Proximal oesophagus: the added value in understanding GORD symptoms

Determinants of reflux perception in patients with non-erosive reflux disease who have reflux-related symptoms on potassium-competitive acid blocker therapy

BACKGROUND

This study investigated potential determinants of reflux perception in patients with non-erosive reflux disease (NERD) who had reflux-related symptoms on potassium-competitive acid blocker (P-CAB) therapy.

METHODS

This study included 23 patients with reflux-related symptoms despite P-CAB therapy. Esophageal impedance-pH monitoring was performed on P-CAB and the following potential determinants of reflux perception were investigated: reflux nadir pH value; change in pH (baseline-nadir); bolus clearance time; reflux extent; proportions of acid, weakly acidic, and weakly alkaline reflux episodes; and proportions of liquid and mixed reflux episodes.

RESULTS

Overall, ≥ 90% of all and symptomatic reflux episodes were weakly acidic reflux and 63% of symptomatic reflux episodes were reflux episodes with pH ≥ 5. There were no significant differences regarding potential determinants between symptomatic and asymptomatic reflux episodes. However, the proportion of symptomatic reflux episodes was significantly greater with pH < 5 (13.8%) than with pH ≥ 5 (9.5%) (P = 0.0431). In reflux episodes with pH < 5, the proportion of symptomatic reflux episodes was significantly greater in proximal sites (20.6%) than in distal sites (10.6%) (P = 0.0178). Conversely, in reflux episodes with pH ≥ 5, there was no significant difference regarding reflux perception according to reflux extent (proximal: 9.6% vs. distal: 9.0%, P = 0.9337).

CONCLUSIONS

In patients with P-CAB-resistant NERD, reflux symptoms were mainly caused by reflux episodes with pH ≥ 5 on P-CAB therapy. The proportions of symptomatic reflux episodes among reflux sites differed according to reflux pH value; thus, the mechanisms of reflux perception may differ according to reflux pH value.

Reflux characteristics triggering post-reflux swallow-induced peristaltic wave (PSPW) in patients with GERD symptoms

BACKGROUND

Esophageal chemical clearance has been evaluated with the post-reflux swallow-induced peristaltic wave (PSPW) index. The factors triggering PSPW in Gastro-esophageal reflux disease (GERD) have not yet been investigated. This multicenter study was aimed at evaluating the characteristics of reflux episodes associated with PSPW occurrence in patients with typical GERD symptoms.

METHODS

Impedance-pH tracings from patients with typical reflux symptoms were analyzed. Sixteen healthy subjects were included for comparison. Multivariate analysis was performed to determine predictors of PSPW events.

KEY RESULTS

Impedance-pH tracings from 60 patients and 16 healthy subjects were evaluated. A total of 3454 refluxes were recorded. In patients, comparing reflux episodes followed with those not followed by a PSPW, significantly higher proportions of acid (79% vs. 74%, p: 0.02), mixed (47% vs. 32%, p: 0.0001) and proximal refluxes (34% vs. 20%, p: 0.0001) were observed. A multivariate analysis, acid (OR: 1.3, 95% CI: 1.05-1.6), mixed (OR: 2, 95% CI: 1.6-2.3), and proximal (OR: 2.1, 95% CI: 1.7-2.5) refluxes were independently associated with PSPWs. Reflux episodes followed by a PSPW were characterized by a significantly higher bolus clearing time [(mean ± SD) 41 s ± 6 s vs. 30 s ± 5 s, p < 0.05] whereas nadir pH value of reflux events preceding PSPWs was tangentially but not significantly lower [(mean ± SD) 2.61 ± 1.22 vs. 2.74 ± 1.26, p: 0.057].

CONCLUSIONS AND INFERENCES

Acid, mixed and proximal refluxes, and their duration are key factors in eliciting PSPWs. PSPW represents a response to reflux directly related to the potential harmfulness of reflux contents.

Characteristics of symptomatic reflux episodes in Japanese proton pump inhibitor-refractory non-erosive reflux disease patients

AIM: To clarify the pathogenesis of gastroesophageal reflux disease symptoms in non-erosive reflux disease (NERD) patients.

METHODS: Thirty-five NERD patients with persistent symptoms, despite taking rabeprazole 10 mg twice daily for at least 8 wk, were included in this study. All patients underwent 24 h combined impedance - pH on rabeprazole. The symptom index (SI) was considered to be positive if ≥ 50%, and proximal reflux episodes were determined when reflux reached 15 cm above the proximal margin of the lower esophageal sphincter.

RESULTS: In 14 (40%) SI-positive patients, with liquid weakly acid reflux, the occurrence rate of reflux symptoms was significantly more frequent in proximal reflux episodes (46.7%) than in distal ones (5.7%) (P < 0.001). With liquid acid reflux, there were no significant differences in the occurrence rate of reflux symptoms between proximal reflux episodes (38.5%) and distal ones (20.5%) (NS). With mixed liquid-gas weakly acid reflux, the occurrence rate of reflux symptoms in proximal reflux episodes was significantly more frequent (31.0%) than in distal reflux ones (3.3%) (P < 0.001). With mixed liquid-gas acid reflux, there were no significant differences in the occurrence rate of reflux symptoms between proximal reflux episodes (29.4%) and distal ones (14.3%) (NS).

CONCLUSION: The proximal extent of weakly acidic liquid and mixed liquid-gas reflux is a major factor associated with reflux perception in SI-positive patients on proton pump inhibitor therapy.

Pathophysiology of gastro-esophageal reflux disease: a role for mucosa integrity?

BACKGROUND

Gastro-esophageal reflux disease (GERD) is very prevalent and has a high burden on health security system costs. Nevertheless, pathophysiology is complex and not well-understood. Several mechanisms have been proposed: decreased salivation, impaired esophageal clearance, decreased lower esophageal sphincter pressure resting tone, presence of hiatal hernia, increased number of transient lower esophageal sphincter relaxations (TLESRs), increased acid, and pepsin secretion, pyloric incompetence provoking duodeno-gastro-esophageal reflux of bile acids and trypsin. Independent of the relevance of each mechanism, the ultimate phenomenon is that mucosal epithelium is exposed for a longer time to agents as acid and pepsin or is in contact to luminal agents not commonly present in gastric refluxate as trypsin or bile acids. This leads to a visible damage of the epithelium (erosive esophagitis -EE) or impairing mucosal integrity without any sign of macroscopic alteration as occurs in non-erosive reflux disease (NERD). Luminal factors are not the only responsible for such impairment; more recent data indicate that endogenous factors may also play a role.

PURPOSE

This review will update the most recent findings on the putative pathophysiological mechanisms and specially will focus on the role of esophageal mucosal integrity in GERD. Methodologies used for the evaluation of mucosal integrity, its relevance in EE and NERD, its involvement in symptoms perception and the effect of luminal and endogenous factors will be discussed.

Impedance baseline and reflux perception in responder and non-responder non-erosive reflux disease patients

BACKGROUND

It was recently shown that GERD patients have lower impedance baseline (IB) values than healthy controls and, that the esophageal acid exposure time (AET) correlates with IB levels.

GOALS

To explore the sensitivity of IB measurements in NERD patients, responders and non-responders to PPIs, when compared with pH-impedance (MII-pH) variables, and to evaluate whether this variable could represent a marker of GERD symptoms. Reproducibility and inter-observer agreement of IB measurement were also assessed. Study. MII-pH tracings from 44 NERD responders and 22 non-responders were analysed. Ten healthy volunteers underwent the same protocol. IB values were measured at the distal and proximal esophagus. IB was also analysed in a subgroup of patients and in controls with two methods and by two blinded operators.

RESULTS

Mean IB values at the distal esophagus were significantly lower in NERD patients than in controls. IB values did not differ between responders and non-responders. Of the 8 responders with negative AET and symptom association probability (SAP), 3 (37.5%) showed IB values lower than controls. IB values in responders with positive and negative SAP were similar (1832 (1596-2068) Ω vs 1667 (1361-1973) Ω, p: n.s.). No differences were found between the IB values measured with the two methods and the inter-observer agreement was good.

CONCLUSIONS

IB is a promising and easy to calculate MII-pH variable and appears to increase the sensitivity of MII-pH monitoring. IB values cannot predict PPI response and are not associated with reflux perception in NERD patients.

Alginate controls heartburn in patients with erosive and nonerosive reflux disease

AIM: To evaluate the effect of a novel alginate-based compound, Faringel, in modifying reflux characteristics and controlling symptoms.

METHODS: In this prospective, open-label study, 40 patients reporting heartburn and regurgitation with proven reflux disease (i.e., positive impedance-pH test/evidence of erosive esophagitis at upper endoscopy) underwent 2 h impedance-pH testing after eating a refluxogenic meal. They were studied for 1 h under basal conditions and 1 h after taking 10 mL Faringel. In both sessions, measurements were obtained in right lateral and supine decubitus positions. Patients also completed a validated questionnaire consisting of a 2-item 5-point (0-4) Likert scale and a 10-cm visual analogue scale (VAS) in order to evaluate the efficacy of Faringel in symptom relief. Tolerability of the treatment was assessed using a 6-point Likert scale ranging from very good (1) to very poor (6).

RESULTS: Faringel decreased significantly (P < 0.001), in both the right lateral and supine decubitus positions, esophageal acid exposure time [median 10 (25th-75th percentil 6-16) vs 5.8 (4-10) and 16 (11-19) vs 7.5 (5-11), respectively] and acid refluxes [5 (3-8) vs 1 (1-1) and 6 (4-8) vs 2 (1-2), respectively], but increased significantly (P < 0.01) the number of nonacid reflux events compared with baseline [2 (1-3) vs 3 (2-5) and 3 (2-4) vs 6 (3-8), respectively]. Percentage of proximal migration decreased in both decubitus positions (60% vs 32% and 64% vs 35%, respectively; P < 0.001). Faringel was significantly effective in controlling heartburn, based on both the Likert scale [3.1 (range 1-4) vs 0.9 (0-2); P < 0.001] and VAS score [7.1 (3-9.8) vs 2 (0.1-4.8); P < 0.001], but it had less success against regurgitation, based on both the Likert scale [2.6 (1-4) vs 2.2 (1-4); P = not significant (NS)] and VAS score [5.6 (2-9.6) vs 3.9 (1-8.8); P = NS]. Overall, the tolerability of Faringel was very good 5 (2-6), with only two patients reporting modest adverse events (i.e., nausea and bloating).

CONCLUSION: Our findings demonstrate that Faringel is well-tolerated and effective in reducing heartburn by modifying esophageal acid exposure time, number of acid refluxes and their proximal migration.

Increased frequency and enhanced perception of reflux in non-erosive reflux disease patients non-responders to proton pump inhibitors

BACKGROUND

The unsatisfactory response to medical treatment in non-erosive patients is becoming a real challenge for gastroenterologists. Non-responder patients, evaluated under treatment, present symptoms which are related to non-acidic, mixed and proximal reflux episodes.

METHODS

To elucidate the reflux pattern and mechanisms related to persistence of symptoms despite treatment, oesophageal pH-impedance was performed in 55 non-erosive responder and 24 non-responder patients, studied off therapy. Ten responder and 10 non-responder patients underwent a repeated study during proton pump inhibitor treatment.

RESULTS

Non-responders were characterised by a higher overall number and larger proportion of symptomatic reflux episodes. Non-responders were also characterised by an enhanced sensitivity to acidic, mixed and proximal refluxes. Weakly acidic reflux accounted for 29% of symptomatic refluxes in non-responders and 34% in responders. Proportions of acidic and weakly acidic reflux episodes were comparable both in responders and non-responders when analysed off and on treatment.

CONCLUSIONS

An increased overall number of reflux episodes and enhanced sensitivity to reflux are strongly associated with treatment failure. Treatment strategies aimed at decreasing transient lower oesophageal sphincter relaxations, pain modulators or anti-reflux surgery should be considered in non-responders in whom a significant relationship between symptoms and reflux has been confirmed.

Pathogenesis of proton-pump inhibitor-refractory non-erosive reflux disease according to multichannel intraluminal impedance-pH monitoring

BACKGROUND AND AIM

Proton-pump inhibitor (PPI) therapy is the first-line treatment for gastroesophageal reflux disease; however, there are some reports of PPI failure in cases of non-erosive reflux disease (NERD). Among the pathogenic factors associated with PPI-refractory NERD, reflux other than acid reflux can not be detected by conventional pH monitoring. The purpose of this study was to clarify the usefulness of multichannel intraluminal impedance-pH (MII-pH) monitoring for PPI-refractory NERD patients and examine the pathogenesis.

METHODS

We used MII-pH monitoring to examine 29 PPI-refractory NERD patients on PPI treatment. Reflux parameters, symptom index (SI: positive if ≥ 50%), and proximal migration were analyzed. The acidity of the reflux was divided into acid (nadir pH ≤ 4) and non-acid (nadir pH > 4). Subjects were classified into reflux-related disease (abnormal reflux parameters or positive SI) and non-reflux-related disease (normal reflux parameters and negative SI).

RESULTS

Of the 29 subjects, 21 were diagnosed with reflux-related disease, including 6 with acid reflux type and 15 with non-acid reflux type, and 8 were diagnosed with non-reflux-related disease. Of the total 1816 liquid reflux episodes, 834 showed proximal migration, which was more common in symptomatic reflux than in asymptomatic reflux.

CONCLUSIONS

MII-pH monitoring could distinguish reflux-related disease (especially non-acid type) from PPI-refractory NERD. Proximal migration was associated with symptomatic reflux in PPI-refractory NERD patients.

Effect of age on proximal esophageal response to swallowing

CONTEXT

It has been demonstrated that the ageing process affects esophageal motility.

OBJECTIVES

To evaluate the effect of the age on the proximal esophageal response to wet swallows.

METHOD

We measured the proximal esophageal response to swallows of a 5 mL bolus of water in 69 healthy volunteers, 20 of them aged 18-30 years (group I), 27 aged 31-50 years (group II), and 22 aged 51-74 years (group III). We used the manometric method with continuous perfusion. The proximal esophageal contractions were recorded 5 cm from a pharyngeal recording site located 1 cm above the upper esophageal sphincter. The time between the onset of the pharyngeal and of the proximal esophageal recording (pharyngeal-esophageal time) and the amplitude, duration and area under the curve of the proximal esophageal contraction were measured.

RESULTS

The pharyngeal-esophageal time was shorter in group I subjects than in group II and III subjects (P<0.05). The duration of proximal esophageal contractions was longer in group I than in groups II and III (P<0.001). There was no differences between groups in the amplitude or area under the curve of contractions. There were no differences between groups II and III for any of the measurements.

CONCLUSION

We conclude that the age may affects the response of the proximal esophagus to wet swallows.

Increasing body weight enhances prevalence and proximal extent of reflux in GERD patients 'on' and 'off' PPI therapy

BACKGROUND

Increased body weight is associated with higher intragastric pressure. Proximal extent of reflux is a determinant of symptoms in patients with gastro-esophageal reflux disease (GERD). We aimed to investigate the association between body mass index (BMI) and abdominal circumference on the incidence and proximal extent of reflux.

METHODS

A total of 95 patients [37 men, age 51(16-82) years] with typical and/or atypical GERD symptoms underwent 24 h impedance-pH monitoring. Forty-nine patients were studied 'off' and 46 'on' proton pump inhibitors (PPI) treatment. Reflux was classified as acid (pH < 4) or weakly acidic (pH 4-7). Proximal extent was defined as the number of reflux events reaching ≥15 cm above the lower esophageal sphincter. Body mass index and abdominal circumference (cm) were assessed.

KEY RESULTS

In patients 'off' PPI, there was a correlation between BMI and esophageal acid exposure (ρ = 0.53, P < 0.001), volume exposure (ρ = 0.48, P < 0.001), total number of reflux events (ρ = 0.47, P < 0.001) and number of acid reflux events (ρ = 0.49, P < 0.001). In patients 'on' PPI there was a correlation between BMI and esophageal acid exposure (ρ = 0.32, P = 0.03), volume exposure (ρ = 0.46, P < 0.01) and total number of reflux events (ρ = 0.33, P = 0.03). Similar correlations were found between abdominal circumference and reflux. A correlation between BMI and proximal extent of reflux was present in patients 'off' PPI (ρ = 0.32, P = 0.03). In patients 'on' PPI, we found a correlation between abdominal circumference and proximal extent (ρ = 0.31, P = 0.03).

CONCLUSIONS & INFERENCES

Body mass index and abdominal circumference may contribute to GER and its proximal extent, in patients 'on and 'off' PPI. Further studies investigating the role of weight reduction in the control of GERD symptoms are warranted.

Measurement of acid exposure of proximal esophagus: a better tool for diagnosing non-erosive reflux disease

BACKGROUND

The sensitivity of 24-h pH monitoring is poor in non-erosive reflux disease (NERD). In NERD patients, the proximal extent of acid reflux is one of the main determinants of reflux perception. The present study was aimed to compare the diagnostic accuracy of acid exposure time (AET), at 5 cm above the lower esophageal sphincter, with those at 10 cm and at 3 cm below the upper esophageal sphincter as well as the reproducibility of these parameters.

METHODS

A total of 93 consecutive NERD patients, with typical symptoms responsive to proton pump inhibitor treatment, and 40 controls underwent esophageal manometry and multi-channel 24-h pH-test; 13 patients underwent the same study on two occasions. Symptom association probability (SAP) values were evaluated at each esophageal level.

KEY RESULTS

The ROC curve indicates that the area under the curve was 0.79 at distal (SE=0.039), 0.87 (SE=0.032) at proximal (P=0.029 vs distal), and 0.85 (SE=0.033) at very proximal esophagus (P =0.148). AET showed a reproducibility of 61% (Kappa 0.22) at distal esophagus, 77% (Kappa 0.45) at proximal and 53% (Kappa 0.05) at very proximal esophagus. The percentage of patients with a positive SAP was not significantly different when assessed at the distal compared with the proximal esophagus.

CONCLUSIONS & INFERENCES

In NERD patients, the diagnostic yield of the pH test is significantly improved by the assessment of AET at the proximal esophagus. As this variable seems to be less affected by the day to day variability, it could be considered a reliable and useful diagnostic tool in NERD patients.