Evolving issues in the management of reflux disease?

Risk Factors for Gastroesophageal Reflux Disease in Saudi Arabia

Background

Gastroesophageal reflux disease (GERD) is one of the most prevalent gastrointestinal tract diseases worldwide. GERD has an effect on the patients' quality of life as well as the health care system that can be prevented by identifying its risk factors among the population. Hence, we applied this study to assess the GERD's risk factors in Saudi Arabia.

Methods

A cross-sectional study was designed to assess the GERD's risk factors among the community of Saudi Arabia. The sample was collected randomly during the period from November to December 2016. Through a self-administered validated GERD questionnaire (GerdQ), GERD was diagnosed. Then, the GERD's risk factors were assessed among all participants. The data were analyzed using Statistical Package for Social Sciences version 21.0; the Student's t-test was used to assess the association of GERD and risk factors.

Results

A total of 2,043 subjects participated in the study. The characteristics and behaviors of participants statistically significant with GERD were positive family history (39.3%), obese (body mass index > 30 kg/m²) (39.4%), not performing weekly regular physical activities ≥ 30 min (31.1%) and smoking (39.3%). GERD was commonly noticed in participants on analgesics (38.4%), not taking fibers (37.4%), drinking tea (33.4%), eating greasy (31.2%) and fast food (32.7%), and these were statistically significant with GERD (P ≤ 0.05).

Conclusion

The characteristics and behaviors associated with GERD in Saudi population are family history of GERD, obesity, sedentary lifestyle and smoking. Other common risk factors correlated with GERD are analgesics intake, no fibers intake, drinking tea, greasy and fast food intake.

Endoscopic Options for Gastroesophageal Reflux: Where Are We Now and What Does the Future Hold?

Early in the twenty-first century, novel endoscopic techniques were introduced for the management of gastroesophageal reflux disease, providing minimally invasive ways to eliminate pharmacologic acid inhibition and avoid the need for anti-reflux surgery. These techniques do not significantly alter the anatomy of the gastroesophageal junction, minimizing short- and long-term adverse effects, such as dysphagia and bloating. After extensive clinical testing, many endoscopic therapies were abandoned due to either lack of durable efficacy or unfavorable safety profile. Today, only four such therapies remain clinically available, each with variable levels of clinical validation and market penetration. This review will provide an assessment of these endoscopic therapies, highlighting their respective strengths and weaknesses and their present and future applicability to patients with gastroesophageal reflux disease.

Contribution of immunomodulators to gastroesophageal reflux disease and its complications: stromal cells, interleukin 4, and adiponectin

Gastroesophageal reflux disease (GERD) has become the most commonly seen gastrointestinal disorder in outpatient clinics. In the United States, around 20% of the general population experience heartburn on a weekly basis. Although clinical complaints can be mild or moderate, patients with GERD may develop further complications, such as peptic strictures, Barrett's esophagus (BE), and even esophageal adenocarcinoma. Pathologically, GERD is developed as a result of chronic and enhanced exposure of the esophageal epithelium to noxious gastric refluxate. In this review article, we provide an overview of GERD and then focus on the roles of stromal cells, interleukin 4, and adiponectin in GERD and BE. The importance of inflammation and immunomodulators in GERD pathogenesis is highlighted. Targeting the immunomodulators or inflammation in general may improve the therapeutic outcome of GERD, in particular, in those refractory to proton pump inhibitors.

How can we deal with the GERD treatment gap?

Patients experiencing heartburn and acid regurgitation despite proton pump inhibition therapy who are averse to antireflux surgery fall into what is called the gastroesophageal reflux disease (GERD) treatment gap. This gap may be potentially addressed by several endoscopic and laparoscopic techniques, including gastric bypass surgery for those patients who are obese. These novel techniques do not significantly alter the anatomy of the esophagogastric junction, minimizing short- and long-term adverse effects. This review provides an overview of the assessment of patients with refractory GERD and highlights the strengths and weaknesses of these minimally invasive therapies.

Potassium-Competitive Acid Blockers (P-CABs): Are They Finally Ready for Prime Time in Acid-Related Disease?

The need for new acid suppressing agents with improved pharmacology and superior antisecretory effects to address unmet clinical needs in acid-related disorders has been evident for over a decade. Recent new antisecretory drugs (IR-omeprazole and MR-dexlansoprazole) only provide a small incremental advance in control of acid secretion over the delayed-release proton pump inhibitors. Vonoprazan (a new potassium-competitive acid blocker) displays more potent and extended 24 h acid suppression and preliminary Japanese trials translate this into meaningful clinical benefits in gastro-esophageal reflux disease and Helicobacter pylori eradication. We review the vonoprazan information to date and the indications, benefits, and concerns of more effective therapeutic control of acid secretion.

Nrf2 deficiency impairs the barrier function of mouse oesophageal epithelium

OBJECTIVE

As a major cellular defence mechanism, the Nrf2/Keap1 pathway regulates expression of genes involved in detoxification and stress response. Here we hypothesise that Nrf2 is involved in oesophageal barrier function and plays a protective role against gastro-oesophageal reflux disease (GERD).

DESIGN

Human oesophageal biopsy samples, mouse surgical models and Nrf2(-/-) mice were used to assess the role of the Nrf2/Keap1 pathway in oesophageal barrier function. Trans-epithelial electrical resistance (TEER) was measured with mini-Ussing chambers. HE staining and transmission electron microscopy were used to examine tissue morphology, while gene microarray, immunohistochemistry, western blotting and chromatin immunoprecipitation (ChIP) analysis were used to assess gene expression.

RESULTS

Nrf2 was expressed in normal oesophageal epithelium and activated in GERD of both humans and mice. Nrf2 deficiency and gastro-oesophageal reflux in mice, alone or in combination, reduced TEER and increased intercellular space in oesophageal epithelium. Nrf2 target genes and gene sets associated with oxidoreductase activity, mitochondrial biogenesis and energy production were downregulated in the oesophageal epithelium of Nrf2(-/-) mice. Consistent with the antioxidative function of Nrf2, a DNA oxidative damage marker (8OHdG) dramatically increased in oesophageal epithelial cells of Nrf2(-/-) mice compared with those of wild-type mice. Interestingly, ATP biogenesis, Cox IV (a mitochondrial protein) and Claudin 4 (Cldn4) expression were downregulated in the oesophageal epithelium of Nrf2(-/-) mice, suggesting that energy-dependent tight junction integrity was subject to Nrf2 regulation. ChIP analysis confirmed the binding of Nrf2 to Cldn4 promoter.

CONCLUSIONS

Nrf2 deficiency impairs oesophageal barrier function through disrupting energy-dependent tight junction.

Poor effectiveness of proton pump inhibitors in non-erosive reflux disease: the truth in the end!

Despite acid secretion being normal in the majority of patients with gastro-esophageal reflux disease (GERD) or Barrett's esophagus, acid inhibition represents the mainstay of treatment for both these conditions, with the aim of reducing the aggressive nature of the refluxate toward the esophageal mucosa. Proton pump inhibitors (PPIs) represent, therefore, the first choice medical treatment for GERD, in that they are able to provide an 80-85% healing rate for esophageal lesions, a 56-76% symptom relief and also reduce the incidence of complications, such as strictures as well as dysplasia and adenocarcinoma in Barrett's esophagus. According to a widely quoted systematic review, compared to patients with erosive esophagitis, patients with non-erosive reflux disease (i.e., NERD) display a reduced symptom relief with PPIs, with about 20% reduction of therapeutic gain. In this issue of NeuroGastroenterology & Motility, Weijenborg et al. address for the first time the PPI efficacy in subpopulations of patients with NERD. The study shows clearly that, when the diagnosis is accurately made by including a functional test, NERD patients respond to PPI therapy in a similar way to those with erosive disease. Although not as frequent as previously suggested, however, PPI-refractory heartburn does exist. Some 20% (range: 15-27%) of correctly diagnosed and appropriately treated patients do not respond to PPI treatment at standard doses. Although the pathophysiology underlying PPI failure in GERD is complex and likely multifactorial, acid (be it the sole component of refluxate or not) still remains a major causative factor. A better and more predictable form of acid suppression should therefore be pursued.

Evaluation of clinical outcome after laparoscopic antireflux surgery in clinical practice: still a controversial issue

Background. Laparoscopic antireflux surgery has shown to be effective in controlling gastroesophageal reflux (GERD). Yet, a universally accepted definition and evaluation for treatment success/failure in GERD is still controversial. The purpose of this paper is to assess if and how the outcome variables used in the different studies could possibly lead to an homogeneous appraisal of the limits and indications of LARS. Methods. We analyzed papers focusing on the efficacy and outcome of LARS and published in English literature over the last 10 years. Results. Symptoms scores and outcome variables reported are dissimilar and not uniform. The most consistent parameter was patient's satisfaction (mean satisfaction rate: 88.9%). Antireflux medications are not a trustworthy outcome index. Endoscopy and esophageal manometry do not appear very helpful. Twenty-four hours pH metry is recommended in patients difficult to manage for recurrent typical symptoms. Conclusions. More uniform symptoms scales and quality of life tools are needed for assessing the clinical outcome after laparoscopic antireflux surgery. In an era of cost containment, objective evaluation tests should be more specifically addressed. Relying on patient's satisfaction may be ambiguous, yet from this study it can be considered a practical and simple tool.

Post-fundoplication contrast studies: is there room for improvement?

OBJECTIVE

Since the mid-1990s, laparoscopic fundoplication for gastro-oesophageal reflux disease has become the surgical procedure of choice. Several surgical groups perform routine post-operative contrast studies to exclude any (asymptomatic) anatomical abnormality and to expedite discharge from hospital. The purpose of this study was to determine the accuracy and interobserver reliability for surgeons and radiologists in contrast study interpretation.

METHODS

11 surgeons and 13 radiologists (all blinded to outcome) retrospectively reviewed the contrast studies of 20 patients who had undergone a laparoscopic fundoplication. Each observer reported on fundal wrap position, leak or extravasation of contrast and contrast hold-up at the gastro-oesophageal junction (on a scale of 0-4). A κ coefficient was used to evaluate interobserver reliability.

RESULTS

Surgeons were more accurate than radiologists in identifying normal studies (specificity = 91.6% vs 78.9%), whereas both groups had similar accuracy in identifying abnormal studies (sensitivity = 82.3% vs 85.2%). There was higher agreement amongst surgeons than amongst radiologists when determining wrap position (κ = 0.65 vs 0.54). Both groups had low agreement when classifying a wrap migration as partial or total (κ = 0.33 vs 0.06). Radiologists were more likely to interpret the position of the wrap as abnormal (relative risk = 1.25) while surgeons reported a greater degree of hold-up of contrast at the gastro-oesophageal junction (mean score = 1.17 vs 0.86).

CONCLUSION

Radiologists would benefit from more information about the technical details of laparoscopic anti-reflux surgery. Standardised protocols for performing post-fundoplication contrast studies are needed.

Novel approaches to inhibition of gastric acid secretion

The gastric H,K-adenosine triphosphatase (ATPase) is the primary target for treatment of acid-related diseases. Proton pump inhibitors (PPIs) are weak bases composed of two moieties, a substituted pyridine with a primary pK(a) of about 4.0 that allows selective accumulation in the secretory canaliculus of the parietal cell, and a benzimidazole with a second pK(a) of about 1.0. Protonation of this benzimidazole activates these prodrugs, converting them to sulfenic acids and/or sulfenamides that react covalently with one or more cysteines accessible from the luminal surface of the ATPase. The maximal pharmacodynamic effect of PPIs as a group relies on cyclic adenosine monophosphate-driven H,K-ATPase translocation from the cytoplasm to the canalicular membrane of the parietal cell. At present, this effect can only be achieved with protein meal stimulation. Because of covalent binding, inhibitory effects last much longer than their plasma half-life. However, the short dwell-time of the drug in the blood and the requirement for acid activation impair their efficacy in acid suppression, particularly at night. All PPIs give excellent healing of peptic ulcer and produce good, but less than satisfactory, results in reflux esophagitis. PPIs combined with antibiotics eradicate Helicobacter pylori, but success has fallen to less than 80%. Longer dwell-time PPIs promise to improve acid suppression and hence clinical outcome. Potassium-competitive acid blockers (P-CABs) are another class of ATPase inhibitors, and at least one is in development. The P-CAB under development has a long duration of action even though its binding is not covalent. PPIs with a longer dwell time or P-CABs with long duration promise to address unmet clinical needs arising from an inability to inhibit nighttime acid secretion, with continued symptoms, delayed healing, and growth suppression of H. pylori reducing susceptibility to clarithromycin and amoxicillin. Thus, novel and more effective suppression of acid secretion would benefit those who suffer from acid-related morbidity, continuing esophageal damage and pain, nonsteroidal anti-inflammatory drug-induced ulcers, and nonresponders to H. pylori eradication.

Short and long-term PPI treatment for GERD. Do we need more-potent anti-secretory drugs?

Because the reflux of the acidic gastric content into the esophagus plays a major role in the pathogenesis of symptoms of GERD and lesions of erosive esophagitis, acid suppression with a proton pump inhibitor (PPI) is currently the mainstay of anti-reflux therapy. There is a strong correlation between the degree of acid suppression provided by a given drug and its efficacy. The superiority of PPIs over other drugs (antacids, prokinetics and H(2)-receptor antagonists) has now been established beyond doubt, both for short- and long-term treatment. However, there are still some unmet therapeutic needs in GERD; hence, patients with non-erosive reflux disease (NERD) are less responsive to PPIs than those with erosive esophagitis. Moreover, the efficacy of PPIs in patients with atypical symptoms is frequently limited to the relief of associated heartburn or regurgitation. With respect to safety, although most studies on short- and long-term PPI use have provided reassuring data, recent reports have drawn attention to potential side effects or drug-drug interference. Better healing rates in the most severe forms of esophagitis, or a faster onset of symptom relief, may require optimization of acid suppressive therapy with regard to the daily course of acid secretion, especially during the night. Different pharmacological approaches can be considered, with the ultimate goals of achieving faster, stronger and more-sustained acid inhibition. How a better pharmacological profile may translate into clinical benefit should now be tested in appropriate, controlled studies.