Functional dyspepsia

Curcumin and proton pump inhibitors for functional dyspepsia: a randomised, double blind controlled trial

OBJECTIVE

To compare the efficacy of curcumin versus omeprazole in improving patient reported outcomes in people with dyspepsia.

DESIGN

Randomised, double blind controlled trial, with central randomisation.

SETTING

Thai traditional medicine hospital, district hospital, and university hospitals in Thailand.

PARTICIPANTS

Participants with a diagnosis of functional dyspepsia.

INTERVENTIONS

The interventions were curcumin alone (C), omeprazole alone (O), or curcumin plus omeprazole (C+O). Patients in the combination group received two capsules of 250 mg curcumin, four times daily, and one capsule of 20 mg omeprazole once daily for 28 days.

MAIN OUTCOME MEASURES

Functional dyspepsia symptoms on days 28 and 56 were assessed using the Severity of Dyspepsia Assessment (SODA) score. Secondary outcomes were the occurrence of adverse events and serious adverse events.

RESULTS

206 patients were enrolled in the study and randomly assigned to one of the three groups; 151 patients completed the study. Demographic data (age 49.7±11.9 years; women 73.4%), clinical characteristics and baseline dyspepsia scores were comparable between the three groups. Significant improvements were observed in SODA scores on day 28 in the pain (-4.83, -5.46 and -6.22), non-pain (-2.22, -2.32 and -2.31) and satisfaction (0.39, 0.79 and 0.60) categories for the C+O, C, and O groups, respectively. These improvements were enhanced on day 56 in the pain (-7.19, -8.07 and -8.85), non-pain (-4.09, -4.12 and -3.71) and satisfaction (0.78, 1.07, and 0.81) categories in the C+O, C, and O groups, respectively. No significant differences were observed among the three groups and no serious adverse events occurred.

CONCLUSION

Curcumin and omeprazole had comparable efficacy for functional dyspepsia with no obvious synergistic effect.

TRIAL REGISTRATION NUMBER

TCTR20221208003.

Postinfectious onset in functional dyspepsia is a risk factor for weight loss

BACKGROUND

Functional dyspepsia (FD) is differentiated into two subgroups: the postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). Acute gastroenteritis and Helicobacter pylori (HP) infection have been identified as risk factors for FD. It is unclear how these risk factors relate to Rome IV subgroups and their clinical impact. We aimed to study the association of postinfectious FD (PI-FD) and HP status with clinical profiles and weight loss.

METHODS

Consecutive FD patients were assessed for symptom frequency and severity. Patients were identified as PDS, EPS or the overlap group according to severity scores. Additionally, PI history and HP status were determined.

RESULTS

In a cohort of 459 FD-patients, 36% were characterized as having PDS, 9% as having EPS and 55% showed overlap. PI onset and positive HP status were reported by, respectively, 20% and 14% of patients, not significantly differing between subgroups (respectively, p = 0.31 and p = 0.40). Weight loss was reported by 63% in PDS, 36% in EPS and 56% in overlap patients (p = 0.011). Only early satiety severity correlated with more severe weight loss in the PDS (r 0.31, p < 0.0001) and overlap group (r 0.38, p < 0.0001). PI-FD patients were more likely to experience weight loss (OR 2.27, p = 0.0013). HP status was not significantly associated with weight loss (p = 0.90).

CONCLUSION

In this cohort, PI onset of FD symptoms emerged as a risk factor for weight loss, but was not associated with the symptom patterns of PDS, EPS or overlap subgroups. Patients with HP infection were not more likely to experience important weight loss.

Efficacy of massage therapy for postprandial distress syndrome: A protocol for systematic review and meta-analysis

BACKGROUND

Postprandial distress syndrome (PDS), characterized by the presence of prevalently meal-related early satiation and fullness, is a highly prevalent condition with major socioeconomic and healthcare impact. To date, there is a lack of pharmacological treatment proven value for PDS. Therefore, an ideal strategy to relieve PDS is urgently needed. In recent years, massage therapy has been increasingly accepted by PDS patients due to its lower costs, fewer unwanted side effects and safety for clinical use. In this systematic review, we aim to evaluate the effectiveness and safety of massage therapy for patients with postprandial distress syndrome.

METHODS

We will search the following electronic databases for randomized controlled trials to evaluate the effectiveness and safety of massage therapy in treating postprandial distress syndrome: Wanfang and Pubmed Database, CNKI, CENTRAL, CINAHL, and EMBASE. Each database will be searched from inception to October 2020. The entire process will include study selection, data extraction, risk of bias assessment, and meta-analyses.

RESULTS

This proposed study will evaluate the effectiveness and safety of massage therapy for patients with postprandial distress syndrome. The outcomes will include changes in PDS relief and adverse effect.

CONCLUSIONS

This proposed systematic review will evaluate the existing evidence on the effectiveness and safety of massage therapy for patients with postprandial distress syndrome.

DISSEMINATION AND ETHICS

The results of this review will be disseminated through peer-reviewed publication. Because all of the data used in this systematic review and meta-analysis has been published, this review does not require ethical approval. Furthermore, all data will be analyzed anonymously during the review process.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/9WRX8.

Gastroparesis and functional dyspepsia: different diseases or different ends of the spectrum?

PURPOSE OF REVIEW

This review assesses the relationship between gastroparesis and functional dyspepsia, in light of recent research assessing cause, pathophysiology and treatment.

RECENT FINDINGS

The Gastroparesis Cardinal Symptom Index (GCSI) lacks the ability to readily distinguish functional dyspepsia from gastroparesis based on symptoms. Although prior studies found that the extent of delay in gastric emptying did not accurately predict severity of symptoms, when optimally measured, delayed gastric emptying may in fact correlate with gastroparesis symptoms. Enteric dysmotility may be an important risk factor for gastroparesis. Altered central processing may play a role in symptom generation for both gastroparesis and functional dyspepsia based on functional brain MRI. Treatment directed towards reducing low-grade inflammation and improving mucosal barrier function in the duodenum may represent a novel therapeutic target for functional dyspepsia, whereas gastric peroral endoscopy myotomy (G-POEM) remains a promising intervention for refractory gastroparesis.

SUMMARY

Abnormalities on functional MRI of the brain have been identified in patients with functional dyspepsia and gastroparesis. Small bowel dysmotility and duodenal barrier dysfunction have been implicated in the pathophysiology of gastroparesis and functional dyspepsia, respectively. New treatments for functional dyspepsia may target low-grade duodenal inflammation and barrier dysfunction. The pylorus remains a target in gastroparesis.

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.

Prokinetics for Functional Dyspepsia: A Systematic Review and Meta-Analysis of Randomized Control Trials

OBJECTIVES

Prokinetics are recommended for the treatment of functional dyspepsia (FD) but systematic reviews give conflicting results on the efficacy of these agents. We have therefore conducted an updated systematic review to support the 2017 joint ACG/CAG dyspepsia guidelines.

METHODS

Electronic databases, including MEDLINE, EMBASE, and CENTRAL, were searched until September 2017 for randomized controlled trials (RCTs) comparing either prokinetics and placebo or two types of prokinetics to improve FD symptoms. The primary outcome was absence or improvement of dyspeptic symptoms at the end of treatment. Double-blind eligibility assessment and data extraction was performed. Pooled risk ratios of symptoms persisting or adverse events occurring, and standardized mean difference of quality-of-life (QoL) scores with 95% CI, using a random effects model, were calculated. Quality of evidence was assessed using GRADE.

RESULTS

The search identified 1388 citations; 38 studies in 35 papers were included. Of these, 29 trials comparing prokinetics with placebo were found. There was a statistically significant effect of prokinetic treatment in reducing global symptoms of FD (RR 0.81, 95% CI 0.74 to 0.89; I2 91%; NNT 7), regardless of FD subtype or ethnicity. When comparing two types of prokinetic, the most commonly used comparator was domperidone. There was no difference in reducing global symptoms (RR 0.94, 95% CI 0.83 to 1.07). QoL was not improved with prokinetic treatment. The adverse events with individual prokinetics were not different from placebo, except for cisapride. The GRADE assessment rated the quality of the evidence in each outcome as very low.

CONCLUSIONS

From the current evidence, prokinetics may be effective for the treatment in all subtypes of FD, with very low quality of evidence. There was no difference between prokinetics for dyspeptic symptom improvement. High-quality RCTs with large sample sizes of FD patients are needed to verify the efficacy of prokinetics.

Thailand Dyspepsia Guidelines: 2018

The management of dyspepsia in limited-resource areas has not been established. In 2017, key opinion leaders throughout Thailand gathered to review and evaluate the current clinical evidence regarding dyspepsia and to develop consensus statements, rationales, levels of evidence, and grades of recommendation for dyspepsia management in daily clinical practice based on the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. This guideline is mainly focused on the following 4 topics: (1) evaluation of patients with dyspepsia, (2) management, (3) special issues (overlapping gastroesophageal reflux disease/irritable bowel syndrome and non-steroidal anti-inflammatory drug/aspirin use), and (4) long-term follow-up and management to provide guidance for physicians in Thailand and other limited-resource areas managing such patients.

Real-World, Non-Interventional, Observational Study to Evaluate Effectiveness and Tolerability of Acotiamide Hydrochloride Hydrate in Treatment of Functional Dyspepsia

INTRODUCTION

Functional dyspepsia (FD) is a highly prevalent condition which reduces patients' quality of life (QoL) and imparts a significant economic burden on the healthcare system. Acotiamide is a novel prokinetic agent useful in treatment of FD, and this study evaluated the effectiveness of acotiamide hydrochloride hydrate in management of FD over a 4-week period in a real-world setting.

METHODS

This study was a prospective, observational, real-world data collection of 132 patients (85 male, 47 female) over 18 years of age diagnosed with FD as per Rome III criteria and treated with acotiamide for 4 weeks at a gastroenterology unit of a medical school in India. Those receiving prokinetics and cholinergic drugs, having any structural lesion on endoscopy, with coexisting irritable bowel syndrome and having heartburn in the past 12 weeks were excluded. Primary outcome was responders based on overall treatment efficacy (OTE) recorded on a seven-point Likert scale for postprandial distress syndrome (PDS; postprandial fullness, early satiety and upper abdominal bloating), epigastric pain syndrome (EPS; upper abdominal pain and upper abdominal discomfort) and associated symptoms (nausea, vomiting and excessive belching) at the end of 2 and 4 weeks. Secondary outcomes were elimination of symptoms of PDS, QoL assessed on the Short-Form Nepean Dyspepsia Index (SFNDI) questionnaire and clinical safety after 2 and 4 weeks.

RESULTS

The responder rates with acotiamide at 2 and 4 weeks were 51.5% and 65.9%, respectively, for PDS. Similarly, the responder rates for EPS were 31.8% and 41.7%, respectively, at 2 weeks and 4 weeks. The responder rates for associated symptoms of nausea, vomiting and excessive belching were respectively 18.2%, 17.4% and 16.7% at 2 weeks and 18.2%, 17.4% and 18.2% at 4 weeks. Symptom elimination rates were 9.8% and 18.9% for postprandial fullness, 12.9% and 22.0% for early satiety, and 18.9% and 24.2% for abdominal bloating at 2 and 4 weeks, respectively. Significant improvement (p < 0.0001) in the SFNDI total scores from 25.91 (5.00) at 2 weeks to 23.76 (4.84) at 4 weeks were found at 4 weeks compared to 2 weeks. A total of 7 (5.30%) patients reported mild adverse events which were dizziness (4), headache (3) and nausea (1).

CONCLUSION

The current study demonstrates that treatment with acotiamide improves symptoms, QoL and is well tolerated in Indian patients with FD.

TRIAL REGISTRATION

Clinical Trial Registry of India, CTRI/2017/11/010421.

FUNDING

Dr. Reddy's Laboratories, India.

Helicobacter pylori eradication: influence of interleukin-1beta -31 C/T polymorphism

Aim

To analyze the influence of the –31 C/T polymorphism of the interleukin-1β gene on Helicobacter pylori eradication therapy success in patients with functional dyspepsia.

Methods

Functional dyspepsia was diagnosed according to the Rome III criteria. All patients underwent upper gastrointestinal endoscopy, and gastric biopsies were obtained at screening and 12 months after randomization (last follow-up visit). Urease test and histological examination were performed to define the H. pylori status. Patients received twice-daily amoxicillin, clarithromycin and omeprazole for 10 days. Genotyping of the interleukin-1beta –31 C/T polymorphism (rs1143627) was performed using polymerase chain reaction-restriction fragment length polymorphism.

Results

One hundred forty-nine patients received treatment with triple therapy for H. pylori eradication. Only one patient was lost to follow-up, and adherence to study medication was 94.6%. A total of 148 patients (mean age 46.08 ± 12.24 years; 81.8% women) were evaluated for the influence of the interleukin-1beta –31 C/T polymorphism on the outcome of H. pylori eradication therapy. After treatment, bacteria were eradicated in 87% of patients (129/148). Genotype frequencies of the polymorphism were as follows: CC, 38/148 (25.7%); CT, 71/148 (47.9%); and TT, 39/148 (26.4%). Successful eradication rate was 78.9%, 94.4% and 82.1% for the CC, CT and TT genotypes, respectively. The CT genotype was significantly associated with successful H. pylori eradication (p = 0.039).

Conclusion

This study suggests that the CT genotype of the interleukin-1beta –31 C/T polymorphism plays a role in the successful eradication of H. pylori among patients with functional dyspepsia.

Minor digestive symptoms and their impact in the general population: a cluster analysis approach

BACKGROUND

The classification and treatment of patients who do not meet the criteria for a functional gastrointestinal (GI) disorder has not been well established. This study aimed to record the prevalence of minor digestive symptoms (MDSs) in the general population attempting to divide them into symptom clusters as well as trying to assess their impact and the way sufferers cope with them.

METHODS

Following face-to-face interviews, a web-based, self-administered questionnaire was designed to capture a range of GI sensations using 34 questions and 12 images depicting abdominal symptoms. A randomly selected sample of 1515 women and 409 men representing the general population in France was studied. Cluster analysis was used to identify groups of respondents with naturally co-occurring symptoms. Data were also collected on other factors such as exacerbating and relieving strategies.

RESULTS

MDSs were reported at least every 2 months in 66.5% of women and 47.7% of men. A total of 11 symptom clusters were identified: constipation-like, flatulence, abdominal pressure, abdominal swelling, acid reflux, diarrhoea-like, intestinal heaviness, intestinal pain, gurgling, burning and gastric pain. Despite being minor, these problems had a major impact on vitality and self-image as well as emotional, social and physical well-being. Respondents considered lifestyle, food and disordered function as the main factors responsible for MDSs. Physical measures and dietary modification were the most frequent strategies adopted to obtain relief.

CONCLUSIONS

MDSs are common and improved methods of recognition are needed so that better management strategies can be developed for individuals with these symptoms. The definition of symptom clusters may offer one way of achieving this goal.

A non-interventional, observational study of a fixed combination of pepsin and amino acid hydrochloride in patients with functional dyspepsia

BACKGROUND

Functional dyspepsia (FD) is a gastrointestinal disorder characterized by recurrent and diverse symptoms and pathophysiology that remains unexplained following routine clinical investigation. Enzynorm®f is a pharmaceutical preparation comprising fixed amounts of pepsin of biological origin and organically bound acid in the form of amino acid hydrochloride. It is traditionally used as a mild agent to support gastric function and to stimulate the stomach's proteolytic activities in FD.

METHODS

In a non-interventional, observational, post-marketing surveillance study, patients with an established diagnosis of FD were treated with a fixed combination of pepsin and amino acid hydrochloride taken as tablets three times daily for 6 weeks. The primary objective of this study was to assess the change in symptoms using the validated Gastrointestinal Symptom Score (GIS©). Secondary objectives included patients' assessment of their gastrointestinal symptoms as well as treatment safety and tolerability.

RESULTS

A total of 97 patients (mean age 58.4 ± 13.9 years; 63.2% females) were included in the study, with 72 data having GIS© score data at baseline and at 6 weeks, and 34 also at 3 weeks. The overall GIS© sum score decreased by 4.1 (p < 0.0001) from 11.6 (±4.8) at baseline to 7.4 (± 4.6) reflecting an improvement of clinical symptomatology after 6 weeks of treatment. In a subgroup of 70 patients who had FD meeting the Rome III criteria a GIS© score reduction of ≥50% was observed after 3 weeks treatment in 24% and in 30.8% after 6 weeks. Adverse events were mostly gastrointestinal in nature and consistent with the underlying disease; no unexpected adverse reactions were reported. Twenty-seven patients discontinued the study, mostly because of gastrointestinal symptoms.

CONCLUSION

The results of this study support the efficacy of a fixed combination of pepsin and amino acid hydrochloride for the treatment of patients with FD and also suggest good to moderate treatment tolerability. These findings should be further explored in a randomised, placebo-controlled clinical trial.

CLINICAL TRIAL REGISTRATION

This study has been retrospectively registered in the ClinicalTrials.gov registry, trial identifier NCT03076411 .

Potential rat model of anxiety-like gastric hypersensitivity induced by sequential stress

AIM

To establish a rat model of anxiety-like gastric hypersensitivity (GHS) of functional dyspepsia (FD) induced by novel sequential stress.

METHODS

Animal pups were divided into two groups from postnatal day 2: controls and the sequential-stress-treated. The sequential-stress-treated group received maternal separation and acute gastric irritation early in life and restraint stress in adulthood; controls were reared undisturbed with their mothers. Rats in both groups were followed to adulthood (8 wk) at which point the anxiety-like behaviors and visceromotor responses to gastric distention (20-100 mmHg) and gastric emptying were tested. Meanwhile, alterations in several anxiety-related brain-stomach modulators including 5-hydroxytryptamine (5-HT), γ-aminobutyric acid (GABA), brain-derived neurotrophic factor (BDNF) and nesfatin-1 in the rat hippocampus, plasma and gastric fundus and the 5-HT1A receptor (5-HT1AR) in the hippocampal CA1 subfield and the mucosa of the gastric fundus were examined.

RESULTS

Sequential-stress-treated rats simultaneously demonstrated anxiety-like behaviors and GHS in dose-dependent manner compared with the control group. Although rats in both groups consumed similar amount of solid food, the rate of gastric emptying was lower in the sequential-stress-treated rats than in the control group. Sequential stress significantly decreased the levels of 5-HT (51.91 ± 1.88 vs 104.21 ± 2.88, P < 0.01), GABA (2.38 ± 0.16 vs 5.01 ± 0.13, P < 0.01) and BDNF (304.40 ± 10.16 vs 698.17 ± 27.91, P < 0.01) in the hippocampus but increased the content of nesfatin-1 (1961.38 ± 56.89 vs 1007.50 ± 33.05, P < 0.01) in the same site; significantly decreased the levels of 5-HT (47.82 ± 2.29 vs 89.45 ± 2.61, P < 0.01) and BDNF (257.05 ± 12.89 vs 536.71 ± 20.73, P < 0.01) in the plasma but increased the content of nesfatin-1 in it (1391.75 ± 42.77 vs 737.88 ± 33.15, P < 0.01); significantly decreased the levels of 5-HT (41.15 ± 1.81 vs 89.17 ± 2.31, P < 0.01) and BDNF (226.49 ± 12.10 vs 551.36 ± 16.47, P < 0.01) in the gastric fundus but increased the content of nesfatin-1 in the same site (1534.75 ± 38.52 vs 819.63 ± 38.04, P < 0.01). The expressions of 5-HT1AR in the hippocampal CA1 subfield and the mucosa of the gastric fundus were down-regulated measured by IHC (Optical Density value: Hippocampus 15253.50 ± 760.35 vs 21149.75 ± 834.13; gastric fundus 15865.25 ± 521.24 vs 23865.75 ± 1868.60; P < 0.05, respectively) and WB (0.38 ± 0.01 vs 0.57 ± 0.03, P < 0.01) (n = 8 in each group).

CONCLUSION

Sequential stress could induce a potential rat model of anxiety-like GHS of FD, which could be used to research the mechanisms of this intractable disease.

Overlap between irritable bowel syndrome and functional dyspepsia including subtype analyses

BACKGROUND AND AIM

Coexistent gastrointestinal symptom profiles and prevalence or associated factors for the overlap between each functional dyspepsia (FD) and irritable bowel syndrome (IBS) group remain unclear. Thus, the aim of the present study was to evaluate the clinicodemographic features of FD, IBS, and IBS-FD overlap and assess the risk factors thereof, including subtype and genetic polymorphisms for IBS-FD.

METHODS

Consecutive patients were enrolled from the outpatient Gastroenterology clinics of Bundang Seoul National University Hospitals in Korea. All gastrointestinal symptoms occurring at least once per week in the previous 3 months were recorded. Diagnostic criteria of functional gastrointestinal disorders were based on the Rome III criteria. Risk factors including genetic polymorphisms of 5-HTTLPR and ADRA2A 1291 G alleles and CCK-1R intron 779T>C were assessed using a multivariate logistic regression model.

RESULTS

A total of 632 subjects (278 control subjects, 308 FD, 156 IBS, and 110 who met the criteria for both FD and IBS) were included in this study. Patients with IBS-FD overlap had more severe symptoms (such as bloating, nausea, vomiting, hard or lumpy stools, defecation straining, and a feeling of incomplete bowel movement) and higher depression scores compared with non-overlap patients. Single/divorced or widowed marital status, nausea, bloating, and a feeling of incomplete emptying after bowel movements were independent risk factors for IBS-FD overlap among IBS patients. In contrast, young age, depression, bloating, and postprandial distress syndrome were positively associated with IBS-FD overlap among FD patients. 5-HTTLPR L/L was a risk factor for the co-occurrence of IBS-C among FD patients (OR: 12.47; 95% CI: 2.00-77.75; P = 0.007).

CONCLUSIONS

Bloating was a risk factor for IBS-FD overlap. Patients with postprandial distress syndrome have a higher risk of coexisting IBS, particularly constipation-dominant IBS.

ACG and CAG Clinical Guideline: Management of Dyspepsia

We have updated both the American College of Gastroenterology (ACG) and the Canadian Association of Gastroenterology (CAG) guidelines on dyspepsia in a joint ACG/CAG dyspepsia guideline. We suggest that patients ≥60 years of age presenting with dyspepsia are investigated with upper gastrointestinal endoscopy to exclude organic pathology. This is a conditional recommendation and patients at higher risk of malignancy (such as spending their childhood in a high risk gastric cancer country or having a positive family history) could be offered an endoscopy at a younger age. Alarm features should not automatically precipitate endoscopy in younger patients but this should be considered on a case-by-case basis. We recommend patients <60 years of age have a non-invasive test Helicobacter pylori and treatment if positive. Those that are negative or do not respond to this approach should be given a trial of proton pump inhibitor (PPI) therapy. If these are ineffective tricyclic antidepressants (TCA) or prokinetic therapies can be tried. Patients that have an endoscopy where no pathology is found are defined as having functional dyspepsia (FD). H. pylori eradication should be offered in these patients if they are infected. We recommend PPI, TCA and prokinetic therapy (in that order) in those that fail therapy or are H. pylori negative. We do not recommend routine upper gastrointestinal (GI) motility testing but it may be useful in selected patients.

Peptide YY3-36 and glucagon-like peptide-1 in functional dyspepsia. Secretion and role in symptom generation

OBJECTIVE

The role of peptide YY3-36 (PYY3-36), glucagon-like peptide-1 (GLP-1), and glucose homoeostasis in symptom development in functional dyspepsia (FD) is unclear. The aim was to investigate postprandial changes in plasma PYY3-36, GLP-1, glucose and insulin, and the relationship between PYY3-36, GLP-1, dyspeptic symptoms, and satiety measurements.

MATERIALS AND METHODS

Thirty-six patients with functional dyspepsia and 18 healthy controls consumed a liquid meal at two occasions. Firstly, a fixed amount of 250 mL (300 kcal) was consumed and gastric emptying was assessed using the paracetamol method. Secondly, participants drank 75 mL (90 kcal) per five min until maximal satiety. PYY3-36, GLP-1, glucose, and insulin concentrations were assessed. Satiety measures and dyspeptic symptoms were registered using visual analogue scales.

RESULTS

Gastric emptying, glucose, PYY3-36, and GLP-1 concentrations were similar in patients and controls. Patients with epigastric pain syndrome had higher postprandial insulin levels. Patients reported more satiety, nausea, and pain. Area under the curve (AUC) for GLP-1 correlated positively to nausea in patients and negatively to nausea in controls during a single meal. AUC for PYY3-36 correlated similarly to sensation of fullness in the two groups; however, the correlation was negative for the single meal and positive for the satiety test.

CONCLUSIONS

In epigastric pain syndrome, postprandial insulin secretion seems to be increased. Neither GLP-1 nor PYY3-36 secretion is altered in functional dyspepsia, but postprandial GLP-1 secretion seems to correlate with nausea and PYY3-36 to the sensation of fullness, and therefore, these hormones might be involved in symptom generation.

Anxiety and depression in patients with functional gastrointestinal disorders: Prevalence and correlation with severity of gastrointestinal symptoms

AIM: To investigate the prevalence of anxiety or depression in patients with functional gastrointestinal disorders (FGIDs), as well as the correlation between scores of anxiety and depression and severity of FGIDs.

METHODS: Two hundred and ten patients who were diagnosed with FGIDs according to Rome Ⅲ criteria were randomly selected in the First Affiliated Hospital of Zhengzhou University, and 200 healthy persons were also selected randomly as controls. All the people were screened using the Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS). Gastrointestinal symptom rating scale (GSRS) was used to evaluate the patients whose SAS score was ≥ 50 or SDS score ≥ 53.

RESULTS: Of the 210 FGIDs patients included, 78 suffered from functional dyspepsia (FD), 79 from irritable bowel syndrome (IBS) and 53 from functional constipation (FC). The rate of anxiety or depression FGIDs was significantly higher in patients with FGIDs than in the control group (P < 0.05), but showed no significant different among different disease groups (P > 0.05). There was a positive correlation between symptom intensity and depression or anxiety in the study group (r = 0.63, r = 0.45, P < 0.01).

CONCLUSION: Anxiety, depression and other mental factors are directly related to the occurrence of FGIDs. We can predict the severity of digestive symptoms through the investigation of psychological factors and improve the therapeutic effect by combining anti-anxiety medication and psychological intervention treatment.

Emerging treatments in neurogastroenterology: Acotiamade, a novel treatment option for functional dyspepsia

BACKGROUND

Acotiamide hydrochloride (Z-338) is a new therapeutic agent for functional dyspepsia (FD). In 2013, the use of acotiamide was approved by the Japanese health insurance system.

PURPOSE

The aim of this review is to summarize the present staus of basic and clinical approach to acotiamide for the treatment of functional dyspepsia. The agent inhibits acetylcholinesterase in vitro and enhances muscle motility ex vivo. In phase-II studies, 100 mg three times daily (t.i.d.) was determined to be the optimal dose for the treatment of FD. In phase-III studies, overall treatment efficacy (OTE) was significantly better in the acotiamide group (52.2%) than in the placebo group (34.8%). However, the mechanism of its efficacy needs to be further elucidated. Acotiamide effectively improved FD symptoms, particularly postprandial distress syndrome symptoms, without causing major adverse effects.

Functional Disorders: Children and Adolescents

Characterization of childhood and adolescent functional gastrointestinal disorders (FGIDs) has evolved during the two decade long Rome process now culminating in Rome IV. The era of diagnosing a FGID only when organic disease has been excluded is waning,as we now have evidence to support symptom-based diagnosis. In child/adolescent Rome IV we extend this concept by removing the dictum that there was "no evidence for organic disease" in all definitions and replacing it with "after appropriate medical evaluation the symptoms cannot be attributed to another medical condition". This change allows the clinician to perform selective or no testing to support a positive diagnosis of a FGID. We also point out that FGIDs can coexist with other medical conditions that themselves result in gastrointestinal symptoms (e.g., inflammatory bowel disease). In Rome IV functional nausea and functional vomiting are now described. Rome III "abdominal pain related functional gastrointestinal disorders" (AP-FGID) has been changed to functional abdominal pain disorders (FAPD) and we have derived a new term, "functional abdominal pain -not otherwise specified", to describe children who do not fit a specific disorder such as irritable bowel, functional dyspepsia, or abdominal migraine. Rome IV FGID definitions should enhance clarity for both clinicians and researchers.

The Modulation of Potassium Channels in the Smooth Muscle as a Therapeutic Strategy for Disorders of the Gastrointestinal Tract

Alterations of smooth muscle contractility contribute to the pathophysiology of important functional gastrointestinal disorders (FGIDs) such as functional dyspepsia and irritable bowel syndrome. Consequently, drugs that decrease smooth muscle contractility are effective treatments for these diseases. Smooth muscle contraction is mainly triggered by Ca(2+) influx through voltage-dependent channels located in the plasma membrane. Thus, the modulation of the membrane potential results in the regulation of Ca(2+) influx and cytosolic levels. K(+) channels play fundamental roles in these processes. The open probability of K(+) channels increases in response to various stimuli, including membrane depolarization (voltage-gated K(+) [K(V)] channels) and the increase in cytosolic Ca(2+) levels (Ca(2+)-dependent K(+) [K(Ca)] channels). K(+) channel activation is mostly associated with outward K(+) currents that hyperpolarize the membrane and reduce cell excitability and contractility. In addition, some K(+) channels are open at the resting membrane potential values of the smooth muscle cells in some gut segments and contribute to set the resting membrane potential itself. The closure of these channels induces membrane depolarization and smooth muscle contraction. K(V)1.2, 1.5, 2.2, 4.3, 7.4 and 11.1, K(Ca)1.1 and 2.3, and inwardly rectifying type 6K(+) (K(ir)6) channels play the most important functional roles in the gastrointestinal smooth muscle. Activators of all these channels may theoretically relax the gastrointestinal smooth muscle and could therefore be promising new therapeutic options for FGID. The challenge of future drug research and development in this area will be to synthesize molecules selective for the channel assemblies expressed in the gastrointestinal smooth muscle.

The normoglycaemic biobreeding rat: a spontaneous model for impaired gastric accommodation

OBJECTIVE

Impaired gastric accommodation is reported in patients with functional dyspepsia (FD). Previous findings in postinfectious patients with FD suggest that low-grade inflammation and dysfunction of nitrergic nerves play a role in impaired accommodation. To date, spontaneous animal models to study the relationship between these changes are lacking. We hypothesise that the normoglycaemic BioBreeding diabetes-prone (BB-DP) rat provides an animal model of inflammation-induced impaired gastric motor function.

DESIGN

Control diabetes-resistant biobreeding, normoglycaemic and hyperglycaemic BB-DP rats were sacrificed at the age of 30, 70 and 220 days and gastric fundus tissue was harvested to study nitrergic motor control, inflammation and expression of neuronal isoform of nitric oxide synthase (nNOS) and inducible isoform of nitric oxide synthase (iNOS). Nutrient-induced changes in intragastric pressure (IGP) were measured in normoglycaemic BB-DP rats to study accommodation.

RESULTS

No differences in nitrergic function and inflammation were observed between BB-DP and control rats at 30 days. The nitrergic component of the fundic muscle relaxation was reduced in BB-DP rats of 70 and 220 days. This was accompanied by a significant loss of nNOS proteins. IGP significantly increased during nutrient infusion in BB-DP rats of 220 days, indicating impaired accommodation. Infiltration of polymorphonuclear cells, increased myeloperoxidase activity and increased expression of iNOS was observed in the fundic mucosa and muscularis propria of 70-day-old and 220-day-old BB-DP rats.

CONCLUSIONS

BB-DP rats of 220 days display altered fundic motor control and impaired accommodation, which is least partially explained by loss of nitrergic function. This may be related to inflammatory changes in the neuromuscular layer, suggesting that normoglycaemic BB-DP rats provide a spontaneous model for inflammation-induced impaired gastric accommodation.

The C825T Polymorphism of the G-Protein β3 Gene as a Risk Factor for Functional Dyspepsia: A Meta-Analysis

Background. Functional dyspepsia (FD) is a functional upper gastrointestinal disorder with significant morbidity and medical costs. Previous studies investigated the association of G-protein β3 (GNB3) genetic polymorphisms with FD but with inconsistent results. Therefore, we performed a meta-analysis to derive a precise estimation of the relationship between GNB3 polymorphisms and FD. Methods. We searched different databases including PubMed, EMBASE, CNKI, and the Ovid Library to gather eligible studies on GNB3 polymorphisms and FD. The association was assessed by the odds ratio (OR) with 95% confidence intervals (CI). Results. We identified 12 studies with 1109 cases and 2853 controls for the analysis. We found no associations of GNB3 C825T polymorphism with FD in the overall population (T versus C, OR = 1.06, 95% CI: 0.96-1.18, P = 0.26; TT versus CC + CT, OR = 1.16, 95% CI: 0.97-1.39, P = 0.11; TT + CT versus CC, OR = 1.01, 95% CI: 0.77-1.31, P = 0.96; TT versus CC, OR = 1.15, 95% CI: 0.93-1.44, P = 0.20). Subgroup analyses by genotyping method indicated that the magnitude of association was strengthened for additive model (OR = 1.15, 95% CI: 1.07-2.24, P = 0.02). Sensitivity analysis did not reveal significant associations under all models. Conclusions. This meta-analysis demonstrates that GNB3 C825T polymorphism may not be a risk factor for FD.

Topological Alterations of the Intrinsic Brain Network in Patients with Functional Dyspepsia

BACKGROUND/AIMS

Previous studies reported that integrated information in the brain ultimately determines the subjective experience of patients with chronic pain, but how the information is integrated in the brain connectome of functional dyspepsia (FD) patients remains largely unclear. The study aimed to quantify the topological changes of the brain network in FD patients.

METHODS

Small-world properties, network efficiency and nodal centrality were utilized to measure the changes in topological architecture in 25 FD patients and 25 healthy controls based on functional magnetic resonance imaging. Pearson's correlation assessed the relationship of each topological property with clinical symptoms.

RESULTS

FD patients showed an increase of clustering coefficients and local efficiency relative to controls from the perspective of a whole network as well as elevated nodal centrality in the right orbital part of the inferior frontal gyrus, left anterior cingulate gyrus and left hippocampus, and decreased nodal centrality in the right posterior cingulate gyrus, left cuneus, right putamen, left middle occipital gyrus and right inferior occipital gyrus. Moreover, the centrality in the anterior cingulate gyrus was significantly associated with symptom severity and duration in FD patients. Nevertheless, the inclusion of anxiety and depression scores as covariates erased the group differences in nodal centralities in the orbital part of the inferior frontal gyrus and hippocampus.

CONCLUSIONS

The results suggest topological disruption of the functional brain networks in FD patients, presumably in response to disturbances of sensory information integrated with emotion, memory, pain modulation, and selective attention in patients.

Imaging brain mechanisms in chronic visceral pain

Chronic visceral pain syndromes are important clinical problems with largely unmet medical needs. Based on the common overlap with other chronic disorders of visceral or somatic pain, mood and affect, and their responsiveness to centrally targeted treatments, an important role of central nervous system in their pathophysiology is likely. A growing number of brain imaging studies in irritable bowel syndrome, functional dyspepsia, and bladder pain syndrome/interstitial cystitis has identified abnormalities in evoked brain responses, resting state activity, and connectivity, as well as in gray and white matter properties. Structural and functional alterations in brain regions of the salience, emotional arousal, and sensorimotor networks, as well as in prefrontal regions, are the most consistently reported findings. Some of these changes show moderate correlations with behavioral and clinical measures. Most recently, data-driven machine-learning approaches to larger data sets have been able to classify visceral pain syndromes from healthy control subjects. Future studies need to identify the mechanisms underlying the altered brain signatures of chronic visceral pain and identify targets for therapeutic interventions.

Physiologically-Based Pharmacokinetic and Pharmacodynamic Modeling for the Inhibition of Acetylcholinesterase by Acotiamide, A Novel Gastroprokinetic Agent for the Treatment of Functional Dyspepsia, in Rat Stomach

Purpose

Acotiamide, a gastroprokinetic agent used to treat functional dyspepsia, is transported to at least two compartments in rat stomach. However, the role of these stomach compartments in pharmacokinetics and pharmacodynamics of acotiamide remains unclear. Thus, the purpose of this study was to elucidate the relationship of the blood and stomach concentration of acotiamide with its inhibitory effect on acetylcholinesterase (AChE).

Methods

Concentration profiles of acotiamide and acetylcholine (ACh) were determined after intravenous administration to rats and analyzed by physiologically-based pharmacokinetic and pharmacodynamic (PBPK/PD) model containing vascular space, precursor pool and deep pool of stomach.

Results

Acotiamide was eliminated from the blood and stomach in a biexponential manner. Our PBPK/PD model estimated that acotiamide concentration in the precursor pool exceeded 2 μM at approximately 2 h after administration. Acotiamide inhibited AChE activity in vitro with a 50% inhibitory concentration of 1.79 μM. ACh reached the maximum concentration at 2 h after administration.

Conclusions

Our PBPK model well described the profile of acotiamide and ACh concentration in the stomach in the assumption that acotiamide was distributed by carrier mediated process and inhibited AChE in the precursor pool of stomach. Thus, Acotiamide in the precursor pool plays an important role for producing the pharmacological action.

Dyspepsia in the community: value of a community-based mailed survey to identify potential participants for a randomized clinical trial

OBJECTIVE

To assess the usefulness of a community-based mailed survey to identify participants with functional dyspepsia (FD) for a clinical trial.

MATERIAL AND METHODS

In 2008, a valid self-report questionnaire of gastrointestinal symptoms required for diagnosis of FD was mailed to randomly selected cohorts of Olmsted County, Minnesota, residents. From survey responses (54%), FD cases and controls were identified. Phone calls were completed in 2010 and 2011 to 54% of respondents offering participation to those meeting criteria.

RESULTS

Of 937 people identified from the survey, 189 cases and 265 controls were contacted by phone using four questions similar to the written survey resulting in a moderate level of agreement (Kappa 0.43, 95% CI: 0.35- 0.51; p = 0.11). The proportion reporting FD symptoms by survey was 42%, while the proportion by phone was 38%. Comparing classification of cases and controls, 118 (62%) survey cases had dyspepsia symptoms on phone screening while 53 (20%) of the survey controls reported FD symptoms. Of 171 who had symptoms, 60 (35%) declined, 33 (19%) were over study age limit, 24 (14%) had inadequate symptom levels and 36 (21%) had comorbidities. Of survey respondents contacted, six (3%) people were enrolled with two screen fails resulting in four (1%) randomized.

CONCLUSION

Agreement between survey and phone questions was modest. Classifications between case and control changed. People eligible and willing to participate were a fraction of people reporting symptoms. People participating in clinical trials do not broadly represent those in the population.

Dalitong granule combined with electroacupuncture in the treatment of functional dyspepsia: A randomized controlled trial

OBJECTIVE

To explore clinical short and long-term effect of combining dalitong granule (DG) and electroacupuncture group (EA) in the treatment of functional dyspepsia.

METHODS

Totally 640 patients with confirmed functional dyspepsia were randomly divided into 4 groups using a randomized digital table: the DG group, the EA group, the combined group and the control group, 160 cases in each group. The DG group was treated with 6 g DG 3 times daily; the EA group was treated with puncture of points Zusanli (ST36), Zhongwan (CV12), Neiguan (PC6), Taichong (LR3) and Gongsun (SP4) twice daily; the combined group with above-mentioned DG and EA; and the control group with 5 mg mosapride 3 times, 20 mg pantoprazole and 25 mg amitriptylines twice daily. The treatment course was 4 weeks for all groups. The symptom score, quality of life score by Short Form 36 Health Survey Questionnaires (SF-36), plasma motilin by radioimmunoassay, electrogastrographic frequencies by electrogastrogram (EGG) and gastric emptying by B-sonography were examined, and adverse reactions were observed before, at the end of treatment and 60 weeks post-treatment.

RESULTS

In the DG group 1 case dropped out for not taking medicine strictly and 1 case was lost to follow-up, while 1 case in the EA group and 2 cases in the combined therapy group were lost to follow-up. Compared with pre-treatment, quality of life score, plasma motilin, electrogastrographic frequencies and gastric emptying were all increased significantly, while symptom score was decreased significantly at the end of treatment in each group (P<0.01); in the combined group quality of life score, plasma motilin, electrogastrographic frequencies and gastric emptying were all significantly higher than those in the other groups, while symptom score was significantly lower than in the other groups (P<0.05). Compared with at the end of treatment, these indices changed insignificantly in the combined group and the EA group 60 weeks post-treatment (P>0.05), but the 4 increased indices were all decreased significantly, and symptom score was increased significantly in the DG and the control groups (P>0.05). The short and long-term total effective rates in the combined group were all significantly higher than those in the other treatment groups (P<0.05 or P<0.01). No serious adverse reaction occurred in the four groups.

CONCLUSION

Combined treatment of DG and EA could increase both plasma motilin and electrogastrographic frequencies, promote gastric emptying, alleviate the symptom of dyspepsia so as to increase quality of life, with better safety and long-term effect.

Therapeutic strategies for functional dyspepsia and irritable bowel syndrome based on pathophysiology

Functional gastrointestinal disorders (FGIDs) are common and distressing. They are so named because a defined pathophysiology in terms of structural or biochemical pathways is lacking. Traditionally FGIDs have been conceptualized as brain-gut disorders, with subgroups of patients demonstrating visceral hypersensitivity and motility abnormalities as well as psychological distress. However, it is becoming apparent that there are certain structural or biochemical gut alterations among subsets with the common FGIDs, most notably functional dyspepsia (FD) and irritable bowel syndrome (IBS). For example, a sodium channel mutation has been identified in IBS that may account for 2 % of cases, and subtle intestinal inflammation has been observed in both IBS and FD. Other research has implicated early life events and stress, autoimmune disorders and atopy and infections, the gut microbiome and disordered mucosal immune activation in patients with IBS or FD. Understanding the origin of symptoms in FGIDs will allow therapy to be targeted at the pathophysiological changes, not at merely alleviating symptoms, and holds hope for eventual cure in some cases. For example, there are promising developments in manipulating the microbiome through diet, prebiotics and antibiotics in IBS, and testing and treating patients for Helicobacter pylori infection remains a mainstay of therapy in patients with dyspepsia and this infection. Locally acting drugs such as linaclotide have been an advance in treating the symptoms of constipation-predominant IBS, but do not alter the natural history of the disease. A role for a holistic approach to patients with FGIDs is warranted, as brain-to-gut and gut-to-brain pathways appear to be activated.

Sasang constitution affects the prevalence of functional dyspepsia

Background

Functional dyspepsia (FD), which is a very common disorder worldwide, is known to be caused by multiple factors including environmental and genetic factors. Sasang constitutional medicine (SCM) is a component of traditional Korean medicine that emphasizes inherited characteristics of the physical and psychological patterns of a patient. This study investigated whether the prevalence of FD differs depending on Sasang classification.

Methods

A total 517 subjects (190 males and 327 females) were recruited, and interviewed for the presence of FD using a Rome III-based questionnaire. The Sasang constitution of all subjects were diagnosed using a Sasang constitutional analytical tool (SCAT). A Chi-square test was performed to compare prevalence of DF among different Sasang constitutional types.

Results

Of the 517 subjects, 115 (22.2 %) met the diagnostic criteria for FD, and the prevalence was significantly higher in females (26.9 %) than males (14.2 %, p < 0.01). The Sasang-constitution-based prevalence among all subjects was 27.5 % for Taeumin, 23.1 % for Soumin, and 16.4 % for Soyangin (p = 0.055). When compared by sex, the prevalence of FD among Sasang types showed significantly different patterns between males and females (p < 0.05); in females with FD, Taeumin predominated (32.5 % compared with 29.5 % and 18.8 % for Soumin and Soyangin, respectively; p < 0.05), whereas males with FD displayed a higher prevalence of Soumin (17.3 % compared with 9.1 % and 11.3 % for Taeumin and Soyangin, respectively; p > 0.05).

Conclusions

This study identified significant differences in FD prevalence depending on Sasang constitution and sex. Our findings provide data to guide future research on the prevention and management of FD.

Functional dyspepsia and brain-gut peptides

Functional dyspepsia (FD) is a frequently occurring gastrointestinal disorder, but its etiology and pathogenesis are still unclear because it is associated with multiple factors. As a typically physical and psychological disease, the role of psychological factors in the pathogenesis of FD involves the brain-gut axis, mainly abnormal stimulation processing by the central nervous system and abnormal levels of brain-gut peptides. Brain-gut peptides are the molecular basis of the action of the brain-gut axis, and the brain-gut axis affects the occurrence of FD by regulating the levels of brain-gut peptides. So far, 15 brain-gut peptides associated with FD have been found, which are predominantly expressed in the hypothalamus, medulla oblongata, spinal cord and gastrointestinal mucosa. The aim of this study is to clarify the relationship between brain-gut peptide levels and the occurrence of FD based on brain-gut peptide in terms of their secretion and mechanisms of action.

Emerging drugs for functional dyspepsia

INTRODUCTION

Functional dyspepsia (FD) is a relatively common gastrointestinal clinical condition that remains poorly understood. Controversies remain regarding the definition, pathophysiology and optimum treatment. The current treatment of FD is limited and no established regimen is available.

AREAS COVERED

Recent advances have improved our understanding of the pathophysiology of the disease and have led to the development of newer tailored therapies. Novel agents such as the motilin receptor agonist camicinal and the muscarinic M1 and M2 receptor antagonist acotiamide appear promising; however, the need for a safe and efficacious treatment remains largely unmet. This review describes the currently available management options for FD and critically evaluates emerging therapies.

EXPERT OPINION

The optimal treatment for FD is yet to be determined. A proton pump inhibitor or a prokinetic agent constitutes primary treatment. Helicobacter pylori testing and eradication is recommended. Based on currently available data, acotiamide appears promising, particularly in postprandial distress syndrome. Further large-scale multicentered trials are required to define the duration of treatment and the side-effect profile.

Efficacy of Jollab in the Treatment of Depression in Dyspeptic Patients

The current study aimed to evaluate the efficacy of jollab, a well-known beverage from traditional Persian medicine in the treatment of depression among patients suffering from functional dyspepsia. In a randomized, double-blind, placebo-controlled trial, a pair of 80 patients were enrolled in 2 parallel groups as Jollab and placebo. The Beck Depression Inventory–II questionnaire was used for the assessment. At all, 133 patients enrolling in the treatment and placebo groups ended the protocol. According to the outcomes, changes in scores between the 2 groups were statistically significant at the end of trial ( P ≤ .001). Taken as a whole, treatment group was significantly more effective than the placebo. Focusing on nutritional and pharmaceutical properties, jollab may be introduced not only as a medication for depression and allied ailment but also a pleasant daily drink.

Overlap in patients with dyspepsia/functional dyspepsia

Patients with dyspepsia/functional dyspepsia (FD) show frequent overlapping of other gastrointestinal (GI) diseases, such as irri-table bowel syndrome, and non-GI diseases, in addition to internal subgroup overlapping. These overlap patients have more frequent or more severe symptoms, poorer health-related quality of life and higher somatization scores, and they are more like-ly to experience anxiety, depression or insomnia compared to non-overlap patients. The higher prevalence of overlap in patients with dyspepsia/FD is not by chance, indicating common pathogeneses, including visceral hypersensitivity, altered GI motility, in-fection, and stressful early life events. There are few clinical trials targeting overlap in patients with dyspepsia/FD, and no ther-apeutic strategy has been established. Further studies in this research area are needed. In this review, we describe the epidemi-ology, pathogenesis and treatment of overlap in patients with dyspepsia/FD.(J Neurogastroenterol Motil 2014;20:447-457).

Association of SLC6A4 5-HTTLPR and TRPV1 945G>C with functional dyspepsia in Korea

BACKGROUND AND AIM

The association of various genetic polymorphisms with functional dyspepsia (FD) has been suggested, but the results were still controversial. The aim of the present study was to assess the association of GNB3 825C>T, SLC6A4 5-HTTLPR, ADRA2A-1291C>G, CCK-1R intron 779T>C, and TRPV1 945G>C polymorphisms with FD based on Rome III criteria in Korea.

METHODS

Study subjects were prospectively recruited from visitors to Seoul National University Bundang Hospital between 2009 and 2012. One hundred and twelve FD patients and 269 controls were enrolled.

RESULTS

In SLC6A4 5-HTTLPR polymorphism, the frequency of S/S genotype was significantly lower than that of L/L + L/S genotype in FD compared to controls (P < 0.05). After stratification according to Helicobacter pylori infection, the S/S genotype was significantly associated with H. pylori-positive epigastric pain syndrome (EPS) patients (adjusted odds ratio (OR) 0.46; 95% confidence interval (CI) 0.22-0.99; P = 0.048). In TRPV1 945G>C polymorphism, the frequency of C/C genotype was lower in FD compared to controls (P = 0.057). The C carrier and C/C genotype was significantly associated with postprandial distress syndrome (PDS) and EPS, respectively (adjusted OR 0.47 and 0.43; 95% CI 0.25-0.90 and 0.20-0.93; P = 0.021 and 0.033). After stratification, the significant associations remained in H. pylori-positive PDS and EPS patients (adjusted OR 0.37 and 0.28; 95% CI 0.16-0.88 and 0.09-0.85; P = 0.024 and 0.025).

CONCLUSIONS

The genetic polymorphism of SLC6A4 5-HTTLPR and TRPV1 945G>C could be one of the pathophysiological factors of FD, especially in the case of H. pylori-positive patients in Korea.

Dyspepsia and celiac disease: Prevalence, diagnostic tools and therapy

The prevalence of dyspepsia is up to 40% in population-based study. Functional dyspepsia is an exclusion diagnosis and it is classified as a chronic abdominal pain-related functional disorder, characterized by the presence of persistent or recurrent pain or discomfort centered in the upper abdomen, neither relief by defecation, nor association with the onset of a change in stool frequency or form. Celiac disease (CD) is a common autoimmune enteropathy, with a prevalence around 1% in the general population. Its diagnosis includes a serological screening and an upper gastrointestinal endoscopy with multiple biopsies. Gluten-free diet is the only effective treatment. CD diagnosis is often delayed in asymptomatic patients or in individuals with less clinical gastrointestinal symptoms. Several studies performed coeliac disease screening in patients with symptoms suggestive of dyspepsia, showing a biopsy-proved prevalence that ranged from 0.5% to 2%. The typical endoscopic markers of villous atrophy are not sufficiently sensitive, so some endoscopic techniques, such as “water immersion” and confocal endomicroscopy were proposed to improve the diagnostic sensitivity and target biopsies. A recent meta-analysis estimated that the prevalence of CD was higher in patients with dyspepsia, but not in a statistically significant way. However this assumption should be confirmed further larger studies.

Efficacy and safety of acotiamide for the treatment of functional dyspepsia: systematic review and meta-analysis

BACKGROUND

There are no treatments with established efficacy for this disorder so far.

AIM

To systematically review the efficacy of acotiamide in the treatment of patients with FD.

METHODS

We searched main electronic databases through November 2013. RCTs evaluating the efficacy of acotiamide versus placebo in FD patients were included. Pooled risk ratio (RR) with 95% confidential interval (CI) was calculated.

RESULTS

Six publications including seven RCTs were eligible for inclusion. The summary RR of overall improvement of FD symptoms in patients receiving acotiamide versus placebo was 1.29 (95% CI, 1.19-1.40, P < 0.00001; I(2) = 15%). Acotiamide improved the symptoms of patients with postprandial distress syndrome (PDS) (RR, 1.29; 95% CI, 1.09-1.53, P = 0.003; I(2) = 0%), and the summary RR for patients with epigastric pain syndrome (EPS) was 0.92 (95% CI, 0.76-1.11, P = 0.39; I(2) = 0%). Acotiamide showed a significantly beneficial effect on the elimination of some individual FD symptoms compared with placebo. Adverse events were not significantly different between acotiamide and placebo groups. Subgroup analyses suggested that acotiamide 100 mg three times daily (tid) showed consistent efficacy not only for the overall improvement but also for the elimination of some individual symptoms in FD patients.

CONCLUSIONS

Acotiamide has the potential to improve the symptoms of patients with FD, particularly of patients with PDS, without major adverse effects. The dosage of acotiamide 100 mg tid might be the appropriate dose in the treatment of FD.

Association Between SLC6A4 Serotonin Transporter Gene Lainked Polymorphic Region and ADRA2A -1291C>G and Irritable Bowel Syndrome in Korea

Background/Aims

Despite numerous studies on the relation of genetic polymorphisms with irritable bowel syndrome (IBS), the results still remain inconclusive. The aim of this study was to assess the possible association between SLC6A4 serotonin transporter gene linked polymorphic region (5-HTTLPR), ADRA2A −1291C>G, GNB3 825C>T, CCK1R intron 779T>C and TRPV1 945G>C polymorphisms and IBS based on Rome III criteria in Korea.

Methods

Study subjects were prospectively recruited from visitors to Seoul National University Bundang Hospital between July 2009 and January 2014. Ninety-nine IBS patients and 171 healthy controls were enrolled. Polymorphisms of above-mentioned 5 genes were genotyped. Serum serotonin from 101 participants was measured by ELISA and compared according to SLC6A4 5-HTTLPR polymorphisms and IBS subtypes.

Results

Regarding SLC6A4 5-HTTLPR polymorphism, L/L genotype was significantly associated with the total IBS, constipation predominant IBS (IBS-C) and mixture of diarrhea and constipation IBS (IBS-M) (adjusted OR: 4.35, 95% CI: 1.04–16.67; adjusted OR: 11.11, 95% CI: 1.69–50.00 and adjusted OR: 5.56, 95% CI: 1.05–33.33, respectively). Carrying ADRA2A −1291G allele was significantly associated with total IBS and diarrhea predominant IBS (adjusted OR: 3.37, 95% CI: 1.16–9.77 and adjusted OR: 5.64, 95% CI: 1.18–27.01, respectively). IBS-C patients showed reduced level of serum serotonin compared to controls and patients with diarrhea predominant IBS (50.2 ng/mL vs. 69.0 ng/mL and 92.9 ng/mL, P = 0.017 and P = 0.001, respectively).

Conclusions

Genetic polymorphisms of SLC6A4 5-HTTLPR and ADRA2A −1291C>G could be one of the pathophysiological factors of IBS in Korea. Reduced serum serotonin shown in the IBS-C group suggested a role of serotonin in IBS, but large study is needed for confirming genotypic difference in serum serotonin level.

K+ channels as potential targets for the treatment of gastrointestinal motor disorders

K(+) channels play important functional roles in excitable cells, as neurons and muscle cells. The activation or inhibition of K(+) channels hyperpolarizes or depolarizes the cell membrane, respectively. These effects determine in the smooth muscle decrease or increase in Ca(2+) influx through voltage-gated Ca(2+) (CaV1.2) channels and relaxation or contraction, respectively. Recent studies highlight the importance of voltage-dependent type 7 K(+) (KV7 or KCNQ) channels in regulating muscle tone and contractility in stomach and colon. KV7 channels, that include 5 subtypes (KV7.1-7.5), are activated at relatively negative potential values, close to those of the resting membrane potential for the smooth muscle cells of some segments of the gastrointestinal tract. Thus, they contribute to set the resting membrane potential and their blockade induces increase in smooth muscle contractility in stomach and colon. In addition, KV7 channel activation produces profound relaxations of gastric and colonic smooth muscle. Therefore, KV7 channel activators could be used to relax the smooth muscle and relieve symptoms in diseases such as functional dyspepsia and irritable bowel syndrome with prevalent diarrhea. The discovery of activators selective for the channel subtypes present in the smooth muscle, mainly KV7.4 and 7.5, would allow avoiding adverse cardiac and nervous system effects. A further step forward would be characterizing putative differences among the KV7 channel subtypes expressed in the various smooth muscles and synthesizing molecules specific for the gastrointestinal smooth muscle.

Dysfunctional endogenous pain modulation in patients with functional dyspepsia

BACKGROUND

Endogenous pain modulation (EPM) is central to the processing of sensory information. Visceral and somatic EPM are abnormal in irritable bowel syndrome, but have not been studied in functional dyspepsia (FD).

METHODS

Visceral EPM was assessed in 34 FD patients and 42 healthy controls. Gastric pain was induced with oral capsaicin and EPM was studied by adding heterotopic thermal foot stimulation or distraction by STROOP test. Somatic EPM was assessed using foot heat stimulation with heterotopic hand electrical stimulation.

KEY RESULTS

Endogenous pain modulation by distraction reduced mean gastric pain by 11.9 on the 0-100 visual analog scale (95% CI: 3.8-20.1) in controls (p = 0.006) and by 2.0 (-6.18 to 10.44) in FD (p = 0.6), with greater EPM in controls than in FD (difference -13.3 [-26.1 to -0.5]; p = 0.04). Endogenous pain modulation by heterotopic foot stimulation reduced gastric pain by 6.5 (-0.7 to 13.6) in controls (p = 0.07) and by 7.1 (-2.29 to 16.47) in FD (p = 0.1), with no significant difference in EPM between controls and FD (-2.0 [-14.5 to 10.5]; p = 0.75). In patients with prominent FD pain, greater pain correlated with decreased visceral EPM by distraction (r = 0.51, p = 0.04). Somatic EPM by heterotopic stimulation significantly decreased foot pain in controls (p = 0.004), but not in FD (p = 0.80).

CONCLUSIONS & INFERENCES

In FD, visceral pain modulation by distraction was dysfunctional compared to controls. Somatic pain modulation was also decreased in FD. These data and the correlation of abnormal pain modulation by distraction with clinical pain in pain-predominant FD suggest a potential pathophysiological significance of abnormal pain modulation in FD.

[Functional heartburn--update 2013]

Functional heartburn is a frequent disease which should be considered when heartburn does not respond to proton pump inhibitor (PPI) treatment. Functional heartburn is defined in the Rome-III-criteria. Differential diagnoses like gastroesophageal reflux disease (GERD), non erosive reflux disease (NERD) and hypertensive esophagus are diagnosed employing an endoscopy and a 24h-pH-study. Since clinical trials are lacking, treatment approaches are empirical. Successful treatment includes adequate information of the patient, identification of the cardinal symptom and setting of realistic goals.

Acute gastroenteritis and the risk of functional dyspepsia: a systematic review and meta-analysis

OBJECTIVES

The objective of this systematic review and meta-analysis was to estimate the risk of developing functional dyspepsia (FD) following acute infectious gastroenteritis (IGE).

METHODS

Eligible studies were identified through PubMed and EMBASE searches. Data and quality indicators were extracted by two authors from nine studies examining the risk of FD following IGE in 5,755 exposed individuals.

RESULTS

Estimates of FD risk following IGE based on a random effects model yielded a pooled odds ratio (OR) of 2.18 (95% confidence interval (CI): 1.70-2.81). Subanalyses revealed differences in the odds of FD following self-reported IGE (OR: 2.83, 95% CI: 2.10-3.81) compared with documented IGE medical encounters (OR: 1.81, 95% CI: 1.26-2.58), and a decreasing FD risk with time from IGE (≤12 months: OR: 4.76, 95% CI: 2.47-9.20 and >12 months: OR: 1.97, 95% CI: 1.51-2.56).

CONCLUSIONS

Taken together, these data suggest that the risk of developing FD is significantly increased following IGE.

Evaluation of small intestine bacterial overgrowth in patients with functional dyspepsia through H2 breath test

CONTEXT

Functional dyspepsia is a condition in which symptoms are not related to organic underlying disease; its pathogenesis is not well known. The small intestinal bacterial overgrowth (SIBO) is characterized by the increase in the number and/or type of colonic bacteria in the upper gastrointestinal tract. The hypothesis of SIBO being associated to functional dyspepsia must be considered, since the impaired motility of the gastrointestinal tract is one of the main etiologic factors involved on both pathologies.

OBJECTIVE

To determine if there is SIBO in patients with functional dyspepsia.

METHODS

Case-control study, evaluating 34 patients: 23 functional dyspeptic and 11 non-dyspeptic (control group). Questionnaire applied based on Rome III criteria. The patients underwent H2-lactulose breath test, considered positive when: H2 peak exceeding 20 ppm, in relation to fasting, or two peaks exceeding 10 ppm sustained until 60 minutes.

RESULTS

Of the 23 dyspeptic patients, 13 (56.5%) obtained positive results for SIBO trough the H2-lactulose breath test. On control group, SIBO was not observed. The association between the dyspeptic group and the control group regarding SIBO was statistically significant, with P = 0.0052. In the group of dyspeptic patients, 12 (52.2%) were using proton pump inhibitor; of these 9 (75%) were positive for SIBO. In the control group, none of the 11 patients used proton pump inhibitors and SIBO was not observed. The association of the dyspeptic group using proton pump inhibitor that were positive for SIBO and the control group was statistically significant, with P = 0.0011.

CONCLUSION

It was found that, patients with functional dyspepsia presented SIBO, when they underwent to H2-lactulose breath test, compared to the non-dyspeptic. In addition, it was observed a higher prevalence of SIBO in dyspeptic patients that were using proton pump inhibitors, compared to control group.

Developmental origins of functional dyspepsia-like gastric hypersensitivity in rats

BACKGROUND & AIMS

Gastric hypersensitivity (GHS) contributes to epigastric pain in patients with functional dyspepsia (FD); the etiology and cellular mechanisms of this dysfunction remain unknown. We investigated whether inflammatory insult to the colons of neonatal rats induced GHS in adult life.

METHODS

We used cellular, molecular, and in vivo approaches to investigate the mechanisms of GHS in adult rats subjected to neonatal colonic insult by intraluminal administration of trinitrobenzene sulfonic acid; controls received saline. Six to 8 weeks later, rats were evaluated for GHS and tissue was collected for molecular experiments.

RESULTS

Inflammatory insult to the colon on post-natal day 10 caused an aberrant increase of corticosterone on post-natal day 15 and induced GHS in adult life. We called these FD-like rats. Inhibition of glucocorticoid receptors after neonatal insult blocked the induction of GHS in adult rats. The aberrant increase of plasma corticosterone in neonates increased the plasma concentration of norepinephrine, nerve growth factor in the gastric fundus muscularis externae, brain-derived neurotrophic factor in the thoracic dorsal root ganglia and spinal cord, and down-regulated K(v)1.1 messenger RNA in thoracic dorsal root ganglia without affecting the expression of K(v)1.4, Na(v)1.8, TrpA1, TrpV1, or P2X3 in FD-like rats. Inhibition of glucocorticoid receptors during neonatal insult or the inhibition of adrenergic receptors, nerve growth factor, or brain-derived neurotrophic factor in FD-like rats suppressed GHS. The intrathecal administration of small interfering RNAs against K(v)1.1 increased GHS in naive rats.

CONCLUSIONS

Inflammatory insult to the colons of rat pups leads to GHS in adult life. GHS is caused by altered expression of genes encoding neurotrophins and ion channels, and altered activity of the sympathetic nervous system.

Visceral and somatic sensory function in functional dyspepsia

BACKGROUND

Visceral hypersensitivity is one of the proposed underlying mechanisms in functional dyspepsia (FD). It is not clear whether visceral hypersensitivity in FD is a manifestation of a central sensitization also encompassing somatic sensitization. Transient receptor potential vanilloid-1 (TRPV(1)) pathways are involved in gastric mechanosensory physiology and the TRPV(1) receptor agonist, capsaicin, has been used as a chemical stimulant.

METHODS

In this double-blind, randomized study we evaluated both visceral and somatic sensory function in 34 FD patients and 42 healthy controls using quantitative sensory testing. Visceral pain sensitivity was assessed using a validated gastric pain model with oral capsaicin capsule titration and somatic pain sensitivity was determined by foot heat and hand electric stimulation.

KEY RESULTS

The median capsaicin dose required to attain moderate pain was 0.5mg in FD and 1mg in controls (P = 0.03). At these doses, mean pain intensities on a 0-100 visual analog scale were greater for FD than controls [56.9 (95% confidence intervals, 52.2-61.5) vs 45.1 (41.6-48.6), resp.] (P = 0.005). Overall, mean somatic sensory and pain thresholds were similar in FD and control groups, but in a subgroup of FD pain hypersensitivity was seen on the hand and on the foot at different stimulation thresholds.

CONCLUSIONS & INFERENCES

A majority of patients with FD have visceral chemo-hypersensitivity involving TRPV(1) pathways. A substantial subgroup also has somatic hypersensitivity as evidence of central sensitization.

Helicobacter pylori infection in functional dyspepsia

Functional dyspepsia is the most common reason for patients to experience chronic epigastric pain or discomfort. The causes of functional dyspepsia are multifactorial but Helicobacter pylori infection is one likely candidate. Infection with this bacterial pathogen clearly results in chronic mucosal inflammation in the stomach and duodenum, which, in turn, might lead to abnormalities in gastroduodenal motility and sensitivity. Chronic gastritis might also affect a variety of endocrine functions of the stomach including the production of the gastrointestinal hormones and neurotransmitters somatostatin, gastrin and ghrelin. Although these abnormalities might generate symptoms in some patients with functional dyspepsia, the clinical evidence needs to be critically evaluated before this hypothesis can be confirmed. A Cochrane review reported that eradication of H. pylori in these patients had a small but statistically significant long-term effect on symptom relief when compared with placebo, lasting at least 12 months after 1 week of eradication therapy. The efficacy of eradication therapy was seen in all symptom subtypes of functional dyspepsia, but was more marked in Asian than Western patients. This evidence has led to alterations in most of the major guidelines throughout the world, which now recommend H. pylori eradication in patients with functional dyspepsia if they test positive for this bacterium.

Gastric hypochlorhydria is associated with an exacerbation of dyspeptic symptoms in female patients

BACKGROUND

Gender and gastric acid have been suggested to be independently involved in the pathophysiology of functional dyspepsia, but the interrelationship among gender, dyspeptic symptoms, and gastric acid secretion remains to be evaluated. We sought to explore this issue in dyspeptic patients.

METHODS

A total of 89 outpatients (male, 36; mean age, 55.6 years) with dyspeptic symptoms were analyzed. The degree of dyspeptic symptoms was evaluated and scored using a symptom questionnaire consisting of 3 subcategories: dysmotility-related symptoms, reflux-related symptoms, and epigastric pain-related symptoms. Stimulated gastric acid secretion was directly measured using an endoscopic gastrin test.

RESULTS

The total symptom scores and the epigastric pain-related symptom scores were significantly higher in female patients than in male patients. The dysmotility-related and reflux-related symptom scores were also higher, but not significantly, in the female patients. Multiple regression analysis of age, gender, habitual drinking, smoking, Helicobacter pylori infection, and gastric acid secretion revealed that gender and gastric hypochlorhydria, defined as less than 2.1 mEq/10 min in the endoscopic gastrin test, were significantly associated with higher dyspeptic symptom scores. The total scores and the dysmotility-related scores were significantly higher in the patients with gastric hypochlorhydria than in those with gastric non-hypochlorhydria, and this difference was found to be present only in females.

CONCLUSIONS

Gastric hypochlorhydria in female dyspeptic patients may be involved in the exacerbation of dyspeptic symptoms. Differences in the responsiveness to gastric hypochlorhydria between males and females may be partly responsible for the gender differences in the prevalence and severity of dyspeptic symptoms.

Dyspepsia

PURPOSE OF REVIEW

A variety of organic diseases can cause dyspepsia, but most patients with epigastric pain have functional dyspepsia. As dyspepsia is common and usually has a benign cause, it is not possible to fully investigate everyone with epigastric pain. Current recommendations suggest that young patients without alarm symptoms can be treated empirically with Helicobacter pylori test and treat and proton pump inhibitor therapy can be offered to those who are negative or remain symptomatic despite treatment for their H. pylori. Patients who remain symptomatic with this strategy may be investigated with endoscopy, but most will have functional dyspepsia.

RECENT FINDINGS

There are a large number of trials for prokinetic therapy in functional dyspepsia, but treatment efficacy is uncertain, as there is evidence of publication bias. There are very limited data for the effectiveness of tricyclic antidepressants in functional dyspepsia. There has been recent interest in the observation that patients with functional dyspepsia have increased eosinophils in the duodenum and this may be accompanied by other subtle manifestations of upregulated mucosal immunity. It is possible that this is being driven by a dietary substance or by a change in the upper gut microbiome.

SUMMARY

The initial management of dyspepsia is well established, but how to manage those who do not respond is a challenge. Future studies evaluating diet and altering the gut microbiome may give clinicians more therapeutic options.

Acotiamide, a novel gastroprokinetic for the treatment of patients with functional dyspepsia: postprandial distress syndrome

Functional dyspepsia (FD) is a highly prevalent condition with major socioeconomic and healthcare impact. To date, no pharmacological treatment for FD has been approved. The Rome consensus proposed to subdivide FD into postprandial distress syndrome (PDS), characterized by meal-related symptoms and epigastric pain syndrome, characterized by pain and burning. Acotiamide (Z-338 or YM443) is a new drug, developed for the treatment of FD. Acotiamide enhances acetylcholine release from enteric neurons through muscarinic receptor antagonism and acetycholinesterase inhibition, thereby enhancing gastric emptying and gastric accommodation. Acotiamide was evaluated in FD in clinical studies in Europe, Japan and the USA, beneficial effects were observed for the PDS symptoms of postprandial fullness and early satiation, with a dose of 100 mg three-times a day. A 4-week placebo-controlled Phase III study in PDS patients in Japan confirmed efficacy of acotiamide in relieving postprandial fullness, early satiation and upper abdominal bloating.