Functional dyspepsia symptoms, gastric emptying and satiety provocative test: analysis of relationships

Scintigraphy of Gastrointestinal Motility: Best Practices in Assessment of Gastric and Bowel Transit in Adults

Various radiologic examinations and other diagnostic tools exist for evaluating gastrointestinal diseases. When symptoms of gastrointestinal disease persist and no underlying anatomic or structural abnormality is identified, the diagnosis of functional gastrointestinal disorder is frequently applied. Given its physiologic and quantitative nature, scintigraphy often plays a central role in the diagnosis and treatment of patients with suspected functional gastrointestinal disorder. Most frequently, after functional gallbladder disease is excluded, gastric emptying scintigraphy (GES) is considered the next step in evaluating patients with suspected gastric motility disorder who present with upper gastrointestinal symptoms such as dyspepsia or bloating. GES is the standard modality for detecting delayed gastric emptying (gastroparesis) and the less commonly encountered clinical entity, gastric dumping syndrome. Additionally, GES can be used to assess abnormalities of intragastric distribution, suggesting specific disorders such as impaired fundal accommodation or antral dysfunction, as well as to evaluate gastric emptying of liquid. More recently, scintigraphic examinations for evaluating small bowel and large bowel transit have been developed and validated for routine diagnostic use. These can be performed individually or as part of a comprehensive whole-gut transit evaluation. Such scintigraphic examinations are of particular importance because clinical assessment of suspected functional gastrointestinal disorder frequently fails to accurately localize the site of disease, and those patients may have motility disorders involving multiple portions of the gastrointestinal tract. The authors comprehensively review the current practice of gastrointestinal transit scintigraphy, with diseases and best imaging practices illustrated by means of case review. ©RSNA, 2024 See the invited commentary by Maurer and Parkman in this issue.

How Effective Is Drinking Natural Mineral Water against Heartburn from Functional Dyspepsia, Gastroesophageal Reflux Disease, or Other Causes? A Systematic Review of Clinical Intervention Studies

BACKGROUND

For centuries, spring and other natural waters have been recommended as external or internal remedies for numerous diseases. For studies that examined the effects of drinking mineral waters against heartburn, gastroesophageal reflux disease (GERD), or functional dyspepsia, a systematic review is lacking.

OBJECTIVES

The main aim of this systematic review was to examine the effects of drinking natural mineral waters on heartburn from various causes by identifying all published intervention studies and critically appraising their methods as well as summarizing their results.

METHODS

We systematically searched the largest medical literature database MEDLINE, further relevant web sources, and gray literature for randomized and nonrandomized trials, with or without control groups, up to September 2021 and no language restrictions. Further inclusion criteria were adult patients with heartburn, drinking cure with natural mineral water as the intervention, compared to no or other interventions (care-as-usual, waiting list). We defined the reduction of heartburn symptoms and duration of disease episodes as primary and quality of life as secondary outcomes. Two reviewers independently carried out the study quality assessments (risk of bias) using the National Institutes of Health-Study Quality Assessment Tools.

RESULTS

Nine trials comprising 393 patients from Italy, Russia, Ukraine, and Germany fulfilled all inclusion criteria. We identified three randomized controlled trials (all with poor methodological quality), plus six before-after (pre/post) intervention studies without a control group. The intervention groups of the three comparative trials seemed to show a stronger reduction of self-reported heartburn symptoms, and duration of heartburn episodes than the respective control groups; however, they all had poor methodological quality.

CONCLUSION

Based on the best available evidence of clinical studies, we cannot recommend or advise against drinking natural mineral waters as a treatment for heartburn. The potential benefits of natural mineral waters that were reported in some studies with a lower evidence level (e.g., lacking a control group) should be verified by good quality randomized clinical trials with adequate comparison groups and longer follow-up periods.

Hintergrund

Seit Jahrhunderten werden Quell- und andere natürliche Wässer als äußerliche oder innerliche Heilmittel für zahlreiche Krankheiten empfohlen. Für Studien, die die Wirkung des Trinkens von Mineralwasser gegen Sodbrennen, gastroösophageale Refluxkrankheit (GERD) oder funktionelle Dyspepsie untersuchten, fehlt eine systematische Übersicht.

Zielsetzung

Das Hauptziel dieser systematischen Übersichtsarbeit war es, die Auswirkungen von Trinkkuren mit natürlichen Mineralwässern auf Sodbrennen verschiedener Ursachen zu untersuchen, indem alle veröffentlichten Interventionsstudien identifiziert und ihre Methoden kritisch bewertet sowie ihre Ergebnisse zusammengefasst wurden.

Methoden

Wir durchsuchten systematisch die größte medizinische Literaturdatenbank MEDLINE, weitere relevante Internetquellen und graue Literatur nach randomisierten und nicht-randomisierten Studien, mit oder ohne Kontrollgruppen, bis September 2021 und ohne sprachliche Einschränkungen. Weitere Einschlusskriterien waren erwachsene Patienten mit Sodbrennen, Trinkkur mit natürlichem Mineralwasser als Intervention, im Vergleich zu keiner oder anderen Interventionen (care-as-usual, Warteliste). Wir definierten die Abnahme der Symptome des Sodbrennens und die Dauer der Krankheitsepisoden als primäre und die Lebensqualität als sekundäre Endpunkte. Zwei Gutachter bewerteten unabhängig voneinander die Qualität der Studien (Verzerrungsrisiko) anhand der National Institutes of Health-Study Quality Assessment Tools.

Ergebnisse

Neun Studien mit 393 Patienten aus Italien, Russland, der Ukraine und Deutschland erfüllten alle Einschlusskriterien. Wir identifizierten drei randomisierte kontrollierte Studien (alle mit schlechter methodischer Qualität) sowie sechs Vorher-Nachher-Studien (Prä-/Post-Studien) ohne Kontrollgruppe. Die Interventionsgruppen der drei randomisierten Vergleichsstudien schienen eine stärkere Verringerung der selbstberichteten Symptome und der Dauer der Episoden des Sodbrennens zu zeigen als die jeweiligen Kontrollgruppen, allerdings waren sie alle von schlechter methodischer Qualität.

Schlussfolgerung

Auf der Grundlage der besten verfügbaren Belege aus klinischen Studien können wir das Trinken natürlicher Mineralwässer zur Behandlung von Sodbrennen weder empfehlen noch davon abraten. Die potenziellen Vorteile natürlicher Mineralwässer, die in einigen Studien mit geringerer Evidenz (z. B. ohne Kontrollgruppe) berichtet wurden, sollten durch qualitativ hochwertige randomisierte klinische Studien mit angemessenen Vergleichsgruppen und längeren Nachbeobachtungszeiträumen überprüft werden.

The herbal preparation, STW5-II, reduces proximal gastric tone and stimulates antral pressures in healthy humans

BACKGROUND

The herbal preparation, STW5-II, improves upper gastrointestinal symptoms, including abdominal fullness, early satiation, and epigastric pain, in patients with functional dyspepsia, and in preclinical models decreases fundic tone and increases antral contractility. The effects of STW5-II on esophago-gastric junction pressure, proximal gastric tone and antropyloroduodenal pressures, disturbances of which may contribute to symptoms associated with disorders of gut-brain interaction, including functional dyspepsia, in humans, have, hitherto, not been evaluated.

METHODS

STW5-II or placebo (matched for color, aroma, and alcohol content) were each administered orally, at the recommended dose (20 drops), to healthy male and female volunteers (age: 27 ± 1 years) in a double-blind, randomized fashion, on two separate occasions, separated by 3-7 days, to evaluate effects on (i) esophago-gastric junction pressures following a standardized meal using solid-state high-resolution manometry (part 1, n = 16), (ii) proximal gastric volume using a barostat (part 2, n = 16), and (iii) antropyloroduodenal pressures assessed by high-resolution manometry (part 3, n = 18), for 120 min (part 1) or 180 min (parts 2, 3).

KEY RESULTS

STW5-II increased maximum intrabag volume (ml; STW5-II: 340 ± 38, placebo: 251 ± 30; p = 0.007) and intrabag volume between t = 120 and 180 min (p = 0.011), and the motility index of antral pressure waves between t = 60 and 120 min (p = 0.032), but had no effect on esophago-gastric junction, pyloric, or duodenal pressures.

CONCLUSIONS & INFERENCES

STW5-II has marked region-specific effects on gastric motility in humans, which may contribute to its therapeutic efficacy in functional dyspepsia.

Milk coagulation and gastric emptying in women experiencing gastrointestinal symptoms after ingestion of cow's milk

BACKGROUND

Gastrointestinal symptoms after drinking milk are often attributed to lactose intolerance or cow's milk allergy. However, some individuals without either condition still report gastrointestinal symptoms after drinking milk. This may be caused by gastric emptying (GE) rate or gastric protein coagulation. This study aimed to compare GE rate and protein coagulation after milk consumption between individuals reporting gastrointestinal symptoms and those without symptoms using a novel gastric MRI approach.

METHODS

Thirty women were included in this case-control study, of whom 15 reported gastrointestinal symptoms after drinking milk and 15 were controls. Participants underwent gastric MRI before and up to 90 min after consumption of 250 mL cow's milk. Gastric content volume and image texture of the stomach contents were used to determine GE and changes in the degree of coagulation.

KEY RESULTS

GE half-time did not differ between the groups (gastrointestinal symptom group 66 ± 18 min; control group 61 ± 14 min, p = 0.845). The gastrointestinal symptom group reported symptoms from 30 min onwards and rated pain highest at 90 min. The control group reported no symptoms. Image texture analyses showed a significantly higher percentage of coagulum and lower percentage of liquid in the group in the GI symptom group (MD 11%, 95% CI [3.9, 17], p = 0.003). In vitro data suggests that pH and proteolytic enzyme activity influence the coagulum structure.

CONCLUSIONS AND INFERENCES

Gastric milk coagulation and emptied fraction of stomach content may differ between individuals experiencing symptoms after milk consumption, possibly due to differences in pH and proteolytic enzyme activity.

Relationships among intragastric meal distribution during gastric emptying scintigraphy, water consumption during water load satiety testing, and symptoms of gastroparesis

Gastric emptying scintigraphy (GES) measures total gastric retention after a solid meal and can assess intragastric meal distribution (IMD). Water load satiety test (WLST) measures gastric capacity. Both IMD immediately after meal ingestion [ratio of proximal gastric counts after meal ingestion to total gastric counts at time 0 (IMD0)] and WLST (volume of water ingested over 5 min) are indirect measures of gastric accommodation. In this study, IMD0 and WLST were compared with each other and to symptoms of gastroparesis to gauge their clinical utility for assessing patients with symptoms of gastroparesis. Patients with symptoms of gastroparesis underwent GES to obtain gastric retention and IMD0, WLST, and filled out patient assessment of upper GI symptoms. A total of 234 patients with symptoms of gastroparesis were assessed (86 patients with diabetes, 130 idiopathic, 18 postfundoplication) and 175 (75%) delayed gastric emptying. Low IMD0 <0.568 suggesting initial rapid transit to the distal stomach was present in 8% and correlated with lower gastric retention, less heartburn, and lower volumes consumed during WLST. Low WLST volume (<238 mL) was present in 20% and associated with increased severity of early satiety, postprandial fullness, loss of appetite, and nausea. Low IMD0 is associated with less gastric retention and less heartburn. Volume of water consumed during WLST, while associated with IMD0, has associations with early satiety, postprandial fullness, loss of appetite, and nausea. Thus, IMD0 and WLST appear to overlap somewhat in their assessment of gastric physiology in adults with symptoms of gastroparesis but relate to different dyspeptic symptoms.NEW & NOTEWORTHY IMD0 and WLST were assessed for their clinical utility in assessing patients with symptoms of gastroparesis. Low IMD0 is associated with less gastric retention and less heartburn. Volume of water consumed during WLST, while associated with IMD0, has associations with early satiety, postprandial fullness, loss of appetite, and nausea. IMD0 and WLST appear to overlap somewhat in their assessment of gastric physiology in adults with symptoms of gastroparesis but relate to different dyspeptic symptoms.

Altered Vagal Signaling and Its Pathophysiological Roles in Functional Dyspepsia

The vagus nerve is crucial in the bidirectional communication between the gut and the brain. It is involved in the modulation of a variety of gut and brain functions. Human studies indicate that the descending vagal signaling from the brain is impaired in functional dyspepsia. Growing evidence indicate that the vagal signaling from gut to brain may also be altered, due to the alteration of a variety of gut signals identified in this disorder. The pathophysiological roles of vagal signaling in functional dyspepsia is still largely unknown, although some studies suggested it may contribute to reduced food intake and gastric motility, increased psychological disorders and pain sensation, nausea and vomiting. Understanding the alteration in vagal signaling and its pathophysiological roles in functional dyspepsia may provide information for new potential therapeutic treatments of this disorder. In this review, we summarize and speculate possible alterations in vagal gut-to-brain and brain-to-gut signaling and the potential pathophysiological roles in functional dyspepsia.

Early steps of an alternative test meal for gastric emptying scintigraphy

Background/Aim. Gastric emptying (GE) scintigraphy provides a physiologic and noninvasive measurement of GE. Although GE scintigraphy has been standardized, preparing a meal is still complex and not practical in daily routine. The aim of the study was to prepare a simple, practical, and easily standardizable semisolid meal and investigate its role in estimating the GE function in of rabbits. Methods. In the first part of the study (basal condition), the mixture of the macroaggregated albumin (MAA) labeled with 37 MBq (1 mCi) of technetium-99m (99mTc) and 40 g of barium sulfate (1g/mL) was applied to animals via a nasogastric catheter. A series of images (frame/min, 60 min) in the anterior and posterior projections were dynamically acquired, and the motion was corrected after the radiopharmaceutical application. A few days later, the same rabbits were scanned under the same protocol after a 1 mg atropine injection to simulate gastroparesis condition. Eleven rabbits were included according to inclusion and exclusion criteria, and a total of twenty-two imaging data sets were analyzed for quantification. Results. In the basal study, total counts of the mixture decreased from 87,800.83 ? 12,622.76 to 42,733.14 ? 6,591.53 at 30 min and to 13,684.19 ? 1,774.90 at 60 min, and these decreases were statistically significant (p = 0.003). Emptying percentages were 51.39 ? 0.78% at 30 min and 84.32 ? 1.56 at 60 min and were statistically significant (p = 0.003). After intravascular atropine sulfate injection, total counts of the mixture decreased from 84,508.78 ? 11,871.48 to 64,995.18 ? 9,298 at 30 min and to 53,507.17 ? 7,258.98 at 60 min, and these decreases were statistically significant (p = 0.003). Emptying percentages were 23.10 ? 1.11% at 30 min and 36.63 ? 1.42 at 60 min and were statistically significant (p = 0.003). The difference between basal and post-atropine sulfate gastric emptying percentage at 30th (p = 0.003) and 60th (p = 0.003) min was statistically significant. Conclusion. The meal, used in this study, is non-nutrient, fatty-free, and semisolid and is easy to prepare and administer. Due to its semisolid nature, it offers a chance to evaluate the quantification of regional and total GE as well as the separate roles of the fundus and antrum.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS AND INFERENCES

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

Nutrient Drinking Test as Biomarker in Functional Dyspepsia

INTRODUCTION

Functional dyspepsia (FD) is a prevalent condition with multifactorial pathophysiology, including impaired gastric accommodation (GA), hypersensitivity to gastric distention, and delayed gastric emptying. Drink tests (DT) have been proposed as a potential biomarker for the presence and severity of gastric sensorimotor dysfunction. Thus, we aimed to summarize the state of knowledge on different DT and their potential as a biomarker for FD.

METHODS

A PubMed and MEDLINE search was conducted for English language articles, reviews, meta-analyses, case series, and randomized controlled trials, including also published meeting abstracts.

RESULTS

Several DT have been described in literature (e.g., different type of liquid, number of calories used, pace of drinking, and subject's awareness of the amount of liquid drunk). FD patients ingest significantly less volume in the different variants of the tests. The slow nutrient ("satiety drinking") test (SDT) studies show the most consistent separation between health and FD and correlation with GA. However, sensitivity to distention may be correlated with rapid DT. SDTs were used to evaluate the effect of several pharmacological agents, often showing concordance between their effects on GA and tolerated nutrient volume. This correlation was not found mainly for agents with central actions.

DISCUSSION

An SDT is a potential diagnostic biomarker in FD, reflecting GA. Additional studies are required to confirm its role as a predictive biomarker for treatment outcome in FD.

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

Background

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

Methods

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

Results

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

Conclusions and Inferences

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

Current knowledge

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

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

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

What is new here

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

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

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

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

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

Gastroesophageal Reflux Disease-Functional Dyspepsia Overlap: Do Birds of a Feather Flock Together?

INTRODUCTION

Gastroesophageal reflux disease (GERD) and functional dyspepsia (FD) are 2 of the most prevalent upper gastrointestinal (GI) disorders in the Western world. Previous Rome definitions excluded patients with predominant heartburn from the definition of FD because they were considered to have GERD. However, more recent studies showed that heartburn and acid regurgitation are also common symptoms in patients with FD. The aim of this study is to provide an overview of the prevalence of overlap between GERD and FD, the underlying pathophysiology and implications for treatment.

METHODS

A review of the literature was performed using the PubMed database, and a meta-analysis with random effects model was completed.

RESULTS

This review showed considerable overlap between GERD and FD. A meta-analysis on the data included in this review showed 7.41% (confidence interval [CI]: 4.55%-11.84%) GERD/FD overlap in the general population, 41.15% (CI: 29.46%-53.93%) GERD with FD symptoms, and 31.32% (CI: 19.43%-46.29%) FD with GERD symptoms. Although numerous committees and consensus groups attempted to develop uniform definitions for the diagnosis of GERD and FD, various diagnostic criteria are used across studies and clinical trials (frequency, severity, and location of symptoms). Several studies showed that the overlap between GERD and FD can be explained by a shared pathophysiology, including delayed gastric emptying and disturbed gastric accommodation.

DISCUSSION

For diagnoses of GERD and FD, uniform definitions that are easy to implement in population studies, easy to interpret for physicians, and that need to be well explained to patients to avoid overestimation or underestimation of true prevalence are needed. Both GERD and FD coexist more frequently than expected, based on coincidence, suggesting a potential pathophysiological link. More research is needed to explore the common GERD/FD overlap population to identify the underlying pathophysiological mechanisms, which may lead to a more effective therapeutic approach.

A symptom severity questionnaire for patients suffering from functional gastrointestinal disorder: FGI-Checklist

BACKGROUND AND AIM

A well-validated, comprehensive checklist of functional gastrointestinal (FGI) disorder (FGID) symptom severity for tracking symptom profile changes over time is lacking. We aim to develop and validate a comprehensive symptom severity checklist for FGID.

METHODS

A 20-item scale, including both upper and lower gastrointestinal symptoms, was generated to measure the symptom severity commonly found in FGID. Patients who experienced at least monthly symptoms of FGID with negative endoscopy findings were invited to complete the FGI-Checklist, Patient Health Questionaire-9 for assessing depressive symptoms, and Patient Health Questionnaire-15 for assessing somatic symptoms at baseline. A subset of patients who met Rome III diagnostic criteria of gastroesophageal reflux disease, functional dyspepsia, and irritable bowel syndrome received medication treatment for 8-12 weeks and completed the FGI-Checklist again at a follow-up visit. Exploratory factor analysis was performed for subscales formation and psychometric properties were measured.

RESULTS

Six hundred and forty-one patients were recruited for current study and 108 (16.8%) of them completed the FGI-Checklist again at follow-up. Exploratory factor analysis identified a five-factor solution accounting for 66.8% of the total variance. The five factors are named esophageal syndrome, reflux syndrome, functional dyspepsia syndrome, nausea and vomiting syndrome, and abdominal and bowel syndrome. The FGI-Checklist total score correlated with Patient Health Questionaire-9 and Patient Health Questionnaire-15 (all P < 0.001), which demonstrated good construct validity. Good item-internal consistency was found (Cronbach's alphas: 0.69-0.87). Responsiveness for reflux syndrome subscale, functional dyspepsia syndrome subscale, and abdominal and bowel syndrome subscale after medication treatment was significant (paired-t-test: all P < 0.01).

CONCLUSION

The instrument, Checklist, is valid and reliable.

Patients with dyspepsia have impaired mucosal integrity both in the duodenum and jejunum: in vivo assessment of small bowel mucosal integrity using baseline impedance

BACKGROUND

Recent studies reported that impaired proximal duodenal mucosa, assessed by duodenal biopsy, could play an important role in the development of dyspeptic symptoms. The aims of this study were (a) to develop a method to measure "in vivo" duodenal and jejunal baseline impedance (BI) and (b) to assess small bowel mucosal integrity in patients with functional dyspepsia (FD) and healthy controls (HC).

METHODS

We recruited 16 patients with FD and 15 HC. All subjects underwent ambulatory duodeno-jejunal manometry combined with impedance (HRM/Z), BI were determined by measuring impedance immediately after the passage of nocturnal migrating motor complex (MMC) phase IIIs.

RESULTS

The number of MMC phase IIIs in FD was significantly lower than that in HC (2.6 ± 1.4 vs 4.8 ± 1.7, p < 0.001). The BI in patients was significantly lower than that in HC in D1(164.2 ± 59.8 Ω in FD and 243.1 ± 40.5 Ω in HC, p = 0.0061), D2 (191.2 ± 34.1 and 256.5 ± 91.4 Ω, p = 0.01), D3 (214.0 ± 76.9 and 278.1 ± 45.3 Ω, p = 0.009), D4 (270.8 ± 54.2 and 351.8 ± 50.2 Ω, p < 0.001), and J1 (312.2 ± 55.4 and 379.3 ± 38.3 Ω, p = 0.001).

CONCLUSIONS

This is the first study reporting the duodenal and jejunal BI in vivo. The results have shown significantly lowered BI in the proximal small intestine in patients with FD compared to HC. Furthermore it suggests that measurements of small bowel BI could be used as a biomarker for diagnosis and follow up of patients with FD.

Role of Gastric Emptying in Symptoms of Gastroparesis

The symptoms of gastroparesis, such as nausea, vomiting, postprandial fullness, early satiety and abdominal pain, frequently impair the quality of life of the affected individuals. The diagnosis of gastroparesis is made after structural etiologies are ruled out and an assessment of gastric function shows delayed gastric emptying. The role of the delay in gastric emptying in the pathogenesis of symptoms of gastroparesis has been debated, with some studies suggesting an association between delayed gastric emptying and the upper gastrointestinal symptoms, while others do not. The recent literature supports the importance of using reliable methods to assess gastric emptying, as delay in gastric emptying measured on a reliable test (4-h scintigraphy or breath test) is associated with the severity of upper gastrointestinal symptoms. In addition to measuring total gastric emptying, evaluation of regional gastric retention in the proximal and distal stomach and whole gut transit to assess small intestinal and colonic transit may provide additional useful information in patients with more generalized symptoms of gastrointestinal dysmotility.

Association between delayed gastric emptying and upper gastrointestinal symptoms: a systematic review and meta-analysis

BACKGROUND

The relationship between delayed gastric emptying and upper GI symptoms (UGI Sx) is controversial.

OBJECTIVE

To assess association between gastric emptying and UGI Sx, independent of treatment.

DESIGN

We performed a systematic review and meta-analysis of the literature from 2007 to 2017, review of references and additional papers identified by content expert. We included studies evaluating the association between gastric emptying and nausea, vomiting, early satiety/postprandial fullness, abdominal pain and bloating. Covariate analyses included optimal gastric emptying test method, gastric emptying type (breath test or scintigraphy) and patient category. Meta-regression compared the differences based on type of gastric emptying tests.

RESULTS

Systematic review included 92 gastric emptying studies (26 breath test, 62 scintigraphy, 1 ultrasound and 3 wireless motility capsule); 25 of these studies provided quantitative data for meta-analysis (15 scintigraphy studies enrolling 4056 participants and 10 breath test studies enrolling 2231 participants). Meta-regression demonstrated a significant difference between optimal and suboptimal gastric emptying test methods when comparing delayed gastric emptying with nausea and vomiting. On evaluating studies using optimal gastric emptying test methodology, there were significant associations between gastric emptying and nausea (OR 1.6, 95% CI 1.4 to 1.8), vomiting (OR 2.0, 95% CI 1.6 to 2.7), abdominal pain (OR 1.5, 95% CI 1.0 to 2.2) and early satiety/fullness (OR 1.8, 95% CI 1.2 to 2.6) for patients with UGI Sx; gastric emptying and early satiety/fullness in patients with diabetes; gastric emptying and nausea in patients with gastroparesis.

CONCLUSIONS

The systematic review and meta-analysis supports an association between optimally measured delayed gastric emptying and UGI Sx.

Nutrient drink test: A promising new tool for irritable bowel syndrome diagnosis

BACKGROUND

Irritable bowel syndrome (IBS) is a highly prevalent condition. It is diagnosed on the basis of chronic symptoms after the clinical and/or investigative exclusion of organic diseases that can cause similar symptoms. There is no reproducible non-invasive test for the diagnosis of IBS, and this raises diagnostic uncertainty among physicians and hinders acceptance of the diagnosis by patients. Functional gastrointestinal (GI) syndromes often present with overlapping upper and lower GI tract symptoms, now believed to be generated by visceral hypersensitivity. This study examines the possibility that, in IBS, a nutrient drink test (NDT) provokes GI symptoms that allow a positive differentiation of these patients from healthy subjects.

AIM

To evaluate the NDT for the diagnosis of IBS.

METHODS

This prospective case-control study compared the effect of two different nutrient drinks on GI symptoms in 10 IBS patients (patients) and 10 healthy controls (controls). The 500 kcal high nutrient drink and the low nutrient 250 kcal drink were given in randomized order on separate days. Symptoms were assessed just before and at several time points after drink ingestion. Global dyspepsia and abdominal scores were derived from individual symptom data recorded by two questionnaires designed by our group, the upper and the general GI symptom questionnaires, respectively. Psycho-social morbidity and quality of life were also formally assessed. The scores of patients and controls were compared using single factor analysis of variance test.

RESULTS

At baseline, IBS patients compared to controls had significantly higher levels of GI symptoms such as gastro-esophageal reflux (P = 0.05), abdominal pain (P = 0.001), dyspepsia (P = 0.001), diarrhea (P = 0.001), and constipation (P = 0.001) as well as higher psycho-social morbidity and lower quality of life. The very low incidence of GI symptoms reported by control subjects did not differ significantly for the two test drinks. Compared with the low nutrient drink, IBS patients with the high nutrient drink had significantly more dyspeptic symptoms at 30 (P = 0.014), 45 (P = 0.002), 60 (P = 0.001), and 120 min (P = 0.011). Dyspeptic symptoms triggered by the high nutrient drink during the first 120 min gave the best differentiation between healthy controls and patients (area under receiver operating curve of 0.915 at 45 min for the dyspepsia score). Continued symptom monitoring for 24 h did not enhance separation of patients from controls.

CONCLUSION

A high NDT merits further evaluation as a diagnostic tool for IBS.

Visceral hypersensitivity is associated with GI symptom severity in functional GI disorders: consistent findings from five different patient cohorts

OBJECTIVE

Our aim was to evaluate the association between visceral hypersensitivity and GI symptom severity in large cohorts of patients with functional GI disorder (FGID) and to adjust for psychological factors and general tendency to report symptoms.

DESIGN

We included five cohorts of patients with FGIDs (IBS or functional dyspepsia; n=1144), who had undergone visceral sensitivity testing using balloon distensions (gastric fundus, descending colon or rectum) and completed questionnaires to assess GI symptom severity, non-GI somatic symptoms, anxiety and depression. Subjects were divided into sensitivity tertiles based on pain/discomfort thresholds. GI symptom severity was compared between sensitivity tertiles in each cohort and corrected for somatisation, and anxiety and depression.

RESULTS

In all five cohorts, GI symptom severity increased gradually with increasing visceral sensitivity, with significant differences in GI symptom severity between the sensitivity tertiles (p<0.0001), with small to medium effect sizes (partial η²: 0.047-0.11). The differences between sensitivity tertiles remained significant in all cohorts after correction for anxiety and depression, and also after correction for non-GI somatic symptom reporting in all of the cohorts (p<0.05).

CONCLUSIONS

A gradual increase in GI symptom severity with increasing GI sensitivity was demonstrated in IBS and functional dyspepsia, which was consistent across several large patient groups from different countries, different methods to assess sensitivity and assessments in different parts of the GI tract. This association was independent of tendency to report symptoms or anxiety/depression comorbidity. These findings confirm that visceral hypersensitivity is a contributor to GI symptom generation in FGIDs.

Postprandial Gastrointestinal Function Differs after Acute Administration of Sourdough Compared with Brewer's Yeast Bakery Products in Healthy Adults

Background

Europeans consume large quantities of bakery products, although these are known as one of the food categories that potentially leads to postprandial symptoms (such as fullness and bloating).

Objective

The aim of this study was to evaluate the effects of sourdough baked goods on gastric emptying and gastrointestinal fermentation and symptoms in healthy people.

Methods

In a double-blind, randomized crossover study, 2 sourdough croissants (SCs) or 2 brewer's yeast croissants (BCs) were served as single meals to 17 healthy adults [9 women; age range: 18-40 y; body mass index range (in kg/m2): 18-24]. Gastric volume (GV) was evaluated by magnetic resonance to calculate gastric-emptying rate in the 3-h interval after croissant ingestion. A hydrogen breath test was performed to measure hydrogen production after SC and BC ingestion. Palatability and postprandial gastrointestinal symptoms (discomfort, nausea, fullness, and bloating) over a 4-h period after the meal were evaluated. The area under the curve (AUC) was used to evaluate the overall effects on all variables tested.

Results

The total GV AUC was reduced by 11% during the 3 h after the consumption of SCs compared with BCs (P = 0.02). Hydrogen production during the 4-h interval after ingestion of SCs was 30% lower than after BCs (P = 0.03). SCs were rated as being >2 times as palatable as BCs (P < 0.001). The overall severity of postprandial symptoms was 36% lower during the 4 h after intake of SCs compared with BCs (P = 0.05).

Conclusion

Sourdough bakery products could promote better postprandial gastrointestinal function in healthy adults and be more acceptable than those prepared with brewer's yeast. This trial was registered at www.clinicaltrials.gov as NCT03207516.

Impaired Enterohormone Response Following a Liquid Test Meal in Gastrectomized Patients

BACKGROUND

Total gastrectomy (TG) is responsible for symptoms or disturbance of alimentary status (changes in body weight, food intake per meal and frequency of meal per day) which, in turn are responsible for weight loss and malnutrition. The study evaluates the gut hormone responses in totally gastrectomized (TG) patients after a liquid meal test.

METHODS

Twenty total gastrectomized cancer-free patients (12 M, 8 F, 56.4 ± 10.2 years, BMI 21.4 ± 2.2 kg/m2) and 10 healthy volunteers (4 M, 6 F, 48.0 ± 12.7 years, BMI 26.7 ± 3.0 kg/m2 ) drank a liquid meal (1.25 kcal/mL) at the rate of 50 mL/5' min for a maximum of 30 min. Satiety score was assessed and blood sample was taken at different time points.

RESULTS

The time response course, particularly for insulin, glucose-like pepetide-1, and cholecystokinin, significantly differed between TG patients and controls.

CONCLUSIONS

Our results may help to better understand hormone responses triggered by the faster arrival of nutrients in the small bowel and to explain some post-TG symptoms.

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

BACKGROUND

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

METHODS

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

KEY RESULTS

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

CONCLUSIONS AND INTERFERENCES

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

The latent structure of the functional dyspepsia symptom complex: a taxometric analysis

OBJECTIVES

Rome III introduced a subdivision of functional dyspepsia (FD) into postprandial distress syndrome and epigastric pain syndrome, characterized by early satiation/postprandial fullness, and epigastric pain/burning, respectively. However, evidence on their degree of overlap is mixed. We aimed to investigate the latent structure of FD to test whether distinguishable symptom-based subgroups exist.

METHODS

Consecutive tertiary care Rome II FD patients completed the dyspepsia symptom severity scale. Confirmatory factor analysis (CFA) was used to compare the fit of a single factor model, a correlated three-factor model based on Rome III subgroups and a bifactor model consisting of a general FD factor and orthogonal subgroup factors. Taxometric analyses were subsequently used to investigate the latent structure of FD.

KEY RESULTS

Nine hundred and fifty-seven FD patients (71.1% women, age 41 ± 14.8) participated. In CFA, the bifactor model yielded a significantly better fit than the two other models (χ² difference tests both p < 0.001). All symptoms had significant loadings on both the general and the subgroup-specific factors (all p < 0.05). Somatization was associated with the general (r = 0.72, p < 0.01), but not the subgroup-specific factors (all r < 0.13, p > 0.05). Taxometric analyses supported a dimensional structure of FD (all CCFI<0.38).

CONCLUSIONS AND INFERENCES

We found a dimensional rather than categorical latent structure of the FD symptom complex in tertiary care. A combination of a general dyspepsia symptom reporting factor, which was associated with somatization, and symptom-specific factors reflecting the Rome III subdivision fitted the data best. This has implications for classification, pathophysiology, and treatment of FD.

Efficacy of Mirtazapine in Patients With Functional Dyspepsia and Weight Loss

BACKGROUND & AIMS

A subset of patients with functional dyspepsia (FD) present with early satiation and weight loss, for which there are no established therapeutic options. We investigated the efficacy of mirtazapine (an antidepressant and antagonist of the histamine receptor H1, the α2 adrenergic receptor, and the serotonin receptors 5-HT2C and 5-HT-3) in patients with FD and weight loss.

METHODS

We conducted a randomized, placebo-controlled pilot trial that studied 34 patients with FD (29 women; mean age, 35.9 ± 2.3 years) with weight loss >10% of original body weight (mean loss, 12.4 ± 2.3 kg) without depression or anxiety. After a run-in period, patients were randomly assigned to groups given placebo (n = 17) or mirtazapine 15 mg each day for 8 weeks (n = 17) in a double-blind manner. Subjects were evaluated during a 2-week baseline and 8-week treatment for dyspepsia symptom severity, quality of life (on the basis of the Nepean Dyspepsia Index), and gastrointestinal-specific anxiety; they were given a nutrient challenge test and weighed. Data were analyzed by using linear mixed models, followed by planned contrasts with adaptive step-down Bonferroni multiple testing correction.

RESULTS

Two patients in each group dropped out. At weeks 4 and 8, mirtazapine significantly reduced mean dyspepsia symptom severity scores compared with week 0 (P = .003 and P = .017, respectively); there was no significant reduction in the placebo group (P > .37 for weeks 4 and 8). The difference in change from week 0 between mirtazapine and placebo showed a trend with a large effect size at week 4 (P = .059) that was not significant at week 8 (P = .55). However, improvements from week 0 to weeks 4 and 8 were significantly larger in the mirtazapine group than placebo group for early satiation, quality of life, gastrointestinal-specific anxiety, weight, and nutrient tolerance (mostly with large effect sizes).

CONCLUSIONS

In a randomized, placebo-controlled trial, mirtazapine significantly improved early satiation, quality of life, gastrointestinal-specific anxiety, nutrient tolerance, and weight loss in patients with FD. ClinicalTrials.gov number: NCT01240096.

The Bitter Taste Receptor Agonist Quinine Reduces Calorie Intake and Increases the Postprandial Release of Cholecystokinin in Healthy Subjects

Background/Aims

Bitter taste receptors are expressed throughout the digestive tract. Data on animals have suggested these receptors are involved in the gut hormone release, but no data are available in humans. Our aim is to assess whether bitter agonists influence food intake and gut hormone release in healthy subjects.

Methods

Twenty healthy volunteers were enrolled in a double-blind cross-over study. On 2 different days, each subject randomly received an acid-resistant capsule containing either placebo or 18 mg of hydrochloride (HCl) quinine. After 60 minutes, all subjects were allowed to eat an ad libitum meal until satiated. Plasma samples were obtained during the experiment in order to evaluate cholecystokinin (CCK) and ghrelin levels. Each subject was screened to determine phenylthiocarbamide (PTC) tasting status.

Results

Calorie intake was significantly lower when subjects received HCl quinine than placebo (514 ± 248 vs 596 ± 286 kcal; P = 0.007). Significantly higher CCK ΔT₉₀ vs T₀ and ΔT₉₀ vs T₆₀ were found when subjects received HCl quinine than placebo (0.70 ± 0.69 vs 0.10 ± 0.86 ng/mL, P = 0.026; 0.92 ± 0.75 vs 0.50 ± 0.55 ng/mL, P = 0.033, respectively). PTC tasters ingested a significantly lower amount of calories when they received HCl quinine compared to placebo (526 ± 275 vs 659 ± 320 kcal; P = 0.005), whereas no significant differences were found for PTC non-tasters (499 ± 227 vs 519 ± 231 kcal; P = 0.525).

Conclusions

This study showed that intra-duodenal release of a bitter compound is able to significantly affect calorie intake and CCK release after a standardized meal. Our results suggest that bitter taste receptor signaling may have a crucial role in the control of food intake.

Acute Anxiety and Anxiety Disorders Are Associated With Impaired Gastric Accommodation in Patients With Functional Dyspepsia

BACKGROUND & AIMS

Functional dyspepsia (FD) is associated with impaired gastric accommodation, as well as gastric hypersensitivity, delayed emptying, and psychosocial comorbidities. In healthy people, acute anxiety impairs gastric accommodation, which is traditionally quantified as the average increase in gastric volume after a meal over 1 hour. However, this quantification approach does not address the complex time course of the gastric accommodation response to a meal. We modeled gastric accommodation in patients with FD as a function of postprandial time, to investigate whether it is associated with psychosocial factors (state anxiety, anxiety disorder, depression) and gastric sensorimotor function (sensitivity, emptying).

METHODS

We studied gastric sensorimotor function in 259 consecutive patients diagnosed with FD based on Rome II at the University Hospitals Leuven from January 2002 through February 2009. Subjects underwent a gastric barostat and breath test; psychiatric comorbidity was assessed by questionnaires. Subjects completed the State-Trait Anxiety Inventory to measure levels of state anxiety immediately before and after gastric barostat analysis. The time course of the accommodation response was analyzed using mixed models. Psychological and sensorimotor variables were added to the model as continuous (state anxiety) or dichotomous (gastric sensitivity and emptying, anxiety disorders, depression) covariates, including their interaction with the time effects.

RESULTS

In subjects with FD, delayed emptying (β = 50.3 ± 15.9; P = .002) and lower state anxiety (β = -1.7 ± 0.7; P = .012) were associated with an upward shift of the accommodation curve. There was a significant interaction between comorbid anxiety disorder and linear (β = 8.2 ± 3.5; P = .02), quadratic (β = -0.4 ± 0.1; P = .004), and cubic (β = 0.005 ± 0.002; P = .002) effects of time: patients with a comorbid anxiety disorder had significantly slower initial increases in gastric volume to a lower maximum, and a slower return to baseline, compared with patients without anxiety disorder. Depression and gastric sensitivity were not associated significantly with gastric accommodation.

CONCLUSIONS

In patients with FD, state anxiety and comorbid anxiety disorders are associated with impaired accommodation; gastric emptying also is associated with accommodation in these patients. These findings help elucidate the complex interactions between psychological processes and disorders, gastric sensorimotor dysfunction, and symptom reporting in patients with FD.

Increased cerebral cannabinoid-1 receptor availability is a stable feature of functional dyspepsia: a [F]MK-9470 PET study

BACKGROUND

Functional dyspepsia (FD) is a prevalent functional gastrointestinal disorder (FGID) defined by chronic epigastric symptoms in the absence of organic abnormalities likely to explain them. Comorbidity with mood and anxiety disorders as well as with other FGIDs and functional somatic syndrome (FSS) is high. FD is characterized by abnormal regional cerebral activity in cognitive/affective pain modulatory circuits, but it is unknown which neurotransmitter systems are involved. The authors aimed to assess and compare in vivo cerebral cannabinoid-1 (CB1) receptor availability between FD patients and age-, gender- and BMI-matched healthy controls (HC).

METHODS

Twelve FD patients and 12 matched HC were investigated using positron emission tomography (PET) with the CB1 receptor radioligand [(18)F]MK-9470. Nine of the patients received a second PET scan after a naturalistic follow-up period of 36 ± 9.6 months (range: 25.2-50.4 months).

RESULTS

FD patients had significantly higher CB1 receptor availability in the cerebral regions involved in (visceral) nociception (brainstem, insula, anterior cingulate cortex) as well as in the homeostatic and hedonic regulation of food intake [hypothalamus, (ventral) striatum] (p < 0.05 corrected for multiple testing, region of interest analysis), which persisted after a follow-up period of 36 ± 9.6 months.

CONCLUSIONS

Although these findings need replication in larger samples, they suggest that the abnormal brain activity in several of these regions, previously demonstrated in FD, may be due to a sustained endocannabinoid system dysfunction, identifying it as a potential novel target for treatment and warranting further studies to elucidate whether it is also a feature of other FGIDs or FSSs.

Rome III functional dyspepsia subdivision in PDS and EPS: recognizing postprandial symptoms reduces overlap

BACKGROUND

The Rome III consensus proposed to subdivide functional dyspepsia (FD) into two groups: meal-related dyspepsia or postprandial distress syndrome (PDS), and meal-unrelated dyspepsia or epigastric pain syndrome (EPS). However, in clinical practice, overlap between both has been reported to be as high as 50%, thereby hampering clinical applicability. Although EPS is referred to as meal-unrelated dyspepsia, relationship of symptoms to meal ingestion in this category is not formally addressed in the Rome III criteria. The aim of our study was to investigate whether taking into account the relationship of epigastric pain and nausea to meal ingestion may help to improve separation between EPS and PDS.

METHODS

Consecutive ambulatory tertiary-care patients with epigastric symptoms filled out Rome III gastro-duodenal questionnaires with supplementary questions. Those fulfilling Rome III FD criteria and a negative endoscopy were identified and subdivided into 'pure' PDS patients (i.e., meeting criteria for PDS without EPS symptoms), 'pure' EPS (i.e., meeting criteria for EPS without PDS symptoms), and overlapping PDS-EPS (i.e., symptoms of both PDS and EPS).

KEY RESULTS

Out of 1029 patients coming to endoscopy, 199 patients (73% females, 45.9 ± 1.0 years, BMI: 23.7 ± 0.35) fulfilled Rome III FD diagnostic criteria, and could be subdivided into pure PDS (69% females, 49 ± 2 years, BMI: 24.2 ± 0.61), pure EPS (59% females, 47.4 ± 2 years, BMI: 23.2 ± 0.97) and overlapping PDS-EPS (64% females, age 43 ± 5 years, BMI: 26 ± 0.46). Compared with pure EPS patients, the overlap PDS-EPS patients were characterized by a higher occurrence of postprandial epigastric pain (70% vs 31%, p < 0.0001), while the occurrence of epigastric pain in between meals was borderline (48% vs 38%, p = 0.05). In addition, the overlap PDS-EPS patients reported a higher occurrence of postprandial nausea (23% vs 0%, p < 0.0001), and bloating (79% vs 28%, p = 0.0001). When postprandial epigastric pain and postprandial nausea were considered as PDS symptoms, the 'adapted' subdivision identified 48% pure PDS, 16% pure EPS, and 36% overlapping PDS-EPS patients.

CONCLUSIONS & INFERENCES

EPS and PDS symptoms frequently coexist in FD patients, with postprandial symptoms substantially contributing to the overlap. A more rigorous linking of postprandially occurring symptoms to PDS, regardless of their qualitative nature, may improve the separation between PDS and EPS.

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.

Symptom pattern following a meal challenge test in patients with irritable bowel syndrome and healthy controls

BACKGROUND

Patients with irritable bowel syndrome (IBS) often complain of worsening of symptoms after meal intake. Meal challenge tests have previously been used to study symptoms and pathophysiology in functional dyspepsia.

OBJECTIVE

The objective of this article is to evaluate differences in gastrointestinal (GI) symptom response to a standardized meal test in IBS compared to healthy controls.

METHODS

We included 67 patients with IBS and 16 healthy controls. After an overnight fast the subjects were served breakfast (540 kcal; 36% fat, 15% proteins, 49% carbohydrates; 8.9 g fiber). They completed visual analog scales assessing severity of six GI symptoms (abdominal pain, bloating, discomfort, nausea, gas, fullness) before breakfast and every 30 minutes up to 240 minutes after breakfast. The patients also completed a questionnaire (IBS-SSS) to assess IBS symptom severity during the preceding week. The course of symptom scores over time was analyzed using mixed models.

RESULTS

The meal was well tolerated and all subjects completed the test period. In patients, significant effects of time (initial increase to a maximum, followed by a return to baseline) were found for fullness, bloating, nausea and discomfort (all p values < 0.01 for linear, quadratic and third-order effect of time). In IBS patients, an independent significant association between IBS-SSS scores and all postprandial symptoms, except for nausea, was found (all p < 0.01). In controls, a significant linear, quadratic and third-order effect of time (all p < 0.0001) was found for fullness only. The difference in time course for bloating and discomfort between IBS patients and controls was confirmed when comparing the groups directly (significant time-by-group interaction effects, all p < 0.05), but not for nausea. On average, IBS patients scored significantly higher than controls on all symptoms, except for nausea (significant main effects of group, all p < 0.05).

CONCLUSIONS

A standardized meal test seems to be a promising tool to study the symptom pattern in IBS and potentially to follow the effect of interventions.

Applying novel nutrient drink to clinical trial of functional dyspepsia

Background/Aims

The drink test has been regarded as a surrogate marker of gastric accommodation. The aims of this study were to develop a novel nutrient drink test (NDT) protocol and investigate its potential for application to a clinical trial of functional dyspepsia (FD).

Methods

A novel NDT was designed, involving drinking 125 mL of nutrient 4 times at 5-minute intervals or until maximal tolerability. Healthy volunteers and patients with FD rated their symptoms every 5 minutes for 20 minutes in a developmental study. Patients with FD were enrolled in an open trial of itopride for 4 weeks. NDT was performed before and after treatment. Improvement of integrative symptoms score during NDT after treatment for more than 50% compared with baseline was defined as responder.

Results

Total aggregate symptom scores, sum of symptom scores measured during NDT, were higher in FD patients (n = 40, 368.1 ± 245.3) than in controls (n = 19, 215.9 ± 171.2) (P = 0.018) in a developmental study. In an open trial of itopride, symptom scores measured during NDT decreased significantly at all time points after treatment in responders (n = 49), whereas did not in non-responders (n = 25). Total aggregate symptom score for NDT correlated significantly with integrative dyspeptic symptom score, sum of 8 symptom scores of NDI questionnaire, at baseline (r = 0.374, P = 0.001) and after treatment (r = 0.480, P < 0.001).

Conclusions

Our novel NDT can quantify dyspeptic symptoms and reflected therapeutic effects of itopride treatment in a clinical trial of FD patients. This NDT can be used as an effective parameter in clinical trials or drug development programs for assessing effects of novel therapies on postprandial symptoms.

Duodenal eosinophilia and early satiety in functional dyspepsia: confirmation of a positive association in an Australian cohort

BACKGROUND AND AIM

Functional dyspepsia (FD), defined by unexplained pain or discomfort centered in the upper abdomen, is common. Diagnosis and treatment of FD based on the symptom-based Rome criteria remains challenging. Recently, eosinophilia in the duodenum has been implicated in the pathophysiology of FD in adults, specifically increased eosinophils in early satiety and postprandial distress, but the association remains controversial. The aim of this study was to characterize upper gastrointestinal (GI) tract pathology, specifically duodenal eosinophilia, in an Australian cohort of patients with FD.

METHODS

Patients prospectively referred for an upper GI endoscopy (n = 55; mean age, 49.6 years; 61.8% female) were stratified to FD cases (n = 33) and controls (n = 22) using Rome II criteria. All subjects completed a validated bowel symptom questionnaire. The eosinophil count per square millimeter in the duodenal bulb (D1) and second part (D2) was assessed and Helicobacter pylori status determined by gastric histology. Associations with clinical symptoms were assessed.

RESULTS

Cases and controls were demographically similar. Duodenal eosinophilia was significantly increased in subjects experiencing early satiety (P = 0.01) and postprandial fullness (P = 0.001). This association was seen in D2 but not D1. Abdominal pain was associated with eosinophilia in both D1 (P = 0.02) and D2 (P = 0.005). Smoking was also associated with higher eosinophil counts in D2 (P = 0.007) and symptoms of early satiety (P = 0.02).

CONCLUSIONS

Duodenal eosinophilia occurs in a subset of FD. The potential role of duodenal eosinophils in FD has implications for diagnosis and therapeutic trials.

Impaired duodenal mucosal integrity and low-grade inflammation in functional dyspepsia

OBJECTIVE

Functional dyspepsia (FD) is an extremely common functional gastrointestinal disorder, the pathophysiology of which is poorly understood. We hypothesised that impaired intestinal barrier function is involved in the onset and persistence of this disorder by inducing low-grade inflammation. Therefore, our aim was to evaluate duodenal mucosal integrity and low-grade inflammation in patients with FD.

DESIGN

Duodenal biopsy specimens were obtained from 15 patients with FD fulfilling the Rome III criteria and 15 age- and gender-matched healthy volunteers. Transepithelial electrical resistance (TEER) and paracellular permeability were measured in Ussing chambers. Expression of cell-to-cell adhesion proteins was evaluated by real-time PCR, western blot and/or immunofluorescence. Numbers of mast cells, eosinophils and intraepithelial lymphocytes were assessed by immunohistochemistry.

RESULTS

Patients with FD displayed lower TEER and increased paracellular passage compared with healthy controls, which is indicative of impaired mucosal integrity. In addition, abnormal expression of cell-to-cell adhesion proteins at the level of tight junctions, adherens junctions and desmosomes was shown. Furthermore, patients were characterised by the presence of low-grade inflammation, as demonstrated by increased infiltration of mucosal mast cells and eosinophils. A significant association between the expression level of several cell-to-cell adhesion proteins, the extent of increased permeability and the severity of low-grade inflammation was found.

CONCLUSIONS

These findings challenge the classical paradigm that patients with FD show no structural changes in the gastrointestinal tract. We suggest that impaired intestinal barrier function is a pathophysiological mechanism in FD. Thus, restoration of intestinal barrier integrity may be a potential therapeutic target for treating patients with FD.

A multidimensional model of psychobiological interactions in functional dyspepsia: a structural equation modelling approach

OBJECTIVE

Gastric sensorimotor function, abuse history, 'trait' and 'state' psychological factors and 'somatisation' all play a role in functional dyspepsia (FD) and its associated impaired quality of life (QoL), but their interplay remains poorly understood. We aimed to test a comprehensive, a priori hypothesised model of interactions between these dimensions in FD.

DESIGN

In 259 FD patients, we studied gastric sensitivity with a barostat. We measured abuse history (sexual/physical, childhood/adulthood), 'trait' (alexithymia, trait anxiety) and 'state' (positive/negative affect, depression, panic disorder) psychological factors, somatic symptom reporting (somatic symptom count, dyspepsia, irritable bowel syndrome and fatigue symptoms) and QoL (physical, mental) using validated questionnaires. Confirmatory factor analysis (CFA) was used to assess whether four a priori hypothesised latent variables ('abuse', 'trait affectivity', 'state affect' and 'somatic symptom reporting') were adequately supported by the data. Structural equation modelling (SEM) was used to test the a priori hypothesised relationships between these latent variables and the observed variables gastric sensitivity and QoL.

RESULTS

Both the CFA and SEM models fitted the data adequately. Abuse exerted its effect directly on 'somatic symptom reporting', rather than indirectly through psychological factors. A reciprocal relationship between 'somatic symptom reporting' and 'state affect' was found. Gastric sensitivity influences 'somatic symptom reporting' but not vice versa. 'Somatic symptom reporting' and 'trait affectivity' are the main determinants of physical and mental QoL, respectively.

CONCLUSIONS

We present the first comprehensive model elucidating the complex interactions between multiple dimensions (gastric sensitivity, abuse history, 'state' and 'trait' psychological factors, somatic symptom reporting and QoL) in FD.

[Functional dyspepsia and the satiety test: its usefulness in clinical practice]

INTRODUCTION

According to the Rome III Criteria, functional dyspepsia (FD) is classified as postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). On the other hand, the satiety test (ST) has been used to evaluate gastric accommodation and emptying, distinguishing healthy individuals from those with dyspepsia.

AIMS

To determine whether the ST can distinguish dyspeptic individuals from healthy ones and to evaluate its usefulness in differentiating the two FD subtypes.

METHODS

Adults with FD were consecutively enrolled in a cross-sectional study within the time frame of August 2011 and October 2012. Healthy subjects participated as controls. The ST consisted of the intake of a nutritional supplement (Fortisip®, Nutricia Bagó®) at a constant speed; satiety was graded at 5-minute intervals (1 to 5 points). Intake was suspended when the maximum score was reported. The total ingested volume and caloric intake was recorded and the Mann-Whitney U test was used in the statistical analysis.

RESULTS

The study included 39 dyspeptic patients and 20 control individuals. The patients were predominantly women (84.6 vs. 25%; p < 0.0001) and they were similar in age (39.59 ± 13.53 vs. 34.70 ± 9.85 years) and BMI (24.32 ± 3.52 vs. 25.82 ± 3.34 kg/m2) with respect to the controls. The FD subtype percentages were PDS: 61%, EPS: 31%, and Mixed syndrome: 8%. There was a lower ingested volume and caloric intake on the part of the dyspeptic patients (185 vs. 300 ml and 277 vs. 520 Kcal, respectively. Both: P<.001). No differences in the ST were observed between the two pure dyspepsia subtypes.

CONCLUSIONS

There was a difference in the ST between healthy individuals and those with dyspepsia, but the ingested volume and caloric intake in the two FD subtypes were similar.

Associations between gastric sensorimotor function, depression, somatization, and symptom-based subgroups in functional gastroduodenal disorders: are all symptoms equal?

BACKGROUND

Previous work indicated that psychosocial factors (depression and somatization) are more strongly associated with symptom severity and weight loss in functional dyspepsia (FD) than gastric sensorimotor function. However, there is conflicting evidence regarding the association of these etiopathogenetic factors with Rome III symptom-based subgroups in FD [epigastric pain syndrome (EPS), postprandial distress syndrome (PDS)]. We aimed to test whether gastric sensitivity and emptying, depression, and somatization are differentially associated with empirically derived functional gastroduodenal disorders (FGD) symptom factors in one comprehensive model.

METHODS

In 259 tertiary care FD patients, we studied gastric sensorimotor function with barostat and gastric emptying breath test. Depression, somatization, and FGD symptoms were measured using self-report questionnaires. Confirmatory factor analysis (CFA) on 7 FGD symptoms was used to determine the fit of a latent variable structure based on Rome III symptom-based subgroups. Structural equation modeling (SEM) was used to test the putative relationships of the symptom factors with gastric sensorimotor function, depression, and somatization.

KEY RESULTS

The results of the CFA show a good fit [C(min) /DF = 1.54, CFI(comparative fit index) = 0.97] for the three-factor solution based on Rome III subgroups. The SEM also fitted the data well (C(min) /DF = 1.24, CFI = 0.98) and demonstrated that gastric sensitivity and depression are associated with PDS and nausea and vomiting. Gastric emptying is uniquely associated with EPS and somatization is strongly associated with all three symptom factors.

CONCLUSIONS & INFERENCES

Confirmatory factor analysis confirms the existence of three FGD symptom factors, corresponding to Rome III symptom-based subgroups. The SEM results suggest that different psychobiological mechanisms may play a role in these subgroups.

Influence of sumatriptan on gastric accommodation and on antral contraction in healthy subjects assessed by ultrasonography

BACKGROUND

Oral sumatriptan administration has been reported to delay gastric emptying after liquid meals. The aim of this study was to determine whether delayed gastric emptying is caused by enhanced gastric accommodation, impaired antral contractions, or both using ultrasonography.

METHODS

Ten healthy volunteers were enrolled in this randomized two-way crossover study. After overnight fasting, the subjects received the liquid meal 60 min after ingesting a 50 mg sumatriptan tablet with 50 mL of water or 50 mL of water alone (control). The cross-sectional area of the proximal stomach was measured in a supine position after every 100 mL. The frequency and amplitude of the antral contractions were measured in a slightly backward sitting position. The intragastric distribution of the liquid meal was assessed by calculating the proximal stomach/distal stomach ratio (prox/distal ratio).

KEY RESULTS

The cross-sectional area after drinking 100, 200, and 300 mL of the liquid meal (oral sumatriptan vs control) was 34.49 vs 15.11 cm(2) (P = 0.0051), 48.00 vs 30.61 cm(2) (P = 0.0166), and 58.67 vs 47.19 cm(2) (P = 0.0125), respectively. There was no significant difference in the amplitude of contractions, contraction cycle, motility index, and prox/distal ratio (97.15 vs 97.93%, P = 0.0745; 19.42 vs 19.5 s, P= 0.8590; and 887.58 vs 889.22, P = 0.5751; 9.75 vs 8.41, P = 0.8785; respectively).

CONCLUSIONS & INFERENCES

Oral sumatriptan administration enhanced gastric accommodation after the ingestion of liquid nutrients, but had no significant effect on antral contractions or intragastric distribution in healthy subjects.

Efficacy of buspirone, a fundus-relaxing drug, in patients with functional dyspepsia

BACKGROUND & AIMS

Impaired accommodation and hypersensitivity to gastric distention are believed to be involved in the development of functional dyspepsia (FD). Buspirone, a 5-hydroxytryptamine 1A receptor agonist, relaxes the proximal stomach in healthy individuals. We studied the effects of buspirone on symptoms and mechanisms of FD.

METHODS

We performed a randomized, double-blind, placebo-controlled, crossover study of 17 patients (13 women; mean age, 38.5 ± 2.4 years). The study included 2 treatment periods of 4 weeks each, separated by a 2-week washout period. In the first period, 7 participants were given buspirone (10 mg, 3 times daily for 4 weeks) and 10 were given placebo 15 minutes before meals; patients switched groups for the second period. We assessed meal-related symptoms and severity, along with gastric sensitivity, accommodation, and emptying (by using barostat and breath tests) before and after 4 weeks of treatment.

RESULTS

Buspirone significantly reduced the overall severity of symptoms of dyspepsia (7.5 ± 1.3 vs 11.5 ± 1.2 for placebo; P < .005) and individual symptoms of postprandial fullness, early satiation, and upper abdominal bloating, whereas placebo had no significant effect (all P < .05). Buspirone did not alter the rate of gastric emptying of solids or sensitivity to gastric distention, but it significantly increased gastric accommodation, compared with placebo (229 ± 28 vs 141 ± 32 mL, respectively; P < .05), and delayed gastric emptying of liquids (half-life = 64 ± 5 vs 119 ± 24 minutes, respectively). Adverse events were similar when patients were given buspirone or placebo.

CONCLUSIONS

In patients with FD, 4 weeks of administration of buspirone significantly improved symptoms and gastric accommodation, compared with placebo, whereas gastric emptying of liquids was delayed.

Relationship between Symptoms and Gastric Emptying of Solids in Functional Dyspepsia

Objective:

Functional dyspepsia is a heterogeneous disorder and different pathophysiological mechanisms underlie its symptom patterns. This study investigated the relationship between dyspepsia symptoms and overall and proximal gastric emptying in patients with functional dyspepsia.

Methods:

A total of 93 patients with functional dyspepsia and 32 healthy subjects were enrolled in this cross-sectional study. Prevalence and severity of eight dyspepsia symptoms were recorded. Gastric emptying was measured using single photon emission computed tomography scanning.

Results:

Overall and proximal gastric emptying were delayed in 47.3% (44/93) and 46.2% (43/93) of the patients, respectively. Logistic regression analyses showed that presence of nausea was associated with delayed proximal gastric emptying (odds ratio 4.951; 95% confidence interval 1.321, 18.558). There were no significant differences between normal and delayed overall gastric emptying according to presence of symptoms.

Conclusions:

Presence of nausea might indicate delayed gastric emptying of the proximal stomach. Promotion of proximal gastric emptying may constitute an effective therapy for patients with functional dyspepsia who report nausea as the dominant symptom.

Advancing gastric emptying studies: standardization and new parameters to assess gastric motility and function

For many years, gastric emptying (GE) studies were performed using various local protocols and different radiolabeled meals. This lack of standardization and normal values made the test results unreliable and difficult to compare from one site to another. A recent consensus has been published that now provides guidance and standardization on how to perform a radiolabeled solid-meal GE study. It is widely recognized, however, that simple measurement of total GE of a solid meal often does not provide an answer to the etiology of symptoms for a large number of patients who present with functional dyspepsia. Advances in our understanding of the different roles of the fundus and antrum and their complex interaction with the proximal small bowel and central nervous system have led to the development of new methods to study gastric motility. This review describes how a more comprehensive approach to studying GE is needed and how this will lead to better diagnosis and treatment for patients referred for GE studies.

Delayed gastric emptying rates and impaired antral motility in children fulfilling Rome III criteria for functional abdominal pain

BACKGROUND

Gastric sensorymotor dysfunctions have been implicated in the pathophysiology of some functional gastrointestinal disorders, such as functional dyspepsia and irritable bowel syndrome. Therefore, we hypothesized that abnormal gastric emptying and impaired antral motility are possible underlying mechanisms of symptoms in children with functional abdominal pain (FAP).

METHODS

Hundred and two children [37 (36.3%) males, 4-14 years, mean 7.8 years, SD 2.7 years] fulfilling Rome III criteria for FAP were recruited for this study. An age and sex compatible group of healthy children (n = 20) were selected as controls [8 (40%) males, 4-14 years, mean 8.4 years, SD 3.0 years]. Liquid gastric emptying rate (GER) and antral motility parameters (amplitude of antral contractions, frequency of antral contractions and antral motility index) were assessed using a previously reported ultrasound method.

KEY RESULTS

Average GER (42.1% vs 66.2% in controls), amplitude of antral contractions (56.5% vs 89%), frequency of contractions per 3 min (8.5 vs 9.3), and antral motility index (4.9 vs 8.3) were significantly lower in patients with FAP compared with controls (P < 0.01). Fasting antral area was higher in patients (1.4 vs 0.6, P < 0.0001). GER negatively correlated with the scores obtained for severity of abdominal pain (r = -0.29, P = 0.004).

CONCLUSIONS & INFERENCES

Gastric emptying rate and antral motility parameters were significantly impaired in patients with FAP and GER negatively correlated with symptom severity. These findings highlight the possible role of gastrointestinal motility abnormalities in the pathophysiology of childhood FAP.

The role of a pre-load beverage on gastric volume and food intake: comparison between non-caloric carbonated and non-carbonated beverage

BACKGROUND

There is conflicting data on the effects of carbon dioxide contained in beverages on stomach functions. We aimed to verify the effect of a pre-meal administration of a 300 ml non-caloric carbonated beverage (B+CO2) compared to water or a beverage without CO2 (B-CO2), during a solid (SM) and a liquid meal (LM) on: a) gastric volume, b) caloric intake, c) ghrelin and cholecystokinin (CCK) release in healthy subjects.

METHODS

After drinking the beverages (Water, B-CO2, B+CO2), ten healthy subjects (4 women, aged 22-30 years; BMI 23 ± 1) were asked to consume either an SM or an LM, at a constant rate (110 kcal/5 min). Total gastric volumes (TGV) were evaluated by Magnetic Resonance Imaging after drinking the beverage and at maximum satiety (MS). Total kcal intake at MS was evaluated. Ghrelin and CCK were measured by enzyme immunoassay until 120 min after the meal. Statistical calculations were carried out by paired T-test and analysis of variance (ANOVA). The data is expressed as mean ± SEM.

RESULTS

TGV after B+CO2 consumption was significantly higher than after B-CO2 or water (p < 0.05), but at MS, it was no different either during the SM or the LM. Total kcal intake did not differ at MS after any of the beverages tested, with either the SM (Water: 783 ± 77 kcals; B-CO2: 837 ± 66; B+CO2: 774 ± 66) or the LM (630 ± 111; 585 ± 88; 588 ± 95). Area under curve of ghrelin was significantly (p < 0.05) lower (13.8 ± 3.3 ng/ml/min) during SM following B-CO2 compared to B+CO2 and water (26.2 ± 4.5; 27.1 ± 5.1). No significant differences were found for ghrelin during LM, and for CCK during both SM and LM after all beverages.

CONCLUSIONS

The increase in gastric volume following a 300 ml pre-meal carbonated beverage did not affect food intake whether a solid or liquid meal was given. The consistency of the meal and the carbonated beverage seemed to influence ghrelin release, but were unable, under our experimental conditions, to modify food intake in terms of quantity. Further studies are needed to verify if other food and beverage combinations are able to modify satiation.

Do we have an alternative for the Rome III gastroduodenal symptom-based subgroups in functional gastroduodenal disorders? A cluster analysis approach

BACKGROUND

Functional dyspepsia (FD) is a heterogeneous biopsychosocial disorder. The Rome III consensus proposed a subdivision into epigastric pain syndrome and postprandial distress syndrome, based on gastroduodenal symptom pattern only; nausea/vomiting- and belching disorders were classified as separate functional gastroduodenal disorders (FGD). We aimed to investigate an alternative subdivision of FGD, taking into account gastric sensorimotor function, anxiety & depression and 'somatization', besides gastroduodenal symptoms.

METHODS

Gastroduodenal symptom data were available for 857 consecutive FGD patients (Rome II criteria). In a subsample (n=259), additional data were obtained on gastric sensitivity, anxiety, depression and 'somatization'. Two separate cluster analyses were performed. In analysis 1, clustering was based on individual gastroduodenal symptom scores. In analysis 2, gastric sensitivity, anxiety & depression and 'somatization', besides total gastroduodenal symptoms score, were used for clustering.

KEY RESULTS

Analysis 1 identified four clusters, largely supporting the Rome III classification, with early satiation, pain and nausea/vomiting clusters, besides a limited severity cluster (R(2) = 0.32). Analysis 2 suggested a five-cluster solution (R(2) = 0.48). Anxiety, depression and 'somatization' were the most important variables separating the clusters. 'Primary somatization' (with low psychiatric symptom levels) as well as 'secondary somatization' (with high anxiety & depression scores) subgroups were identified, besides three other subgroups characterized by psychiatric/gastroduodenal symptoms, mild anxiety symptoms and limited overall severity, respectively.

CONCLUSIONS & INFERENCES

We propose an alternative to the current subgrouping in FGD that is exclusively based on gastroduodenal symptoms. This may have consequences for future classification of FGD, as well as broader relevance towards the debate on subgrouping 'functional somatic syndromes'.

Long-term Ultrasonographic Follow-up Study of Gastric Motility in Patients with Functional Dyspepsia

Although patients with functional dyspepsia complain of epigastric symptoms, the relation between these symptoms and gastric motility remains controversial. There are few reports on the clinical course of functional dyspepsia, including changes in gastric motility, observed over a considerably long period. We conducted a study to examine association between changes in symptoms and changes in ultrasonographically evaluated gastric motility over a long-term follow-up period in patients with functional dyspepsia. Forty patients (18 men, 22 women; mean age, 53.7 years) with functional dyspepsia were followed up by medical interview, physical examination, endoscopy, and ultrasonography for gastric motility. Follow-up ranged from 1.0 to 7.8 years (mean, 3.0 years). Ultrasonographic evaluation of gastric motility included gastric emptying rate and antral contractions. During the follow-up period, patients were treated with proton pump inhibitors, H2-blockers, or prokinetics. Symptoms improved in 21 patients (group A), but symptoms persisted or worsened in 19 patients (group B). There were no significant differences in clinical characteristics between the two groups. Gastric motility improved in group A but not in group B. In conclusion, improved gastric motility appears to correspond to and may explain improved symptoms in some patients with functional dyspepsia.

Factors associated with co-morbid irritable bowel syndrome and chronic fatigue-like symptoms in functional dyspepsia

BACKGROUND

It is unclear which factors explain the high co-morbidity between functional dyspepsia (FD) and other functional somatic syndromes. The aim of this study is to investigate the association between gastric sensorimotor function, psychosocial factors and 'somatization' on the one hand, and co-morbid irritable bowel syndrome (IBS) and chronic fatigue (CF)-like symptoms on the other, in FD.

METHODS

In 259 tertiary care FD patients, we studied gastric sensorimotor function with barostat (sensitivity, accommodation). We measured psychosocial factors (abuse history, alexithymia, trait anxiety, depression, panic disorder) and 'somatization' using self-report questionnaires, and presence of IBS and CF-like symptoms. Hierarchical multiple logistic regression was used to determine which of these factors were independently associated with co-morbid IBS and CF-like symptoms, including testing of potential mediator effects.

KEY RESULTS

Co-morbid IBS or CF-like symptoms respectively were found in 142 (56.8%) and 102 (39.4%) patients; both co-morbidities were not significantly associated (P=0.27). Gastric accommodation (β=0.003, P=0.04) and 'somatization' (β=0.17, P= 0.0003) were independent risk factors for IBS (c=0.74, P<0.0001); the effect of adult abuse (β=0.72, P=0.20) was mediated by 'somatization'. Depression (β=0.16, P=0.008) and 'somatization' (β=0.18, P=0.004) were overlapping risk factors for CF-like symptoms (c=0.83, P<0.0001); the effects of alexithymia and lifetime abuse were mediated by depression and 'somatization', respectively.

CONCLUSIONS & INFERENCES

'Somatization' is a common risk factor for co-morbid IBS and CF-like symptoms in FD and mediates the effect of abuse. Gastric sensorimotor function and depression are specific risk factors for co-morbid IBS and CF-like symptoms, respectively.

Longitudinal and cross-sectional factors associated with long-term clinical course in functional dyspepsia: a 5-year follow-up study

OBJECTIVES

Functional dyspepsia (FD) is a heterogeneous disorder with different pathophysiological mechanisms underlying the symptom pattern, but little is known about its clinical course. The aims of this study were to study the long-term evolution of symptoms in a clinical FD population and to identify factors associated with outcome.

METHODS

FD patients who previously underwent gastric function testing and filled out a dyspepsia symptom score (DSS) were contacted. At follow-up, patients indicated whether symptoms had worsened, remained unchanged, improved, or disappeared. Anxiety and depression, DSS, chronic fatigue symptoms, irritable bowel syndrome (IBS) comorbidity, and FD-specific quality of life (QoL) were assessed using mailed questionnaires. Bivariate associations between different patient characteristics and DSS and QoL at follow-up were tested; multiple linear regression was used to identify factors associated with the outcomes, both longitudinally and cross-sectionally.

RESULTS

Data were obtained from 253 patients (84.9% of the eligible and consenting population (n=298) and 53.2% of the original population (n=476)). The mean duration of follow-up was 68±2 months. Disappeared, improved, unchanged, and worsened symptoms were reported by 17.4, 38.3, 30.8, and 13.4% of the patients, respectively. Correlations between dyspepsia symptoms at initial visit and follow-up were small to moderate in magnitude. DSS at initial visit and trait anxiety were longitudinally associated with DSS at follow-up, with a trend found for weight loss; depression, chronic fatigue, and IBS at follow-up were cross-sectionally associated with DSS. Trait anxiety, weight loss, and DSS at initial visit were independently associated with QoL at follow-up; depression as well as DSS and chronic fatigue at follow-up were cross-sectionally associated.

CONCLUSIONS

About half of FD patients reported disappeared or improved symptoms after a mean follow-up of 5 years. Although stability of symptom levels is low to moderate, DSS at initial visit, trait anxiety, and initial weight loss are more strongly associated with outcome than gastric sensorimotor function.

Risk factors for impaired health-related quality of life in functional dyspepsia

BACKGROUND

The influence of patient characteristics on HRQoL in functional dyspepsia is poorly understood.

AIM

To determine the contribution of gastric sensorimotor function, psychosocial factors & 'somatization' to HRQoL in functional dyspepsia.

METHODS

In 259 tertiary care functional dyspepsia patients, we studied gastric sensorimotor function with barostat. We measured psychosocial factors and 'somatization' using self-report questionnaires. HRQoL was assessed using the SF-36 physical and mental composite scores (PCS, MCS). Bivariate associations between gastric sensorimotor function, psychosocial factors and 'somatization' on the one hand and PCS and MCS on the other were estimated. Variables significantly associated with PCS or MCS in bivariate analysis were entered into hierarchical multiple linear regression models.

RESULTS

Mean PCS was 40.1 ± 9.5; mean MCS was 45.1 ± 10.8. 'Somatization' (P < 0.0001) and chronic fatigue (P = 0.002) were significantly associated with impaired PCS (R² = 0.52, P < 0.0001). The effects of abuse history and depression were 'mediated' by 'somatization'. Trait anxiety (P = 0.02), alexithymia (P = 0.06), depression (P = 0.06), positive affect (P < 0.0001), negative affect (P = 0.002) and generalised anxiety disorder (P = 0.01) were significantly associated with impaired MCS (R² = 0.67, P < 0.0001).

CONCLUSIONS

'Somatization' is the most important risk factor for impaired physical HRQoL in functional dyspepsia; it 'mediates' the effect of abuse history and depression. Mental HRQoL is mainly explained by psychosocial factors.

New frontiers in gut nutrient sensor research: monosodium L-glutamate added to a high-energy, high-protein liquid diet promotes gastric emptying: a possible therapy for patients with functional dyspepsia

Functional dyspepsia is a clinical syndrome that features abdominal symptoms centered in the upper abdomen without an organic basis. Three possible mechanisms of gastric dysfunction could be related to functional dyspepsia: 1) delayed gastric emptying, 2) impaired gastric accommodation to food intake, and 3) hypersensitivity to gastric distention. Delayed gastric emptying has been suggested to lead to prolonged antral distension that causes dyspeptic symptoms. Delayed gastric emptying is therefore a focal point of debate about anorexia caused by dyspepsia, and prokinetic agents are often administered in Japan for its treatment. Recently, we found that addition of monosodium L-glutamate (MSG) to a high-energy liquid diet rich in casein promoted gastric emptying in healthy men. Therefore, another potential method to improve delayed gastric emptying could be enhancement of chemosensors that activate the autonomic nervous system innervating the gastrointestinal tract. In conclusion, enrichment with glutamate promoted gastric emptying after intake of a high-protein meal, suggesting that free glutamate is important for protein digestion and that MSG may be helpful for management of delayed gastric emptying in patients with functional dyspepsia.

Symptom pattern and pathophysiological correlates of weight loss in tertiary-referred functional dyspepsia

In patients with gastrointestinal symptoms, weight loss is an alarm symptom, indicative of organic disease. Recent studies reported weight loss in subsets of functional dyspepsia (FD) patients. The aim of this study was to analyse symptom patterns associated with weight loss in tertiary care FD. Six hundred and thirty-six FD patients (67% female, mean age 43 years) completed a dyspepsia questionnaire, and underwent gastric emptying and gastric barostat studies. After identifying independent symptom domains through orthogonal factor analysis, patients were clustered on the basis of symptom profile. Clusters were compared in terms of their association with weight loss and gastric emptying or sensorimotor function. Weight loss (4.2 kg on average) correlated most strongly with early satiety followed by nausea and vomiting (rho respectively 0.38, 0.28 and 0.23, all P < 0.0001). Factor analysis revealed three factors: Factor 1 characterized by nausea, vomiting and early satiety; factor 2 by early satiety, postprandial fullness and bloating; and factor 3 by pain, epigastric burning and belching. Subsequent cluster analysis revealed six patient clusters. The most severe cluster, which loaded high on all three factors, and a cluster dominated factor 2 were associated with the highest average weight loss (6.8 and 8.0 kg, respectively). The former cluster was also characterized by visceral hypersensitivity and delayed gastric emptying. The lowest weight loss occurred in the two clusters that had depressed scores for both early satiety associated factors (2.4 and 2.5 kg, respectively). In tertiary care FD, weight loss is strongly associated with two early satiety associated symptom clusters.