Waist belt and central obesity cause partial hiatus hernia and short-segment acid reflux in asymptomatic volunteers

Proximal Gastric Pressurization After Sleeve Gastrectomy Associates With Gastroesophageal Reflux

INTRODUCTION

Sleeve gastrectomy (SG) results in persistent or de novo reflux more often than Roux-en-Y gastric bypass (RYGB). We investigated pressurization patterns in the proximal stomach on high-resolution manometry (HRM) to determine associations with reflux after SG.

METHODS

Patients undergoing HRM and ambulatory pH-impedance monitoring after SG and RYGB over a 2-year period (2019-2020) were included. For each included patient, 2 symptomatic control patients with HRM and pH-impedance monitoring for reflux symptoms were identified within the same time frame; 15 asymptomatic healthy controls with HRM studies were also studied. Concurrent myotomy and preoperative diagnosis of obstructive motor disorders were exclusions. Conventional HRM metrics, esophagogastric junction (EGJ) pressures, contractile integral (EGJ-CI), acid exposure time (AET), and reflux episode numbers were extracted. Intragastric pressure was sampled at baseline, during swallows, and with straight leg raise maneuver, and compared with intraesophageal pressure and reflux burden.

RESULTS

Patient cohorts included 36 SG patients, 23 RYGB patients, 113 symptomatic controls, and 15 asymptomatic controls. While both SG and RYGB patients pressurized the stomach during swallows and straight leg raise, SG patients had higher AET (median 6.0% vs 0.2%), reflux episode numbers (median 63.0 vs 37.5), and baseline intragastric pressure (median 17.3 mm Hg vs 13.1 mm Hg) ( P < 0.001). SG patients also had lower trans-EGJ pressure gradients when reflux episodes were >80 or AET was >6.0% ( P = 0.018 and 0.08, respectively, compared with no pathologic reflux). On multivariable analysis, SG status and low EGJ-CI independently associated with AET and reflux episode numbers ( P ≤ 0.04).

DISCUSSION

Impaired EGJ barrier function and proximal gastric pressurization after SG are associated with gastroesophageal reflux, especially during strain maneuvers.

Climate Change and the Esophagus: Speculations on Changing Disease Patterns as the World Warms

PURPOSE OF REVIEW

Esophageal disorders, including gastroesophageal reflux disease (GERD), eosinophilic esophagitis (EoE), and esophageal cancer, may be affected by climate change. Our review describes the impact of climate change on risk factors associated with esophageal diseases and speculates how these climate-related factors impacted esophageal disorders and their management.

RECENT FINDINGS

Climate change is responsible for extreme weather conditions (shifts in rainfall, floods, droughts, and forest fires) and global warming. These consequences affect basic human needs of water and food, causing changes in population dynamics and pose significant threats to digestive health, including common esophageal disorders like GERD, EoE, and esophageal cancers. The changing patterns of esophageal diseases with climate change are likely mediated through risk factors, including nutrition, pollutants, microplastics, and the microbiota-gut-brain axis. The healthcare process itself, including GI endoscopy practices commonly employed in diagnosing and therapeutics of esophageal diseases, may, in turn, contribute to climate change through plastic wastage and greenhouse gas emissions, thus creating the climate change lifecycle. Breaking the cycle would involve changes at the individual level, community level, and national policy level. Prevention is key, with individuals identifying and remediating risk factors and reducing carbon footprints. The ABC (Advocacy, Broadcast, and Collaborate) activities would help enhance awareness at the community level. Higher-level programs such as the Bracing Resilience Against Climate Effects (BRACE) would lead to broader and larger-scale adoption of public health adaptation strategies at the national level. The impact of climate change on esophageal disorders is likely real, mediated by several risk factors, and creates a climate change lifecycle that may only break if changes are made at individual, community, and national levels.

Study of gastroesophageal reflux. Interpretation of functional tests in the obese patient

Overweight and obesity are a public health problem and in 1997 obesity was recognized as a global epidemic by the World Health Organization (WHO). Overweight and obesity affect almost 60% of adults and one in three children in Europe according to the most recent WHO report. Objectively, gastroesophageal reflux disease (GERD) is defined as the presence of characteristic esophageal mucosal damage assessed by endoscopy and/or the demonstra-tion of pathological acid exposure by reflux monitoring studies. The prevalence of GERD is increased in obese patients In overweight and obese patients, the clinical symptoms of GERD are especially present in the supine position and this correlates with more frequent episodes of nocturnal reflux in the 24-h pH monitoring, there is also an increase in the number of refluxes with content acid. In the population with symptoms, digestive endoscopy detects data of erosive esophagitis in 50% of patients, while 24-h pH-impedanciometry diagnoses 92% of patients with non-erosive reflux disease (NERD) The presence of persistent GERD in the mucosa affects esophageal motility and patients may develop ineffective esophageal motility-type disorders, so we will review the interpre-tation of the functional tests that determine motility, which is esophageal manometry, and those that determine reflux gastroesophageal, acid and non-acid, which is the pH measure-ment with or without 24-h impedanciometry.

Transient Hiatal Separation During Straight Leg Raise Can Predict Reflux Burden in Gastroesophageal Reflux Disease Patients With Ineffective Esophageal Motility

Background/Aims

Straight leg raise (SLR) can be utilized to evaluate the integrity of the esophagogastric junction during high-resolution manometry (HRM). We aim to assess the value of transient hiatal separation during SLR in symptomatic reflux patients.

Methods

Consecutive reflux patients undergoing esophageal HRM and pH monitoring were included. Transient hiatal separation was defined by a ≥ 1 cm separation between the lower esophageal sphincter and crural diaphragm during SLR. We compared esophageal motor patterns and reflux monitoring parameters between patients with normal, transiently abnormal and consistently abnormal esophagogastric junction morphology during SLR.

Results

Of 85 (56.3% female, mean age: 46.7 ± 12.3 years) completed SLR, esophagogastric junction morphology was normal in 31 (36.5%), transient hiatal separation in 19 (22.3%), and consistently hiatal hernia in 35 (41.2%). The values of total acid exposure time (P = 0.016), longest acid reflux episodes (P = 0.024), and DeMeester scores (P = 0.016) were higher in hiatal hernia compared to patients with non-transient hiatal separation, but there were no differences between those with and without transient hiatal separation. Within ineffective esophageal motility, the presence of transient hiatal separation during SLR significantly associated with a higher total acid exposure time (P = 0.014), higher DeMeester scores (P = 0.019), higher total acid reflux events (P = 0.037), and higher longest acid reflux episodes (P = 0.006).

Conclusion

Our work suggests that SLR may have value as a provocative test during HRM, and future outcome studies are warranted to elucidate the clinical relevance of motor abnormalities depicted from SLR.

Consensus statements and recommendations on the management of mild-to-moderate gastroesophageal reflux disease in the Southeast Asian region

This paper reports the proceedings from the first consensus meeting on the management of mild-to-moderate gastroesophageal reflux disease (GERD) in the Southeast Asian (SEA) region. Seventeen statements were drawn up by a steering committee that focused on epidemiology, mechanism of action, diagnostic investigations, and treatment. Voting on the recommendations used the Delphi method with two rounds of voting among the 10 panel members. The consensus panel agreed that GERD is mostly a mild disease in the SEA region with predominantly non-erosive reflux disease (NERD). Complicated GERD and Barrett's esophagus are infrequently seen. The panel recommended endoscopy in patients with alarm or refractory symptoms but cautioned that the incidence of gastric cancer is higher in SEA. pH and impedance measurements were not recommended for routine assessment. The acid pocket is recognized as an important pathogenic factor in GERD. Lifestyle measures such as weight reduction, avoidance of smoking, reduction of alcohol intake, and elevation of the head of the bed were recommended but strict avoidance of specific foods or drinks was not. Alginates was recommended as the first-line treatment for patients with mild-to-moderate GERD while recognizing that proton-pump inhibitors (PPIs) remained the mainstay of treatment of GERD. The use of alginates was also recommended as adjunctive therapy when GERD symptoms were only partially responsive to PPIs.

Immune system and microbiome in the esophagus: implications for understanding inflammatory diseases

The gastrointestinal tract is the largest compartment of the body's immune system exposed to microorganisms, structural components and metabolites, antigens derived from the diet, and pathogens. Most studies have focused on immune responses in the stomach, the small intestine, and the colon, but the esophagus has remained an understudied anatomic immune segment. Here, we discuss the esophagus' anatomical and physiological distinctions that may account for inflammatory esophageal diseases.

Clinical characteristics and risk factors of gastroesophageal reflux disease in Vietnamese patients with upper gastrointestinal symptoms undergoing esophagogastroduodenoscopy

Background and Aim

The risk factors associated with the increase in prevalence of gastroesophageal reflux disease (GERD) are not consistent across countries and there have been few studies in Asia in the past 10 years. This study was conducted to assess the features and risk factors of GERD in Vietnamese patients.

Methods

A cross-sectional study was conducted on 1947 out-patients ≥18 years of age who were presented with upper gastrointestinal symptoms and underwent esophagogastroduodenoscopy. Reflux esophagitis was graded according to the Los Angeles classification. Endoscopically suspected Barrett's esophagus (BE) was recorded according to the Prague C and M criteria and biopsy was taken for histologic examination.

Results

There were 511 (26.2%) patients with GERD, 242 (47.4%) with nonerosive reflux disease, and 269 (52.6%) with reflux esophagitis and/or BE. Epigastric pain, regurgitation, and heartburn were the chief complaints in 36.8%, 27.0%, and 9.2% of patients, respectively. Most of the patients with mucosal injury had reflux esophagitis in mild grade and BE in the form of C0M ≤2 (99.6%, 231/232 and 97.8%, 46/47, respectively). In multivariate analysis, hiatal hernia, male gender, waist-to-hip ratio (independent from general obesity), and smoking were risk factors for GERD while Helicobacter pylori infection was negatively associated with GERD.

Conclusions

The majority of GERD patients had none or mild mucosal injury. Typical reflux symptoms, however, may not be the chief complaints. Central obesity would be more important than general obesity as a risk factor, while H. pylori infection was a "protective" factor for GERD in Vietnamese patients.

Application of a novel straight leg raise test during high-resolution manometry can predict esophageal contractile reserve in patients with gastroesophageal reflux disease

BACKGROUND/AIM

Increased intra-abdominal pressure from abdominal compression augments esophageal peristalsis during high-resolution manometry (HRM), and straight leg raise (SLR) while supine increases intra-abdominal pressure. We determined if water swallows performed during SLR can mimic contraction reserve seen with multiple rapid swallows (MRS).

METHODS

Consecutive patients evaluated for GERD symptoms completed validated GERD questionnaires, esophageal HRM, and upper endoscopy. Distal contractile integral (DCI) was analyzed during single water swallows (10 × 5 mL), MRS (5 × 2 mL), and during SLR (5x5 mL). Peristaltic breaks were measured using software tools with a 20 mm Hg isobaric contour. Univariate correlational analyses were performed to compare esophageal motor patterns and DCI values during single water swallows, MRS, and SLR.

RESULTS

Of 103 study patients (mean age: 46.7 ± 12.3 years, 56.3% female), 50 (48.5%) had ineffective esophageal motility (IEM). Contraction reserve was observed on MRS in 62% with IEM, and 35.8% with normal motility (p = 0.008). DCI was significantly higher during SLR compared to mean single swallow DCI in both IEM and normal motility patients (p < 0.001 for each comparison). In IEM patients, SLR significantly reduced swallows with peristaltic breaks (6.1 ± 3.7 vs 3.6 ± 3.6; p < 0.001) and shortened the length of the largest break (4.8 ± 3.4 vs 3.0 ± 3.0 cm; p < 0.001). DCI response following MRS correlated with DCI with swallows during SLR, with a correlational coefficient (Pearson's r) of 0.70 (p < 0.001).

CONCLUSIONS

Swallowing against the resistance of increased intra-abdominal pressure from SLR improves esophageal body peristaltic performance and predicts esophageal body contraction reserve.

Evaluation of the Esophagogastric Junction on High Resolution Manometry

The esophagogastric junction (EGJ) is a complex barrier between the thoracic and abdominal luminal gut compartments, comprised primarily of the lower esophageal sphincter (LES) and crural diaphragm. Although closed at rest, the EGJ relaxes to allow antegrade bolus transit and retrograde venting of air. Abnormal relaxation is the hallmark of achalasia spectrum disorders, while increased frequency of transient lower esophageal sphincter relaxations and/or EGJ disruption are seen in gastroesophageal reflux disease. High resolution manometry (HRM) is the modern day gold standard for assessment of EGJ morphology and function, with better performance characteristics compared with endoscopy and barium esophagography. Conventional LES metrics defining EGJ function include resting LES pressure as well as postswallow residual pressures. Newer HRM-based metrics include EGJ contractile integral, which measures static barrier function at rest, and EGJ morphology, which characterizes the relationship between LES and crural diaphragm. Provocative maneuvers assess dynamic EGJ function during physiological or pharmacologic stress. The most useful of these maneuvers, the rapid drink challenge, assesses for latent obstruction, while multiple rapid swallows evaluate adequacy of deglutitive inhibition. Amyl nitrate and cholecystokinin administration can segregate motor from structural obstruction. Newer provocative tests (straight leg raise maneuver, abdominal compression) and novel diagnostic tools (functional lumen imaging probe) complement HRM evaluation of the EGJ. Although current HRM metrics and maneuvers show promise in identifying clinically relevant EGJ abnormalities, future investigations evaluating management outcomes will improve segregation of normal from abnormal EGJ morphology and function.

Straight leg raise metrics on high-resolution manometry associate with esophageal reflux burden

BACKGROUND

Straight leg raise (SLR) is a provocative maneuver that assesses esophagogastric junction (EGJ) barrier function during high-resolution manometry (HRM). We evaluated the value of SLR in symptomatic reflux patients undergoing ambulatory reflux monitoring.

METHODS

Adult patients being evaluated for reflux symptoms with esophageal physiologic testing off antisecretory therapy over a 12 month period were studied. Demographics, clinical presentation, HRM studies, and reflux monitoring studies were analyzed. Intra-abdominal and intra-esophageal pressures were extracted at baseline and during SLR from HRM studies. Acid exposure time (AET) was derived from reflux monitoring studies, and EGJ morphology and tone from HRM studies. SLR pressure metrics predicting abnormal AET were evaluated.

KEY RESULTS

Of 122 patients, 70 (57.4%) had ≥50% peak intra-abdominal pressure increase during SLR (58.0 ± 1.4 years, 75.7% female). Peak intra-esophageal pressure gradient between baseline and SLR predicted pathologic AET when ≥100% (AUC 0.78, sensitivity 71%, specificity 75%, P < .001), seen in 60.7% with AET > 6%, but only 23.7% with AET < 4% (P = .01). Peak intra-esophageal pressure gradient ≥100% was most discriminative in identifying abnormal acid burden in type 1 EGJ morphology (P = .005) but trended toward significance in type 2 and type 3 morphology (P = .1). Normal and abnormal EGJ contractile integral did not associate with peak intra-esophageal pressure gradient either collectively or when subdivided by EGJ morphology (P ≥ .2).

CONCLUSIONS & INFERENCES

Analysis of intra-esophageal pressure gradients during SLR, a simple HRM maneuver, may augment evaluation of symptomatic GERD, and provide adjunctive evidence supporting GERD.

Randomised clinical trial: the effectiveness of Gaviscon Advance vs non-alginate antacid in suppression of acid pocket and post-prandial reflux in obese individuals after late-night supper

BACKGROUND

Late-night supper increases the risk of postprandial reflux from the acid pocket especially in obesity. An alginate-based, raft-forming medication may be useful for obese patients with GERD.

AIMS

To compare the efficacy of Gaviscon Advance (Reckitt Benckiser, UK) and a non-alginate antacid in post-supper suppression of the acid pocket and post-prandial reflux among obese participants.

METHODS

Participants underwent 48 h wireless and probe-based pH-metry recording of the acid pocket and lower oesophagus, respectively, and were randomised to single post-supper (10 pm) dose of either Gaviscon Advance or a non-alginate antacid on the second night. Primary outcomes were suppression of median pH of acid pocket and lower oesophagus, measured every 10-minutes post-supper for 1 h. Secondary outcomes were suppression of % time pH < 4 at lower oesophagus and improvement in frequency and visual analogue score (VAS) of regurgitation.

RESULTS

Of the 81 screened participants, 55 were excluded and 26 (mean age 33.5 years, males 77.8% and BMI 32.8 kg/m² ) were randomised to Gaviscon Advance (n = 13) or antacid (n = 13). Median pH of the acid pocket but not the lower oesophagus was suppressed with Gaviscon Advance vs antacid (all P < 0.04) Gaviscon Advance but not antacid significantly reduced in % time pH < 4, symptom frequency and VAS on day 2 vs day 1 (all P < 0.05).

CONCLUSIONS

Among obese individuals, Gaviscon Advance was superior to a non-alginate antacid in post-supper suppression of the acid pocket. (Clinical trial registration unique identifier: NCT03516188).

Clinical course of gastroesophageal reflux disease and impact of treatment in symptomatic young patients

In symptomatic young patients with gastroesophageal reflux symptoms, early identification of progressive gastroesophageal reflux disease (GERD) is critical to prevent long-term complications associated with hiatal hernia, increased esophageal acid and nonacid exposure, release of proinflammatory cytokines, and development of intestinal metaplasia, endoscopically visible Barrett's esophagus, and dysplasia leading to esophageal adenocarcinoma. Progression of GERD may occur in asymptomatic patients and in those under continuous acid-suppressive medication. The long-term side effects of proton-pump inhibitors, chemopreventive agents, and radiofrequency ablation are contentious. In patients with early-stage disease, when the lower esophageal sphincter function is still preserved and before endoscopically visible Barrett's esophagus develops, novel laparoscopic procedures, such as magnetic and electric sphincter augmentation, may have a greater role than conventional surgical therapy. A multidisciplinary approach to GERD by a dedicated team of gastroenterologists and surgeons might impact the patients' lifestyle, the therapeutic choices, and the course of the disease. Biological markers are needed to precisely assess the risk of disease progression and to tailor surveillance, ablation, and management.

Risk factors predisposing to cardia gastric adenocarcinoma: Insights and new perspectives

Recent decades have seen an alarming increase in the incidence of cardia gastric adenocarcinoma (CGA) while noncardia gastric adenocarcinoma (NCGA) has decreased. In 2012, 260 000 CGA cases (age‐standardised rate (ASR); 3.3/100 000) and 691 000 NCGA cases (ASR; 8.8/100 000) were reported worldwide. Compared with women, men had greater rates for both the subsites, especially for CGA. Recently, four molecular subtypes of GC have been proposed by the Cancer Genome Atlas (TCGA) and the Asian Cancer Research Group (ACRG); however, these classifications do not take into account predisposing germline variants and their possible interaction with somatic alterations in carcinogenesis. The etiology of adenocarcinoma of the cardia and the gastroesophageal junction (GEJ) is not known. It is thought that CGA is distinct from adenocarcinomas located in the esophagus or distal stomach, both epidemiologically and biologically. Moreover, CGA is often identified in the advanced stage having a poor prognosis. Therefore, understanding the risk and the role of predisposing factors in etiology of CGA can inform clinical practice and counseling for risk reduction. In this paper, we showed that GC family history, lifestyle, demographics, gastroesophageal reflux disease, Helicobacter pylori infection, and multiple genetic and epigenetic risk factors as well as several predisposing conditions may underlie susceptibility to CGA. However, several genome‐wide association studies (GWASs) should be conducted to identify novel high‐penetrance genes and pathways as well as causal germline variants predisposing to CGA. They must include different ethnic groups, especially from high‐incidence countries for CGA, because some risk loci are ancestry‐specific. In parallel, statistical methods can be developed to identify cancer predisposition genes (CPGs) from tumor sequencing data. It is also necessary to find novel long noncoding RNAs related to the risk of CGA. Taken altogether, new cancer risk prediction models, including all genetic and nongenetic factors influencing risk, should be developed to facilitate risk assessment, disease prevention, and early diagnosis and intervention of CGA in the future.

Sex Differences in the Relation between Waist Circumference within the Normal Range and Development of Reflux Esophagitis

We examined the association of abdominal obesity and waist circumference within normal range with the incidence of reflux esophagitis, separately in men and women. This cohort study involved 142,679 Korean adults without reflux esophagitis, who underwent upper endoscopy at baseline and during follow-up. Waist circumference was categorized into the following quartiles: <80, 80.1⁻85, 85.1⁻90, and ≥90.1 cm in men; and <69.3, 69.3⁻74, 74.1⁻79.5, and ≥79.6 cm in women. During the 551,877.8 person-years of follow-up, 29,509 participants developed reflux esophagitis. The association between waist circumference quartiles and risk of reflux esophagitis significantly differed with sex (p for interaction < 0.001). In men, multivariable-adjusted hazard ratios (HRs) (95% confidence intervals (CIs)) comparing waist circumference quartiles 2, 3, and 4 to the lowest quartile were 1.03 (0.99⁻1.07), 1.08 (1.04⁻1.12), and 1.15 (1.10⁻1.19), respectively. In women, HRs (95% CIs) comparing quartiles 1, 2, and 4 to the 3rd quartile were 1.10 (1.04⁻1.17), 1.03 (0.98⁻1.10), and 1.07 (1.01⁻1.13), respectively. In this large cohort with endoscopic follow-up, the risk of reflux esophagitis increased with increasing waist circumference even within the normal range in men, whereas the risk increased with low normal waist circumference or with abdominal obesity in women, indicating a U-shaped association.

Esophageal provocation tests: Are they useful to improve diagnostic yield of high resolution manometry?

High resolution manometry (HRM) is the gold standard to diagnose esophageal motility disorders but has some limitations. The inclusion of provocative tests might enhance the diagnostic yield of HRM. These tests are easy to perform and to add to the regular manometry protocol. Multiple rapid swallows (MRS; 5 2-mL swallows) is useful to assess the contractile reserve and deglutitive inhibition. The optimal number of MRS to perform might be 3 as suggested by Mauro et al. in this issue of Neurogastroenterology & Motility. The absence of contractile reserve might be associated with gastro-esophageal reflux disease and with an increased risk of post fundoplication dysphagia. Single viscous and solid swallows might enhance the detection of esophageal motility disorders but are not significantly associated with symptom occurrence. Test meal has the advantage to represent a real-life scenario and is promising to depict significant motility findings responsible for esophageal symptoms. Post-prandial recording might also be of interest to diagnose rumination and belching disorders. The best indication of rapid drink challenge test (free drinking of 200 mL) is currently the diagnosis of esophago-gastric junction obstruction. Finally, abdominal compression might be an option to evaluate response of esophageal peristalsis in a context of outflow resistance as proposed by Brink et al. in this issue. These provocative maneuvers appear to provide a complementary role in the evaluation of esophageal motility but require prospective studies to determine the validity of the findings and whether they will lead to changes in clinical practice.

Esophageal hiatal hernia: risk, diagnosis and management

Esophageal hiatal hernia involves abnormal abdominal entry into thoracic cavity. It is classified based on orientation between esophageal junction and diaphragm. Sliding hiatal hernia (Type-I) comprises the most frequent category, emanating from right crus of diaphragm. Type-II esophageal hernia engages both left and right muscular crura. Type-III and IV additionally include the left crus. Age and increased body mass index are key risk factors, and congenital skeletal aberrations trigger pathogenesis through intestinal malrotations. Familiar manifestations include gastric reflux, nausea, bloating, chest and epigastric discomfort, pharyngeal and esophageal expulsion and dysphagia. Weight loss and colorectal bleeding are severe symptoms. Areas covered: This review summarizes updated evidence of pathophysiology, risk factors, diagnosis and management of hiatal hernias. Laparoscopy and oesophagectomy procedures have been discussed as surgical procedures. Expert commentary: Endoscopy identifies untreatable gastric reflux; radiology is better for pre-operative assessments; manometry measures esophageal peristalsis, and CT scanning detects gastric volvulus and associated organ ruptures. Gastric reflux disease is mitigated using antacids and proton pump and histamine-2-receptor blockers. Severe abdominal penetration into chest cavity demands surgical approaches. Hence, esophagectomy has chances of post-operative morbidity, while minimally invasive laparoscopy entails fewer postoperative difficulties and better visualization of hernia and related vascular damages.

Waist to hip ratio is a better predictor of esophageal acid exposure than body mass index

BACKGROUND

Obesity and gastroesophageal reflux disease (GERD) are major health problems showing an inconstant relationship in the literature. Therefore, anthropometric parameters which are predictive and can simply be assessed at first patient presentation may lead to a better patient selection for ambulatory reflux monitoring. We aimed to examine the association of body mass index (BMI) and waist to hip ratio (WHR) with gastroesophageal reflux activity during 24 hour-pH-impedance monitoring.

METHODS

Seven hundred and seventy-one patients with GERD symptoms underwent 24 hour-pH-impedance monitoring and high resolution manometry off proton pump inhibitors. Patients with known primary motility disorders of the esophagus and pre-existing endoscopic or operative procedure on esophagus or stomach were excluded from the study. Reflux parameters and anthropometric and demographic data from our prospectively gathered database were analyzed. We performed univariate and multivariate regression analysis to evaluate the associations of BMI and WHR with reflux parameters measured with 24 hour-pH-impedance monitoring.

KEY RESULTS

WHR showed a significantly stronger association with esophageal acid exposure than BMI (P<.001). Our data show that 6.9% of the percentage of endoluminal pH<4 in the distal esophagus is attributable to WHR. Furthermore, an association of WHR with impaired esophageal acid clearance was observed. Additionally, we observed an inverse relationship between lower esophageal sphincter integrity (P=.05) and esophageal acid exposure.

CONCLUSIONS AND INFERENCES

WHR is a better predictor for esophageal acid exposure than BMI. Biomechanical and metabolic mechanisms of central fat distribution may influence reflux parameters in 24 hour pH impedance monitoring, which may affect patient selection for ambulatory reflux monitoring.

Abdominal Compression by Waist Belt Aggravates Gastroesophageal Reflux, Primarily by Impairing Esophageal Clearance

BACKGROUND & AIMS

Central obesity promotes gastroesophageal reflux, which may be related to increased intra-abdominal pressure. We investigated the effect of increasing abdominal pressure by waist belt on reflux in patients with reflux disease.

METHODS

We performed a prospective study of patients with esophagitis (n = 8) or Barrett's esophagus (n = 6); median age was 56 years and median body mass index was 26.8. Proton pump inhibitors were stopped at least 7 days before the study and H2 receptor antagonists were stopped for at least 24 hours before. The severity of upper GI symptoms was assessed and measurements of height, weight, and waist and hip circumference taken. Combined high-resolution pH measurement and manometry were performed in fasted state for 20 minutes and for 90 minutes following a standardized meal. The squamocolumnar junction was marked by endoscopically placed radiopaque clips. The procedures were performed with and without a waist belt (a weight-lifter belt applied tightly and inflated to a constant cuff pressure of 50 mmHg). We compared variables between groups using the Wilcoxon Signed Rank test and tested for correlations using Spearman Rho bivariate analysis.

RESULTS

Without the belt, intragastric pressure correlated with waist circumference (r = 0.682; P = .008), with the range in pressure between smallest and largest waist circumference being 15 mmHg. The belt increased intragastric pressure by a median of 6.9 mmHg during fasting (P = .002) and by 9.0 mmHg after the meal (P = .001). Gastroesophageal acid reflux at each of the pH sensors extending 5.5 cm proximal to the peak lower esophageal sphincter pressure point was increased by approximately 8-fold by the belt (all P < .05). Following the meal, the mean number of reflux events with the belt was 4, vs 2 without (P = .008). Transient lower esophageal sphincter relaxations were not increased by the belt, but those associated with reflux were increased (2 vs 3.5; P = .04). The most marked effect of the belt was impaired esophageal clearance of refluxed acid (median values of 23.0 seconds without belt vs 81.1 seconds with belt) (P = .008). The pattern of impaired clearance was that of rapid re-reflux after peristaltic clearance.

CONCLUSIONS

In a prospective study of patients with esophagitis or Barrett's esophagus, we found belt compression increased acid reflux following a meal. The intragastric pressure rise inducing this effect is well within the range associated with differing waist circumference and likely to be relevant to the association between obesity and reflux disease.

Different time trend and management of esophagogastric junction adenocarcinoma in three Asian countries

Esophagogastric junction (EGJ) adenocarcinoma has been on the increase in Western countries. However, in Asian countries, data on the incidence of EGJ adenocarcinoma are evidently lacking. In the present review, we focus on the current clinical situation of EGJ adenocarcinoma in three Asian countries: Japan, Hong Kong, and Malaysia. The incidence of EGJ adenocarcinoma has been reported to be gradually increasing in Malaysia and Japan, whereas it has stabilized in Hong Kong. However, the number of cases in these countries is comparatively low compared with Western countries. A reason for the reported difference in the incidence and time trend of EGJ adenocarcinoma among the three countries may be explained by two distinct etiologies: one arising from chronic gastritis similar to distal gastric cancer, and the other related to gastroesophageal reflux disease similar to esophageal adenocarcinoma including Barrett's adenocarcinoma. This review also shows that there are several concerns in clinical practice for EGJ adenocarcinoma. In Hong Kong and Malaysia, many EGJ adenocarcinomas have been detected at a stage not amenable to endoscopic resection. In Japan, histological curability criteria for endoscopic resection cases have not been established. We suggest that an international collaborative study using the same definition of EGJ adenocarcinoma may be helpful not only for clarifying the characteristics of these cancers but also for improving the clinical outcome of these patients.

Association between Increased Gastric Juice Acidity and Sliding Hiatal Hernia Development in Humans

Objectives

Several clinical factors; overweight, male gender and increasing age, have been implicated as the etiology of hiatal hernia. Esophageal shortening due to acid perfusion in the lower esophagus has been suggested as the etiological mechanism. However, little is known about the correlation between gastric acidity and sliding hiatus hernia formation. This study examined whether increased gastric acid secretion is associated with an endoscopic diagnosis of hiatal hernia.

Methods

A total of 286 consecutive asymptomatic patients (64 were diagnosed as having a hiatal hernia) who underwent upper gastrointestinal endoscopy were studied. Clinical findings including fasting gastric juice pH as an indicator of acid secretion, age, sex, body mass index, and Helicobacter pylori infection status determined by both Helicobacter pylori serology and pepsinogen status, were evaluated to identify predictors in subjects with hiatal hernia.

Results

Male gender, obesity with a body mass index >25, and fasting gastric juice pH were significantly different between subjects with and without hiatal hernia. The cut-off point of fasting gastric juice pH determined by receiver operating curve analysis was 2.1. Multivariate regression analyses using these variables, and age, which is known to be associated with hiatal hernia, revealed that increased gastric acid secretion with fasting gastric juice pH <2.1 (OR = 2.60, 95% CI: 1.38–4.90) was independently associated with hiatal hernia. Moreover, previously reported risk factors including male gender (OR = 2.32, 95% CI: 1.23–4.35), body mass index >25 (OR = 3.49, 95% CI: 1.77–6.91) and age >65 years (OR = 1.86, 95% CI: 1.00–3.45), were also significantly associated with hiatal hernia.

Conclusions

This study suggests that increased gastric acid secretion independently induces the development of hiatal hernia in humans. These results are in accordance with the previously reported hypothesis that high gastric acid itself induces hiatal hernia development.

The effect of different types of abdominal binders on intra-abdominal pressure

Objectives:

To investigate the effect of non-elastic/elastic abdominal binders on intra-vesical pressure (IVP), physiological functions, and clinical outcomes in laparotomy patients at the perioperative stage.

Methods:

This prospective study was conducted from May to October 2014 at the Trauma Surgery Department, Daping Hospital, Chongqing, China. Laparotomy patients were randomly divided into non-elastic abdominal binder group (28 patients), and elastic abdominal binder group (29 patients). Binders were applied for 14 days following the operation, or until discharge. Demographic information, Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation II (APACHE-II) scores (prior to the operation, on the first day after operation, the day IVP measurement was stopped, and one day before discharge), and outcomes were recorded. The IVP was measured before the operation to postoperative day 7.

Results:

There were no significant differences in the demographic information, outcomes, SOFA or APACHE-II scores between the 2 groups. Initial out-of-bed mobilization occurred earlier in the elastic binder group (3.2 ± 2.0 versus 5.0 ± 3.7 days, p=0.028). A greater increase in IVP was observed in the non-elastic binder group than in the elastic binder group (2.9 ± 1.1 versus 1.1 ± 0.7 mm Hg, p=0.000).

Conclusion:

Elastic binders have relatively little effect on IVP and are more helpful at promoting postoperative recovery than non-elastic binders. Therefore, elastic binders are more suitable for clinical use.

In healthy volunteers, immunohistochemistry supports squamous to columnar metaplasia as mechanism of expansion of cardia, aggravated by central obesity

INTRODUCTION

Recently, we showed that the length of cardiac mucosa in healthy volunteers correlated with age and obesity. We have now examined the immunohistological characteristics of this expanded cardia to determine whether it may be due to columnar metaplasia of the distal oesophagus.

METHODS

We used the squamocolumnar junction (SCJ), antral and body biopsies from the 52 Helicobacter pylori-negative healthy volunteers who had participated in our earlier physiological study and did not have hiatus hernia, transsphincteric acid reflux, Barrett's oesophagus or intestinal metaplasia (IM) at cardia. The densities of inflammatory cells and reactive atypia were scored at squamous, cardiac and oxyntocardiac mucosa of SCJ, antrum and body. Slides were stained for caudal type homeobox 2 (CDX-2), villin, trefoil factor family 3 (TFF-3) and liver-intestine (LI)-cadherin, mucin MUC1, Muc-2 and Muc-5ac. In addition, biopsies from 15 Barrett's patients with/without IM were stained and scored as comparison. Immunohistological characteristics were correlated with parameters of obesity and high-resolution pH metry recording.

RESULTS

Cardiac mucosa had a similar intensity of inflammatory infiltrate to non-IM Barrett's and greater than any of the other upper GI mucosae. The immunostaining pattern of cardiac mucosa most closely resembled non-IM Barrett's showing only slightly weaker CDX-2 immunostaining. In distal oesophageal squamous mucosa, expression of markers of columnar differentiation (TFF-3 and LI-cadherin) was apparent and these correlated with central obesity (correlation coefficient (CC)=0.604, p=0.001 and CC=0.462, p=0.002, respectively). In addition, expression of TFF-3 in distal oesophageal squamous mucosa correlated with proximal extension of gastric acidity within the region of the lower oesophageal sphincter (CC=-0.538, p=0.001).

CONCLUSIONS

These findings are consistent with expansion of cardia in healthy volunteers occurring by squamo columnar metaplasia of distal oesophagus and aggravated by central obesity. This metaplastic origin of expanded cardia may be relevant to the substantial proportion of cardia adenocarcinomas unattributable to H. pylori or transsphincteric acid reflux.

Pathophysiology of gastroesophageal reflux disease: new understanding in a new era

BACKGROUND

The prevalence of gastroesophageal reflux disease (GERD) has increased in the last decades and it is now one of the most common chronic diseases. Throughout time our insight in the pathophysiology of GERD has been characterized by remarkable back and forth swings, often prompted by new investigational techniques. Even today, the pathophysiology of GERD is not fully understood but it is now recognized to be a multifactorial disease. Among the factors that have been shown to be involved in the provocation or increase of reflux, are sliding hiatus hernia, low lower esophageal sphincter pressure, transient lower esophageal sphincter relaxation, the acid pocket, obesity, increased distensibility of the esophagogastric junction, prolonged esophageal clearance, and delayed gastric emptying. Moreover, multiple mechanisms influence the perception of GERD symptoms, such as the acidity of the refluxate, its proximal extent, the presence of gas in the refluxate, duodenogastroesophageal reflux, longitudinal muscle contraction, mucosal integrity, and peripheral and central sensitization. Understanding the pathophysiology of GERD is important for future targets for therapy as proton pump inhibitor-refractory GERD symptoms remain a common problem.

PURPOSE

In this review we provide an overview of the mechanisms leading to reflux and the factors influencing perception, in the light of historical developments. It is clear that further research remains necessary despite the recent advances in the understanding of the pathophysiology of GERD.

Republished: symptomatic reflux disease: the present, the past and the future

The worldwide incidence of GORD and its complications is increasing along with the exponentially increasing problem of obesity. Of particular concern is the relationship between central adiposity and GORD complications, including oesophageal adenocarcinoma. Driven by progressive insight into the epidemiology and pathophysiology of GORD, the earlier belief that increased gastroesophageal reflux mainly results from one dominant mechanism has been replaced by acceptance that GORD is multifactorial. Instigating factors, such as obesity, age, genetics, pregnancy and trauma may all contribute to mechanical impairment of the oesophagogastric junction resulting in pathological reflux and accompanying syndromes. Progression of the disease by exacerbating and perpetuating factors such as obesity, neuromuscular dysfunction and oesophageal fibrosis ultimately lead to development of an overt hiatal hernia. The latter is now accepted as a central player, impacting on most mechanisms underlying gastroesophageal reflux (low sphincter pressure, transient lower oesophageal sphincter relaxation, oesophageal clearance and acid pocket position), explaining its association with more severe disease and mucosal damage. Since the introduction of proton pump inhibitors (PPI), clinical management of GORD has markedly changed, shifting the therapeutic challenge from mucosal healing to reduction of PPI-resistant symptoms. In parallel, it became clear that reflux symptoms may result from weakly acidic or non-acid reflux, insight that has triggered the search for new compounds or minimally invasive procedures to reduce all types of reflux. In summary, our view on GORD has evolved enormously compared to that of the past, and without doubt will impact on how to deal with GORD in the future.

Two distinct etiologies of gastric cardia adenocarcinoma: interactions among pH, Helicobacter pylori, and bile acids

Gastric cancer can be classified as cardia and non-cardia subtypes according to the anatomic site. Although the gastric cancer incidence has decreased steadily in several countries over the past 50 years, the incidence of cardia cancers and esophageal adenocarcinoma (EAC) continue to increase. The etiological factors involved in the development of both cardia cancers and EACs are associated with high animal fat intake, which causes severe obesity. Central obesity plays roles in cardiac-type mucosa lengthening and partial hiatus hernia development. There are two distinct etiologies of cardia cancer subtypes: one associated with gastroesophageal reflux (GER), which predominantly occurs in patients without Helicobacter pylori (H. pylori) infection and resembles EAC, and the other associated with H. pylori atrophic gastritis, which resembles non-cardia cancer. The former can be developed in the environment of high volume duodenal content reflux, including bile acids and a higher acid production in H. pylori-negative patients. N-nitroso compounds, which are generated from the refluxate that includes a large volume of bile acids and are stabilized in the stomach (which has high levels of gastric acid), play a pivotal role in this carcinogenesis. The latter can be associated with the changing colonization of H. pylori from the distal to the proximal stomach with atrophic gastritis because a high concentration of soluble bile acids in an environment of low acid production is likely to act as a bactericide or chemorepellent for H. pylori in the distal stomach. The manuscript introduces new insights in causative factors of adenocarcinoma of the cardia about the role of bile acids in gastro-esophageal refluxate based upon robust evidences supporting interactions among pH, H. pylori, and bile acids.

Mechanisms of Barrett's oesophagus (clinical): LOS dysfunction, hiatal hernia, peristaltic defects

Barrett's oesophagus, with the potential to develop into oesophageal adenocarcinoma (OAC), is a major complication of gastrooesophageal reflux disease (GORD). However, about 50% of patients developing OAC had no known GORD beforehand. Hence, while GORD symptoms, oesophagitis, and Barrett's have a number of common determinants (oesophagogastric junction (OGJ) incompetence, impaired oesophageal clearance mechanisms, hiatus hernia) they also have some independent determinants. Further, although excess oesophageal acid exposure plays a major role in the genesis of long-segment Barrett's oesophagus there is minimal evidence supporting this for short-segment Barrett's. Hence, these may have unique pathophysiological features as well. Long-segment Barrett's seems to share most, if not all, of the risk factors for oesophagitis, particularly high-grade oesophagitis. However, it is uncertain if OGJ function and acid clearance are more severely impaired in patients with long-segment Barrett's compared to patients with high-grade oesophagitis. With respect to short-segment Barrett's, the acid pocket may play an important pathogenic role. Conceptually, extension of the acid pocket into the distal oesophagus, also known as intra-sphincteric reflux, provides a mechanism or acid exposure of the distal osophageal mucosa without the occurrence of discrete reflux events, which are more likely to prompt reflux symptoms and lead to the development of oesophagitis. Hence, intra-sphincteric reflux related to extension of the acid/no acid interface at the proximal margin of the acid pocket may be key in the development of short segment Barrett's. However, currently this is still somewhat speculative and further studies are required to confirm this.

The role of obesity in oesophageal cancer development

The incidence of oesophageal adenocarcinoma has increased dramatically in the developed world in the last half century. Over approximately the same period there has been an increase in the prevalence of obesity. Multiple epidemiological studies and meta-analyses have confirmed that obesity, especially abdominal, visceral obesity, is a risk factor for gastro-oesophageal reflux, Barrett's oesophagus and oesophageal adenocarcinoma. Although visceral obesity enhances gastro-oesophageal reflux, the available data also show that visceral obesity increases the risk of Barrett's oesophagus and adenocarcinoma via reflux-independent mechanisms. Several possible mechanisms could link obesity with the risk of oesophageal adenocarcinoma in addition to mechanical effects increasing reflux. These include reduced gastric Helicobacter pylori infection, altered intestinal microbiome, factors related to lifestyle, the metabolic syndrome and associated low-grade inflammation induced by obesity and the secretion of mediators by adipocytes which may directly influence the oesophageal epithelium. Of these adipocyte-derived mediators, increased leptin levels have been independently associated with progression to oesophageal adenocarcinoma and in laboratory studies leptin enhances malignant behaviours in cell lines. Adiponectin is also secreted by adipocytes and levels decline with obesity: decreased serum adiponectin levels are associated with malignant progression in Barrett's oesophagus and experimentally adiponectin exerts anticancer effects in Barrett's cell lines and inhibits growth factor signalling. At present there are no proven chemopreventative interventions that may reduce the incidence of obesity-associated oesophageal cancer: observational studies suggest that the combined use of a statin and aspirin or another cyclo-oxygenase inhibitor is associated with a significantly reduced cancer incidence in patients with Barrett's oesophagus.

Pathophysiology of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is one of the most common digestive diseases in the Western world, with typical symptoms, such as heartburn, regurgitation, or retrosternal pain, reported by 15% to 20% of the general population. The pathophysiology of GERD is multifactorial. Our understanding of these factors has significantly improved in recent years, with increased understanding of the acid pocket and hiatal hernia and how these factors interact. Although our insight has significantly increased over the past years, more studies are required to better understand symptom generation in GERD, especially in patients with therapy-resistant symptoms.