Genetic factors for functional dyspepsia

Sex and Gender Differences in Overlap Syndrome of Functional Gastrointestinal Disorder and Effect of Genetic Polymorphisms in South Korea: A Long-term Follow-up Study

BACKGROUND/AIMS

Overlap functional gastrointestinal disorder (FGID) is associated with more severe gastrointestinal symptoms and lower quality of life. The aim of this study is to evaluate clinical features of non-erosive reflux disease (NERD), functional dyspepsia, irritable bowel syndrome, their overlap in terms of sex and gender, and to assess the risk factors, including genetic polymorphisms.

METHODS

A total of 494 FGIDs and 239 controls were prospectively enrolled between 2004 and 2020. FGIDs were diagnosed based on the Rome III criteria and symptoms were evaluated using a questionnaire. Follow-up questionnaires were conducted to determine the change of symptoms during the 75.8-month mean observation period. Risk factors including genetic polymorphisms in neurotransmitter receptor (SLC6A4 5-HTTLPR, GNB3, ADRA2A, CCKAR, and TRPV1) and cytokine (TNFA and IL10) genes.

RESULTS

NERD was more prevalent in men, and functional dyspepsia in women. Overlap FGIDs (n = 239) were more prevalent than nonoverlap FGIDs (n = 255) in women (P = 0.019). Anxiety and depression scores were higher in the overlaps (P = 0.012 and P < 0.001, respectively). Symptoms were more frequent and severe in the overlap FGIDs than in the non-overlaps (P < 0.001). During followup, symptoms progressed more frequently in the overlap FGIDs, especially in patients with the L/S genotype of SLC6A4 5-HTTLPR and anxiety/depression.

CONCLUSIONS

Overlap FGID patients need attention given their association with anxiety/depression and more severe symptoms, especially in women. Genetic polymorphisms also may be associated with certain symptoms of overlap FGIDs.

Sex and Gender Differences in Overlap Syndrome of Functional Gastrointestinal Disorder and Effect of Genetic Polymorphisms in South Korea: A Long-term Follow-up Study

Background/Aims

Overlap functional gastrointestinal disorder (FGID) is associated with more severe gastrointestinal symptoms and lower quality of life. The aim of this study is to evaluate clinical features of non-erosive reflux disease (NERD), functional dyspepsia, irritable bowel syndrome, their overlap in terms of sex and gender, and to assess the risk factors, including genetic polymorphisms.

Methods

A total of 494 FGIDs and 239 controls were prospectively enrolled between 2004 and 2020. FGIDs were diagnosed based on the Rome III criteria and symptoms were evaluated using a questionnaire. Follow-up questionnaires were conducted to determine the change of symptoms during the 75.8-month mean observation period. Risk factors including genetic polymorphisms in neurotransmitter receptor (SLC6A4 5-HTTLPR, GNB3, ADRA2A, CCKAR, and TRPV1) and cytokine (TNFA and IL10) genes.

Results

NERD was more prevalent in men, and functional dyspepsia in women. Overlap FGIDs (n = 239) were more prevalent than non-overlap FGIDs (n = 255) in women (P = 0.019). Anxiety and depression scores were higher in the overlaps (P = 0.012 and P < 0.001, respectively). Symptoms were more frequent and severe in the overlap FGIDs than in the non-overlaps (P < 0.001). During follow-up, symptoms progressed more frequently in the overlap FGIDs, especially in patients with the L/S genotype of SLC6A4 5-HTTLPR and anxiety/depression.

Conclusions

Overlap FGID patients need attention given their association with anxiety/depression and more severe symptoms, especially in women. Genetic polymorphisms also may be associated with certain symptoms of overlap FGIDs.

Characterizing clinical features and location-specific gene expression profiles associated with pain burden in children with functional dyspepsia

BACKGROUND

In children with functional dyspepsia (FD), genes involved in pain modulation may be differentially expressed contributing to chronic pain.

METHODS

Children with suspected FD (cases) and known eosinophilic esophagitis (controls) undergoing esophagogastroduodenoscopy completed the Rome IV Diagnostic, Pain Burden and Frequency Severity-Duration questionnaires. Two antral and two duodenal biopsies were collected and relative fold differences in gene expression for 84 pain-associated genes compared to pain-free controls were calculated.

RESULTS

Sixty-six subjects with FD (postprandial distress syndrome = 34, epigastric pain syndrome = 7, both = 25; 65% female; mean age 13.7 years) and 13 pain-free controls (8% female; mean age 12.7) were studied. There were no significant differences in antral and duodenal eosinophilic counts or distribution between the pain and pain-free groups. Pain severity and burden did not differ significantly between FD subgroups and neither measure significantly correlated with eosinophil counts in the antrum or duodenum. Analysis of 47 antral and 39 duodenal biospecimens revealed 5 candidate genes significantly associated with pain burden: antral EDN1, PTGES3 and duodenal HTR1A, P2Y1, SCN3A (p < 0.01). Subsequent stringent statistical analysis comparing those with significant pain versus no pain revealed antral PTGES3 and duodenal SCN3A were the highest priority candidate genes (p < 0.001).

CONCLUSIONS

Pain burden in pediatric FD may be linked to antral EDN1, PTGES3 and duodenal HTR1A, P2Y1, SCN3A differential expression. These genes are known to be involved in pain conduction, modulation, and neurotransmission, suggesting potential therapeutic targets for managing pain in FD.

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.

Analysis of risk factors and prevention strategies for functional delayed gastric emptying in 1243 patients with distal gastric cancer

Background

Analysis of the risk factors associated with functional delayed gastric emptying after distal gastric cancer surgery to provide a basis for further reduction of the incidence of this complication.

Methods

Total of 1382 patients with distal gastric cancer from January 2016 to October 2018 were enrolled. Correlation analysis was performed in 53 patients with FDGE by logistic regression. Subgroup risk analysis was performed in 114 patients with preoperative pyloric obstruction. A Pearson Chi-square analysis was used to compare categorical variables between normal distribution groups. Meanwhile, a t test was used to compare continuous variables between groups. Odds ratio (OR) was used for comparison of the two groups, and it was summarized with its 95% confidence interval (CI) and p value using logistic regression.

Result

In multivariable analysis, age (OR 1.081, 95% CI, 1.047–1.117), BMI (OR 1.233, 95% CI, 1.116–1.363), preoperative pyloric obstruction (OR 3.831, 95% CI, 1.829–8.023), smaller volume of residual stomach (OR 1.838, 95% CI, 1.325–6.080), and anastomosis in greater curvature perpendicular (OR 3.385, 95% CI, 1.632–7.019) and in greater curvature parallel (OR 2.375, 95% CI, 0.963–5.861) were independent risk factors of FDGE. In the preoperative pyloric obstruction group, higher BMI (OR 1.309, 95% CI, 1.086–1.579) and preoperative obstruction time (OR 1.054, 95% CI, 1.003–1.108) were independent risk factors of FDGE and preoperative gastrointestinal decompression (OR 0.231, 95% CI, 0.068–0.785) was independent protective factor of FDGE.

Conclusion

Adequate gastrointestinal decompression should be performed before the operation to reduce the incidence of postoperative gastroparesis in patients with preoperative pyloric obstruction. We also could improve the surgical methods to reduce the occurrence of FDGE, such as controlling the size of the residual stomach, ensuring blood supply. Especially selecting an appropriate stapler and anastomosis during the anastomosis process, the occurrence of FDGE can be reduced.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-020-02085-2.

Functional dyspepsia susceptibility is associated with TGFB1 gene polymorphisms (RS4803455, RS1800469) in H pylori-negative Chinese population

BACKGROUND

We previously published that altered expression of gastric TRPV1, BDNF, and peripheral cytokines was present in patients with functional dyspepsia. We herein examine whether genetic predisposition in altered biomarkers influences dyspeptic, sleep, and mood symptoms in patients with FD without previous infection.

METHODS

Consecutive adult FD patients (Rome III) with no recent history of gastroenteritis and asymptomatic age- and sex-matched healthy controls were recruited for upper endoscopy. Subjects with GERD and IBS as predominant symptoms, diabetes mellitus, current or previous H pylori infection, psychiatric illness, and recent use of NSAID or PPI were excluded. The genetic associations with dyspeptic symptoms, sleep quality, and mood symptoms were evaluated. Genetic polymorphisms in TRPV1, TGFB1, TNF, COMT, BDNF, IL6, IL8, IL10, and IL12 were analyzed.

KEY RESULTS

Twenty-nine male FD patients and 104 female FD patients were age matched (±3 years) with 81 healthy subjects. All had postprandial distress syndrome (PDS) as predominant subtype (PDS: 130, EPS: 3). SNPs in TGFB1 showed significant associations in dyspeptic patients after age and sex adjustment [for RS4803455: in the codominant model (C/A, OR = 0.34 (0.18-0.65), P = .004); in the dominant model (genotype C/C vs C/A-A/A, OR = 0.42 (0.23-0.77), P = .004); and in the overdominant model (genotype C/C-A/A vs C/A, OR = 0.38 (0.21-0.70), P < .001)] [for RS1800469: in dominant model (genotype A/A vs A/G-G/G, OR = 0.52 (0.27-0.99), P = .043)]. A allele in RS4803455 was associated with higher HADS depression score (P = .05) and epigastric burning sensation(P = .01).

CONCLUSIONS AND INFERENCES

Our data showed that dyspeptic patients predispose genetic difference in TGFB1 which may influence the severity of dyspepsia.

Pharmacological treatments for functional nausea and functional dyspepsia in children: a systematic review

INTRODUCTION

Chronic idiopathic nausea (CIN) and functional dyspepsia (FD) cause considerable strain on many children's lives and their families. Areas covered: This study aims to systematically assess the evidence on efficacy and safety of pharmacological treatments for CIN or FD in children. CENTRAL, EMBASE, and Medline were searched for Randomized Controlled Trials (RCTs) investigating pharmacological treatments of CIN and FD in children (4-18 years). Cochrane risk of bias tool was used to assess methodological quality of the included articles. Expert commentary: Three RCTs (256 children with FD, 2-16 years) were included. No studies were found for CIN. All studies showed considerable risk of bias, therefore results should be interpreted with caution. Compared with baseline, successful relief of dyspeptic symptoms was found for omeprazole (53.8%), famotidine (44.4%), ranitidine (43.2%) and cimetidine (21.6%) (p = 0.024). Compared with placebo, famotidine showed benefit in global symptom improvement (OR 11.0; 95% CI 1.6-75.5; p = 0.02). Compared with baseline, mosapride versus pantoprazole reduced global symptoms (p = 0.011; p = 0.009). One study reported no occurrence of adverse events. This systematic review found no evidence to support the use of pharmacological drugs to treat CIN or FD in children. More high-quality clinical trials are needed.

ABBREVIATIONS

AP-FGID: Abdominal Pain Related Functional Gastrointestinal Disorders; BART: Biofeedback-Assisted Relaxation Training; CIN: Chronic Idiopathic Nausea; COS: Core Outcomes Sets; EPS: Epigastric Pain Syndrome; ESPGHAN: European Society for Pediatric Gastroenterology Hepatology and Nutrition; FAP: Functional Abdominal Pain; FD: Functional Dyspepsia; GERD: Gastroesophageal Reflux Disease; GES: Gastric Electrical Stimulation; H2RAs: H2 Receptor Antagonists; IBS: irritable bowel syndrome; NASPGHAN: North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition; PDS: Postprandial Distress Syndrome; PPIs: Proton Pump Inhibitor; PROMs: Patient Reported Outcome Measures; RCTs: Randomized Controlled Trials; SSRIs: selective serotonin reuptake inhibitors; TCAs: tricyclic antidepressants.

Functional dyspepsia and duodenal eosinophilia: A new model

Functional dyspepsia (FD) is a highly prevalent disorder that affects more than 10% of the population. In the past decade, the theoretical underpinning of the concept of FD has begun to change, in light of new data on the underlying pathophysiological mechanisms of this disorder, with a focus on the duodenum. The Rome IV criteria, published in 2016, note that gastroesophageal reflux disease and irritable bowel syndrome overlap with FD more than expected by chance, suggesting that they may be part of the same disease spectrum. Infection by Helicobacter pylori (H. pylori) may explain a minority of cases of FD and in the Rome IV criteria H. pylori-associated dyspepsia (defined as symptom relief after eradication therapy) is considered a separate entity. Duodenal inflammation characterized by increased eosinophils and in some cases mast cells, may impair the intestinal barrier. Post-infectious gastroenteritis is now an established risk factor for FD. Other risk factors may include atopy, owning herbivore pets and exposure to antibiotics, together with gastroduodenal microbiome disturbances. Small bowel homing T cells and increased cytokines in the circulation occur in FD, correlating with slow gastric emptying, and a possible association with autoimmune rheumatological disease supports background immune system activation. A genetic predisposition is possible. FD has been linked to psychological disorders, but in some cases psychological distress may be driven by gut mechanisms. Therapeutic options are limited and, aside from responders to H. pylori eradication, provide only modest and temporary relief. Advances in understanding FD may alter clinical practice, and the treatment of duodenal inflammation or microbiome alterations may lead to a cure for a subset of these patients in the future.

Functional dyspepsia and gastroparesis

PURPOSE OF REVIEW

This review summarizes recent progress in the epidemiology, pathophysiology and treatment of functional dyspepsia and gastroparesis.

RECENT FINDINGS

The definition of functional dyspepsia and its subgroups has been revised in the recent Rome IV consensus. In gastroparesis, the symptom pattern and its similarities and differences from functional dyspepsia have been a focus of recent research. In functional dyspepsia, pathophysiological research continued to evaluate gastric sensorimotor dysfunctions, but low-grade inflammatory changes and loss of mucosal integrity in the duodenum is a new topic of intense research. Treatment advances include new prokinetics such as acotiamide and the ghrelin receptor agonist relamorelin. The efficacy of tricyclic antidepressants was recently reviewed and mirtazapine is a new agent used in the treatment of functional dyspepsia and gastroparesis. In gastroparesis, research has focused on the role of macrophages in loss of interstitial cells of Cajal, and on the role of pyloric resistance as a target for therapy, using botulinum toxin injection and gastric per-endoscopic pyloric myotomy.

SUMMARY

The functional dyspepsia definition and subgrouping were updated in the Rome IV consensus. Research focuses on duodenal mucosal alterations in functional dyspepsia and pyloric resistance in gastroparesis. New treatments include novel prokinetics and pylorus-directed interventions.

Functional dyspepsia susceptibility is related to CD14, GNB3, MIF, and TRPV1 gene polymorphisms in the Greek population

BACKGROUND

Functional dyspepsia (FD) susceptibility might be influenced by polymorphisms of genes related to inflammation (CD14, macrophage migration inhibitory factor [MIF]), motor (GNB3), and sensory dysfunction (GNB3, TRPV1). We examined the association between CD14 rs2569190, GNB3 rs5443, MIF rs222747, and TRPV1 rs755622 gene polymorphisms with FD (Rome III criteria) in the Greek population.

METHODS

We genotyped 174 dyspeptics (115 with epigastric pain syndrome; 41% Helicobacter pylori positive) and 181 controls using polymerase chain reaction-based methods and we measured disease symptoms' burden with a modified Gastrointestinal Symptoms Related Scale.

KEY RESULTS

Homozygous for the TT genotype and the T allele of the CD14 gene were significantly associated (OR [95% CI]) with FD (2.65 [1.42-4.94] and 1.67 [1.23-2.26], respectively). The CT, TT genotypes, and T allele frequencies of GNB3 showed also significant association with FD (2.18 [1.35-3.54], 3.46 [1.30-9.23], and 2.18 [1.48-3.19]). While heterozygous GC MIF genotype was more common in dyspeptics (1.67 [1.07-2.60]), homozygous CC genotype and the C allele of TRPV1 gene were more prevalent in controls (0.47 [0.25-0.87] and 0.69 [0.51-0.92], respectively). None of the gene polymorphism was related either to dyspepsia clinical syndrome type or to the H. pylori infection. Among dyspeptics, CD14 TT genotype was related to lower epigastric pain burden score (p<.011); CD14 CT genotype was related to higher epigastric burning and nausea burden scores (p<.04) while belching score was lower (p=.027) in MIF CG dyspeptics.

CONCLUSION & INFERENCES

Functional dyspepsia susceptibility is related to CD14, GNB3, MIF, and TRPV1 gene polymorphisms, while CD14 and MIF gene variants are also associated with dyspepsia symptoms burden.

The Role of Duodenal Inflammation in Functional Dyspepsia

Functional dyspepsia (FD) is common and significantly impairs quality of life. Symptoms of FD are considered to originate from the gastroduodenal region, classified by the Rome criteria as disorders of brain-gut interaction without structural alteration. However, it is now apparent that FD is a number of syndromes, the epigastric pain syndrome (bothersome epigastric pain or epigastric burning) and the postprandial distress syndrome (with bothersome postprandial fullness or early satiation) and there are wide-ranging symptoms and severity. The origin of these troublesome symptoms is now considered to be a result of disrupted gastroduodenal neuropathophysiology. The complexity of the syndrome indicates that there must be different triggers, supported by the limited efficacy of the many treatments available. Current research based on evidence by association suggests that duodenal contents, including the duodenal microbiome, pathogens, and allergy may be triggers of FD. Recent studies have also shown that systemic responses of increased circulating lymphocytes and elevated proinflammatory cytokines and subtle inflammation in the duodenum may accompany the onset and persistence of symptoms. This inflammatory phenotype is characterized by innate inflammation, an eosinophil infiltrate in the duodenum in FD in those with postprandial distress syndrome. Routine histopathology practice does not quantify these cells so the status of FD is not yet appreciated as an inflammatory condition. Thus functional is becoming inflammatory and this breakthrough in understanding that functional does not necessarily mean no, but subtle pathology, may improve therapeutic options, which are currently aimed at symptom relief rather than targeted at underlying pathology.

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.

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.

Immune dysregulation in the functional gastrointestinal disorders

Gastrointestinal conditions may be broadly classified into two: organic and functional disease, with functional disorders accounting for the majority of patients with chronic gastrointestinal symptoms. Functional gastrointestinal disorders (FGIDs) present with no obvious pathology or well-accepted biochemical mechanism and, as such, treatment strategies are limited and focus on symptoms rather than cure. Irritable bowel syndrome and functional dyspepsia are the most widely recognised FGIDs, and there is a growing body of evidence to suggest an underlying inflammatory phenotype in subsets with these conditions. Here, we discuss the current knowledge of immune involvement in FGIDs and the commonalities between the different manifestations of FGIDs and propose a new hypothesis, potentially defining an underlying immunopathological basis of these conditions.

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.

Incidence and psychological-behavioral characteristics of refractory functional dyspepsia: A large, multi-center, prospective investigation from China

AIM: To explore the incidence and psychological and behavioral characteristics of refractory functional dyspepsia (RFD) in China.

METHODS: The subjects of this study were 1341 new outpatients with functional dyspepsia (FD) who were diagnosed according to the Rome III criteria at four hospitals in Guangdong Province between June and September 2012, and 100 healthy volunteers. All subjects completed questionnaires and scales administered.

RESULTS: Three-hundred and twenty-seven of the 1341 patients with FD had RFD (24.4%). Patients with RFD had a longer disease duration and a more severe form of the disease than patients with non-refractory FD (NRFD). The prevalence of depression and anxiety symptoms was higher in patients with RFD than in patients with NRFD. The prevalence of unhealthy eating behaviors, lack of physical activity, and sleeping disorders was higher in patients with RFD than in patients with NRFD. Patients with RFD sought medical advice on more occasions and spent more money on treatment than patients with NRFD. Finally, patients with RFD had poorer quality of life than patients with NRFD.

CONCLUSION: RFD is not rare in clinical practice and should get attention by patients and doctors because of its long duration, severe symptoms, and associations with abnormal psychology and poor quality of life.

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.

Leu72Met408 Polymorphism of the Ghrelin Gene Is Associated With Early Phase of Gastric Emptying in the Patients With Functional Dyspepsia in Japan

Background/Aims

There are no available data about the relationship between ghrelin gene genotypes and early phase of gastric emptying in functional dyspepsia (FD) as defined by Rome III classification.

Methods

We enrolled 74 patients presenting with typical symptoms of FD and 64 healthy volunteers. Gastric motility was evaluated using the ¹³C-acetate breath test. We used Rome III criteria to evaluate upper abdominal symptoms and self-rating questionnaires for depression (SRQ-D) scores to determine status of depression. The Arg51Gln (346G>A), preproghrelin (3056T>C), Leu72Met (408C>A), Gln90Leu (3412T>A) and G-protein β3 (825C>T) polymorphisms were analyzed in the DNA from blood samples of enrolled subjects. Genotyping was performed by polymerase chain reaction.

Results

There was a significant relationship between the Gln90Leu3412 genotype and SRQ-D score in FD patients (P = 0.009). Area under the curve at 15 minutes (AUC₁₅) value was significantly associated with the Leu72Met408 genotype (P = 0.015) but not with entire gastric emptying.

Conclusions

The Leu72Met (408C>A) single nucleotide polymorphism was significantly associated with early phase of gastric emptying in FD patients. Further studies will be necessary to clarify the association between ghrelin gene single nucleotide polymorphisms and early phase of gastric emptying in FD patients.

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.

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.

A genetic association study of single nucleotide polymorphisms in GNβ3 and COMT in elderly patients with irritable bowel syndrome

Background

Several polymorphisms have been reported to be associated with irritable bowel syndrome (IBS), including C825T, the single nucleotide polymorphism (SNP), responsible for a truncated G protein β3 subunit (GNβ3), and the Vall158Met substitution in catechol-O-methyltransferase (COMT). We investigated the association between these mutations and the prevalence of IBS in 66 elderly Chinese patients.

Material/Methods

Sixty-six patients (over age 60 years) were diagnosed with IBS according to the Rome III criteria, and divided into 3 groups based on symptom presentation. The groups consisted of 7 patients with constipation, 46 patients with diarrhea, and 13 patients with both or neither symptoms. We enrolled 115 age-matched individuals without IBS as the control group. All patients were evaluated by using the Geriatric Depression Scale, disease progression was recorded, and GNβ3 and COMT were genotyped by PCR.

Results

There was no significant difference in GNβ3 C825T genotype distribution and allele frequency between the 2 groups. In contrast, compared with control subjects, COMT 158Met was significantly more prevalent in the IBS group (P=0.040) and significantly more prevalent in patients with diarrhea (P=0.029). 158Met was also more prevalent in those patients who had experienced symptoms for over 5 years (P=0.022).

Conclusions

In elderly Chinese patients, the 158Met SNP in COMT is associated with IBS pathogenesis, but the GNβ3-C825T SNP is not associated with IBS pathogenesis.

Distributions of Sasang constitutions and six syndromes in patients with functional dyspepsia and healthy subjects

OBJECTIVE

To investigated the characteristics of patients with functional dyspepsia (FD) in terms of Sasang constitutional medicine.

METHODS

A total of 116 patients with FD were recruited based on diagnosis by gastroscopy and symptomatic measurements. The distributions of Sasang constitutions and six syndromes in terms of TKM theory in the patients was compared with those from 1423 healthy subjects.

RESULTS

The distribution of Sasang constitutions for the patients with FD significantly differed from that for healthy subjects, especially among women; 36.7% vs 45.6% for Taeumin, 28.9% vs 33.9% for Soumin, and 34.4% vs 20.4% for Soyangin. Our results assumed a high prevalence of Soyangin women (around 1.7 folds), and Soumin (45.2%), in particular, had a high prevalence of "deficiency and coldness of spleen and stomach" compared with Taeumin (14.9%) and Soyangin types (15.7%).

CONCLUSION

This study identified a trend for the frequency of FD and the Sasang constitutions. The findings may provide new ideas for the study of prevention and management of FD,

Duodenal epithelial transport in functional dyspepsia: Role of serotonin

AIM: To investigate functional duodenal abnormalities in functional dyspepsia (FD) and the role of serotonin (5-hydroxytryptamine, 5-HT) in mucosal ion transport and signalling.

METHODS: Duodenal mucosal biopsies were obtained from 15 patients with FD and 18 healthy controls. Immunohistochemistry was used to study the number of 5-HT-containing cells and real-time polymerase chain reaction for expression of 5-HT receptors 1A, 1B, 2A, 2B, 3A, 3B, 3C, 3D, 3E, 4 and 7, as well as expression of the serotonin re-uptake transporter (SERT) gene SLC6A4 and tryptophan hydroxylase 1 (TPH1). Biopsies were mounted in Ussing chambers for evaluation of basal and 5-HT-stimulated short-circuit current (SCC).

RESULTS: Conductance was lower in FD [42.4 ± 4.7 mS/cm² (n = 15) vs 62.5 ± 4.5 mS/cm² (n = 18), P = 0.005]. 5-HT induced a dose dependent rise in SCC in both FD (n = 8) and controls (n = 9), the rise was lower in FD (P < 0.001). Mean number of 5-HT stained cells per high power field was the same [34.4 ± 8.4 in FD (n = 15) and 30.4 ± 3.7 in controls (n = 18), P = 0.647]. The following genes were highly expressed: 5-HT receptor HTR3E, HTR4, HTR7, SERT gene (SLC6A4) and TPH1. Differences in expression levels were observed for HTR3E (higher expression in FD, P = 0.008), HTR7 (lower expression in FD, P = 0.027), SLC6A4 (higher expression in FD, P = 0.033) and TPH1 (lower expression in FD, P = 0.031).

CONCLUSION: Duodenal ion transport in response to exogenous 5-HT is abnormal in FD patients and associated with high expression of the HTR3E receptor and the serotonin transporter.

Modified chaihu shugan powder for functional dyspepsia: meta-analysis for randomized controlled trial

Context. Modified Chaihu Shugan powder (MCSP) is a popular traditional Chinese herbal formula for functional dyspepsia, which is revised from Chaihu Shugan San and recorded in a medical classic works of China. However, its role and effect in treating functional dyspepsia have not been well established. Objective. To assess the effect and safety of modified Chaihu Shugan powder for functional dyspepsia. Methods. We searched the published and unpublished studies up to August 2012. Only RCTs of modified Chaihu Shugan powder with or without prokinetic drugs versus prokinetic drugs in the patients diagnosed with functional dyspepsia were included. Results. Twenty-two clinical trials involving 1998 participants were included. There were evidences that modified Chaihu Shugan powder (RR = 1.20, 95%, CI 1.14 to 1.27) and modified Chaihu Shugan powder plus prokinetic drugs (RR = 1.18, 95%, CI 1.11 to 1.25) were significantly better treatment options than prokinetic drugs alone in improving symptoms. No serious adverse events were described in the included trials. Conclusions. This meta-analysis showed that modified Chaihu Shugan powder alone or in combination with prokinetic drugs might be more effective than prokinetic drugs alone. However, with poor methodological quality, all the included trials were at high risk of bias. Further large-scale high-quality trials are required for assessment.

Effect of Helicobacter pylori Eradication on Functional Dyspepsia

Background/Aims

This study evaluated the effect of Helicobacter pylori eradication on functional dyspepsia (FD), and the relationship between the changes of histological gastritis and FD symptom responses.

Methods

A total of 213 FD patients diagnosed by Rome III criteria were consecutively enrolled. H. pylori tests and gastritis grade by the Sydney system were performed before and 1 year after the proton pump based-eradication therapy for 7 days. Serum levels of pepsinogen, and genetic polymorphisms IL-6, IL-8 and IL-10 were investigated.

Results

Total of 91 patients completed the 1 year follow-up. When the response rate of dyspepsia was compared at 1 year between the non-eradicated group (n = 24) and eradicated group (n = 67), each group showed complete response of 62.5% and 62.7%; satisfactory response (≥ 50%) of 0.0% and 19.4%; partial response (< 50%) of 12.5% and 11.9%; and refractory response of 25.0% and 6.0%, respectively (P = 0.015). In addition, the responder group (complete + satisfactory response) at 1 year showed improvement of activity and chronic inflammation in both the antrum and corpus (all P < 0.001). Multivariate analysis showed that H. pylori eradication (OR, 5.81; 95% CI, 1.07-31.59) and symptom improvement at 3 month (OR, 28.90; 95% CI, 5.29-157.82) were associated with the improvement of dyspepsia at 1 year. Among the successfully eradicated FD patients (n = 67), male (P = 0.013) and higher initial BMI (P = 0.016) were associated with the improvement of dyspepsia at 1 year.

Conclusions

H. pylori eradication improved FD symptoms, as well as gastritis at 1 year, suggesting that inflammation mediates FD.

Why dyspepsia can occur without organic disease: pathogenesis and management of functional dyspepsia

Functional dyspepsia (FD), one of the most common conditions in medicine, is a gastrointestinal disorder in which the patient suffers from chronic dyspeptic symptoms such as epigastralgia and a heavy feeling in the stomach despite the absence of organic disease. Elucidating the pathogenesis of FD means answering the question, "Why do symptoms occur?" The factors contributing to symptom manifestation in FD probably should be divided into 3 categories: (1) physiological abnormalities that directly induce symptoms, (2) factors that modify those physiological abnormalities, and (3) factors that govern abnormal responses to stress. The symptoms of FD are directly caused by two major physiological abnormalities-abnormal gastric motility and visceral hypersensitivity-occurring in patients who have acquired excessive responsiveness to stress as a result of the environment during early life, genetic abnormalities, residual inflammation after gastrointestinal infections, or other causes, with the process modified by factors including psychophysiological abnormalities, abnormal secretion of gastric acid, Helicobacter pylori infection, diet, and lifestyle. If the basis of this model of FD pathogenesis is excessive responsiveness of gastrointestinal function to stress and external stimuli, psychosomatic approaches to alter stress perception could be important treatment options. However, in the primary care setting, the treatment of FD has focused on local gastric factors, including abnormal gastric acid secretion, abnormal gastric motility, and H. pylori infection. Acid secretion inhibitors and prokinetics have been commonly used, and H. pylori eradication therapy has been carried out, but the effectiveness of drug therapy has been limited.