Functional heartburn: what it is and how to treat it

Untangling Nonerosive Reflux Disease From Functional Heartburn

Heartburn is a common symptom in clinical practice, but as many as 70% of patients have normal findings from upper endoscopy. Most of these patients have nonerosive reflux disease (NERD) or functional esophageal disorders. NERD is the most common phenotype of gastroesophageal reflux disease, and functional heartburn is the most common cause for refractory heartburn. In patients with NERD, symptoms arise from gastroesophageal reflux and esophageal hypersensitivity, whereas in patients with functional heartburn, symptoms result from esophageal hypersensitivity. A diagnosis of NERD requires endoscopy and reflux testing, whereas a diagnosis of functional heartburn also requires esophageal manometry. NERD is treated most commonly with medical, endoscopic, and surgical antireflux approaches, whereas functional heartburn as well as NERD can be treated with neuromodulators, psychological intervention, and complementary medicine options.

Decreased Plasma BDNF Levels of Patients with Somatization Disorder

OBJECTIVE

Brain-derived neurotrophic factor (BDNF), one of the most abundant and important neurotrophins, is known to be involved in the development, survival, maintenance, and plasticity of neurons in the nervous system. Some studies have suggested that BDNF may play a role in the pathophysiology of several psychiatric illnesses such as depression and schizophrenia. Similarly, it is likely that the alteration of BDNF may be associated with the neuro-modulation that contributes to the development of somatization disorder.

METHODS

The purpose of this study was to determine whether there is an abnormality of plasma BDNF levels in patients with somatization disorder, and to analyze the nature of the alteration after pharmacotherapy using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

The plasma BDNF levels of the patients with a somatization disorder were significantly lower compared with those of the control volunteers (83.61±89.97 pg/mL vs. 771.36±562.14 pg/mL); moreover, the plasma BDNF levels of those patients who received an antidepressant were significantly increased after the treatment (118.13±91.45 pg/mL vs. 72.92±88.21 pg/mL).

CONCLUSION

These results suggest that BDNF may play a role in the pathophysiology of somatization disorder.

Clinical potential of eluxadoline in the treatment of diarrhea-predominant irritable bowel syndrome

Diarrhea-predominant irritable bowel syndrome (IBS-D) belongs to the group of functional gastrointestinal disorders and is characterized by abdominal pain in conjunction with diarrhea. The incidence of IBS-D is currently increasing, leading to a heavy economic burden for patients and health care systems worldwide. Recent studies suggest eluxadoline as an attractive new tool for the treatment of patients with IBS-D. Eluxadoline is an orally active μ- and κ-opioid receptor agonist and δ-opioid receptor antagonist, with powerful antidiarrheal and analgesic activity. Eluxadoline is believed to act locally in the enteric nervous system, and has no adverse effects in the central nervous system. In this review, we discuss the most recent findings on the mechanism of action of eluxadoline and the results of the clinical trials in patients with IBS-D. We also discuss possible side effects and analyze the potential of eluxadoline to be used in the treatment of IBS-D.

The Proton Pump Inhibitor Non-Responder: A Clinical Conundrum

Gastroesophageal reflux disease (GERD) is a highly prevalent chronic condition where in stomach contents reflux into the esophagus causing symptoms, esophageal injury, and subsequent complications. Proton pump inhibitors (PPI) remain the mainstay of therapy for acid suppression. Despite their efficacy, significant proportions of GERD patients are either partial or non-responders to PPI therapy. Patients should be assessed for mechanisms that can lead to PPI failure and may require further evaluation to investigate for alternative causes. This monograph will outline a diagnostic approach to the PPI non-responder, review mechanisms associated with PPI failure, and discuss therapeutic options for those who fail to respond to PPI therapy.

New therapies for non-cardiac chest pain

After excluding a cardiac cause, potent anti-reflux therapy should be administered to patients with non-cardiac chest pain since gastroesophageal reflux disease (GERD) is the most common underlying mechanism of this disorder. If GERD is an unlikely cause of patient's symptoms, an esophageal motor disorder should be excluded. Spastic motility disorders can be treated with a smooth muscle relaxant (such as calcium channel blocker, nitrate, or phosphodiesterase 5 inhibitors). Alternatively, spastic motility disorders may respond to anti-spasmodics, pain modulators, botulinum toxin injection into the distal esophagus, and/or surgery. Patients with functional chest pain have recently seen an expanded treatment armamentarium including medications such as trazadone, tricyclic anti-depressants, selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, pregabalin, and/or ramelteon.

Gastroesophageal reflux symptoms not responding to proton pump inhibitor: GERD, NERD, NARD, esophageal hypersensitivity or dyspepsia?

Gastroesophageal reflux (GER) is a common gastrointestinal process that can generate symptoms of heartburn and chest pain. Proton pump inhibitors (PPIs) are the gold standard for the treatment of GER; however, a substantial group of GER patients fail to respond to PPIs. In the past, it was believed that acid reflux into the esophagus causes all, or at least the majority, of symptoms attributed to GER, with both erosive esophagitis and nonerosive outcomes. However, with modern testing techniques it has been shown that, in addition to acid reflux, the reflux of nonacid gastric and duodenal contents into the esophagus may also induce GER symptoms. It remains unknown how weakly acidic or alkaline refluxate with a pH similar to a normal diet induces GER symptoms. Esophageal hypersensitivity or functional dyspepsia with superimposed heartburn may be other mechanisms of symptom generation, often completely unrelated to GER. Detailed studies investigating the pathophysiology of esophageal hypersensitivity are not conclusive, and definitions of the various disease states may overlap and are often confusing. The authors aim to clarify the pathophysiology, definition, diagnostic techniques and medical treatment of patients with heartburn symptoms who fail PPI therapy.

Effect of nortriptyline on brain responses to painful esophageal acid infusion in patients with non-erosive reflux disease

BACKGROUND

Non-erosive reflux disease (NERD) patients generally present with heartburn as the main symptom. Antidepressants might help to relieve heartburn by acting on the esophagus-brain axis. We aimed to assess the effect of nortriptyline on behavioral and brain responses to painful esophageal acid infusion in NERD patients evaluated with functional magnetic resonance imaging (fMRI).

METHODS

In a randomized double-blind crossover design, 20 NERD patients off proton pump inhibitors (36.1 ± 9.3 years, 75% women) were assigned to 21 days of nortriptyline and placebo, in counterbalanced order, with a 21 days washout period in between both treatment periods. Changes in acid-induced brain response on fMRI and heartburn perception were assessed and at the end of each treatment.

KEY RESULTS

Nortriptyline significantly reduced the acid-induced brain response in prefrontal cortex (median [IQR]: -1.9 [-4.5 to -0.1] vs -0.3 [-2.5 to 2.3]; p = 0.050), caudate (-3.0 [-5.1 to -0.01] vs 0.48 [-1.9 to 3.1]; p = 0.029), insula (-2.4 [-4.8 to -0.6] vs -0.2 [-1.5 to 1.5]; p = 0.029), cingulate (-4.2 [-8.8 to -0.1] vs -0.6 [-1.8 to 3.0]; p = 0.017), and hippocampus (-2.7 [-6.0 to 0.5] vs -0.04 [-2.3 to 1.9]; p = 0.006) in comparison with placebo. However, there was no significant difference between nortriptyline and placebo in clinical outcomes and side effects.

CONCLUSIONS & INFERENCES

Nortriptyline decreased the brain response to esophageal acid infusion more markedly than placebo, but without clinical significance.

New and future drug development for gastroesophageal reflux disease

Medical therapy remains the most popular treatment for gastroesophageal reflux disease (GERD). Whilst interest in drug development for GERD has declined over the last few years primarily due to the conversion of most proton pump inhibitor (PPI)'s to generic and over the counter compounds, there are still numerous areas of unmet needs in GERD. Drug development has been focused on potent histamine type 2 receptor antagonist's, extended release PPI's, PPI combination, potassium-competitive acid blockers, transient lower esophageal sphincter relaxation reducers, prokinetics, mucosal protectants and esophageal pain modulators. It is likely that the aforementioned compounds will be niched for specific areas of unmet need in GERD, rather than compete with the presently available anti-reflux therapies.

[Functional heartburn--update 2013]

Functional heartburn is a frequent disease which should be considered when heartburn does not respond to proton pump inhibitor (PPI) treatment. Functional heartburn is defined in the Rome-III-criteria. Differential diagnoses like gastroesophageal reflux disease (GERD), non erosive reflux disease (NERD) and hypertensive esophagus are diagnosed employing an endoscopy and a 24h-pH-study. Since clinical trials are lacking, treatment approaches are empirical. Successful treatment includes adequate information of the patient, identification of the cardinal symptom and setting of realistic goals.

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.

Structured management strategy based on the Gastro-oesophageal Reflux Disease (GERD) Questionnaire (GerdQ) vs. usual primary care for GERD: pooled analysis of five cluster-randomised European studies

BACKGROUND

Response to treatment among primary care patients with gastro-oesophageal disease (GERD) is variable.

AIM

The GERD Management Project (GMP) evaluated the effectiveness of a structured management approach to GERD vs. standard treatment (usual care).

METHODS

Data from five cluster-randomised clinical trials in adult primary care patients with symptoms of GERD were pooled. The structured pathway was based on the self-administered GERD Questionnaire (GerdQ) and was compared with standard treatment.

RESULTS

1734 patients were enrolled (structured treatment, n=834; standard treatment, n=900). The difference in the mean GerdQ score change from baseline favoured the structured pathway (-0.61; 95% CI: -0.88, -0.34; p<0.001). The odds ratio for an indication for treatment revision at the end of follow-up (structured vs. standard treatment) was 0.39 (95% CI: 0.29, 0.52; p=0.001).

CONCLUSIONS

Management of primary care patients with GERD can be improved by systematic stratification of patients using a patient management tool such as the GerdQ.

Quantitative assessment and characterization of visceral hyperalgesia evoked by esophageal balloon distention and acid perfusion in patients with functional heartburn, nonerosive reflux disease, and erosive esophagitis

BACKGROUND AND OBJECTIVES

The role of esophageal hypersensitivity in functional heartburn (FH) with negative pH test, negative symptom index, and the proton pump inhibitor (PPI) failure has not been established. The aim of this study was to investigate the characterization of visceral hyperalgesia evoked by esophageal balloon distention and acid perfusion in patients with FH, nonerosive reflux disease, and erosive esophagitis and further characterize the pathophysiologic mechanism of FH.

METHODS

A total of 21 FH patients (with esophageal acid exposure <3.1% and a symptom index<50% and nonresponse to a therapeutic trial with proton pump inhibitors, 25 Nonerosive reflux disease (NERD) patients (with esophageal acid exposure>4%), 23 erosive esophagitis (EE) patients (LA grade B to D), and 18 healthy controls were recruited in the study. Mechanosensitivity including the initial perception threshold (IPT) and pain threshold (PT) was evaluated by using a Barostat with a double-random staircase distension protocol. Chemosensitivity was graded along a visual analog scale after perfusion of saline and 0.1 N HCl.

RESULTS

The baseline IPTs and PTs were all lower in patients with FH, NERD, and EE than in the controls (all P<0.01). In addition, the baseline PT in FH patients was significantly lower than those in NERD (P=0.015) and EE patients (P<0.001). After acid perfusion, the mean symptom intensity scores were significantly greater in patients with FH, NERD, and EE than those in the controls (all P<0.001). The postacid perfusion IPTs in patients with FH, NERD, and EE were all significantly lower than the corresponding baseline values (all P<0.01). The PTs in FH (P=0.026) and EE patients (P<0.001) were significantly lower than the corresponding baseline values. Moreover, the postacid perfusion PT was significantly lower in FH patients than in NERD patients (P<0.001).

CONCLUSIONS

FH patients are more sensitive to mechanical or chemical stimuli than NERD patients. Sensitization of esophageal acid-sensitive chemoreceptors may exert a significant influence on the pressure-sensitive mechanoreceptors, and there is the cooperative interaction in the process of esophageal visceral hyperalgesia.