Characteristics of symptomatic reflux episodes on Acid suppressive therapy

A scientometrics analysis and visualization of refractory gastroesophageal reflux disease

Background

Refractory gastroesophageal reflux disease (refractory GERD) is a heterogeneous disease characterized by unresponsiveness or poor efficacy to proton-pump inhibitors (PPIs). This chronic disorder substantially weakens patients' mental wellbeing and quality of life, increasing the financial burden on society. Multiple articles have been reported in this area. However, literature involving scientometric analysis of refractory GERD is absent. Therefore, it is necessary to understand the evolution of research themes and the main hotspots of refractory GERD through bibliometric methods.

Methods

All documents related to refractory GERD based on the WOS Core Collection from January 2000 to November 2023 were selected for analysis. Citespace V 6.1 R6, VOSviewer V 1.6.20, and Scimago Graphica V 1.0.38 were used to perform bibliometric analysis.

Results

We collected a total of 241 research articles from 36 countries and 322 institutions, contributed by over 1,000 authors. Over the last 20 years, the number of articles in this field has increased year by year, and since 2011, the number of publications has increased dramatically, with 85.89% of the papers. These countries are led by the United States and Japan. GUT had the highest number of citations and DIGESTION had the highest number of publications. Research on standardized diagnosis and management, mechanisms, novel monitoring methods, and innovative drugs and procedures for refractory GERD are the main topics and hotspots in this field. This study also found that neuroimmune interaction is closely related to refractory GERD, which may be a new direction for future mechanism research.

Conclusion

Our study is the first bibliometric analysis of the global literature on refractory GERD. This research provides valuable insights for researchers, enabling them to quickly understand the research frontier and hot topics of this field.

Pepsin Inhibitors Prevent Inflammation and Loss of Laryngeal Barrier Function in Mice with Gastroesophageal Reflux

OBJECTIVE

This study aimed to evaluate the role of pepsin inhibitors in the inflammatory response and their effects on laryngeal mucosal integrity during gastroesophageal reflux (GERD) under in vivo conditions.

METHODS

A surgical model of GERD was used, in which mice were treated with pepstatin (0.3 mg/kg) or darunavir (8.6 mg/kg) for 3 days. On the third day after the experimental protocol, the laryngeal samples were collected to assess the severity of inflammation (wet weight and myeloperoxidase activity) and mucosal integrity (transepithelial electrical resistance and paracellular epithelial permeability to fluorescein).

RESULTS

The surgical GERD model was reproduced. It showed features of inflammation and loss of barrier function in the laryngeal mucosa. Pepstatin and darunavir administration suppressed laryngeal inflammation and preserved laryngeal mucosal integrity.

CONCLUSION

Pepsin inhibition by the administration of pepstatin and darunavir improved inflammation and protected the laryngeal mucosa in a mouse experimental model of GERD.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:3080-3085, 2024.

Topic Modeling Analysis of Chinese Medicine Literature on Gastroesophageal Reflux Disease: Insights into Potential Treatment

OBJECTIVE

To analyze Chinese medicine (CM) prescriptions for gastroesophageal reflux disease (GERD), we model topics on GERD-related classical CM literature, providing insights into the potential treatment.

METHODS

Clinical guidelines were used to identify symptom terms for GERD, and CM literature from the database "Imedbooks" was retrieved for related prescriptions and their corresponding sources, indications, and other information. BERTopic was applied to identify the main topics and visualize the data.

RESULTS

A total of 36,207 entries are queried and 1,938 valid entries were acquired after manually filtering. Eight topics were identified by BERTopic, including digestion function abate, stomach flu, respiratory-related symptoms, gastric dysfunction, regurgitation and gastrointestinal dysfunction in pediatric patients, vomiting, stroke and alcohol accumulation are associated with the risk of GERD, vomiting and its causes, regurgitation, epigastric pain, and symptoms of heartburn.

CONCLUSIONS

Topic modeling provides an unbiased analysis of classical CM literature on GERD in a time-efficient and scale-efficient manner. Based on this analysis, we present a range of treatment options for relieving symptoms, including herbal remedies and non-pharmacological interventions such as acupuncture and dietary therapy.

Exploring the Substantive Significance of Laryngoscopic Observations as Reliable Prognostic Indicators for the Therapeutic Efficacy in Cases of Laryngopharyngeal Reflux

Laryngopharyngeal reflux (LPR) can be defined as the regurgitation of gastric acid and peptic substances into the laryngeal and hypopharyngeal regions, even in the case of a singular occurrence. A substantial body of recent research underscores the significance of non-acid reflux as a notable contributor to LPR symptoms. This current investigation delves into the assessment of laryngoscopic observations in their predictive capacity regarding the therapeutic outcomes of empirically administered proton pump inhibitor (PPI) therapy in the context of LPR. In this study, 145 patients who had received a clinical diagnosis of laryngopharyngeal reflux (LPR) underwent rigorous laryngoscopic examinations. These patients were subsequently categorized into three distinct groups based on the Belafsky reflux findings score, which included the criteria for normal (scores ranging from 0 to 7), mild to moderate (scores ranging from 8 to 16), and moderate to severe (scores ranging from 17 to 26). Among the participants, 12 individuals from the normal group, 44 from the mild to moderate group, and 31 from the moderate to severe group reported experiencing a noteworthy alleviation of symptoms following a three-month period of proton pump inhibitor (PPI) therapy and lifestyle adjustments. It is important to note that these findings yielded statistically significant results. Preliminary laryngoscopic observations hold significant potential as predictors of favourable treatment outcomes in the context of empirical proton pump inhibitor (PPI) therapy for laryngopharyngeal reflux (LPR).

Refractory Gastroesophageal Reflux Disease: Diagnosis and Management

Gastroesophageal reflux disease (GERD) is common, with increasing worldwide disease prevalence and high economic burden. A significant number of patients will remain symptomatic following an empiric proton pump inhibitor (PPI) trial. Persistent symptoms despite PPI therapy are often mislabeled as refractory GERD. For patients with no prior GERD evidence (unproven GERD), testing is performed off antisecretory therapy to identify objective evidence of pathologic reflux using criteria outlined by the Lyon consensus. In proven GERD, differentiation between refractory symptoms (persisting symptoms despite optimized antisecretory therapy) and refractory GERD (abnormal reflux metrics on ambulatory pH impedance monitoring and/or persistent erosive esophagitis on endoscopy while on optimized PPI therapy) can direct subsequent management. While refractory symptoms may arise from esophageal hypersensitivity or functional heartburn, proven refractory GERD requires personalization of the management approach, tapping from an array of non-pharmacologic, pharmacologic, endoscopic, and surgical interventions. Proper diagnosis and management of refractory GERD is critical to mitigate undesirable long-term complications such as strictures, Barrett's esophagus, and esophageal adenocarcinoma. This review outlines the diagnostic workup of patients presenting with refractory GERD symptoms, describes the distinction between unproven and proven GERD, and provides a comprehensive review of the current treatment strategies available for the management of refractory GERD.

Psychological Processes, Not Physiological Parameters, Are Most Important Contributors to Symptom Severity in Patients With Refractory Heartburn/Regurgitation Symptoms

BACKGROUND & AIMS

Physiological and psychological factors have been found to influence esophageal symptom reporting. We aimed to evaluate which of these factors are associated with 3 reflux symptom severity outcomes (ie, Total Reflux, Heartburn, and Sleep Disturbance) through a traditional statistical and a complementary machine-learning approach.

METHODS

Consecutive adult patients with refractory heartburn/regurgitation symptoms underwent standard 24-hour pH-impedance monitoring and completed questionnaires assessing past and current gastrointestinal and psychological health. In the traditional statistical approach, hierarchical general linear models assessed relationships of psychological and physiological variables (eg, total number of reflux episodes) with reflux severity scores. Mediation analyses further assessed pathways between relevant variables. In the machine-learning approach, all psychological and physiological variables were entered into 11 different models and cross-validated model performance was compared among the different models to select the best model.

RESULTS

Three hundred ninety-three participants (mean [SD] age, 48.5 [14.1] years; 60% were female) were included. General psychological functioning emerged as an important variable in the traditional statistical approach, as it was significantly associated with all 3 outcomes and mediated the relationship between childhood trauma and both Total Reflux and Heartburn Severity. In the machine-learning analyses, general psychological variables (eg, depressive symptoms) were most important for Total Reflux and Sleep Disturbance outcomes, and symptom-specific variables, like visceral anxiety, were more influential for Heartburn Severity. Physiological variables were not significant contributors to reflux symptom severity outcomes in our sample across reflux classifications and statistical methodology.

CONCLUSIONS

Psychological processes, both general and symptom-specific, should be considered as another important factor within the multifactorial processes that impact reflux symptom severity reporting across the reflux spectrum.

Psychological symptoms do not discriminate between reflux phenotypes along the organic-functional refractory GERD spectrum

OBJECTIVE

Historically, psychological processes are associated with disorders at the functional end of the gastro-oesophageal reflux disease (GERD) spectrum. However, recent research suggests that psychological symptoms are relevant across the entire GERD spectrum. We aim to investigate whether psychological symptoms are associated with reflux phenotype (True GERD, Borderline GERD, reflux hypersensitivity, functional heartburn) along the GERD spectrum in a cohort of refractory reflux patients.

DESIGN

Consecutive adult patients with refractory reflux symptoms underwent standard 24-hour pH-impedance monitoring and completed questionnaires assessing demographic, clinical and psychological information. Bayesian one-way analysis of variance assessed whether psychological variables differed across reflux phenotypes. Next, we applied multinomial and ordinal logistic regressions with clinical, demographic and psychological variables set as independent variables and reflux phenotype as the outcome variable. The complementary machine-learning approach entered all demographic, clinical and psychological variables into models, with reflux phenotype set nominally and ordinally. Cross-validated model performance was used to select the best model.

RESULTS

393 participants (mean (SD) age=48.5 (14.1); 60% female) were included. The Bayesian analyses found no difference in psychological variables across reflux phenotypes. Similarly, age, gender and proton pump inhibitor use were the only significant variables in the multinomial logistic regression and body mass index was significant in both regressions. Machine-learning analyses revealed poorly performing models with high misclassification rates (67-68%) in both models.

CONCLUSION

Psychological symptoms do not differ between nor predict reflux phenotype membership in refractory reflux patients. Findings suggest that psychological symptoms are relevant across the spectrum of GERD, rather than specific to functional oesophageal disorders.

Amprenavir inhibits pepsin-mediated laryngeal epithelial disruption and E-cadherin cleavage in vitro

Background

Laryngopharyngeal reflux (LPR) causes chronic cough, throat clearing, hoarseness, and dysphagia and can promote laryngeal carcinogenesis. More than 20% of the US population suffers from LPR and there is no effective medical therapy. Pepsin is a predominant source of damage during LPR which disrupts laryngeal barrier function potentially via E-cadherin cleavage proteolysis and downstream matrix metalloproteinase (MMP) dysregulation. Fosamprenavir (FDA-approved HIV therapeutic and prodrug of amprenavir) is a pepsin-inhibiting LPR therapeutic candidate shown to rescue damage in an LPR mouse model. This study aimed to examine amprenavir protection against laryngeal monolayer disruption and related E-cadherin proteolysis and MMP dysregulation in vitro.

Methods

Laryngeal (TVC HPV) cells were exposed to buffered saline, pH 7.4 or pH 4 ± 1 mg/mL pepsin ± amprenavir (10-60 min). Analysis was performed by microscopy, Western blot, and real time polymerase chain reaction (qPCR).

Results

Amprenavir (1 μM) rescued pepsin acid-mediated cell dissociation (p < .05). Pepsin acid caused E-cadherin cleavage indicative of regulated intramembrane proteolysis (RIP) and increased MMP-1,3,7,9,14 24-h postexposure (p < .05). Acid alone did not cause cell dissociation or E-cadherin cleavage. Amprenavir (10 μM) protected against E-cadherin cleavage and MMP-1,9,14 induction (p < .05).

Conclusions

Amprenavir, at serum concentrations achievable provided the manufacturer's recommended dose of fosamprenavir for HIV, protects against pepsin-mediated cell dissociation, E-cadherin cleavage, and MMP dysregulation thought to contribute to barrier dysfunction and related symptoms during LPR. Fosamprenavir to amprenavir conversion by laryngeal epithelia, serum and saliva, and relative drug efficacies in an LPR mouse model are under investigation to inform development of inhaled formulations for LPR.

The link between airway reflux and non-acid reflux in children: a review

OBJECTIVE

Airway reflux, a member of extra-esophageal reflux, has been linked to countless respiratory pathologies amongst children. The advent of novel instrumentation has enabled the discovery of non-acid reflux which was postulated as the main culprit of airway reflux. The objective of this review is to outline the association between non-acid reflux and airway reflux in children.

METHODS

A comprehensive review of recent literature on non-acid reflux and airway reflux in children was conducted. Studies ranged from January 2010 till November 2021 were searched over a period of a month: December 2021.

RESULTS

A total of eleven studies were identified. All studies included in this review revealed a strong link between non-acid reflux and airway reflux in children. 6 of the included studies are prospective studies, 3 retrospective studies, 1 cross-section study, and type of study was not mentioned in 1 study. The most common reported respiratory manifestation of non-acid reflux in children was chronic cough (7 studies). Predominant non-acid reflux was noted in 4 studies. The total number of children in each study ranges from 21 to 150 patients. MII-pH study was carried out in all studies included as a diagnostic tool for reflux investigation.

CONCLUSION

Non-acid reflux is the culprit behind airway reflux as well as other myriads of extra-esophageal manifestations in children. Multicentre international studies with a standardized protocol could improve scientific knowledge in managing non-acid reflux in airway reflux amongst children.

Anxiety correlates with excessive air swallowing and PPI refractoriness in patients with concomitant symptoms of GERD and functional dyspepsia

BACKGROUND

Anxiety may exacerbate GERD and FD symptoms perception and reduce quality of life. As many as 50% of patients with GERD symptoms have incomplete relief with PPI therapy, and psychological factors may influence PPI responsiveness.

AIM

The potential relationship between anxiety, excessive air swallowing, and PPI responsiveness was evaluated.

METHODS

GERD patients with concomitant FD were prospectively evaluated. Validated structured questionnaires were used to evaluate anxiety, GERD, and FD symptoms. All patients were treated, within the previous year, with at least 8 weeks of standard dose PPI therapy.

RESULTS

One hundred sixty-one patients were included. Frequency of non-responders in patients with moderate/severe anxiety was significantly higher compared to patients with mild anxiety (62.7% vs. 37.3%, p < 0.01). Patients with moderate/severe anxiety displayed a significantly higher mean FD symptoms score value compared to patients with mild anxiety. A significantly higher mean number of air swallows were observed in patients with moderate/severe anxiety. At ROC analysis, air swallows and mixed reflux episodes were significantly associated with the presence of PPI refractoriness (AUC: 0.725, 95% CI: 0.645-0.805 and 0.768, 0.692-0.843). According to univariate analysis, an abnormal number of air swallows, mixed reflux episodes and presence of moderate/severe anxiety was significantly associated with PPI refractoriness.

CONCLUSION

Our results, if confirmed in in a larger, prospective clinical and therapeutic study, demonstrate the usefulness of an up-front evaluation with anxiety questionnaire and esophageal testing in patients with a broad spectrum of upper gastrointestinal symptoms who fail to respond to PPI treatment, supporting the option of alternative treatment modalities.

Oral and Inhaled Fosamprenavir Reverses Pepsin-Induced Damage in a Laryngopharyngeal Reflux Mouse Model

OBJECTIVE

More than 20% of the US population suffers from laryngopharyngeal reflux. Although dietary/lifestyle modifications and alginates provide benefit to some, there is no gold standard medical therapy. Increasing evidence suggests that pepsin is partly, if not wholly, responsible for damage and inflammation caused by laryngopharyngeal reflux. A treatment specifically targeting pepsin would be amenable to local, inhaled delivery, and could prove effective for endoscopic signs and symptoms associated with nonacid reflux. The aim herein was to identify small molecule inhibitors of pepsin and test their efficacy to prevent pepsin-mediated laryngeal damage in vivo.

METHODS

Drug and pepsin binding and inhibition were screened by high-throughput assays and crystallography. A mouse model of laryngopharyngeal reflux (mechanical laryngeal injury once weekly for 2 weeks and pH 7 solvent/pepsin instillation 3 days/week for 4 weeks) was provided inhibitor by gavage or aerosol (fosamprenavir or darunavir; 5 days/week for 4 weeks; n = 3). Larynges were collected for histopathologic analysis.

RESULTS

HIV protease inhibitors amprenavir, ritonavir, saquinavir, and darunavir bound and inhibited pepsin with IC50 in the low micromolar range. Gavage and aerosol fosamprenavir prevented pepsin-mediated laryngeal damage (i.e., reactive epithelia, increased intraepithelial inflammatory cells, and cell apoptosis). Darunavir gavage elicited mild reactivity and no discernable protection; aerosol protected against apoptosis.

CONCLUSIONS

Fosamprenavir and darunavir, FDA-approved therapies for HIV/AIDS, bind and inhibit pepsin, abrogating pepsin-mediated laryngeal damage in a laryngopharyngeal reflux mouse model. These drugs target a foreign virus, making them ideal to repurpose. Reformulation for local inhaled delivery could further improve outcomes and limit side effects.

LEVEL OF EVIDENCE

NA. Laryngoscope, 133:S1-S11, 2023.

The importance of laryngoscopic findings as predictors of the treatment outcomes of laryngopharyngeal reflux: a retrospective review of 143 cases

Background

Laryngopharyngeal reflux can be described as even a single episode of reflux of gastric acid peptic contents into the larynx and hypopharynx. A large number of new researches show non-acid reflux to be an important cause of LPR symptoms. The present study explores the role of laryngoscopic findings in predicting the treatment outcomes of empirical PPI therapy for LPR.

Methods

A total of 143 patients diagnosed clinically with LPR were evaluated by rigid laryngoscopy and classified into 3 groups based on the Belafsky reflux findings score, as normal (0–7), mild to moderate (8–16), and moderate to severe (17–26).

Results

Twelve out of 39 patients in the normal group, 44 out of 61 patients in the mild to moderate group, and 31 out of 43 patients in the moderate to severe group reported symptomatic improvement after 3 months of PPI therapy and lifestyle modifications. The results were statistically significant.

Conclusion

Pretherapy laryngoscopic findings can be an important predictor of successful treatment outcomes of empirical PPI therapy for LPR.

Relevance of Excessive Air Swallowing in GERD Patients With Concomitant Functional Dyspepsia and Poor Response to PPI Therapy

GOALS

The present study was aimed at evaluating the possible role of air swallowing in the association between gastroesophageal reflux disease (GERD) symptoms and concomitant functional dyspepsia (FD) and their role in GERD symptom persistence despite proton pump inhibitor (PPI) therapy.

BACKGROUND

It has been shown that individuals with excessive air swallowing experience FD. It has been also demonstrated that a consistent group of GERD patients not responding to PPI therapy swallow more air during mealtime and also have more mixed refluxes.

MATERIALS AND METHODS

Multichannel intraluminal impedance-pH tracings from consecutive patients were retrospectively evaluated. A validated structured questionnaire was used to evaluate GERD and concomitant FD symptoms. All patients were treated, within the previous year, with at least 8 weeks of standard-dose PPI therapy.

RESULTS

A total of 35 patients with conclusive GERD, 35 patients with reflux hypersensitivity, and 35 with functional heartburn were studied. A direct relationship was observed between the number of air swallows and of mixed refluxes (R=0.64). At receiver operating characteristic curve analysis, air swallows and mixed refluxes were significantly associated to the presence of FD and PPI refractoriness. An air swallow cutoff of 107 episodes/24 hours was identified to discriminate patients with and without FD (sensitivity: 87%, specificity: 82.8%). A mixed reflux cutoff of 34 episodes/24 hours was identified to discriminate PPI responders from nonresponders (sensitivity: 84.8%, specificity: 69%). At multivariate analysis, an abnormal number of air swallows and of mixed refluxes were significantly associated to FD and PPI refractoriness.

CONCLUSION

Our study highlights the relevant role of excessive air swallowing in eliciting both dyspepsia and refractoriness of typical GERD symptoms to PPI therapy.

Determinants of reflux perception in patients with non-erosive reflux disease who have reflux-related symptoms on potassium-competitive acid blocker therapy

BACKGROUND

This study investigated potential determinants of reflux perception in patients with non-erosive reflux disease (NERD) who had reflux-related symptoms on potassium-competitive acid blocker (P-CAB) therapy.

METHODS

This study included 23 patients with reflux-related symptoms despite P-CAB therapy. Esophageal impedance-pH monitoring was performed on P-CAB and the following potential determinants of reflux perception were investigated: reflux nadir pH value; change in pH (baseline-nadir); bolus clearance time; reflux extent; proportions of acid, weakly acidic, and weakly alkaline reflux episodes; and proportions of liquid and mixed reflux episodes.

RESULTS

Overall, ≥ 90% of all and symptomatic reflux episodes were weakly acidic reflux and 63% of symptomatic reflux episodes were reflux episodes with pH ≥ 5. There were no significant differences regarding potential determinants between symptomatic and asymptomatic reflux episodes. However, the proportion of symptomatic reflux episodes was significantly greater with pH < 5 (13.8%) than with pH ≥ 5 (9.5%) (P = 0.0431). In reflux episodes with pH < 5, the proportion of symptomatic reflux episodes was significantly greater in proximal sites (20.6%) than in distal sites (10.6%) (P = 0.0178). Conversely, in reflux episodes with pH ≥ 5, there was no significant difference regarding reflux perception according to reflux extent (proximal: 9.6% vs. distal: 9.0%, P = 0.9337).

CONCLUSIONS

In patients with P-CAB-resistant NERD, reflux symptoms were mainly caused by reflux episodes with pH ≥ 5 on P-CAB therapy. The proportions of symptomatic reflux episodes among reflux sites differed according to reflux pH value; thus, the mechanisms of reflux perception may differ according to reflux pH value.

An update on current treatment strategies for laryngopharyngeal reflux symptoms

Laryngopharyngeal reflux (LPR) is a syndrome caused by reflux of gastric contents into the pharynx or larynx, which leads to symptoms of throat clearing, hoarseness, pain, globus sensation, cough, excess mucus production in the throat, and dysphonia. LPR is a challenging condition, as there is currently no gold standard for diagnosis or treatment, and thus this presents a burden to the healthcare system. Strategies for treatment of LPR are numerous. Medical therapies include proton pump inhibitors, which are first line, H2 receptor antagonists, alginates, and baclofen. Other noninvasive treatment options include lifestyle therapy and the external upper esophageal sphincter compression device. Endoscopic and surgical options include antireflux surgery, magnetic sphincter augmentation, and transoral incisionless fundoplication. Functional laryngeal disorders and laryngeal hypersensitivity can present as LPR symptoms with or without gastroesophageal reflux disease. Though there are minimal studies in this area, neuromodulators and behavioral interventions are potential treatment options. Given the complexity of these patients and numerous available treatment options, we propose a treatment algorithm to help clinicians diagnose and triage patients into an appropriate therapy.

Antitussive Effect of a Chest Band in Patients with Interstitial Lung Disease: The Preliminary Results from a Pre-post Intervention Study

Objective Evidence supporting the efficiency of clinically administered therapies against interstitial lung disease (ILD)-related cough is limited. Thus, we conducted a study to evaluate the efficacy of short-term use of chest bands on cough in patients with ILD. Methods This pre-post intervention study was performed at two university hospitals between April 2017 and August 2020. Scores of the visual analog scale (VAS) for cough severity (in terms of frequency and intensity), Leicester Cough Questionnaire (LCQ)-acute, and frequency scale for symptoms of gastroesophageal reflux disease (FSSG) were assessed before and after the use of the chest band (24/48 hours). Patients The study included patients with idiopathic interstitial pneumonias (IIPs) or connective tissue disease-associated interstitial lung disease (CTD-ILD). Results Four patients with IIPs and seven with CTD-ILD were included in the analysis. The cough intensity and LCQ-acute total score improved significantly after the use of the chest band (p=0.007 and p=0.005, respectively), although the cough frequency showed no significant reduction (p=0.074). Furthermore, the FSSG total and acid-reflux symptom scores improved (p=0.018 and p=0.027, respectively), and a negative correlation between the change in LCQ-acute total score and that in FSSG score for acid-reflux symptoms was observed (Spearman rho =-0.841, p=0.001). Conclusion The results of the current study suggest that chest bands might be useful for treating chronic refractory cough in patients with ILD and gastroesophageal reflux disease. However, these results should be interpreted with caution due to methodological limitations associated with this study.

Degree of concordance on the management of patients with gastroesophageal reflux disease. A study among specialists that are members of the Sociedad Latinoamericana de Neurogastroenterología (SLNG)

INTRODUCTION AND AIMS

Due to its different clinical manifestations, gastroesophageal reflux disease (GERD) requires diverse diagnostic and therapeutic interventions. The aim of the study was to evaluate the degree of agreement among Latin American specialists, with respect to the management of GERD.

MATERIALS AND METHODS

A cross-sectional study was conducted through a survey with 42 statements (22 related to diagnosis and 20 to treatment) applied to 56 specialists from Latin America. There were 4 possible statement responses: in complete agreement, in partial agreement, in partial disagreement, and in complete disagreement. Reproducibility, level of agreement, and concordance were measured through the Kappa statistic.

RESULTS

The response rate was 81% (47/56). General concordance was low, given that there was complete concordance in only 12 statements (28.6%). There was partial concordance in 22 statements (52.4%) and no concordance in 8 (19%). The following themes had the most disagreement: the performance of endoscopy before beginning treatment, the use of proton pump inhibitors (PPIs) in patients with extraesophageal symptoms and with no typical symptoms, and the combined use of PPIs and prokinetics.

CONCLUSIONS

In the present study, we found that there was agreement among the Latin American specialists for the diagnosis and management of GERD in less than one-third of the recommendations considered standard. The low concordance could be related to the fact that the availability of diagnostic tools and medications, as well as the prevalence of GERD phenotypes, are different in each country.

Impaired Mucosal Integrity in Proximal Esophagus Is Involved in Development of Proton Pump Inhibitor-Refractory Nonerosive Reflux Disease

BACKGROUND AND OBJECTIVE

Weakly acidic reflux reaching to the proximal esophagus is closely related to the perception of gastroesophageal reflux in patients with nonerosive reflux disease despite treatment with a proton pump inhibitor (PPI). However, little is known about the involvement of the patients' mucosal integrity of the proximal esophagus.

METHODS

We recruited 15 symptomatic nonerosive gastroesophageal reflux disease (GERD) patients with a positive symptom index despite PPI treatment and 11 healthy asymptomatic volunteers as controls. The biopsy specimens obtained from the proximal and distal esophagus were applied to a mini-Ussing chamber system to measure transepithelial electrical resistance (TEER) against a pH 4 weak acid. The esophageal biopsy samples were subjected to quantitative real-time PCR and immunohistochemical analysis.

RESULTS

In the proximal esophagus, the weak acid exposure reduced the TEER in the PPI-refractory patients compared to that in the controls. The frequency of the reflux extending to the proximal esophagus had a significant correlation with the reduction in the proximal esophageal TEER in the patients. The reduced TEER in the proximal esophagus was accompanied by an increase in IL-8 and IL-1β mRNA and a decrease in occludin mRNA levels. The proximal esophageal mucosa in the patients presented infiltration of CD3-positive lymphocytes and an increased expression of solute carrier organic anion transporter family member 2A1 (SLCO2A1), a passage gate of reflux symptom-evoking molecules.

CONCLUSIONS

The reflux perception is related to an impairment of the proximal esophageal mucosal integrity in patients with nonerosive reflux disease despite PPI.

Degree of concordance on the management of patients with gastroesophageal reflux disease. A study among specialists that are members of the Sociedad Latinoamericana de Neurogastroenterología (SLNG)

INTRODUCTION AND AIMS

Due to its different clinical manifestations, gastroesophageal reflux disease (GERD) requires diverse diagnostic and therapeutic interventions. The aim of the study was to evaluate the degree of concordance among Latin American specialists, with respect to the management of GERD.

MATERIALS AND METHODS

A cross-sectional study was conducted through a survey with 42 statements (22 related to diagnosis and 20 to treatment) applied to 56 specialists from Latin America. There were 4 possible statement responses: in complete agreement, in partial agreement, in partial disagreement, and in complete disagreement. Reproducibility, level of agreement, and concordance were measured through the Kappa statistic.

RESULTS

The response rate was 81% (47/56). General concordance was low, given that there was complete concordance in only 12 statements (28.6%). There was partial concordance in 22 statements (52.4%) and no concordance in 8 (19%). The following themes had the most disagreement: the performance of endoscopy before beginning treatment, the use of proton pump inhibitors (PPIs) in patients with extraesophageal symptoms and with no typical symptoms, and the combined use of PPIs and prokinetics.

CONCLUSIONS

In the present study, we found that there was agreement among the Latin American specialists for the diagnosis and management of GERD in less than one-third of the recommendations considered standard. The low concordance could be related to the fact that the availability of diagnostic tools and medications, as well as the prevalence of GERD phenotypes, are different in each country.

Association of Pepsin With Inflammatory Signaling and Effusion Viscosity in Pediatric Otitis Media

OBJECTIVE

Otitis media (OM) is a common inflammatory disease spectrum. Cytokine signaling, neutrophil activity, and mucin hypersecretion during recurrent and chronic OM contribute to persistent, viscous middle ear (ME) effusions, hearing loss, and potential for developmental delay. Extraesophageal reflux (EER), specifically pepsin, triggers inflammatory signaling in respiratory mucosa and is associated with OM. The objective of this study was to investigate the association of pepsin with ME inflammatory signaling and the outcomes and examine causality in vitro.

STUDY DESIGN

Cross-sectional study.

METHODS

ME fluid (MEF) and preoperative audiometric data were collected from 30 pediatric subjects undergoing tympanostomy tube placement for recurrent OM or OM with effusion. MEF viscosity was characterized by the surgeon. Pepsin, inflammatory molecules, and mucin were assayed by enzyme-linked immunosorbent assay (ELISA). ME epithelial primary culture was exposed to 0.1 to 1 mg/ml pepsin at pH 5, 6, and 7 for 30 minutes, and cytokine expression was assayed via qPCR.

RESULTS

Pepsin was observed in the MEF of 77% of patients (range 71-2,734 ng/ml). Pepsin correlated with effusion viscosity, interleukins -6 and -8, neutrophil elastase, and mucin 5B (P < .05). Pepsin-negative MEF was more frequently absent of interleukin 8 or mucin 5B (P < .05). Weak acid was generally insufficient to elicit cytokine expression in ME cells in vitro, however, pepsin induced IL6, IL8, and TNF at pH 7 (P < .05) and weak acid (pH 6) facilitated a response at lower pepsin concentration.

CONCLUSIONS

Pepsin may contribute to inflammatory signaling, persistent viscous effusion, and poorer OM outcomes.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Measurement of low-grade inflammation of the esophageal mucosa with electrical conductivity shows promise in assessing PPI responsiveness in patients with GERD

A device that can easily measure electrical impedance might be a helpful tool for investigating the pathophysiology of gastroesophageal reflux disease. The first aim of this study was to validate our newly developed bioelectrical admittance measurement (BAM) through in vitro experimentation. The second aim was to investigate whether evaluation of BAM by this measurement differed between patients with heartburn according to their response to proton pump inhibitor (PPI) therapy. Caco-2 cell monolayers and three-dimensional tissues were examined by BAM using a frequency response analyzer. BAM was also used to measure the impedance through cell layers. Subsequently, BAM was performed during endoscopy in 41 patients experiencing heartburn without esophageal mucosal breaks. After 2-wk administration of 20-mg rabeprazole twice daily, patient responses to PPI were classified as "good" or "poor" according to their clinical course. In each patient, histological alterations and gene expression levels of inflammation mediators and tight junction proteins were evaluated. Impedance profiles indicated that monolayer Caco-2 cells on top of eight-layered normal human dermal fibroblasts had the highest magnitude of impedance over the range of frequencies. In vivo results revealed that patients with good responses to PPI displayed significantly higher admittance. Severity of low-grade inflammation was significantly associated with esophageal wall admittance. Moreover, esophageal wall admittance may be more closely related to basal zone hyperplasia than dilatation of intercellular spaces. Thus, BAM may be able to detect abnormalities in the subepithelial layer of the esophagus.NEW & NOTEWORTHY Bioelectrical admittance measurement is a new method to evaluate esophageal mucosal permeability vertically during upper gastrointestinal endoscopy. Measurement of low-grade inflammation of the esophageal mucosa with electrical conductivity shows promise in assessing proton pump inhibitor responsiveness in patients with gastroesophageal reflux disease. As various gastrointestinal diseases are associated with changes in mucosal permeability, bioelectrical admittance measurement is expected to be clinically applied to therapeutic decision-making for these diseases in the future.

Pepsin Promotes Activation of Epidermal Growth Factor Receptor and Downstream Oncogenic Pathways, at Slightly Acidic and Neutral pH, in Exposed Hypopharyngeal Cells

Pepsin refluxate is considered a risk factor for laryngopharyngeal carcinogenesis. Non-acidic pepsin was previously linked to an inflammatory and tumorigenic effect on laryngopharyngeal cells in vitro. Yet there is no clear evidence of the pepsin-effect on a specific oncogenic pathway and the importance of pH in this process. We hypothesized that less acidic pepsin triggers the activation of a specific oncogenic factor and related-signalling pathway. To explore the pepsin-effect in vitro, we performed intermittent exposure of 15 min, once per day, for a 5-day period, of human hypopharyngeal primary cells (HCs) to pepsin (1 mg/mL), at a weakly acidic pH of 5.0, a slightly acidic pH of 6.0, and a neutral pH of 7.0. We have documented that the extracellular environment at pH 6.0, and particularly pH 7.0, vs. pH 5.0, promotes the pepsin-effect on HCs, causing increased internalized pepsin and cell viability, a pronounced activation of EGFR accompanied by NF-κB and STAT3 activation, and a significant upregulation of EGFR, AKT1, mTOR, IL1β, TNF-α, RELA(p65), BCL-2, IL6 and STAT3. We herein provide new evidence of the pepsin-effect on oncogenic EGFR activation and its related-signaling pathway at neutral and slightly acidic pH in HCs, opening a window to further explore the prevention and therapeutic approach of laryngopharyngeal reflux disease.

ESNM/ANMS consensus paper: Diagnosis and management of refractory gastro-esophageal reflux disease

Up to 40% of patients with symptoms suspicious of gastroesophageal reflux disease (GERD) do not respond completely to proton pump inhibitor (PPI) therapy. The term "refractory GERD" has been used loosely in the literature. A distinction should be made between refractory symptoms (ie, symptoms may or may not be GERD-related), refractory GERD symptoms (ie, persisting symptoms in patients with proven GERD, regardless of relationship to ongoing reflux), and refractory GERD (ie, objective evidence of GERD despite adequate medical management). The present ESNM/ANMS consensus paper proposes use the term "refractory GERD symptoms" only in patients with persisting symptoms and previously proven GERD by either endoscopy or esophageal pH monitoring. Even in this context, symptoms may or may not be reflux related. Objective evaluation, including endoscopy and esophageal physiologic testing, is requisite to provide insights into mechanisms of symptom generation and evidence of true refractory GERD. Some patients may have true ongoing refractory acid or weakly acidic reflux despite PPIs, while others have no evidence of ongoing reflux, and yet others have functional esophageal disorders (overlapping with proven GERD confirmed off therapy). In this context, attention should also be paid to supragastric belching and rumination syndrome, which may be important contributors to refractory symptoms.

Survival after antireflux surgery versus medication in patients with reflux oesophagitis or Barrett's oesophagus: multinational cohort study

BACKGROUND

The aim was to examine the hypothesis that antireflux surgery with fundoplication improves long-term survival compared with antireflux medication in patients with reflux oesophagitis or Barrett's oesophagus.

METHOD

Individuals aged between 18 and 70 years with reflux oesophagitis or Barrett's oesophagus (intestinal metaplasia) documented from in-hospital and specialized outpatient care were selected from national patient registries in Denmark, Finland, Iceland, and Sweden from 1980 to 2014. The study investigated all-cause mortality and disease-specific mortality, comparing patients who had undergone open or laparoscopic antireflux surgery with fundoplication versus those using antireflux medication. Multivariable Cox regression analysis was used to estimate hazard ratios (HRs) with 95 per cent confidence intervals for all-cause mortality and disease-specific mortality, adjusted for sex, age, calendar period, country, and co-morbidity.

RESULTS

Some 240 226 patients with reflux oesophagitis or Barrett's oesophagus were included, of whom 33 904 (14.1 per cent) underwent antireflux surgery. The risk of all-cause mortality was lower after antireflux surgery than with use of medication (HR 0.61, 95 per cent c.i. 0.58 to 0.63), and lower after laparoscopic (HR 0.56, 0.52 to 0.60) than open (HR 0.80, 0.70 to 0.91) surgery. After antireflux surgery, mortality was decreased from cardiovascular disease (HR 0.58, 0.55 to 0.61), respiratory disease (HR 0.62, 0.57 to 0.66), laryngeal or pharyngeal cancer (HR 0.35, 0.19 to 0.65), and lung cancer (HR 0.67, 0.58 to 0.80), but not from oesophageal cancer (HR 1.05, 0.87 to 1.28), compared with medication, The decreased mortality rates generally remained over time.

CONCLUSION

In patients with reflux oesophagitis or Barrett's oesophagus, antireflux surgery is associated with lower mortality from all causes, cardiovascular disease, respiratory disease, laryngeal or pharyngeal cancer, and lung cancer, but not from oesophageal cancer, compared with antireflux medication.

The role of serotonin in the control of esophageal sensitivity assessed by multimodal stimulation in health

BACKGROUND

Esophageal hypersensitivity is considered an important pathophysiological mechanism in refractory gastroesophageal reflux disease (GERD) patients. Serotonin (5-HT) plays an important role in the regulation of GI (gastrointestinal) secretion, motility and sensitivity. Previous studies found that altered 5-HT availability has no clear effects on esophageal/GI sensations. Our aim was therefore to investigate the role of 5-HT in esophageal sensitivity in healthy volunteers (HV).

METHODS

Esophageal sensitivity to thermal, mechanical, electrical, and chemical stimuli was assessed in 3 different placebo-controlled studies. In the first study, the effect of citalopram (40 mg; 5-HT reuptake inhibitor; intravenous) was investigated (n = 14). In the second study, the effect of buspirone (20 mg; 5HT1A agonist; oral) was investigated (n = 10). In the third study, acute tryptophan depletion (ATD) was used to decrease 5-HT levels to investigate the effect of reduced 5-HT availability on esophageal sensitivity (n = 15).

KEY RESULTS

No difference was observed in esophageal sensitivity after the administration of citalopram or buspirone (all p > 0.06). In contrast, pain perception threshold to chemical stimulation was increased after ATD (p = 0.017, Cohen's d+ = 0.67). No effect was found on the first perception or pain tolerance threshold. ATD had no influence on esophageal sensitivity to thermal, mechanical, and electrical stimulation compared with placebo.

CONCLUSIONS AND INFERENCES

ATD, which induces 5-HT depletion, significantly decreased pain perception threshold during chemical stimulation, without affecting sensitivity to mechanical, thermal, or electrical stimulation. These findings confirm the involvement of 5-HT in the control of esophageal acid sensitivity, but identifying the receptors involved requires more ligands and studies.

Assessment of the Multiple Rapid Swallows Test for Gauging Esophageal Reflux Burden in Patients with Refractory Gastroesophageal Reflux Disease

BACKGROUND The multiple rapid swallows (MRS) test is used to assess esophageal contraction reserve. In this study, we characterized the expression of the MRS test in patients with reflux burden and other symptomatic phenotypes with refractory gastroesophageal reflux disease (rGERD). MATERIAL AND METHODS Patients with rGERD who underwent high-resolution manometry (HRM) and esophageal pH-impedance monitoring (EIM) between September 2018 and January 2020 were retrospectively studied. RESULTS We enrolled 151 patients and divided them into 4 phenotypes according to the results of EIM. In phenotype 1, the MRS distal contractile integral (DCI) was significantly positively correlated with acid-liquid reflux episodes. In phenotype 2, lower esophageal sphincter pressure (LES) length was significantly positively correlated with MRS DCI, and MRS/single-swallow (SS) DCI ratio. In phenotype 3, MRS DCI was negatively correlated with the DeMeester score, acid exposure time (AET), upright AET, long-term acid reflux episodes, acid-mixed reflux episodes, recumbent acid reflux episodes, and total acid reflux episodes. There was a significant negative correlation between MRS/SS DCI and recumbent acid reflux episodes. In phenotype 4, nonacid-liquid episodes and recumbent nonacid reflux episodes were significantly higher in the abnormal MRS group. However, acid-gas episodes, weakly acid-gas episodes, and upright gas reflux episodes were higher in the normal MRS group than in the abnormal MRS group. CONCLUSIONS Esophageal contraction reserve is heterogeneous within the reflux burden and symptomatic phenotypes of patients with rGERD.

Antireflux surgery and risk of lung cancer by histological type in a multinational cohort study

INTRODUCTION

Airway micro-aspiration might contribute to the proposed associations between gastroesophageal reflux disease (GERD) and some lung diseases, including lung cancer. This study aimed to examine the hypothesis that antireflux surgery decreases the risk of small cell carcinoma, squamous cell carcinoma and adenocarcinoma of the lung differently depending on their location in relation to micro-aspiration.

METHODS

Population-based cohort study including patients having undergone antireflux surgery during 1980-2014 in Denmark, Finland, Iceland, Norway or Sweden. Patients having undergone antireflux surgery were compared with two groups: 1) the corresponding background population, by calculating standardised incidence ratios (SIRs) with 95% confidence intervals (CIs) and 2) non-operated GERD-patients, by calculating hazard ratios (HRs) with 95% CIs using multivariable Cox regression with adjustment for sex, age, calendar period, country, chronic obstructive pulmonary disease and obesity diagnosis or type 2 diabetes.

RESULTS

Among all 812,617 GERD-patients, 46,996 (5.8%) had undergone antireflux surgery. The SIRs were statistically significantly decreased for small cell carcinoma (SIR = 0.57, 95% CI 0.41-0.77) and squamous cell carcinoma (SIR = 0.75, 95% CI 0.60-0.92), but not for adenocarcinoma of the lung (SIR = 0.90, 95% CI 0.76-1.06). The HRs were also below unity for small cell carcinoma (HR = 0.63, 95% CI 0.44-0.90) and squamous cell carcinoma (HR = 0.80, 95% CI 0.62-1.03), but not for adenocarcinoma of the lung (HR = 1.03, 95% CI 0.84-1.26). Analyses restricted to patients with objective GERD (reflux oesophagitis or Barrett's oesophagus) showed similar results.

CONCLUSIONS

This all-Nordic study indicates that patients who undergo antireflux surgery are at decreased risk of small cell carcinoma and squamous cell carcinoma of the lung, but not of adenocarcinoma of the lung.

Pepsin and Laryngeal and Hypopharyngeal Carcinomas

Laryngeal and hypopharyngeal carcinomas are common malignant tumors of the head and neck, and the incidence of both is increasing. Laryngopharyngeal reflux refers to the retrograde flow of gastric contents into the larynx, oropharynx, and/or nasopharynx. It remains controversial whether laryngopharyngeal reflux is a risk factor for laryngeal and hypopharyngeal cancers. The refluxing substances mainly include hydrochloric acid, pepsin, and occasionally bile acids and bile salts, as well as bacteria that colonize the gastrointestinal tract. Loss of epithelium in the mucous membrane of the larynx and hypopharynx is thought to be caused by pepsin. Here, we review the relationships between laryngopharyngeal reflux and both laryngeal and hypopharyngeal carcinomas, as well as the significance of pepsin, methods of clinical detection, and the mechanism of carcinogenesis.

RNA Sequencing Reveals Cancer-Associated Changes in Laryngeal Cells Exposed to Non-Acid Pepsin

OBJECTIVE

Laryngopharyngeal reflux (LPR) is a common affliction that contributes to laryngeal inflammation, symptoms that impact quality of life, and life-threatening illnesses such as cancer. Effective treatment strategies for LPR are lacking. Pepsin is a proinflammatory and carcinogenic element of refluxate. Investigation of molecular pathways involved in pepsin-mediated damage may lead to identification of novel biomarkers and therapeutic targets for LPR. In this study, RNA sequencing was used to examine changes in human laryngeal epithelial cells following brief pepsin insult. Cells were immortalized to generate a model to aid future study of laryngeal injury and therapeutics.

STUDY DESIGN

In vitro translational.

METHODS

Laryngeal epithelial cells were cultured from a patient without signs or symptoms of LPR or laryngeal cancer. Cells were treated with 0.1 mg/ml pepsin for 1 hour or normal growth media (control) prior to RNA sequencing. Cells were immortalized via HPV E6/7 and characterized by microscopy, immunohistochemistry, G-banding, and soft agar assay.

RESULTS

Three hundred ninety-seven genes exhibited differences in expression with pepsin treatment (P < .05). Pathway analysis revealed association with cancer and related signaling processes including dysregulation of cancer-associated molecules, Metastasis-Associated Lung Adenocarcinoma Transcript 1 and KRT82, and the long-noncoding RNA, lipoprotein receptor-related protein 1 (LRP1)-AS, which regulates the putative pepsin receptor LRP1.

CONCLUSIONS

A single, brief exposure to pepsin activated cancer-associated signaling pathways in laryngeal cells in vitro, revealing novel mechanisms by which chronic reflux may contribute to carcinogenesis. The cell line developed herein represents a novel tool in which to investigate pepsin-dysregulated pathways identified by RNA sequencing and disparities of tumor proneness of laryngeal subsites.

LEVEL OF EVIDENCE

N/A Laryngoscope, 131:121-129, 2021.

New classifications of gastroesophageal reflux disease: an improvement for patient management?

Introduction: Gastroesophageal reflux disease (GERD) is a very common and often debilitating disease. In the broad spectrum of GERD phenotypes, three main groups may be traditionally distinguished: 1) patients only affected by esophageal and/or extra-esophageal symptoms; 2) patients with erosive esophagitis and 3) patients with further complications. Areas covered: This review provides an overview on the current classifications of GERD patients, and their impact on their management. Expert opinion: In 2017, the GERD Consensus Working Group focused the attention on patients unresponsive to PPIs. In this scenario, a diagnosis of GERD might be confirmed by evident signs of erosive esophagitis and the finding of pH or multichannel intraluminal impedance-pH tests, such as more than 6%. The 'Lyon Consensus' panel of experts confirmed that positive indices of reflux-symptom association, without other altered parameters, represent reflux hypersensitivity. GERD requires a customized management; it is crucial to assess frequency and severity of symptoms and their response to an optimal course of therapy as well as to explore the endoscopic alterations and consider other diagnoses responsible for persistent symptoms.

Most Patients With Gastroesophageal Reflux Disease Who Failed Proton Pump Inhibitor Therapy Also Have Functional Esophageal Disorders

BACKGROUND & AIMS

As many as 45% of patients with gastroesophageal reflux disease (GERD) still have symptoms after receiving once-daily proton pump inhibitor (PPI) therapy. We aimed to compare reflux characteristics and patterns between responders and non-responders to once-daily PPI therapy using combined impedance-pH monitoring.

METHODS

Patients who reported heartburn and/or regurgitation at least twice per week for 3 months while receiving standard-dose PPI therapy were assigned to the PPI failure group (n = 16). Patients who reported a complete resolution of symptoms on once-daily PPIs for at least 4 weeks were assigned to the PPI success group (n = 13). We collected demographic data and subjects completed the short-form 36 and the GERD health-related quality of life questionnaires. Patients then underwent upper endoscopy and combined esophageal impedance-pH monitoring while on PPI therapy.

RESULTS

Four patients in the PPI success group (31%) and 4 patients in the PPI failure group (25%) had abnormal results from the pH test (P = 1.00). Most of the patients in the PPI failure group (75%) were found to have either functional heartburn or reflux hypersensitivity with GERD. Impedance and pH parameters did not differ significantly between the PPI failure and success group.

CONCLUSIONS

We found no difference in reflux characteristics between patients with GERD who had successful vs failed once-daily PPI therapy. Most patients in the PPI failure group (75%) had functional esophageal disorders.

Diagnostic yield of ambulatory oesophageal studies on versus off proton pump inhibitors: a systematic review and meta-analysis

BACKGROUND

Patients with persistent gastroesophageal reflux disease symptoms despite proton pump inhibitors are increasingly encountered. It remains controversial if proton pump inhibitors should be stopped before functional oesophageal tests.

AIM

This meta-analysis compares the positive yield of oesophageal studies performed off versus on proton pump inhibitors.

METHODS

Pubmed, Embase and the Cochrane Library were searched for eligible studies. Outcomes assessed were the number of subjects with: elevated oesophageal acid exposure time when studied off versus on proton pump inhibitors; positive symptom index (≥50%) and/or positive symptom association probability (≥95%) for acid reflux; and/or non-acid reflux events off versus on proton pump inhibitors. The random effects model was applied.

RESULTS

Fifteen studies (n = 5033 individuals; 33% on proton pump inhibitors; 32% men; mean age 52.1 years) were analysed. Pooled risk ratio for the comparison of high oesophageal acid exposure time off versus on proton pump inhibitors was 2.16 (95% confidence interval (CI) 1.42-3.28). The risk ratio of a positive symptom index (acid reflux) was 2.64 (95% CI 1.52-4.57) and the risk ratio of a positive symptom association probability (acid reflux) was 2.94 (95% CI 2.31-3.74). Conversely, the risk ratio of a positive symptom index (non-acid reflux) was 0.96 (95% CI 0.49-1.88) and risk ratio of a positive symptom association probability (non-acid reflux) was 0.54 (95% CI 0.30-0.99).

CONCLUSIONS

Oesophageal studies after proton pump inhibitor cessation improve the positive yield for acid reflux-related events but reduce the detection of symptomatic non-acid reflux events.

Prevalence and clinical characteristics of refractoriness to optimal proton pump inhibitor therapy in non-erosive reflux disease

BACKGROUND

The real size of the gastro-oesophageal reflux disease (GERD) population not responding to proton pump inhibitor (PPI) therapy has still not been fully elucidated. Causes of PPI refractoriness include incorrect diagnosis and lack of adherence to therapy, in terms of incorrect dosage and timing.

AIMS

To evaluate the prevalence of refractoriness to optimal PPI therapy and the contribution of non-erosive reflux disease (NERD), reflux hypersensitivity, and functional heartburn, to PPI refractoriness. The association of functional GI symptoms in non-responders was evaluated.

METHODS

Frequency and severity of GERD symptoms (heartburn, regurgitation, chest pain), dysphagia, belching, epigastric pain, postprandial distress, irritable bowel syndrome (IBS), globus, and ear nose and throat (ENT) symptoms were evaluated in patients previously classified as non-responders. Patients with at least one of the oesophageal symptoms with a frequency ≥3 /week were treated with esomeprazole 40 mg once daily for 8 weeks and then re-evaluated. Non-responders (patients with oesophageal symptoms ≥3 times per week) underwent 24 hour multichannel intraluminal impedance-pH monitoring.

RESULTS

Of 573 consecutive patients, 92 with oesophageal symptoms and classified as PPI-refractory underwent the esomeprazole trial; 60 did not respond. IBS, epigastric pain, and post-prandial distress episodes were associated with a poor response on multivariate analysis. NERD, reflux hypersensitivity, and functional heartburn patients constituted 32%, 42%, and 26%, respectively of the PPI-refractory group.

CONCLUSIONS

True refractoriness in patients with GERD symptoms attending a secondary care setting is lower than previously reported. Following a careful history and optimal PPI dosing, the rate of refractoriness was 20%. True NERD constitutes only a third of the PPI-refractory group.

A reduced esophageal epithelial integrity in a subgroup of healthy individuals increases with proton pump inhibitor therapy

INTRODUCTION

Approximately 30% of healthy volunteers (HVs) show dilated intercellular spaces in the esophageal epithelium suggesting a functionally reduced epithelial integrity. We aimed to evaluate the presence of an altered epithelial integrity in HVs and whether physiological acid could explain such a difference.

METHODS

Biopsies for Ussing chamber experiments were taken between 3 cm and 5 cm proximal to the gastroesophageal junction. Twenty-four-hour impedance-pH (MII-pH) monitoring was performed in the same 15 HVs. MII-pH tracings from 24 HVs before and after treatment with esomeprazole (40 mg b.i.d., two weeks), a proton pump inhibitor, were analyzed. Reflux parameters and impedance baseline (IB) at different levels of the esophagus were calculated.

RESULTS

Epithelial integrity in the distal esophagus presents a large variability in vivo and in vitro (transepithelial electrical resistance 196.9 ± 16.27Ω. cm2; IB measurements 2022 ± 143.5Ω). Esomeprazole highly suppressed the total acid exposure time (AET) (1.9 (0.8-3.1) vs 0 (0-0)%, p < 0.0001). After splitting our participants into "high" and "low" IB, based on the median value, we observed only in the distal esophagus a higher total AET before (2.8 (1.6-4.8) vs 1.0 (0.5-2.2), p = 0.04) and increased IB values after esomeprazole (1620 (1347-1898) vs 2192 (1784-2503)Ω, p = 0.002) in the "low" IB group.

CONCLUSION

A subgroup of HVs presents a low epithelial integrity in the distal esophagus probably due to the increased presence of physiological acid reflux. Whether these individuals have a higher chance to develop gastroesophageal reflux disease is unknown. The role of epithelial integrity in symptom perception needs to be further explored.

Increased Esophageal Exposure to Weakly Acidic Reflux 5 Years After Laparoscopic Roux-en-Y Gastric Bypass

OBJECTIVE

To evaluate the long-term effects of laparoscopic Roux-en-Y Gastric Bypass (LRYGB) on gastroesophageal function.

BACKGROUND

LRYGB is considered the weight loss procedure of choice for obese patients with gastroesophageal reflux disease (GERD). However, long-term instrumental evaluations of GERD after LRYGB are not available.

METHODS

Morbidly obese patients selected for LRYGB were included in a prospective study. We performed clinical evaluation with GERD-HRQoL questionnaire, upper endoscopy, esophageal manometry, and 24-hour impedance pH (24-hour MII-pH) monitoring preoperatively and at 12 and 60 months after surgery. This trial is registered with ClinicalTrials.gov (no. NCT02618044).

RESULTS

From May 2006 to May 2009, 86 patients entered the study and 72 (84%) completed the 5-year protocol. At preoperative 24-hour MII-pH monitoring, 54 patients (group A) had normal values, whereas 32 (group B) had diagnosis of GERD: 23 had acidic reflux, whereas 9 had combined reflux [acidic + weakly acidic reflux (WAR)]. The groups were similar in preoperative age, body mass index, and comorbidities. At 12 and 60 months, significant improvement in questionnaire scores was observed in group B patients. No manometric changes occurred in both groups; 24-hour MII-pH monitoring showed a significant reduction in acid exposure, but an increase of WAR in both group A (from 0% to 52% to 74%) and group B (from 35% to 42% to 77%). At long-term follow-up, esophagitis was found in 14 group A (30%) and in 18 group B patients (69%) (P < 0.001).

CONCLUSIONS

LRYGB allows to obtain an effective GERD symptom amelioration and a reduction in acid exposure. However, 3 out 4 patients present with distal esophagus exposure to WAR.

The effect of intravenous corticotropin-releasing hormone administration on esophageal sensitivity and motility in health

Esophageal hypersensitivity is important in gastroesophageal reflux disease (GERD) patients who are refractory to acid-suppressive therapy. Stress affects visceral sensitivity and exacerbates heartburn in GERD. Peripheral CRH is a key mediator of the gut stress response. We hypothesize that CRH increases esophageal sensitivity and alters esophageal motility in health. Esophageal sensitivity to thermal, mechanical, electrical, and chemical stimuli was assessed in 14 healthy subjects after administration of placebo or CRH (100 μg iv). Perception scores were assessed for first perception, pain perception threshold (PPT), and pain tolerance threshold (PTT). Esophageal motility was investigated by high-resolution impedance manometry, before and after CRH and evaluated by distal contractile integral (DCI) and intrabolus pressure (IBP). Pressure flow analysis assessed bolus clearance (impedance ratio), degree of pressurization needed to propel bolus onward (IBP slope), and pressure flow (pressure flow index, PFI). Stress and mood were assessed during the study. Sensitivity to mechanical distention was increased after CRH compared with placebo (PPT: P = 0.0023; PTT: P = 0.0253). CRH had no influence on the other stimulations. DCI was increased for all boluses (liquid, P = 0.0012; semisolid, P = 0.0017; solid, P = 0.0107). Impedance ratio for liquid (P < 0.0001) and semisolid swallows (P = 0.0327) decreased after CRH. IBP slope increased after CRH for semisolid (P = 0.0041) and solid (P = 0.0003) swallows. PFI increased for semisolid (P = 0.0017) and solid swallows (P = 0.0031). CRH increased esophageal sensitivity to mechanical distention, not to the other stimulation modalities. CRH increased esophageal contractility and tone, decreased LES relaxation, increased esophageal bolus pressurization, improved esophageal bolus clearance, and increased pressure flow.NEW & NOTEWORTHY This is the first study to address the effect of corticotropin-releasing hormone (CRH) on esophageal sensitivity and alterations in motility in health. CRH administration increased esophageal sensitivity to mechanical distention. This effect is accompanied by an increase in esophageal contractility and tone and a decrease in lower esophageal sphincter relaxation. CRH increased esophageal bolus pressurization, improved esophageal bolus clearance, and increased pressure flow. The changes in esophageal contractile properties may underlie the increased sensitivity to mechanical distention after CRH.

Novel insights into esophageal diagnostic procedures

The 21st century offers new advances in diagnostic procedures and protocols in the management of esophageal diseases. This review highlights the most recent advances in esophageal diagnostic technologies, including clinical applications of novel endoscopic devices, such as ultrathin endoscopy and confocal laser endomicroscopy for diagnosis and management of Barrett's esophagus; novel parameters and protocols in high-resolution esophageal manometry for the identification and better classification of motility abnormalities; innovative connections between esophageal motility disorder diagnosis and detection of gastroesophageal reflux disease (GERD); impedance-pH testing for detecting the various GERD phenotypes; performance of distensibility testing for better pathophysiological knowledge of the esophagus and other gastrointestinal abnormalities; and a modern view of positron emission tomography scanning in metastatic disease detection in the era of accountability as a model for examining other new technologies. We now have better tools than ever for the detection of esophageal diseases and disorders, and emerging data are helping to define how well these tools change management and provide value to clinicians. This review features novel insights from multidisciplinary perspectives, including both surgical and medical perspectives, into these new tools, and it offers guidance on the use of novel technologies in clinical practice and future directions for research.

Prevention of DNA damage in Barrett's esophageal cells exposed to acidic bile salts

Esophageal adenocarcinoma (EA) is one of the fastest rising tumors in the USA. The major risk factor for EA is gastroesophageal reflux disease (GERD). During GERD, esophageal cells are exposed to refluxate which contains gastric acid frequently mixed with duodenal bile. This may lead to mucosal injury and Barrett's metaplasia (BE) that are important factors contributing to development of EA. In this study, we investigated DNA damage in BE cells exposed to acidic bile salts and explored for potential protective strategies. Exposure of BE cells to acidic bile salts led to significant DNA damage, which in turn, was due to generation of reactive oxygen species (ROS). We found that acidic bile salts induce a rapid increase in superoxide radicals and hydrogen peroxide, which were determined using electron paramagnetic resonance spectroscopy and Amplex Red assay. Analyzing a panel of natural antioxidants, we identified apocynin to be the most effective in protecting esophageal cells from DNA damage induced by acidic bile salts. Mechanistic analyses showed that apocynin inhibited ROS generation and increases the DNA repair capacity of BE cells. We identified BRCA1 and p73 proteins as apocynin targets. Downregulation of p73 inhibited the protective effect of apocynin. Taken together, our results suggest potential application of natural compounds such as apocynin for prevention of reflux-induced DNA damage and GERD-associated tumorigenesis.

Mucosal integrity and sensitivity to acid in the proximal esophagus in patients with gastroesophageal reflux disease

Acid reflux episodes that extend to the proximal esophagus are more likely to be perceived. This suggests that the proximal esophagus is more sensitive to acid than the distal esophagus, which could be caused by impaired mucosal integrity in the proximal esophagus. Our aim was to explore sensitivity to acid and mucosal integrity in different segments of the esophagus. We used a prospective observational study, including 12 patients with gastroesophageal reflux disease (GERD). After stopping acid secretion-inhibiting medication, two procedures were performed: an acid perfusion test and an upper endoscopy with electrical tissue impedance spectroscopy and esophageal biopsies. Proximal and distal sensitivity to acid and tissue impedance were measured in vivo, and mucosal permeability and epithelial intercellular spaces at different esophageal levels were measured in vitro. Mean lag time to heartburn perception was much shorter after proximal acid perfusion (0.8 min) than after distal acid perfusion (3.9 min) (P = 0.02). Median in vivo tissue impedance was significantly lower in the distal esophagus (4,563 Ω·m) compared with the proximal esophagus (8,170 Ω·m) (P = 0.002). Transepithelial permeability, as measured by the median fluorescein flux was significantly higher in the distal (2,051 nmol·cm(-2)·h(-1)) than in the proximal segment (368 nmol·cm(-2)·h(-1)) (P = 0.033). Intercellular space ratio and maximum heartburn intensity were not significantly different between the proximal and distal esophagus. In GERD patients off acid secretion-inhibiting medication, acid exposure in the proximal segment of the esophagus provokes symptoms earlier than acid exposure in the distal esophagus, whereas mucosal integrity is impaired more in the distal esophagus. These findings indicate that the enhanced sensitivity to proximal reflux episodes is not explained by increased mucosal permeability.

Airway reflux

An ever-increasing number of adult and pediatric disorders have been shown to be influenced or caused by airway reflux. This has become a controversial and complicated aspect of medicine that requires a multidisciplinary approach. Evidence indicates that it is not only the acidic components of gastric refluxate that injure extraesophageal tissues but also the nonacidic components, such as pepsin and bile. There is a realization that proton pump inhibitors will not be effective when nonacidic components of refluxate are causing the problem. New in vitro and in vivo models for the study of airway reflux and new therapeutic and surgical approaches are discussed in this review article.

Management of refractory typical GERD symptoms

The management of patients with refractory GERD (rGERD) is a major clinical challenge for gastroenterologists. In up to 30% of patients with typical GERD symptoms (heartburn and/or regurgitation), acid-suppressive therapy does not provide clinical benefit. In this Review, we discuss the current management algorithm for GERD and the features and management of patients who do not respond to treatment (such as those individuals with an incorrect diagnosis of GERD, inadequate PPI intake, persisting acid reflux and persisting weakly acidic reflux). Symptom response to existing surgical techniques, novel antireflux procedures, and the value of add-on medical therapies (including prokinetics and reflux inhibitors) for rGERD symptoms are discussed. Pharmaceutical agents targeting oesophageal sensitivity, a condition that can contribute to symptom generation in rGERD, are also discussed. Finally, on the basis of available published data and our expert opinion, we present an outline of a current, usable algorithm for management of patients with rGERD that considers the timing and diagnostic use of pH-impedance monitoring on or off PPI, additional diagnostic tests, the clinical use of baclofen and the use of add-on neuromodulators (tricyclic agents and selective serotonin reuptake inhibitors).

Characteristics of symptomatic reflux episodes in Japanese proton pump inhibitor-refractory non-erosive reflux disease patients

AIM: To clarify the pathogenesis of gastroesophageal reflux disease symptoms in non-erosive reflux disease (NERD) patients.

METHODS: Thirty-five NERD patients with persistent symptoms, despite taking rabeprazole 10 mg twice daily for at least 8 wk, were included in this study. All patients underwent 24 h combined impedance - pH on rabeprazole. The symptom index (SI) was considered to be positive if ≥ 50%, and proximal reflux episodes were determined when reflux reached 15 cm above the proximal margin of the lower esophageal sphincter.

RESULTS: In 14 (40%) SI-positive patients, with liquid weakly acid reflux, the occurrence rate of reflux symptoms was significantly more frequent in proximal reflux episodes (46.7%) than in distal ones (5.7%) (P < 0.001). With liquid acid reflux, there were no significant differences in the occurrence rate of reflux symptoms between proximal reflux episodes (38.5%) and distal ones (20.5%) (NS). With mixed liquid-gas weakly acid reflux, the occurrence rate of reflux symptoms in proximal reflux episodes was significantly more frequent (31.0%) than in distal reflux ones (3.3%) (P < 0.001). With mixed liquid-gas acid reflux, there were no significant differences in the occurrence rate of reflux symptoms between proximal reflux episodes (29.4%) and distal ones (14.3%) (NS).

CONCLUSION: The proximal extent of weakly acidic liquid and mixed liquid-gas reflux is a major factor associated with reflux perception in SI-positive patients on proton pump inhibitor therapy.

Majority of symptoms in esophageal reflux PPI non-responders are not related to reflux

BACKGROUND

Genesis of persistent gastro-esophageal reflux symptoms despite proton pump inhibitor (PPI) therapy is not fully understood. We aimed at determining reflux patterns on 24-h pH-impedance monitoring performed on PPI and correlating impedance patterns and symptom occurrence in PPI non-responders.

METHODS

Seventy-eight PPI non-responder patients underwent 24-h pH-impedance monitoring on PPI. Reflux impedance characterization included gastric and supragastric belches and proximal extent of reflux. Symptoms were considered associated with reflux if occurring within 5 min after a reflux event. Patients were classified into three groups: persistent acid reflux (acid esophageal exposure [AET] >5% of time), reflux sensitivity (AET <5%, symptom index [SI] ≥50%), and functional symptoms (AET <5%, SI <50%). Dominant impedance pattern was determined for each patient.

KEY RESULTS

Seven patients (9%) had persistent acid reflux, 28 (36%) reflux sensitivity, and 43 (55%) functional symptoms. A total of 4296 reflux events were identified (median per patient 45 [range 4-221]). Although liquid reflux was the most common pattern in all groups, patients with reflux sensitivity and functional symptoms had much more variability in their pattern profile with a large proportion being associated with gastric and supragastric belching. Only 417 reflux events (9.7%) were associated with symptoms. Reflux with a supragastric component and proximal extent were more likely to be associated with symptoms.

CONCLUSIONS & INFERENCES

The impedance reflux profile in PPI non-responders was heterogeneous and the majority of reflux events were not associated with symptoms. Thus, the treatment of PPI non-responders should focus on mechanisms beyond reflux, such as visceral hypersensitivity and hypervigilance.

Patients with refractory reflux symptoms often do not have GERD

BACKGROUND

In patients with typical reflux symptoms that persist despite proton pump inhibitors (PPIs) it is sometimes overlooked that treatment fails due to the presence of other disorders than gastroesophageal reflux disease (GERD). The aim of this study was to determine the underlying cause of reflux symptoms not responding to PPI therapy in tertiary referral patients.

METHODS

Patients with reflux symptoms refractory to PPI therapy who underwent 24-h pH-impedance monitoring were analyzed. Patients in whom a diagnosis was already established before referral, who had previous esophageal or gastric surgery, or who had abnormalities on gastroscopy other than hiatus hernia, were excluded.

KEY RESULTS

In total, 106 patients were included. Esophageal manometry showed achalasia in two patients and distal esophageal spasm in another two. Twenty-four-hour pH-impedance monitoring revealed a total acid exposure time <6% in 60 patients (56.6%) of which 25 had a positive symptom association probability (SAP) while 35 showed a negative SAP. Sixty-nine patients ended up with a final diagnosis of GERD while 32 patients (30.2%) were diagnosed with functional heartburn (FH), two with functional chest pain, two with achalasia, and one with rumination. A trend toward an association with a final diagnosis of FH was found with the atypical symptom epigastric pain (p = 0.059) and with a secondary diagnosis of functional dyspepsia (p = 0.083).

CONCLUSIONS & INFERENCES

Approximately one-third of the patients referred with refractory reflux symptoms suffer from disorders other than GERD, predominantly FH. This explains, at least partly, why many patients will not benefit from acid inhibitory treatment.

Randomised clinical trial: the 5-HT4 agonist revexepride in patients with gastro-oesophageal reflux disease who have persistent symptoms despite PPI therapy

BACKGROUND

A substantial proportion of patients with gastro-oesophageal reflux disease (GERD) have only a partial response to proton pump inhibitor (PPI) therapy. Prokinetic drugs may improve reflux symptoms by enhancing oesophageal motility and gastric emptying.

AIM

To evaluate the effect of revexepride, a novel prokinetic 5-hydroxytryptamine type 4 (5-HT4 ) receptor agonist, compared with placebo, in patients with GERD who have a partial response to PPIs.

METHODS

A phase 2b, double-blind, parallel-group study was conducted, in which patients were randomised to one of three revexepride treatment groups (0.1, 0.5 and 2.0 mg three times daily) or placebo (1:1:1:1 ratio). Daily e-diary data captured patients' symptoms over an 8-week treatment period. The primary efficacy outcome was the weekly percentage of regurgitation-free days in the second half of the study (weeks 5-8).

RESULTS

In total, 480 patients were randomised and 477 received treatment (mean age 47.9 years; 61% women). The mean percentage of regurgitation-free days increased from baseline (range, 15.0-18.8%) to week 8 (62.3-70.5%) in all four study arms; however, there were no statistically significant differences in this change between placebo and the three treatment arms. No dose-dependent relationship in treatment effect was observed for any of the study endpoints. The incidence of treatment-emergent adverse events (TEAEs) was revexepride dose-dependent. Only one serious TEAE occurred and none resulted in death.

CONCLUSIONS

Revexepride was no more effective than placebo in controlling regurgitation in patients with GERD symptoms partially responsive to PPIs. Revexepride was well tolerated. ClinicalTrials.gov Identifier: NCT01472939.