Esophageal Motor Dysfunctions in Gastroesophageal Reflux Disease and Therapeutic Perspectives

Utilizing Esophageal Motility Tests in Diagnosing and Evaluating Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD), a prevalent clinical condition, is often attributed to aberrant esophageal motility, leading to gastric content reflux and associated symptoms or complications. The rising incidence of GERD presents an escalating healthcare challenge. Endoscopic and esophageal reflux monitoring can provide a basis for the diagnosis of patients with gastroesophageal reflux disease, but when the diagnostic basis is at an inconclusive value, some additional supportive evidence will be needed. Advanced technology is the key to improving patient diagnosis, accurate assessment, and the development of effective treatment strategies. High-resolution esophageal manometry (HREM) and endoscopic functional lumen imaging probe (EndoFLIP) represent the forefront of esophageal motility assessment. HREM, an evolution of traditional esophageal manometry, is considered the benchmark for identifying esophageal motility disorders. Its widespread application in esophageal dynamics research highlights its diagnostic significance. Concurrently, EndoFLIP's emerging clinical relevance is evident in diagnosing and guiding the treatment of coexisting esophageal motility issues. This review integrates contemporary research to delineate the contributions of HREM, EndoFLIP, and novel technologies in GERD. It examines their efficacy in facilitating an accurate diagnosis, differentiating similar gastrointestinal disorders, quantifying the extent of reflux, assessing the severity of the disease, forecasting patient responsiveness to proton pump inhibitor therapy, and guiding decisions for surgical interventions. The overarching aim is to deepen the understanding of GERD's underlying mechanisms and advance the formulation of holistic, efficacious treatment approaches.

The prevalence of gastroesophageal reflux disease and laryngopharyngeal reflux in patients with dysphagia after radiotherapy for nasopharyngeal carcinoma

BACKGROUND

The prevalence of gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) in post-irradiated patients with nasopharyngeal carcinoma (NPC) is unknown.

MATERIALS AND METHODS

In a cross-sectional study, 31 NPC and 12 control patients completed questionnaires for GERD/LPR before esophageal manometry and 24-h pH monitoring. The DeMeester score and reflux finding score (RFS) were used to define GERD and LPR, respectively. Risk factors were identified.

RESULTS

51.6% of NPC and 8.3% of control patients, and 77.4% of NPC and 33% of control patients, were GERD-positive and LPR-positive, respectively. The GERD/LPR questionnaire failed to identify either condition in patients with NPC. No parameter differences in esophageal manometry or pneumonia incidence were noted between GERD/LPR-positive and GERD/LPR-negative patients. Post radiotherapy duration, high BMI, lack of chemotherapy, and dysphagia were positive risk factors for GERD/LPR.

CONCLUSIONS

A high prevalence of GERD/LPR in patients with post-irradiated NPC exists, but reflux symptoms are inadequate for diagnosis.

Analysis of the Correlation Between Dynamic Characteristics and Symptoms of Gastroesophageal Reflux Disease

OBJECTIVE

To investigate the esophageal motility characteristics of gastroesophageal reflux disease (GERD) and their relationship with symptoms.

PATIENTS AND METHODS

We examined 101 patients diagnosed with GERD by endoscopy and divided them into 3 groups as follows: nonerosive reflux disease (NERD), reflux esophagitis, and Barrett esophagus. Esophageal high-resolution manometry and the GERD Questionnaire were used to investigate the characteristics of esophageal dynamics and symptoms. In addition, the reflux symptom index was completed and the patients were divided into 7 groups according to symptoms. We then determined the correlation between dynamic esophageal characteristics and clinical symptoms.

RESULTS

Upper (UES) and lower (LES) esophageal sphincter pressures and the 4-second integrated relaxation pressure in the RE group were lower than those in the NERD group. The 4-second integrated relaxation pressure in the Barrett esophagus group was also lower than that in the NERD group. In the analysis of extraesophageal symptoms, high-resolution manometry showed significant differences in UES pressures among all groups. Further subgroup analysis showed that compared with the group without extraesophageal symptoms, the UES pressure of the groups with pharyngeal foreign body sensation, throat clearing, and multiple extraesophageal symptoms was lower.

CONCLUSIONS

As GERD severity increases, motor dysfunction of the LES and esophageal body gradually worsens, and the LES plays an important role in GERD development. Decreased UES pressure plays an important role in the occurrence of extraesophageal symptoms, which is more noticeable in patients with pharyngeal foreign body sensation and throat clearing.

Thyroid disorders and gastrointestinal dysmotility: an old association

Gastrointestinal motility symptoms may be closely related to thyroid diseases. Sometimes, such symptoms are the only thyroid disease-related clue although the degree of the symptoms may vary. The exact mechanism of action of thyroid hormones on gastrointestinal motility is not completely understood, however, a clue lies in the fact that muscle cell receptors can be directly acted upon by thyroxines. Both hypo- and hyperthyroidism can cause impairment of gastrointestinal motility, modifying structure and function of pharynx and esophagus, and regulating esophageal peristalsis through neuro-humoral interaction. In hyperthyroid patients, alterations of postprandial and basic electric rhythms have been observed at gastro-duodenal level, often resulting in slower gastric emptying. Gastric emptying may also be delayed in hypothyroidism, but an unrelated gastric mucosa-affecting chronic modification may also cause such pattern. Hyperthyroidism commonly show malabsorption and diarrhoea, while hypothyroidism frequently show constipation. In summary, it can be stated that symptoms of gastrointestinal motility dysfunction can be related to thyroid diseases, affecting any of the gastrointestinal segment. Clinically, the typical thyroid disease manifestations may be missing, borderline, or concealed because of intercurrent sicknesses. Motility-linked gastrointestinal problems may easily conceal a misdetected, underlying dysthyroidism that should be carefully analyzed. Here, we aim to elaborate on the associations between thyroid disorders and GI dysmotility and the common clinical manifestations associated with GI dysmotility.

Anatomic and Manometric Abnormalities of the Upper and Lower Esophageal Sphincters in Patients With Reflux Disease

RESEARCH QUESTION

Laryngopharyngeal reflux (LPR) may cause inflammation of the laryngeal and pharyngeal mucosa. Gastroesophageal reflux disease (GERD) involves retrograde flow of gastric content into the esophagus below the upper esophageal sphincter (UES). The goal of this study was to investigate the esophageal anatomical and manometric variations of the esophagus in patients with LPR and/or GERD.

METHODS

Adult voice center patients who underwent diagnostic workup for reflux complaints with 24-hour multichannel intraluminal pH-impedance testing and esophageal manometry were included in this retrospective study. Subjects were classified as having LPR (>10 proximal reflux events), LPR + GERD (>10 proximal reflux events plus >73 distal reflux events) or were assigned to a control group (≤10 proximal events and ≤73 distal reflux events) based on pH study results. Anatomic and manometric parameters were evaluated between groups.

RESULTS

There were 169 cases (65 male, 104 female) included in this study. The average age was 50.50 ± 17.29. Subjects in the LPR group had significantly higher UES relaxation pressures and greater UES length compared with the control group. Lower esophageal sphincter relaxation pressure was significantly higher in the control group compared with the LPR group or the GERD + LPR group. Subjects in the GERD + LPR group had a significantly shorter intra-abdominal portion of the lower esophageal sphincter compared with the LPR only group and the control group. Intrabolus pressure was significantly lower in both the LPR group and the LPR + GERD group compared with the control group. Distal wave amplitude was significantly lower in the LPR + GERD group compared to both the LPR group and the control group. The percentage of swallows with incomplete clearance was significantly greater in the LPR + GERD group than both the control group and the LPR group. The LPR group had significantly fewer swallows with incomplete clearance than the control group.

CONCLUSIONS

Anatomic and manometric abnormalities are present in subjects with LPR with or without GERD and may contribute to the pathogenesis of reflux disease. Further research is needed to confirm or refute these findings.

Esophageal Motility Abnormalities in Lung Transplant Recipients With Esophageal Acid Reflux Are Different From Matched Controls

Background/Aims

There is an increased incidence of gastroesophageal reflux disease (GERD) after lung transplantation (LT) that can be associated with graft dysfunction. It is unclear if the underlying esophageal motility changes in GERD are different following LT. This study aimed to use esophageal high-resolution manometry (HRM) to explore GERD mechanisms in LT recipients compared to matched controls.

Methods

This was a retrospective study including patients with pathologic acid reflux who underwent HRM and pH testing at our healthcare facility July 2012 to October 2019. The study included 12 LT recipients and 36 controls. Controls were matched in a 1:3 ratio for age, gender, and acid exposure time (AET).

Results

LT recipients had less hypotensive esophagogastric junction (EGJ) (mean EGJ-contractile integral 89.2 mmHg/cm in LT vs 33.9 mmHg/cm in controls, P < 0.001). AET correlated with distal contractile integral and total EGJ-contractile integral only in LT group (r = -0.79, P = 0.002 and r = -0.57, P = 0.051, respectively).

Conclusions

Following LT, acid reflux is characterized by a less hypotensive EGJ compared to controls with similar AET. The strongest correlation with AET after LT was found to be esophageal peristaltic vigor. These results add to the understanding of reflux after LT and may help tailor an individualized treatment plan.

The Time-Point Distribution Characteristics of Laryngopharyngeal Reflux in Elderly Patients

OBJECTIVE

To identify the characteristics of the time-point distribution of the occurrence of hypopharyngeal-proximal reflux episodes (HREs) in elderly and younger patients with laryngopharyngeal reflux (LPR).

STUDY DESIGN

Retrospective cohort study.

SETTING

Analysis of data from patients with LPR-related symptoms and 24-hour hypopharyngeal-esophageal multichannel intraluminal impedance-pH (24-hour HEMII-pH) monitoring from February 2017 to September 2022 at Sixth Medical Center of PLA General Hospital.

METHODS

Patients were divided into 2 age groups: the elderly group (>60 years) and the younger group (≤60 years). The time series of HREs and meals within 24 hours were analyzed based on HEMII-pH.

RESULTS

A total of 305 patients were included (126 elderly patients). In younger patients, except for nonacid-gas HREs, the incidence of the remaining types of HREs tended to increase within 2 hours after meals, especially after dinner. The incidence of all types of HREs pre- and postmeal was not significantly different in the elderly group (χ2  = 0.080, P = .777). The incidence of nighttime HREs in elderly patients was statistically higher than in younger patients (6.23% vs 3.96%, P = .030), particularly acid-/nonacid-liquid HREs.

CONCLUSION

HREs tend to increase within 2 hours after meals in younger LPR patients, except for nonacid-gas HREs. In elderly LPR patients, the incidence of all types of HREs pre- and postmeal were not significantly different, and nighttime fluid HREs was more prone to occur than in younger patients.

Pressure dynamics of the esophagogastric junction at rest and during inspiratory maneuvers after Nissen fundoplication

Low sphincter pressure and inability of the crural diaphragm to elevate it at the esophagogastric junction are important pathophysiological mechanisms of gastroesophageal reflux disease (GERD). The object of this study was to depict how Nissen fundoplication changed the resting and inspiratory pressures of the anti-reflux barrier. We selected 14 patients (eight males; mean age 42.7 years; mean body mass index 27.8) for surgery. They answered symptoms questionnaires and underwent high-resolution manometry (HRM) before and 6 months after Nissen fundoplication. We used a standard manometric protocol (resting and liquid swallows) and assessment of esophagogastric junction (EGJ) pressure metrics during standardized forced inspiratory maneuvers against increasing loads (Threshold Maneuvers). We used the Wilcoxon test for comparison of pre and postoperative data. After fundoplication, heartburn and regurgitation scores diminished remarkably (from 4.5 and 2, respectively, to zero; P = 0.002 and P = 0.0005, respective medians). Also, the median expiratory EGJ pressure had a significant increase from 8.1 to 18.1 mmHg (P = 0.002), while mean respiratory pressure and EGJ contractility integral (EGJ-CI) increased without statistical significance (P = 0.064 and P = 0.06, respectively). Axial EGJ displacement was lower after fundoplication. The EGJ relaxation pressure (P = 0.001), the mean distal esophageal intrabolus pressure (P = 0.01) and the distal latency (P = 0.017) increased after fundoplication. There was a reduction in the contraction front velocity (P = 0.043). During evaluation with standardized inspiratory maneuvers, the inspiratory EGJ pressures (under loads of 12, 24, 36 and 48 cmH2O) were lower after surgery for all loads (median for load 12 cmH2O: 145.6 vs. 102.7 mmHg; P = 0.004). Fundoplication and hiatal closure increased the expiratory EGJ pressure and promoted a great GERD symptom relief. The surgery seemed to overcompensate a reduced EGJ mobility and inspiratory pressure.

Evaluating the causal relationship between human blood metabolites and gastroesophageal reflux disease

BACKGROUND

Gastroesophageal reflux disease (GERD) affects approximately 13% of the global population. However, the pathogenesis of GERD has not been fully elucidated. The development of metabolomics as a branch of systems biology in recent years has opened up new avenues for the investigation of disease processes. As a powerful statistical tool, Mendelian randomization (MR) is widely used to explore the causal relationship between exposure and outcome.

AIM

To analyze of the relationship between 486 blood metabolites and GERD.

METHODS

Two-sample MR analysis was used to assess the causal relationship between blood metabolites and GERD. A genome-wide association study (GWAS) of 486 metabolites was the exposure, and two different GWAS datasets of GERD were used as endpoints for the base analysis and replication and meta-analysis. Bonferroni correction is used to determine causal correlation features (P < 1.03 × 10-4). The results were subjected to sensitivity analysis to assess heterogeneity and pleiotropy. Using the MR Steiger filtration method to detect whether there is a reverse causal relationship between metabolites and GERD. In addition, metabolic pathway analysis was conducted using the online database based MetaboAnalyst 5.0 software.

RESULTS

In MR analysis, four blood metabolites are negatively correlated with GERD: Levulinate (4-oxovalerate), stearate (18:0), adrenate (22:4n6) and p-acetamidophenylglucuronide. However, we also found a positive correlation between four blood metabolites and GERD: Kynurenine, 1-linoleoylglycerophosphoethanolamine, butyrylcarnitine and guanosine. And bonferroni correction showed that butyrylcarnitine (odd ratio 1.10, 95% confidence interval: 1.05-1.16, P = 7.71 × 10-5) was the most reliable causal metabolite. In addition, one significant pathways, the "glycerophospholipid metabolism" pathway, can be involved in the pathogenesis of GERD.

CONCLUSION

Our study found through the integration of genomics and metabolomics that butyrylcarnitine may be a potential biomarker for GERD, which will help further elucidate the pathogenesis of GERD and better guide its treatment. At the same time, this also contributes to early screening and prevention of GERD. However, the results of this study require further confirmation from both basic and clinical real-world studies.

Oesophageal stasis is a risk factor for chronic lung allograft dysfunction and allograft failure in lung transplant recipients

Background

Morbidity and mortality in lung transplant recipients are often triggered by recurrent aspiration events, potentiated by oesophageal and gastric disorders. Previous small studies have shown conflicting associations between oesophageal function and the development of chronic lung allograft dysfunction (CLAD). Herein, we sought to investigate the relationship between oesophageal motility disorders and long-term outcomes in a large retrospective cohort of lung transplant recipients.

Methods

All lung transplant recipients at the Toronto Lung Transplant Program from 2012 to 2018 with available oesophageal manometry testing within the first 7 months post-transplant were included in this study. Patients were categorised according to the Chicago Classification of oesophageal disorders (v3.0). Associations between oesophageal motility disorders with the development of CLAD and allograft failure (defined as death or re-transplantation) were assessed.

Results

Of 487 patients, 57 (12%) had oesophagogastric junction outflow obstruction (OGJOO) and 47 (10%) had a disorder of peristalsis (eight major, 39 minor). In a multivariable analysis, OGJOO was associated with an increased risk of CLAD (HR 1.71, 95% CI 1.15-2.55, p=0.008) and allograft failure (HR 1.69, 95% CI 1.13-2.53, p=0.01). Major disorders of peristalsis were associated with an increased risk of CLAD (HR 1.55, 95% CI 1.01-2.37, p=0.04) and allograft failure (HR 3.33, 95% CI 1.53-7.25, p=0.002). Minor disorders of peristalsis were not significantly associated with CLAD or allograft failure.

Conclusion

Lung transplant recipients with oesophageal stasis characterised by OGJOO or major disorders of peristalsis were at an increased risk of adverse long-term outcomes. These findings will help with risk stratification of lung transplant recipients and personalisation of treatment for aspiration prevention.

Differences in Dietary and Lifestyle Triggers between Non-Erosive Reflux Disease and Reflux Esophagitis-A Multicenter Cross-Sectional Survey in China

The occurrence of gastroesophageal reflux disease (GERD) and symptom onset are closely associated with diet. We aimed to compare the dietary and lifestyle triggers between non-erosive reflux disease (NERD) and reflux esophagitis (RE) in Chinese patients and to provide evidence for development of practical dietary modifications for GERD. A multicenter cross-sectional survey was conducted. A total of 396 GERD patients with typical gastroesophageal reflux symptoms who received upper endoscopy in the previous month were enrolled, including 203 cases of NERD patients and 193 cases of RE patients. All participants completed questionnaires including demographic data, reflux symptoms, previous management, dietary and lifestyle habits, triggers of reflux symptoms, psychological status, and quality of life. There were no significant differences in GERD symptom scores between NERD and RE. RE patients had a higher male proportion and smoking/drinking and overeating rates than NERD patients. In the NERD group, more patients reported that fruits, dairy products, yogurt, bean products, cold food, and carbonated beverages sometimes and often induced reflux symptoms and had more triggers compared to RE patients. The number of triggers was positively correlated to GERD symptom score and GERD-HRQL score in both NERD and RE patients. However, 74.0% of GERD patients still often consumed the triggering foods, even those foods that sometimes and often induced their reflux symptoms, which might be related to the reflux relapse after PPI withdrawal considering NERD and RE patients had similar GERD symptom severity. There were some differences in terms of dietary habits, dietary and lifestyle triggers, and related quality of life between NERD and RE, and these results may provide evidence of different approaches toward the dietary modification of NERD and RE patients.

Breathing Exercises in Gastroesophageal Reflux Disease: A Systematic Review

The pathogenesis of gastroesophageal reflux disease (GERD) is multifactorial. The severity of abnormal reflux burden corresponds to the dysfunction of the antireflux barrier and inability to clear refluxate. The crural diaphragm is one of the main components of the esophagogastric junction and plays an important role in preventing gastroesophageal reflux. The diaphragm, as a skeletal muscle, is partially under voluntary control and its dysfunction can be improved via breathing exercises. Thus, diaphragmatic breathing training (DBT) has the potential to alleviate symptoms in selected patients with GERD. High-resolution esophageal manometry (HRM) is a useful method for the assessment of antireflux barrier function and can therefore elucidate the mechanisms responsible for gastroesophageal reflux. We hypothesize that HRM can help define patient phenotypes that may benefit most from DBT, and that HRM can even help in the management of respiratory physiotherapy in patients with GERD. This systematic review aimed to evaluate the current data supporting physiotherapeutic practices in the treatment of GERD and to illustrate how HRM may guide treatment strategies focused on respiratory physiotherapy.

Updates on Surgical Treatment for Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a common condition that is on the rise. Obesity is one risk factor that has increased in parallel with the rise of GERD. Typical symptoms include heartburn, regurgitation, dysphagia, cough, and chest pain. Patients with typical symptoms are empirically treated with proton pump inhibitors (PPIs). If the diagnosis is not clear, further evaluation is performed with endoscopy, pH monitoring, and esophageal manometry. Untreated GERD increases the risk of esophagitis, esophageal stricture, Barrett's esophagus, and esophageal adenocarcinoma. Treatment begins with lifestyle modification and medical therapy. If these fail, surgical and endoscopic surgical techniques are available, to provide treatment, symptom relief, and reduce long-term PPI use.

Underlying etiology associated with the diagnosis of absent contractility on high resolution esophageal manometry

BACKGROUND/AIMS

Absent contractility is considered a disorder of peristalsis. The literature about the etiology and clinical characteristics is scarce and the evidence on systemic diseases associated with this esophageal disorder is limited. Therefore, we aimed to determine the etiology of absent contractility in our population using the clinical algorithm recently described in the literature.

METHODS

We conducted a retrospective, descriptive study at a single tertiary hospital of all patients diagnosed of absent contractility between May 2018 and February 2020. Data on demographic characteristics, medication, comorbidities, and laboratory and paraclinical tests were recorded from clinical records.

RESULTS

A total of 72 patients with absent contractility were included for analysis. There was a predominance of female sex (n=43, 59.7%), with a mean age of 55.4 (±15.0) years. We identified a systemic disorder associated with absent contractility in 64 (88.9%) patients. From these, 31 (43.1%) patients were diagnosed with a systemic autoimmune disease, 26 (36.1%) patients were considered to have absent contractility secondary to pathological exposure to acid-reflux and 15 (20.8%) patients were diagnosed with other non-autoimmune systemic disorders. In the remaining eight (11.1%) patients, there were no underlying systemic disorders that could justify the diagnosis of absent contractility.

CONCLUSIONS

A systematic approach to search for an underlying cause in patients diagnosed with absent contractility is warranted. Up to 90% of patients with absent contractility have a systemic disorder associated with this condition.

Concise Review: Applicability of High-resolution Manometry in Gastroesophageal Reflux Disease

Manometry, particularly high-resolution manometry is the preferred diagnostic tool used to evaluate esophageal motor function. This investigation is strongly indicated in the setting of dysphagia, but is also useful in gastroesophageal reflux disease (GERD), especially in case of failure of conventional treatment to exclude alternative diagnoses and prior to anti-reflux surgery. Moreover, ineffective esophagogastric junction barrier function and esophageal motor dysfunction are pathophysiological mechanisms in GERD and can be identified by manometry. The recent international guidelines have positioned high-resolution manometry as an important part of functional diagnostic work up in GERD in order to identify the GERD phenotype to guide specific treatment. The proposed manometric identification and measurement is based on the Chicago classification version 4.0 adding with new established metrics for GERD evaluation.

Functional Luminal Imaging Probe in the Management of Pediatric Esophageal Disorders

BACKGROUND

Functional luminal imaging probe (FLIP) measures pressure-geometry relationships of digestive luminal space. When used in esophageal disorders, it provides several luminal parameters that help better understand the pathophysiology. Data about the potential utility of FLIP in pediatrics are scarce and there is no standardized use in children. We aim to describe the use of FLIP in our center, its safety, feasibility, and clinical impact in esophageal disorders in children.

METHODS

Consecutive FLIP recordings performed at the Centre Hospitalier Universitaire-Sainte-Justine, Montréal, Canada between February 2018 and January 2021 were extracted. A chart review was conducted for demographics and medical history. Symptomatology after the procedure was evaluated with validated dysphagia scores.

KEY RESULTS

Nineteen patients were included (11 girls, median age 16 years, range 3.2-19.6) with achalasia (n = 5), post-Heller's myotomy dysphagia (n = 3), esophagogastric junction outflow obstruction (n = 3), congenital esophageal stenosis (n = 2); post-esophageal atresia repair stricture (n = 3), and post-fundoplication dysphagia (n = 3). There was no significant correlation between integrated relaxation pressure measured with high resolution manometry and distensibility index (DI). The use of FLIP made it possible to differentiate between dysphagia related to an esophageal obstruction (DI < 2.8 mm2/mmHg) and dysphagia without major motility disorder (DI > 2.8 mm2/mmHg) that guided the indication for dilation. FLIP led to a change in management in 47% of the patients. Forty-seven percent of the patients were symptom free at the time of the evaluation.

CONCLUSIONS INFERENCES

FLIP provides key esophageal luminal values and therefore can play an important role in pediatric esophageal disorders management.

Comparative Study of Salivary pH, Buffer Capacity, and Flow in Patients with and without Gastroesophageal Reflux Disease

The oral cavity has specific and individualized characteristics, with pH, saliva flow, buffer capacity, temperature, and microorganisms content influencing oral health. Currently, the prevalence of gastroesophageal reflux disease (GERD) is constantly increasing. The objective of this study was to evaluate and compare the saliva quantity at 5 min, salivary pH, and salivary buffer capacity in patients with and without GERD, necessary for establishing the correct dental treatment plan. A Saliva-Check Buffer (GC) kit was used for the determination of salivary variables. The total number of 80 patients included in the study were divided into a study group and a control group, each containing 40 patients. Saliva quantity at 5 min was lower in patients suffering from GERD. The salivary pH of these patients turned to acid values compared to the salivary pH of controls, where the values were within the normal range. In patients with GERD, the determined salivary buffer capacity was low or very low. The use of the Saliva-Check Buffer (GC) kit is a simple, easy, non-invasive and patient-accepted method, which can also be used in the dentist’s office to assess the saliva buffer capacity and pH, variables that are important for establishing a correct dental treatment plan.

Current Advancement on the Dynamic Mechanism of Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a common clinical disease associated with upper gastrointestinal motility disorders. Recently, with improvements in living standards and changes in lifestyle and dietary habits, the incidence of GERD has been increasing yearly. However, the mechanism of GERD has not been fully elucidated due to its complex pathogenesis, and this had led to unsatisfactory therapeutic outcomes. Currently, the occurrence and development of GERD involve multiple factors. Its pathogenesis is mainly thought to be related to factors, such as lower esophageal sphincter pressure, transient lower esophageal sphincter relaxation, crural diaphragmatic dysfunction, hiatus hernia, and impaired esophageal clearance. Therefore, explaining the pathogenesis of GERD more clearly and systematically, exploring potential and effective therapeutic targets, and choosing the best treatment methods have gradually become the focus of scholars' attention. Herein, we reviewed current advancements in the dynamic mechanism of GERD to better counsel patients on possible treatment options.

Usefulness of matrix metalloproteinase-7 in saliva as a diagnostic biomarker for laryngopharyngeal reflux disease

Several diagnostic methods are currently being used to diagnose LPRD (laryngopharyngeal reflux disease), but have the disadvantage of being invasive, subjective, or expensive. Our purpose in this study was to investigate the correlation between pepsin and MMP-7 (Matrix Metalloproteinase-7) in pharyngeal secretions of subjects according to RSI (Reflux Symptom Index) score to find out the diagnostic value of MMP-7. We recruited 173 subjects aged between 19 and 85 years who completed the RSI scale. All samples were taken after waking up, and the amount of the pepsin and MMP-7 in saliva were measured by means of an enzyme activity assay. There was a significant increase of pepsin and MMP-7 activity in the study group with an RSI score of 13 or higher. The sensitivity and specificity of MMP-7 for predicting the possibility of an RSI of 13 or more was higher than that of pepsin. When MMP-7 and pepsin were combined, this sensitivity and specificity increased. An enzyme assay of MMP-7 in saliva may be a noninvasive and easy technique for diagnosing LPRD.

Experimental Study Regarding the Behavior at Different pH of Two Types of Co-Cr Alloys Used for Prosthetic Restorations

Cobalt-chromium (Co-Cr) alloys are widely utilized in dentistry. The salivary pH is a significant factor, which affects the characteristics and the behavior of dental alloys through corrosion. This study aimed to evaluate the corrosion behavior in artificial saliva with different pH values (3, 5.7, and 7.6) of two commercial Co-Cr dental alloys manufactured by casting and by milling. Corrosion resistance was determined by the polarization resistance technique, and the tests were carried out at 37 ± 1 °C, in Carter Brugirard artificial saliva. After the electrochemical parameters, it can be stated that the cast Co-Cr alloy has the lowest corrosion current density, the highest polarization resistance, and the lowest speed of corrosion in artificial saliva with pH = 7.6. In the case of milled Co-Cr alloy, the same behavior was observed, but in artificial saliva with pH = 5.7, it recorded the most electropositive values of open circuit potential and corrosion potential. Although both cast and milled Co-Cr alloys presented a poorer corrosion resistance in artificial saliva with a more acidic pH value, the milled Co-Cr alloy had better corrosion behavior, making this alloy a better option for the prosthetic treatment of patients suffering from GERD.

The mechanism of esophagus dysmotility in diabetes and research progress of relating treatments

Introduction: Esophagus dysmotility is a crucial risk factor of gastroesophageal reflux disease (GERD), which is one of the most common diseases in digestive medicine globally. This review emphasizes the mechanisms of esophagus dysmotility in diabetes and summarizes more targeted treatments for these patients to avoid the overuse of proton pump inhibitors (PPIs).Areas covered: Diabetes mellitus (DM) is a clear factor that must not be neglected in the development of GERD. Previous studies have preliminarily researched the esophagus deterioration in diabetes. However, the multi-faceted mechanisms of esophagus dysmotility in diabetes need more studies. Besides, targeted treatments for these patients rather than conventional PPIs are urgently needed.Expert opinion: The treatments for GERD patients with diabetes should be further explored. Pharmacological approaches such as prokinetic agents, psychotherapy can be adopted. Meanwhile, it's feasible to explore non-drug treatments. For example, Electroacupuncture (EA) at Zusanli (ST-36) may be effective to protect the networks of intestinal cells of Cajal (ICCs) in diabetes. More effective approaches should be explored to achieve individualized treatment for these patients.

Characterisation of patients with supine nighttime reflux: observations made with prolonged wireless oesophageal pH monitoring

BACKGROUND

Although nighttime reflux symptoms are common, the presence of nocturnal reflux is seldom confirmed with a standard 24 hours pH study.

AIM

To study patients with supine nighttime reflux symptoms using prolonged wireless pH monitoring.

METHODS

In this retrospective study, patients with typical acid reflux symptoms were studied using 96-h pH monitoring. Patients with nighttime reflux symptoms were compared to those without. Night-to-night variability and diagnostic accuracy of 24-, 48- and 72-hours pH studies compared to the 96-hours "gold standard" were evaluated.

RESULTS

Of the 105 included patients (61.9% females; mean age 46.8 ± 14.4 years), 86 (81.9%) reported nighttime reflux symptoms, of which 67.4% had pathological supine nocturnal acid exposure in at least one night. There was high variance in night-to-night acid exposure (94% [IQR0-144]), which was larger than the variance in upright acid exposure (58% [IQR32-88]; P < 0.001). When analysing the first 24 hours of the pH study, 32% of patients were diagnosed with pathological supine nighttime acid exposure versus 51% of patients based upon the 96-hours pH-test. The diagnostic accuracy and yield improved with study duration (P < 0.001). Reflux episodes with a lower nadir pH or longer acid clearance time were more prone to provoke nightly symptoms.

CONCLUSIONS

The majority of patients with nocturnal reflux symptoms had pathological acid exposure in at least one night of the prolonged pH recording. A high night-to-night variability in acid exposure reduces the clinical value and diagnostic yield of pH monitoring limited to 24 hours. Prolonged testing is a more appropriate diagnostic tool for patients with nocturnal reflux symptoms.

Management of Ineffective Esophageal Hypomotility

Esophageal hypomotility in general and especially ineffective esophageal motility according to the Chicago criteria of primary motility disorders of the esophagus, is one of the most frequently diagnosed motility disorders on high resolution manometry and results in a large number of patients visiting gastroenterologists. Most patients with esophageal hypomotility present with gastroesophageal reflux symptoms or dysphagia. The clinical relevance of the motility pattern, however, is not well established but seems to be correlated with disease severity in reflux patients. The correlation with dysphagia is less clear. Prokinetic agents are commonly prescribed as first line pharmacologic intervention to target esophageal smooth muscle contractility and improve esophageal motor functions. However, the beneficial effects of these medications are limited and only confined to some specific drugs. Serotonergic agents, including buspirone, mosapride and prucalopride have been shown to improve parameters of esophageal motility although the effect on symptoms is less clear. Understanding on the complex correlation between esophageal hypomotility and esophageal symptoms as well as the limited evidence of prokinetic agents is necessary for physicians to appropriately manage patients with Ineffective Esophageal Motility (IEM).

Non-surgical animal model of gastroesophageal reflux disease by overeating induced in mice

Previous animal models of gastroesophageal reflux disease (GERD) were not physiological and required a variety of surgical procedures. Therefore, the animal model developed by conditions that are similar to the pathogenesis of GERD is necessary. The aim is to establish a non-surgical animal model with GERD caused by overeating induced in mice. To induce mice to overeat, we designed dietary control protocols including repetitive fasting and feeding. The esophageal tissues were evaluated with GERD markers to prove the establishment of a GERD animal model. Mice fasted every other day (group 2) showed more pronounced overeating feature and demonstrated evident changes similar to the macroscopic and microscopic findings of GERD, the expressions of inducible nitric oxide synthase and substance P were stronger. The higher frequency of fasting and overeating could cause GERD effectively. The dietary control can make mice overeat, which elicits the change of lower esophageal mucosa similar to GERD. Thus, the overeating-induced mouse may be used as a GERD mouse model.

Manometric and pH-monitoring changes after laparoscopic sleeve gastrectomy: a systematic review

PURPOSE

Aim of this systematic review is to assess the changes in esophageal motility and acid exposure of the esophagus through esophageal manometry and 24-hours pH-monitoring before and after laparoscopic sleeve gastrectomy (LSG).

METHODS

Articles in which all patients included underwent manometry and/or 24-hours pH-metry or both, before and after LSG, were included. The search was carried out in the PubMed, Embase, Cochrane, and Web of Science databases, revealing overall 13,769 articles. Of these, 9702 were eliminated because they have been found more than once between the searches. Of the remaining 4067 articles, further 4030 were excluded after screening the title and abstract because they did not meet the inclusion criteria. Thirty-seven articles were fully analyzed, and of these, 21 further articles were excluded, finally including 16 articles.

RESULTS

Fourteen and twelve studies reported manometric and pH-metric data from 402 and 547 patients, respectively. At manometry, a decrease of the lower esophageal sphincter resting pressure after surgery was observed in six articles. At 24-hours pH-metry, a worsening of the DeMeester score and/or of the acid exposure time was observed in nine articles and the de novo gastroesophageal reflux disease (GERD) rate that ranged between 17.8 and 69%. A meta-analysis was not performed due to the heterogeneity of data.

CONCLUSIONS

After LSG a worsening of GERD evaluated by instrumental exams was observed such as high prevalence of de novo GERD. However, to understand the clinical impact of LSG and the burden of GERD over time further long-term studies are necessary.

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.

Understanding gastroesophageal reflux disease in children

ABSTRACT

Gastroesophageal reflux disease (GERD) is a common disorder with increasing prevalence in children. The diagnosis and management of GERD remains a challenge because of its nonspecific symptomatology from infancy through adolescence. Certain presenting alarm symptoms warrant a further, more extensive workup. Treatment of pediatric GERD begins with lifestyle and nonpharmacologic management, including postural adjustments, dietary changes, and weight loss if indicated. Pharmacologic interventions can be prescribed to relieve symptoms for patients whose disease does not respond to lifestyle management. Patients with refractory symptoms can be managed with surgical intervention. Complications may arise if GERD remains untreated, ranging from worsening oral health to failure to thrive.

A comparison of the efficacy and safety of complementary and alternative therapies for gastroesophageal reflux disease: A protocol for network meta-analysis

BACKGROUND

Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal diseases in the world and is showing increasing prevalence in some countries. The disease has a chronic course that leads to a significant decline in the quality of life of patients and is associated with a high economic burden worldwide. And complementary and alternative medicine is used to treat the disease. Over the past few decades, a number of randomized controlled trials and systematic evaluations have been conducted to evaluate the effectiveness and safety of different types of complementary and alternative medicine methods, so there is an urgent need to summarize and further evaluate these studies.

METHODS

We will search the following sources without restrictions for date, language, or publication status: PubMed, Cochrane Central Register of Controlled Trials (CENTRAL) Cochrane Library, and EMBASE, China National Knowledge Infrastructure, Chinese Bio-medicine Database, VIP Chinese Periodical Database, Wan Fang Database. We will apply a combination of Medical Subject Heading and free-text terms incorporating database-specific controlled vocabularies and text words to implement search strategies. We will also search the ongoing trials registered in the World Health Organization's International Clinical Trials Registry Platform. Besides, the previous relevant reviews conducted on complementary and alternative therapies for GERD and reference lists of included studies will also be searched.

RESULTS

This study will provide a reliable basis for the treatment of GERD with complementary and alternative therapies.

CONCLUSIONS

The findings will be an available reference to evaluate the efficacy and safety of complementary and alternative therapies on GERD and may provide decision-making reference on which method to choose for clinicians.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD42020169332.

Hypopharyngeal-Esophageal Impedance-pH Monitoring Profiles of Laryngopharyngeal Reflux Patients

OBJECTIVES/HYPOTHESIS

To investigate the profile of patients with laryngopharyngeal reflux (LPR) at hypopharyngeal-esophageal multichannel intraluminal impedance-pH (HEMII-pH) monitoring and the relationship between hypopharyngeal-proximal reflux episodes (HREs) and saliva pepsin concentration.

STUDY DESIGN

Prospective non-controlled.

METHODS

Patients were recruited from three European hospitals from January 2018 to October 2019. Patients benefited from HEMII-pH monitoring and saliva collections to measure saliva pepsin concentration in the same time. Saliva pepsin concentration was measured in the morning (fasting), after lunch, and after dinner. The LPR profile of patients was studied through a breakdown of the HEMII-pH findings over the 24 hours of testing. The relationship between the concentrations of saliva pepsin and 24-hour HREs was studied through linear multiple regression.

RESULTS

One hundred twenty-six patients completed the study. The HEMII-pH analyses revealed that 73.99% of HREs occurred outside 1-hour postmeal times, whereas 20.49% and 5.52% of HREs occurred during the 1-hour postmeal and nighttime, respectively. Seventy-four patients (58.73%) did not have nighttime HREs. Patients with both daytime and nighttime HREs had more severe HEMII-pH parameters and reflux symptom score compared with patients with only daytime HREs. There were no significant associations between HREs and saliva pepsin concentration.

CONCLUSIONS

Unlike gastroesophageal reflux disease, HREs occur less frequently after meals and nighttime. The analysis of the HEMII-pH profile of the LPR patients has to be considered to develop future personalized therapeutic strategies.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:268-276, 2021.

Efficacy of Chinese Herbal Formula Sini Zuojin Decoction in Treating Gastroesophageal Reflux Disease: Clinical Evidence and Potential Mechanisms

Background

Based on 122 cases reported in China, data mining indicated that Sini Powder (SNP) and the Zuojin Pill (ZJP) are both widely used as the basic recipe for treating Gastroesophageal Reflux Disease (GERD).

Objectives

To evaluate the intervention effects of Sini Zuojin Decoction (SNZJD) in patients with GERD.

Methods

A comprehensive collection of randomized controlled trials (RCTs) using SNZJD in patients with GERD that were published in domestic and foreign journals was made by computer retrieval. RevMan 5.3 software was used for meta-analysis and bias risk assessment, Stata 14.0 software was used for sensitivity analysis, GRADE profiler 3.6 was used to evaluate the level of evidence, and trial sequential analysis (TSA), employed to control for random errors, was performed to assess the main outcomes. Network pharmacology analysis was applied to preliminarily study the mechanisms of action of SNZJD on GERD.

Results

Thirteen articles were eventually included, covering a total of 966 patients. Meta-analysis indicated that: ① the SNZJD plus traditional stomach medicines (SPTSM) group was more effective than the traditional stomach medicines (TSM) group (RR = 1.16, 95% CI [1.04, 1.29], P = 0.009); ② the experimental group with SNZJD was significantly better than TSM controls in improving heartburn, substernal chest pain, acid regurgitation, and food regurgitation symptoms (P < 0.0001); ③ SPTSM could significantly decrease total symptom scores with substantial effectiveness (P < 0.00001). The recurrence rate and adverse effects of SNZJD treatment were significantly reduced (P < 0.05). TSA showed that the effective rate of meta-analysis might be reliable, but the recurrence and safety results were still uncertain. According to the evaluation by the GRADE method, the quality of evidence was low. Besides, SNZJD might treat GERD by acting on related targets and pathways such as inflammation, hormone regulation, and so on.

Conclusions

SNZJD might be useful in the treatment of GERD, but its long-term effects and specific clinical mechanisms are unclear. Due to the poor quality of the evidence, more samples and high-quality clinical studies should be tested and verified in the future.