Novel impedance-pH parameters are associated with proton pump inhibitor response in patients with inconclusive diagnosis of gastro-oesophageal reflux disease according to Lyon Consensus

How to diagnose GERC more effectively: reflections on post-reflux swallow-induced peristaltic wave index and mean nocturnal baseline impedance

INTRODUCTION

Post-reflux swallow-induced peristaltic wave index (PSPWI) and mean nocturnal baseline impedance (MNBI) are novel parameters reflect esophageal clearance capacity and mucosal integrity. They hold potential in aiding the recognition of gastroesophageal reflux-induced chronic cough (GERC). Our study aims to investigate their diagnostic value in GERC.

METHODS

This study included patients suspected GERC. General information and relevant laboratory examinations were collected, and final diagnosis were determined following guidelines for chronic cough. The parameters of multichannel intraluminal impedance-pH monitoring (MII-pH) in patients were analyzed and compared to explore their diagnostic value in GERC.

RESULTS

A total of 186 patients were enrolled in this study. The diagnostic value of PSPWI for GERC was significant, with the area under the working curve (AUC) of 0.757 and a cutoff value of 39.4%, which was not statistically different from that of acid exposure time (AET) (p > 0.05). The combined diagnostic value of AET > 4.4% and PSPWI < 39.4% was superior to using AET > 4.4% alone (p < 0.05). Additionally, MNBI and distal MNBI also contributed to the diagnosis of GERC, with AUC values of 0.639 and 0.624, respectively. AET > 4.4% or PSPWI < 39.4% is associated with a 44% reduction in missed diagnoses of non-acid GERC compared to AET > 6.0% or symptom association probability (SAP) ≥ 95%, and may be more favorable for identifying GERC.

CONCLUSION

The diagnostic value of PSPWI for GERC is comparable to that of AET. Combining PSPWI < 39.4% or AET > 4.4% can improve the diagnostic efficiency by reducing the risk of missed diagnoses in cases where non-acid reflux is predominant. Distal MNBI and MNBI can serve as secondary reference indices in the diagnosis of GERC.

Proximal esophageal impedance baseline increases the yield of impedance-pH and is associated with response to PPIs in chronic cough patients

BACKGROUND

Chronic cough significantly impairs the quality of life. Although various studies focused on MNBI as assessed in the distal esophagus, scarce data are available on the clinical value of proximal measurements.

AIM

To investigate the role of proximal MNBI in the workup of patients with chronic cough and its ability to predict PPI response.

METHODS

Demographic, clinical, endoscopy findings, impedance-pH and HRM tracings from consecutive cough patients were evaluated. MNBI was calculated at proximal and distal esophagus.

RESULTS

One hundred and sixty four patients were included. In addition to traditional variables, when considering also the PSPW index or MNBI at 3 cm or 15 cm, the proportion of patients with pathological impedance-pH monitoring significantly increased. 70/164 patients were responders, while 94 (57.3%) were non-responder to double PPI dose (p < 0.05). Patients with pathologic MNBI at 3 cm and/or 15 cm as well as those with pathologic PSPW index were characterized by a significantly higher proportion of responders than that observed among patients with normal impedance-pH variables (p < 0.001). The proportion of responders with pathological MNBI at 15 cm was significantly higher than the proportion of responders with pathological MNBI at 3 cm (82.8% vs. 64.3%, p < 0.05). At multivariable model, pathological MNBI at both 3 cm and 15 cm as well as PSPW index were associated with PPI responsiveness. The strongest association with PPI response was observed for MNBI at 15 cm.

CONCLUSIONS

The assessment of MNBI at proximal esophagus increases the diagnostic yield of impedance-pH monitoring and may represent a useful predictor of PPI responsiveness in the cumbersome clinical setting of suspected reflux-related cough.

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.

The Clinical Spectrum of Gastroesophageal Reflux Disease: Facts and Fictions

<b><i>Background:</i></b> 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). <b><i>Summary:</i></b> 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. <b><i>Key Messages:</i></b> 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.

Latin American consensus on diagnosis of gastroesophageal reflux disease

BACKGROUND

Diagnosing gastroesophageal reflux disease (GERD) can be challenging given varying symptom presentations, and complex multifactorial pathophysiology. The gold standard for GERD diagnosis is esophageal acid exposure time (AET) measured by pH-metry. A variety of additional diagnostic tools are available. The goal of this consensus was to assess the individual merits of GERD diagnostic tools based on current evidence, and provide consensus recommendations following discussion and voting by experts.

METHODS

This consensus was developed by 15 experts from nine countries, based on a systematic search of the literature, using GRADE (grading of recommendations, assessment, development and evaluation) methodology to assess the quality and strength of the evidence, and provide recommendations regarding the diagnostic utility of different GERD diagnosis tools, using AET as the reference standard.

KEY RESULTS

A proton pump inhibitor (PPI) trial is appropriate for patients with heartburn and no alarm symptoms, but nor for patients with regurgitation, chest pain, or extraesophageal presentations. Severe erosive esophagitis and abnormal reflux monitoring off PPI are clearly indicative of GERD. Esophagram, esophageal biopsies, laryngoscopy, and pharyngeal pH monitoring are not recommended to diagnose GERD. Patients with PPI-refractory symptoms and normal endoscopy require reflux monitoring by pH or pH-impedance to confirm or exclude GERD, and identify treatment failure mechanisms. GERD confounders need to be considered in some patients, pH-impedance can identify supragrastric belching, impedance-manometry can diagnose rumination.

CONCLUSIONS

Erosive esophagitis on endoscopy and abnormal pH or pH-impedance monitoring are the most appropriate methods to establish a diagnosis of GERD. Other tools may add useful complementary information.

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%.

Chicago Classification v4.0 Stratifies Acid Burden and Abnormal Impedance-pH Variables Better Than Chicago Classification v3.0 Chicago Classification v4.0 and GERD

INTRODUCTION

Gastroesophageal reflux disease (GERD) severity increases with esophageal body hypomotility, but the impact of Chicago Classification (CC) v4.0 criteria on GERD diagnosis is incompletely understood.

METHODS

In patients with GERD evaluated with high-resolution manometry and pH-impedance monitoring, CCv3.0 and CCv4.0 diagnoses were compared.

RESULTS

In 247 patients, hypomotility diagnosis decreased from 45.3% (CCv3.0) to 30.0% (CCv4.0, P < 0.001). In contrast, within patients with ineffective esophageal motility, proportions with pathological acid exposure increased from 38% (CCv3.0) to 88% (CCv4.0); baseline impedance and esophageal clearance demonstrated similar findings ( P < 0.05 for each comparison).

DISCUSSION

CCv4.0 hypomotility criteria are more specific in supporting GERD evidence compared with CCv3.0.

Association between Mean Nocturnal Baseline Impedance (MNBI) and Post-Reflux Swallow-Induced Peristaltic Wave Index (PSPW) in GERD Patients

Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal disorders in the world. Two parameters, mean nocturnal baseline impedance (MNBI) and post-reflux swallow-induced peristaltic wave index (PSPW), have been recently proposed to help differentiate GERD phenotypes. Our study aimed to assess whether there is any correlation between the two parameters, while also taking a look at their ability to distinguish between GERD phenotypes. We recruited 81 patients who were divided into 4 groups based on their GERD phenotype: erosive reflux disease (ERD), non-erosive reflux disease (NERD), reflux hypersensitivity (RH), and functional heartburn (FH). Both MNBI (AUROC 0.855) and PSPW (AUROC 0.835) had very good performances in separating ERD patients from non-ERD patients. PSPW (AUROC 0.784) was superior to MNBI (AUROC 0.703) in distinguishing NERD patients from patients with RH or FH. The PSPW index (AUROC 0.762) was more effective than MNBI (AUROC 0.668) in separating RH from FH. We found that PSPW and MNBI have a strong statistical correlation (Pearson correlation coefficient, r = 0.722, p < 0.001). Furthermore, PSPW predicted pathological MNBI (<2292 Ω) with good performance (AUROC 0.807). MNBI and PSPW are useful in distinguishing GERD phenotypes, with a strong correlation between the two parameters.

Poliprotect vs Omeprazole in the Relief of Heartburn, Epigastric Pain, and Burning in Patients Without Erosive Esophagitis and Gastroduodenal Lesions: A Randomized, Controlled Trial

INTRODUCTION

In the treatment of upper GI endoscopy-negative patients with heartburn and epigastric pain or burning, antacids, antireflux agents, and mucosal protective agents are widely used, alone or as add-on treatment, to increase response to proton-pump inhibitors, which are not indicated in infancy and pregnancy and account for significant cost expenditure.

METHODS

In this randomized, controlled, double-blind, double-dummy, multicenter trial assessing the efficacy and safety of mucosal protective agent Poliprotect (neoBianacid, Sansepolcro, Italy) vs omeprazole in the relief of heartburn and epigastric pain/burning, 275 endoscopy-negative outpatients were given a 4-week treatment with omeprazole (20 mg q.d.) or Poliprotect (5 times a day for the initial 2 weeks and on demand thereafter), followed by an open-label 4-week treatment period with Poliprotect on-demand. Gut microbiota change was assessed.

RESULTS

A 2-week treatment with Poliprotect proved noninferior to omeprazole for symptom relief (between-group difference in the change in visual analog scale symptom score: [mean, 95% confidence interval] -5.4, -9.9 to -0.1; -6.2, -10.8 to -1.6; intention-to-treat and per-protocol populations, respectively). Poliprotect's benefit remained unaltered after shifting to on-demand intake, with no gut microbiota variation. The initial benefit of omeprazole was maintained against significantly higher use of rescue medicine sachets (mean, 95% confidence interval: Poliprotect 3.9, 2.8-5.0; omeprazole 8.2, 4.8-11.6) and associated with an increased abundance of oral cavity genera in the intestinal microbiota. No relevant adverse events were reported in either treatment arm.

DISCUSSION

Poliprotect proved noninferior to standard-dose omeprazole in symptomatic patients with heartburn/epigastric burning without erosive esophagitis and gastroduodenal lesions. Gut microbiota was not affected by Poliprotect treatment. The study is registered in Clinicaltrial.gov (NCT03238534) and the EudraCT database (2015-005216-15).

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.

The clinical application value of salivary pepsin in the diagnosis of gastroesophageal reflux diseases

BACKGROUND

Peptest is a noninvasive and convenient diagnostic kit for gastroesophageal reflux disease (GERD). We aimed to explore the application value of Peptest in the diagnosis of GERD.

METHODS

Patients suspected of GERD all completed 24 h pH-impedance monitoring (24 h MII-pH) and then took proton pump inhibitor (PPI) 2 weeks. The postprandial, post-symptom and random salivary samples were taken. Receiver operating characteristic analysis was used to identify the best cutoff value of Peptest, to differentiate GERD patients from non-GERD patients and the optimal sampling time of Peptest was analyzed. Reflux characteristics and esophageal motility between Peptest (+) group and Peptest (-) group were compared in negative 24 h MII-pH patients. Peptest concentration were compared among non-reflux, distal reflux, and proximal reflux groups according to 24 h MII-pH curve.

RESULTS

The area under the curve of post-symptom Peptest was highest in three time points and the diagnostic specificity was 81.0% and sensitivity was 53.3% with the diagnostic value of 86 ng/mL. Compared with negative Peptest group, distal mean nocturnal baseline impedance was significantly lower, gastroesophageal junction contractile integral was substantially lower in positive Peptest group in negative 24 h MII-pH patients. The concentration of post-symptom and postprandial Peptest increased gradually in the non-reflux, distal reflux, and proximal reflux groups.

CONCLUSIONS & INFERENCES

Peptest has a relatively low diagnostic value for GERD. Post-symptom Peptset is the best sampling time with the optimal value of 86 ng/mL and may have auxiliary diagnostic value for negative 24 h MII-pH patients. Peptest may assist 24 h MII-pH in monitoring proximal reflux.

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.

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.

Novel Diagnostic Techniques in the Evaluation of Gastroesophageal Reflux Disease (GERD)

In our present clinical paradigm, patient symptoms and presentation in the setting of traditional findings from endoscopy (erosive esophagitis, Barrett's esophagus, reflux-mediated stenosis), esophageal high-resolution manometry, and/or ambulatory reflux monitoring (distal esophageal acid exposure time, numbers of reflux events, reflux-symptom association) guide the care of patients with suspected GERD. However, novel metrics and techniques acquired from or performed at endoscopy, manometry, or pH-impedance monitoring, beyond conventional evaluation, are of great interest to the gastroenterology community given the frequent (and sometimes challenging) presentation of suspected GERD. These novel and evolving diagnostic approaches have the potential to enhance the evaluation of these patients and optimize their management. In this invited review, we discuss the present evidence and potential clinical utility of selected GERD metrics and techniques of interest at endoscopy (dilated intercellular spaces, mucosal impedance), manometry (contractile integral, impedance analysis, straight leg raise, multiple rapid swallow maneuvers), and reflux monitoring (mean nocturnal baseline impedance, post-reflux swallow-induced peristaltic wave indices), and how these tools may be most optimally adopted and utilized for clinical care (Fig. 1).

Esophageal chemical clearance and mucosa integrity values in refractory gastroesophageal reflux disease patients with different esophageal dynamics

OBJECTIVES

Esophageal post-reflux swallow-induced peristaltic wave index (PSPWI) and mean nocturnal baseline impedance (MNBI), novel impedance-based markers of reflux burden, are associated with esophageal dynamics. We aim to investigate the characteristics of PSPWI and MNBI in Chinese refractory gastroesophageal reflux disease (RGERD) patients with different esophageal dynamic changes.

MATERIALS AND METHODS

201 RGERD and 76 functional heartburn patients, undergone off-PPI endoscopy, esophageal manometry and impedance-pH monitoring, were included. Comparisons of conventional and novel impedance-pH metrics were made among different esophageal dynamics groups. Receiver operating-characteristic analyses were utilized to evaluate the diagnostic efficacy of PSPWI and MNBI in differentiating abnormal esophageal dynamics. Correlations were used to investigate their associated factors.

RESULTS

PSPWI and MNBI of RGERD with esophagogastric junction (EGJ) injury and esophageal dysmotility were lower than EGJ injury alone or normal dynamics (p < 0.05 for both comparisons). PSPWI with esophageal peristalsis abnormality was lower than EGJ injury (p = 0.049), while MNBI showed no statistical difference. PSPWI, MNBI and their combination have auxiliary diagnostic values for esophageal peristalsis [area under the curves (AUCs): 0.683, 0.656, 0.708)] while only their combination for EGJ injury (AUC: 0.610). And they positively correlated with esophageal motility while negatively correlated with ineffective swallows and acid reflux events.

CONCLUSIONS

PSPWI and MNBI, indicating impairment of esophageal chemical clearance and mucosa integrity, were lower in RGERD patients with multiple esophageal dynamic injuries than single injuries or normal dynamics. Moreover, they provided useful contributing information for potential dynamic injuries if manometry has already been found normal or marginal.

Application of Artificial Intelligence in Measuring Novel pH-Impedance Metrics for Optimal Diagnosis of GERD

Novel metrics extracted from pH-impedance monitoring can augment the diagnosis of gastroesophageal reflux disease (GERD). Artificial intelligence (AI) is being widely used to improve the diagnostic capabilities of various diseases. In this review, we update the current literature regarding applications of artificial intelligence in measuring novel pH-impedance metrics. AI demonstrates high performance in the measurement of impedance metrics, including numbers of reflux episodes and post-reflux swallow-induced peristaltic wave index and, furthermore, extracts baseline impedance from the entire pH-impedance study. AI is expected to play a reliable role in facilitating measuring novel impedance metrics in patients with GERD in the near future.

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.

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.

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.

Diagnostics of Gastrointestinal Motility and Function: Update for Clinicians

Disorders of gastrointestinal (GI) tract motility and function are prevalent in the general population and negatively affect quality of life [...]

Mean Nocturnal Baseline Impedance and Post-reflux Swallow-induced Peristaltic Wave Index Could Identify Gastroesophageal Reflux Disease but pH-Impedance Metrics Alone Might Not Correlate With Proton Pump Inhibitor Response in Chinese Patients With Typical Reflux Symptoms

Background/Aims

Lyon consensus differentiates acid exposure time (AET) as physiological, borderline, and pathological. Mean nocturnal baseline impedance (MNBI) and post-reflux swallow-induced peristaltic wave index (PSPWi) are believed to increase diagnostic yield of gastroesophageal reflux disease (GERD) and correlate with symptom outcome of proton pump inhibitor (PPI) treatment. We aim to explore the clinical characteristics and the correlation of pH-impedance parameters with PPI response in Chinese patients with different AET levels.

Methods

We retrospectively investigated 177 patients with typical reflux symptoms who received esophageal function tests. The demographics, GERD questionnaire scores, the proportion of esophagitis and PPI responders, and manometric and pH-impedance parameters were compared among patients with AET < 4%, 4-6%, and > 6%. In patients with AET ≥ 4%, manometric and pH-impedance parameters were compared between PPI responders and non-responders.

Results

Among 177 patients, 69 (39.0%) had AET 4-6%, and 53 (29.9%) had AET > 6%. The demographics, esophagogastric junction type, and occurrence of ineffective esophageal motility were similar between patients with AET 4-6% and > 6%, but different from AET < 4%. MNBI and PSPWi were different among different AET levels, but similar between PPI responders and non-responders in patients with AET ≥ 4%.

Conclusions

It is reasonable to set 4% as a threshold to define pathological AET in Chinese patients. MNBI and PSPWi could identify GERD patients, but may not correlate with PPI response of Chinese GERD patients.

The Lyon Consensus Criteria for GERD Diagnosis in a Greek Population: The Clinical Impact and Changes in GERD Diagnosis in a Real-World, Retrospective Study

(1) Introduction/aim: Gastroesophageal reflux disease (GERD) affects 8−33% globally. The gold standard examination technique in diagnosing GERD is 24 h pHmetry ± impedance. Recently, new diagnostic criteria were introduced by the Lyon Consensus for GERD diagnosis. Our aim was to investigate the diagnostic yield of pHmetry + impedance using the Lyon Consensus criteria in a real-world study. (2) Patients and methods: Our study included 249 consecutive patients (M/F: 120/129, mean age 50 ± 15 years) who underwent 24 h pH+ impedance monitoring in our department, during a 5-year period. Epidemiological, endoscopic, clinical, and 24 h pH+ impedance data were retrospectively collected. (3) Results: Typical GERD symptoms were reported by 140/249 (56.2%) patients, whereas 99/249 (39.6%) patients reported various extraesophageal symptoms. Endoscopic findings supportive of GERD based on the Lyon Consensus were present in 42/185 (22.7%). An AET value of >6% was observed in 60/249 (24.1%). GERD diagnosis according to the Lyon Consensus criteria was set in 63/249 (25.3%) patients; a rate significantly lower than that observed by implementing the older criteria (32.1%), p < 0.001. In the multivariate analysis, the existence of endoscopic findings supportive of GERD diagnosis as defined by the Lyon Consensus (p = 0.036), a De Meester score of over 14.7, and the presence of typical GERD symptoms were correlated to GERD diagnosis (p < 0.001, respectively) using the criteria defined for pH−impedance monitoring. (4) Conclusions: Changes in the diagnostic criteria concerning the 24 h pH−impedance monitoring of GERD based on the Lyon Consensus led to a conclusive GERD diagnosis in approximately 25% of the patients. This rate of GERD diagnosis is reduced in comparison to the one confirmed with the use of previously established criteria.

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.

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.

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.