Reproducibility of meal-induced transient lower oesophageal sphincter relaxations in patients with gastro-oesophageal reflux disease

Modern diagnosis of GERD: the Lyon Consensus

Clinical history, questionnaire data and response to antisecretory therapy are insufficient to make a conclusive diagnosis of GERD in isolation, but are of value in determining need for further investigation. Conclusive evidence for reflux on oesophageal testing include advanced grade erosive oesophagitis (LA grades C and D), long-segment Barrett's mucosa or peptic strictures on endoscopy or distal oesophageal acid exposure time (AET) >6% on ambulatory pH or pH-impedance monitoring. A normal endoscopy does not exclude GERD, but provides supportive evidence refuting GERD in conjunction with distal AET <4% and <40 reflux episodes on pH-impedance monitoring off proton pump inhibitors. Reflux-symptom association on ambulatory reflux monitoring provides supportive evidence for reflux triggered symptoms, and may predict a better treatment outcome when present. When endoscopy and pH or pH-impedance monitoring are inconclusive, adjunctive evidence from biopsy findings (histopathology scores, dilated intercellular spaces), motor evaluation (hypotensive lower oesophageal sphincter, hiatus hernia and oesophageal body hypomotility on high-resolution manometry) and novel impedance metrics (baseline impedance, postreflux swallow-induced peristaltic wave index) can add confidence for a GERD diagnosis; however, diagnosis cannot be based on these findings alone. An assessment of anatomy, motor function, reflux burden and symptomatic phenotype will therefore help direct management. Future GERD management strategies should focus on defining individual patient phenotypes based on the level of refluxate exposure, mechanism of reflux, efficacy of clearance, underlying anatomy of the oesophagogastric junction and psychometrics defining symptomatic presentations.

Objective definition and detection of transient lower esophageal sphincter relaxation revisited: is there room for improvement?

BACKGROUND

The advent of drugs that inhibit transient lower esophageal sphincter relaxation (TLESR) necessitates accurate identification and scoring. We assessed the intra- and inter-assessor variability of the existing objective criteria for TLESR, improving them where necessary.

METHODS

Two 3-h postprandial esophageal manometric and pH recordings were performed in 20 healthy volunteers. Each recording was duplicated. The recordings were analyzed by five experienced observers for TLESRs based on their expert opinion. TLESRs were also analyzed for the presence of the original four criteria as well as inhibition of the crural diaphragm (ID), a prominent after-contraction (AC), acid reflux and an esophageal common cavity.

KEY RESULTS

The overall inter- and intra-observer agreements for TLESRs scored, according to observer's expert opinion, were 59% (range 56-67%) and 74% (60-89%), respectively. When TLESRs were restricted to those fulfilling the original criteria, these agreements fell to 46% (40-53%) and 60% (44-67%), respectively. Cleaning the recordings by removal of technically flawed sections improved agreements by 5%. Inclusion of additional criteria (ID and AC) resulted in inter- and intra-observer agreements of 62% (52-70%) and 69% (53-79%), respectively. A consensus analysis performed collectively by three observers and based on the new criteria (original ± ID and AC) resulted in 84% agreement between the paired recordings.

CONCLUSIONS & INFERENCES

The original criteria for the definition of TLESRs allows for substantial inter- and intra-observer variability, which can be reduced by incorporation of additional objective criteria. However, the highest level of intra-observer agreement can be achieved by consensus analysis.

Efficacy, tolerability and pharmacokinetics of a modified release formulation of ADX10059, a negative allosteric modulator of metabotropic glutamate receptor 5: an esophageal pH-impedance study in healthy subjects

BACKGROUND

Animal studies show metabotropic glutamate receptor 5 inhibition reduces transient lower esophageal sphincter relaxations and increases lower esophageal sphincter tone. A preliminary, single-day study, demonstrated oral ADX10059 reduced 24-h esophageal acid exposure and clinical symptoms in gastro-esophageal reflux disease (GERD) patients, but had suboptimal tolerability, ascribable to the compound's rapid absorption. This study evaluated ADX10059 modified-release (MR) formulation pharmacokinetics, tolerability, and pharmacodynamics.

METHODS

Randomized, double-blind placebo-controlled study. Three groups of eight healthy, male subjects received placebo (n = 2) or ADX10059 (n = 6) 50, 125 or 250 mg b.i.d. for 6 days. Esophageal pH-impedance was performed on day 1 and day 6 of treatment, for 1-h fasting and for 4 h post refluxogenic meal. Treatment effect was determined by Kruskall-Wallis test and placebo comparison by Wilcoxon rank sum.

KEY RESULTS

Following placebo, reflux episodes increased from day 1 to day 6. Significant treatment effect was seen for total esophageal acid exposure (P = 0.048) and postprandial number of weakly acidic reflux episodes (P = 0.041). Significant differences from placebo were seen for 125 mg b.i.d.; 250 mg b.i.d. was not more effective than 125 mg b.i.d. Twice daily ADX10059 MR gave satisfactory 24-h exposure and good tolerability.

CONCLUSIONS & INFERENCES

ADX10059 decreased reflux episodes in healthy subjects. The MR formulation is suitable for longer-term treatment to evaluate symptom control in GERD patients.

Reproducibility of symptom association analysis in ambulatory reflux monitoring

INTRODUCTION

The temporal relationship between reflux symptoms and reflux episodes during ambulatory reflux monitoring can be studied with symptom association analysis, and the strength of the relationship can be expressed using indices such as the SAP (symptom association probability), SI (symptom index), and SSI (symptom sensitivity index). The reproducibility of these indices has not been determined yet.

METHOD

Twenty-one patients with typical reflux symptoms (9 men, 53 [38-57] yr) underwent two 24-h combined pH-impedance recordings off acid-secretory medication with an interval of 1-4 wk. The SAP, SI, and SSI were calculated for each measurement. Reproducibility of these indices was determined with Kendall's coefficients of concordance.

RESULTS

The number of reflux events were highly reproducible (Kendall W = 0.92, P < 0.01). The number of symptoms related to reflux events was reproducible (Kendall W = 0.91, P < 0.01) while the number of reported reflux symptoms was not (Kendall W = 0.75, P= 0.07). The SAP and SSI were highly reproducible (Kendall W = 0.90, P= 0.01, and W = 0.86, P < 0.05, respectively) but the SI was not (W = 0.73, P= 0.09). The percentage of patients with similar outcomes on two separate test days for the SAP, SI, and SSI was 86%, 67%, and 86%, respectively.

DISCUSSION

In 24-h pH-impedance recordings of patients with reflux symptoms, the number of reflux events and the number of symptoms related to reflux events were highly reproducible as were the SAP and SSI. This supports the use of these indices to express the relationship between symptoms and reflux episodes in clinical practice.

Expression of inducible heme oxygenase-1 in the patiant's mucous membrane of esophagus of reflux esophagitis

AIM: To detect the expression of heme oxygenase-1 (HO-1) in human esophageal mucosa with reflux esophagitis (RE), and to find out the role of gas messenger molecule carbon monoxide (CO) in the pathogenesis of RE.

METHODS: The distributions of HO-1 protein in the esophageal tissues of 77 RE cases and 20 normal controls were detected by immunohistochemistry (SP method).

RESULTS: HO-1 was expressed mainly in the esophageal mucosal epithelium. The expression of HO-1 in RE patients was significantly higher than that in the normal controls (0.2334 ± 0.0511 vs 0.1776 ± 0.0164, P < 0.01).

CONCLUSION: Abnormal expression of HO-1 exists in RE, suggesting that CO may play an important role in the pathogenesis of gastrointestinal motility disorders such as RE.

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