HVs. A positive correlation was observed between the delta mean perception of nausea with the delta mean increase of intra-balloon volume before and after meal ingestion (r = 0.37, p = 0.03). During IGP measurements, no effect on nutrient tolerance was observed and increased cramp severity scores were observed which were associated with a significant increase of distal IGP (r = 0.78, p < 0.0001).

CONCLUSIONS & INFERENCES

Prucalopride does not enhances gastric accommodation but it might increase sensitivity to gastric distention. Furthermore, the increase in sensitivity seems to be related to an increase in nausea with distension. Clinicaltrials.gov: NCT04429802.

An Herbal Formulation of Jiawei Xiaoyao for the Treatment of Functional Dyspepsia: A Multicenter, Randomized, Placebo-Controlled, Clinical Trial

To investigate the efficacy and safety of an herbal formulation of Jiawei Xiaoyao (JX) on gastrointestinal symptoms in patients with functional dyspepsia (FD) who had previously rejected standard therapies of proton pump inhibitors, H2 blockers, or Helicobacter pylori eradication.

Functional Dyspepsia: Diagnostic and Therapeutic Approaches

Functional dyspepsia is a common functional gastrointestinal (GI) disorder of gastroduodenal origin, diagnosed clinically in the presence of prototypical symptoms of epigastric pain and meal-related symptoms, and without structural explanation. The most recent diagnostic criteria provide for two functional dyspepsia subtypes, epigastric pain syndrome (EPS) and post-prandial distress syndrome (PDS) based on the predominant symptom pattern. The evaluation of dyspepsia should keep laboratory, imaging, and invasive testing to a minimum, as extensive or repetitive investigations are of rather low diagnostic yield in the absence of localizing symptoms or alarm features. Factors with etiopathologic relationships to functional dyspepsia include micro-inflammation, GI infections, abnormalities of gastroduodenal motility, visceral hypersensitivity, disturbances along the brain-gut axis, and psychological factors; all of these causative mechanisms have potential to partially explain symptoms in some functional dyspepsia patients, thus providing a rationale for the efficacy of a diversity of therapeutic approaches to functional dyspepsia. Management of dyspepsia symptoms relies upon both pharmacologic treatments and non-pharmacologic approaches, including psychological and complementary interventions. The evidence in support of established functional dyspepsia therapies is reviewed, and forms the basis for an effective functional dyspepsia treatment strategy emphasizing the patient's current symptom severity, pattern, and impact on the function and quality of life of the individual.

United European Gastroenterology (UEG) and European Society for Neurogastroenterology and Motility (ESNM) consensus on functional dyspepsia

Background

Functional dyspepsia (FD) is one of the most common conditions in clinical practice. In spite of its prevalence, FD is associated with major uncertainties in terms of its definition, underlying pathophysiology, diagnosis, treatment, and prognosis.

Methods

A Delphi consensus was initiated with 41 experts from 22 European countries who conducted a literature summary and voting process on 87 statements. Quality of evidence was evaluated using the grading of recommendations, assessment, development, and evaluation (GRADE) criteria. Consensus (defined as >80% agreement) was reached for 36 statements.

Results

The panel agreed with the definition in terms of its cardinal symptoms (early satiation, postprandial fullness, epigastric pain, and epigastric burning), its subdivision into epigastric pain syndrome and postprandial distress syndrome, and the presence of accessory symptoms (upper abdominal bloating, nausea, belching), and overlapping conditions. Also, well accepted are the female predominance of FD, its impact on quality of life and health costs, and acute gastrointestinal infections, and anxiety as risk factors. In terms of pathophysiological mechanisms, the consensus supports a role for impaired gastric accommodation, delayed gastric emptying, hypersensitivity to gastric distention, Helicobacter pylori infection, and altered central processing of signals from the gastroduodenal region. There is consensus that endoscopy is mandatory for establishing a firm diagnosis of FD, but that in primary care, patients without alarm symptoms or risk factors can be managed without endoscopy. There is consensus that H. pylori status should be determined in every patient with dyspeptic symptoms and H. pylori positive patients should receive eradication therapy. Also, proton pump inhibitor therapy is considered an effective therapy for FD, but no other treatment approach reached a consensus. The long‐term prognosis and life expectancy are favorable.

Conclusions and Inferences

A multinational group of European experts summarized the current state of consensus on the definition, diagnosis and management of FD.

Current knowledge

Functional dyspepsia is one of the most common conditions encountered in clinical practice.

There is a lack of guidance for clinicians in guiding diagnosis and treatment of this prevalent condition.

No treatments are currently approved for the treatment of functional dyspepsia in Europe.

What is new here

A Delphi panel consisting of 41 experts from 22 European countries established the level of consensus on 87 statements regarding functional dyspepsia.

The statements reaching consensus serve to guide clinicians in recognizing, diagnosing and treating FD in clinical practice.

Endoscopy is mandatory for establishing a firm diagnosis of functional dyspepsia D, but in primary care patients without alarm symptoms or risk factors can be managed without endoscopy.

Helicobacter pylori status should be determined in every patient with dyspeptic symptoms and H. Pylori positive patients should receive eradication therapy.

Proton pump inhibitor‐therapy is considered an effective therapy for FD, but no other treatment approach reached consensus support.

Persian Herbal Medicine in Functional Dyspepsia: A Systematic Review

INTRODUCTION

According to Rome IV, functional dyspepsia is diagnosed with the presence of dyspepsia in the absence of organic or metabolic causes. FD caused by several factors, such as impaired gastric accommodation and hypersensitivity to gastric distention. Several studies have reported the effectiveness of herbal medicine on FD. This article, thus, reviews Persian herbal medicine in FD.

METHODS

Electronic databases, including Pubmed, Scopus, Cochrane, Embase, Web of science and Ovid, were searched so as to find clinical articles related to dyspepsia and herbal medicine by July 2019. Our search strategies were traditional medicine, complementary and alternative medicine, herb, plant, and dyspepsia. We excluded all articles except Persian clinical trials.

RESULTS

We found 34 clinical trials with 15 herbs and 4 compound herbal remedies like Asparagus racemosus, Brassica oleracea, Cynara scolymus, Ocimum basilicum, Mentha longifolia, Mentha pulegium, Mentha piperata, Pimpinella anisum, Nigella sativa, Mastic gum, Curcuma longa, Pistatio Atlantica, Glycyrrhiza glabra, Solanum tuberosum and Zingiber officinale and compound remedies of Rosa damascene & Crocus sativus, Trachyspermum copticom & Apium graveolence, Carum carvi & Mentha pipperata, Gingiber officinalis & Cynara scolymus are effective in functional dyspepsia.

CONCLUSION

Many people use herbal and traditional remedies for the treatment of disorders such as gastrointestinal disorders, especially in Asian countries. Several studies reported the efficacy of herbal medicine in functional dyspepsia. Although their mechanisms are not fully understood, it seems they can modulate GI motility and improve symptoms of FD.

Paradigm Shift: Functional Dyspepsia-A "Leaky Gut" Disorder?

For up to 2 decades, pathophysiological research in functional dyspepsia focused on gastric sensorimotor dysfunction underlying symptom generation. Recent pathophysiological research has focused on low-grade inflammation in the duodenal mucosa. Emerging evidence confirms a loss of mucosal integrity in the duodenum in functional dyspepsia, and this is confirmed in a confocal laser endomicroscopy study demonstrating altered mucosal barrier function and pyroptosis. This technique may help to establish underlying mechanisms and evaluate novel therapeutic approaches to functional dyspepsia.

Gastric Motor Functions in Patients With Mood Disorders and Functional Gastroduodenal Symptoms

OBJECTIVE

Functional gastroduodenal symptoms (FGDSs) may result from perturbations in gastric emptying (GE) and gastric accommodation (GA), which are variably affected by acute stress. This study aimed to examine whether individuals who have both mood disorder and FGDS exhibit differences in GE and GA using standardized, validated, and reproducible noninvasive methods.

METHODS

Using a data retrieval program, 1554 individuals at a single center were identified after having undergone measurements of GE by scintigraphy of a 99mTc-radiolabeled egg (320 kcal, 30% fat meal) and GA by single-photon emission computed tomography to assess the underlying pathophysiology in FGDS. An extensive medical record review identified 267 of these individuals as having diagnoses of depression, anxiety, or comorbid anxiety/depression (CAD). Differences in GE and GA as related to the presence of anxiety or depressive disorders were analyzed using one-way analysis of variance on ranks and Mann-Whitney tests for the two-group comparisons.

RESULTS

Sixty-three patients with anxiety, 134 with depression, and 70 with CAD were identified. GE at 1 hour was slower (p = .04) and GE at 2 hours numerically decreased (p = .07) for depression compared with anxiety. GA was diminished for CAD compared with anxiety (p = .04) and depression (p = .009). There were no differences in fasting gastric volume or GE at 4 hours.

CONCLUSIONS

In this study examining GE and GA in anxiety and depressive disorders among patients with FGDS, the combined presence of anxiety and depression was associated with impaired GA compared with patients with depression or anxiety alone, and early GE seemed to be slower in those with depression compared with patients with anxiety.

Evaluation of main functional dyspepsia symptoms after probiotic administration in patients receiving conventional pharmacological therapies

Objective

Postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS) are the two main forms of functional dyspepsia (FD). Probiotics are a promising therapy for FD, but current data remains heterogeneous. This work aims to evaluate a probiotic combination of Lacticaseibacillus rhamnosus LR04 (DSM 16605), Lactiplantibacillus pentosus LPS01 (DSM 21980), Lactiplantibacillus plantarum LP01 (LMG P-21021), and Lactobacillus delbrueckii subsp. delbruekii LDD01 (DMS 22106), alone or together with other pharmacological therapies, for clinical improvement of symptoms associated with FD.

Methods

Patients with FD were enrolled and divided into two groups: PDS and EPS. Probiotic alone or combined with prokinetics, antacids, or proton-pump-inhibitors were administered for 30 days. A progressive-score scale was used to evaluate symptoms in all patients at the beginning of the trial and at 15 days after the end of treatment.

Results

A cohort of 2676 patients were enrolled (1 357 with PDS; 1 319 with EPS). All patients showed significant improvements in dyspeptic symptoms following treatment. In patients with PDS, probiotic alone resulted in the lowest prevalence of symptoms following treatment, while patients with EPS showed no clear between-treatment differences.

Conclusions

Dyspeptic symptoms were reduced following treatment in all patients.

Electroacupuncture for the treatment of functional dyspepsia: A systematic review and meta-analysis

BACKGROUND

Functional dyspepsia (FD) is a common functional gastrointestinal disease. Acupuncture, including electroacupuncture (EA) is widely used as a complementary and alternative treatment for patients with FD. This study aimed to explore the effectiveness of EA for the treatment of FD.

METHODS

We searched Embase, PubMed, and the Cochrane Central Register of Controlled Trials (Cochrane Library) for randomized controlled trials of FD treated by EA from inception to February 3, 2020. Two reviewers will independently screen studies for data extraction and assess the quality and risk of bias. The Cochrane Collaboration's risk of bias tool, RevMan 5.3 software were used for meta-analysis. Data were pooled to calculate relative risk and 95% confidence intervals (CIs) of substantial improvement after treatment for dichotomous data and mean differences (SMDs) and 95% CIs for continuous data.

RESULTS

Seven randomized clinical trials included 853 patients. This meta-analysis investigated the effectiveness of EA alone in the treatment of FD relative to sham-EA or pharmacologic medication (PM). The results showed that EA could significantly improve clinical symptoms. Compared with sham-EA, EA was more effective in reducing symptom scores (SMD -3.44, 95% CI -4.21 to -2.67) and increasing normal slow waves of electrogastrogram (SMD 0.93, 95% CI -0.30 to1.55). When EA was combined with PM, there was no significant difference in reducing symptom scores (SMD -0.18, 95% CI -0.51 to 0.16), increasing the effective rate of clinical symptoms (risk ratio 1.04, 95% CI 0.96 to 1.13), enhancing the level of plasma motilin (SMD 0.93, 95% CI -0.30 to1.55), and reducing gastric half-emptying time (SMD 0.02, 95% CI -0.16 to 0.20). The results also showed that there were very few adverse events reported.

CONCLUSION

This meta-analysis suggests that EA is better than the placebo (sham-EA) in treating FD, and the therapeutic effect of EA on FD is equivalent to that of PM on FD. Compared with PM, EA for FD is safer and has fewer adverse reactions. Despite limitations due to the quality and number of the included studies, EA might be used as an effective and safe treatment for FD.

Evidence of Duodenal Epithelial Barrier Impairment and Increased Pyroptosis in Patients With Functional Dyspepsia on Confocal Laser Endomicroscopy and "Ex Vivo" Mucosa Analysis

INTRODUCTION

Duodenal epithelial barrier impairment and immune activation may play a role in the pathogenesis of functional dyspepsia (FD). This study was aimed to evaluate the duodenal epithelium of patients with FD and healthy individuals for detectable microscopic structural abnormalities.

METHODS

This is a prospective study using esophagogastroduodenoscopy enhanced with duodenal confocal laser endomicroscopy (CLE) and mucosal biopsies in patients with FD (n = 16) and healthy controls (n = 18). Blinded CLE images analysis evaluated the density of epithelial gaps (cell extrusion zones), a validated endoscopic measure of the intestinal barrier status. Analyses of the biopsied duodenal mucosa included standard histology, quantification of mucosal immune cells/cytokines, and immunohistochemistry for inflammatory epithelial cell death called pyroptosis. Transepithelial electrical resistance (TEER) was measured using Ussing chambers. Epithelial cell-to-cell adhesion proteins expression was assessed by real-time polymerase chain reaction.

RESULTS

Patients with FD had significantly higher epithelial gap density on CLE in the distal duodenum than that of controls (P = 0.002). These mucosal abnormalities corresponded to significant changes in the duodenal biopsy samples of patients with FD, compared with controls, including impaired mucosal integrity by TEER (P = 0.009) and increased number of epithelial cells undergoing pyroptosis (P = 0.04). Reduced TEER inversely correlated with the severity of certain dyspeptic symptoms. Furthermore, patients with FD demonstrated altered duodenal expression of claudin-1 and interleukin-6. No differences in standard histology were found between the groups.

DISCUSSION

This is the first report of duodenal CLE abnormalities in patients with FD, corroborated by biopsy findings of epithelial barrier impairment and increased cell death, implicating that duodenal barrier disruption is a pathogenesis factor in FD and introducing CLE a potential diagnostic biomarker in FD.

Safety and efficacy of Soyo-san for the treatment of functional dyspepsia: A protocol for systematic review and meta-analysis

BACKGROUND

Functional dyspepsia (FD) is a common condition characterized by gastrointestinal symptoms, such as abdominal fullness and epigastric pain. With the limitations of conventional Western medical treatments, symptoms often recur and lead to poor quality of life. Soyo-san (SYS) is a traditional herbal medicine that has been frequently used to treat indigestion. This protocol was designed to investigate the safety and efficacy of SYS for treating FD through a systematic review and meta-analysis.

METHODS

Trials will be searched from the following 11 electronic databases, up to March 2020: EMBASE, Medline (via PubMED), the Cochrane Central Register of Controlled Trials (CENTRAL), Allied and Complementary Medicine Database (AMED), Korean Medical Database (KMbase), KoreaMed, Korean Studies Information Service System (KISS), National Digital Science Library (NDSL), Oriental Medicine Advanced Searching Integrated System (OASIS), China National Knowledge Infrastructure Database (CNKI), and Citation Information by Nii (CiNii). Randomized controlled trials (RCTs) of SYS or modified SYS for FD will be included in this systematic review. The effects of control interventions such as placebo, no-treatment, and conventional Western medicine will be compared with those of SYS. RCTs investigating the synergetic effect of SYS and Western medicine compared with conventional Western medicine alone will also be evaluated. Two investigators will independently extract the data and assess the risk of bias in the included studies. The total clinical effective rate will be measured as the main outcome.

RESULTS

This systematic review will provide data on the use of SYS in the treatment of FD, based on indicators such as dyspepsia-related symptom score, recurrence rate, and adverse events.

CONCLUSION

This study will determine the safety and efficacy of SYS for the treatment of FD. REVIEW REGISTRY UNIQUE IDENTIFYING NUMBER:: reviewregistry969.

Trimebutine Maleate Monotherapy for Functional Dyspepsia: A Multicenter, Randomized, Double-Blind Placebo Controlled Prospective Trial

Background and Objectives: Functional dyspepsia (FD) is one of the most common functional gastrointestinal disorders; it has a great impact on patient quality of life and is difficult to treat satisfactorily. This study evaluates the efficacy and safety of trimebutine maleate (TM) in patients with FD. Materials and Methods: Α multicenter, randomized, double-blind, placebo controlled, prospective study was conducted, including 211 patients with FD. Participants were randomized to receive TM 300 mg twice per day (BID, 108 patients) or placebo BID (103 patients) for 4 weeks. The Glasgow Dyspepsia Severity Score (GDSS) was used to evaluate the relief of dyspepsia symptoms. Moreover, as a pilot secondary endpoint, a substudy (eight participants on TM and eight on placebo) was conducted in to evaluate gastric emptying (GE), estimated using a 99mTc-Tin Colloid Semi Solid Meal Scintigraphy test. Results: Of the 211 patients enrolled, 185 (87.7%) (97 (52.4%) in the TM group and 88 (47.6%) in the placebo group) completed the study and were analyzed. The groups did not differ in their demographic and medical history data. Regarding symptom relief, being the primary endpoint, a statistically significant reduction in GDSS for the TM group was revealed between the first (2-week) and final (4-week) visit (p-value = 0.02). The 99 mTc-Tin Colloid Semi Solid Meal Scintigraphy testing showed that TM significantly accelerated GE obtained at 50 min (median emptying 75.5% in the TM group vs. 66.6% in the placebo group, p = 0.036). Adverse effects of low to moderate severity were reported in 12.3% of the patients on TM. Conclusion: TM monotherapy appears to be an effective and safe approach to treating FD, although the findings presented here warrant further confirmation.

Effects and mechanisms of acupuncture and electroacupuncture for functional dyspepsia: A systematic review

BACKGROUND

Functional dyspepsia (FD) is a common digestive disease with limited therapeutic options. According to evidence-based clinical practice, acupuncture or electroacupuncture (EA) seems to be a promising therapy for patients with FD. However, there is still a lack of systematic reviews that have analyzed current clinical trials for a better understanding of mechanisms involved in the ameliorating effect of acupuncture and EA on FD.

AIM

To evaluate the results and qualities of existing clinical evidence for researching the underlying mechanisms of acupuncture/EA in treating FD.

METHODS

A systematic search of the literature was performed to identify randomized controlled trials in which research on the mechanism of acupuncture or EA was conducted in FD patients. Databases searched included PubMed, EMBASE, Cochrane Library, and Web of Science. Data extraction and quality assessment were completed by two investigators independently and the results of quality evaluation were exported through Review Manager V5.3.

RESULTS

Eight studies were included in this review with a total of 17 items for detecting techniques for mechanistic research. Positive effects of acupuncture and EA were observed in regulating gastric motility, gastric accommodation, mental status, gastrointestinal hormones, and central and autonomic functions while improving dyspeptic symptoms and quality of life.

CONCLUSION

The key findings of this systematic review support the potential of acupuncture and EA in altering the heterogeneous pathophysiology in patients with FD. However, high-quality studies with well-planned designs are necessary to provide more credible evidence.

Gastroparesis: New insights into an old disease

Gastroparesis (Gp) is a chronic disease characterized by a delayed gastric emptying in the absence of mechanical obstruction. Although this condition has been reported in the literature since the mid-1900s, only recently has there been renewed clinical and scientific interest in this disease, which has a potentially great impact on the quality of life. The aim of this review is to explore the pathophysiological, diagnostic and therapeutical aspects of Gp according to the most recent evidence. A comprehensive online search for Gp was carried out using MEDLINE and EMBASE. Gp is the result of neuromuscular abnormalities of the gastric motor function. There is evidence that patients with idiopathic and diabetic Gp may display a reduction in nitrergic inhibitory neurons and in interstitial cells of Cajal and/or telocytes. As regards diagnostic approach, 99-Technetium scintigraphy is currently considered to be the gold standard for Gp. Its limits are a lack of standardization and a mild risk of radiation exposure. The C13 breath testing is a valid and safe alternative method. ¹³C acid octanoic and the ¹³C Spirulina platensis recently approved by the Food and Drug Administration are the most commonly used diagnostic kits. The wireless motility capsule is a promising technique, but its use is limited by costs and scarce availability in many countries. Finally, therapeutic strategies are related to the clinical severity of Gp. In mild and moderate Gp, dietary modification and prokinetic agents are generally sufficient. Metoclopramide is the only drug approved by the Food and Drug Administration for Gp. However, other older and new prokinetics and antiemetics can be considered. As a second-line therapy, tricyclic antidepressants and cannabinoids have been proposed. In severe cases the normal nutritional approach can be compromised and artificial nutrition may be needed. In drug-unresponsive Gp patients some alternative strategies (endoscopic, electric stimulation or surgery) are available.

The Effects of Low-Dose and High-Dose Decoctions of Fructus aurantii in a Rat Model of Functional Dyspepsia

BACKGROUND Fructus aurantii is a flavonoid derived from Citrus aurantium (bitter orange) that is used in traditional Chinese medicine (TCM) to treat gastric motility disorders. This study aimed to investigate the effects of low-dose and high-dose decoctions of Fructus aurantii in a rat model of functional dyspepsia (FD). MATERIAL AND METHODS Sprague-Dawley rats (n=90) were divided into nine study groups: the control group, the FD model group, the domperidone-treated (Domp) group, the low-dose raw Fructus aurantii (FA-L) group, the high-dose raw Fructus aurantii (FA-H) group, the low-dose Fructus aurantii with stir-fried wheat bran (Bran-L) group, the high-dose Fructus aurantii with stir-fried wheat bran (Bran-H) group, the low-dose Fructus aurantii with stir-fried wheat bran and honey (Honey-L) group, and the high-dose Fructus aurantii with stir-fried wheat bran and honey (Honey-H) group. The FD rat model was established by semi-starvation, followed by tail damping, stimulation, and forced exercise with fatigue. Change in weight, rate of gastric emptying and intestinal propulsion, and serum levels of leptin, motilin, vasoactive intestinal peptide (VIP), gastrin, calcitonin gene-related peptide (CGRP), ghrelin, and cholecystokinin were compared between the groups. RESULTS In the FD model group, weight, rate of gastric emptying and intestinal propulsion significantly decreased, the expression of leptin, VIP and CGRP increased, and expression of motilin, gastrin, ghrelin, and cholecystokinin significantly decreased. Treatment with low-dose Fructus aurantii with stir-fried wheat bran significantly reversed these effects. CONCLUSIONS In the rat model of FD, low-dose Fructus aurantii with stir-fried wheat bran increased gastrointestinal motility and gastrointestinal hormone levels.

Analysis of Postprandial Symptom Patterns in Subgroups of Patients With Rome III or Rome IV Functional Dyspepsia

BACKGROUND & AIMS

Among patients with functional dyspepsia (FD), there is overlap in symptoms between those in the Rome III subgroups of postprandial distress syndrome (PDS) and those with epigastric pain syndrome (EPS). The Rome IV consensus proposed to incorporate all patients with postprandial symptoms into the PDS group. We aimed to evaluate the assessment of meal-related dyspepsia symptoms in patients with FD according to the Rome III vs Rome IV subdivisions.

METHODS

Consecutive patients with FD referred for a gastric emptying test (n = 96) were asked to fill out the Rome III gastroduodenal questionnaire, with questions on meal-related occurrence. Study participants underwent a gastric emptying breath test, during which the intensity of dyspeptic symptoms (fullness, bloating, belching, nausea, epigastric pain, and burning) was scored before and up to 4 hours after a meal. We analyzed the association between the Rome subdivision and symptom severity and pattern during the breath test.

RESULTS

According to Rome III, 10% had EPS alone, 29% PDS alone, and 61% overlapping EPS and PDS. The frequency of the symptoms reported in the Rome questionnaire associated with the intensity of the symptoms during the breath test in the PDS group and in the groups with PDS and EPS overlap, but not in the group with EPS. We adapted the definition of the PDS subgroup to include patients with meal-related non-PDS symptoms (Rome IV); this reduced the proportion of patients with overlap of EPS and PDS symptoms from 61% to 18% and in this group the association of symptoms with the meal was reduced.

CONCLUSIONS

In an analysis of patients with FD, a meal induced or exacerbated symptoms in most patients. The Rome IV criteria for PDS reduce the proportions categorized as having both PDS and EPS and identify a patient group whose symptoms are associated with the meals. University hospital of Leuven study no: S55426.

Upregulation of gastric norepinephrine with beta-adrenoceptors and gastric dysmotility in a rat model of functional dyspepsia

Disordered motility is one of the most important pathogenic characteristics of functional dyspepsia (FD), although the underlying mechanisms remain unclear. Since the sympathetic system is important to the regulation of gastrointestinal motility, the present study aimed to investigate the role of norepinephrine (NE) and adrenoceptors in disordered gastric motility in a rat model with FD. The effect of exogenous NE on gastric motility in control and FD rats was measured through an organ bath study. The expression and distribution of beta-adrenoceptors were examined by real-time PCR, Western blotting and immunofluorescence. The results showed that endogenous gastric NE was elevated in FD rats, and hyperreactivity of gastric smooth muscle to NE and delayed gastric emptying were observed in the rat model of FD. The mRNA levels of beta1-adrenoceptor and norepinephrine transporter (NET) and the protein levels of beta2-adrenoceptor and NET were increased significantly in the gastric corpus of FD rats. All three subtypes of beta-adrenoceptors were abundantly distributed in the gastric corpus of rats. In conclusion, the enhanced NE and beta-adrenoceptors and NETs may be contributed to the disordered gastric motility in FD rats.

Non-pharmacological Approach in the Management of Functional Dyspepsia

Functional dyspepsia (FD) is a common functional gastrointestinal disease which bears a significant burden on society and individuals. Despite the high prevalence of FD, its pathophysiology remains poorly understood and the treatment options are limited and unsatisfactory. In the absence of effective pharmacological treatments for FD, non-pharmacological approaches, including: reassurance, lifestyle modification, psychotherapy, dietary interventions, medical food, acupuncture, and electrical stimulation and modulation are sought after by many physicians and FD patients. In this article, we review clinical studies which investigate nonpharmacological therapies for FD. We will also discuss potential mechanisms involved in the therapeutic effects of these nonpharmacological approaches. Though the evidences to support the routine use of the non-pharmacological management is still lacking, the non-invasive nature and potentially minimal side-effects of these therapies may be attractive in the FD management. In order to confirm the clinical effectiveness of these non-pharmacological approaches, more well-conducted, methodologically rigorous, and large-scaled clinical trials are required.

Current and emerging therapeutic options for the management of functional dyspepsia

Introduction: Functional Dyspepsia (FD), defined as chronic symptoms originating from the gastroduodenal region in absence of readily identifiable organic disease, is one of the most common gastrointestinal disorders. FD is divided into two subgroups: Post-Prandial Distress Syndrome (PDS) or meal-related FD, characterized by postprandial fullness and early satiation, and Epigastric Pain Syndrome (EPS) or meal-unrelated FD, characterized by epigastric pain and burning.Areas covered: This review summarizes the existing and off-label therapeutic options for FD.Expert opinion: The identification of mechanisms, the Rome IV classification, the reduction of PDS/EPS overlap and pictograms for symptom identification allow a better diagnosis and a more targeted treatment choice. Acotiamide, a first-in-class prokinetic agent available only in Japan and India, is the only agent of proven efficacy for FD, but clinicians use acid-suppressive therapy, prokinetics, neuromodulators and herbal therapies for treating FD symptoms. New emerging targets are duodenal low-grade inflammation with eosinophils and duodenal or other modified luminal microbiota.

Ameliorating effects of optimized gastric electrical stimulation and mechanisms involving nerve growth factor and opioids in a rodent model of gastric hypersensitivity

BACKGROUND

Gastric electrical stimulation (GES) has been applied to treat gastric motility disorders for decades. This study was designed to investigate the effects and mechanisms of GES for visceral hypersensitivity in a rodent model of functional dyspepsia (FD).

METHODS

Male Sprague-Dawley rat pups at 10-days old received 0.1% iodoacetamide (IA) daily for 6 days. The experiments were performed when the rats reached 8-11 weeks of age, and visceral hypersensitivity was established. Then, GES parameters were optimized and the chronic effects of GES on gastric hypersensitivity were assessed by electromyogram (EMG). Naloxone (3 mg/kg), D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP, 1 mg/kg), and anti-NGF (16 μg/kg) were individually intraperitoneally injected to investigate opioid and nerve growth factor (NGF) mechanisms. Tissues were analyzed for NGF expression.

KEY RESULTS

In the IA-treated rats, the visceromotor response to gastric distension was significantly increased, and both acute GES with optimized stimulation parameters (0.25 seconds on, 0.25 seconds off, 100 Hz, 0.25 ms, 6 mA) and chronic GES (7 days, 2 hours/day) normalized gastric hypersensitivity. The inhibitory effect of GES on gastric hypersensitivity was blocked by naloxone and CTOP. Anti-NGF normalized EMG responses in IA-treated rats. The expressions of NGF in the tissues of IA-treated rats were dramatically increased, and these increases were suppressed with GES.

CONCLUSIONS AND INFERENCES

GES with optimized parameters improves gastric hypersensitivity induced by neonatal treatment of IA mediated peripherally by suppressing NGF and via the opioid mechanism involving the µ receptor. GES as a potential therapy for treating visceral pain may be explored in clinical studies.

Reduction in Gastroesophageal Reflux Disease Symptoms Is Associated with Miso Soup Intake in a Population-Based Cross-Sectional Study: The Nagahama Study

Dietary habits and lifestyles are considered to affect the frequency of epigastric symptoms. In our previous study, we found that three amino acids in Japanese broth promoted gastric emptying. We hypothesized that a higher consumption of miso soup which was mainly composed of Japanese broth and miso paste would be associated with a lower frequency of epigastric symptoms. We conducted a cross-sectional study of the association between frequency of miso soup intake and reflux or dyspepsia symptoms in a general Japanese population. Sixteen items of dietary habits were assessed using a self-reported questionnaire, and epigastric symptoms were evaluated using the Frequency Scale for Symptoms of Gastroesophageal Reflux Disease (FSSG). We fitted generalized linear models to analyze the association between miso soup intake and FSSG, reflux, or dyspepsia scores adjusted by age, sex, body mass index (BMI), another 15 dietary habits, smoking, drinking alcohol, and unfavorable dietary behaviors. A total of 9,364 subjects were included in the analysis. Trend analysis revealed that higher frequency of miso soup intake was associated with lower FSSG scores (p<0.001). In a generalized linear model, daily intake of miso soup was associated with lower FSSG, reflux, and dyspepsia scores independent of age, sex, BMI, other 15 dietary habits, smoking, drinking alcohol, and unfavorable dietary behaviors (estimate=-0.46, -0.22, and -0.27, respectively; 95% CI=-0.83, -0.12; -0.38, -0.07; and -0.47, and -0.08, respectively). Dairy intake of miso soup was associated with lower epigastric symptoms.

Fermentable Sugar Ingestion, Gas Production, and Gastrointestinal and Central Nervous System Symptoms in Patients With Functional Disorders

BACKGROUND & AIMS

Functional gastrointestinal disorders (FGID) are defined by broad phenotypic descriptions and exclusion of recognizable disease. FGIDs cause multi-organ symptoms and abnormal results in a wide range of laboratory tests, indicating broad mechanisms of pathogenesis. Many patients with FGID develop symptoms following ingestion of fermentable sugars; we investigated the associations between symptoms and intestinal gas production following sugar provocation tests to elucidate mechanisms of FGID.

METHODS

We performed fructose and lactose breath tests in 2042 patients with a diagnosis of FGID (based on Rome III criteria), referred to a gastroenterology practice from January 2008 through December 2011. Medical and diet histories were collected from all subjects. Breath samples were collected before and each hour after, for 5 hours, subjects ingested fructose (35 g) and lactose (50 g) dissolved in 300 mL water. Hydrogen and methane gas concentrations were measured and GI and non-GI symptoms were registered for 5 hours following sugar ingestion. Symptom and gas time profiles were compared, treelet transforms were used to derive data-related symptom clusters, and the symptom severity of the clusters were analyzed for their association with breath gas characteristics.

RESULTS

We identified 11 GI and central nervous system (CNS) symptom profiles and hydrogen and methane breath concentrations that changed significantly with time following sugar ingestion. Treelet transform analysis identified 2 distinct clusters, based on GI and CNS symptoms. The severity scores for the GI and CNS symptoms correlated following ingestion of sugars (all, P < .0001). However, only the GI symptoms associated with hydrogen and methane gas production (all, P < .0001).

CONCLUSIONS

In an analysis of breath test results from more than 2000 patients with FGIDs, we identified clusters of GI and CNS symptoms in response to fructose of lactose ingestion. The association between specific symptoms and breath gas concentrations indicate distinct mechanisms of FGID pathogenesis, such as changes in the microbiome or mechanical and chemical sensitization. ClinicalTrials.gov ID: NCT02085889.

New developments in the treatment of gastroparesis and functional dyspepsia

Functional dyspepsia (FD) and gastroparesis are frequent causes of upper gastrointestinal symptoms such as postprandial fullness, early satiation, epigastric pain or burning, upper abdominal bloating, bothersome belching, nausea and vomiting. The underlying pathophysiological mechanisms are heterogeneous and involved mechanisms such as abnormal gastric motility (accommodation, emptying), visceral hypersensitivity, low grade mucosal inflammation and cellular changes in enteric nerves, muscle or interstitial cells of Cajal. Patient-reported outcomes for evaluating treatment efficacy in these conditions were recently developed and validated. Prokinetic agents, which enhance gastric motility, are used for treating both gastroparesis and FD. In FD, besides acid suppressive therapy and Helicobacter pylori eradication, neuromodulators and drugs that enhance gastric accommodation can be applied. In gastroparesis, anti-emetics may also provide symptom relief. Novel approaches under evaluation in these conditions are the fundus relaxing agents acotiamide and buspirone and the antidepressant mirtazapine in FD. For gastroparesis, recently studied agents include the prokinetic ghrelin agonist relamorelin, the prokinetic serotonergic agents velusetrag and prucalopride, the anti-emetic aprepitant and per-endoscopic pyloric myotomy procedures.

Rikkunshito simultaneously improves dyspepsia correlated with anxiety in patients with functional dyspepsia: A randomized clinical trial (the DREAM study)

BACKGROUND

Functional dyspepsia (FD), a heterogeneous disorder, involves multiple pathogenetic mechanisms. Developing treatments for FD has been challenging. We performed a randomized, placebo-controlled, double-blind clinical trial to determine the efficacy of rikkunshito, a Japanese herbal medicine, in FD patients.

METHODS

FD patients (n = 192) who met the Rome III criteria without Helicobacter pylori infection, predominant heartburn, and depression were enrolled at 56 hospitals in Japan. After 2 weeks of single-blind placebo treatment, 128 patients with continuous symptoms were randomly assigned to 8 weeks of rikkunshito (n = 64) or placebo (n = 61). The primary efficacy endpoint was global assessment of overall treatment efficacy (OTE). The secondary efficacy endpoints were improvements in upper gastrointestinal symptoms evaluated by the Patient Assessment of Upper Gastrointestinal Disorders-Symptom Severity Index (PAGI-SYM), the Global Overall Symptom scale (GOS), and the modified Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease (m-FSSG), and psychological symptoms evaluated by the Hospital Anxiety and Depression Scale (HADS).

KEY RESULTS

Rikkunshito increased OTE compared to placebo at 8 weeks (P = .019). Rikkunshito improved upper gastrointestinal symptoms (PAGI-SYM, GOS, and m-FSSG) at 8 weeks, especially postprandial fullness/early satiety (P = .015 and P = .001) and bloating (P = .007 and P = .002) of the PAGI-SYM subscales at 4 weeks and 8 weeks. Improvement of HADS at 8 weeks (P = .027) correlated with those of PAGI-SYM (r = .302, P = .001), GOS (r = .186, P = .044), and m-FSSG (r = .462, P < .001), postprandial fullness/early satiety (r = .226, P = .014), dyspepsia (r = .215, P = .019), and PDS (r = .221, P = .016).

CONCLUSION & INFERENCES

Rikkunshito may be beneficial for FD patients to simultaneously treat gastrointestinal and psychological symptoms.

Systematic review: Disease-specific instruments to assess gastrointestinal symptoms in functional dyspepsia

BACKGROUND

Functional dyspepsia (FD) is a common functional gastrointestinal disorder with incompletely understood pathophysiology and heterogeneous symptom presentation. Assessment of treatment efficacy in FD is a methodological challenge as response to treatment must be assessed primarily by measuring subjective symptoms. Therefore, the use of patient-reported outcome measures (PROMs) is recommended by regulatory authorities to assess gastrointestinal symptoms in clinical trials for FD. In the last decades, a multitude of outcome measures has been developed. However, currently no PROM has been approved by the regulatory authorities, and no consensus has been reached with regard to the most relevant outcome measure in FD.

PURPOSE

This systematic review discusses the available disease-specific outcome measures for assessment of FD symptoms with psychometric validation properties, strengths, and limitations. Moreover, recommendations for use of current available outcome measures are provided, and potential areas of future research are discussed.

Choosing an Animal Model for the Study of Functional Dyspepsia

Functional dyspepsia (FD) is a common functional gastrointestinal disorder with pain or discomfort in the upper abdomen as the main characteristic. The prevalence of FD worldwide varies between 5% and 11%. This condition adversely affects attendance and productivity in the workplace. Emerging evidence is beginning to unravel the pathophysiologies of FD, and new data on treatment are helping to guide evidence-based practice. In order to better understand the pathophysiologies of FD and explore better treatment options, various kinds of animal models of FD have been developed. However, it is unclear which of these models most closely mimic the human disease. This review provides a comprehensive overview of the currently available animal models of FD in relationship to the clinical features of the disease. The rationales, methods, merits, and disadvantages for modelling specific symptoms of FD are discussed in detail.

The effect of mirtazapine on gastric accommodation, gastric sensitivity to distention, and nutrient tolerance in healthy subjects

BACKGROUND

Disturbances of gastric motor function of functional dyspepsia (FD) have been implicated in the pathogenesis of the symptoms, and hence, motility modifying agents are considered for its treatment. Mirtazapine was recently shown to improve symptoms and increase nutrient tolerance in FD patients with weight loss. We aim to evaluate the effect of mirtazapine on gastric sensorimotor function in healthy volunteers (HV).

METHODS

Thirty-one HV underwent an intragastric pressure (IGP) and barostat measurements on separate days before and after 3 weeks of placebo or mirtazapine (15 mg). Gastric compliance, sensitivity and accommodation (GA) measured by the barostat. GA was quantitated as the difference (delta) in intra-balloon volume before and after ingestion of 200 mL of a nutrient drink (ND). GA measured by IGP was quantitated as the drop of IGP from baseline during the intragastric infusion of ND until maximal satiation.

KEY RESULTS

Mirtazapine significantly increased the bodyweight of subjects (67.8±3.7 to 69.1±3.7 kg; P=.01). Barostat results showed no effect on gastric compliance, sensitivity, and GA. Nutrient tolerance was not affected after treatment (1170±129.4 vs 1104±133.6 kcal; P=.4), and mirtazapine was associated with lower symptom ratings. The IGP drop during meal ingestion was significantly suppressed (area under the curve: -43.3±4.5 mm Hg vs -28.9±3.1 mm Hg; P=.005).

CONCLUSIONS & INFERENCES

In HVs, the occurrence of weight gain and decreased meal-induced symptoms in spite of a suppressed meal-induced IGP drop, point towards a central mode of action. Mirtazapine does not display changes in gastric sensorimotor function that could explain its beneficial effects on symptoms and nutrient tolerance in FD.

A randomized placebo-controlled trial on the effects of Menthacarin, a proprietary peppermint- and caraway-oil-preparation, on symptoms and quality of life in patients with functional dyspepsia

BACKGROUND

Functional dyspepsia (FD) is a very common condition affecting more than 10% of the population. While there is no cure, a few drugs have been found to be effective for the relief of symptoms, although most are only effective in a subgroup of patients. We assess and compare the efficacy of a fixed peppermint/caraway-oil-combination (Menthacarin) on symptoms and quality of life (QoL) in patients with FD symptoms consistent with epigastric pain syndrome (EPS) and postprandial distress syndrome (PDS).

METHODS

In a prospective, double-blind, multicenter trial, 114 outpatients with chronic or recurrent FD were randomized and treated for 4 weeks with the proprietary peppermint- and caraway-oil-preparation Menthacarin or placebo (2×1 capsule/day). Improvement of abdominal pain and discomfort were used as co-primary efficacy measures (scores measured with the validated Nepean Dyspepsia Index).

KEY RESULTS

After 2 and 4 weeks, active treatment was superior to placebo in alleviating symptoms consistent with PDS and EPS (P all <.001). After 4 weeks of treatment, pain and discomfort scores improved by 7.6±4.8 and 3.6±2.5 points (full analysis set; mean±SD) for Menthacarin and by 3.4±4.3 and 1.3±2.1 points for placebo, respectively. All secondary efficacy measures showed advantages for Menthacarin.

CONCLUSIONS & INFERENCES

Menthacarin is an effective therapy for the relief of pain and discomfort and improvement of disease-specific QoL in patients with FD and significantly improves symptoms consistent with EPS and PDS.

Certain Dietary Habits Contribute to the Functional Dyspepsia in South China Rural Area

BACKGROUND Functional dyspepsia (FD) refers to a group of upper gastrointestinal syndromes, subdivided into two types: postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). The etiology of FD remains unclear; however, unhealthy dietary habit is one potential underlying cause. We aim to explore the association of poor dietary habits with FD and its subtypes. MATERIAL AND METHODS A validated epidemiological questionnaire was designed to investigate dietary habits and gastrointestinal syndromes. Citizens in the Baotun community of Dongguan were invited to complete the study questionnaire. All participants were asked to undergo a physical examination and a blinded physician interview. The study was conducted from June 2015 to June 2016. FD was diagnosed using ROME III criteria. The association between investigated dietary habits and dyspeptic symptoms were explored. RESULTS There were 1,304 adult residents recruited for the study survey; 165 residents had existing organic dyspepsia (OD), 203 residents were diagnosed with FD, and the other 936 participants, who were without dyspeptic symptoms or functional gastrointestinal diseases, were regarded as the control group. Subtype diagnosis indicated 61 participants had EPS, 66 participants had PDS, and 76 participants had coexisting EPS and PDS. Unhealthy dietary habits were more prevalent in the FD group than in the control groups (75.86% versus 37.50%; p<0.001). FD was found to be associated with irregular mealtime, dining out, fatty food, sweet food, and coffee (p<0.05). The impact of each dietary factor varied with FD subtypes. CONCLUSIONS Certain types of dietary habits were positively correlated with the prevalence of FD. FD subtypes showed relatively different associations with dietary factors.

Severely impaired gastric accommodation is a hallmark of post-Nissen functional dyspepsia symptoms

BACKGROUND

Laparoscopic Nissen fundoplication is a commonly performed antireflux surgery, after which reflux symptoms are well controlled, however, complications such as inability to belch or dyspeptic symptoms (mimicking those of functional dyspepsia [FD]) might occur. The aim of the study was to prospectively evaluate symptom pattern and underlying pathophysiological mechanisms in patients with post-Nissen dyspepsia.

METHODS

Twenty-four patients (12 f, mean age 44.5±2.8 years) with post-Nissen dyspepsia symptoms, five patients (3 f, mean age 38.8±3.2 years) with post-Nissen dysphagia symptoms and 14 pre-fundoplication patients (3 f, mean age 42.1±2.5 years) were evaluated. Patients filled out a Rome II-based dyspepsia symptom severity score, performed a gastric emptying test, and a gastric barostat study was used to evaluate the function of the proximal stomach.

KEY RESULTS

Upper abdominal bloating scores were higher in post-Nissen dyspepsia patients (P=.016) and symptoms of postprandial distress syndrome (PDS) were more present in post-Nissen dyspepsia patients compared to the other two groups (P=.07). Weight loss was significantly higher in the post-Nissen groups compared to the pre-fundoplication (P=.02). Gastric emptying rates were similar in the three groups. Gastric accommodation (GA) was significantly impaired in the post-Nissen dyspepsia group (dyspepsia -30[-86-83] vs dysphagia 163[148-203] vs pre-fundoplication 147[75-174] mL, P=.004) and the prevalence of patients with impaired GA was higher in the post-Nissen group (P=.007). Postprandial fullness was more prevalent in patients with impaired GA compared to those with normal GA (P=.01).

CONCLUSIONS AND INTERFERENCES

Patients with post-Nissen dyspepsia show a symptom pattern similar to that in FD patients with PDS, and the main underlying mechanism seems to be impaired gastric accommodation to a meal.

The Intragastric Pressure Measurement: A Novel Method to Assess Gastric Accommodation in Functional Dyspepsia Children

BACKGROUND

Impaired gastric accommodation (GA) is proposed as a main pathophysiological mechanism for functional dyspepsia (FD). At present, the gastric barostat is the criterion standard to measure GA. Hence, this procedure is invasive and it may alter gastric physiology. Recently, we proposed the measurement of intragastric pressure (IGP) by means of high-resolution manometry during nutrient intake as a potential alternative for assessing GA in adults.

OBJECTIVES

Our aim was first to study the feasibility of the IGP measurement with nutrient tolerance in children with FD and second to compare these results with young healthy adults.

METHODS

A high-resolution manometry probe and a feeding tube were positioned in the proximal stomach. The IGP was measured before and during intragastric infusion of a nutrient drink (ND, 300 kcal, 60 mL/min). Subjects were asked to score their satiation and epigastric symptoms. The test ended when the subjects scored maximal satiation.

RESULTS

A total of 15 healthy volunteers (HVs, 21.7 ± 4.7 years, 21.1 ± 0.3 kg/m) and 17 patients with FD (14.4 ± 0.7 years, 19.6 ± 0.7 kg/m) participated. Patients with FD experienced mainly from postprandial fullness (86%), epigastric pain (71%), and bloating (62%). In both groups, intragastric infusion of ND induced a drop in IGP (area above the IGP curve FD: -15.5 ± 3.5 mmHg vs HVs: -18.0 ± 8.7 mmHg; P = 0.57). Patients showed impaired nutrient tolerance compared with HVs (587.6 ± 80.2 vs 936 ± 66.2 kcal; P = 0.003). All patients and HVs tolerated the catheters and could finalize the study.

CONCLUSIONS

The measurement of IGP during intragastric ND infusion was well tolerated in children. Nutrient tolerance was reduced in children with FD compared with HVs. In the future, this may be a useful tool to assess GA accommodation and nutrient tolerance in children.

Predictors of response to a low-FODMAP diet in patients with functional gastrointestinal disorders and lactose or fructose intolerance

BACKGROUND

Diets low in fermentable sugars (low-FODMAP diets) are increasingly adopted by patients with functional gastrointestinal disorders (FGID), but outcome predictors are unclear.

AIM

To identify factors predictive of an efficacious response to a low-FODMAP diet in FGID patients with fructose or lactose intolerance thereby gaining insights into underlying mechanisms.

METHODS

Fructose and lactose breath tests were performed in FGID patients to determine intolerance (positive symptom score) and malabsorption (increased hydrogen or methane concentrations). Patients with fructose or lactose intolerance consumed a low-FODMAP diet and global adequate symptom relief was assessed after 6-8 weeks and correlated with pre-diet clinical symptoms and breath test results.

RESULTS

A total of 81% of 584 patients completing the low-FODMAP diet achieved adequate relief, without significant differences between FGID subgroups or types of intolerance. Univariate analysis yielded predictive factors in fructose intolerance (chronic diarrhoea and pruritus, peak methane concentrations and fullness during breath tests) and lactose intolerance (peak hydrogen and methane concentrations and flatulence during breath tests). Using multivariate analysis, symptom relief was independently and positively predicted in fructose intolerance by chronic diarrhoea [odds ratio (95% confidence intervals): 2.62 (1.31-5.27), P = 0.007] and peak breath methane concentrations [1.53 (1.02-2.29), P = 0.042], and negatively predicted by chronic nausea [0.33 (0.16-0.67), P = 0.002]. No independent predictive factors emerged for lactose intolerance.

CONCLUSIONS

Adequate global symptom relief was achieved with a low-FODMAP diet in a large majority of functional gastrointestinal disorders patients with fructose or lactose intolerance. Independent predictors of a satisfactory dietary outcome were only seen in fructose intolerant patients, and were indicative of changes in intestinal host or microbiome metabolism.

Effects and mechanisms of auricular electroacupuncture on gastric hypersensitivity in a rodent model of functional dyspepsia

Background

Functional dyspepsia (FD) is a common functional gastrointestinal disease, and abdominal pain is one of the main symptoms. The aim of this study was to explore the effects and mechanisms of auricular electro-acupuncture (AEA) on gastric hypersensitivity in a rodent model of FD.

Methods

Ten-day-old pups were gavaged with 0.2 ml of 0.1% iodoacetamide daily for 6 days. AEA at the “stomach” point with different parameters or sham-EA was performed on 8-week-old animals. Gastric sensitivity to gastric distention was measured under different conditions. Autonomic functions were assessed from the spectral analysis of heart rate variability (HRV) derived from the electrocardiogram. Naloxone was injected intraperitoneally before AEA to explore the opioid mechanism. Gastric emptying was measured at the end of the study.

Results

1) Gastric sensitivity to gastric distention was higher in the FD rats. AEA with parameters of 0.1s on, 0.4s off, 100Hz, 0.3ms and 0.4–0.5mA, but not other parameters or sham-EA, decreased gastric hypersensitivity in the FD rats. Naloxone did not block the effect of AEA. 2) Lower vagal activity and higher sympathovagal ratio were noted in the FD rats, compared with the controls. AEA increased vagal activity and improved sympathovagal imbalance.

Conclusions

AEA ameliorates gastric hypersensitivity in FD rats and this effect may be attributed to the improvement of sympathovagal balance.

Changes in the Interstitial Cells of Cajal and Immunity in Chronic Psychological Stress Rats and Therapeutic Effects of Acupuncture at the Zusanli Point (ST36)

Now, chronic psychological stress (CPS) related diseases are increasing. Many CPS patients have gastrointestinal complaints, immune suppression, and immune imbalance. Increasing evidence is indicating that acupuncture (AP) at the Zusanli point (ST36) can alleviate functional gastrointestinal disorders (FGID), immune suppression, and immune imbalance. However, few studies have investigated the potential mechanisms. In this study, CPS rat models were established, and electroacupuncture (EA) at ST36 was done for CPS rats. Daily food intake, weight, intestinal sensitivity, the morphology of interstitial cell of Cajal (ICC) in the small intestine, and serum indexes were measured. The study found that, in CPS rats, EA at ST36 could improve food intake, weight, visceral hypersensitivity, and immunity; in CPS rats, in small intestine, the morphology of ICCs was abnormal and the number was decreased, which may be part causes of gastrointestinal motility dysfunction. EA at ST36 showed useful therapeutic effects. The mechanisms may be partially related to its repairing effects on ICCs damages; in CPS rats, there were immune suppression and immune imbalance, which may be part causes of visceral hypersensitivity. EA at ST36 showed useful therapeutic effects. The mechanisms may be partially related to its regulation on immunity.

Assessment of Gastric Emptying in Patients with Autoimmune Gastritis

BACKGROUND AND AIM

Symptoms of patients with autoimmune gastritis are not specific, and some patients may present symptoms suggestive of delayed gastric emptying. This study aims to investigate whether any delay in gastric emptying of solid food exists in patients with autoimmune gastritis and, if so, to identify the factors that might affect delayed gastric emptying.

METHODS

A total of 165 patients (106 women) diagnosed as having autoimmune gastritis were analyzed by means of a gastric emptying test. All patients underwent a standardized scintigraphic gastric emptying study. Patients with delayed gastric emptying and normal gastric emptying tests were then compared by means of factors that might affect gastric emptying. Also 65 patients with functional dyspepsia who had a gastric emptying study constituted the control group.

RESULTS

The median gastric emptying T ½ time was 127.43 min (min-max 50-953) for patients with AIG and 81 min (min-max 21-121.6) for functional dyspepsia patients (p < 0.001), and median percent retention at 2 h was 63.8 versus 20.2 (p < 0.001). In multivariate analysis, parameters that affected gastric emptying T ½ time were found as serum gastrin level (OR 1.002, 95 % CI 1.001-1.004, p < 0.001, chronic inflammation (OR 3.689, 95 % CI 1.44-9.39, p < 0.001), and increase in the degree of the atrophy of the gastric mucosa (OR 8.96, 95 % CI 2.98-26.93, p < 0.001).

CONCLUSIONS

In patients with autoimmune gastritis, gastric emptying is generally delayed. Autoimmune gastritis is an important etiology to explain the finding of delayed gastric emptying on a radionuclide test. This new finding is likely to be relevant to clinicians when evaluating and initiating appropriate medical treatment for patients with autoimmune gastritis manifesting upper gastrointestinal symptoms.

Psychological distress in Rome III functional dyspepsia patients presenting for testing of gastric emptying

BACKGROUND

There have been conflicting results from studies that have evaluated psychological disturbances in functional dyspepsia (FD). We conducted a comprehensive survey of psychological measures in patients undergoing gastric emptying testing (GET) in order to determine the relationship among psychological distress, gastric emptying, and dyspeptic symptoms.

METHODS

Consecutive patients referred for GET were prospectively enrolled. Details regarding patient characteristics, health care utilization, dyspeptic symptoms, quality of life, and psychological dysfunction were obtained. Depression, anxiety, somatization, stress, positive and negative affect, and alexithymia were queried using validated questionnaires. We compared those dyspeptic patients who met Rome III criteria for FD to those who did not meet these criteria.

KEY RESULTS

Two hundred and nine patients (160 female; mean age 46.6 years ± 17.3 years) participated. Around 151 patients (72%) met Rome III criteria for FD. In the entire group, a high level of depression, anxiety, somatization, and perceived stress was present compared to population norms. Health care seeking behavior and symptom severity were greater in those with FD and quality of life was lower compared to non-FD. Gastric emptying did not differentiate the two groups and similar degrees of psychological distress were present whether emptying was delayed or normal.

CONCLUSIONS & INFERENCES

In patients referred for GET, substantial psychological distress is present. The degree of distress was similar regardless of whether the patient met Rome III FD criteria or not. Further evaluation of psychological dysfunction in FD patients may lead to improved diagnosis and determination of the most appropriate treatment.