Relevance of ineffective esophageal motility and hyperactive acid sensitization in patients with gastroesophageal reflux

Esophageal mucosal sensory nerves and potential mechanoreceptors in patients with ineffective esophageal motility

BACKGROUND

Ineffective esophageal motility (IEM) is the most common motility disorder. However, little is known about its pathophysiology. Vagal afferent nerves convey esophageal intraluminal bolus information to solitary nucleus, which is likely to be involved with esophageal primary and secondary peristalsis (SP). We hypothesized that altered mucosal sensory afferents underlie the pathogenesis of IEM.

METHODS

We prospectively collected esophageal biopsies from 38 patients with proton pump inhibitor-refractory reflux symptoms from January to December 2019. All patients underwent high-resolution manometry for the evaluation of primary and secondary peristalsis, and off-PPI 24-h impedance-pH studies. Biopsies were analyzed using immunohistochemistry for identification of calcitonin gene-related peptide-immunoreactive (CGRP-IR) nerves and qPCR for mRNA expression of potential mechanoreceptors.

KEY RESULTS

Overall 32 patients were finally analyzed which consisted of 11 patients with normal motility and 21 patients with IEM. The position of mucosal CGRP-IR nerves from the esophageal lumen did not differ between the two groups (the proximal esophagus (p = 0.52), the mid-esophagus (p = 0.92), the distal esophagus (p = 0.29)) with the similar reflux profile. No difference was seen in the position of CGRP-IR nerves between patients with successful triggering of SP and those unable to trigger SP. There was also no difference in mRNA expression of each potential mechanoreceptors (TRPA1, TRPV1, TRPV4, ASIC1, ASIC3) between the two groups.

CONCLUSIONS AND INFERENCES

Our study showed that mucosal sensory afferents nerve position and mRNA expression of potential mechanoreceptors did not correlate to weak esophageal contraction.

Psychological intervention for auxiliary treatment of non-erosive reflux disease

Non-erosive reflux disease (NERD) is an independent subtype of gastroesophageal reflux disease, and it is often concomitant with anxiety and/or depression, which seriously influence the patient's quality of life. This article summarizes the research progress of NERD with regard to the pathogenesis of NERD and NERD with anxiety and/or depression, the effect of common treatments on NERD, and psychological intervention for auxiliary treatment of NERD (including establishing a good relationship between doctors and patients, psychological hints, health education, social support and so on). Some deficiencies in the understanding and treatment of NERD are pointed out. In addition, the following suggestions are put forward: more attention should be paid to the psychological factors of patients and psychological intervention should be adopted in the clinical practice and study of NERD; further research should be made on the mechanism of psychological intervention so as to form a unified understanding; epidemiological research and evidence-based medicine research should be carried out to explore the psychological intervention norms on NERD with anxiety and/or depression, in order to improve the curative effect of NERD and the quality of life of patients.

The role of gastroesophageal reflux in relation to symptom onset in patients with proton pump inhibitor-refractory nonerosive reflux disease accompanied by an underlying esophageal motor disorder

BACKGROUND

The symptom improvement rate is low with proton pump inhibitors (PPIs) in nonerosive reflux disease (NERD). The underlying pathogenic mechanism is complex. Esophageal motility disorders (EMDs) are thought to be a factor, but their prevalence, type, symptoms and the role played by gastroesophageal reflux (GER) in symptom onset have not been fully investigated.

AIM

To investigate the role of GER in symptom onset in PPI-refractory NERD patients with EMDs.

METHODS

This study comprised 76 patients with PPI-refractory NERD. Manometry was performed during PPI treatment and patients were divided into an EMD group and normal motility (non-EMD) group. Then, multichannel intraluminal impedance-pH monitoring was performed and medical interviews were conducted.

RESULTS

Nineteen patients (25%) had an EMD. Data were compared between 17 patients, excluding 2 with achalasia and 57 non-EMD patients. No significant differences were observed between groups in 24-hour intraesophageal pH <4 holding time (HT), mean number of GER episodes or mean number of proximal reflux episodes. The reflux-related symptom index (≥50%) showed a relationship between reflux and symptoms in 70.5% of EMD patients and 75% of non-EMD patients. In the EMD group, the score for FSSG (Frequency Scale for the Symptoms of GERD) question (Q)10 was significantly correlated with the number of GER episodes (r = 0.58, p = 0.02) and the number of proximal reflux episodes (r = 0.63, p = 0.02). In addition, the score for Q9 tended to be correlated with the number of GER episodes (r = 0.44, p = 0.06).

CONCLUSION

Our results suggest that some PPI-refractory NERD patients have EMDs, and that GER plays a role in symptom onset.

Functional heartburn: clinical characteristics and outcome

OBJECTIVES

Patients with heartburn and normal upper gastrointestinal endoscopy, normal oesophageal acid exposure, no symptom-reflux association and who fail to respond to a proton-pump inhibitor are classified as having functional heartburn (FH). This study aimed (i) to characterize the symptoms and functional abnormalities of patients with FH and (ii) to describe their clinical outcome.

MATERIALS AND METHODS

Among all patients referred for 24 h multichannel intraluminal impedance-pH (MII-pH), patients with FH were identified. The clinical characteristics and high-resolution oesophageal pressure topography recordings of FH patients were analyzed at the time of the 24-h MII-pH test. A symptom-related and health-related quality-of-life questionnaire was then sent to FH patients to assess the long-term outcome.

RESULTS

Forty patients fulfilled the criteria for FH, representing 8.5% of the referred population. Twenty-two months after initial testing, 66% of patients still suffered from heartburn. The rate of mixed reflux (liquid/gas) was higher in patients with persisting heartburn at the final evaluation (63 vs. 50%, P=0.04). Sixty-six per cent of patients had one or more manometric abnormalities. Acid clearance time in MII-pH was significantly higher in patients with weak peristalsis than patients with normal peristalsis (60 ± 45 vs. 31 ± 19 s, P=0.03). A high rate of mixed reflux and/or a manometric abnormality were associated with a higher risk of persistent heartburn.

CONCLUSION

FH is a chronic disorder with persisting symptoms in two-thirds of patients. An increased rate of mixed reflux and/or the presence of manometric abnormalities are associated with a higher risk of persisting symptoms and may help to identify the population with unmet therapeutic needs.

Mechanisms of increased gastroesophageal reflux in patients with cystic fibrosis

OBJECTIVES

Up to 80% of patients with cystic fibrosis (CF) may have increased gastroesophageal reflux (GER). It has been suggested that increased GER is due to low basal lower esophageal sphincter (LES) pressure and a high number of transient LES relaxations (TLESRs). The aim of our study was to reassess the mechanisms of GER in adult CF patients using state of the art upper-gastrointestinal physiology techniques: high-resolution manometry impedance (HRM-MII).

METHODS

We studied 12 CF patients (age 32 range (19-58), 5 males/7 females) and 11 age-matched healthy volunteers (age 27 range (20-36), 4 males /7 females). HRM-MII was performed in a semi-recumbent position for 30 min during fasting and for 2 h after a standard meal (1,000 kcal). We measured total reflux and proximal extent of reflux with impedance; basal LES pressure, TLESRs, and gastroesophageal pressure gradient (GEPG) with HRM.

RESULTS

Basal LES pressure was lower in CF patients compared with healthy controls, both in the pre- and postprandial period (preprandial 13 (7-22) vs. 24 (13-26) mm Hg, P = 0.04; postprandial 10 (8-14) vs. 18 (10-31) mm Hg, P = 0.01) and TLESRs were the main mechanism for reflux both in CF and in controls. We could not find a difference in the number of TLESRs in CF patients compared with healthy (14 (10-20) vs. 13 (10-24), P = not significant). However, reflux during TLESRs was more frequent in CF compared with healthy volunteers (80 (70-95) vs. 42 (20-78) %, P = 0.0058). GEPG during TLESRs was significantly higher in CF than in controls during inspiration (13.5 (9.5-15.8) vs. 7 (4-9.9) mm Hg, P = 0.004). This difference was due to a lower inspiratory intra-thoracic pressure in CF patients (-8.2 (-10.2-(-4.6) vs. -0.08 (-5.7-2.7) mm Hg, P = 0.002). Compared with controls, CF patients had significantly higher number of reflux episodes (13 (6-20) vs. 7 (3-9), P = 0.014) and CF patients also showed a higher proportion of reflux episodes with a high proximal extent compared with healthy volunteers (49 (22-50) vs. 0 (0-17) %, P = 0.0028).

CONCLUSIONS

CF patients have increased GER with a high proximal extent. Although we could not find a higher number of TLESRs in CF, there is a higher proportion of TLESRs associated with reflux. Unlike non-CF GER disease patients (with increased intra-abdominal pressure), reflux during TLESRs in CF is probably due to an increased GEPG mainly generated by a greater inspiratory negative intra-thoracic pressure.

Treatment of non-erosive reflux disease with a proton pump inhibitor in Chinese patients: a randomized controlled trial

BACKGROUND

Evidence suggests that rates of gastroesophageal reflux disease are increasing in the Asia-Pacific region, where patients tend to have predominantly non-erosive reflux disease as opposed to erosive (reflux) esophagitis. At present, data for the responsiveness of non-erosive reflux disease to proton pump inhibition are scant. We aimed to study esomeprazole for the treatment of non-erosive reflux disease in Chinese patients.

METHODS

Patients with a clinical diagnosis of gastroesophageal reflux, and a locally validated reflux index, the Chinese GerdQ, of equal to or greater than 12 were recruited and randomized to receive esomeprazole 20 mg daily or placebo for 8 weeks. Reflux index scores, quality of life (SF-36), and the hospital anxiety and depression (HAD) scale and symptom relief were evaluated before, during, and after treatment.

RESULTS

A total of 175 patients were randomized. Patients in the esomeprazole group (n = 85) demonstrated statistically significant reductions in their GerdQ index, from 19.45 to 15.37 and to 14.32 (p = 0.013, p = 0.005) at weeks 4 and 8, respectively. Compared to placebo at week 8, 57.1% of patients on esomeprazole found that their symptoms had resolved or were acceptable compared with 37.2% in the placebo group (p = 0.001). There were no statistically significant differences in overall quality-of-life measures or the HAD scale related to treatment.

CONCLUSIONS

This study suggests that esomeprazole is efficacious in treating Chinese patients with non-erosive reflux disease.

Differences in cerebral response to esophageal acid stimuli and psychological anticipation in GERD subtypes--an fMRI study

Background

To evaluate whether there are differences in the cerebral response to intraesophageal acid and psychological anticipation stimuli among subtypes of gastroesophageal reflux disease (GERD).

Methods

Thirty nine patients with GERD and 11 healthy controls were enrolled in this study after gastroscopy and 24 hr pH monitoring. GERD subjects were divided into four subgroups: RE (reflux esophagitis), NERD+ (non-erosive reflux disease with excessive acid reflux), NERD-SI+ (normal acid exposure and positive symptom index) and NERD-SI+ (normal acid exposure and negative symptom index, but responded to proton pump inhibitor trial). Cerebral responses to intraesophageal acid and psychological anticipation were evaluated with fMRI.

Results

During intraesophageal acid stimulation, the prefrontal cortex (PFC) region was significantly activated in all subgroups of GERD; the insular cortex (IC) region was also activated in RE, NERD+ and NERD-SI- groups; the anterior cingulated cortex (ACC) region was activated only in RE and NERD-SI- groups. The RE subgroup had the shortest peak time in the PFC region after acid was infused, and presented the greatest change in fMRI signals in the PFC and ACC region (P = 0.008 and P = 0.001, respectively). During psychological anticipation, the PFC was significantly activated in both the control and GERD groups. Activation of the IC region was found in the RE, NERD-SI+ and NERD-SI- subgroups. The ACC was activated only in the NERD-SI+ and NERD-SI- subgroups. In the PFC region, the NERD-SI- subgroup had the shortest onset time (P = 0.008) and peak time (P < 0.001). Compared with actual acid infusion, ACC in RE and IC in NERD+ were deactivated while additional areas including the IC and ACC were activated in the NERD-SI+ group; and in NERD-SI- group, onset-time and peak time in the PFC and IC areas were obviously shorter in induced anticipation than in actual acid infusion.

Conclusions

The four subgroups of GERD patients and controls showed distinctly different activation patterns and we therefore conclude GERD patients have different patterns of visceral perception and psychological anticipation. Psychological factors play a more important role in NERD-SI+ and NERD-SI- groups than in RE and NERD+ groups.

Esophageal sensation and esophageal hypersensitivity - overview from bench to bedside

Noxious stimuli in the esophagus activate nociceptive receptors on esophageal mucosa, such as transient receptor potential, acid-sensing ion channel and the P2X family, a family of ligand-gated ion channels responsive to ATP, and this generates signals that are transmitted to the central nervous system via either spinal nerves or vagal nerves, resulting in esophageal sensation. Among the noxious stimuli, gastric acid and other gastric contents are clinically most important, causing typical reflux symptoms such as heartburn and regurgitation. A conventional acid penetration theory has been used to explain the mechanism of heartburn, but much recent evidence does not support this theory. Therefore, it may be necessary to approach the causes of heartburn symptoms from a new conceptual framework. Hypersensitivity of the esophagus, like that of other visceral organs, includes peripheral, central and probably psychosocial factor-mediated hypersensitivity, and is known to play crucial roles in the pathoegenesis of nonerosive reflux disease, functional heartburn and non-cardiac chest pain. There also are esophagitis patients who do not perceive typical symptoms. This condition is known as silent gastroesophageal reflux disease. Although the pathogenesis of silent gastroesophageal reflux disease is still not known, hyposensitivity to reflux of acid may possibly explain the condition.

Gastroesophageal reflux disease: an Asian perspective

The prevalence of gastroesophageal reflux disease (GERD) ranges from 2.5% to 7.1% in most population-based studies in Asia. There is evidence that GERD and its complications are rising, coinciding with a decline in Helicobacter pylori (H. pylori) infection. Asian GERD patients share similar risk factors and pathophysiological mechanisms with their Western counterparts. Possible causes for the lower prevalence of GERD include less obesity and hiatus hernia, a lesser degree of esophageal dysmotility, a high prevalence of virulent strains of H. pylori, and low awareness. Owing to the lack of precise translation for 'heartburn' in most Asian languages, reflux symptoms are often overlooked or misinterpreted as dyspepsia or chest pain. Furthermore, a symptom-based diagnosis with a therapeutic trial of the proton pump inhibitor (PPI) may be hampered by the high prevalence of H. pylori-related disease. The risk stratification for prompt endoscopy, use of a locally-validated, diagnostic symptom questionnaire, and response to H. pylori'test and treat' help improve the accuracy of the PPI test for diagnoses. PPI remain the gold standard treatment, and 'on-demand' PPI have been shown to be a cost-effective, long-term treatment. The clinical course of GERD is benign in most patients in Asia. The risk of progression from non-erosive reflux disease to erosive esophagitis is low, and treatment response to a conventional dose of PPI is generally higher. Although H. pylori eradication may lead to more resilient GERD in a subset of patients, the benefits of H. pylori eradication outweigh the risks, especially in Asian populations with a high incidence of gastric cancer.

Advances in esophageal motor disorders

PURPOSE OF REVIEW

Esophageal motor disorders, often leading to dysphagia and chest pain, continue to pose diagnostic and therapeutic problems. In the past 12 months important new information regarding esophageal motor disorders was published. This information will be reviewed in this paper.

RECENT FINDINGS

A number of studies have addressed the issue of heterogeneity in achalasia, the best defined esophageal motility disorder. The spastic esophageal motility disorders nutcracker esophagus and diffuse esophageal spasm may coexist with gastroesophageal reflux disease, which has consequences for the management of patients with these disorders. The entity labelled ineffective esophageal motility is associated with reflux esophagitis, but also with morbid obesity. For the detection of disordered transit caused by ineffective esophageal motility, application of intraluminal impedance monitoring in conjunction with manometry leads to improved diagnosis. New data on the effect of Nissen fundoplication on esophageal motility were published during the last year.

SUMMARY

Recent knowledge on the heterogeneity of achalasia and the association of spastic esophageal motor disorders and ineffective motility with reflux disease will help the clinician in the management of patients with these disorders.

Physiology of the oesophageal transition zone in the presence of chronic bolus retention: studies using concurrent high resolution manometry and digital fluoroscopy

Distinct contraction waves (CWs) exist above and below the transition zone (TZ) between the striated and smooth muscle oesophagus. We hypothesize that bolus transport is impaired in patients with abnormal spatio-temporal coordination and/or contractile pressure in the TZ. Concurrent high resolution manometry and digital fluoroscopy were performed in healthy subjects and patients with reflux oesophagitis; a condition associated with ineffective oesophageal contractility and clearance. A detailed analysis of space-time variations in bolus movement, intra-bolus and intra-luminal pressure was performed on 17 normal studies and nine studies in oesophagitis patients with impaired bolus transit using an interactive computer based system. Compared with normal controls, oesophagitis patients had greater spatial separation between the upper and lower CW tails [median 5.2 cm (range 4.4-5.6) vs 3.1 cm (2.2-3.7)], the average relative pressure within the TZ region (TZ strength) was lower [30.8 mmHg (28.3-36.5) vs 45.8 mmHg (36.1-55.7), P < 0.001], and the risk of bolus retention was higher (90%vs 12%; P < 0.01). The presence of bolus retention was associated with a wider spatial separation of the upper and lower CWs (>3 cm, the upper limit of normal; P < 0.002), independent of the presence of oesophagitis. We conclude that bolus retention in the TZ is associated with excessively wide spatial separation between the upper and lower CWs and lower TZ muscle squeeze. These findings provide a physio-mechanical basis for the occurrence of bolus retention at the level of the aortic arch, and may underlie impaired clearance with reflux oesophagitis.