Determinants of reflux-induced chronic cough

Positive effect of deep diaphragmatic breathing training on gastroesophageal reflux-induced chronic cough: a clinical randomized controlled study

BACKGROUND AND OBJECTIVE

To explore the efficacy of deep diaphragmatic breathing training (DEP) in patients with gastroesophageal reflux-induced chronic cough (GERC).

METHODS

A randomized controlled study was conducted involving 60 GERC patients who were divided into the intervention group and the control group (each with 30 patients). Both groups received routine medication treatment for GERC, while the intervention group received DEP training additionally. Both groups were evaluated by cough symptom scores, Hull airway reflux questionnaire (HARQ), gastroesophageal reflux diagnostic questionnaire (GerdQ), generalized anxiety disorder scale-7 (GAD-7), patient health questionnaire-9 (PHQ-9), Pittsburgh sleep quality index (PSQI), the Leicester cough questionnaire (LCQ), as well as capsaicin cough sensitivity testing, B-ultrasound and surface electromyography (sEMG) of the diaphragmatic muscles before and after treatment. The cough resolution rate and changes of the above indictors was compared between the two groups after eight weeks of treatment.

RESULTS

After eight weeks of treatment, cough symptoms improved in both groups, but the cough resolution rate in the intervention group of 94% was significantly higher than that in the control group of 77% (χ2 = 6.402, P = 0.041). The intervention group showed significant improvements to the control group in GerdQ (6.13(0.35) VS 6.57(0.77)), GAD-7 (0(0;1) VS 1(0;3)), PSQI (2(1;3) VS 4(3;6)), LCQ (17.19(1.56) VS 15.88(1.92)) and PHQ-9 (0(0;0) VS 0(0;3)) after treatment. Compared to control group, sEMG activity of the diaphragmatic muscle was significantly increased in the intervention group after treatment, measured during DEP (79.00(2.49) VS 74.65 (1.93)) and quiet breathing (72.73 (1.96) VS 67.15 (2.48)).

CONCLUSION

DEP training can improve cough symptoms as an adjunctive treatment in GERC patients.

TRIAL REGISTRATION

The protocol was registered in February 2, 2022 via the Chinese Clinical Trials Register ( http://www.chictr.org.cn/ ) [ChiCTR2200056246].

Superficial oesophageal mucosal innervation may contribute to severity of symptoms in oesophageal motility disorders

BACKGROUND

Mechanisms underlying perception of dysphagia and chest pain have not been completely elucidated, although oesophageal mucosal afferent nerves might play an important role.

AIMS

To evaluate the relationship between oesophageal mucosal afferent nerves and the severity of dysphagia and chest pain in oesophageal motility disorders.

METHODS

We prospectively recruited patients with oesophageal motility disorders having dysphagia and/or chest pain from whom oesophageal biopsies were obtained. High-resolution manometry classified patients into disorders of oesophagogastric junction (OGJ) outflow and disorders of peristalsis. Symptom severity was assessed using validated questionnaires including Brief Oesophageal Dysphagia Questionnaire (BEDQ). Immunohistochemistry was performed on oesophageal biopsies to evaluate the location of calcitonin gene-related peptide (CGRP)-immunoreactive mucosal afferent nerves. Findings were compared to existing data from 10 asymptomatic healthy volunteers.

RESULTS

Of 79 patients, 61 patients had disorders of OGJ outflow and 18 had disorders of peristalsis. CGRP-immunoreactive mucosal nerves were more superficially located in the mucosa of patients with oesophageal motility disorders compared to healthy volunteers. Within disorders of OGJ outflow, the location of CGRP-immunoreactive nerves negatively correlated with BEDQ score both in the proximal (ρ = -0.567, p < 0.001) and distal oesophagus (ρ = -0.396, p = 0.003). In the proximal oesophagus, strong chest pain was associated with more superficially located mucosal nerves than weak chest pain (p = 0.04). Multivariate analysis showed superficial nerves in the proximal oesophagus was independently associated with severe dysphagia in disorders of OGJ outflow (p = 0.008).

CONCLUSIONS

Superficial location of mucosal nerves in the proximal oesophagus might contribute to symptoms, especially severe dysphagia, in disorders of OGJ outflow.

Relationship between depression severity and respiratory symptoms in US adults: A national cross-sectional study

OBJECTIVE

The relationship between depression severity and cough, wheeze and exertional dyspnoea is unclear. The aim of this study was to explore this relationship.

METHODS

We used weighted logistic regression analysis and fitted curves to explore the relationship between depression severity and respiratory symptoms. In addition, we examined the relationship between depression and COPD and asthma. Stratified analyses were used to analyse specific populations.

RESULTS

We weighted 10,142 subjects to reflect the entire US population. Using the population without depression as a reference, the risk of cough and asthma in the severely depressed population was 3.32 times (OR 3.324, 95% CI 1.567-7.050) and 2.84 times (OR 2.842, 95% CI 1.521-5.311) higher than that in the population without depressive symptoms, and the risk of asthma and COPD was 2.4 times and 2.6 times (OR 2.410, 95% CI 1.371-4.236; OR 2.566, 95% CI 1.236-4.921). In subgroup analyses, the correlation between depression scores and prevalence of cough and wheeze was corrected for gender level. In addition, smoking status and marital status were interaction factors between depression score and prevalence of cough. The prevalence of exertional dyspnoea by depression score was influenced by CVD.

CONCLUSIONS

Depression severity was associated with respiratory symptoms, asthma, and COPD. Gender corrected the correlation between depression and cough and asthma, and depressive state was an independent risk factor for asthma and COPD. This finding provides new ideas for the management of respiratory symptoms and diseases.

Gabapentin alleviated the cough hypersensitivity and neurogenic inflammation in a guinea pig model with repeated intra-esophageal acid perfusion

OBJECTIVE

The anti-tussive effect of gabapentin and its underlying neuromodulatory mechanism were investigated via a modified guinea pig model of gastroesophageal reflux-related cough (GERC).

METHODS

Intra-esophageal perfusion with hydrochloric acid (HCl) was performed every other day 12 times to establish the GERC model. High-dose gabapentin (48 mg/kg), low-dose gabapentin (8 mg/kg), or saline was orally administered for 2 weeks after modeling. Cough sensitivity, airway inflammation, lung and esophagus histology, levels of substance P (SP), and neurokinin-1 (NK1)-receptors were monitored.

RESULTS

Repeated intra-esophageal acid perfusion aggravated the cough sensitivity in guinea pigs in a time-dependent manner. The number of cough events was significantly increased after 12 times HCl perfusion, and the hypersensitivity period was maintained for 2 weeks. The SP levels in BALF, trachea, lung, distal esophagus, and vagal ganglia were increased in guinea pigs receiving HCl perfusion. The intensity of cough hypersensitivity in the GERC model was significantly correlated with increased SP expression in the airways. Both high and low doses of gabapentin administration could reduce cough hypersensitivity exposed to HCl perfusion, attenuate airway inflammatory damage, and inhibit neurogenic inflammation by reducing SP expression from the airway and vagal ganglia.

CONCLUSIONS

Gabapentin can desensitize the cough sensitivity in the GERC model of guinea pig. The anti-tussive effect is associated with the alleviated peripheral neurogenic inflammation as reflected in the decreased level of SP.

Characteristics of Laryngopharyngeal Reflux in Patients with Chronic Cough Induced by Gastroesophageal Reflux Disease

Objective: To summarize the characteristics of laryngopharyngeal reflux in patients with chronic cough induced by gastroesophageal reflux disease (GERD). Materials and Methods: The clinical data of patients with chronic cough induced by GERD treated at our hospital were retrospectively analyzed, including their reflux symptom index (RSI), reflux finding scores (RFS), and results of oropharyngeal pH monitoring. Results: There were 44 patients in total, including 21 males and 23 females. The average history of chronic cough was 29.60 (29.60 ± 37.60) months. In addition to coughing, all patients had at least 2 symptoms of laryngopharyngeal reflux disease (LPRD), and their RSI averaged 15.66 (15.66 ± 6.33). The most frequent symptoms were cough, throat clearing, excessive phlegm, or postnasal drip. All patients had LPRD signs, with an average RFS of 10.89 (10.89 ± 2.81). The most frequent signs were erythema or hyperemia/vocal cord edema, posterior commissure hypertrophy, and diffuse laryngeal edema. There were 42 patients (42/44, 95.45%) whose RSI and/or RFS were abnormal. Oropharyngeal pH monitoring identified 10 patients (10/44, 22.72%) with abnormal Ryan scores. Conclusions: All patients with chronic cough induced by GERD had symptoms and signs of LPRD, and most of them had an abnormal RSI and/or RFS and could be diagnosed with suspect LPRD. A part of the patients had LPR episodes according to Dx-pH monitoring, most of which occurred in the upright position. These results indicated that most patients with chronic cough induced by GERD may have suspected LPRD simultaneously and that cough was one of their LPRD symptoms.

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.

GERD-related chronic cough: Possible mechanism, diagnosis and treatment

GERD, or gastroesophageal reflux disease, is a prevalent medical condition that affects millions of individuals throughout the world. Chronic cough is often caused by GERD, and chronic cough caused by GER is defined as GERD-related chronic cough (GERC). It is still unclear what the underlying molecular mechanism behind GERC is. Reflux theory, reflex theory, airway allergies, and the novel mechanism of esophageal motility disorders are all assumed to be linked to GERC. Multichannel intraluminal impedance combined with pH monitoring remains the gold standard for the diagnosis of GERC, but is not well tolerated by patients due to its invasive nature. Recent discoveries of new impedance markers and new techniques (mucosal impedance testing, salivary pepsin, real-time MRI and narrow band imaging) show promises in the diagnosis of GERD, but the role in GERC needs further investigation. Advances in pharmacological treatment include potassium-competitive acid blockers and neuromodulators (such as Baclofen and Gabapentin), prokinetics and herbal medicines, as well as non-pharmacological treatments (such as lifestyle changes and respiratory exercises). More options have been provided for the treatment of GERC other than acid suppression therapy and anti-reflux surgery. In this review, we attempt to review recent advances in GERC mechanism, diagnosis, and subsequent treatment options, so as to provide guidance for management of GERC.

Investigating the diagnostic utility of high-resolution oesophageal manometry in patients with refractory respiratory symptoms

BACKGROUND

The interaction between the respiratory and gastrointestinal systems, and the role of the latter in the development of respiratory pathology, has been examined with a focus on gastro-oesophageal reflux disease (GORD). However, little data exists examining the link between oesophageal motility and respiratory disease.

AIMS AND OBJECTIVES

In this study, we examined patterns in oesophageal motility using high-resolution oesophageal manometry (HROM) in patients with refractory respiratory symptoms.

METHODS

Data were collected retrospectively for all patients that were investigated using HROM at a single centre for refractory respiratory symptoms between January 1st, 2011-December 1st, 2021. Patients were selected for investigation based on airway reflux symptoms, measured by the Hull Airways Reflux Questionnaire (HARQ).

RESULTS

441 patients were investigated with HROM (64% female, mean age = 56.5 [SD = 13.9]). The commonest diagnoses of these patients were Chronic Cough (77%, n = 339), Asthma (10%, n = 44), and Interstitial Lung Disease (7%, n = 29). The prevalence of oesophageal dysmotility was 66% in our cohort. Those with oesophageal dysmotility had significantly higher HARQ scores than those with normal motility (40.6 vs 35.3, p < 0.001) and there was a significant inverse correlation between HARQ scores and distal contractile integral (DCI), a measure of oesophageal contractility.

CONCLUSIONS

Two-thirds of patients with refractory respiratory symptoms were found to have oesophageal dysmotility on HROM. These findings suggest motility disorders of the oesophagus may contribute to the development and progression of respiratory disease. This study highlights the need for further prospective study of the relationship between oesophageal dysmotility and respiratory disease.

Diagnostic value of reflux episodes in gastroesophageal reflux-induced chronic cough: a novel predictive indicator

Background

Multichannel intraluminal impedance and pH-monitoring (MII-pH) is an essential testing modality for gastroesophageal reflux-induced chronic cough (GERC), while the existing diagnostic criteria still have some inherent defects. This study aimed to explore the diagnostic value of a direct and objective index, reflux episodes, and related parameters in MII-pH in different types of GERC.

Methods

Patients with chronic cough suspected of gastroesophageal reflux disease who successfully received MII-pH were enrolled. The differences in MII-pH parameters were analyzed among patients with different etiologies and the predictive diagnostic value of reflux episodes and related parameters were analyzed in patients with GERC, acid GERC, and non-acid GERC, and compared with existing diagnostic criteria.

Results

A total of 190 patients with suspected GERC who underwent MII-pH were enrolled; 131 of these patients were finally diagnosed with GERC. When the reflux episodes were used to diagnose GERC, the area under the curve (AUC) was 0.684; when the acid reflux episodes and the ratio of acid reflux episodes were used to diagnose acid GERC, the AUCs were 0.769 and 0.854; when the non-acid reflux episodes and the ratio of non-acid reflux episodes were used to diagnose non-acid GERC, the AUCs were 0.735 and 0.705, respectively. When the non-acid reflux episodes > 58 and the proportion of non-acid reflux episodes > 68.18% were used alone or in combination to diagnose non-acid GERC, their diagnostic value was significantly better than SAP or SI (all ps < 0.05).

Conclusion

The number of reflux episodes has a good diagnostic value for GERC, especially in the diagnosis of non-acid GERC.

Novel Advanced Impedance Metrics on Impedance-pH Testing Predict Lung Function Decline in Idiopathic Pulmonary Fibrosis

INTRODUCTION

Gastroesophageal reflux has been associated with idiopathic pulmonary fibrosis (IPF). Mean nocturnal baseline impedance (MNBI) is a marker of esophageal mucosal integrity, whereas postreflux swallow-induced peristaltic wave (PSPW) index reflects esophageal chemical clearance. Both metrics offer novel ways to assess reflux burden on multichannel intraluminal impedance-pH testing (MII-pH), but their role in extraesophageal reflux remains unclear. We aimed to evaluate the relationship between these novel metrics and lung function decline in patients with IPF.

METHODS

Adults with IPF undergoing prelung transplant MII-pH were enrolled. All patients completed pulmonary function testing (PFT) at the time of MII-pH and at the 1-year follow-up. MNBI was calculated by averaging baseline impedance at three 10-minute intervals (1 AM/2 AM/3 AM). PSPW index was the proportion of all reflux episodes, followed by a peristaltic swallow within 30 seconds. Univariate (Student t-test/Pearson correlation) and multivariable (general linear regression) analyses were performed.

RESULTS

One hundred twenty-five subjects (mean age = 61.7 years, 62% men) were included. Forced expiratory volume in one second and forced vital capacity declined more significantly over 12 months in subjects with lower distal MNBI, proximal MNBI, and PSPW index (all P < 0.05). On multivariable analyses adjusting for age, sex, proton pump inhibitor use, and baseline lung function, distal MNBI (β = -10.86, P = 0.024; β = -8.03, P = 0.045), proximal MNBI (β = -13.5, P = 0.0068; β = -9.80, P = 0.025), and PSPW index (β = -18.1, P = 0.010; β = -12.55, P = 0.050) remained predictive of greater forced expiratory volume in one second and forced vital capacity decline.

DISCUSSION

Low distal MNBI, proximal MNBI, and PSPW index independently predicted more severe lung function decline over 1 year in patients with IPF. These impedance metrics may have prognostic value and support a role for reflux in IPF pathogenesis.

Limited Clinical Utility of Lipid-Laden Macrophage Index of Induced Sputum in Predicting Gastroesophageal Reflux-Related Cough

Gastroesophageal reflux disease (GERD) is a common cause of chronic cough (CC). However, the diagnosis of GERD associated with CC based on 24-hour esophageal pH-monitoring or favorable response to empirical anti-reflux trials is invasive and time-consuming. Lipid-laden macrophages (LLMs) are supposed to be a biomarker for micro-aspiration of gastric content in the respiratory tract. This study was conducted to collect LLMs by the sputum induction technique and observe the relationship among the amount of LLMs, cough severity, parameters of 24-hour esophageal pH-monitoring and therapeutic response. The 24-hour esophageal pH-monitoring and sputum induction were performed on 57 patients with suspected GERD associated with CC. Thirty-four patients were followed up after empirical anti-reflux trials of 8 weeks to record the therapeutic response. Lipid-laden macrophage index (LLMI), a semiquantitative counting of LLMs, showed no significant correlation with the values of 24-hour esophageal pH monitoring at the proximal or remote electrode. No difference in LLMI or DeMeester score, as well as cough symptom association probability, were found between the responders and the non-responders. Reflux symptoms were more common in the responders (50%) compared to the non-responders (6%) (P < 0.05). Our study suggests that LLMI shows limited utility in clinically diagnosing GERD associated with CC as an underlying etiology or in predicting response to anti-reflux therapy. Anti-reflux therapy is more effective for CC patients with reflux symptoms than for those without.

Gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease (GERD) is a common disorder in adults and children. The global prevalence of GERD is high and increasing. Non-erosive reflux disease is the most common phenotype of GERD. Heartburn and regurgitation are considered classic symptoms but GERD may present with various atypical and extra-oesophageal manifestations. The pathophysiology of GERD is multifactorial and different mechanisms may result in GERD symptoms, including gastric composition and motility, anti-reflux barrier, refluxate characteristics, clearance mechanisms, mucosal integrity and symptom perception. In clinical practice, the diagnosis of GERD is commonly established on the basis of response to anti-reflux treatment; however, a more accurate diagnosis requires testing that includes upper gastrointestinal tract endoscopy and reflux monitoring. New techniques and new reflux testing parameters help to better phenotype the condition. In children, the diagnosis of GERD is primarily based on history and physical examination and treatment vary with age. Treatment in adults includes a combination of lifestyle modifications with pharmacological, endoscopic or surgical intervention. In refractory GERD, optimization of proton-pump inhibitor treatment should be attempted before a series of diagnostic tests to assess the patient's phenotype.

Metabolomic profiling of extraesophageal reflux disease in children

Although respiratory symptoms in children are often attributed to gastroesophageal reflux disease, establishing a clear diagnosis of extraesophageal reflux disease (EERD) can be challenging, as there are no sensitive or specific EERD biomarkers. The aim of this study was to evaluate the metabolite profile in bronchoalveolar (BAL) fluid from children with suspected EERD and assess the impact of reflux treatment on these metabolites. In this prospective pilot study, we performed nontargeted global metabolomic profiling on BAL fluid from 43 children undergoing testing with bronchoscopy, upper endoscopy, and multichannel intraluminal impedance with pH (pH-MII) for evaluation of chronic respiratory symptoms. Twenty-three (54%) patients had an abnormal pH-MII study. Seventeen (40%) patients were on proton pump inhibitors (PPIs) for testing. Levels of histamine, malate, adenosine 5'-monophosphate, and ascorbate were significantly lower in subjects with abnormal pH-MII studies compared to those normal studies. Furthermore, in children off PPI therapy, those with abnormal pH-MII studies had robust increases in a number of glycerophospholipids within phospholipid metabolic pathways, including derivatives of glycerophosphorylcholine, glycerophosphoglycerol, and glycerophosphoinositol, compared to those with normal pH-MII studies. These findings offer insight into the impact of reflux and PPIs on the lungs and provide a foundation for future studies using targeted metabolomic analysis to identify potential biomarkers of EERD.

Gastroesophageal reflux and asthma: when, how, and why

PURPOSE OF REVIEW

Gastro-esophageal reflux is a possible cause of uncontrolled symptoms of asthma and should be actively investigated and treated before severe asthma is diagnosed and biological therapy started.

RECENT FINDINGS

Recent investigations on esophageal function and tissue biomarkers in patients with asthma and associated GERD have established a relevant role for esophageal motility and neuronal sensory abnormalities in linking the two diseases. Characterization of the underpinning inflammatory substrate has showed mixed results as both neutrophilic and eosinophilic type 2 inflammatory changes have been described.

SUMMARY

New findings regarding inflammatory mechanisms in GERD-associated asthma as well as new diagnostic tools to investigate functional esophageal abnormalities and characterize asthma endotype have identified potential treatable traits that may improve the clinical management and outcome of asthmatic patients with GERD.

What is the truth about proton pump inhibitors?

PURPOSE OF REVIEW

This review explores the recent evidence and established scientific literature surrounding proton pump inhibitors in the context of laryngology.

RECENT FINDINGS

Proton pump inhibitors are often associated with gastroenterology; however, they also have a place in laryngology. Several laryngopharyngeal disorders are treated with proton pump inhibitors, though limited evidence regarding effectiveness, dosing and length of treatment exists. With the recent influx of articles reporting possible adverse effects of proton pump inhibitors, the appropriate prescribing of them has come under scrutiny. These reported risks include cancer, stroke, myocardial infarction, kidney disease and cognitive decline. It should be noted though that many of these studies by nature, are fraught with potential confounding. Regardless, clinicians ought to be aware of any risks associated with treatment regimens and prescribe the optimal dosage and duration.

SUMMARY

Proton pump inhibitor treatment should be dose-appropriate and for a limited duration. Concerning potential adverse effects, the limitations of retrospective cohort studies must be taken into consideration when reviewing the evidence.

The role of ambulatory 24-hour esophageal manometry in clinical practice

High-resolution manometry revolutionized the assessment of esophageal motility disorders and upgraded the classification through the Chicago Classification. A known disadvantage of standard HRM, however, is the inability to record esophageal motility function for an extended time interval; therefore, it represents only a more snapshot view of esophageal motor function. In contrast, ambulatory esophageal manometry measures esophageal motility over a prolonged period and detects motor activity during the entire circadian cycle. Furthermore, ambulatory manometry has the ability to measure temporal correlations between symptoms and motor events. This article aimed to review the clinical implications of ambulatory esophageal manometry for various symptoms, covering literature on the manometry catheter, interpretation of findings, and relevance in clinical practice specific to the evaluation of non-cardiac chest pain, chronic cough, and rumination syndrome.

Helicobacter pylori is associated with weakened pulmonary function and reduced incidence of allergic conditions in patients with chronic cough

The present study aimed to investigate the potential association between Helicobacter pylori (a H. pylori) positive state and chronic cough. A clinical observational study with systematic analysis was performed, including 278 patients with complaints of chronic cough and 148 healthy controls. a H. pylori positive state was present in 61.2% of the patients in the chronic cough group and 68.9% in the chronic refractory cough group, as opposed to 43.9% in the control group. There was a significant improvement in 65.5% of the patients with chronic refractory cough following successful a H. pylori eradication therapy. In addition, patients with chronic cough exposed to a H. pylori exhibited decreased pulmonary function with a decrease in forced expiratory volume in 1 sec by 84 ml, a decrease in the forced vital capacity by 53 ml and a decrease in maximal vital capacity by 46 ml. The difference was even more obvious in the chronic refractory cough group. The allergy status differed significantly according to age between a H. pylori-positive and -negative cases in the cough variant asthma and allergic cough groups. Among patients aged <40 years, a H. pylori-positive cases had a lower prevalence of atopy and lower total serum immunoglobin E levels compared with a H. pylori-negative cases. However, there was no significant association between a H. pylori status and C-reactive protein levels, erythrocyte sedimentation rate or eosinophil count in the peripheral blood. In conclusion, the present study demonstrated that a H. pylori infection may be a factor associated with chronic cough and it may be associated with a decline in pulmonary function and reduced incidence of allergic conditions. Thus, a H. pylori may represent a target for the treatment of chronic cough.

A SIGE-SINGEM-AIGO technical review on the clinical use of esophageal reflux monitoring

Patients with esophageal symptoms potentially associated with gastroesophageal reflux disease such as heartburn, regurgitation, chest pain, or cough represent one of the most frequent reasons for referral to gastroenterological evaluation. The utility of esophageal reflux monitoring in clinical practice is: (1) to accurately define reflux burden, (2) to segregate patients according to reflux monitoring results as true GERD, reflux hypersensitivity and functional heartburn, and (3) to establish a treatment plan. With this in mind, in the last decade, investigations and technical advances, with the introduction of impedance-pH monitoring and wireless pH capsule, have enhanced our understanding and management of GERD. The following recommendations were discussed and approved after a comprehensive review of the medical literature pertaining to reflux testing techniques and their recent application. This review created under the auspices of the Società Italiana di Gastroenterologia ed Endoscopia Digestiva (SIGE), Società Italiana di Neuro-Gastro-Enterologia e Motilità (SINGEM) and Associazione Italiana Gastroenterologi ed Endoscopisti Digestivi Ospedalieri (AIGO) is intended to help clinicians in applying reflux studies in the most fruitful manner within the context of their patients with esophageal symptoms.

Perspectives on chronic cough in Korea

Chronic cough is a common condition, and generally affects about 3% of Korean adults with a significant influence on quality of life (QoL). Despite continued clinical and academic efforts, there are unmet needs for chronic cough prevention and management in Korea. Epidemiologically, there are two major challenges: an aging population and air pollution. Korea is one of the most rapidly aging countries, and the relative proportion of elderly to younger people is expected to double within the next two decades. Air pollution is a major concern, but there is very limited evidence on the effects of air pollutant on cough in Korean patients. Clinically, upper and lower airway diseases, such as rhinitis/rhinosinusitis and cough variant asthma/eosinophilic bronchitis, are reported to account for about 75% of chronic cough in Korean adults, which formed the basis in formulating clinical practice guidelines. However, further studies are warranted to resolve clinical uncertainty, particularly for the evaluation and treatment of upper airway conditions in chronic cough. The prevalence of gastroesophageal reflux disease (GERD) is increasing, thus its relevance to cough among Koreans may warrant re-evaluation. Infection-associated chronic cough, such as tuberculosis, is another continuing concern. The proportion of chronic refractory or unexplained cough is assumed to be 10–20% among patients visiting referral clinics for chronic cough. This review presents our perspectives on current epidemiological and clinical issues of chronic cough in Korea, and addresses major knowledge gaps and future research priorities.

Extraesophageal syndrome of gastroesophageal reflux: relationships with lung disease and transplantation outcome

Gastroesophageal reflux disease (GERD) is prevalent and may be associated with both esophageal and extraesophageal syndromes, which include various pulmonary conditions. GERD may lead to pulmonary complications through the "reflux" (aspiration) or "reflex" (refluxate-triggered, vagally mediated airway spasm) mechanisms. While GERD may cause or worsen pulmonary disorders, changes in respiratory mechanics due to lung disease may also increase reflux. Typical esophageal symptoms are frequently absent and objective assessment with reflux monitoring is often needed for diagnosis. Impedance monitoring should be considered in addition to traditional pH study due to the involvement of both acidic and weakly acidic/nonacidic reflux. Antireflux therapy may improve outcomes of some pulmonary complications of GERD, although careful selection of a candidate is paramount to successful outcomes. Further research is needed to identify the optimal testing strategy and patient phenotypes that would benefit from antireflux therapy to improve pulmonary outcomes.

Symptomatic response to GERDOFF® in patients with gastro-esophageal reflux disease and poor response to alginates: an exploratory, post-market, open-label study

BACKGROUND/AIMS

A novel medical device based on hyaluronic acid, chondroitin sulphate plus aluminum hydroxide (GERDOFF®, melt-in-mouth tablets) showed efficacy in reducing GER-related symptoms. This exploratory, open-label study evaluated symptomatic effects of a 14-day treatment with GERDOFF® in GERD patients.

MATERIALS AND METHODS

GERD Impact Scale (GIS) questionnaire was filled at baseline visit, after 7 and 14 days of treatment; patients' Global Satisfaction was evaluated at the final visit. Primary endpoint was the reduction of heartburn episodes per week; secondary endpoints were GERD-related symptoms, patients' satisfaction, and safety.

RESULTS

Forty patients were included, 22 were on stable therapy with proton pump inhibitor (PPI). Compared to baseline, the days with heartburn episodes and the GIS score progressively decreased during the first (p<0.0001) and the second week of treatment (p<0.0001). Heartburn episodes per week (p<0.0001) and the GIS score (p<0.0001) decreased in the first and the last 7 days of 14-day treatment and did not differ between patients on and off PPI. The treatment was safe and well-tolerated, and it was rated as very good (46.2%) or good (43.6%) on the satisfaction questionnaire.

CONCLUSION

GERDOFF® could effectively treat GER symptoms in patients not responding to PPI or alginate-based formulation. ISRCTN_15143752.

Upper digestive tract abnormalities in dogs with chronic idiopathic lymphoplasmacytic rhinitis

BACKGROUND

Chronic idiopathic lymphoplasmacytic rhinitis (CILPR) is a common inflammatory disorder of unknown etiology affecting the nasal cavity of dogs. The diagnosis is made by exclusion of other causes of nasal disease and specific therapeutic protocols are lacking. In human medicine, a relationship between CILPR and gastrointestinal clinical signs has been postulated, and remission of respiratory signs after clinical trials with medications for gastrointestinal disorders has been observed.

OBJECTIVES

To describe history, clinical presentation, endoscopic and histopathologic concurrent respiratory and digestive tract abnormalities, and to evaluate improvement of respiratory signs after treatment for gastrointestinal signs.

ANIMALS

Twenty-five dogs with CILPR.

METHODS

Prospective study. For inclusion, following information had to be available: respiratory and digestive clinical signs, airway and digestive tract endoscopic abnormalities, histologic evaluation of respiratory and gastrointestinal tract biopsy specimens, and clinical response to different treatment strategies.

RESULTS

Twenty-two dogs had endoscopic gastrointestinal lesions, whereas 13 dogs had concurrent gastrointestinal signs. Most esophageal and duodenal endoscopic abnormalities were classified as moderate or severe. Respiratory and gastrointestinal tract histologic evaluation identified mostly chronic inflammation. Remission or marked improvement of respiratory signs was observed in the majority of dogs treated only for gastrointestinal signs up to 12 months after endoscopy. No significant associations between treatments and follow-up information were found.

CONCLUSION AND CLINICAL IMPORTANCE

Nasal and upper digestive tract abnormalities coexist in some dogs with CILPR. Lack of standardized therapeutic protocols suggests caution when interpreting improvement in nasal clinical signs. Additional studies are needed to explore the possibility of a cause-effect relationship between the 2 processes.

Recent progress in the management of chronic cough

Chronic cough is a common clinical condition with significant impact on quality of life and for which effective therapy remains an unmet clinical need. Over the past decade, there has been a major shift in how we approach this problem, driven by better appreciation of the clinical manifestation of chronic cough and an improved understanding of the associated neurobiology. "Cough hypersensitivity syndrome" has been proposed as a new diagnostic term for chronic cough, encompassing different phenotypes of the condition. Accumulating evidence suggests that this new concept is clinically relevant. However, while it is gaining widespread endorsement within the allergy and respiratory community, raising its profile in routine clinical practice is a priority. Thus, the present paper reviews recent progress in our understanding and management of chronic cough, with focus on mechanistic and clinical studies. It also provides detail on knowledge gaps and future research directions.

Impedance in the evaluation of the esophagus

The aim of this paper is to review esophageal electrical impedance technologies and to discuss the use of these technologies for physiological measurements, diagnostics, and therapy of esophageal disease. In order to develop a better understanding of the pathophysiology of and improve the diagnosis of esophageal disorders, such as gastroesophageal reflux disease (GERD) and achalasia, several new diagnostic tests, including intraluminal impedance, esophageal mucosal impedance, and the functional luminal imaging probe, have been developed. These technologies have proven valuable for assessment of the esophagus in recent years. They provide information on esophageal flow properties, mucosal integrity, lumen shape, and distensibility in esophageal disorders, in particular for GERD and achalasia. Despite their promise and novel clinical studies, the potential of these technologies has been far from realized. New multidisciplinary approaches will contribute to our understanding and interpretation of esophageal impedance data and disease mechanisms.

Persistence of chronic cough in a community-based population

Chronic cough causes significant impairment in the quality of life and is often immune to treatment. Previous studies about its persistence have focused on patients managed in special cough clinics. Little is known about the persistence of chronic cough in unselected populations. In this prospective follow-up study, we investigated factors that predict the persistence of cough at 12-month follow-up in a community-based study of subjects with chronic cough.

The first e-mail survey in 2017 included a questionnaire about current cough and its risk factors. The 264 subjects who reported chronic cough were sent a follow-up questionnaire 12 months later.

The response rate was 77.7% (205 subjects), of whom 165 subjects (80.5%) still had cough in 2018. In multivariate analysis, the following baseline factors predicted the persistence of cough at 12 months; gastro-oesophageal reflux disease (adjusted OR (aOR) 5.02 (95% CI 1.10–22.83)), presence of a chemical trigger (aOR 2.88 (95% CI (1.20–7.00)), duration of cough more than 1 year (aOR 2.80 (95% CI 1.27–6.22)), frequent somatic symptoms (aOR 1.31 (95% CI 1.07–1.59)), and low number of family members (aOR 0.71 (95% CI 0.52–0.98)).

In conclusion, most patients with chronic cough still suffer from cough 1 year later. The presence of gastro-oesophageal reflux disease is the main predictor for the persistence of cough.

Most patients with chronic cough still suffer from cough 1 year later. The presence of gastro-oesophageal reflux disease is the main predictor for the persistence of cough.http://bit.ly/2wMLPs1

Proximal reflux: biochemical mediators, markers, therapeutic targets, and clinical correlations

Airway reflux is implicated in the pathophysiology of a wide range of adult and pediatric upper and lower airway diseases. However, the diagnosis of proximal reflux-associated disease remains challenging due to evolving clinical criteria and institutional and regional variances in diagnostic practices. Evidence suggests that nonacidic contents of reflux may serve as both pathologic mediators of and biomarkers for reflux in the upper airway. Furthermore, they offer potential pharmaceutical and surgical intervention targets and are the focus of novel clinical diagnostic tools currently under investigation.

Laryngopharyngeal Reflux and Atypical Gastroesophageal Reflux Disease

Laryngopharyngeal reflux and atypical manifestations of gastroesophageal reflux disease have a high economic and social burden in the United States. There is increasing research supporting the reflex theory and hypersensitivity syndrome underlying this disease pathophysiology. Novel diagnostic biomarkers have gained more traction in the search for a more reliable diagnostic tool, but further research is needed. Current standard-of-care treatment relies on proton pump inhibitor therapy. Antireflux surgery is usually not recommended. Neuromodulators and treatments targeting specific neuronal receptors are discussed. A diagnostic algorithm is proposed for the evaluation of laryngeal symptoms suspected to be related to extraesophageal reflux disease.

Post-reflux swallow-induced peristaltic wave (PSPW): physiology, triggering factors and role in reflux clearance in healthy subjects

BACKGROUND AND AIMS

The underlying physiology of post-reflux swallow-induced peristaltic wave (PSPW) is unclear. We aimed to: 1) calculate the probability of a random association between reflux and PSPW; 2) characterize factors that could underlie triggering of PSPW and 3) assess the chemical clearance effect of PSPW in healthy asymptomatic subjects.

METHODS

A total of 251 impedance-pH tracings from healthy asymptomatic subjects were analysed. Twenty consecutive tracings from this pool with 20-40 reflux episodes/24 h and a PSPW index higher than 50% were separately analyzed to evaluate the probability of a random association between reflux and PSPW. The characteristics of reflux episodes followed by a PSPW were compared with those not associated with PSPW.

RESULTS

A mean time interval of 29.3 s between a reflux episode and the first swallow captured 71% of total reflux episodes, and 67% of accompanying swallows were non-random. Compared to reflux without PSPW, reflux episodes with PSPW were more frequently acidic (P = 0.048), mixed with gas (P < 0.0001), of high proximal extent (P < 0.0001), while awake (P < 0.0001), and with shorter chemical clearance time (P = 0.040). High proximal extent, gas presence and occurring while awake were independent factors associated with PSPW (P < 0.0001).

CONCLUSION

Using a time window between reflux and PSPW of around 30 s, the probability of a chance association is around 30%. Reflux episodes with high proximal extent, containing gas and occurring while awake are important factors associated with PSPW in healthy subjects. Reflux episodes with PSPW have a shorter chemical clearance time.

Gastroesophageal reflux disease and chronic cough: A possible mechanism elucidated by ambulatory pH-impedance-pressure monitoring

BACKGROUND

The pathophysiological mechanism(s) of gastroesophageal reflux disease (GERD)-related chronic cough (CC) is unclear. We aimed to determine the mechanism of reflux-induced cough by synchronous monitoring of reflux episodes, esophageal motility, and cough.

METHODS

Patients with GERD were prospectively enrolled and classified into GERD with CC (GERD-CC) and without CC (GERD) groups. Twenty-four-hour ambulatory pH-impedance-pressure monitoring was performed; the reflux patterns, esophageal motility during prolonged exposure to acid and characteristics of reflux episodes that induced coughing paroxysms were analyzed.

KEY RESULTS

Thirty-one patients with GERD-CC and 47 with GERD were enrolled; all of whose monitoring results fulfilled the criteria for diagnosis of GERD. Patients with GERD-CC had higher reflux symptom scores, longer exposure to acid, higher DeMeester scores, and more frequent reflux episodes, proximal extent reflux detected by impedance, and higher percentage of strongly acidic reflux than patients in the GERD group (all P < .05). Of 63 reflux-cough episodes identified in the GERD-CC group, 74.6% of distal reflux and 67.0% of proximal reflux episodes were acidic. More patients had low pan-esophageal pressure in primary peristalsis (48.5% vs 11.8%, P = .000) and synchronous contraction in secondary peristalsis during prolonged exposure to acid in the GERD-CC than in the GERD group (63.9% vs 9.1%, P = .000).

CONCLUSIONS & INFERENCES

Proximal acidic reflux and distal reflux-reflex are jointly associated with reflux-induced cough in patients with GERD. Low pan-esophageal pressure in primary peristalsis and synchronous contraction in secondary peristalsis may play important roles in GERD-associated chronic cough.

Extraesophageal Symptoms and Diseases Attributed to GERD: Where is the Pendulum Swinging Now?

The purpose of this review is to outline the recent developments in the field of extraesophageal reflux disease and provide clinically relevant recommendations. The recommendations outlined in this review are based on expert opinion and on relevant publications from PubMed and EMbase. The Clinical Practice Updates Committee of the American Gastroenterological Association proposes the following recommendations: Best Practice Advice 1: The role of a gastroenterologist in patients referred for evaluation of suspected extra esophageal symptom is to assess for gastroesophageal etiologies that could contribute to the presenting symptoms. Best Practice Advice 2: Non-GI evaluations by ENT, pulmonary and/or allergy are essential and often should be performed initially in most patients as the cause of the extraesophageal symptom is commonly multifactorial or not esophageal in origin. Best Practice Advice 3: Empiric therapy with aggressive acid suppression for 6-8 weeks with special focus on response of the extraesophageal symptoms can help in assessing association between reflux and extraesophageal symptoms. Best Practice Advice 4: No single testing methodology exists to definitively identify reflux as the etiology for the suspected extra esophageal symptoms. Best Practice Advice 5: Constellation of patient presentation, diagnostic test results and response to therapy should be employed in the determination of reflux as a possible etiology in extra esophageal symptoms. Best Practice Advice 6: Testing may need to be off or on proton pump inhibitor (PPI) therapy depending on patients' presenting demographics and symptoms in assessing the likelihood of abnormal gastroesophageal reflux. A. On therapy testing may be considered in those with high probability of baseline reflux (those with previous esophagitis, Barrett's esophagus or abnormal pH). B. Off therapy testing may be considered in those with low probability of baseline reflux with the goal of identifying moderate to severe reflux at baseline. Best Practice Advice 7: Lack of response to aggressive acid suppressive therapy combined with normal pH testing off therapy or impedance-pH testing on therapy significantly reduces the likelihood that reflux is a contributing etiology in presenting extraesophageal symptoms. Best Practice Advice 8: Surgical fundoplication is discouraged in those with extra esophageal reflux symptoms unresponsive to aggressive PPI therapy. Best Practice Advice 9: Fundoplication should only be considered in those with a mechanical defect (e.g., hiatal hernia), moderate to severe reflux at baseline off PPI therapy who have continued reflux despite PPI therapy and have failed more conservative non-GI treatments.

Medical Therapy of Gastroesophageal Reflux Disease Beyond Proton Pump Inhibitors: Where Are We Heading?

Proton pump inhibitors (PPI) have greatly improved the treatment of gastroesophageal reflux disease. However, recent investigations have revealed that reflux symptoms persist in a substantial number of patients. Therefore, treatment strategies beyond PPI are urgently required. One such strategy may involve more reliable acid suppression, e.g., with new acid inhibitory drugs. Furthermore, the rapid appearance of an acidic compartment in the proximal stomach after a meal, which is largely responsible for postprandial heartburn, requires a specific kind of therapy in addition to PPI which still needs to be established. Pharmacological augmentation of the lower esophageal sphincter may represent another approach to diminish reflux, but the clinical efficacy of compounds tested so far is limited. Altered e-sophageal perception represents a major component involved in the generation of reflux symptoms, particularly in non-erosive reflux disease, but effective pharmacological intervention is largely lacking. Presumed reflux-induced respiratory symptoms (cough, laryngitis, etc.) in the absence of typical esophageal symptoms (e.g., heartburn) remain a hot topic, but recent research points towards a hypersensitivity syndrome and only a minor role of gastroesophageal reflux. Treatment options for this condition are still pending.

The diagnostic value of pepsin detection in saliva for gastro-esophageal reflux disease: a preliminary study from China

Background

None of current diagnostic methods has been proven to be a reliable tool for gastro-esophageal reflux disease (GERD). Pepsin in saliva has been proposed as a promising diagnostic biomarker for gastro-esophageal reflux. We aimed to determine the diagnostic value of salivary pepsin detection for GERD.

Methods

Two hundred and fifty patients with symptoms suggestive of GERD and 35 asymptomatic healthy volunteers provided saliva on morning waking, after lunch and dinner for pepsin determination using the Peptest lateral flow device. All patients underwent 24-h multichannel intraluminal impedance pH (24-h MII-pH) monitoring and upper gastrointestinal endoscopy. Based on 24-h MII-pH and endoscopy study, patients were defined as GERD (abnormal MII-pH results and/or reflux esophagitis) and non-GERD otherwise.

Results

Patients with GERD had a higher prevalence of pepsin in saliva and higher pepsin concentration than patients with non-GERD and healthy controls (P < 0.001 for all). The pepsin test had a sensitivity of 73% and a specificity of 88.3% for diagnosing GERD using the optimal cut-off value of 76 ng/mL. Postprandial saliva samples collected when the symptoms occurred had a more powerful ability to identify GERD.

Conclusions

Salivary pepsin test had moderate diagnostic value for GERD. It may be a promising tool to replace the use of currently invasive tools with advantages of non-invasive, easy to perform and cost effective.

Trial registration

ChiCTR-DDD-16009506 (date of registration: October 20, 2016).

Facts and Fantasies on Extraesophageal Reflux: A Gastroenterologist Perspective

Gastroesophageal reflux disease encompasses a wide spectrum of disorders related to the reflux of gastric contents into the esophagus. Extraesophageal reflux (EER) may be suspected in patients with unexplained chronic cough, pharyngolaryngeal symptoms, and asthma. For physicians, suspected EER is challenging as there is currently no tool that can reliably make a definitive diagnosis. Endoscopic signs are not specific, pharyngeal and proximal reflux monitoring are not reliable, and if distal pH or pH-impedance monitoring can identify patients with abnormal reflux, they cannot predict the response to therapy. Controlled randomized trials have failed to reliably demonstrate any benefit of high-dose proton-pump inhibitors over placebo in patients with laryngeal symptoms, chronic cough, and asthma. Overall, the role of gastroesophageal reflux has been largely overestimated in patients with suspected EER. Especially when proton-pump inhibitors failed to improve symptoms, other diagnosis should be considered, such as functional laryngeal disorders which are probably much more prevalent in these patients than pathologic gastroesophageal reflux.