Normal values of pharyngeal and esophageal 24-hour pH impedance in individuals on and off therapy and interobserver reproducibility

Increased proximal acid reflux is associated with early readmission following lung transplantation

BACKGROUND

Gastroesophageal reflux disease has been associated with poor outcomes following lung transplantation. However, the association between pretransplant reflux and post-transplant readmission, an indicator of early clinical outcome, has not been previously assessed.

METHODS

This was a retrospective cohort study of lung transplant recipients undergoing pretransplant multichannel intraluminal impedance and pH (MII-pH) study off acid suppression at a tertiary care center since 2007. Subjects with pretransplant fundoplication were excluded. Time to readmission was defined as duration from post-transplant discharge to next hospital admission for any reason. Subgroup analysis was performed to exclude elective readmissions. Time-to-event analysis was performed using Cox proportional hazards model, with appropriate censoring.

KEY RESULTS

Forty-three subjects (60% men, mean age: 57, median follow-up: 1.7 years) met inclusion criteria for the study. Patient demographics and pretransplant cardiopulmonary function were similar between readmission cohorts. Time to all-cause readmission was associated with increased distal acid episodes (HR: 3.15, p = 0.04) and proximal acid episodes (HR: 3.61, p = 0.008) on impedance, increased acid exposure on pH (HR: 2.22, p = 0.04), and elevated Demeester score (HR: 2.26, p = 0.03). When elective readmissions were excluded, early readmission remained significantly associated with increased proximal acid reflux episodes (HR: 2.49, p = 0.04). All findings were confirmed on Kaplan-Meier analysis.

CONCLUSIONS & INFERENCES

Elevated proximal acid reflux on pretransplant MII-pH testing was associated with early readmission following lung transplantation, even after excluding elective readmissions. Exposure to severe acid reflux has measurable effects on early postoperative outcomes such as readmission, and aggressive early antireflux therapy should be considered.

Gastro-esophageal reflux and antisecretory drugs use among patients with chronic autoimmune atrophic gastritis: a study with pH-impedance monitoring

BACKGROUND

Patients with chronic autoimmune atrophic gastritis (CAAG) often refer digestive symptoms and are prescribed antisecretory medications. Aims were to investigate: (i) gastro-esophageal reflux (GER), (ii) psychopathological profile, (iii) frequency of use and clinical benefit of antisecretory drugs.

METHODS

Prospective observational study on 41 CAAG patients who underwent: 24 h multichannel intra-luminal impedance-pH (MII-pH) monitoring off-therapy, standardized medical interview and psychological questionnaire (i.e., SCL-90R). The medical interview was repeated at least 1 month after MII-pH in patients who were using antisecretory drugs. Statistical analysis was performed calculating median (10th-90th percentiles) and risk ratios (RR) with 95% confidence interval.

KEY RESULTS

Median intra-gastric pH was 6.2 (4.6-7.0). One patient had acid reflux (AC) associated with symptoms, five had increased total reflux number and four had symptoms associated to non-acid reflux (NA) (patients referred as 'GER positive'). Using patients 'GER negative' with normal SCL-90R as reference, the RR of being symptomatic in patients GER positive was 2.1 (1.1-4.1) if SCL-90R was normal and 0.9 (0.5-1.7) if it was altered (difference in RR significant being p = 0.04). Seventeen/28 (61%) symptomatic patients were on antisecretory drugs, which were stopped in 16 of them according to results of MII-pH and clinical evaluation after 574 days (48-796) showed that symptoms were unchanged.

CONCLUSIONS & INFERENCES

In patients with CAAG (i) AC reflux rarely occurred whereas increased NA reflux was not infrequent both being related to symptoms in some patients, (ii) psychopathological profile has a role in symptoms' occurrence, (iii) antisecretory drugs were generally inappropriately used and clinically ineffective.

Tailored therapy for the refractory GERD patients by combined multichannel intraluminal impedance-pH monitoring

BACKGROUND AND AIMS

About 30% of patients with gastroesophageal reflux disease (GERD) are refractory to proton pump inhibitor (PPI). The reason for the PPI failure in Asian GERD patients has rarely been studied, and the therapy remained unclear. The aims were to explore the possible reasons for PPI failure and to treat these patients with the guidance of 24-h multichannel intraluminal impedance-pH (MII-pH) monitoring.

METHODS

Thirty-nine consecutive patients with refractory GERD were enrolled; 24-h MII-pH monitoring was performed on PPI. The refractory GERD patients were grouped into acid overexposure, non-acid reflux, and functional heartburn after the MII-pH monitoring. Double dose of either PPI or paroxetine was administered to refractory GERD patients within different groups.

RESULTS

The number of patients in groups of acid overexposure, non-acid reflux, and functional heartburn was 6, 12, and 21, respectively. The acid overexposure group had the most acid reflux events. Among the acid overexposure group, five (5/6) patients accomplish symptom relief with double dose of esomeprazole. For the patients in non-acid reflux group, double dose of esomeprazole made half (6/12) of the patients obtain symptom relief. For the patients in functional heartburn group, the paroxetine had relieved the symptoms in 14 patients among all the 21 patients. In total, with the guidance of MII-pH monitoring, 64.1% (25/39) of refractory GERD patients accomplished symptom relief.

CONCLUSIONS

Acid overexposure, non-acid reflux, and functional heartburn were the common reasons for persistent reflux symptoms despite PPI. With the guidance of MII-pH, a tailored therapy could resolve the persistent reflux symptoms among two-third of patients.

24-hour pH-impedance monitoring on therapy to select patients with refractory reflux symptoms for antireflux surgery. A single center retrospective study

BACKGROUND

Treatment of gastro-esophageal reflux refractory symptoms is challenging. This monocenter retrospective study assessed the value of preoperative pH-impedance monitoring 'on' therapy to predict functional outcome after laparoscopic fundoplication in patients with refractory reflux symptoms.

METHODS

Patients with a preoperative pH-impedance monitoring 'on' proton pump inhibitors (PPIs) twice daily were assessed at least 6 months after a laparoscopic fundoplication for refractory reflux symptoms. Failure of fundoplication was defined by a Visick score > 2. Postoperative symptoms were assessed by the reflux disease questionnaire (RDQ). The pH-impedance parameters analyzed were the number of reflux events (total, acid, non-acid), esophageal acid exposure time, esophageal bolus exposure time, and symptom-reflux association defined by symptom index (SI) >50% and symptom association probability (SAP) >95%.

KEY RESULTS

Thirty-three patients (18 female patients, median age 46 years) were assessed after a mean follow-up of 41.3 (range 7-102.2) months. Seven (21.2%) patients were considered as failures. Compared to patients with favorable outcome, these patients were more often 'on' PPI therapy (86% vs 23%, p < 0.05) and had higher RDQ scores in each domain: heartburn (p < 0.05), regurgitation (p < 0.05) and dyspepsia (p < 0.05). A positive SAP was the only pH-impedance parameter statistically associated with successful postoperative outcome (p = 0.004).

CONCLUSIONS & INFERENCES

On therapy, a preoperative positive symptom association probability is the only pH-impedance parameter associated with favorable outcome after laparoscopic fundoplication for refractory reflux symptoms. These results should be confirmed by prospective studies.

Idiopathic pulmonary fibrosis is associated with increased impedance measures of reflux compared to non-fibrotic disease among pre-lung transplant patients

BACKGROUND

Gastroesophageal reflux (GER) has been associated with idiopathic pulmonary fibrosis (IPF), although the mechanism remains unclear. Gastroesophageal reflux/microaspiration may lead to lung fibrosis, while increased pulmonary workload may also worsen GER. Comparing the GER profile of IPF patients to chronic obstructive pulmonary disease (COPD) patients with similar lung function may help delineate the role of GER in IPF pathogenesis.

METHODS

This was a retrospective cohort study of IPF and COPD patients undergoing pre-lung transplant multichannel intraluminal impedance and pH study (MII-pH) off acid suppression at a tertiary center in 2008-2014. Patients with prior fundoplication were excluded. Baseline demographics, pulmonary function test, and MII-pH results were recorded. Univariate analyses were performed using Fisher's exact (binary variables) and Student's t (continuous variables) tests. Logistic regression was performed to adjust for potential confounders.

KEY RESULTS

A total of 90 subjects (54 IPF, 36 COPD) met inclusion criteria. Compared to COPD, IPF patients had increased total reflux episodes (65.9 vs 46.1, p = 0.02), proximal reflux episodes (30.3 vs 20.3, p = 0.04), and prevalence of abnormal total reflux episodes (38.9% vs 16.7%, p = 0.02). On multivariate analyses, abnormal total reflux episodes (OR: 4.9, p = 0.05) and bolus reflux exposure time (OR: 4, p = 0.04) remained significantly associated with IPF.

CONCLUSIONS & INFERENCES

Abnormal reflux was significantly more prevalent among IPF patients after controlling for lung disease severity. Gastroesophageal reflux/microaspiration likely plays a role in fibrosis in IPF. A significant portion of IPF patients had increased non-acid reflux. Therapies aiming to prevent reflux of gastric contents may be more beneficial than antisecretory medications alone in these patients.

Influence of reflux and central obesity on intercellular space diameter of esophageal squamous epithelium

BACKGROUND

While central obesity increases gastroesophageal reflux (GER) by mechanically disrupting the anti-reflux barrier, limited data exist on pathways by which central obesity may potentiate esophageal injury by non-mechanical means. Obesity has been associated with an impaired epithelial intestinal barrier.

OBJECTIVE

We aimed to assess the influence of central obesity and reflux on the squamous esophageal epithelial intercellular space diameter (ICSD).

METHODS

The ICSD was measured using electron microscopy in esophageal biopsies from individuals who underwent ambulatory pH monitoring and endoscopy. Anthropometric measurements were obtained on all participants. Participants were classified into four groups: with and without central obesity and reflux.

RESULTS

Sixteen individuals were studied with four in each study group. The mean ICSD was almost three-fold greater (p < 0.001) in the group with central obesity without reflux, compared to controls without central obesity and reflux. It was also comparable to the ICSD in groups with acid reflux only and those with both reflux and central obesity.

CONCLUSIONS

There is evidence of esophageal squamous ICSD increase in individuals with central obesity who do not have evidence of acid and nonacid reflux on ambulatory pH monitoring. This may reflect a mechanism by which central obesity potentiates reflux-induced esophageal injury and inflammation.

An expert panel-based study on recognition of gastro-esophageal reflux in difficult esophageal pH-impedance tracings

BACKGROUND

Despite existing criteria for scoring gastro-esophageal reflux (GER) in esophageal multichannel pH-impedance measurement (pH-I) tracings, inter- and intra-rater variability is large and agreement with automated analysis is poor. To identify parameters of difficult to analyze pH-I patterns and combine these into a statistical model that can identify GER episodes with an international consensus as gold standard.

METHODS

Twenty-one experts from 10 countries were asked to mark GER presence for adult and pediatric pH-I patterns in an online pre-assessment. During a consensus meeting, experts voted on patterns not reaching majority consensus (>70% agreement). Agreement was calculated between raters, between consensus and individual raters, and between consensus and software generated automated analysis. With eight selected parameters, multiple logistic regression analysis was performed to describe an algorithm sensitive and specific for detection of GER.

KEY RESULTS

Majority consensus was reached for 35/79 episodes in the online pre-assessment (interrater κ = 0.332). Mean agreement between pre-assessment scores and final consensus was moderate (κ = 0.466). Combining eight pH-I parameters did not result in a statistically significant model able to identify presence of GER. Recognizing a pattern as retrograde is the best indicator of GER, with 100% sensitivity and 81% specificity with expert consensus as gold standard.

CONCLUSIONS & INFERENCES

Agreement between experts scoring difficult impedance patterns for presence or absence of GER is poor. Combining several characteristics into a statistical model did not improve diagnostic accuracy. Only the parameter 'retrograde propagation pattern' is an indicator of GER in difficult pH-I patterns.

Gastroesophageal reflux in asymptomatic obese subjects: An esophageal impedance-pH study

AIM

To investigate the relationship between reflux and body mass index (BMI) in the asymptomatic obese population using the impedance-pH technique.

METHODS

Gastroesophageal reflux is frequent in the obese population. However, the relationship between acid reflux and BMI in asymptomatic obese people is unclear. Forty-six obese (BMI > 25 kg/m(2)) people were enrolled in this prospective study. We evaluated the demographic findings and 24-h impedance pH values of the whole group. Gas, acid (pH < 4), weak acid (pH = 4-7) and weak alkaline (pH ≥ 7) reflux parameters were analyzed.

RESULTS

The mean age of patients was 49.47 ± 12.24 years, and half of them were men. The mean BMI was 30.64 ± 3.95 kg/m(2) (25.14-45.58 kg/m(2)). BMI of 23 was over 30 kg/m(2). Seventeen patients had a comorbidity (hypertension, diabetes mellitus, or ischemic heart disease). Endoscopic examination revealed esophagitis in 13 of the 28 subjects (10 Grade A, 3 Grade B). The subjects were divided into two groups according to BMI (< 30 and > 30 kg/m(2)). Demographic and endoscopic findings, and impedance results were similar in these two groups. However, there was a positive correlation between BMI and total and supine pH < 4 episodes (P = 0.002, r = 0.414; P = 0.000, r = 0.542), pH < 4 reflux time (P = 0.015, r = 0.319; P = 0.003, r = 0.403), and DeMeester score (P = 0.012, r = 0.333).

CONCLUSION

Acid reflux is correlated with BMI in asymptomatic obese individuals.

Oesophageal function assessed by high-resolution manometry in patients with diabetes and inadequate glycaemic control

AIMS

To describe oesophageal function in people with diabetes and poor glycaemic control using oesophageal high-resolution manometry and to compare the result between control subjects and patients with gastro-oesophageal reflux disease.

METHODS

The results of oesophageal high-resolution manometry and a gastric emptying test were reviewed in 20 patients with diabetes. The high-resolution manometry protocol consisted of 5-ml swallows of water and multiple swallows of water. Oesophageal motility disorders were classified according to the Chicago classification system. The occurence of multiphasic contractions and intragastric and intrabolus pressures were measured. High-resolution manometry results were compared between 10 control subjects and 20 patients with gastro-oesophageal reflux disease. Data were expressed as medians and compared using Mann-Whitney and chi-squared tests.

RESULTS

Oesophageal motility disorders were similarly distributed between the groups. Multiphasic contractions occurred more frequently in patients with diabetes than in those with gastro-oesophageal reflux disease (60 vs 20% per patient; P<0.01) and were not observed in control subjects. Gastric emptying was delayed in six patients with diabetes and did not correlate with symptoms or oesophageal motility disorders. Intrabolus pressure was higher in patients with diabetes and gastroparesis than in those without (17 vs 10 mmHg; P=0.02) and correlated with intragastric pressure (r=0.46, P<0.01). During multiple swallows of water, oesophageal contractile activity was incompletely inhibited in 83% of patients with diabetes and gastroparesis vs 9% without (P<0.01). Oesophageal function and gastric emptying were not influenced by fasting glycaemia.

CONCLUSIONS

Patients with gastroparesis might present with impaired inhibition of contractile activity during multiple swallows of water. Increased intrabolus pressure is suggestive of delayed oesophageal clearance as a consequence of gastroparesis.

Diagnostic Utility of Impedance-pH Monitoring in Refractory Non-erosive Reflux Disease

Background/Aims

Approximately one-third of non-erosive reflux disease (NERD) patients are refractory to proton pump inhibitors (PPI) and face a therapeutic challenge. Therefore, it is important to differentiate between pathological and non-pathological reflux utilizing multichannel intraluminal impedance-pH (MII-pH) to analyze symptom-reflux association and diagnose true NERD versus hyper-sensitive esophagus (HE) and functional heartburn (FH). Herein, we evaluated the diagnostic yield of MII-pH in refractory NERD and sub-classified it based on quantity and quality of acid/non-acid reflux and reflux-symptom association.

Methods

Sixty symptomatic NERD patients on twice daily PPI for > 2 months were prospectively evaluated by MII-pH. Distal and proximal refluxes, bolus exposure time (BET), esophageal acid exposure time, symptom index (SI) and symptom association probability (SAP) were measured.

Results

Thirty-two (53%) patients had BET > 1.4% (MII-pH positive-true NERD), while 28 (47%) had BET < 1.4% (MII-pH negative NERD) where SI and SAP were negative in 15/60 (25%; categorized as FH) and SI or SAP were positive in 13/60 (22%; identified as HE). Thirty-eight (63%) patients reported significant SI or SAP parameters where > 80% of symptoms were associated with non-acid reflux. The number of distal refluxes in true NERD versus FH or HE were significantly different, but not between FH and HE.

Conclusions

Approximately 60% of refractory PPI NERD patients had positive reflux-symptom association, primarily due to non-acid reflux. Nearly half of NERD patients on PPI had normal MII-pH monitoring, sub-divided further into FH and HE equally.

Pre-transplant impedance measures of reflux are associated with early allograft injury after lung transplantation

BACKGROUND

Acid reflux has been associated with poorer outcomes after lung transplantation. Standard pre-transplant reflux assessment has not been universally adopted. Non-acid reflux may also induce a pulmonary inflammatory cascade, leading to acute and chronic rejection. Esophageal multichannel intraluminal impedance and pH testing (MII-pH) may be valuable in standard pre-transplant evaluation. We assessed the association between pre-transplant MII-pH measures and early allograft injury in lung transplant patients.

METHODS

This was a retrospective cohort study of lung transplant recipients who underwent pre-transplant MII-pH at a tertiary center from 2007 to 2012. Results from pre-transplant MII-pH, cardiopulmonary function testing, and results of biopsy specimen analysis of the transplanted lung were recorded. Time-to-event analyses were performed using Cox proportional hazards and Kaplan-Maier methods to assess the associations between MII-pH measures and development of acute rejection or lymphocytic bronchiolitis.

RESULTS

Thirty patients (46.7% men; age, 54.2 years) met the inclusion criteria. Pre-transplant cardiopulmonary function and pulmonary diagnoses were similar between outcome groups. Prolonged bolus clearance (hazard ratio [HR], 4.11; 95% confidence interval [CI], 1.34-12.57; p = 0.01), increased total distal reflux episodes (HR, 4.80; 95% CI, 1.33-17.25; p = 0.02), and increased total proximal reflux episodes (HR, 4.43; 95% CI, 1.14-17.31; p = 0.03) were significantly associated with decreased time to early allograft injury. Kaplan-Meier curves also demonstrated differences in time to rejection by prolonged bolus clearance (p = 0.01) and increased total distal reflux episodes (p = 0.01). Sub-group analysis including only patients with MII-pH performed off proton pump inhibitors (n = 24) showed similar results.

CONCLUSIONS

Prolonged bolus clearance, increased total distal reflux episodes, and increased total proximal reflux episodes on pre-transplant MII-pH were associated with decreased time to early allograft injury after lung transplantation. Routine pre-transplant MII-pH may provide clinically relevant data regarding transplant outcomes and peri-transplant care.

Development of the reflux finding score for infants and its observer agreement

OBJECTIVE

It is hypothesized that laryngeal edema is caused by laryngopharyngeal reflux (LPR) (ie, gastroesophageal reflux extending into the larynx and pharynx). The validated reflux finding score (RFS) assesses LPR disease in adults. We, therefore, aimed to develop an adapted RFS for infants (RFS-I) and assess its observer agreement.

STUDY DESIGN

Visibility of laryngeal anatomic landmarks was assessed by determining observer agreement. The RFS-I was developed based on the RFS, the found observer agreement, and expert opinion. An educational tutorial was developed which was presented to 3 pediatric otorhinolaryngologists, 2 otorhinolaryngologists, and 2 gastroenterology fellows. They then scored videos of flexible laryngoscopy procedures of infants who were either diagnosed with or specifically without laryngeal edema.

RESULTS

In total, 52 infants were included with a median age of 19.5 (0-70) weeks, with 12 and 40 infants, respectively, for the assessment of the laryngeal anatomic landmarks and the assessment of the RFS-I. Overall interobserver agreement of the RFS-I was moderate (intraclass correlation coefficient = 0.45). Intraobserver agreement ranged from moderate to excellent agreement (intraclass correlation coefficient = 0.50-0.87).

CONCLUSION

A standardized scoring instrument was developed for the diagnosis of LPR disease using flexible laryngoscopy. Using this tool, only moderate interobserver agreement was reached with a highly variable intraobserver agreement. Because a valid scoring system for flexible laryngoscopy is lacking up until now, the RFS-I and flexible laryngoscopy should not be used solely to clinically assess LPR related findings of the larynx, nor to guide treatment.

Hypopharyngeal pepsin and Sep70 as diagnostic markers of laryngopharyngeal reflux: preliminary study

INTRODUCTION

The management of laryngopharyngeal reflux (LPR) has been challenging. Hypopharyngeal multichannel intraluminal impedance (HMII) has shown to increase the sensitivity in diagnosing LPR. The objective of this study is to investigate the potential use of pepsin and Sep70 as diagnostic tools for detection of LPR in combination with HMII.

MATERIALS AND METHODS

Tissue samples of hypopharynx, distal esophagus, and gastric cardia were collected from patients with LPR symptoms regardless of gastroesophageal reflux (GERD) diagnosis and underwent HMII to detect LPR and high esophageal reflux (HER: reflux 2 cm distal to upper esophageal sphincter) events. Patients were classified into two groups based on the presence of abnormal proximal exposure (APE), which was defined as LPR ≥1/day and/or HER ≥5/day: (1) positive-APE and (2) negative-APE. Patients with typical GERD symptoms without LPR symptoms who did not undergo HMII were used as a "control" GERD group. Protein was isolated from tissue samples and Western blot analysis of pepsin and Sep70 was performed. Pepsinogen was used as a control to differentiate pepsin from pepsinogen. Relative quantitation was performed using Image Studio Lite Software with normalization against the internal actin of each blot.

RESULTS

From October 2012 to September 2013, 55 patients underwent HMII. Of 55, 20 patients underwent biopsies from hypopharynx (17 positive-APE and 3 negative-APE). Ten patients with typical GERD symptoms were identified from tissue bank as a "control" GERD group. Pepsin was detected in distal esophagus and hypopharynx in all groups without significant difference among groups. However, Sep70 in distal esophagus and hypopharynx was significantly depleted in the positive-APE group compared to the other groups (p = 0.032 and 0.002, respectively).

CONCLUSION

Depletion of Sep70 with the presence of pepsin in the hypopharynx may indicate cellular injury in laryngopharynx due to constant proximal reflux. However, the normative data for these markers have to be validated.

Modern medical and surgical management of difficult-to-treat GORD

Approximately 30-40% of patients taking proton pump inhibitors (PPIs) for presumed gastro-oesophageal reflux (GOR) symptoms do not achieve adequate symptom control, especially when no oesophageal mucosal breaks are present at endoscopy and when extra-oesophageal symptoms are concerned. After failure of optimization of medical therapy, a careful work up is mandatory that aims at determining whether symptoms are related to GOR or not. Most patients with refractory symptoms do not have GOR-related symptoms. Some may have symptoms related to weakly acidic reflux and/or oesophageal hypersensitivity. Baclofen is currently the only antireflux compound available as add-on therapy to PPIs, but its poor tolerability limits its use in clinical practice. There is room for pain modulators in patients with hypersensitive oesophagus and functional heartburn. Antireflux surgery is a suitable option in patients responding to medical therapy who want to avoid taking medication or if persisting symptoms can be clearly attributed to poorly controlled GOR.

Pharyngeal pH alone is not reliable for the detection of pharyngeal reflux events: A study with oesophageal and pharyngeal pH-impedance monitoring

BACKGROUND

Pharyngeal pH probes and pH-impedance catheters have been developed for the diagnosis of laryngo-pharyngeal reflux.

OBJECTIVE

To determine the reliability of pharyngeal pH alone for the detection of pharyngeal reflux events.

METHODS

24-h pH-impedance recordings performed in 45 healthy subjects with a bifurcated probe for detection of pharyngeal and oesophageal reflux events were reviewed. Pharyngeal pH drops to below 4 and 5 were analysed for the simultaneous occurrence of pharyngeal reflux, gastro-oesophageal reflux, and swallows, according to impedance patterns.

RESULTS

Only 7.0% of pharyngeal pH drops to below 5 identified with impedance corresponded to pharyngeal reflux, while 92.6% were related to swallows and 10.2 and 13.3% were associated with proximal and distal gastro-oesophageal reflux events, respectively. Of pharyngeal pH drops to below 4, 13.2% were related to pharyngeal reflux, 87.5% were related to swallows, and 18.1 and 21.5% were associated with proximal and distal gastro-oesophageal reflux events, respectively.

CONCLUSIONS

This study demonstrates that pharyngeal pH alone is not reliable for the detection of pharyngeal reflux and that adding distal oesophageal pH analysis is not helpful. The only reliable analysis should take into account impedance patterns demonstrating the presence of pharyngeal reflux event preceded by a distal and proximal reflux event within the oesophagus.

Acid-based parameters on pH-impedance testing predict symptom improvement with medical management better than impedance parameters

OBJECTIVES

pH-impedance testing detects reflux events irrespective of pH, but its value in predicting treatment outcome is unclear. We prospectively evaluated subjects treated medically after pH-impedance testing to determine predictors of symptom improvement.

METHODS

Subjects referred for pH-impedance testing completed questionnaires in which dominant symptoms and global symptom severity (GSS) were recorded. Acid-reflux parameters (acid-exposure time, AET; symptom association by Ghillebert probability estimate, GPE; symptom index, SI) and impedance reflux parameters (reflux-exposure time, RET; number of reflux events; GPE and SI with impedance data) were extracted. Symptoms and GSS were prospectively reevaluated after medical therapy. Univariate and multivariate analyses determined predictors of GSS improvement following medical management.

RESULTS

Over 5 years, 128 subjects (mean 53.3±1.3 years, 66.4% female; typical symptoms 57.0%, 53.9% tested on therapy) underwent pH-impedance testing and subsequent medical therapy for reflux symptoms, and completed required questionnaires. On follow-up 3.35±0.14 years later, mean GSS declined by 45.0%, with 42.2% patients reporting ≥50% GSS improvement. On univariate analysis, total AET, AET≥4.0%, and GPE for all reflux events predicted both linear and ≥50% GSS improvement, but RET and number of reflux events did not. On multivariate analysis, controlling for testing on or off therapy, only AET (P=0.003) and GPE for all reflux events (P=0.029) predicted GSS improvement.

CONCLUSIONS

Acid-based reflux parameters offer greater value over impedance-based nonacid-reflux parameters in predicting symptomatic responses to proton pump inhibitor (PPI) therapy. Our findings support conducting pH-impedance studies off PPI therapy to maximize clinical utility in predicting outcome.

Impedance pH Monitoring: Intra-observer and Inter-observer Agreement and Usefulness of a Rapid Analysis of Symptom Reflux Association

BACKGROUND/AIMS

Symptom reflux association analysis is especially helpful for evaluation and management of proton pump inhibitor (PPI) re-fractory patients. An accurate calculation requires manual editing of 24-hour multichannel intraluminal impedance-pH (MII-pH) tracings after automatic analysis. Intra- and inter-observer agreement as well as reliability of rapid editing confined to the time around symptomatic episodes are unknown. Aim of this study was to explore these topics in a prospective multicenter study.

METHODS

Forty consecutive patients who were off PPI therapy underwent MII-pH recordings. After automatic analysis, their tracings were anonymized and randomized. Three experienced observers, each one trained in a different European center, independently per-formed manual editing of 24-hour tracings on 2 separate occasions. Values of symptom index and symptom association proba-bility for acid and non acid reflux were transformed into binary response (i.e., positive or negative).

RESULTS

Intra-observer agreement on symptom reflux association was 92.5% to 100.0% for acid and 85.0% to 97.5% for non-acid reflux. Inter-observer agreement was 100.0% for acid and 82.5% to 95.0% for non-acid reflux. Values for symptom index and symptom association probability were similar. Concordance between 24-hour and rapid (2 minutes-window before each symp-tomatic episode) editings for symptom reflux association occured in 39 to 40 patients (acid) and in 37 to 40 (non-acid), de-pending on the observer.

CONCLUSIONS

Intra- and inter-observer agreement in classifying patients with or without symptom reflux association at manual editing of 24-hour tracings was high, especially for acid reflux. Classifying patients according to a rapid editing showed excellent con-cordance with the 24-hour one and can be adopted in clinical practice.

Acid and nonacid reflux monitoring

Detection of acid and nonacid reflux using esophageal reflux monitoring, which includes conventional and wireless pH monitoring and pH impedance, can be a valuable diagnostic tool when used appropriately in the assessment of patients with gastroesophageal reflux disease. Reflux monitoring may be especially helpful if a management change is desired, such as when initial or empirical treatment is ineffective. However, each of these methods has its limitations, which need to be accounted for in their clinical use. Indications, test performance, interpretation, and clinical applications of esophageal reflux monitoring, as well as their limitations, are discussed in this review.

Early referral for esophageal pH monitoring is more cost-effective than prolonged empiric trials of proton-pump inhibitors for suspected gastroesophageal reflux disease

INTRODUCTION

The most cost-effective diagnostic algorithm for gastroesophageal reflux disease (GERD) remains controversial. We hypothesized that prompt referral for esophageal pH monitoring is more cost-effective than prolonged empiric courses of proton-pump inhibitors (PPIs).

DISCUSSION

A cost model was created based on a cohort of 100 patients with possible GERD who underwent pH monitoring. The additional costs incurred from pH monitoring were compared to the potential savings from avoiding unnecessary PPI usage in patients with a negative pH study. The costs of PPI therapy reach equivalence with pH monitoring after 6.4 to 23.7 weeks, depending on the PPI regimen. A total of 21,411 weeks of PPIs were prescribed beyond the recommended 8-week trial, of which 32 % were for patients who had a negative 24-h pH monitoring study. If the sensitivity of pH monitoring was 96 %, early referral for pH monitoring would have saved between $1,197 and $6,303 per patient over 10 years. This strategy remains cost-effective as long as the sensitivity of pH monitoring is above 35 %. Prompt referral for pH monitoring after a brief empiric PPI trial is a more cost-effective strategy than prolonged empiric PPI trials for patients with both esophageal and extraesophageal GERD symptoms.

Changing the paradigm for cough: does 'cough hypersensitivity' aid our understanding?

Chronic cough is a common reason for patients to seek medication attention. Over the last few decades, we have experienced significant clinical success by applying the paradigm of 'evaluating and treating the causes for chronic cough'. However, we still ask ourselves 'what underlies chronic cough. Indeed in a considerable proportion of patients cough is idiopathic, or unexplained despite vigorous evaluation. Commonly associated conditions such as rhinitis, eosinophilic bronchitis, asthma, or gastroesophageal acidic reflux may not be fundamental to cough, and thus may be triggers rather than causes. The cardinal feature of chronic cough is persistent upregulation the cough reflex, which may be driven by complex interactions between biologic, neurologic, immunologic, genetic, comorbid, and environmental factors. We suggest the new paradigm 'cough hypersensitivity syndrome' should finally bring us further advances in understanding and management of chronic cough.

Can multichannel intraluminal pH-impedance monitoring be limited to 3 hours? Comparison between ambulatory 24-hour and post-prandial 3-hour recording

Esophageal multichannel intraluminal pH-impedance recording (MII) is now a valid technique for determining the acidic, liquid, gas or mixed nature of gastroesophageal reflux episodes. However, some recordings may stop prematurely due to technical reasons or poor patient tolerance of the probe. Therefore, we questioned whether analysis of post-prandial 3-hour recording could predict the results obtained in ambulatory 24-hour recording. Fifty patients with symptoms of gastroesophageal reflux disease were investigated. For each patient, post-prandial 3-hour MII was recorded after a test meal, then followed by ambulatory 21-hour MII. Correlation between the total number of liquid reflux events in the 3-hour and 24-hour recordings was elevated (R=0.71; P<0.001), with better correlation for acid (R=0.80; P<0.001) and weak acid reflux (R=0.56; P<0.001) than non-acid reflux (R=0.44; P<0.01). Sensitivity and specificity of 3-hour recording in detecting elevated liquid reflux over 24 hours (id>75reflux/24 h) were 49% and 100%, respectively, for 8 or less liquid/mixed reflux events per 3 hours, and 78% and 88%, respectively for 15 or more liquid/mixed reflux events per 3 hours. The sensitivity and specificity of symptom association probability (SAP) calculated over 3 hours were 56% and 91%, respectively. In conclusion, we identified relevant indicators on the 3-hour post-prandial recording likely to give accurate prediction of absence or presence of gastroesophageal reflux disease from 24-hour MII recording.

A causal relationship between cough and gastroesophageal reflux disease (GERD) has been established: a pro/con debate

Along with upper airway cough syndrome (formerly, postnasal drip syndrome) and eosinophilic airway inflammation (asthma, nonasthmatic eosinophilic bronchitis), gastroesophageal reflux disease (GERD) is generally considered among the most common etiologies of chronic cough. Indeed, cough management guidelines published by numerous respiratory societies worldwide recommend evaluation and treatment of GERD as an integral component of the diagnostic/therapeutic algorithm for the management of chronic cough. However, a significant number of patients with chronic cough presumed due to GERD do not report improvement despite aggressive acid-suppressive therapy. Some of these refractory cases may be due to the recently appreciated entity of nonacid or weakly acidic reflux. Further contributing to the controversy are recent studies that demonstrate that patients with chronic cough do not have excessive reflux events relative to healthy volunteers. Although a temporal relationship between cough and reflux events has been suggested by studies utilizing impedance-pH monitoring of reflux events and objective cough recording, consensus is lacking in terms of whether this temporal relationship proves a causal link between reflux and cough. The fourth American Cough Conference (New York, June 2013) provided an ideal forum for the debate of this issue between two internationally recognized experts in the field of reflux and chronic cough.

Preoperative diagnostic workup before antireflux surgery: an evidence and experience-based consensus of the Esophageal Diagnostic Advisory Panel

BACKGROUND

Gastroesophageal reflux disease (GERD) is a very prevalent disorder. Medical therapy improves symptoms in some but not all patients. Antireflux surgery is an excellent option for patients with persistent symptoms such as regurgitation, as well as for those with complete symptomatic resolution on acid-suppressive therapy. However, proper patient selection is critical to achieve excellent outcomes.

STUDY DESIGN

A panel of experts was assembled to review data and personal experience with regard to appropriate preoperative evaluation for antireflux surgery and to construct an evidence and experience-based consensus that has practical application.

RESULTS

The presence of reflux symptoms alone is not sufficient to support a diagnosis of GERD before antireflux surgery. Esophageal objective testing is required to physiologically and anatomically evaluate the presence and severity of GERD in all patients being considered for surgical intervention. It is critical to document the presence of abnormal distal esophageal acid exposure, especially when antireflux surgery is considered, and reflux-related symptoms should be severe enough to outweigh the potential side effects of fundoplication. Each testing modality has a specific role in the diagnosis and workup of GERD, and no single test alone can provide the entire clinical picture. Results of testing are combined to document the presence and extent of the disease and assist in planning the operative approach.

CONCLUSIONS

Currently, upper endoscopy, barium esophagram, pH testing, and manometry are required for preoperative workup for antireflux surgery. Additional studies with long-term follow-up are required to evaluate the diagnostic and therapeutic benefit of new technologies, such as oropharyngeal pH testing, multichannel intraluminal impedance, and hypopharyngeal multichannel intraluminal impedance, in the context of patient selection for antireflux surgery.

Approach to the patient with presumed extraoesophageal GERD

Reflux related cough, asthma and laryngitis are frequently encountered and are considered part of extraoesophageal syndromes. The diagnosis of extraoesophageal reflux is difficult due to the lack of gold standard diagnostic criteria. Esophagogastroduodenoscopy and esophageal pH monitoring are inadequate diagnostic tools for due to poor sensitivity and specificity. For this reason, empirical PPI therapy is recommended as an initial approach to diagnose and treat the potential underlying cause of these symptoms in patients without alarm symptoms. Diagnostic testing with esophageal pH and/or impedance monitoring and esophageal motility testing is usually reserved for those who continue to be symptomatic despite a trial of therapy with PPIs. Recent developments have increased our understanding of this difficult to treat group of patients but more research into reflux related extraoesophageal symptoms are needed to better diagnose and treat this group.

The oesophagus and cough: laryngo-pharyngeal reflux, microaspiration and vagal reflexes

Gastro-oesophageal reflux disease is generally considered to be one of the commonest causes of chronic cough, however randomised controlled trials of proton pump inhibitors have often failed to support this notion. This article reviews the most recent studies investigating the mechanisms thought to link reflux and cough, namely laryngo-pharyngeal reflux, micro-aspiration and neuronal cross-organ sensitisation. How recent evidence might shed light on the failure of acid suppressing therapies and suggest new approaches to treating reflux related cough are also discussed.