Application of Lyon Consensus criteria for GORD diagnosis: evaluation of conventional and new impedance-pH parameters

Topical Protection of Esophageal Mucosa as a New Treatment of GERD

Among the various factors implicated in the pathogenesis of gastroesophageal reflux disease (GERD), visceral hypersensitivity and mucosal resistance have been recently re-evaluated in relation to the increasing phenomenon of proton pump inhibitor failure, particularly in patients with nonerosive reflux disease (NERD). Intensive research has allowed us to understand that noxious substances contained in the refluxate are able to interact with esophageal epithelium and to induce the elicitation of symptoms. The frequent evidence of microscopic esophagitis able to increase the permeability of the mucosa, the proximity of sensory afferent nerve fibers to the esophageal lumen favoring the higher sensitivity to noxious substances and the possible activation of inflammatory pathways interacting with sensory nerve endings are pathophysiological alterations confirming that mucosal resistance is impaired in GERD patients. Accordingly, the reinforcement of protective mechanisms of esophageal mucosa by topical therapies has become a novel treatment target. Alginate, the combination of hyaluronic acid+chondroitin sulphate and Poliprotect have been shown to adhere to esophageal mucosa and to have good protective properties. Several placebo-controlled clinical trials have shown that these compounds, given alone or as add-on therapy for short periods, enable to relieve symptoms and to improve the quality of life in NERD patients. Further studies are needed to confirm the above results and to find new mucosal protectants in order to improve the management of NERD patients.

Mean Nocturnal Baseline Impedance May Be Greater Than 2500 Ohms in Chinese Patients With GERD

BACKGROUND

According to the Lyon Consensus 2.0, mean nocturnal baseline impedance (MNBI) greater than 2500 Ω is considered evidence against gastroesophageal reflux disease (GERD). However, we have observed that a subset of GERD patients presents with MNBI exceeding 2500 Ω.

AIMS

To investigate MNBI characteristics in Chinese GERD patients, identify clinical features of those with normal MNBI, and examine factors influencing MNBI values.

METHODS

We retrospectively investigated 259 patients with typical reflux symptoms. Demographics, symptoms, proton pump inhibitor (PPI) response, esophageal motility parameters were compared between patients with different AET levels and MNBI levels.

RESULTS

Among the cohort, 38.2% had AET 4%-6%, and 37.5% had AET > 6%. Notably, 95.2% of patients with AET < 4%, 49.5% with AET 4%-6%, and 17.6% with AET > 6% had MNBI > 2500 Ω. Independent risk factors for MNBI > 2500 Ω included the number and duration of supine acid reflux and lower esophageal sphincter (LES) resting pressure. In GERD patients with heartburn, patients with MNBI ≤ 2500 Ω had higher PPI response than MNBI > 2500 Ω (81.1% vs. 55.6%, p = 0.009).

CONCLUSIONS

Approximately one-third of Chinese GERD patients have an MNBI > 2500 Ω. The thresholds of MNBI for supporting or ruling out GERD in the Chinese population should be adjusted. MNBI values are independently predicted by the severity of supine acid reflux and the LES resting pressure. GERD patients with mild supine acid reflux may still exhibit normal MNBI levels. Patients with lower MNBI values tend to show better responses to PPI therapy.

The Contemporary Diagnostic Approaches to Esophageal Symptomatology

Esophageal symptoms, including dysphagia, heartburn, and non-cardiac chest pain, are prevalent concerns in gastroenterology. This review examines the roles of advanced diagnostic modalities such as high-resolution manometry (HRM), pH-impedance monitoring, and EndoFLIP in understanding esophageal physiology and pathology. Here, we discuss the clinical presentations of common esophageal symptoms and explore how structural abnormalities like strictures and motility disorders, including achalasia and esophageal spasms, are assessed using these tools. The diagnostic utility of endoscopy in visualizing mucosal and structural changes is highlighted alongside emerging technologies like artificial intelligence in enhancing detection capabilities. Complementary techniques, such as barium esophagrams and reflux monitoring, provide additional functional and anatomical insights, crucial for comprehensive patient evaluation. The integration of these diagnostic approaches fosters a deeper understanding of esophageal disorders, guiding effective management strategies and improving patient outcomes. This review aimed to highlight the importance of adopting a multimodal diagnostic approach in modern gastroenterological practice.

Esophageal chest pain resembles heartburn in reflux metrics and response to proton pump inhibitor therapy

BACKGROUND

Gastro-esophageal reflux disease (GERD) is the most common cause for noncardiac chest pain (NCCP), with an estimated prevalence rate ranging between 30% and 60%. Heartburn and NCCP may share common mechanisms.

AIMS/METHODS

To assess whether particular patterns of impedance-pH variables characterize patients with dominant heartburn, regurgitation, or NCCP and their ability to predict proton pump inhibitor (PPI) response for each symptom, GERD patients, evaluated with high-resolution manometry (HRM) and impedance-pH, were included.

RESULTS

In total, 109 NCCP, 68 heartburn, and 64 regurgitation patients were included. Pathological reflux episodes were observed in 28%, 19%, and 56% (p < 0.001). Pathological mean nocturnal baseline impedance (MNBI) values were observed in 55%, 53%, and 34% (p < 0.05). Hypomotility was more frequent in NCCP compared to heartburn patients (p < 0.05). When comparing NCCP with heartburn, hypomotility was associated with NCCP perception (OR: 2.34, 95% CI: 1.23-4.43; p < 0.01). When comparing NCCP with regurgitation, >80 refluxes and type 2/3 esophagogastric junction (EGJ) were associated with regurgitation perception (OR: 0.31, 95% CI: 0.16-0.59; p < 0.001, and OR: 0.5, 95% CI: 0.27-0.93; p < 0.05), while pathological MNBI was associated with NCCP perception (OR: 2.34, 95% CI: 1.23-4.43; p < 0.01). 45.5% NCCP patients, 45.6% with heartburn, and 36% with regurgitation responded to PPIs (p < 0.05). At multivariate analysis, pathological MNBI or PSPW index were associated with PPI responsiveness in patients with NCCP or heartburn, while in patients with regurgitation, pathological MNBI was associated with PPI responsiveness and a reflux number >80 to PPI refractoriness.

CONCLUSIONS

We highlight the usefulness of an accurate clinical and functional evaluation of GERD patients, allowing to discriminate particular characteristics in patients with dominant heartburn, NCCP, or regurgitation, which may benefit of distinct therapeutic strategies.

Post-reflux swallow-induced peristaltic wave index and mean nocturnal baseline impedance predict proton pump inhibitor response in patients with reflux hypersensitivity

BACKGROUND AND AIM

Post-reflux swallow-induced peristaltic wave (PSPW) index and mean nocturnal baseline impedance (MNBI) have been shown to influence proton pump inhibitor (PPI) response in GERD patients. However, currently, little data concerning these variables in patients with reflux hypersensitivity (RH) are available. In this study, we aimed to evaluate, in RH patients, the prevalence of PPI responders and nonresponders and investigate the predictive value of impedance-pH variables, including PSPW and MNBI, on responses to PPI.

METHODS

A total of 108 RH patients who met ROME IV criteria were prospectively recruited from June 2018 to December 2022. The prevalence of PPI responders/nonresponders was calculated, and impedance-pH variables were compared between the response and nonresponse groups. Multiple logistic regression was used to investigate predictors for PPI response.

RESULTS

Among 108 patients with RH, 60 patients (55.56%) were the PPI responders, and 48 (44.44%) were the nonresponders. Compared with the nonresponders, the PPI responders had a lower PSPW index (47.05 ± 4.43 vs 51.33 ± 3.50, P = 0.004) and a decreased value of MNBI (1866.68 ± 390.62 vs 2181.14 ± 338.42, P = 0.017). Multivariate logistic regression revealed that only the pathologic PSPW index (OR: 2.064) and MNBI (OR: 1.800) significantly influenced PPI response.

CONCLUSIONS

Nearly half of RH patients were PPI nonresponders. Impedance-pH monitoring was more valuable than pH-only monitoring in associating PPI response to reflux in RH patients owing to the appraisal of the PSPW index and MNBI.

pHoenix score: development and validation of a novel approach to decrease the number of inconclusive GERD diagnoses

BACKGROUND

The Johnson-DeMeester composite score (DMS) is the historical gold standard for diagnosing gastroesophageal reflux disease (GERD). The Lyon Consensus outlines criteria for diagnosing GERD by pH monitoring, defining normal acid exposure time (AET) as < 4% and pathological as > 6%, presenting diagnostic uncertainty from 4 to 6%. We aimed to (i) calculate the proportion of borderline studies defined by total AET alone that are reclassified as normal or pathological by the DMS, (ii) determine the importance of supine AET for reclassification, and (iii) propose a new classification system using a composite score that considers positional changes.

METHODS

This single-center, retrospective, observational study analyzed data from patients with an overall total AET from 2 to 6% on 48-h pH monitoring (Bravo pH capsule). Preselected predictors (supine and upright AET) were included in a model to create a composite score (i.e., pHoenix score) using the regression coefficients. The model was internally validated, and discriminative ability was tested against the DMS and compared to the total AET.

RESULTS

We identified 114 patients (80 [70.2%] women; median age, 55 years). Using the total AET, 26 (22.8%) were classified as normal and 88 (77.2%) as borderline; however, using the DMS, 45 (39.5%) were classified as normal and 69 (60.5%) as pathological. The new pHoenix score demonstrated strong discriminative ability (AUC: 0.957 [95% CI 0.917, 0.998]) with high sensitivity and specificity (lower threshold, 94.4% and 79.2%; upper threshold, 87 and 95.8%). Compared to the total AET alone, the pHoenix score significantly decreased the proportion of inconclusive cases (77.2% vs. 13.2%, p < 0.001).

CONCLUSION

Total AET has low sensitivity to identify pathological reflux as it disregards supine versus upright reflux. The pHoenix score improves the distinction between normal and pathological cases and reduces ambiguity, offering an alternative approach to diagnosing GERD that addresses the limitations of using total AET alone or the DMS.

The Clinical Spectrum of Gastroesophageal Reflux Disease: Facts and Fictions

Background

This review addresses the intricate spectrum of gastroesophageal reflux disease (GERD), a condition affecting 10-30% of the Western population. GERD is characterized by the backflow of gastric contents into the esophagus, causing typical and atypical symptoms. Its pathophysiology involves various factors such as hiatal hernia, esophageal motor disorders, and dietary triggers. The review explores the complexities of GERD spectrum, including nonerosive reflux disease (NERD), reflux hypersensitivity (RH), and functional heartburn (FH).

Summary

The diagnostic process for GERD, based on the Lyon Consensus 2.0 criteria, encompasses clinical evaluation, endoscopy, and functional tests, including pH-impedance and wireless-pH monitoring. NERD, a significant subset of GERD, is defined by reflux symptoms and abnormal reflux burden without mucosal damage. RH, classified under functional esophageal disorders by Rome IV criteria, presents with typical esophageal symptoms associated with reflux but lacks of structural, inflammatory, or motor causes. FH is identified by heartburn with normal endoscopy, reflux testing, and esophageal manometry results. The management of RH and FH, focusing on reducing esophageal hypersensitivity, varies from standard GERD treatments.

Key Messages

The review emphasizes the necessity of personalized treatment strategies due to the complexity and overlap of GERD subtypes. It highlights the importance of a multidisciplinary approach, involving gastroenterologists, psychologists, and other specialists, to improve patient outcomes and quality of life. The article underscores that understanding the distinctions and overlaps among NERD, RH, and FH is crucial for effective management, and the need for innovative approaches in diagnosis and treatment to address the unique challenges of each subtype.

Optimizing the Management Algorithm for Heartburn in General Gastroenterology: Cost-Effectiveness and Cost-Minimization Analysis

BACKGROUND AND AIMS

Heartburn is the most common symptom seen in gastroenterology practice. We aimed to optimize cost-effective evaluation and management of heartburn.

METHODS

We developed a decision analytic model from insurer and patient perspectives comparing 4 strategies for patients failing empiric proton pump inhibitors (PPIs): (1) PPI optimization without testing, (2) endoscopy with PPI optimization for all patients, (3) endoscopy with PPI discontinuation when erosive findings are absent, and (4) endoscopy/ambulatory reflux monitoring with PPI discontinuation as appropriate for phenotypic management. Health outcomes were respectively defined on systematic reviews of clinical trials. Cost outcomes were defined on Centers for Medicare and Medicaid Services databases and commercial multipliers for direct healthcare costs, and national observational studies evaluating healthcare utilization. The time horizon was 1 year. All testing was performed off PPI.

RESULTS

PPI optimization without testing cost $3784/y to insurers and $3128 to patients due to lower work productivity and suboptimal symptom relief. Endoscopy with PPI optimization lowered insurer costs by $1020/y and added 11 healthy days/y by identifying erosive reflux disease. Endoscopy with PPI discontinuation added 11 additional healthy days/y by identifying patients without erosive reflux disease that did not need PPI. By optimizing phenotype-guided treatment, endoscopy/ambulatory reflux monitoring with a trial of PPI discontinuation was the most effective of all strategies (gaining 22 healthy days/y) and saved $2183 to insurers and $2396 to patients.

CONCLUSIONS

Among patients with heartburn, endoscopy with ambulatory reflux monitoring (off PPI) optimizes cost-effective management by matching treatment to phenotype. When erosive findings are absent, trialing PPI discontinuation is more cost-effective than optimizing PPI.

Utility of mean nocturnal baseline impedance and post-reflux swallow-induced peristaltic wave index in clinical pH-impedance reflux study

BACKGROUND AND AIMS

Analysis of mean nocturnal baseline impedance (MNBI) and post-reflux swallow-induced peristaltic wave index (PSPWi) have been proposed to increase the diagnostic yield of pH-impedance studies in reflux disease. However, routine use of these indices in clinical studies is yet to be established, particularly with PSPWi, which requires laborious manual analysis. Our study aimed to assess the utility of MNBI and PSPWi and their potential for future incorporation into clinical practice.

METHODS

pH-impedance recordings from consecutive patients referred to the Motility Laboratory at Royal Adelaide Hospital for evaluation of gastro-oesophageal reflux disease (GORD) were prospectively collected and manually analysed. Baseline demographic characteristics, symptoms, acid exposure time (AET), number of reflux episodes, and MNBI and PSPWi were collected.

RESULTS

Eighty-nine patients were included in the study (age 50 ± 17 years, 35 males). MNBI and PSPWi inversely correlated with AET (R = -0.678, P < 0.0001 and R = -0.460, P < 0.0001 respectively) and with reflux episodes (R = -0.391, P = 0.0002 and R = -0.305, P = 0.0037 respectively). In patients with a negative pH study, but with typical reflux symptoms, 4/30 (13%) had pathologic MNBI and PSPWi. There was a positive correlation between MNBI and PSPWi values (R = 0.525, P < 0.0001). Performing analysis of PSPWi was substantially more laborious than MNBI.

CONCLUSION

MNBI and PSPWi are both useful adjuncts in the diagnosis of reflux disease, although in our cohort MNBI showed stronger correlation with AET with less time to analyse. The role of these indices remains to be further explored, particularly in patients with inconclusive AET and in those with positive compared to negative symptom association.

A prediction model of abnormal acid reflux in gastroesophageal reflux disease

BACKGROUND AND AIM

The measurement of esophageal acid exposure time (AET) using combined multichannel intraluminal impedance-pH (MII-pH) tests is the gold standard for diagnosing gastroesophageal reflux disease (GERD). However, this catheter-based 24-h test can cause considerable patient discomfort. Our aim is to identify factors affecting AET and to develop a scoring model for predicting AET abnormalities before conducting the MII-pH test.

METHODS

Of the 366 patients who underwent MII-pH test at two facilities in Japan and Vietnam, 255 patients who also had esophagogastroduodenoscopy and high-resolution manometry were included in this study. Logistic regression analysis was conducted using risk factors for AET > 6% identified from a derivation cohort (n = 109). A scoring system predicting AET > 6% was then constructed and externally validated with a separate cohort (n = 146).

RESULTS

Three variables were derived from the prediction model: male gender, Hill grades III-IV, and weak mean distal contractile integrals. Based on these scores, patients were classified into low (0 point), intermediate (1-3 points), and high (4 points) risk groups. The probabilities of having an AET > 6% were 6%, 34%, and 100% for these groups, respectively. A score of < 1 excluded patients with abnormal AET, with a negative predictive value of 93.8% in the derivation cohort and 80.0% in the validation cohort.

CONCLUSIONS

We derived and externally validated a prediction model for abnormal AET. This system could assist in guiding the appropriate treatment strategies for GERD.

Automated software-derived supine baseline impedance is highly correlated with manual nocturnal baseline impedance for the diagnosis of GERD

BACKGROUND

Mean nocturnal baseline impedance (MNBI) can improve diagnostic accuracy for gastroesophageal reflux disease (GERD), but must be manually calculated and is not routinely reported. We aimed to determine how automated software-derived mean supine baseline impedance (MSBI), a potential novel GERD metric, is related to MNBI.

METHODS

Consecutively obtained pH-impedance studies were assessed. Manually extracted MNBI was compared to MSBI using paired t-test and Spearman's correlations.

KEY RESULTS

The correlation between MNBI and MSBI was very high (ρ = 0.966, p < 0.01).

CONCLUSIONS & INFERENCES

The ease of acquisition and correlation with MNBI warrant the routine clinical use and reporting of MSBI with pH-impedance studies.

Mucosal impedance as a diagnostic tool for gastroesophageal reflux disease: an update for clinicians

Mucosal impedance is a marker of esophageal mucosal integrity and a novel technique for assessing esophageal function and pathology. This article highlights its development and clinical application for gastroesophageal reflux disease (GERD), Barrett's esophagus, and eosinophilic esophagitis. A narrative review of key publications describing the development and use of mucosal impedance in clinical practice was conducted. A low mean nocturnal baseline impedance (MNBI) has been shown to be an independent predictor of response to anti-reflux therapy. MNBI predicts medication-responsive heartburn better than distal esophageal acid exposure time. Patients with equivocal evidence of GERD using conventional methods, with a low MNBI, had an improvement in symptoms following the initiation of PPI therapy compared to those with a normal MNBI. A similar trend was seen in a post fundoplication cohort. Strong clinical utility for the use of mucosal impedance in assessing eosinophilic esophagitis has been repeatedly demonstrated; however, there is minimal direction for application in Barrett's esophagus. The authors conclude that mucosal impedance has potential clinical utility for the assessment and diagnosis of GERD, particularly when conventional investigations have yielded equivocal results.

Comparison of Esophageal Dysmotility and Reflux Burden in Patients with Different Metabolic Obesity Phenotypes Based on High-Resolution Impedance Manometry and 24-h Impedance-pH

INTRODUCTION

The relationship between the metabolically healthy obesity (MHO) phenotype and the occurrence of gastroesophageal reflux disease (GERD) and inefficient esophageal motility (IEM) is still unclear. Thus, we assessed the association between different metabolic obesity phenotypes and GERD and IEM using empirical data.

METHODS

We collected clinical and test data of 712 patients, including 24-h multichannel intraluminal impedance-pH (24-h MII-pH) monitoring, high-resolution manometry (HRM), and endoscopy. We divided 567 individuals into four categories according to their metabolic obesity phenotype: metabolically unhealthy non-obesity (MUNO), metabolically unhealthy obesity (MUO), metabolically healthy non-obesity (MHNO), and MHO. We compared differences in the 24-h MII-pH monitoring, HRM, and endoscopy findings among the four metabolic obesity phenotypes.

RESULTS

Patients with the MUNO, MHO, or MUO phenotype showed a greater risk of IEM and GERD (pathologic acid exposure time [AET] >6%) compared with patients with the MHNO phenotype. Regarding the HRM results, patients with the MHNO or MUNO phenotype had a lower integrated relaxation pressure, esophageal sphincter pressure, and esophagogastric junction contractile integral, and more ineffective swallows than patients with the MHO or MUO phenotype (p < 0.05). In terms of 24-h MII-pH, patients with the MHO or MUO phenotype had a higher total, upright, and supine AET; a higher total number of reflux episodes (TRs); and a lower mean nocturnal baseline impedance and post-reflux swallow-induced peristaltic wave index compared with those with the MHNO or MUNO phenotype (all p < 0.05). Considering the odds ratio of 19.086 (95% confidence interval 6.170-59.044) for pathologic AET and 3.659 (95% confidence interval 1.647-8.130) for IEM, patients with the MUO phenotype had the greatest risk after adjusting for all confounding variables.

CONCLUSION

Obesity and metabolic disorders increase the risk of GERD and IEM. Obesity has a greater impact on esophageal dysmotility and pathologic acid exposure than metabolic diseases.

The Revised Reflux Symptom Index (R-RSI): Development, Internal and External Validation Study

INTRODUCTION

This study proposes a revised version of the Reflux Symptom Index (R-RSI), a seventeen-item questionnaire that was revised to increase the suspicion of laryngopharyngeal reflux disease (LPRD).

METHODS

Internal validation involved 213 participants, comprising 160 subjects without a previous LPRD diagnosis and 53 subjects with a self-reported previous diagnosis of LPRD with or without gastroesophageal reflux disease (GERD). Test-retest reliability and internal consistency were calculated. For the external validation, 56 patients (independent from the previous cohort) were enrolled to explore the R-RSI screening properties and determine a cutoff using 24-h MII-pH as the gold standard.

RESULTS

R-RSI test-retest reliability was high, both for the total score (ICC: 0.970) and for each item (ranging from 0.876 to 0.980). Cronbach's alpha was 0.910, indicating excellent internal consistency of the questionnaire. Participants with a previous self-reported diagnosis scored significantly higher (mean 24.94 ± 7.4; median 26, IQR 20-29) than those without a previous diagnosis (mean 4.66 ± 5.3; median 4, IQR 1-6) (p value <0.0001). Participants with both previous LPRD and GERD diagnoses had higher scores (27.20 ± 7.8) compared to those with only LPRD (21.77 ± 5.5) (p value = 0.003). Using 24-h MII-pH diagnosis as a gold standard, the optimal R-RSI cutoff point was determined to be 18, with a sensitivity of 84.5% and a specificity of 81.8%, positive predictive value of 95%, and negative predictive value of 60%.

CONCLUSIONS

Our results suggest that the R-RSI may be useful to suspect LPRD, with or without GERD. The R-RSI is a self-administered patient-reported outcome questionnaire that demonstrates excellent reliability and high screening properties. Employing a cutoff of ≥18 in the R-RSI can assist in diagnosing and monitoring LPRD.

Mean nocturnal baseline impedance in gastro-esophageal reflux disease diagnosis: Should we strictly follow the Lyon 2 Consensus?

Clinical practice guidelines drive clinical practice and clinicians rely to them when trying to answer their most common questions. One of the most important position papers in the field of gastro-esophageal reflux disease (GERD) is the one produced by the Lyon Consensus. Recently an updated second version has been released. Mean nocturnal baseline impedance (MNBI) was proposed by the first Consensus to act as supportive evidence for GERD diagnosis. Originally a cut-off of 2292 Ohms was proposed, a value revised in the second edition. The updated Consensus recommended that an MNBI < 1500 Ohms strongly suggests GERD while a value > 2500 Ohms can be used to refute GERD. The proposed cut-offs move in the correct direction by diminishing the original cut-off, nevertheless they arise from a study of normal subjects where cut-offs were provided by measuring the mean value ± 2SD and not in symptomatic patients. However, data exist that even symptomatic patients with inconclusive disease or reflux hypersensitivity (RH) show lower MNBI values in comparison to normal subjects or patients with functional heartburn (FH). Moreover, according to the data, MNBI, even among symptomatic patients, is affected by age and body mass index. Also, various studies have proposed different cut-offs by using receiver operating characteristic curve analysis even lower than the one proposed. Finally, no information is given for patients submitted to on-proton pump inhibitors pH-impedance studies even if new and extremely important data now exist. Therefore, even if MNBI is an extremely important tool when trying to approach patients with reflux symptoms and could distinguish conclusive GERD from RH or FH, its values should be interpreted with caution.

Utility of the Post-Reflux Swallow-Induced Peristaltic Wave Index and Mean Nocturnal Baseline Impedance for the Diagnosis of Gastroesophageal Reflux Disease Phenotypes in Children

(1) Objectives: Assessment of novel impedance parameters such as the post-reflux swallow-induced peristaltic wave (PSPW) index and mean nocturnal baseline impedance (MNBI) have been proposed to enhance the accuracy of gastroesophageal reflux disease (GERD) diagnosis. We aimed to evaluate the clinical value of MNBI and the PSPW index in discerning different phenotypes of GERD in children. (2) Methods: We conducted a prospective, observational study that included 49 children aged 5-18 years, referred for MII-pH monitoring due to negative endoscopy and persisting gastroesophageal reflux symptoms despite acid-suppressant treatment. The PSPW index and MNBI were assessed along with conventional metrics. (3) Results: Using a receiver operating characteristic (ROC) curve analysis, MNBI (AUC 0.864) and the PSPW index (AUC 0.83) had very good performance in differentiating between non-erosive reflux disease (NERD) and functional phenotypes. The PSPW index (AUC 0.87) discriminated better between functional heartburn (FH) and reflux hypersensitivity (RH) compared to the MNBI (AUC 0.712). A PSPW cut-off value of 65% provided a sensitivity of 76.9% and a specificity of 90% in distinguishing FH and RH. The PSPW index (AUC 0.87) proved to have better performance than the MNBI (AUC 0.802) in differentiating between FH and non-FH patients. MNBI diagnosed FH with a sensitivity of 84% and a specificity of 80.6% at a cut-off value of 2563 Ω. (4) Conclusions: The PSPW index and MNBI are useful to distinguish between GERD phenotypes in pediatric patients.

Differences Between Patients with Heartburn Refractory to Vonoprazan and Those Refractory to Proton Pump Inhibitors

BACKGROUND

Vonoprazan, a potassium-competitive acid blocker, demonstrates more potent acid inhibition than proton pump inhibitors (PPIs). This study aimed to evaluate the effect of vonoprazan in patients with unproven gastroesophageal reflux disease (GERD) by comparing patients with vonoprazan-refractory heartburn with those with PPI-refractory heartburn.

METHODS

This study included 104 consecutive patients with vonoprazan- or PPI-refractory heartburn (52 patients each), no erosive esophagitis on endoscopy and who underwent combined multichannel intraluminal impedance-pH (MII-pH) testing with vonoprazan/PPI discontinuation. Patients' backgrounds, symptom scores from four questionnaires, MII-pH results and high-resolution manometry results were compared between the two groups.

RESULTS

The vonoprazan group demonstrated significantly higher GERD symptoms and scores of abdominal pain and diarrhea on the Gastrointestinal Symptom Rating Scale questionnaire. MII-pH results revealed that the vonoprazan group demonstrated 40.4%, 17.3%, and 42.3% and the PPIs group exhibited 26.9%, 17.3%, and 55.8% of abnormal acid reflux [true non-erosive reflux disease (NERD)], reflux hypersensitivity and functional heartburn, respectively. The vonoprazan group demonstrated higher true NERD rates but with no significant difference (p = 0.307). Among the vonoprazan group, eight patients with true NERD underwent another MII-pH test on vonoprazan, and all cases demonstrated normal acid exposure times (0.0% [0.0-0.3]).

CONCLUSION

Patients with unproven GERD with vonoprazan-refractory heartburn demonstrated more symptoms, including not only GERD symptoms but also functional dyspepsia and irritable bowel syndrome symptoms, than those with PPI-refractory heartburn.

Does severe and chronic esophageal distension by air (observed in SGB and GB) affect the esophageal mucosa integrity (MNBI)

BACKGROUND

Supragastric belching (SGB) and aerophagia are behavioral disorders characterized by air induced esophageal distension. SGB is known to be associated with Gastro Esophageal Reflux Disease (GERD). Low Mean Nocturnal Baseline Impedance (MNBI) values support GERD diagnosis. We aimed to assess if chronic esophageal distension by air affects the esophageal mucosa integrity by assessing changes in MNBI.

METHODS

In a single-center database study, we searched retrospectively for patients with a diagnosis of pathological SGB (n = 146) or aerophagia (n = 34) based on impedance-pH reflux monitoring. During the examined period, patients with a conclusive negative diagnosis of SGB and no evidence of aerophagia were used as a control cohort (n = 191). MNBI at 3, 5, and 17 cm over Lower Esophageal Sphincter (LES) was evaluated. GERD was diagnosed if acid exposure time (AET) >6%. All impedance studies of included patients were prospectively reevaluated.

RESULTS

GERD was diagnosed in 31.7% patients with SGB, a rate not different in comparison to patients without SGB (30.8%, p = 0.906). MNBI at 3 and 5 cm above the LES was significantly decreased among patients with SGB. SGB was not correlated with MNBI at 3 cm over the LES, (p: 0.086 OR: 1.000 95% CI: 0.999-1.001) when using multivariate analysis. Moreover no difference was spotted as far as MNBI at 3, 5, and 17 cm over the LES is concerned among patients with or without aerophagia.

CONCLUSION

Even if patients with SGB do show lower MNBI values, esophageal distention due to excessive air movement does not directly lead to impairment of esophageal mucosa integrity.

De Novo Gastroesophageal Reflux Disease Symptoms Are Infrequent after Sleeve Gastrectomy at 2-Year Follow-Up Using a Comprehensive Preoperative Esophageal Assessment

Pathological obesity is a growing public health concern, and its association with gastroesophageal reflux disease (GERD) poses challenges in selecting the appropriate bariatric procedure. Sleeve gastrectomy (SG) has become a popular choice due to its simplicity and effectiveness in weight loss. However, concerns regarding postoperative GERD have been raised. This study aimed to evaluate the association between preoperative assessment of esophageal function and the risk of developing postoperative GERD in patients undergoing SG. A comprehensive evaluation was conducted, including symptom assessment, upper endoscopy, high-resolution esophageal manometry (HRM), and 24 h esophageal pH impedance monitoring (MII-pH). A total of 500 obese patients were included, and their data were compared with 25 healthy volunteers. This study revealed that patients without GERD symptoms, normal endoscopy, HRM, and MII-pH were suitable candidates for SG, with low risk of developing postoperative GERD. The addition of fundoplication techniques to SG may be considered in patients with mild reflux or those at risk of developing it. This study emphasizes the importance of preoperative evaluation in selecting the appropriate bariatric procedure to minimize the risk of postoperative GERD and expand the indications for SG in obese patients.

Updates to the modern diagnosis of GERD: Lyon consensus 2.0

The Lyon Consensus provides conclusive criteria for and against the diagnosis of gastro-oesophageal reflux disease (GERD), and adjunctive metrics that consolidate or refute GERD diagnosis when primary criteria are borderline or inconclusive. An international core and working group was assembled to evaluate research since publication of the original Lyon Consensus, and to vote on statements collaboratively developed to update criteria. The Lyon Consensus 2.0 provides a modern definition of actionable GERD, where evidence from oesophageal testing supports revising, escalating or personalising GERD management for the symptomatic patient. Symptoms that have a high versus low likelihood of relationship to reflux episodes are described. Unproven versus proven GERD define diagnostic strategies and testing options. Patients with no prior GERD evidence (unproven GERD) are studied using prolonged wireless pH monitoring or catheter-based pH or pH-monitoring off antisecretory medication, while patients with conclusive GERD evidence (proven GERD) and persisting symptoms are evaluated using pH-impedance monitoring while on optimised antisecretory therapy. The major changes from the original Lyon Consensus criteria include establishment of Los Angeles grade B oesophagitis as conclusive GERD evidence, description of metrics and thresholds to be used with prolonged wireless pH monitoring, and inclusion of parameters useful in diagnosis of refractory GERD when testing is performed on antisecretory therapy in proven GERD. Criteria that have not performed well in the diagnosis of actionable GERD have been retired. Personalisation of investigation and management to each patient's unique presentation will optimise GERD diagnosis and management.

Post-reflux swallow-induced peristaltic wave index: a new parameter for the identification of non-acid gastroesophageal reflux-related chronic cough

BACKGROUND

The current available diagnostic criteria for gastroesophageal reflux-related chronic cough (GERC) dominated by non-acid reflux is imperfect. The post-reflux swallow-induced peristaltic wave index (PSPWI) is a parameter reflecting esophageal clearance function.

OBJECTIVES

This study aims to investigate its diagnostic value for non-acid GERC.

DESIGN

This study sought to compare the diagnostic value of PSPWI in different types of GERC, particularly non-acid GERC, and explore the clinical significance of PSPWI in the diagnosis of non-acid GERC through diagnostic experiments.

METHODS

A retrospective analysis was performed based on 223 patients with suspected GERC who underwent multichannel intraluminal impedance-pH monitoring (MII-pH) in the outpatient clinic of our department from August 2016 to June 2021. Their clinical information, laboratory test results, and treatment responses were assessed and the underlying etiologies of chronic cough were categorized. The predictive value of the PSPWI in diagnosing different types of GERC, especially non-acid GERC, was analyzed and compared.

RESULTS

A total of 195 patients with chronic cough who met the inclusion criteria underwent MII-pH monitoring. 143 patients had a definitive diagnosis of GERC, including 98 with acid GERC and 45 with non-acid GERC. The diagnostic value of PSPWI alone was moderate for GERC with an area under the working curve (AUC) 0.760, but poor for non-acid GERC with an AUC of 0.569. However, PSPWI < 39.8% combining with acid exposure time (AET) ⩽ 6.2% demonstrated a moderate diagnostic value for non-acid GERC, with an AUC of 0.722. When PSPWI < 39.8% combined with a non-acid reflux ratio >68.75%, the diagnostic value for non-acid GERC was improved (AUCROC = 0.80 versus AUCROC = 0.722, p < 0.05), which was significantly superior to non-acid symptom index (AUCROC = 0.804 versus AUCROC = 0.550, p < 0.05) and non-acid symptom association probability (AUCROC = 0.804 versus AUCROC = 0.571, p < 0.05).

CONCLUSION

PSPWI < 39.8% and AET ⩽ 6.2% have demonstrated good diagnostic value for non-acid GERC. The diagnostic value was further improved when combined with non-acid reflux ratio >68.75%.

Esophageal Reflux Hypersensitivity: A Comprehensive Review

Reflux hypersensitivity (RH) is one of the phenotypes of gastroesophageal reflux disease. The latest Rome IV defines RH as a condition with typical reflux symptoms and positive reflux-symptom association despite normal acid exposure. Subsequently, the Lyon consensus proposed detailed cutoff values for the criteria on the basis of experts' consensus. Rome IV brought a clear-cut perspective into the pathophysiology of gastroesophageal reflux disease and the importance of esophageal hypersensitivity. This perspective can be supported by the fact that other functional gastrointestinal disorders such as irritable bowel syndrome and functional dyspepsia often overlap with RH. Although several possible pathophysiological mechanisms of esophageal hypersensitivity have been identified, there is still unmet medical needs in terms of treatment for this condition. This review summarizes the current knowledge regarding RH.

Effect of aging and obesity on esophageal mucosal integrity as measured by baseline impedance

AIM

Low mean nocturnal baseline impedance (MNBI) values support gastroesophageal reflux disease (GERD) diagnosis. Recent data denote that age and obesity may affect MNBI. We aimed to evaluate diagnostic MNBI cutoffs as also the effect of aging and body mass index (BMI) on MNBI.

METHODS

In total 311 patients (M/F: 139/172, mean age: 47 ± 13) referred for typical GERD symptoms that have undertaken both high-resolution manometry (HRM) and pH-Impedance studies off PPI were evaluated. MNBI at 3, 5, and 17 cm over lower esophageal sphincter (LES) were evaluated. GERD was diagnosed if acid exposure time (AET) >6%.

RESULTS

Mean BMI was 26.6 ± 5.9 kg/cm2 . GERD was diagnosed in 39.2% and 13.5% had inconclusive GERD. MNBI was correlated to patients' age, BMI, AET, and the length of LES-CD separation and at 3 cm also to the total number of reflux and LES hypotension. In the multivariate analysis MNBI at 3 and 5 cm was independently correlated only to age, BMI, and AET. Patients with definite GERD showed lower MNBI at 3 cm compared with inconclusive GERD though both showed lower values when compared with GERD absence. At 3 cm MNBI ability for diagnosing GERD was good (0.815, p < 0.001 95% CI: 0.766-0.863) with an optimal cutoff point of 1281 Ohm.

CONCLUSION

According to our study findings age and BMI affect independently lower esophageal MNBI values in patients evaluated for GERD. MNBI significantly aids toward GERD diagnosis though in a real-life setting MNBI values much lower than the one previously proposed should be used.

Encouraging appropriate use of proton pump inhibitors: existing initiatives and proposals for the future

INTRODUCTION

Proton pump inhibitors (PPIs) have revolutionized the management of acid-related disorders, representing today the mainstay treatment of these conditions. However, despite their large range of indications and usefulness, the remarkable expansion of their use in the last two decades cannot be explained by the increasing prevalence of acid-related diseases only. An inappropriate prescription for clinical conditions in which the pathogenetic role of acid has not been documented has been described, with the natural consequence of increasing the costs and the potential risk of iatrogenic harm due to adverse events and complications recently emerged.

AREAS COVERED

In this review, we summarize current indications of PPIs administration, potential adverse events associated with their chronic utilization, and misuse of PPIs. Moreover, we describe existing and possible initiatives for improving the use of PPIs, and some proposals for the future.

EXPERT OPINION

PPI deprescribing is the preferred and most effective approach to reduce the use of PPIs, rather than adopting sharp discontinuation, probably due to fewer withdrawal symptoms. Nonetheless, large knowledge gaps still exist in clinical practice regarding the optimal approach of PPI deprescribing in various clinical scenarios. Further prospective well-designed international studies are eagerly warranted to improve our perspectives on controlling global PPI inappropriate use.

Towards a better diagnosis of gastro esophageal reflux disease

INTRODUCTION

GERD is a common disorder and is characterized by the presence of typical or atypical symptoms. In GERD patients, the presence of mucosal alterations in endoscopy is detected in up to 30% of individuals. The clinical presentation of GERD patients may be complex and their management is challenging, due to the heterogeneous clinical presentation. The present review has been performed searching all relevant articles in this field, over the past years, using PubMed database.

AREAS COVERED

The diagnosis and management of GERD have been significantly improved in the last years due to the increasing availability of reflux monitoring techniques and the implementation of new procedures in the therapeutic armamentarium. Beside traditional impedance-pH variables, new metrics have been developed, increasing the diagnostic yield of reflux monitoring and better predicting the treatment response. Traditional pharmacological treatments include acid-suppressive-therapy and/or anti-acid. On the other hand, surgical treatment and, more recently, endoscopic procedures represent a promising field in the therapeutic approach.

EXPERT OPINION

Diagnosis and treatment of GERD still represent a challenging area. However, we believe that an accurate upfront evaluation is, nowadays, necessary in addressing patients with GERD to a more accurate diagnosis as well as to the best treatment options.

Prevalence of gastroesophageal reflux disease in children with extraesophageal manifestations using combined-video, multichannel intraluminal impedance-pH study

BACKGROUND

Gastroesophageal reflux disease (GERD) might be either a cause or comorbidity in children with extraesophageal problems especially as refractory respiratory symptoms, without any best methods or criterion for diagnosing it in children.

AIM

To evaluate the prevalence of extraesophageal GERD using conventional and combined-video, multichannel intraluminal impedance-pH (MII-pH), and to propose novel diagnostic parameters.

METHODS

The study was conducted among children suspected of extraesophageal GERD at King Chulalongkorn Memorial Hospital between 2019 and 2022. The children underwent conventional and/or combined-video MII-pH. The potential parameters were assessed and receiver operating characteristic was used for the significant parameters.

RESULTS

Of 51 patients (52.9% males), aged 2.24 years were recruited. The common problems were cough, recurrent pneumonia, and hypersecretion. Using MII-pH, 35.3% of the children were diagnosed with GERD by reflux index (31.4%), total reflux events (3.9%), and symptom indices (9.8%) with higher symptom recorded in the GERD group (94 vs 171, P = 0.033). In the video monitoring group (n = 17), there were more symptoms recorded (120 vs 220, P = 0.062) and more GERD (11.8% vs 29.4%, P = 0.398) by symptom indices. Longest reflux time and mean nocturnal baseline impedance were significant parameters for diagnosis with receiver operating characteristic areas of 0.907 (P = 0.001) and 0.726 (P = 0.014).

CONCLUSION

The prevalence of extraesophageal GERD in children was not high as expected. The diagnostic yield of symptom indices increased using video monitoring. Long reflux time and mean nocturnal baseline impedance are novel parameters that should be integrated into the GERD diagnostic criteria in children.

Prospective validation of reflux monitoring by impedance-pH in predicting PPI response in typical GERD

BACKGROUND

The Lyon Consensus proposed a hierarchical approach to GERD diagnosis based on conventional and new impedance-pH metrics, namely acid exposure time (AET), number of reflux episodes, post-reflux swallow-induced peristaltic wave (PSPW) index, and mean nocturnal baseline impedance (MNBI).

AIMS

To define the value of conventional and new impedance-pH parameters as predictors of response to label-dose PPI in typical GERD.

METHODS

Consecutive adult patients with typical esophageal symptoms were prospectively studied with impedance-pH monitoring and treated with 8-week label-dose PPI. At the end of the PPI course, symptoms response was assessed.

RESULTS

Among 255 patients who entered the study, 168 (65.9%) reported symptom remission. At ROC analysis, both MNBI and PSPW index were significantly associated to PPI responsiveness with AUC of 0.783 and 0.801, respectively. Cut-off values of 1747Ω for MNBI and 50% for PSPW index were identified as discriminators between response and non-response to label-dose PPI. At multivariate analysis, MNBI, PSPW index, and AET >6% were efficient predictors of PPI responses (OR 3, 5.4 and 2.3, respectively). Number of reflux episodes did not predict PPI response.

CONCLUSIONS

The novel MII-pH variables together with pathological are highly predictive of response of the typical GERD syndrome to label-dose PPI.

Artificial intelligence facilitates measuring reflux episodes and postreflux swallow-induced peristaltic wave index from impedance-pH studies in patients with reflux disease

BACKGROUND/AIM

Reflux episodes and postreflux swallow-induced peristaltic wave (PSPW) index are useful impedance parameters that can augment the diagnosis of gastroesophageal reflux disease (GERD). However, manual analysis of pH-impedance tracings is time consuming, resulting in limited use of these novel impedance metrics. This study aims to evaluate whether a supervised learning artificial intelligence (AI) model is useful to identify reflux episodes and PSPW index.

METHODS

Consecutive patients underwent 24-h impedance-pH monitoring were enrolled for analysis. Multiple AI and machine learning with a deep residual net model for image recognition were explored based on manual interpretation of reflux episodes and PSPW according to criteria from the Wingate Consensus. Intraclass correlation coefficients (ICCs) were used to measure the strength of inter-rater agreement of data between manual and AI interpretations.

RESULTS

We analyzed 106 eligible patients with 7939 impedance events, of whom 38 patients with pathological acid exposure time (AET) and 68 patients with physiological AET. On the manual interpretation, patients with pathological AET had more reflux episodes and lower PSPW index than those with physiological AET. Overall accuracy of AI identification for reflux episodes and PSPW achieved 87% and 82%, respectively. Inter-rater agreements between AI and manual interpretations achieved excellent for individual numbers of reflux episodes and PSPW index (ICC = 0.965 and ICC = 0.921).

CONCLUSIONS

AI has the potential to accurately and efficiently measure impedance metrics including reflux episodes and PSPW index. AI can be a reliable adjunct for measuring novel impedance metrics for GERD in the near future.

On-therapy impedance-pH monitoring can efficiently characterize PPI-refractory GERD and support treatment escalation

BACKGROUND

On-therapy impedance-pH monitoring is recommended in patients with documented GERD and PPI-refractory heartburn in order to establish whether the unremitting symptom is reflux-related or not.

AIMS

To define on-PPI cut-offs of impedance-pH metrics allowing proper interpretation of on-therapy impedance-pH monitoring.

METHODS

Blinded expert review of impedance-pH tracings performed during double-dosage PPI, prospectively collected from 150 GERD patients with PPI-refractory heartburn and 45 GERD patients with PPI-responsive heartburn but persisting extra-esophageal symptoms. Acid exposure time (AET), number of total refluxes (TRs), post-reflux swallow-induced peristaltic wave (PSPW) index, and mean nocturnal baseline impedance (MNBI) were assessed. On-PPI cut-offs were defined and evaluated with ROC analysis and the area under curve (AUC).

RESULTS

All the four impedance-pH metrics significantly differed between PPI-refractory and PPI-responsive heartburn cases. At ROC analysis, AUC was 0.73 for AET, 0.75 for TRs, 0.81 for PSPW index, and 0.71 for MNBI; best cut-offs were ≥1.7% for AET, ≥45 for TRs, ≤36% for PSPW index, and ≤ 1847 Ω for MNBI; AUC of such cut-offs was 0.66, 0.71, 0.73, and 0.68, respectively. Analysis of PSPW index and MNBI added to assessment of AET and TRs significantly increased the yield of on-therapy impedance-pH monitoring in the PPI-refractory cohort (97% vs. 83%, p < 0.0001). Notably, suboptimal acid suppression as shown by AET ≥1.7% was detected in 43% of 150 PPI-refractory cases.

CONCLUSIONS

We have defined on-PPI cut-offs of impedance-pH metrics by which comprehensive assessment of impedance-pH tracings, including analysis of PSPW index and MNBI can efficiently characterize PPI-refractory GERD and support treatment escalation.

Management of gastro-esophageal reflux disease: Practice-oriented answers to clinical questions

Gastro-esophageal reflux disease (GERD) is a condition which is frequently faced by primary care physicians and gastroenterologists. Improving management of GERD is crucial to maximise both patient care and resource utilization. In fact, the management of patients with GERD is complex and poses several questions to the clinician who faces them in clinical practice. For instance, many aspects should be considered, including the appropriateness of indication to endoscopy, the quality of the endoscopic examination, the use and interpretation of ambulatory reflux testing, and the choice and management of anti-reflux treatments, i.e., proton-pump inhibitors and surgery. Aim of the present review was to provide a comprehensive update on the clinical management of patients with GERD, through a literature review on the diagnosis and management of patients with GER symptoms. In details, we provide practice-oriented concise answers to clinical questions, with the aim of optimising patient management and healthcare resource use.

Novel Impedance-pH Parameters in Pre-Bariatric Assessment of Patients: A Pilot Study

Novel impedance-pH parameters, Mean Nocturnal Baseline Impedance (MNBI) and Post-Reflux Swallow-Induced Peristaltic Wave (PSPW) index, have been proposed to improve the gastro-esophageal reflux disease (GERD) diagnostic yield. This study aims to determine the integrity of the esophageal epithelial barrier and chemical clearance using these novel parameters and to correlate them with acid exposure time (AET) and acid clearance time (ACT) in obese patients who are candidates for bariatric surgery (BS). Twenty impedance-pHmetry tracings of patients prior to BS were reviewed. Nine (45%) patients with a conclusive diagnosis of GERD had significantly higher ACT, lower MNBI in the distal esophagus and lower PSPW indexes compared to obese patients without GERD. Moreover, 100% of obese patients with GERD had a pathological ACT compared to obese patients without GERD (p = 0.003). However, the percentage of pathological MNBI and PSPW index did not differ between obese patients with and without GERD. The PSPW index and MNBI of the distal channel significantly correlated with ACT and AET. Further studies are needed to assess the role of time-consuming novel parameters in the routine evaluation of morbidly obese patients candidates for BS. The value of acid clearance time is confirmed as a relevant impedance-pH parameter in these patients.

Association between post-reflux swallow-induced peristaltic wave index and esophageal mucosal integrity in patients with GERD symptoms

BACKGROUND

Impedance-pH monitoring allows evaluation of esophageal chemical clearance, a response to reflux elicited by the esophago-salivary reflex, by means of the post-reflux swallow-induced peristaltic wave (PSPW) index; mucosal integrity can be evaluated by means of mean nocturnal baseline impedance (MNBI) and is regarded as a GERD marker. Currently, the relationship between PSPW index and MNBI has not yet been fully investigated and represents the aim of the present study.

METHODS

Impedance-pH tracings from consecutive patients were reviewed. ROC analysis and multivariate regression models were generated to evaluate the association between acid exposure time (AET), total refluxes (TRs), PSPW index, and MNBI. Patients were classified by means of AET thresholds and symptom-reflux association indexes into conclusive and inconclusive GERD, reflux hypersensitivity (RH), and functional heartburn (FH). Pathologic MNBI <2292 Ω was defined according to published outcome studies.

KEY RESULTS

Two hundred and thirty patients constituted the study cohort. Overall, a significant direct correlation was observed between PSPW index and MNBI (0.759, p < 0.001). At ROC analysis, a PSPW index cut-off value of 53% was the best discriminator between normal from pathologic MNBI values (sensitivity 88%, specificity 86.4%). Considering AET cut-off of 4% or 6%, a sensitivity of 80.7% and 46% and a specificity of 62.5% and 93.2% were found, respectively. According to multivariate analysis, AET >4% and PSPW index value <53% or <61% were significantly associated with pathologic MNBI values.

CONCLUSIONS AND INFERENCES

Esophageal chemical clearance is a major defense mechanism against reflux and its impairment represents a major determinant of reflux-associated mucosal damage.

Mean nocturnal baseline impedance, a novel metric of multichannel intraluminal impedance-pH monitoring in diagnosing gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a common disease with increasing prevalence worldwide. However, the diagnosis of GERD is challenging because there are no definite gold standard criteria. Recently, a novel impedance parameter, namely mean nocturnal baseline impedance (MNBI), has been proposed, which reflects the burden of longitudinal reflux and the integrity of esophageal mucosa. MNBI has shown an immense promise for increasing the diagnostic rate of multichannel intraluminal impedance-pH (MII-pH) monitoring and predicting the response to proton pump inhibitor (PPI) or anti-reflux intervention in patients with reflux symptoms. The present paper reviews the association between baseline impedance and esophageal mucosal integrity, the acquisition of MNBI in 24-h MII-pH monitoring, the clinical utilization of MNBI in improving the diagnosis rate of GERD in patients with typical reflux symptoms, predicting the response to PPI or anti-reflux treatment in these patients, the utilization of MNBI in diagnosing patients with atypical symptoms or extra-esophageal symptoms, and the correlation between reflux burden and MNBI. MNBI should be routinely assessed using MII-pH monitoring.

Recent insights on functional heartburn and reflux hypersensitivity

PURPOSE OF REVIEW

Rome IV experts have proposed that gastroesophageal reflux disease (GERD) should be diagnosed only in patients with abnormal esophageal acid exposure, and that reflux hypersensitivity (RH) and functional heartburn (FH) both should be considered functional conditions separate from GERD. Although past and recent evidence support that FH can be completely distinguished from GERD, the concept that RH is not GERD is highly questionable. This review attempts to provide current data on these issues.

RECENT FINDINGS

Many recent investigations have provided new data on the different pathophysiological features characterizing RH and FH. Major differences have emerged from analyses of impedance-pH monitoring studies using the novel impedance metrics of baseline impedance (an index of mucosal integrity) and the rate of postreflux swallow-induced peristaltic waves (a reflection of the integrity of esophageal chemical clearance).

SUMMARY

The better ability to interpret impedance-pH tracings together with earlier data on the different prevalence of microscopic esophagitis in RH and FH patients, and recent studies documenting poor therapeutic efficacy of pain modulators and good results of antireflux surgery for RH support recategorization of RH within the GERD world. Further research is needed to correctly phenotype patients who have heartburn without mucosal breaks, and to guide their effective management.

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.

Editorial: Lyon consensus metrics-towards personalised diagnosis of non-erosive reflux disease: Authors' reply

This article is linked to Frazzoni et al papers. To view these articles, visit https://doi.org/10.1111/apt.16838 and https://doi.org/10.1111/apt.16899

Reduced masticatory function predicts gastroesophageal reflux disease and esophageal dysphagia in patients referred for upper endoscopy: A cross-sectional study

BACKGROUND

The role of mastication on gastroesophageal reflux disease (GERD) is unknown.

AIMS

To assess whether reduced masticatory function predicts GERD and esophageal dysphagia in patients investigated with upper endoscopy.

METHODS

In this cross-sectional study, 179 adult patients referred for elective upper gastrointestinal endoscopy agreed to participate. Before endoscopy, an expert dentist performed an oral examination and scored chewing function in three levels (normal, regular, and reduced). Patients replied questionnaires for assessment of GERD (heartburn, regurgitation, and dysphagia), xerostomia, and mastication (normal, regular, and reduced). Poor chewing was defined when either oral examination or mastication questionnaire rated the chewing function as reduced. Associations of mastication with GERD and dysphagia were estimated using Poisson regression.

RESULTS

Eleven patients were excluded. Among 168 analyzed (aging 49.8 ± 15.5 years; 58.9% women), 46 had reduced masticatory function (27.4%), and 122 had regular/normal mastication (72.6%). Reduced mastication was associated with GERD [PR = 1.38 (95%CI 1.12 - 1.70)], adjusting for age, and with esophageal dysphagia [PR = 2.03 (95%CI 1.02 - 4.04)], adjusting for age and xerostomia.

CONCLUSIONS

In outpatients referred for upper gastrointestinal endoscopy, reduced masticatory function defined by an expert dentist may be a risk factor for GERD and esophageal dysphagia.

Clinical use of mean nocturnal baseline impedance and post-reflux swallow-induced peristaltic wave index for the diagnosis of gastro-esophageal reflux disease

The clinical diagnosis of gastro-esophageal reflux disease (GERD) is based on the presence of typical esophageal troublesome symptoms. In clinical practice, heartburn relief following a proton pump inhibitor (PPI) trial or endoscopy can confirm a diagnosis of GERD. In cases of diagnostic uncertainty or before anti-reflux interventions, combined impedance-pH monitoring (MII-pH) provides a comprehensive assessment of both physical and chemical properties of the refluxate, allowing to achieve a conclusive diagnosis of GERD. Recently, the Lyon Consensus proposed the use of mean nocturnal baseline impedance (MNBI) and post-reflux swallow-induced peristaltic wave index (PSPW-I) as novel MII-pH metrics to support the diagnosis of GERD. The calculation of MNBI and PSPW-I currently needs to be performed manually, but artificial intelligence systems for the automated analysis of MII-pH tracings are being developed. Several studies demonstrated the increased diagnostic yield MNBI and PSPW-I for the categorization of patients with GERD at both on- and off-PPI MII-pH monitoring. Accordingly, we performed a narrative review on the clinical use and diagnostic yield of MNBI and PSPW-I when the diagnosis of GERD is uncertain. Based on currently available evidence, we strongly support the evaluation of PSPW-I and MNBI as part of the standard assessment of MII-pH tracings for the evaluation of GERD, especially in patients with endoscopy-negative heartburn.