Prevalence of ineffective esophageal motility and its relevance to symptoms and esophageal acid exposure in korean patients referred for foregut symptoms

Effect of hiatus hernia on reflux patterns and mucosal integrity in patients with non-erosive reflux disease

BACKGROUND

Hiatus hernia (HH) contributes to development of gastroesophageal reflux disease, Barrett's esophagus and esophageal adenocarcinoma. This study was aimed to investigate the influence of HH on reflux patterns and distal esophageal mucosal integrity in non-erosive reflux disease (NERD).

METHODS

We retrospectively analyzed PPI-refractory NERD patients referred to three tertiary referral centers who underwent high-resolution manometry and off-PPI 24-h impedance-pH monitoring (with or without bile spectrophotometry). Patients with HH ≥2 cm (HH group, n = 42) or no HH (non-HH group, n = 40) with similar esophageal acid exposure time (AET 6%-12%) were included.

KEY RESULTS

Age, gender, BMI, esophageal motility, AET, and esophageal clearance were similar between the two groups. The HH group had higher numbers of total reflux episodes (p = 0.015) with similar proportion of acid/non-acid reflux compared with the non-HH group. Mean nocturnal baseline impedance (MNBI) in the distal esophagus was significantly lower in the HH group than the non-HH group at both 5 cm (p = 0.002) and 3 cm (p = 0.015) above the lower esophageal sphincter. Multivariable regression analysis showed that HH, less non-acid reflux and lower post-reflux swallow-induced peristaltic wave index (PSPWI) were independently associated with lower MNBI. Among 31 patients tested with bile spectrophotometry, the HH group had significantly longer bile exposure time than the non-HH group (p = 0.011), and bile reflux inversely and significantly correlated with MNBI (rho = -0.75, p < 0.001).

CONCLUSIONS AND INFERENCES

Hiatus hernia, less non-acid reflux and lower PSPWI were associated with lower MNBI. HH impairs distal esophageal mucosal integrity, the mechanism of which we speculate to be through excessive bile 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.

Gastroesophageal reflux symptoms in typical and atypical GERD: roles of gastroesophageal acid refluxes and esophageal motility

BACKGROUND/AIM

To determine the roles of gastroesophageal acid reflux (GER) and esophageal dysmotility on typical and atypical GERD symptoms.

METHODS

Two hundred thirty-six patients (159 females, age 47 ± 14 years) with typical and atypical GERD symptom(s) for > 3 months underwent standard water perfused esophageal manometry (EM) and 24 h esophageal pH studies during off therapy.

RESULTS

Eighty seven and 93 patients had positive lower esophageal pH tests and abnormal EM, respectively. Patients with positive lower esophageal pH test were significantly older (50 ± 13 vs 45 ± 13 years, P < 0.005) and had higher prevalence of acid regurgitation symptoms than patients with negative test (56/87 vs 72/149, P < 0.05). Patients with positive upper esophageal pH test (n = 67) also had significantly higher prevalence of acid regurgitation symptoms (43/67 vs 74/152, P < 0.05). Prevalence of other upper gastrointestinal and respiratory symptoms were similar between patients with positive and negative upper and lower pH test. Patients with abnormal EM were significantly older (49 ± 14 vs 45 ± 13 years, P < 0.05) and had higher prevalence of chronic cough than patients with normal EM(30/93 vs 26/143, P < 0.05). In patients with positive pH tests, the prevalence of dysphagia, chronic cough, and hoarseness of voice were significantly higher in patients with abnormal than those with normal EM (18/31 vs 18/56, P < 0.05; 12/31 vs 6/56, P < 0.005 and 19/31 vs 18/56, P < 0.01, respectively). Whereas in patients with negative lower pH tests, only the prevalence of heartburn was significantly lower in patients with normal than those with abnormal EM (26/87 vs 30/62, P < 0.05).

CONCLUSIONS

Acid regurgitation but not heartburn was associated with GER. Esophageal dysmotility had no significant effect on acid regurgitation symptom but associated with chronic cough, hoarseness of voice, and dysphagia only in patients with abnormal esophageal acid exposure.

Heterogeneity in oesophageal dysfunction among patients with different reflux symptoms

BACKGROUND AND AIM

Ineffective oesophageal motility (IOM) often occurs in patients with gastro-oesophageal reflux disease. We aimed to examine the hypothesis of whether the presence of IOM differs between patients with gastro-oesophageal reflux disease with different symptom profiles.

METHODS

Eligible patients were subclassified according to their predominant symptom of heartburn (HB) or acid regurgitation (AR). All patients underwent combined multichannel intraluminal impedance and oesophageal manometry. IOM was further graded according to the presence of oesophageal transit abnormalities.

RESULTS

Fourteen healthy individuals, 16 HB patients and 24 AR patients participated in this study. The percentage of swallows with complete bolus transit was lower in AR than in HB patients during liquid and viscous swallowing (P<0.05). Abnormal bolus transit occurred more frequently in AR patients than in HB patients with liquid swallows (P<0.001) and viscous swallows (P<0.05). IOM occurred more frequently in AR patients than in HB patients (42.7 vs. 12.5%, P=0.049). In patients with IOM, severe functional abnormality was more frequently found in AR patients than in HB patients (P<0.05).

CONCLUSION

This study suggests a potential link between oesophageal body dysfunction and individual reflux symptom. Patients with a predominant symptom of AR are characterized by greater IOM and defective bolus clearance.

Role of the lower esophageal sphincter on acid exposure revisited with high-resolution manometry

BACKGROUND

The objective of this study was to investigate the role of lower esophageal sphincter (LES) length and pressure on acid exposure with high-resolution manometry (HRM).

STUDY DESIGN

After Institutional Review Board approval, a retrospective review of a prospectively maintained database identified patients who had undergone HRM and 24-hour pH studies. Abdominal LES length (AL) ≤1 cm and overall LES length ≤2 cm were considered inadequate. A new parameter called lower esophageal sphincter pressure integral (LESPI) was analyzed in this study. Distal esophageal acid exposure was analyzed in relation to LES parameters.

RESULTS

One hundred eight patients (inadequate AL, n = 54; inadequate overall LES length, n = 54) satisfied study criteria. Patients with inadequate AL had considerably lower LESPI and LES pressure. They also had more severe acid exposure and higher DeMeester score. However, inadequate overall LES length was not associated with abnormal acid exposure. Patients with a positive pH study had considerably lower LESPI than patients with a negative pH study. Inadequate AL and low LESPI (<400 mmHg/s/cm) had a synergistic effect on acid reflux. Multivariate logistic regression analysis identified inadequate AL, low LESPI, and male sex as predictors of a positive pH study.

CONCLUSIONS

Using HRM, inadequate AL (≤1cm) and low LESPI (<400 mmHg/s/cm) are associated with gastroesophageal reflux disease and appear to have a synergistic effect on the severity of distal esophageal acid exposure. LESPI, which is a function of both sphincter length and pressure, appears to be the most sensitive HRM parameter for distal esophageal acid exposure.

Developments in pathogenesis and diagnosis of gastroesophageal reflux disease

PURPOSE OF REVIEW

Although gastroesophageal reflux is a common disorder, diagnosis is still imprecise. Moreover, its pathogenesis is incompletely understood. This review summarizes recent progress in diagnosis and our understanding of the pathogenesis of gastroesophageal reflux disease.

RECENT FINDINGS

Recent studies have focused on the pattern of reflux in the distal esophagus, just above the esophago-gastric junction, challenging its importance on the genesis of reflux symptoms. New techniques, such as impedance, could improve the diagnostic yield, especially in patients with nonacid reflux. Esophageal sensitivity and motility, transient lower esophageal sphincter relaxations, and hiatus hernia are important pathogenic mechanisms of reflux disease. Studies showed that obesity plays a role in the pathogenesis of reflux symptoms; a disruption of the esophago-gastric junction (leading to hiatus hernia) could allow reflux to occur. The association between reflux (particularly nonacid) and extraesophageal manifestations of gastroesophageal reflux disease has been further evaluated.

SUMMARY

Improvement of diagnostic techniques and better understanding of the pathogenesis of reflux may lead to new or better therapeutic modalities. Our understanding of some of the risk factors for reflux has been increased. Extra-esophageal manifestations and their association with gastroesophageal reflux are still a very controversial and promising area of research.