Childhood abuse history is associated with the development of dyspepsia: a population-based survey in Japan

Breaking Barriers in Functional Dyspepsia: A Systematic Review and Meta-analysis on Duodenal Tight Junction Protein Expression

Background/Aims

Disruptions in tight junction (TJ) protein expression leading to duodenal epithelial barrier impairment may contribute to increased intestinal permeability, potentially playing a role in functional dyspepsia (FD) pathophysiology. Currently published studies evaluated the role of several TJ proteins in FD patients with inconsistent results. Therefore, we conducted this systematic review and metaanalysis to evaluate the duodenal mucosal expression of several TJ proteins in FD.

Methods

We performed a systematic electronic search on PubMed, EMBASE, and Scopus using predefined keywords. Diagnosis of FD by Rome III or Rome IV criteria was considered acceptable. Full articles satisfying our inclusion and exclusion criteria were included. The principal summary outcome was the mean difference of several TJ proteins in FD patients and control subjects.

Results

A total of 8 and 5 studies were included in our qualitative and quantitative synthesis, respectively, with a total population of 666 participants, out of which 420 were FD patients. No significant differences were observed between FD patients and controls in the expression of claudin-1 (-0.102 [95% CI, -0.303, 0.099]), claudin-2 (0.161 [95% CI, -0.134, 0.456)], claudin-3 (0.278 [95% CI, -0.280, 0.837]), claudin-4 (0.045 [95% CI, -0.264, 0.354]), ZO-1 (-0.221 [95% CI, -0.683, 0.241]), ZO-2 (-0.070 [95% CI, -0.147, 0.007]), ZO-3 (-0.129 [95% CI, -0.376, 0.118]), β-catenin (-0.135 [95% CI, -0.484, 0.214]), E-cadherin (-0.083 [95% CI, -0.229, 0.063]), and occludin (-0.158 [95% CI, -0.409, 0.093]).

Conclusions

The expressions of all evaluated proteins including claudin-1, claudin-2, claudin-3, claudin-4, ZO-1, ZO-2, ZO-3, β-catenin, E-cadherin, and occludin did not significantly differ between FD patients and controls. However, due to the limited number of included studies, results should be interpreted with caution.

Factors Predicting Effectiveness of Eradication Therapy for Helicobacter pylori-Associated Dyspepsia Symptoms

Functional dyspepsia is distinguishable from Helicobacter pylori-associated dyspepsia. However, distinguishing H. pylori-associated dyspepsia from functional dyspepsia before H. pylori eradication is difficult. Therefore, in the present study, we aimed to investigate whether serum pepsinogen levels before H. pylori eradication are associated with the amelioration of dyspepsia after successful H. pylori eradication. Additionally, we examined the usefulness of serum pepsinogen levels and other factors in predicting dyspepsia outcomes. H. pylori eradication was effective in 14 patients (Responders) and ineffective in 19 patients (Non-responders). The pepsinogen I/II ratio in Responders (3.4 ± 1.2) and Non-responders (2.3 ± 1.0) differed significantly (p = 0.006). The optimal cut-off pepsinogen I/II value was 2.3. Multivariate logistic regression analysis showed that the adjusted odds ratio for Non-responders was 26.1 (95% confidence interval: 2.0-338.0, p = 0.012) for a pepsinogen I/II ratio ≤ 2.3 and 8.10 (95% confidence interval: 1.1-57.6, p = 0.037) for smoking habits. The pepsinogen I/II ratio and smoking habits were associated with the effects of H. pylori eradication on dyspeptic symptoms. Thus, the pepsinogen I/II ratio cut-off value can be used to identify patients likely to respond to H. pylori eradication after the resolution of dyspeptic symptoms.

Functional Dyspepsia: Current Understanding and Future Perspective

BACKGROUND

Functional dyspepsia (FD) is a common disorder characterized by chronic or recurrent upper abdominal pain or discomfort without any structural abnormalities in the gastrointestinal tract. FD is categorized into two subgroups based on symptoms: postprandial distress syndrome (PDS) and epigastric pain syndrome.

SUMMARY

The pathophysiology of FD involves several mechanisms. Delayed gastric emptying is observed in approximately 30% of FD patients but does not correlate with symptom patterns or severity. Impaired gastric accommodation is important in the pathophysiology, particularly for PDS. Visceral hypersensitivity, characterized by heightened sensitivity to normal activities, contributes to the perception of discomfort or pain in FD. Alterations to the duodenal mucosa, including impaired mucosal barrier function and low-grade inflammation, are also implicated in the pathogenesis of FD. Microbial dysbiosis and psychological factors such as stress can further exacerbate symptoms. Treatment options include dietary modifications, establishing a physician-patient relationship, acid suppressants, prokinetics, neuromodulators, and behavioral therapies. Dietary recommendations include eating smaller, more frequent meals, and avoiding trigger foods. Acid suppressants are used as the first-line treatment. Prokinetics and neuromodulators aim to improve gastric motility and central pain processing, respectively. Behavioral therapies, including cognitive behavioral therapy and hypnotherapy, have shown benefits for refractory FD. Severe and refractory cases may require combination therapies or experimental treatments.

KEY MESSAGES

FD is a disorder of gut-brain interaction involving diverse pathophysiological mechanisms. Individualized treatment based on symptoms and responses to interventions is crucial. Further research is needed to improve the understanding of FD and advance the development of effective therapies.

Overlap of disorders of gut-brain interaction: a systematic review and meta-analysis

BACKGROUND

Rome criteria differentiate distinct types of disorders of gut-brain interaction (DGBI); also known as functional gastrointestinal disorders. Overlap of symptom categories frequently occurs. This systematic review and meta-analysis aimed to define the prevalence of DGBI overlap and compare overlap in population-based, primary care or tertiary care health settings. Furthermore, we aimed to compare symptom severity of psychological comorbidities in DGBI with and without overlap.

METHODS

For this systematic review and meta-analysis we searched MEDLINE (PubMed) and Embase electronic databases from inception until March 1, 2022, for original articles and conference abstracts of observational cross-sectional, case-controlled, or cohort design studies that reported the prevalence of DGBI overlap in adult participants (aged ≥18 years). We included only those studies where the diagnosis of DGBI was based on clinical assessment, questionnaire data, or specific symptom-based criteria. Studies were excluded if reporting on mixed populations of DGBI and organic diseases. Aggregate patient data were extracted from eligible published studies. The prevalence of DGBI overlap in all studies was pooled using the DerSimonian and Laird random effects model, and further analysis stratified by subgroups (care setting, diagnostic criteria, geographic region, and gross domestic product per capita). We also assessed the relationship between DGBI overlap with anxiety, depression, and quality of life symptom scores. This study was registered with PROSPERO (CRD42022311101).

FINDINGS

46 of 1268 screened studies, reporting on 75 682 adult DGBI participants, were eligible for inclusion in this systematic review and meta-analysis. Overall, 24 424 (pooled prevalence 36·5% [95% CI 30·7 to 42·6]) participants had a DGBI overlap, with considerable between-study heterogeneity (I2=99·51, p=0·0001). In the tertiary health-care setting, overlap among participants with DGBI was more prevalent (8373 of 22 617, pooled prevalence 47·3% [95% CI 33·2 to 61·7]) compared with population-based cohorts (11 332 of 39 749, pooled prevalence 26·5% [95% CI 20·5 to 33·4]; odds ratio 2·50 [95% CI 1·28 to 4·87]; p=0·0084). Quality of life physical component scores were significantly lower in participants with DGBI overlap compared with participants without overlap (standardised mean difference -0·47 [95% CI -0·80 to -0·14]; p=0·025). Participants with DGBI overlap had both increased symptom scores for anxiety (0·39 [95% CI 0·24 to 0·54]; p=0·0001) and depression (0·41 [0·30 to 0·51]; p=0·0001).

INTERPRETATION

Overlap of DGBI subtypes is frequent, and is more prevalent in tertiary care settings and associated with more severe symptom manifestations or psychological comorbidities. Despite the large sample size, the comparative analyses revealed substantial heterogeneity, and the results should be interpreted with caution.

FUNDING

National Health and Medical Research Council and Centre for Research Excellence.

Could an Increased Percentage of Immature Granulocytes Accompanying Dyspepsia Predict COVID-19?

Background and Aim: Although vaccination practices continue at a fast pace around the world, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) still threatens people’s lives. In this study, we aimed to determine the presence of SARS-CoV-2 in patients who do not have the typical symptoms of the novel coronavirus disease 2019 (COVID-19), but only present with dyspepsia, and to investigate the role of immature granulocytes in the early diagnosis of these patients. Material and Methods: Adult and pediatric patients suffering from dyspepsia were included in the study. The patients were divided into two groups, ‘‘positive’’ and ‘‘negative’’, based on their SARS-CoV-2 polymerase chain reaction test results. Immature granulocyte count (IG), immature granulocyte percentage (IG%), C-reactive protein (CRP), and neutrophil-to-lymphocyte ratio (NLR) values were recorded. Results: A total of 238 patients, including 25 (10.5%) pediatric and 213 (89.5%) adult patients, were included in the study. A total of 2 (8%) pediatric patients and 17 (7.9%) adult patients tested positive for SARS-CoV-2. The IG, IG%, and CRP parameters were significantly higher in the SARS-CoV-2-positive patients compared to the SARS-CoV-2-negative patients. The optimal cut-off value predictive of COVID-19 infection was determined to be ≥0.650 (sensitivity: 52.6% and specificity: 95.5%, p = 0.001) for IG%. Conclusions: It should be noted that dyspepsia may also be a COVID-19 symptom. IG% values, which can be determined with a hemogram test, a cheap and easily accessible test, may be a warning in the early detection of patients who do not have the typical symptoms of COVID-19.

[Impact of the COVID pandemic on the anxiety of patients with functional gastrointestinal symptoms]

Functional gastrointestinal disorders such as functional dyspepsia (FD) and irritable bowel syndrome (IBS) are stress-associated. The COVID-19 pandemic, which has been rampant since 2020, has caused anxiety and stress in the population. Distancing measures to combat the pandemic have affected mental health. Our objective was to examine the impact of the 3rd lockdown in Germany in December 2020 and January 2021 on the apprehension of patients with FD and IBS.Patients diagnosed with FD or IBS treated in a tertiary or primary care hospital in the South of Baden-Württemberg in 2020 voluntarily participated in an anonymous online survey. Questions about concomitant diseases, concern about COVID-19 and stress perception were answered.A total of 106 patients (♀=67, ♂=38, 1 diverse) participated in the survey. Of these, 16 had FD (♀=9, ♂=6, diverse=1), 80 had IBS (♀=52, ♂=28), and 10 had both (♀=6, ♂=4). The average age was 43.6 years. Depressive and anxiety disorders were most frequently reported comorbidities in both the FD (25% each) and IBS group (20% each), followed by joint wear and tear (FD: 13%, RDS: 14%). In a direct comparison of participants with FD and IBS, those with IBS showed significantly higher scores for an increase in gastrointestinal (GI) symptoms during the pandemic (p=0.007), more frequent presentation to a physician during the pandemic, and greater social withdrawal due to GI symptoms (p=0.05). In direct comparison, those with IBS showed higher scores for fear that vaccination against COVID-19 would adversely affect GI symptoms compared to FD (p=0.05).In times of the pandemic, interdisciplinary collaboration in the care of patients with FD or IBS seems more necessary than ever to address concerns and provide good patient care.

Evidence-based clinical practice guidelines for functional dyspepsia 2021

BACKGROUND

Functional dyspepsia (FD) is a disorder that presents with chronic dyspepsia, which is not only very common but also highly affects quality of life of the patients. In Japan, FD became a disease name for national insurance in 2013, and has been gradually recognized, though still not satisfactory. Following the revision policy of Japanese Society of Gastroenterology (JSGE), the first version of FD guideline was revised this time.

METHOD

Like previously, the guideline was created by the GRADE (grading of recommendations assessment, development and evaluation) system, but this time, the questions were classified to background questions (BQs, 24 already clarified issues), future research questions (FRQs, 9 issues cannot be addressed with insufficient evidence), and 7 clinical questions that are mainly associated with treatment.

RESULTS AND CONCLUSION

These revised guidelines have two major features. The first is the new position of endoscopy in the flow of FD diagnosis. While endoscopy was required to all cases for diagnosis of FD, the revised guidelines specify the necessity of endoscopy only in cases where organic disease is suspected. The second feature is that the drug treatment options have been changed to reflect the latest evidence. The first-line treatment includes gastric acid-secretion inhibitors, acetylcholinesterase (AChE) inhibitors (acotiamide, a prokinetic agent), and Japanese herbal medicine (rikkunshito). The second-line treatment includes anxiolytics /antidepressant, prokinetics other than acotiamide (dopamine receptor antagonists, 5-HT4 receptor agonists), and Japanese herbal medicines other than rikkunshito. The patients not responding to these treatment regimens are regarded as refractory FD.

Impacts of the COVID-19 pandemic on functional dyspepsia and irritable bowel syndrome: A population-based survey

BACKGROUND AND AIM

Functional gastrointestinal disorders are a group of stress-sensitive gut-brain disorders. The COVID-19 outbreak has caused immense stress and anxiety among the general public. Strict measures to counter COVID-19 emergency, including physical distancing, have also taken a toll on physical and mental health. We investigated the impact of the COVID-19 pandemic on the gastrointestinal and psychological symptoms of functional dyspepsia (FD) and irritable bowel syndrome (IBS).

METHODS

An online survey was conducted in Japan for a group of randomly assigned panelists from May 26 to 27, 2020. Each respondent answered a questionnaire on stress, physical distancing, and worries about COVID-19. Gastrointestinal symptoms were assessed to diagnose FD and IBS (Rome III), and psychological symptoms were assessed using the Hospital Anxiety and Depression Scale.

RESULTS

A total of 5157 subjects were finally enrolled, with FD in 8.5%, IBS in 16.6%, and FD-IBS overlap in 4.0%. For both gastrointestinal and psychological symptoms, respondents with FD-IBS overlap showed the worst scores, followed by IBS-alone, then FD-alone respondents. During the COVID-19 pandemic, 11.9% of respondents reported deterioration and 2.8% reported improvement of gastrointestinal symptoms. FD-IBS overlap, psychological disease comorbidity, and stress at work/school were significantly associated with symptom deterioration. Younger age, commuting by public transport, and work/study from home were associated with symptom improvement.

CONCLUSIONS

The COVID-19 pandemic negatively affected FD/IBS subjects, with respondents showing FD-IBS overlap syndrome as the most important independent factor associated with deterioration in gastrointestinal symptoms. Physicians need to take extra care of FD/IBS patients in the post-COVID period.

Impacts of the COVID-19 pandemic on functional dyspepsia and irritable bowel syndrome: A population-based survey

BACKGROUND AND AIM

Functional gastrointestinal disorders are a group of stress-sensitive gut-brain disorders. The COVID-19 outbreak has caused immense stress and anxiety among the general public. Strict measures to counter COVID-19 emergency, including physical distancing, have also taken a toll on physical and mental health. We investigated the impact of the COVID-19 pandemic on the gastrointestinal and psychological symptoms of functional dyspepsia (FD) and irritable bowel syndrome (IBS).

METHODS

An online survey was conducted in Japan for a group of randomly assigned panelists from May 26 to 27, 2020. Each respondent answered a questionnaire on stress, physical distancing, and worries about COVID-19. Gastrointestinal symptoms were assessed to diagnose FD and IBS (Rome III), and psychological symptoms were assessed using the Hospital Anxiety and Depression Scale.

RESULTS

A total of 5157 subjects were finally enrolled, with FD in 8.5%, IBS in 16.6%, and FD-IBS overlap in 4.0%. For both gastrointestinal and psychological symptoms, respondents with FD-IBS overlap showed the worst scores, followed by IBS-alone, then FD-alone respondents. During the COVID-19 pandemic, 11.9% of respondents reported deterioration and 2.8% reported improvement of gastrointestinal symptoms. FD-IBS overlap, psychological disease comorbidity, and stress at work/school were significantly associated with symptom deterioration. Younger age, commuting by public transport, and work/study from home were associated with symptom improvement.

CONCLUSIONS

The COVID-19 pandemic negatively affected FD/IBS subjects, with respondents showing FD-IBS overlap syndrome as the most important independent factor associated with deterioration in gastrointestinal symptoms. Physicians need to take extra care of FD/IBS patients in the post-COVID period.

Eosinophil-associated microinflammation in the gastroduodenal tract contributes to gastric hypersensitivity in a rat model of early-life adversity

Gastric hypersensitivity is a major pathophysiological feature of functional dyspepsia (FD). Recent clinical studies have shown that a large number of patients with FD present with gastroduodenal microinflammation, which may be involved in the pathophysiology of FD. However, no animal model reflecting this clinical characteristic has been established. The underlying mechanism between microinflammation and FD remains unknown. In this study, using a maternal separation (MS)-induced FD model, we aimed to reproduce the gastroduodenal microinflammation and reveal the interaction between gastroduodenal microinflammation and gastric hypersensitivity. The MS model was established by separating newborn Sprague-Dawley rats for 2 h a day from postnatal day 1 to day 10. At 7-8 wk of age, electromyography was used to determine the visceromotor response to gastric distention (GD) and immunohistochemistry was performed to detect distension-associated neuronal activation as well as immunohistological changes. Our results demonstrated that MS-induced FD rats underwent gastric hypersensitivity with GD at 60 and 80 mmHg, which are related to increased p-ERK1/2 expression in the dorsal horn of T9-T10 spinal cords. Eosinophils, but not mast cells, were significantly increased in the gastroduodenal tract, and the coexpression rate of CD11b and major basic protein significantly increased in MS rats. Treatment with dexamethasone reversed gastric hypersensitivity in MS-induced FD rats by inhibiting eosinophil infiltration. These findings indicated that neonatal MS stress induces eosinophil-associated gastroduodenal microinflammation and gastric hypersensitivity in adulthood in rats. Microinflammation contributes to gastric hypersensitivity; therefore, anti-inflammatory therapy may be effective in treating patients with FD with gastroduodenal microinflammation.NEW & NOTEWORTHY We showed for the first time that neonatal MS stress-induced FD rats undergo gastroduodenal eosinophil-associated microinflammation in adulthood. Suppression of microinflammation attenuated gastric hypersensitivity in MS rats. These findings established a functional link between microinflammation and gastric hypersensitivity, which may provide a potential clue for the clinical treatment of FD.

Functional Dyspepsia: A Narrative Review With a Focus on Sex-Gender Differences

Functional dyspepsia (FD) is among the most common gastrointestinal disorders affecting quality of life (QoL). As it frequently occurs in women than in men the comparison of various aspects including prevalence, clinical manifestations, and QoL in FD between women and men is very important for understanding the disease distribution and burden, evaluating treatment options, developing new drugs, and allocating medical resources. However, little is known about sex or gender differences among patients with FD. In spite of limited studies, consistent points are that FD occurs more often in women than in men and there are several symptom differences between men and women with FD. In addition, women with FD tend to have lower QoL than men with FD. Similarly, the pathophysiology of FD likely to vary depending on gender. Furthermore, a sex-gender-oriented approach in healthcare system could enhance understanding heterogeneous patients suffering from FD. Due to the sex-gender differences in physiological and psychological factors, treatment strategies should differ between women and men with FD. In conclusion, an individualized and multicomponent approach that considers sex and gender issues might improve FD treatment and improve patient Qol, especially for women.

Association between child abuse exposure and the risk of psychiatric disorders: A nationwide cohort study in Taiwan

BACKGROUND

Child abuse affects children physiologically and psychologically, increasing the risk of future psychiatric disorders.

OBJECTIVE

To assess whether child abuse victims have a higher incidence of future psychiatric disorders or substance abuse.

PARTICIPANTS AND SETTING

The participants consisted of a nationwide, population-based cohort selected in accordance with the Taiwan National Health Insurance Research Database. All children were enrolled between 2000 and 2015.

METHODS

This was a retrospective study with a matched-cohort design. Children who experienced child abuse were identified using International Classification of Disease codes and compared with children who had not experienced child abuse by measuring rates of anxiety disorders, depressive disorders, bipolar disorders, sleep disorders, posttraumatic stress disorder/acute stress disorder, eating disorders, substance-related disorders (alcohol use disorder and illicit drug use disorder), psychotic disorders, and organic mental disorders.

RESULTS

The psychiatric disorder risk was significantly higher in victims of child abuse than in controls (adjusted hazard ratio, 2.15; 95 % confidence interval, 1.92-2.40; P < 0.001). The Kaplan-Meier analysis revealed a significantly higher 15-year cumulative incidence of psychiatric disorders among child abuse victims than among controls (394.57 vs. 317.56 events per 100,000 person-years; log-rank test, P <  0.001).

CONCLUSIONS

In Taiwan, child abuse is associated with increased psychiatric disorder and substance abuse risk. Individuals involved in caring for abused children, including family members, pediatricians, nurses, and social workers, as well as policy makers, should be aware of this risk. Early referral of child abuse victims to pediatric psychiatrists may help detect high-risk cases and facilitate early intervention.

Duodenal low-grade inflammation and expression of tight junction proteins in functional dyspepsia

BACKGROUND

Duodenal changes in functional dyspepsia (FD) might be related to the development of symptoms. However, relationships among low-grade inflammation, Helicobacter pylori infection, and protein expression by tight junctions (TJs) in the duodenum are unclear. We therefore aimed to determine whether duodenal inflammation and genes associated with TJ proteins are associated with FD.

METHODS

We evaluated inflammatory cell infiltration of the duodenum, H pylori infection, and genes associated with TJ proteins in duodenal biopsy specimens from 35 patients with FD according to the Rome III diagnostic questionnaire and from 31 asymptomatic controls without structural diseases. We immunohistochemically detected eosinophils and mast cells and counted them. The expression of claudins, occludin, and zonula occludens (ZO)-1 mRNA was evaluated using quantitative RT-PCR. Infection with H pylori was determined by measuring serum antibodies, rapid urease or urea breath tests, and endoscopic findings.

RESULTS

Sex, age, and H pyloriinfection rates did not differ between patients with FD and controls. The numbers of eosinophils and mast cells were significantly increased in patients with FD compared with controls and were significantly correlated. Inflammatory cell counts in the duodenum were not associated with H pylori infection status. Claudin-3 mRNA expression was increased in the patients with FD.

CONCLUSIONS

Subtle inflammation identified in the duodenum of patients with FD might be associated with the onset and persistence of dyspeptic symptoms.

Effect of probiotic Bifidobacterium bifidum G9-1 on the relationship between gut microbiota profile and stress sensitivity in maternally separated rats

Although gut microbiota and early life events are likely involved in the development of irritable bowel syndrome (IBS), it remains unclear how these factors interact in the pathophysiology of IBS. In the present study, using rats subjected to maternal separation (MS) as a model of IBS, we investigated interrelationships among gut microbiota, stress susceptibility and intestinal permeability, and examined the effect of the probiotic Bifidobacterium bifidum G9-1 (BBG9-1) on those interrelationships. When compared with the controls at postnatal day 20, MS rats showed hypercorticosteronemia, enhanced intestinal permeability and changes in gut microbiota structure. All of these changes in MS rats were prevented by treatment with BBG9-1. Although the gut microbiota profile and basal serum corticosterone level did not differ between MS and control rats at postnatal day 56, MS rats showed hypersensitivity to restraint stress in terms of serum corticosterone level and fecal frequency. However, such hypersensitivity was not observed in MS rats treated with BBG9-1. These findings suggest that MS initiates the link between gut microbiota alteration and hypersensitivity to stress and that the triggering of this process can be prevented by the treatment with the probiotic BBG9-1.

Functional dyspepsia

Functional dyspepsia is one of the most prevalent functional gastrointestinal disorders. Functional dyspepsia comprises three subtypes with presumed different pathophysiology and aetiology: postprandial distress syndrome (PDS), epigastric pain syndrome (EPS) and a subtype with overlapping PDS and EPS features. Functional dyspepsia symptoms can be caused by disturbed gastric motility (for example, inadequate fundic accommodation or delayed gastric emptying), gastric sensation (for example, sensations associated with hypersensitivity to gas and bloating) or gastric and duodenal inflammation. A genetic predisposition is probable but less evident than in other functional gastrointestinal disorders, such as irritable bowel syndrome (IBS). Psychiatric comorbidity and psychopathological state and trait characteristics could also play a part, although they are not specific to functional dyspepsia and are less pronounced than in IBS. Possible differential diagnoses include Helicobacter pylori infection and peptic ulceration. Pharmacological therapy is mostly based on the subtype of functional dyspepsia, such as prokinetic and fundus-relaxing drugs for PDS and acid-suppressive drugs for EPS, whereas centrally active neuromodulators and herbal drugs play a minor part. Psychotherapy is effective only in a small subset of patients, whereas quality of life can be severely affected in nearly all patients. Future therapies might include novel compounds that attempt to treat the underlying gastric and duodenal inflammation.

Women and functional dyspepsia

Functional dyspepsia is relatively common yet poorly understood. The best accepted diagnostic criteria are the Rome III criteria. The epidemiology, healthcare seeking rates, impact and pathophysiology are reviewed with a focus on women. Treatment is limited with no clearly established regimen currently recommended. Duodenal eosinophilia may be found in a subset. Proton pump inhibitors and prokinetic agents represent the standard therapeutic regimen after Helicobacter pylori infection has been eliminated. Some novel agents such as the prokinetic acotiamide appear promising; however, the need for a safe and efficacious treatment remains largely unmet. This review also describes the currently available management options for functional dyspepsia.

Small Intestinal Bacterial Overgrowth in Patients with Refractory Functional Gastrointestinal Disorders

Background/Aims

Small intestinal bacterial overgrowth (SIBO) is considered to be involved in the pathogenesis of functional gastrointestinal disorders (FGID). However, the prevalence and clinical conditions of SIBO in patients with FGID remain to be fully elucidated. Here, we examined the frequency of SIBO in patients with refractory FGID.

Methods

We prospectively enrolled patients with refractory FGID based on Rome III criteria. A glucose hydrogen breath test (GHBT) was performed using a gas analyzer after an overnight fast, with breath hydrogen concentration measured at baseline and every 15 minutes after administration of glucose for a total of 3 hours. A peak hydrogen value ≥ 10 ppm above the basal value between 60 and 120 minutes after administration of glucose was diagnosed as SIBO.

Results

A total of 38 FGID patients, including 11 with functional dyspepsia (FD), 10 with irritable bowel syndrome (IBS), and 17 with overlapping with FD and IBS, were enrolled. Of those, 2 (5.3%) were diagnosed with SIBO (one patient diagnosed with FD; the other with overlapping FD and IBS). Their symptoms were clearly improved and breath hydrogen levels decreased to normal following levofloxacin administration for 7 days.

Conclusions

Two patients initially diagnosed with FD and IBS were also diagnosed with SIBO as assessed by GHBT. Although the frequency of SIBO is low among patients with FGID, it may be important to be aware of SIBO as differential diagnosis when examining patients with refractory gastrointestinal symptoms, especially bloating, as a part of routine clinical care.

Epidemiology of Functional Gastrointestinal Disorders in Japan and in the World

Functional gastrointestinal disorders (FGIDs), represented by functional dyspepsia (FD) and irritable bowel syndrome (IBS), are a group of disorders that include variable combinations of chronic or recurrent gastrointestinal symptoms not explained by structural or biochemical abnormalities. FGIDs account for a significant percentage of patients seen in primary care settings with abdominal symptoms. Although the definition of FGIDs can easily affect the prevalence, the prevalences of dyspepsia/FD and IBS diagnosed by the Rome III criteria in the general population are 5.3–20.4% and 1.1–29.2%, respectively. Recent reports of FD and IBS defined by the Rome III criteria indicated a female predominance. Regarding the subtype prevalence of FD, postprandial distress syndrome was more prevalent than epigastric pain syndrome (5.6–13.9% vs 0.9–9.5%). The subtype prevalence of IBS is characterized by male predominance for IBS with diarrhea and female predominance for IBS with constipation. Factors affecting the development of FGIDs such as epidemiological factors including genetic and environmental factors, are important. Gene polymorphisms are involved in the development of FGIDs. The prevalence differs among races and geographic areas. Foods may affect the development of FGIDs, but the causal relationships between food and FGIDs are not conclusive. The symptoms often regress and appear in the course of these entities. Building a favorable patient-doctor relationship is effective for controlling symptoms of FGIDs. Physicians should explain that FGIDs are highly prevalent conditions, impair the patients’ quality of life even without evident underlying organic causes and are not life-threatening conditions to ensure patients’ understanding.