G-protein β3 subunit 825CC genotype is associated with postprandial distress syndrome with impaired gastric emptying and with the feeling of hunger in Japanese

Gene Polymorphisms and Susceptibility to Functional Dyspepsia: A Systematic Review and Meta-Analysis

Functional dyspepsia (FD) is a common chronic gastrointestinal disorder with a complex, undefined mechanism. Clustering of patients with FD in families highlights the role of genetic factors in the pathogenesis of FD. We performed a systematic review and meta-analysis to clarify the associations between specific gene polymorphisms and FD susceptibility. PubMed, EMBASE, the Cochrane Library, and HuGE database were searched. An additive model was adopted to determine whether previous studied genes are associated with FD susceptibility. Carriers of minor allele in GNB3 825C>T (OR = 1.15, 95% CI 0.99-1.34, P = 0.07), SCL6A4 5HTTLPR (OR = 0.92, 95% CI 0.75-1.12, P = 0.40), and CCK-1R 779T>C (OR = 0.86, 95% CI 0.72-1.03, P = 0.09) genes failed to demonstrate susceptibility to FD. In a subgroup analysis, only minor allele (T) in GNB3 825C>T was associated with an increased susceptibility to the epigastric pain syndrome subtype (OR = 1.34, 95% CI 1.10-1.63, P = 0.003). Our meta-analysis based on available studies using an additive model failed to show that GNB3, SCL6A4, and CCK-1R polymorphisms are associated with FD susceptibility.

Comparison of clinical symptoms, gastric motility and fat intake in the early chronic pancreatitis patients with anti-acid therapy-resistant functional dyspepsia patients

Background

There was no available data concerning the clinical differentiation between the updated definition of early chronic pancreatitis (ECP) and anti-acid therapy-resistant functional dyspepsia (RFD).

Aims

We aimed to determine whether clinical symptoms, gastric motility, psychogenic factors and fat intake can help distinguish early chronic pancreatitis (ECP) from anti-acid therapy-resistant functional dyspepsia patients with pancreatic enzyme abnormalities (RFD-P) and anti-acid therapy-resistant functional dyspepsia (RFD) patients using endosonography.

Methods

We enrolled 102 consecutive patients presenting with typical symptoms of RFD patients (n = 52), ECP patients (n = 25) and RFD-P patients (n = 25). ECP patients were diagnosed based on the criteria recommended by the Japan Pancreatic Association. Gastric motility was evaluated by ¹³C-acetate breath tests. Severity of duodenal inflammation was examined.

Results

24.5% of RFD patients were determined as ECP using endosonography. Abdominal pain score in Gastrointestinal Symptom Rating Scale (GSRS) in the patients with ECP was significantly lower compared to that in the patients with RFD-P. There were no significant differences in State-Trait Inventory (STAI)-state/-trait scores, Self-Rating Questionnaire for Depression (SRQ-D) scores and clinical symptoms for fat intake among three groups. The early phase of gastric emptying (AUC₅; AUC₁₅) in ECP and RFD-P patients were significantly disturbed compared to those in RFD patients.

Conclusions

Evaluation of severity of abdominal pain and measurement of the early phase of gastric emptying will be useful tools to distinguish ECP patients from RFD patients. Accurate diagnosis of ECP patients may contribute to the prevention from advancing of chronic pancreatitis.

Functional Dyspepsia: Advances in Diagnosis and Therapy

Functional dyspepsia (FD) is a common but under-recognized syndrome comprising bothersome recurrent postprandial fullness, early satiety, or epigastric pain/burning. Epidemiologically, there are two clinically distinct FD syndromes (although these often overlap clinically): postprandial distress syndrome (PDS; comprising early satiety or meal-related fullness) and epigastric pain syndrome. Symptoms of gastroesophageal reflux disease overlap with FD more than expected by chance; a subset has pathological acid reflux. The pre-test probability of FD in a patient who presents with classical FD symptoms and no alarm features is high, approximately 0.7. Coexistent heartburn should not lead to the exclusion of FD as a diagnosis. One of the most exciting observations in FD has been the consistent finding of increased duodenal eosinophilia, notably in PDS. Small bowel homing T cells, signaling intestinal inflammation, and increased cytokines have been detected in the circulation, and elevated tumor necrosis factor-α levels have been significantly correlated with increased anxiety. Postinfectious gastroenteritis is a risk factor for FD. Therapeutic options remain limited and provide only symptomatic benefit in most cases. Only one therapy is known to change the natural history of FD–Helicobacter pylori eradication. Treatment of duodenal eosinophilia is under investigation.

Epigastric pain syndrome accompanying pancreatic enzyme abnormalities was overlapped with early chronic pancreatitis using endosonography

There was not available data about the overlap between functional dyspepsia (FD) and pancreatic diseases. We aimed to determine whether epigastric pain syndrome (EPS) accompanying with pancreatic enzyme abnormalities were associated with early chronic pancreatitis proposed by Japan Pancreas Society (JPS) using endosonography. We enrolled 99 consecutive patients presenting with typical symptoms of FD, including patients with postprandial distress syndrome (PDS) (n = 59), EPS with pancreatic enzyme abnormalities (n = 41) and EPS without pancreatic enzyme abnormalities (n = 42) based on Rome III criteria. Gastric motility was evaluated using the ¹³C-acetate breath test. Early chronic pancreatitis was detected by endosonography and graded from 0 to 7. The ratio of female patients among EPS patients (34/41) with pancreatic enzyme abnormalities was significantly (p = 0.0018) higher than the ratio of female EPS patients (20/42) without it. Postprandial abdominal distention and physical component summary (PCS) scores in EPS patients with pancreatic enzyme abnormalities were significantly disturbed compared to those in EPS patients without it. Interestingly, AUC₅ and AUC₁₅ values (24.85 ± 1.31 and 56.11 ± 2.51, respectively) in EPS patients with pancreatic enzyme abnormalities were also significantly (p = 0.002 and p = 0.001, respectively) increased compared to those (19.75 ± 1.01 and 47.02 ± 1.99, respectively) in EPS patients without it. Overall, 64% of EPS patients with pancreatic enzyme abnormalities were diagnosed by endosonography as having concomitant early chronic pancreatitis proposed by JPS. Further studies are warranted to clarify how EPS patients with pancreatic enzyme abnormalities were associated with early chronic pancreatitis proposed by JPS.

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.

Improvement of meal-related symptoms and epigastric pain in patients with functional dyspepsia treated with acotiamide was associated with acylated ghrelin levels in Japan

BACKGROUND

The aim of this study is to clarify whether acotiamide and rabeprazole combination therapy can improve clinical symptoms, gastric emptying, and satisfaction with treatment in functional dyspepsia (FD) patients more effectively than acotiamide or rabeprazole monotherapy alone. We also aimed to determine whether acotiamide affects these changes via its effect on gastric emptying and appetite-related hormones such as ghrelin.

METHODS

We used Rome III criteria to evaluate upper abdominal symptoms and anxiety by the State-Trait Anxiety Inventory (STAI). Gastric motility was evaluated by the (13) C-acetate breath test. Eighty-one FD patients were treated with acotiamide (300 mg/day) (n = 35), acotiamide (300 mg/day) and rabeprazole (10 mg/day) (n = 28), or rabeprazole (10 mg/day) (n = 18) for a period of 4 weeks and followed after 4 weeks of no treatment. Adenocorticotropic hormone (ACTH), cortisol, leptin and ghrelin levels were measured in all FD patients.

KEY RESULTS

Acotiamide and rabeprazole combination therapy significantly improved postprandial distress syndrome (PDS)-like symptoms (p = 0.018, p = 0.04 and p = 0.041, respectively) and epigastric pain (p = 0.024) as wells as STAI-state scores (p = 0.04) compared to rabeprazole monotherapy. Both acotiamide monotherapy, and acotiamide taken in combination with rabeprazole, significantly (p = 0.001 and p = 0.02, respectively) improved satisfaction with treatment, compared to rabeprazole monotherapy. Acotiamide and rabeprazole combination therapy had no significant effect on ACTH and cortisol levels in FD patients. Of interest, acotiamide monotherapy, and acotiamide and rabeprazole combination therapy, significantly (p < 0.0001 and p = 0.018, respectively) increased acylated ghrelin/total ghrelin ratios and significantly (p = 0.04) improved impaired gastric emptying compared to rabeprazole monotherapy.

CONCLUSIONS & INFERENCES

Further studies are warranted to clarify how acotiamide treatment improves clinical symptoms in FD patients.

Functional dyspepsia is associated with GNβ3 C825T and CCK-AR T/C polymorphism

BACKGROUND

A polymorphism (C825T) in G-protein β polypeptide-3 (GNβ3) gene alters intracellular signal transduction, which may cause motor or sensory abnormalities in the gastrointestinal tract. Cholecystokinin-A receptor (CCK-AR) gene T/C polymorphism is associated with a defective splicing of the primary transcript of CCK-AR mRNA, which may modulate satiety signal and delay gastric emptying. Therefore, we evaluated the role of these polymorphisms in patients with functional dyspepsia (FD) as compared with healthy controls (HC).

PATIENTS AND METHODS

A total of 237 consecutive patients with FD (Rome III) and 250 HC were genotyped for GNβ3 C825T and CCK-AR T/C polymorphisms (PCR-RFLP).

RESULTS

Patients with FD [173 (73%) men, age: 38 ± 12 years] were comparable with HC [195 (78%) men, age: 37 ± 12 years] with respect to age and sex. Out of 237 patients, 26 (11%) had epigastric pain syndrome (EPS), 55 (23.2%) had postprandial distress syndrome (PDS), and 156 (65.8%) had EPS-PDS overlap. Among 237 patients with FD, TT genotype (associated with increased intracellular signal transduction) of GNβ3 C825T polymorphism was more common among patients than among HC [26 (11%) vs. 12 (4.8%), P=0.014; odds ratio (OR): 2.47, 95% confidence interval (CI): 1.2-5.1]. CC (variant) genotype of CCK-AR T/C polymorphism was infrequent among patients than among HC [19 (8%) vs. 46 (18.4%), P=0.001; OR: 0.36, 95% CI: 0.19-0.66]. However, these polymorphisms were comparable among patients with different subtypes of FD (P=0.80 and 0.44).

CONCLUSION

TT genotype of GNβ3 C825T is more common among patients with FD than among HC, suggesting that increased signal transduction associated with this genotype may be important in its pathophysiology. However, CCK-AR polymorphism is protective against FD.

Genetics and pharmacogenetics of aminergic transmitter pathways in functional gastrointestinal disorders

Functional gastrointestinal disorders (FGIDs) are highly prevalent syndromes, without evident underlying organic causes. Their pathogenesis is multifactorial in nature, with a combination of environmental and genetic factors contributing to their clinical manifestations, for which most of current treatments are not satisfactory. It is acknowledged that amine mediators (noradrenaline, dopamine and serotonin) play pivotal regulatory actions on gut functions and visceral sensation. In addition, drugs of therapeutic interest for FGIDs act on these transmitter pathways. The present article reviews current knowledge on the impact of genetics and pharmacogenetics of aminergic pathways on FGID pathophysiology, clinical presentations, symptom severity and medical management, in an attempt of highlighting the most relevant evidence and point out issues that should be addressed in future investigations.

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.

Gene polymorphisms associated with functional dyspepsia

Functional dyspepsia (FD) is a constellation of functional upper abdominal complaints with poorly elucidated pathophysiology. However, there is increasing evidence that susceptibility to FD is influenced by hereditary factors. Genetic association studies in FD have examined genotypes related to gastrointestinal motility or sensation, as well as those related to inflammation or immune response. G-protein b3 subunit gene polymorphisms were first reported as being associated with FD. Thereafter, several gene polymorphisms including serotonin transporter promoter, interlukin-17F, migration inhibitory factor, cholecystocynine-1 intron 1, cyclooxygenase-1, catechol-o-methyltransferase, transient receptor potential vanilloid 1 receptor, regulated upon activation normal T cell expressed and secreted, p22PHOX, Toll like receptor 2, SCN10A, CD14 and adrenoreceptors have been investigated in relation to FD; however, the results are contradictory. Several limitations underscore the value of current studies. Among others, inconsistencies in the definitions of FD and controls, subject composition differences regarding FD subtypes, inadequate samples, geographical and ethnical differences, as well as unadjusted environmental factors. Further well-designed studies are necessary to determine how targeted genes polymorphisms, influence the clinical manifestations and potentially the therapeutic response in FD.

Which subtype of functional dyspepsia patients responses better to acupuncture? A retrospective analysis of a randomized controlled trial

BACKGROUND

Whether subgroups of functional dyspepsia (FD) should be treated with different approaches is controversially discussed in research. As our previous study has demonstrated the effect of acupuncture in FD treatment, we now further analyze the therapeutic effect of acupuncture in the treatment of postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS).

METHODS

A retrospective analysis was conducted in 465 eligible PDS patients and 241 EPS patients. 4 acupuncture groups (group A: specific acupoints along the stomach meridian; group B: non-specific acupoints along the stomach meridian; group C: alarm and transport acupoints; group D: specific acupoints along the gallbladder meridian) were compared with a non-acupoint sham acupuncture group and an itopride group. The patients were treated in 5 consecutive sessions per week for 4 weeks and were followed-up for 12 weeks afterwards. Primary outcome of the study was defined as response rate and symptom improvement as measured by the Symptom Index of Dyspepsia, while secondary outcome was designated as improvement in quality of life (QoL) as determined by the Nepean Dyspepsia Index.

RESULTS

Symptoms of dyspepsia and QoL were improved from baseline in all groups. In EPS patients, no statistically significant differences could be observed in response rate (p = 0.239) and symptoms improvement (p = 0.344 for epigastric pain; p = 0.465 for epigastric burning). In contrast, PDS patients of the acupuncture group A showed higher response rate (53.2% vs. 19.7%, p<0.001; 53.2% vs. 35.1%, p = 0.025) and score change in postprandial fullness (1.01 vs. 0.27, p<0.001; 1.01 vs. 0.57, p<0.001), early satiation (0.81 vs. 0.21, p<0.001; 0.81 vs. 0.39, p=0.001), and QoL (14.5 vs. 4.33, p<0.001; 14.5 vs. 8.5, p<0.001) compared to the sham acupuncture and itopride group.

CONCLUSIONS

FD patients with PDS responded better to the acupuncture therapies, especially at the specific acupoints along the stomach meridian. The positive therapeutic effect of acupuncture on PDS was correlated with the improvement in postprandial fullness.

TRIAL REGISTRATION

ClinicalTrial.gov NCT00599677.

[Current issues in functional dyspepsia]

Functional dyspepsia is one of the most common gastrointestinal disorders encountered in clinical practice. Functional dyspepsia is currently defined by Rome III criteria as the chronic dyspeptic symptoms (postprandial fullness, early satiety, epigastric pain or burning) in the absence of underling structural or metabolic disease that readily explain the symptoms. According to the Rome III consensus, functional dyspepsia can be subdivided into postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). Although the Rome III criteria have been published more than 8 years ago, not much effort has been put into validating these criteria and direct scientific evidence supporting the validity of the subdividing functional dyspepsia into PDS and EPS are lacking. This article is intended to review the validity of the Rome III criteria on the subdivisions of functional dyspepsia, i.e. PDS and EPS. The impact of sleep disorder, Helicobacter pylori-associated dyspepsia, and the emerging drug therapies in functional dyspepsia will also be discussed in this article.

Association of genetic variants in GNβ3 with functional dyspepsia: a meta-analysis

BACKGROUND

Functional dyspepsia (FD) is a functional upper gastrointestinal disorder. The etiology and pathogenesis of FD remain unclear, with genetic factors playing an important role. Previous studies investigated the association of C825T in GNβ3 with FD, with conflicting results reported.

AIMS

The aim of this meta-analysis is to assess the association of genetic variants in GNβ3 with FD.

METHODS

We performed a systematic literature search in PubMed, Cochrane Library, Google Scholar, and Web of Knowledge, and conducted a meta-analysis to assess the association of C825T in GNβ3 with FD. For sensitivity analysis, we analyzed the association between C825T and subtypes of FD. We also performed meta-analyses separately for individual ethnic groups/countries of origin.

RESULTS

A total of eight studies met the eligibility criteria and were included in our analyses. Our meta-analysis finds no association between 825CC and FD (OR 1.19, 95% CI 0.84-1.67, p = 0.328). However, the association is significant under an additive model (OR 0.59, 95% CI 0.38-0.92, p = 0.018). Sensitivity analysis indicated a significant association of C825T with FD in participants from Korea but not in those from Japan, Europe, or the United States. We also detected a significant association of this SNP with dysmotility.

CONCLUSIONS

The genetic variant C825T in GNβ3 is significantly associated with FD under an additive model and the association is race-specific. Further studies with larger samples sizes are needed to validate our findings and to explore the potential mechanism underlying the association.

Impact of coexisting irritable bowel syndrome and non-erosive reflux disease on postprandial abdominal fullness and sleep disorders in functional dyspepsia

BACKGROUND/AIMS

The association between clinical symptoms and sleep disorders in functional dyspepsia (FD)-overlap syndrome has not been studied in detail.

METHODS

The subjects were 139 patients with FD, 14 with irritable bowel syndrome (IBS), 12 with nonerosive reflux disease (NERD), and 41 healthy volunteers. Gastric motility was evaluated with the (13)C-acetate breath test. We used Rome III criteria to evaluate upper abdominal symptoms, and Self-Rating Questionnaire for Depression (SRQ-D) scores to determine depression status. Sleep disorders were evaluated with Pittsburgh Sleep Quality Index (PSQI) scores.

RESULTS

There were no significant differences in age, body-mass index, alcohol intake, and smoking rate between patients with FD alone and those with FD-overlap syndrome. The postprandial abdominal fullness score in patients with FD-NERD-IBS was significantly greater than that in patients with FD-NERD overlap syndrome (p<0.001) or FD alone (p<0.001). The score for the feeling of hunger in patients with FD-NERD-IBS was significantly greater than that in patients with FD alone (p=0.0025), FD-NERD overlap syndrome (p=0.0088), or FD-IBS overlap syndrome (p=0.0057). The heartburn score in subjects with FD-NERD-IBS overlap syndrome was significantly greater than that in subjects with FD alone (p=0.0035) or FD-IBS overlap syndrome (p=0.0026). The Tmax in patients with FD-overlap syndrome or FD alone was significantly higher than that in healthy volunteers. The Pittsburgh Sleep Quality Index score in subjects with FD-NERD-IBS overlap syndrome was significantly greater than that in subjects with FD alone.

CONCLUSION

Symptom scores, such as those for postprandial abdominal fullness, heartburn, and the feeling of hunger, in patients with FD-overlap syndromes are significantly greater than those in patients with FD alone. Further studies are necessary to clarify whether various symptoms are related to sleep disorders in patients with FD-NERD-IBS overlap syndrome.

Sleep disorders in functional dyspepsia and future therapy

Sleep disorder is a common medical problem. Sleep disorder has been associated with several diseases, including pulmonary disease, gastroesophageal reflux disease (GERD) and fibromyalgia. Interest in sleep phenomenology and gastrointestinal functioning has recently increased, because sleep disorder causes significant morbidity, as evidenced by the increased need for general medical and mental health treatment for emotional problems. A number of studies have found an association between sleep disorders and functional gastrointestinal (GI) disorders. Although arousal from sleep serves several protective roles, such as increase in the speed of esophageal clearance and in airway refluxes to prevent aspiration, awakening from sleep unfortunately induces impairment of sleep quality. Some investigations about the relationship between psychogenic factors and gut motility are controversial. In addition, reports of alterations in gut motility during sleep have also been contradictory. We have evaluated sleep disorder in functional dyspepsia (FD) patients using Pittsburgh Sleep Quality Index (PSQI) score. In our recent data, PSQI score of FD patients was significantly higher compared to that in healthy volunteers. Another study has reported that the distribution of subjects who thought that they got enough sleep was significantly lower for the FD/irritable bowel syndrome (IBS) subjects than for control subjects. Several studies have reported that anti-acid therapy and prokinetic agents are effective for certain FD patients. In addition, previous study has reported tricyclic antidepressants (TCA) drugs are effective for some FD patients. Finally, new drug, actiamide, a muscarinic antagonist and cholinesterase inhibitor, significantly improves Postprandial Distress Syndrome (PDS) symptoms. It might be critical issues for determination of precise mechanism for functional gastrointestinal disorders to clarify the relationship between gut motility and sleep disorders.

Impact of sleep disorders, quality of life and gastric emptying in distinct subtypes of functional dyspepsia in Japan

Background/Aims

The association between clinical symptoms, gastric emptying, quality of life and sleep disorders in distinct functional dyspepsia (FD) patients has not been studied yet in detail.

Methods

We enrolled 79 FD patients (postprandial distress syndrome [PDS], n = 65; epigastric pain syndrome [EPS], n = 47; EPS-PDS overlap, n = 33) and 44 healthy volunteers. Gastric motility was evaluated. We used Rome III criteria to evaluate clinical symptoms and State-Trait Anxiety Inventory (STAI) scores to determine anxiety status. Sleep disorder was evaluated using the Pittsburgh Sleep Quality Index scores.

Results

There were no significant differences in age, sex and Helicobacter pylori positivity between FD subtypes and healthy volunteers. The scores of Glasgow dyspepsia severity scores (GDSS), SF-8 and Pittsburgh Sleep Quality Index (PSQI) in distinct subtypes of FD patients were significantly different from those in healthy volunteers. However, there were not significant differences in these scores, Tmax and T_1/2 among 3 subtypes of FD patients. PSQI score was significantly (P = 0.027, P = 0.002 and P = 0.039, respectively) associated with GDSS among EPS, PDS and EPS-PDS overlap patients. In addition, 8-item short form health survey (SF-8; Physical Component Score and Mental Component Score) was significantly associated with global PSQI score in PDS and EPS-PDS overlap patients. In contrast, SF-8 (Mental Component Score) only was significantly linked to global PSQI score in EPS patients.

Conclusions

Prevalences for sleep disorders, gastric motility and quality of life in 3 subtypes of FD patients were similar levels. In PDS and EPS-PDS overlap patients, SF-8 was significantly associated with global PSQI score.

Impact of sleep disorders in Japanese patients with functional dyspepsia (FD): nizatidine improves clinical symptoms, gastric emptying and sleep disorders in FD patients

BACKGROUND AND AIMS

The association between functional dyspepsia (FD) and sleep disorders has yet to be studied in detail. The aim of this study is to evaluate the risk factors associated with sleep disorders and the clinical response to nizatidine therapy for sleep disorders in Rome III-based FD patients.

METHODS

We enrolled 94 FD patients and 52 healthy volunteers. We used Rome III criteria to evaluate upper abdominal symptoms, and the Self-Rating Questionnaire for Depression scores to determine depression status. Sleep disorder was evaluated using Pittsburgh Sleep Quality Index (PSQI) scores, and degree of anxiety by the State-Trait Anxiety Inventory. Gastric motility was evaluated. Thirty-four FD patients were treated with nizatidine (300 mg/day) or placebo for 4 weeks in a crossover trial. The primary end point of this study was to determine whether nizatidine could improve clinical symptoms and sleep disorders in FD patients.

RESULTS

The global PSQI score for FD patients was significantly (P < 0.001) higher compared with healthy volunteers. There were significant correlations between global PSQI scores and total Gastrointestinal Symptom Rating Scale and Self-Rating Questionnaire for Depression scores (P < 0.001, P < 0.0001, respectively) in FD patients than in healthy volunteers. We found significant relationships between subjective sleep quality and both Tmax and T1/2 values in FD patients. Nizatidine significantly improved certain clinical symptoms, gastric emptying, and global PSQI score compared with placebo treatment.

CONCLUSION

Sleep disorders in FD patients correlated significantly with both clinical symptoms of dyspepsia and depression compared with healthy volunteers. Nizatidine significantly improved gastroesophageal reflux symptoms, gastric emptying, and sleep disorders in FD patients.

Overlap of functional dyspepsia and GERD--diagnostic and treatment implications

GERD and functional dyspepsia are the two most prevalent upper gastrointestinal disorders. Gastro-oesophageal reflux is most commonly diagnosed using the cardinal symptoms of heartburn and regurgitation. Patients might also be diagnosed using a questionnaire, after empiric treatment with an acid suppressant, after upper endoscopy or by pH testing. Functional dyspepsia is best diagnosed using symptoms outlined by the Rome committee in conjunction with a normal upper endoscopy. Theoretically, distinguishing these two populations should be easy for all health-care providers. In reality, however, carefully separating out these two populations can be quite difficult, as substantial overlap exists epidemiologically, symptomatically and even diagnostically. This overlap renders precise diagnosis a challenge; given the limited treatment options, the primary goal is to identify those patients who will respond to acid suppressive therapy. Despite the frequency with which functional dyspepsia and GERD overlap, remarkably few studies have investigated this overlap. Most recommendations are based on data derived from separate studies of functional dyspepsia and GERD. A further limitation of existing studies is their failure to differentiate between the various diagnostic categories into which the individual presenting with heartburn might belong.

Functional dyspepsia--symptoms, definitions and validity of the Rome III criteria

Dyspepsia refers to a heterogeneous group of symptoms that are localized in the epigastric region. Typical dyspeptic symptoms include postprandial fullness, early satiation, epigastric pain and epigastric burning, but other upper gastrointestinal symptoms such as nausea, belching or abdominal bloating often occur. Functional dyspepsia is defined as the presence of dyspeptic symptoms in the absence of an organic cause that readily explains them. The Rome III consensus proposed the subdivision of functional dyspepsia into postprandial distress syndrome (PDS), characterized by postprandial fullness and early satiation, and epigastric pain syndrome (EPS), characterized by epigastric pain or burning. Epidemiological studies in the USA and Europe confirmed the presence of both subgroups, with good separation between EPS and PDS. By contrast, other studies have found major overlap between EPS and PDS in patients with functional dyspepsia in specialist care centres in Europe and Asia. Preliminary pathophysiological studies suggest that PDS might be characterized by a higher prevalence of impaired gastric accommodation than EPS and raised duodenal eosinophil counts. Whether different treatment approaches are needed for EPS and PDS is currently unclear; only acotiamide, a new drug for the treatment of functional dyspepsia, has been found to be efficacious in PDS but not in EPS. Further randomized controlled trials testing treatment response by subgroup are urgently needed.

The preproghrelin 3056 TT genotype is associated with the feeling of hunger and low acylated ghrelin levels in Japanese patients with Helicobacter pylori-negative functional dyspepsia

OBJECTIVE

An impairment of gastric motility is strongly associated with the pathophysiology of functional dyspepsia (FD). Plasma ghrelin is one of the key molecules linked to gastric motility. Therefore, this study aimed to evaluate whether ghrelin (GHRL) gene polymorphisms are associated with clinical symptoms, the plasma ghrelin levels and gastric emptying in patients with FD as defined by the Rome III classification.

METHODS

We enrolled 74 Helicobacter pylori-negative patients presenting with typical symptoms of FD (epigastric pain syndrome (EPS), n=23; postprandial distress syndrome (PDS), n=51) and 102 healthy volunteers. Gastric motility was evaluated according to the Tmax value and T1/2 using the (13)C-acetate breath test. We used the Rome III criteria to evaluate upper abdominal symptoms and SRQ-D scores to determine the depression status. The Arg51Gln(346G->A), preproghrelin3056T->C, Leu72Met(408C->A) and Gln90Leu(3412T->A) polymorphisms were analyzed in DNA in blood samples obtained from the enrolled subjects. Genotyping was performed using polymerase chain reaction.

RESULTS

There was a significant relationship (p=0.048) between the preproghrelin 3056TT genotype and the serum levels of acylated ghrelin in the H. pylori-negative FD patients. The preproghrelin 3056TT genotype was significantly (p=0.047) associated with the feeling of hunger in the H. pylori-negative FD patients.

CONCLUSION

The preproghrelin 3056TT genotype is significantly associated with the acylated ghrelin levels and the feeling of hunger in H. pylori-negative FD patients. Further studies are needed to clarify the association between the preproghrelin 3056TT genotype and lower plasma acylated ghrelin levels and the impact of this relationship on the feeling of hunger in H. pylori-negative FD patients.

Pathophysiology of functional dyspepsia

Functional dyspepsia is a highly prevalent and heterogeneous disorder. Functional dyspepsia involves many pathogenic factors, such as gastric motility disorders, visceral hypersensitivity, psychological factors, Helicobacter pylori infection, and excessive gastric acid secretion. The present article provides an overview of pathogenetic factors and pathophysiologic mechanisms.