Capsaicin-Sensitive Vagal Afferent Nerve-Mediated Interoceptive Signals in the Esophagus

Heartburn and non-cardiac chest pain are the predominant symptoms in many esophageal disorders, such as gastroesophageal reflux disease (GERD), non-erosive reflux disease (NERD), functional heartburn and chest pain, and eosinophilic esophagitis (EoE). At present, neuronal mechanisms underlying the process of interoceptive signals in the esophagus are still less clear. Noxious stimuli can activate a subpopulation of primary afferent neurons at their nerve terminals in the esophagus. The evoked action potentials are transmitted through both the spinal and vagal pathways to their central terminals, which synapse with the neurons in the central nervous system to induce esophageal nociception. Over the last few decades, progress has been made in our understanding on the peripheral and central neuronal mechanisms of esophageal nociception. In this review, we focus on the roles of capsaicin-sensitive vagal primary afferent nodose and jugular C-fiber neurons in processing nociceptive signals in the esophagus. We briefly compare their distinctive phenotypic features and functional responses to mechanical and chemical stimulations in the esophagus. Then, we summarize activation and/or sensitization effects of acid, inflammatory cells (eosinophils and mast cells), and mediators (ATP, 5-HT, bradykinin, adenosine, S1P) on these two nociceptive C-fiber subtypes. Lastly, we discuss the potential roles of capsaicin-sensitive esophageal afferent nerves in processing esophageal sensation and nociception. A better knowledge of the mechanism of nociceptive signal processes in primary afferent nerves in the esophagus will help to develop novel treatment approaches to relieve esophageal nociceptive symptoms, especially those that are refractory to proton pump inhibitors.

Fragments of e-Cadherin as Biomarkers of Non-erosive Reflux Disease

BACKGROUND

Approximately, 20% of patients with heartburn and normal endoscopic findings do not symptomatically improve on proton pump inhibitor (PPI) therapy making diagnosis and treatment uncertain. A biomarker distinguishing PPI-responsive from PPI-refractory heartburn is desirable.

AIMS

We performed a pilot study assessing whether carboxy(C)-terminal fragments (CTFs) of e-cadherin in esophageal biopsies or amino(N)-terminal fragments (NTFs) of e-cadherin in serum could serve this purpose.

METHODS

Twenty-nine patients with endoscopy-negative heartburn had esophageal biopsies for CTFs on Western blot and blood for serum NTFs on ELISA. All patients received dexlansoprazole 30 mg daily for 4 weeks, and heartburn was assessed by daily diary entry. Post-treatment blood samples were obtained for serum NTFs. A control group without GERD symptoms (n = 6) had biopsies for CTFs and a second control group (n = 20) blood serum for serum NTFs.

RESULTS

Twenty-seven of 29 patients (93.1%) with endoscopy-negative heartburn, but 0 of 6 controls, were positive for CTFs. All patients and controls had measureable serum NTFs, but mean NTFs were significantly higher in those with PPI-responsive heartburn compared to those with PPI-refractory heartburn and controls. Following treatment, 24 of 29 (82.8) patients had relief of heartburn, which associated with a decline in mean NTFs compared to controls. NTFs in PPI-refractory patients (n = 5) were similar to controls before and after PPI therapy.

CONCLUSIONS

When heartburn responds to PPI, elevated serum NTFs decline to normal. These data suggest that cleaved products of e-cadherin may serve as biomarkers of NERD. Further data are needed to assess and confirm this concept.

Esophageal Epithelial-Derived IL-33 Is Upregulated in Patients with Heartburn

Background

Interleukin-33 (IL-33) is a tissue-derived cytokine that is constitutively expressed in epithelial cells of tissues exposed to the environment and plays a role in sensing damage caused by inflammatory diseases. IL-33 acts as both a traditional cytokine and as a chromatin-associated nuclear factor in both innate and adaptive immunity. We recently showed that IL-33 in esophageal mucosa is upregulated in reflux esophagitis. However, IL-33 expression in patients with heartburn without mucosal injury and its relationship with intercellular space (ICS) have never been examined. We therefore examined the expression of cytokines and ICS in patients with heartburn.

Methods

The expression of IL-33 in the middle and distal esophageal mucosa of patients with heartburn without mucosal break and control samples was examined using real-time RT-PCR and immunofluorescence. The mRNA expression of IL-6, IL-8, MCP-1, and RANTES, and ICS was also analyzed.

Results

IL-33 expression and the mean ICS were significantly increased in the mucosa of patients with heartburn compared to that of the control. IL-33 and ICS were not different between the patients who were taking a PPI and those who were not. The upregulated IL-33 expression in the heartburn group was located in the nuclei of the basal cell layer. Although IL-6, IL-8, MCP-1 and RANTES levels were not different between control and patients with heartburn samples, IL-33 mRNA levels were still significantly correlated with IL-6, IL-8, or MCP-1 mRNA levels.

Conclusion

Nuclear IL-33 is upregulated in patients with heartburn. Upregulated IL-33 in heartburn patients is related to the symptoms.

Challenges of correlating pH change with relief of clinical symptoms in gastro esophageal reflux disease: a phase III, randomized study of Zegerid versus Losec

Background

Zegerid (on demand immediate-release omeprazole and sodium bicarbonate combination therapy) has demonstrated earlier absorption and more rapid pH change compared with Losec (standard enteric coated omeprazole), suggesting more rapid clinical relief of heartburn. This Phase III, multicenter, double-blind, double-dummy, randomized study assessed the clinical superiority of Zegerid versus Losec for rapid relief of heartburn associated with gastro-esophageal reflux disease (GERD).

Methods

Patients with a history of frequent (2 3 days/week) uncomplicated GERD, were randomized to receive Zegerid (20mg) or Losec (20mg) with corresponding placebo. Study medication was self-administered on the first episode of heartburn, and could be taken for up to 3 days within a 14 day study period. Heartburn severity was self assessed up to 180 minutes post dose (9 point Likert scale). Primary endpoint was median time to sustained response (≥3 point reduction in heartburn severity for ≥45 minutes).

Results

Of patients randomized to Zegerid (N=122) or Losec (N=117), 228/239 had recorded ≥1 evaluable heartburn episodes and were included in the modified intent-to-treat population. No significant between-group differences were observed for median time to sustained response (60.0 vs. 52.2 minutes, Zegerid [N=117] and Losec [N=111], respectively), sustained partial response (both, 37.5 minutes) and sustained total relief (both, 105 minutes). Significantly more patients treated with Zegerid reached sustained total relief within 0–30 minutes post dose in all analysis sets (p<0.05). Both treatments were well tolerated and did not raise any safety concerns.

Conclusions

Superiority of Zegerid over Losec for rapid heartburn relief was not demonstrated; both treatments were equally effective however the rapid onset of action of Losec was unexpected. Factors, including aspects of study design may have contributed to this. This study supports previously reported difficulty in correlating intra-gastric pH change with clinical effect in GERD therapy, highlighting the significance of several technical considerations for studies of this type.

Trial registration

ClinicalTrials.gov NCT01493089

Increased acid responsiveness in vagal sensory neurons in a guinea pig model of eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is characterized with eosinophils and mast cells predominated allergic inflammation in the esophagus and present with esophageal dysfunctions such as dysphagia, food impaction, and heartburn. However, the underlying mechanism of esophageal dysfunctions is unclear. This study aims to determine whether neurons in the vagal sensory ganglia are modulated in a guinea pig model of EoE. Animals were actively sensitized by ovalbumin (OVA) and then challenged with aerosol OVA inhalation for 2 wk. This results in a mild esophagitis with increases in mast cells and eosinophils in the esophageal wall. Vagal nodose and jugular neurons were disassociated, and their responses to acid, capsaicin, and transient receptor potential vanilloid type 1 (TRPV1) antagonist AMG-9810 were studied by calcium imaging and whole cell patch-clamp recording. Compared with naïve animals, antigen challenge significantly increased acid responsiveness in both nodose and jugular neurons. Their responses to capsaicin were also increased after antigen challenge. AMG-9810, at a concentration that blocked capsaicin-evoked calcium influx, abolished the increase in acid-induced activation in both nodose and jugular neurons. Vagotomy strongly attenuated those increased responses of nodose and jugular neurons to both acid and capsaicin induced by antigen challenge. These data for the first time demonstrated that prolonged antigen challenge significantly increases acid responsiveness in vagal nodose and jugular ganglia neurons. This sensitization effect is mediated largely through TRPV1 and initiated at sensory nerve endings in the peripheral tissues. Allergen-induced enhancement of responsiveness to noxious stimulation by acid in sensory nerve may contribute to the development of esophageal dysfunctions such as heartburn in EoE.

Dietary nitrate may have a role in development of gastro-esophageal reflux disease

BACKGROUND

Gastro-esophageal reflux disease (GERD) has become very common in the past three decades. The reason for this, as well as its exact pathophysiologic mechanisms are yet unknown. In this ecologic study we assessed the relation between water nitrate content and prevalence of GERD in Tehran, Iran.

METHODS

We determined the prevalence of acid regurgitation, heartburn or any of them occurring on a frequent (at least weekly) or infrequent basis in areas with different water nitrate. The areas for nitrate were defined as below: <50 mg nitrate/L, 50-74 mg/L, 75-100 mg/L, and >100 mg/L. Frequency of each symptom was assessed in each area and compared. Adjustment for age, sex, education, NSAID-consumption, BMI, smoking, history of GERD in first degree relatives and spouse was done in a multivariate model.

RESULTS

People living in areas with water nitrate content more than 100mg/L had a higher chance of suffering from frequent AR than those living in areas with water nitrate less than 100mg/L (25.5% vs. 12.0%, OR: 2.53, 95% CI: 1.36-4.73, P=0.006). After adjustment for the named factors, the relationship remained significant (OR: 3.65, 95% CI: 1.32-10.09). The relation for frequent heartburn or infrequent symptoms was not significant.

CONCLUSION

In this ecologic study, we found a relation between experiencing frequent AR and drinking or cooking with water containing more than 100mg nitrate/L. Considering our current knowledge, if we put dietary nitrate into the puzzle of increased prevalence and/or pathophysiology of GERD, it can theoretically answer several questions. Hence we propose a nitrate-hypothesis for GERD pathogenesis.

Comparisons of the distribution of oesophageal acid exposure throughout the sleep period among the different gastro-oesophageal reflux disease groups

BACKGROUND

Nocturnal gastro-oesophageal reflux diseases (GERD) can lead to oesophageal mucosal injury and extra-oesophageal complications.

AIM

To compare distribution of oesophageal acid exposure during sleep time among patients with non-erosive reflux disease and abnormal pH test (NERD-positive), erosive oesophagitis (EO) and Barrett's oesophagus (BO).

METHODS

Patients underwent endoscopy followed by 24-h oesophageal pH testing. Oesophageal acid exposure was assessed every 2 h of the sleep period (0-2, 2-4, 4-6 and 6-8 h). Each period of 2 h was evaluated for acid reflux parameters. All groups were matched by age, time from last meal and duration of sleep time.

RESULTS

Thirty-eight patients were enrolled (NERD-positive, 16; EO, 1.4; and BO, 8). All GERD groups demonstrated higher oesophageal acid exposure in the first vs. second half of the sleep period as determined by percent time pH <4 (BO: 34.7 vs.11.6, EO: 13.5 vs. 6.9, NERD-positive: 8.8 vs. 2.5, all P < 0.01). In general, patients with BO had a significantly higher distribution of oesophageal acid exposure than those with NERD-positive and EO.

CONCLUSIONS

Oesophageal acid exposure generally declines throughout the sleep period regardless of GERD group, but BO patients demonstrated the greatest decline during the sleep period.

Reflux events and sleep: are we vulnerable?

This review addresses the changes in the physiologic responses to esophageal acid contact that occur during sleep. The importance of these changes is addressed as they pertain to the development of esophagitis and other complications of gastroesophageal reflux. Sleep results in physiologic changes that impair esophageal acid clearance, thereby creating a vulnerability to the complications of reflux. These complications are generally considered secondary to prolonged acid mucosal contact. Sleep-related reflux also produces a disruption of sleep, which may result in clinical complaints of sleep disturbance and significant daytime consequences, such as sleepiness and diminished work performance. The significance of these sleep-related findings is addressed as they relate to the diagnosis and treatment of gastroesophageal reflux disease.

The extent of oesophageal acid exposure overlap among the different gastro-oesophageal reflux disease groups

BACKGROUND

Studies have demonstrated that patients with Barrett's oesophagus have the highest oesophageal acid exposure profile, followed by erosive oesophagitis and non-erosive reflux disease patients, but the exact extent of overlap remains unknown.

AIM

To determine the extent of overlap in oesophageal acid exposure among the different gastro-oesophageal reflux disease groups.

METHODS

A total of 121 patients with gastro-oesophageal reflux disease underwent an upper endoscopy and were classified as having Barrett's oesophagus, erosive oesophagitis and non-erosive reflux disease-all (non-erosive reflux disease-positive and functional heartburn). Subsequently, patients underwent pH testing and overlap in oesophageal acid exposure among the different gastro-oesophageal reflux disease groups was determined.

RESULTS

Of those enrolled, 24 had Barrett's oesophagus, 30 erosive oesophagitis and 28 were non-erosive reflux disease-positive. Mean oesophageal acid exposure time was 224.8 +/- 35, 134.3 +/- 21.9 and 141.3 +/- 19.8 min for Barrett's oesophagus, erosive oesophagitis and non-erosive reflux disease-positive respectively. Per cent overlap for total, upright and supine time between non-erosive reflux disease-positive and erosive oesophagitis was 47.4%, 64.7% and 81.8%, between Barrett's oesophagus and erosive oesophagitis was 47.8%, 40.7% and 24%, and between Barrett's oesophagus and non-erosive reflux disease-positive was 31.6%, 37.5% and 20.8% respectively.

CONCLUSIONS

Our study demonstrated a high oesophageal acid exposure overlap between patients with non-erosive reflux disease-positive and erosive oesophagitis, Barrett's oesophagus and erosive oesophagitis, as well as Barrett's oesophagus and non-erosive reflux disease-positive patients.

Patients with functional heartburn are more likely to report retrosternal discomfort during wireless pH monitoring

BACKGROUND

Although the wireless Bravo pH system is effective, some patients experience retrosternal sensations possibly caused by esophageal sensitivity that may complicate clinical application.

METHODS

Ambulatory pH of 40 consecutive patients with GERD who had erosive esophagitis or nonerosive reflux disease, were monitored for 2 days with the Bravo system. Results were stratified and compared on the basis of self-awareness of the intraesophageal capsule.

RESULTS

Pathologic acid reflux was diagnosed in 20 patients and normal reflux was diagnosed in 20 patients. Seventeen patients (42.5%) reported retrosternal discomfort, and 12 of them (70.6%) had normal reflux. Patients with retrosternal discomfort were less likely to have moderate endoscopic esophagitis, i.e., Los Angeles classification grades B, C, and D endoscopic esophagitis (p = 0.006), and were less likely to have significantly elevated esophageal acid exposure (p = 0.0036) than those who did not perceive the discomfort. Reported discomfort was not associated with age, gender, or the presence of endoscopic esophagitis.

CONCLUSIONS

The negative correlation between Bravo-capsule-induced retrosternal discomfort and esophageal-acid exposure indicates modified mechanical afferent nerve function after long-term acid stimulation. Capsule-induced retrosternal discomfort in the presence of normal acid exposure suggests functional heartburn.

Relief of reflux symptoms after endoscopic gastroplication may be associated with reduced esophageal Acid sensitivity: a pilot study

BACKGROUND AND STUDY AIMS

Although the new endoscopic techniques for the treatment of gastroesophageal reflux disease (GERD) lead to marked clinical benefit, the underlying mechanism of this is unknown.

MATERIALS AND METHODS

In this prospective study, the effect of endoscopic gastroplication was investigated in six patients with GERD, who were assessed before and 4 weeks after treatment. The effect on reflux symptoms, quality of life, proton pump inhibitor (PPI) consumption, reflux esophagitis, acid exposure, esophageal motility, lower esophageal sphincter pressure (LESP), and gastric emptying was measured. Esophageal acid sensitivity before and after treatment was investigated using a standardized acid provocation test, and compared with that of six age- and sex-matched healthy controls.

RESULTS

Significant clinical benefit and discontinuation of PPI consumption after gastroplication was seen. Among the objectively measured parameters, only acid exposure was significantly reduced and gastric emptying significantly delayed. However, acid exposure remained pathologically high. Esophageal acid sensitivity was significantly reduced. The induction of heartburn and/or pain was abolished in four patients after gastroplication. In two patients the intensity of heartburn/pain was significantly reduced by 40 % or 60 %, and the time to provoke heartburn/pain significantly prolonged by 40% or 100%.

CONCLUSION

These preliminary data suggest that the decrease of esophageal sensitivity to acid after endoscopic gastroplication is part of the mechanism responsible for the reduction of reflux symptoms.

Lack of association between esophageal acid sensitivity detected by prolonged pH monitoring and Bernstein testing

OBJECTIVES

Heartburn, a common medical symptom, is thought to be the result of acid reflux into the esophagus. Perfusion of the esophagus with exogenous acid (Bernstein test) in susceptible individuals causes heartburn. Temporal correlation between heartburn and pH drop in the esophagus from endogenous acid, as reflected by a positive symptom index (SI), provides further evidence of a correlation between acid in the esophagus and heartburn. We tested the relationship between heartburn and acid in the esophagus by determining the SI and Bernstein test results in the same individual.

METHODS

Ninety-three patients with heartburn underwent 24-h pH monitoring and Bernstein testing. A Bernstein score that included the severity of heartburn and the time of heartburn onset during Bernstein test was calculated. The relationship between SI, Bernstein test, and Bernstein score was determined.

RESULTS

Fifty-eight patients reported symptoms during the prolonged pH recording. A positive SI was detected in 27 patients. Forty-nine patients had a positive Bernstein test. There was no correlation between the patients with a positive SI and positive Bernstein test results. There was no correlation between SI and Bernstein score. A positive Bernstein test within 5 min of acid infusion did not predict heartburn during spontaneous reflux episodes of >/=5 min.

CONCLUSIONS

The lack of association between symptoms induced by acid perfusion of the esophagus compared with symptoms following spontaneous reflux in the same individual suggests that the heartburn following acid perfusion and spontaneous heartburn are induced by different stimuli.

Heartburn: cardiac potassium channels involved in parietal cell acid secretion

Hydrochloric acid is produced in parietal cells of the gastric glands by an H(+)/K(+)-ATPase. This proton pump couples the outwards movement of H(+) to the inwards movement of K(+) thus requiring the presence of luminal K(+) to operate. To maintain the activity of the pump, K(+) recirculates over the apical membrane via conductive pathways, the molecular nature of which has been identified in the past few years. This review gives a short overview about the recent advances in the understanding of the role of K(+) channels in the process of parietal cell H(+) secretion and focuses on the identification of KCNQ1/KCNE2 K(+) channel as the molecular correlate of the parietal cell apical potassium conductance.

Clinical effectiveness of a new antacid chewing gum on heartburn and oesophageal pH control

BACKGROUND

Oesophageal acid neutralization with antacids depends on the duration of oesophageal antacid exposure and acid neutralizing capacity. A gum that releases antacid as it is chewed could take advantage of both mechanisms to enhance heartburn relief.

METHODS

Twenty-four subjects were crossed over to four regimens: placebo, chewable antacid tablets (1000 mg CaCO3), lower dose gum (600 mg CaCO3) and higher dose gum (900 mg CaCO3). A dual pH probe was placed, subjects ate a standardized provocative meal and self-dosed once as needed. Symptoms were recorded every 15 min using visual analogue and Likert scales.

RESULTS

SYMPTOMS

Both gums decreased heartburn compared to placebo for 120 min. Higher dose gum decreased heartburn more than chewable antacids up to 120 min post-dose. pH: Active chewable antacid and gums immediately increased oesophageal pH, with significant improvement 15-30 min post-dose.

SUMMARY

(i) both gums promptly decreased heartburn and elevated oesophageal pH; (ii) both gums provided sustained relief for 120 min; (iii) antacid gums provided faster and more prolonged symptom relief and pH control than chewable antacids.

CONCLUSIONS

Calcium carbonate gum effectively neutralizes oesophageal acidity and relieves symptoms following a meal, and is superior to chewable antacids in terms of the duration of heartburn relief.

Heartburn correlated to 24-hour pH monitoring and radiographic examination of the esophagus

OBJECTIVES

Study relationship of gastroesophageal reflux disease to findings on radiographic examination of the esophagus.

METHODS

We correlated heartburn (HB) in 360 patients (174 women; 186 men; mean age, 53 yr) to results of pH monitoring (pHM) and radiographic examination of the esophagus. Radiographic findings were categorized as normal (n = 129), hiatal hernia (HH) only (n = 173), reflux esophagitis (n = 50), or peptic stricture (n = 8) (ES; 58). Abnormal pHM was defined as total percentage of esophageal acid exposure time (pH < 4) of 6% or greater.

RESULTS

pHM was abnormal in 41 (31%) of 132 patients with HB versus 54 (24%) of 228 without the symptom (p > 0.05). Radiographic correlation showed abnormal pHM in only 21 (16%) of 129 patients with a normal esophagus, 52 (30%) of 173 with HH, and 22 (38%) of 58 with ES, which was significantly lower for those with a normal esophagus. In 132 patients with HB, those with normal esophagus had lower abnormal pHM (2 of 38; 5%) compared with patients with HH (24 of 64; 38%) or with ES (15 of 30; 50%) (p < 0.05). In the 228 patients without HB, abnormal pHM was found in 19 (21%) of 91 with a normal esophagus, 28 (26%) of 109 with HH, and 7 (25%) of 28 with ES (p > 0.05).

CONCLUSIONS

(1) pHM findings did not correlate with presence or absence of HB; (2) pHM is usually normal in patients with normal esophagus on RE; (3) pHM is also usually normal in patients with HB and normal esophagus on RE; and (4) pHM is often normal in patients with radiographic findings of reflux esophagitis or peptic stricture.

Nonprescription H2-receptor antagonists

OBJECTIVE

This article reviews the use of nonprescription histamine2-receptor antagonists (H2RAs) in the management of secretory disorders of the upper gastrointestinal tract.

DATA SOURCES

The scientific and consumer literature pertaining to the over-the-counter availability and therapeutic uses of H2RAs was reviewed.

STUDY SELECTION

References related to safety, efficacy, comparative efficacy with antacids, and economic impact of H2RA therapy were emphasized. Additional importance was placed on information describing the pharmacist's role in nonprescription H2RA therapy.

DATA EXTRACTION

Data from product package inserts as well as the scientific literature were extrapolated to provide information on indications, dosage and administration, adverse effects, drug interactions, and patient information.

DATA SYNTHESIS

The literature review focused on the relative role of these agents as an alternative to traditional nonprescription treatment of self-limiting gastrointestinal conditions as well as the advice and instructions that the patient should receive.

CONCLUSION

H2RAs represent a nonprescription option for the prevention and treatment of heartburn, acid indigestion, and sour stomach. They are effective and safe, but take longer to work and are more expensive than antacids. The availability of H2RAs without a prescription may reduce overall health care costs by decreasing the need for physician office visits. However, the pharmacist should counsel patients on the proper use of these products. In their role as primary care providers, pharmacists must evaluate whether the products will relieve a given patient's symptoms or whether the patient requires referral to another clinician (e.g., physician) for a more thorough examination and treatment.

Efficacy of a pectin-based anti-reflux agent on acid reflux and recurrence of symptoms and oesophagitis in gastro-oesophageal reflux disease

OBJECTIVE

Gastro-oesophageal reflux disease may be treated with a drug forming a floating neutral raft in the stomach. The pectin-based raft-forming anti-reflux agent Aflurax (Idoflux) was examined, first regarding reduction of oesophageal acid exposure, and next as to its efficacy as maintenance treatment in patients with healed oesophagitis.

DESIGN

Double-blind, placebo-controlled randomized clinical trials.

SETTING

Open access endoscopy unit.

PARTICIPANTS

Fourteen patients with erosive oesophagitis had measurement of acid exposure. Eighty-eight patients with healed erosive/ulcerative oesophagitis and relief of heartburn after pre-treatment with omeprazole received maintenance treatment.

INTERVENTIONS

Crossover 12-h oesophageal pH monitoring during Aflurax/placebo treatment. Maintenance treatment for up to 6 months with two tablets of Aflurax 1200 mg or placebo four times daily.

MAIN OUTCOME MEASURES

Percentage time pH less than 4 in 6 plus 6 h (upright + supine). Time to recurrence of moderate or severe heartburn (life table analysis).

RESULTS

The median (interquartile range) acid exposure times in the upright position were: 3.1% (1.6-13.0%) on Aflurax versus 6.7% (2.5-14.9%) on placebo (P = 0.10). In the supine position no difference was found (Aflurax 13.7%, placebo 13.2%). The time to recurrence of heartburn with Aflurax treatment was prolonged significantly; after 6 months the life table estimates were 48% of patients in remission on Aflurax versus 8% on placebo (P = 0.01). Following treatment, erosive oesophagitis was found in 17/34 on Aflurax versus 28/38 on placebo (P < 0.05).

CONCLUSION

Aflurax significantly delays recurrence of moderate or severe heartburn and erosive oesophagitis, when used as maintenance treatment. The acid exposure was not significantly reduced with pH monitoring.

Chocolate and heartburn: evidence of increased esophageal acid exposure after chocolate ingestion

Chocolate has been shown to decrease mean basal lower esophageal sphincter (LES) pressure, providing a rationale for the pathogenesis of chocolate-induced reflux symptoms. We assessed the relationship between chocolate ingestion and increased esophageal acid exposure using intraesophageal pH monitoring. Compared with ingestion of a dextrose control solution of similar volume, osmolality, and calories, postprandial ingestion of chocolate resulted in a significant increase in acid exposure in the first postprandial hour in patients with esophagitis. We conclude that this finding supports recommendations that patients with reflux esophagitis abstain from chocolate.