Piloting an intraoral pH device to track gastroesophageal reflux in adults.

This study evaluated in vivo, an intraoral device against the gold standard esophageal device for gastroesophageal reflux disease (GERD) monitoring. Subjects scheduled for a catheter-based esophageal pH/impedance testing at a gastroenterology clinic were recruited. They were screened using the GerdQ questionnaire, demographics and dental conditions recorded. A prototype intraoral device, consisting of a Bravo™ capsule embedded in an Essix-style retainer fabricated for each subject, monitored intraoral pH. Concurrently, subjects underwent 24-h esophageal pH-impedance monitoring. A self-administered survey elicited the comfort and acceptance of both devices. The study recruited ten adult subjects (23 to 60-years-old) with a median GerdQ score of 9.5 corresponding to a 79% likelihood of GERD. Subjects with severe dental erosion had significantly (p < 0.05) higher acid exposure time and more non-meal reflux events. No adverse events were associated with the intraoral device while one was recorded for the esophageal device. The intraoral device was significantly more comfortable to place, more comfortable to wear, and interfered less with daily routine compared to the esophageal device. Accuracy of the intraoral device ranged between 86.15% and 37.82%. Being more tolerable than traditional esophageal pH monitoring, intraoral pH monitoring may be a useful adjunct for the diagnosis and management of GERD.

What Has Longitudinal 'Omics' Studies Taught Us about Irritable Bowel Syndrome? A Systematic Review.

Irritable bowel syndrome is a prototypical disorder of the brain-gut-microbiome axis, although the underlying pathogenesis and mechanisms remain incompletely understood. With the recent advances in 'omics' technologies, studies have attempted to uncover IBS-specific variations in the host-microbiome profile and function. However, no biomarker has been identified to date. Given the high inter-individual and day-to-day variability of the gut microbiota, and a lack of agreement across the large number of microbiome studies, this review focused on omics studies that had sampling at more than one time point. A systematic literature search was performed using various combinations of the search terms "Irritable Bowel Syndrome" and "Omics" in the Medline, EMBASE, and Cochrane Library up to 1 December 2022. A total of 16 original studies were reviewed. These multi-omics studies have implicated Bacteroides, Faecalibacterium prausnitzii, Ruminococcus spp., and Bifidobacteria in IBS and treatment response, found altered metabolite profiles in serum, faecal, or urinary samples taken from IBS patients compared to the healthy controls, and revealed enrichment in the immune and inflammation-related pathways. They also demonstrated the possible therapeutic mechanisms of diet interventions, for example, synbiotics and low fermentable oligosaccharides, disaccharides, monosaccharides, and polyol (FODMAP) diets on microbial metabolites. However, there was significant heterogeneity among the studies and no uniform characteristics of IBS-related gut microbiota. There is a need to further study these putative mechanisms and also ensure that they can be translated to therapeutic benefits for patients with IBS.

Volatile organic compounds as potential biomarkers of irritable bowel syndrome: A systematic review.

BACKGROUND: Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disease characterized by intermittent abdominal pain with altered bowel habits. Due to the condition's chronicity, patients suffer from poor quality of life, while the healthcare burden continues to grow. There is currently no reliable biomarker for the diagnosis of IBS, and the current approach depends on ruling-out organic diseases such as inflammatory bowel disease (IBD) and colorectal cancer by markers of inflammation like fecal calprotectin and C-reactive protein, or invasive procedures like a colonoscopy. Volatile organic compounds (VOCs) are growing in popularity as a biomarker due to its accuracy and ease of use. PURPOSE: This systematic review of Medline and Cochrane's databases aimed to identify VOCs in the diagnosis of IBS. 57% of the studies proved that VOCs could identify IBS patients from healthy controls with AUC ranging from 0.83 to 0.99. Studies that distinguished IBS from IBD patients had slightly higher AUC of 0.87-0.98. Combining VOC into panels allowed the creation of discriminative algorithms. Though current research is limited by areas of heterogeneity in VOC sampling and small sample sizes, our review shows that VOC analysis has the potential to be a noninvasive point-of-care test that differentiates IBS from other organic gastrointestinal diseases.

Asia-Pacific guidelines for managing functional dyspepsia overlapping with other gastrointestinal symptoms.

Contemporary systems for the diagnosis and management gastrointestinal symptoms not attributable to organic diseases (Functional GI Disorders, FGID, now renamed Disorders of Gut-Brain Interaction, DGBI) seek to categorize patients into narrowly defined symptom-based sub-classes to enable targeted treatment of patient cohorts with similar underlying putative pathophysiology. However, an overlap of symptom categories frequently occurs and has a negative impact on treatment outcomes. There is a lack of guidance on their management. An Asian Pacific Association of Gastroenterology (APAGE) working group was set up to develop clinical practice guidelines for management of patients with functional dyspepsia (FD) who have an overlap with another functional gastrointestinal disorder: FD with gastroesophageal reflux (FD-GERD), epigastric pain syndrome with irritable bowel syndrome (EPS-IBS), postprandial distress syndrome with IBS (PDS-IBS), and FD-Constipation. We identified putative pathophysiology to provide a basis for treatment recommendations. A management algorithm is presented to guide primary and secondary care clinicians.

Is There an Increasing Incidence of Gastroesophageal Junctional Adenocarcinoma and Barrett Esophagus in Asia? A Review of Diagnostic Conundrums.

BACKGROUND: Epidemiology data of gastroesophageal junction (GEJ) cancers in Asia are extremely scarce. It is hardly registered by any cancer registry in the region, and only a few reports are available. Based on existing literature works, the overall trend indicates similar or gradually increasing GEJ cancers in Asia but comparably less than the West. The increasing trend in Asia is likely a result of rising risk factors, especially of gastroesophageal reflux disease and obesity. SUMMARY: However, epidemiology data may be misleading due to several contentious diagnostic issues. The diagnostic conundrums are due to inherent complexity of the GEJ as a functional and pathological unit. Challenging diagnostic issues in Asia include the following: nonstandardized landmark of the GEJ, misclassification of Barrett esophagus, targeted versus nontargeted tissue sampling, histopathology disagreement and challenges in screening or surveillance of dysplastic BE and early GEJ cancer. The recent Asian-Pacific survey led by the Asian Barrett Consortium (ABC) has provided useful insights into these contentious issues. A key learning point from these diagnostic limitations is that the awareness of the disease and adherence to existing recommendations or guidelines are poor in the region. Key Messages: Standardization in diagnostic methodology is vital for accurate epidemiology data, and this can only come from better awareness and adherence through educational and international efforts. Last, surveillance strategy may need a paradigm shift from a purely diagnostic approach to a combined targeted surveillance and treatment approach using novel endoscopic techniques.

Gastro-esophageal reflux disease (GERD) after peroral endoscopic myotomy (POEM).

BACKGROUND: Peroral endoscopic myotomy (POEM) is gaining traction as a minimally invasive treatment of achalasia. Increased reflux is reported after POEM but the incidence, type and severity of reflux are not fully understood. We aimed to study the prevalence and nature of reflux after POEM and correlate reflux with endoscopy and pH-impedance findings. METHODS: This is a prospective cohort study of achalasia patients undergoing POEM since 2014. Data from Eckardt and GERD symptom scores, high-resolution oesophageal manometry (HRM) and gastroscopy were performed pre-procedure and repeated at 1-year follow-up. Data from 24-h pH-impedance, if performed, were also recorded. A standardized questionnaire was used to determine the severity and frequency of heartburn symptoms and the composite score for each patient was calculated. RESULTS: 58 patients underwent POEM between January 2014 and October 2018. The efficacy of POEM at 1 year was 93.0%. We observed reduction of median Integrated Relaxation Pressure (IRP) from 23.5 ± 33.1 mmHg to 13.4 ± 7.71 mmHg (p = 0.005) and mean Eckardt score improved from 6.09 ± 2.43 points to 1.16 ± 1.70 points (p < 0.001). At 1 year, 43.1% (n = 25) had symptomatic reflux. Of the 40 patients who underwent repeated gastroscopy, 60.0% (n = 24) had endoscopic evidence of oesophagitis with seven patients (18%) diagnosed with Grade C or D oesophagitis. 43.1% (n = 25) of patients had pH-impedance done post-POEM off PPIs. 14 patients (56%) had increased acid exposure. Sixteen percent of reflux episodes were acidic and 77.3% were weakly acidic. CONCLUSION: POEM was an effective treatment for achalasia. However, GERD was common after POEM with incidence of 43% on symptom score, 60% on endoscopy and 56% on pH-impedance test. Post-POEM reflux appeared to be predominantly acidic in nature. Routine surveillance for GERD after POEM is recommended.

Guidance on performance and reporting of high-resolution oesophageal manometry and ambulatory pH monitoring in Singapore.

INTRODUCTION: We aimed to provide a practical and evidence-based guide on the indications, performance and reporting of high-resolution oesophageal manometry (HRM) and ambulatory pH monitoring (PHM) in adult patients in Singapore. METHODS: The guideline committee comprised local gastroenterologists from public and private sectors with particular expertise in aspects of HRM and PHM, and it was tasked to produce evidence-based statements on the indications, performance and reporting of these tests. Each committee member performed literature searches to retrieve relevant articles within the context of domains to which they were assigned. RESULTS: Twelve recommendation statements were created and summarised. CONCLUSION: Standardising key aspects of HRM and PHM is imperative to ensure the delivery of high-quality care. We reported the development of recommendations for the performance and interpretation of HRM and ambulatory reflux monitoring in Singapore.

Review of the role of gastrointestinal multiplex polymerase chain reaction in the management of diarrheal illness.

Acute and chronic diarrheal illness secondary to gastrointestinal infection is a significant cause of morbidity and mortality around the world. A cornerstone of management includes prompt diagnosis and appropriate treatment of culprit pathogens. Timely diagnosis can improve patient care, assist in infection control, and prevent disease outbreaks. Historical methods of diagnosis include traditional culture methods and stool analysis. These are limited by long turnaround time and inability to simultaneously assess multiple pathogens. The advent of multiplexed nucleic acid amplification tests first began with the Food and Drug Administration-approved respiratory virus multiplex polymerase chain reaction (PCR) panel in 2009, followed by gastrointestinal infections in 2013, and neurological infections in 2014. We conducted a review of current literature pertaining to the clinical utility of a gastrointestinal multiplex PCR in management of acute and chronic diarrhea in patients. To date, seven platforms approved by the US Food and Drug Administration are used in detection of various bacterial, viral, and parasitic causative organisms for diagnosis of gastrointestinal infections. The sensitivity and specificity of each assay vary depending on the tested organism. Interpretation of a positive result has to be tailored to the clinical context. Further studies are required to establish the utility of gastrointestinal multiplex PCR from a cost-based perspective, whether specific enteropathogens such as Clostridioides difficile are better assessed with toxin gene detection and whether new parameters such as cycle threshold values can improve clinical application of test results.

Multinational survey on the preferred approach to management of Barrett's esophagus in the Asia-Pacific region.

BACKGROUND: Major societies provide differing guidance on management of Barrett's esophagus (BE), making standardization challenging. AIM: To evaluate the preferred diagnosis and management practices of BE among Asian endoscopists. METHODS: Endoscopists from across Asia were invited to participate in an online questionnaire comprising eleven questions regarding diagnosis, surveillance and management of BE. RESULTS: Five hundred sixty-nine of 1016 (56.0%) respondents completed the survey, with most respondents from Japan (n = 310, 54.5%) and China (n = 129, 22.7%). Overall, the preferred endoscopic landmark of the esophagogastric junction was squamo-columnar junction (42.0%). Distal palisade vessels was preferred in Japan (59.0% vs 10.0%, P < 0.001) while outside Japan, squamo-columnar junction was preferred (59.5% vs 27.4%, P < 0.001). Only 16.3% of respondents used Prague C and M criteria all the time. It was never used by 46.1% of Japanese, whereas 84.2% outside Japan, endoscopists used it to varying extents (P < 0.001). Most Asian endoscopists (70.8%) would survey long-segment BE without dysplasia every two years. Adherence to Seattle protocol was poor with only 6.3% always performing it. 73.2% of Japanese never did it, compared to 19.3% outside Japan (P < 0.001). The most preferred (74.0%) treatment of non-dysplastic BE was proton pump inhibitor only when the patient was symptomatic or had esophagitis. For BE with low-grade dysplasia, 6-monthly surveillance was preferred in 61.9% within Japan vs 47.9% outside Japan (P < 0.001). CONCLUSION: Diagnosis and management of BE varied within Asia, with stark contrast between Japan and outside Japan. Most Asian endoscopists chose squamo-columnar junction to be the landmark for esophagogastric junction, which is incorrect. Most also did not consistently use Prague criteria, and Seattle protocol. Lack of standardization, education and research are possible reasons.

Poor Outcomes of Cirrhosis due to Nonalcoholic Steatohepatitis Compared With Hepatitis B After Decompensation With Ascites.

INTRODUCTION: Decompensation with ascites portends a poor prognosis in cirrhosis. The aim of this study was to compare the outcomes of patients with nonalcoholic steatohepatitis (NASH) with hepatitis B virus (HBV) cirrhosis after decompensation with ascites. METHODS: We conducted a retrospective study to evaluate the outcomes of patients with NASH and HBV cirrhosis who were admitted to hospital for first-onset ascites from January 1, 2004, to June 30, 2015. They were followed up until death, liver transplantation, or loss to follow up. RESULTS: Patients with NASH had lower median (interquartile range) Model for End-Stage Liver Disease score (11 [9-14] vs 14 [11-17], P < 0.001). Over 60 months, patients with NASH cirrhosis had higher cumulative incidence of dilutional hyponatremia (P < 0.001) and refractory ascites (P = 0.028). They also had higher cumulative incidence of cirrhosis-related deaths and liver transplantation compared with HBV cirrhosis (65.7%; [95% confidence interval (CI) 53.6-75.4] vs 42.5% [95% CI 32.4-55.2], P = 0.008). Multivariable competing risk analysis showed that NASH (subdistribution hazard ratio [sHR] 1.88 [95% CI 1.14-3.11], P = 0.014), non-Chinese ethnicity (sHR 1.63 [95% CI 1.06-2.50], P = 0.027), history of hepatocellular carcinoma (sHR 1.76 [95% CI 1.05-2.95], P = 0.033), estimated glomerular filtration rate <60 mL/min/1.73 m2 (sHR 1.70 [95% CI 1.09-2.65], P = 0.020), and Model for End-Stage Liver Disease score ≥15 (sHR 3.26 [95% CI 2.11-5.05], P < 0.001) were independent predictors of poor transplant-free survival. DISCUSSION: Patients with decompensated cirrhosis due to NASH had much poorer prognosis compared with HBV with more complications and greater healthcare resource utilization. Greater awareness is necessary for early diagnosis of NASH before decompensation.

The causal effects of chronic air pollution on the intensity of COVID-19 disease: Some answers are blowing in the wind

The threats posed by COVID-19 have catalyzed a search by researchers across multiple disciplines for policy-relevant findings about critical risk factors. We contribute to this effort by providing causal estimates of the link between increased chronic ambient pollutant concentrations and the intensity of COVID-19 disease, as measured by deaths and hospitalizations in New York City from March through August, 2020. Given concerns about unobservable characteristics that contribute to both ambient air pollutant concentrations and the impacts of COVID-19 disease, we instrument for pollutant concentrations using the time spent downwind of nearby highways and estimate key causal relationships using two-stage least squares models. The causal links between increases in concentrations of our traffic-related air pollutants (PM2.5, NO2, and NO) and COVID-19 deaths are much larger than the correlations presented in recent observational studies. We find that a 0.16 g/m3 increase in average ambient PM2.5 concentration leads to an approximate 30% increase in COVID-19 deaths. This is the change in concentration associated with being downwind of a nearby highway. We see that this effect is mostly driven by residents with at least 75 years of age. In addition to emphasizing the importance of searching for causal relationships, our analysis highlights the value of increasing the density of pollution-monitoring networks and suggests potential benefits of further tightening of Clean Air Act amendments, as our estimated effects occur at concentrations well below thresholds set by the National Ambient Air Quality Standards.

Guidance on performance and reporting of high-resolution oesophageal manometry and ambulatory pH monitoring in Singapore

INTRODUCTION@#We aimed to provide a practical and evidence-based guide on the indications, performance and reporting of high-resolution oesophageal manometry (HRM) and ambulatory pH monitoring (PHM) in adult patients in Singapore.@*METHODS@#The guideline committee comprised local gastroenterologists from public and private sectors with particular expertise in aspects of HRM and PHM, and it was tasked to produce evidence-based statements on the indications, performance and reporting of these tests. Each committee member performed literature searches to retrieve relevant articles within the context of domains to which they were assigned.@*RESULTS@#Twelve recommendation statements were created and summarised.@*CONCLUSION@#Standardising key aspects of HRM and PHM is imperative to ensure the delivery of high-quality care. We reported the development of recommendations for the performance and interpretation of HRM and ambulatory reflux monitoring in Singapore.

Cytotoxic lymphocytes are dysregulated in multisystem inflammatory syndrome in children

Multisystem inflammatory syndrome in children (MIS-C) presents with fever, inflammation and multiple organ involvement in individuals under 21 years following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. To identify genes, pathways and cell types driving MIS-C, we sequenced the blood transcriptomes of MIS-C cases, pediatric cases of coronavirus disease 2019, and healthy controls. We define a MIS-C transcriptional signature partially shared with the transcriptional response to SARS-CoV-2 infection and with the signature of Kawasaki disease, a clinically similar condition. By projecting the MIS-C signature onto a co-expression network, we identified disease gene modules and found genes downregulated in MIS-C clustered in a module enriched for the transcriptional signatures of exhausted CD8+ T-cells and CD56dimCD57+ NK cells. Bayesian network analyses revealed nine key regulators of this module, including TBX21, a central coordinator of exhausted CD8+ T-cell differentiation. Together, these findings suggest dysregulated cytotoxic lymphocyte response to SARS-Cov-2 infection in MIS-C.

Escitalopram-induced liver injury: A case report and review of literature.

BACKGROUND: Depression is a growing public health problem that affects over 350 million people globally and accounts for approximately 7.5% of healthy years lost due to disability. Escitalopram, one of the first-line medications for the treatment of depression, is a selective serotonin reuptake inhibitor and one of the most commonly prescribed antidepressant medications worldwide. Although thought to be generally safe and with minimal drug-drug interactions, we herein present an unusual case of cholestatic liver injury, likely secondary to escitalopram initiation. CASE SUMMARY: A 56-year-old Chinese lady presented with fever and cholestatic liver injury two weeks after initiation of escitalopram for the treatment of psychotic depression. Physical examination was unremarkable. Further investigations, including a computed tomography scan of the abdomen and pelvis and tests for hepatitis A, B and C and for autoimmune liver disease were unyielding. Hence, a diagnosis of escitalopram-induced liver injury was made. Upon stopping escitalopram, repeat liver function tests showed downtrending liver enzymes with eventual normalization of serum aspartate aminotransferase and alanine aminotransferase one-week post-discharge. CONCLUSION: Clinicians should be aware of the possibility of escitalopram-induced liver injury when initiating depressed patients on antidepressant treatment. This requires extra vigilance as most patients may remain asymptomatic. Measurement of liver function tests could be considered after initiation of antidepressant treatment, especially in patients with pre-existing liver disease.

Is there an association between Helicobacter pylori infection and irritable bowel syndrome? A meta-analysis.

BACKGROUND: Irritable bowel syndrome (IBS) is a prevalent and debilitating gastrointestinal condition. Research has reported persistent, low-grade mucosal inflammation and significant overlaps between patients with IBS and those with dyspepsia, suggesting a possible pathogenic role of Helicobacter pylori (H. pylori) in IBS. This study therefore aimed to provide the first systematic review and meta-analysis on the association between H. pylori infection and IBS. AIM: To investigate the association between H. pylori infection and IBS. METHODS: Using the keywords "H. pylori OR Helicobacter OR Helicobacter pylori OR infection" AND "irritable bowel syndrome OR IBS", a preliminary search of PubMed, Medline, Embase, Cochrane Database of Systematic Reviews, Web of Science, Google Scholar and WanFang databases yielded 2924 papers published in English between 1 January 1960 and 1 June 2018. Attempts were also made to search grey literature. RESULTS: A total of 13 clinical studies were systematically reviewed and nine studies were included in the final meta-analysis. Random-effects meta-analysis found a slight increased likelihood of H. pylori infection in patients with IBS, albeit this was not statistically significant (pooled odds ratio 1.47, 95% confidence interval: 0.90-2.40, P = 0.123). It must also be acknowledged that all of the available studies reported only crude odd ratios. H. pylori eradication therapy also does not appear to improve IBS symptoms. Although publication bias was not observed in the funnel plot, there was a high degree of heterogeneity amongst the studies included in the meta-analysis (I 2 = 87.38%). CONCLUSION: Overall, current evidence does not support an association between IBS and H. pylori infection. Further rigorous and detailed studies with larger sample sizes and after H. pylori eradication therapy are warranted.

A Systematic Review of the Role of Prebiotics and Probiotics in Autism Spectrum Disorders.

Background: Autism spectrum disorder (ASD) is a complex developmental condition typically characterized by deficits in social and communicative behaviors as well as repetitive patterns of behaviors. Despite its prevalence (affecting 0.1% to 1.8% of the global population), the pathogenesis of ASD remains incompletely understood. Patients with ASD are reported to have more frequent gastrointestinal (GI) complaints. There is some anecdotal evidence that probiotics are able to alleviate GI symptoms as well as improve behavioral issues in children with ASD. However, systematic reviews of the effect of prebiotics/probiotics on ASD and its associated symptoms are lacking. Methods: Using the keywords (prebiotics OR probiotics OR microbiota OR gut) AND (autism OR social OR ASD), a systematic literature search was conducted on PubMed, EMBASE, Medline, Clinicaltrials.gov and Google Scholar databases. The inclusion criteria were original clinical trials, published in English between the period 1st January 1988 and 1st February 2019. Results: A total of eight clinical trials were systematically reviewed. Two clinical trials examined the use of prebiotic and/or diet exclusion while six involved the use of probiotic supplementation in children with ASD. Most of these were prospective, open-label studies. Prebiotics only improved certain GI symptoms; however, when combined with an exclusion diet (gluten and casein free) showed a significant reduction in anti-sociability scores. As for probiotics, there is limited evidence to support the role of probiotics in alleviating the GI or behavioral symptoms in children with ASD. The two available double-blind, randomized, placebo-controlled trials found no significant difference in GI symptoms and behavior. Conclusion: Despite promising preclinical findings, prebiotics and probiotics have demonstrated an overall limited efficacy in the management of GI or behavioral symptoms in children with ASD. In addition, there was no standardized probiotics regimen, with multiple different strains and concentrations of probiotics, and variable duration of treatments.

A Systematic Review of the Effect of Probiotic Supplementation on Schizophrenia Symptoms.

BACKGROUND: Derangements of the gut microbiome have been linked to increased systemic inflammation and central nervous system disorders, including schizophrenia. This systematic review thus aimed to investigate the hypothesis that probiotic supplementation improves schizophrenia symptoms. METHODS: By using the keywords (probiotic OR gut OR microbiota OR microbiome OR yogurt OR yoghurt OR lactobacillus OR bifidobacterium) AND (schizophrenia OR psychosis), a preliminary search of the PubMed, Medline, Embase, Google Scholar, ClinicalTrials.gov, Clinical Trials Register of the Cochrane Collaboration Depression, Anxiety and Neurosis Group (CCDANTR), and Cochrane Field for Complementary Medicine databases yielded 329 papers published in English between January 1, 1960 and May 1, 2018. Attempts were made to search grey literature as well. RESULTS: Three clinical studies were reviewed, comparing the use of probiotics to placebo controls. Applying per-protocol analysis and a fixed-effects model, there was no significant difference in schizophrenia symptoms between the group that received probiotic supplementation and the placebo group post-intervention as the standardized mean difference was -0.0884 (95% CI -0.380 to 0.204, p = 0.551). Separate analyses were performed to investigate the effect of probiotic supplementation on positive or negative symptoms of schizophrenia alone. In both instances, no significant difference was observed as well. CONCLUSION: Based on current evidence, limited inferences can be made regarding the efficacy of probiotics in schizophrenia. Although probiotics may have other benefits, for example to regulate bowel movement and ameliorate the metabolic effects of antipsychotic medications, the clinical utility of probiotics in the treatment of schizophrenia patients remains to be validated by future clinical studies.

Systematic review with meta-analysis: The association between post-traumatic stress disorder and irritable bowel syndrome.

BACKGROUND AND AIM: Post-traumatic stress disorder (PTSD) is a psychiatric condition characterized by symptoms of hyperarousal and hypervigilance. Increasing research on the "gut-brain" axis (bidirectional signaling between the gut and the brain) has drawn links between PTSD and irritable bowel syndrome (IBS), an exceedingly common yet incompletely understood gastrointestinal condition. This meta-analysis thus aimed to examine the body of evidence and extent of association of PTSD with IBS. METHODS: Using the keywords [early abuse OR childhood abuse OR violence OR trauma OR PTSD] AND [irritable bowel syndrome or IBS], a preliminary search on the PubMed, Medline, Embase, ScienceDirect, PsychINFO, Web of Science, and Google Scholar databases yielded 11,257 papers published in English between January 1, 1988, and May 1, 2018. Of these, only eight studies were included in the final meta-analysis. RESULTS: The eight studies (four cross-sectional and four cohort) contained a total of 648,375 subjects. Most studies were from the USA and conducted on army veterans. The funnel plot revealed a roughly symmetrical distribution of studies, and Egger test was not significant for publication bias (P = 0.583). Random-effects meta-analysis found PTSD to be a significant risk factor for IBS (pooled odds ratio 2.80, 95% confidence interval: 2.06 to 3.54, P < 0.001). CONCLUSIONS: Overall, PTSD is associated with an increased likelihood of IBS. This is the first meta-analysis to specifically examine the association between PTSD and IBS, and it provides insights into the probable (patho)physiology and management of IBS, supporting a holistic consideration of the psychosocial aspects of IBS and further research into effective multi-modal therapeutics.