Influence of theophylline on gastro-oesophageal reflux and asthma

Gastroesophageal Reflux Disease and Asthma: A Narrative Review

Gastroesophageal reflux disease (GERD) is defined by retrograde reflux of gastric contents to the esophagus leading to various signs and symptoms that range from heartburn/regurgitation to the development of extraesophageal respiratory syndromes like asthma. Although a cause-effect relationship has been proposed, evidence suggests that these two entities share a complex mechanism that may be reciprocal to each other. The understanding of the underlying mechanisms is imperial due to the fact that asthmatic patients may benefit from reflux therapy with subsequent improvement in pulmonary function testing and quality of life. This study has revised available literature in order to provide evidence for a nexus between GERD and asthma based on clinical correlation, pathophysiology, and pharmacologic management.

Bronchodilators in subjects with asthma-related comorbidities

Asthma is often associated with different comorbidities such as cardiovascular diseases, depression, diabetes mellitus, dyslipidaemia, osteoporosis, rhinosinusitis and mainly gastro-oesophageal reflux disease and allergic rhinitis. Although bronchodilators play an important role in the treatment of asthma, there is no overall description of their impact on comorbid asthma, regardless of whether favourable or negative. This narrative review examines the potential effects of bronchodilators on comorbidities of asthma.

Risk of GERD with Diabetes Mellitus, Hypertension and Bronchial Asthma - A Hospital based Retrospective Cohort Study

INTRODUCTION

The rise in Gastro-Esophageal Reflux Disease (GERD) prevalence appears to have coincided with a simultaneous increase in the prevalence of diabetes mellitus, hypertension and bronchial asthma amongst the Indian population. Despite being evaluated extensively for their role as a risk factor for GERD, till date this relationship has remained a debatable one. Moreover, literature available on such studies conducted within Indian population remains scarce.

AIM

The aim of the present study was to examine the risk of developing GERD in patients suffering from diabetes mellitus, hypertension and asthma in a Southern Indian population. The present retrospective, triple cohort and hospital based study was conducted by accessing the patient records from the medical records department of a tertiary care hospital in Southern India.

MATERIALS AND METHODS

The patient's records were accessed from the year 2011 onwards. Relative Risk (RR) was calculated to determine the risk of development of GERD with every disease. Chi-square test was used to determine the statistical significance of the relationship between each disease and the development of GERD. A p-value of <0.05 was considered statistically significant.

RESULTS

In view of the time constraints as well as the limitations of the inclusion and exclusion criteria, data pertaining to only 40, 71 and 53 patients in Cohort 1 (diabetics), 2 (hypertensives) and 3 (bronchial asthmatics) respectively could be analyzed in the present study. The relative risk of GERD development was greater than 1 for patients belonging to Cohort 2 and 3, suggesting that the risk of GERD development is higher amongst hypertensives and asthmatics. Surprisingly, the diabetics (Cohort 1) were not associated with a high risk of GERD development. However, the relationship between any of the disease and GERD development was not statistically significant.

CONCLUSION

The present study found an increased risk of GERD development amongst patients suffering from hypertension and bronchial asthma, but not with diabetes mellitus.

Gastric Asthma: A Vagally-Mediated Disease

Many evidences show that bronchial asthma may be triggered or enhanced by gastroesophageal reflux (GER) even if standardized methods to detect this particular syndrome defined as “gastric asthma” are not available. The Bernstein test suitably modified was performed in 6 adult asthmatic outpatients when they were symptom-free. These subjects were also suffering from recurrent epigastric pain. The patients resulted positive to ultranebulized fog bronchial challenge and all had a moderate- severe alteration of the competency of the lower esophageal sphincter, shown by endoscopy. Functional lung parameters were significantly reduced after esophageal acidification when they were compared to basal values.

Is the linkage between GER and asthma important in clinical practice? In asthmatic patients GER represents an important trigger for broncoconstriction through a vagal mediated reflex. The modified Bernstein test represents a reproducible method and may be well used to identify “gastric asthma”, particularly when this picture is “silent”, less evident, or it is not rightly considered. Moreover, its recognition is very relevant to therapeutic problems, also when it is in a subclinical stage. In fact, many “excellent” drugs used for bronchial asthma treatment may have undesirable effects for the gastric tract causing abnormalities such as GER that is so damaging in the development of “gastric asthma”.

Extra-esophageal gastroesophageal reflux disease and asthma: understanding this interplay

Gastroesophageal reflux disease (GERD) is a condition that develops when there is reflux of stomach contents, which typically manifests as heartburn and regurgitation. These esophageal symptoms are well recognized; however, there are extra-esophageal manifestations of GERD, which include asthma, chronic cough, laryngitis and sinusitis. With the rising incidence of asthma, there is increasing interest in identifying how GERD impacts asthma development and therapy. Due to the poor sensitivity of endoscopy and pH monitoring, empiric therapy with proton pump inhibitors (PPIs) is now considered the initial diagnostic step in patients suspected of having GERD-related symptoms. If unresponsive, diagnostic testing with pH monitoring off therapy and/or impedance/pH monitoring on therapy, may be reasonable in order to assess for baseline presence of reflux with the former and exclude continued acid or weakly acid reflux with the latter tests. PPI-unresponsive asthmatics, without overt regurgitation, usually have either no reflux or causes other than GERD. In this group, PPI therapy should be discontinued. In those with GERD as a contributing factor acid suppressive therapy should be continued as well as optimally treating other etiologies requiring concomitant treatment. Surgical fundoplication is rarely needed but in those with a large hiatal hernia, moderate-to-severe reflux by pH monitoring surgery might be helpful in eliminating the need for high-dose acid suppressive therapy.

Causes of, and therapeutic approaches for, proton pump inhibitor-resistant gastroesophageal reflux disease in Asia

Proton pump inhibitors (PPIs) are the most widely used drugs for treatment of gastroesophageal reflux disease. However, approximately 20% of patients with reflux esophagitis and 40% of those with nonerosive reflux diseases complain of troublesome symptoms, even during treatment with PPIs. In patients with reflux esophagitis, dose escalation and co-administration with a histamine H(2)-receptor antagonist are potential approaches, since the major cause of PPI resistance is incomplete suppression of gastric acid secretion. On the other hand, for patients with nonerosive reflux disease, switching from PPIs to pain modulators is often necessary for improvement of symptoms, since 25% of patients with nonerosive reflux disease have symptoms not caused by gastroesophageal acid reflux. Therapeutic approaches for PPI-resistant patients with reflux esophagitis and nonerosive reflux diseases are considered according to pathogenesis.

The relationship between gastroesophageal reflux and asthma: an update

Asthma and gastroesophageal reflux disease (GERD) are both common conditions and, hence, they often coexist. However, asthmatics have been found to have a much greater prevalence of GERD symptoms than the general population. There remains debate regarding the underlying physiologic mechanism(s) of this relationship and whether treatment of GERD actually translates into improved asthma outcomes. Based on smaller trials with somewhat conflicting results regarding improved asthma control with treatment of GERD, current guidelines recommend a trial of GERD treatment for symptomatic asthmatics even without symptoms of GERD. However, recently a large multicenter trial demonstrated that the treatment of asymptomatic GERD with proton-pump inhibitors did not improve asthma control in terms of pulmonary function, rate of asthma exacerbations, asthma-related quality of life, or asthma symptom frequency. These data suggest empiric treatment of asymptomatic GERD in asthmatics is not a useful practice. This review article provides an overview of the epidemiology and pathophysiologic relationships between asthma and GERD as well as a summary of current data regarding links between treatment of GERD with asthma outcomes.

The effects of nebulized albuterol on esophageal function in asthmatic patients

PURPOSE

Albuterol reduces lower esophageal sphincter (LES) pressure in normal volunteers, although the effects of albuterol on esophageal function in asthmatic patients are not known. The aim of this study was to evaluate the effects of nebulized albuterol on lower esophageal function in asthmatic patients. Symptoms and a methacholine challenge test were used to identify asthmatic patients who were then enrolled in a prospective, randomized, placebo-controlled, double-blinded, crossover trial. Changes in esophageal function in response to nebulized albuterol or placebo were evaluated over two sessions spaced 1 week apart.

RESULTS

Albuterol induced a dose-dependent drop in lower esophageal sphincter basal pressure with a threshold dose as low as 2.5 mg. Albuterol did not affect the amplitude of esophageal contractions.

CONCLUSIONS

Nebulized albuterol induces a dose-dependent reduction in LES basal pressure in asthmatic patients. These effects raise the possibility that gastroesophageal reflux may occur after bronchodilator therapy.

The prevalence and risk factors of reflux esophagitis among adult Chinese population in Taiwan

BACKGROUND

Risk factors of reflux esophagitis among Chinese in Taiwan are at present not clear and the role of Helicobacter pylori infection in the development of reflux esophagitis is still controversial.

GOALS

The aim of this study was to examine the prevalence of reflux esophagitis, and to identify risk factors associated with reflux esophagitis in a multivariate context and to evaluate if H. pylori is a predictive factor for reflux esophagitis.

STUDY

A total of 482 physical check-up subjects who underwent upper gastrointestinal endoscopy were investigated. The severity of esophagitis was evaluated by Los Angeles classification. H. pylori status was assessed by serology.

RESULTS

Twelve percent (58/482) demonstrated reflux esophagitis with 87% of grade A or B. Of those with reflux esophagitis, 48.3% had reflux symptoms whereas 17.4% of those with reflux symptoms had reflux esophagitis. Univariate analysis identified hiatal hernia, male sex, smoking, alcohol drinking, and overweight as risk factors associated with reflux esophagitis. Multivariable logistic regression showed that hiatal hernia [odds ratio (OR)=12.2, 95% confidence interval (CI)=5.0-29.9, P<0.0001], male sex (OR=4.2, 95% CI=1.9-9.0, P<0.001), and chronic obstructive pulmonary disease sufferers (OR=3.4, 95% CI=1.1-10.9, P<0.05) were 3 independent risk factors for development of reflux esophagitis.

CONCLUSIONS

The prevalence of reflux esophagitis in Taiwanese is 12% and most are mild grade and free from reflux symptoms. Hiatus hernia, male sex, and chronic obstructive pulmonary disease are 3 independent risk factors for development of reflux esophagitis. H. pylori infection did not protect subjects from reflux esophagitis.

Extraesophageal manifestations of gastroesophageal reflux disease

Gastroesophageal reflux disease often presents as heartburn and acid reflux, the so-called "typical" symptoms. However, a subgroup of patients presents a collection of signs and symptoms that are not directly related to esophageal damage. These are known collectively as the extraesophageal manifestations of gastroesophageal reflux disease. Principal among such manifestations are bronchospasm, chronic cough and laryngitis, which are classified as atypical symptoms. These manifestations comprise a heterogeneous group. However, some generalizations can be made regarding all of the subgroups. First, although the correlation between gastroesophageal reflux disease and the extraesophageal manifestations has been well established, a cause-and-effect relationship has yet to be definitively elucidated. In addition, the main proposed pathogenic mechanisms of extraesophageal reflux are direct injury of the extraesophageal tissue (caused by contact with gastric acid) and the esophagobronchial reflex, which is mediated by the vagus nerve. Furthermore, gastroesophageal reflux disease might not be considered in the differential diagnosis of patients presenting only the atypical symptoms. In this article, we review the extraesophageal manifestations of gastroesophageal reflux disease, discussing its epidemiology, pathogenesis, diagnosis and treatment. We focus on the most extensively studied and well-established presentations.

Theophylline improves esophageal chest pain--a randomized, placebo-controlled study

BACKGROUND/AIM

The treatment of esophageal (noncardiac) chest pain is unsatisfactory and there is no approved therapy. A previous uncontrolled study suggested that theophylline may be useful. Our aims were to investigate the effects of theophylline on esophageal sensorimotor function and chest pain.

METHODS

In a double-blind study, sensory and biomechanical properties of the esophagus were assessed using impedance planimetry in 16 patients with esophageal hypersensitivity, after intravenous theophylline or placebo. In a second, randomized 4-wk crossover study, oral theophylline and placebo were administered to 24 patients with esophageal hypersensitivity. Frequency, intensity, and duration of chest pain episodes were evaluated.

RESULTS

After IV theophylline, chest pain thresholds (P=0.027) and esophageal cross-sectional area (P=0.03) increased and the esophageal wall became more distensible (P=0.04) compared with placebo. After oral theophylline, the number of painful days (P=0.03) and chest pain episodes (P=0.025), pain duration (P=0.002), and its severity (P=0.031) decreased. Overall symptoms improved in 58% on theophylline and 6% on placebo (P<0.02). There was no order effect.

CONCLUSIONS

Theophylline relaxed the esophageal wall, decreased hypersensitivity, and improved chest pain. Theophylline is effective in the treatment of functional chest pain.

The frontiers of reflux disease

Gastroesophageal reflux disease has frequently been implicated in a wide variety of complications beyond the esophagus. These so-called "extraesophageal" disorders range from diseases of the respiratory tract, such as asthma and bronchitis, to more remote sites and conditions such as otitis and dental erosion. Many articles proposing a link between reflux disease and a multitude of extraesophageal complications have been published, but indisputable evidence that these conditions are caused by reflux disease is rare. Much of the support for a link between reflux disease and a number of extraesophageal complications is based on the observation that reflux disease frequently coexists with other disorders. A causal link is difficult to prove, however, and this review aims to critically evaluate the available evidence, looking, where possible, at longitudinal studies, expert diagnoses, and response to acid-suppressive therapy as a means of determining the true relationship between GERD and its putative extraesophageal complications.

Gastroesophageal reflux disease in children with asthma: treatment implications

An association between asthma and gastroesophageal reflux disease (GERD) has long been recognized both mechanistically and epidemiologically. The clinical relevance of this interplay continues to be explored, with special interest given to the role of GERD in the worsening of asthma. The effect of GERD is most frequently contemplated in patients with asthma that is difficult to control. Medical and surgical anti-reflux trials attempting to alter asthma symptoms have reported mixed but generally underwhelming results, although asthma symptom scores are generally improved following effective treatment of GERD. Many of the pharmaceutical studies can be criticised for having too short a duration or for likely incomplete acid suppression. Few trials have specifically studied pediatric populations. Because GERD is a common condition, particularly in young children, the role reflux plays in the worsening of asthma symptoms and the potential benefit on asthma of anti-reflux therapy warrants further exploration. Whether or not treating symptomatic GERD reduces the symptoms and severity of asthma in children, GERD coexisting with asthma should be aggressively treated. GERD symptoms in most patients with or without asthma can be controlled medically with continuous use of proton pump inhibitors such as omeprazole and lansoprazole and to a lesser extent by histamine H(2) receptor antagonists such as famotidine and cimetidine.

Gastroesophageal reflux: a potential asthma trigger

Gastroesophageal reflux (GER) is a potential trigger of asthma. Approximately 77% of asthmatics report heartburn. GER is a risk factor for asthma-related hospitalization and oral steroid burst use. Asthmatics may be predisposed to GER development because of a high prevalence of hiatal hernia and autonomic dysregulation and an increased pressure gradient between the abdominal cavity and the thorax, over-riding the lower esophageal sphincter pressure barrier. Asthma medications may potentiate GER. Potential mechanisms of esophageal acid-induced bronchoconstriction include a vagally mediated reflex, local axonal reflexes, heightened bronchial reactivity, and microaspiration, all resulting in neurogenic inflammation. Anti-reflux therapy improves asthma symptoms in approximately 70% of asthmatics with GER. A 3-month empiric trial of twice-daily proton pump inhibitor given 30 to 60 minutes before breakfast and dinner can identify asthmatics who have GER as a trigger of their asthma.

Clinical presentation, diagnosis, and management of gastroesophageal reflux disease

GERD is ubiquitous throughout the adult population in the United States. It commonly adversely affects quality of life and occasionally causes life-threatening complications. The new and emerging medical and endoscopic therapies for GERD and the new management strategies for BE should dramatically reduce the clinical toll of this disease on society.

Extraesophageal manifestations of GERD

The association between gastroesophageal reflux disease (GERD) and extraesophageal disease is often referred to as extraesophageal reflux (EER). This article reviews EER, discussing epidemiology, pathogenesis, diagnosis, and treatment with a focus on the most studied and convincing EER disorders-asthma, cough, and laryngitis. Although EER comprises a heterogeneous group of disorders, some general characterizations can be made, as follows. First, although GERD's association with extraesophageal diseases is well-established, definitive evidence of causation has been more elusive, rendering epidemiological data scarce. Secondly, regarding the pathogenesis of EER, 2 basic models have been proposed: direct injury to extraesophageal tissue by acid and pepsin exposure or injury mediated through an esophageal reflex mechanism. Third, because heartburn and regurgitation are often absent in patients with EER, GERD may not be suspected. Even when GERD is suspected, the diagnosis may be difficult to confirm. Although endoscopy and barium esophagram remain important tools for detecting esophageal complications, they may fail to establish the presence of GERD. Even when GERD is diagnosed by endoscopy or barium esophagram, causation between GERD and extraesophageal symptoms cannot be determined. Esophageal pH is the most sensitive tool for detecting GERD, and it plays an important role in EER. However, even pH testing cannot establish GERD's causative relationship to extraesophageal symptoms. In this regard, effective treatment of GERD resulting in significant improvement or remission of the extraesophageal symptoms provides the best evidence for GERD's pathogenic role. Finally, EER generally requires more prolonged and aggressive antisecretory therapy than typical GERD requires.

Overuse of acid suppressive therapy in hospitalised patients with pulmonary diseases

OBJECTIVES

Overuse of acid suppressive therapy (AST) has been reported in hospitalised patients, but the use in specific patient categories is unexplored. We assessed the use of and indication for AST and upper endoscopic investigations in hospitalised patients on a pulmonary ward compared with patients on other wards.

METHODS

301 patients were enrolled in the study. 162 were hospitalised on a pulmonary ward with a control group consisting of 139 from both a surgical and general internal medicine ward. Adequate indications for AST were those strongly supported by medical literature.

RESULTS

Among the 301 patients enrolled, 132 (44%) used AST. 78 (59%) had no adequate indication for AST. On the pulmonary ward 79 (49%) patients used AST, compared to only 10 (20%) on the internal medicine ward (P < 0.05). On the pulmonary ward 68% of the patients had no adequate indication for AST, which was more common than inappropriate use of ASTon the control wards (P < 0.05). The most common inadequate indication for AST was peptic ulcer prophylaxis during corticoidsteroid therapy.

CONCLUSION

In hospitalised patients a significant overuse of AST was observed, particularly among pulmonary patients. More adequate use of AST can contribute to substantial savings for the health-care system.

Oral corticosteroids increase esophageal acid contact times in patients with stable asthma

STUDY OBJECTIVES

The prevalence of gastroesophageal reflux disease (GERD) is higher in people with asthma than in control populations. Predisposing factors for GERD development may include asthma medications such as prednisone. The objective of this study was to determine whether prednisone alters GERD parameters in people with asthma.

DESIGN

Prospective, single-blinded, placebo-controlled, crossover study.

SETTING

University medical center clinic.

PARTICIPANTS

Twenty adults with stable, moderate persistent asthma with minimal esophageal reflux symptoms (less than three times a week) who were not receiving antireflux therapy.

INTERVENTION

Prednisone, 60 mg/d, for 7 days.

MEASUREMENTS AND RESULTS

Asthma, esophageal reflux symptoms, and spirometry were measured during baseline, placebo, and prednisone phases, each 7 days in duration. Dual-probe esophageal pH monitoring, esophageal and respiratory manometrics (20 subjects), and basal and stimulated gastric acid secretion (4 subjects) were measured after placebo and prednisone phases. There were significant increases in esophageal acid contact times at the distal and proximal pH probes during the prednisone phase. Total percentage of time that pH was < 4.0 at the distal probe was 2.5 +/- 0.4% for placebo compared with 5.9 +/- 0.9% for prednisone (p < 0.002). Total percentage of time that pH was < 4.0 at the proximal probe was 0.3 +/- 0.1% for placebo and 0.8 +/- 0.2% for prednisone (p < 0.0007). There were no significant changes in subject weight, spirometry, asthma or esophageal reflux symptoms, manometrics, or basal or stimulated gastric acid secretion.

CONCLUSION

Prednisone, 60 mg/d for 7 days, increased esophageal acid contact times in this small population of people with stable asthma; however, the mechanism for this finding is unclear.

Gastroesophageal reflux, asthma, and mechanisms of interaction

Gastroesophageal reflux (GER) is a potential trigger of asthma. The esophagus and lung interact through a variety of mechanisms. Esophageal acid-induced bronchoconstriction can be provoked by a vagally mediated reflex, whereby acid in the distal esophagus produces airway responses; by neural enhancement of bronchial reactivity, whereby esophageal acid augments airway hyperresponsiveness; or by microaspiration, in which small amounts of esophageal acid in the upper airway cause significant airway responses. Interestingly, even in the microaspiration model, the vagus nerve plays a significant role. Neurogenic inflammation in the lung may occur with either vagally mediated mechanisms or with microaspiration. The prevalence of reflux symptoms, esophagitis, and abnormal esophageal acid contact time is higher in patients with asthma than in control populations. Potential mechanisms, whereby asthma may predispose to the development of GER, include autonomic dysregulation, an increased pressure gradient differential between the thorax and the abdomen, a high prevalence of hiatal hernia, alterations in crural diaphragm function, and bronchodilator medication use. Further research will help define how the esophagus and lung interact.

Prevalence, pathophysiology, and treatment of patients with asthma and gastroesophageal reflux disease

About one third of the US adult population experiences symptoms of gastroesophageal reflux on a monthly basis. Asthma is present in about 5% of the same population. This article reviews and summarizes the literature in the following areas: (1) prevalence of gastroesophageal reflux disease (GERD) in asthmatic patients based on clinical symptoms, endoscopic esophagitis, and 24-hour ambulatory esophageal pH recordings; (2) proposed pathophysiologic mechanisms linking the 2 diseases; and (3) medical and surgical treatment trial results of antireflux therapy for asthmatic patients. Asthmatic patients appear to have an increased prevalence of GERD symptoms and 24-hour esophageal acid exposure. The clinical management of these patients remains controversial. Common management approaches to GERD in asthmatic patients include medical therapy with a proton pump inhibitor and/or antireflux surgery, which improve asthma symptoms in many patients but minimally affect pulmonary function.

Gastroesophageal reflux and asthma: are they related?

The relationship between asthma and gastroesophageal reflux (GER) is controversial. This paper reviews the evidence for an association between them, the effect of asthma on GER, and the effects of GER and antireflux therapy on asthma. The association between the two conditions seems firm but studies of the effects of GER on asthma and asthma on GER are contradictory. Critical review suggests that GER affects asthma symptoms but not pulmonary function. Antireflux therapy improves asthma symptoms and reduces medication requirements but does not improve pulmonary function. The paradox of GER causing asthma symptoms but not changing pulmonary function may be explained by its increasing minute ventilation rather than triggering bronchospasm.

Gastric asthma: an unrecognized disease with an unsuspected frequency

Bronchial asthma is a disease that has been recognized for centuries, which is influenced mainly by genetic and environmental factors. The current interest of bronchial asthma is focused to ascertain the causes and the mechanisms that induce bronchoconstriction. Recently, abnormalities of the esophageal and gastric tracts have become important related areas for research. In predisposed individuals, these abnormalities can trigger or worsen the particular syndrome better known as "gastric asthma." In bronchial asthma the disorder of gastroesophageal reflux (GER) occurs more often than would be expected by chance. The neurogenic mechanism is considered to be the main cause of bronchoconstriction. The diagnosis of gastric asthma is particularly difficult and it should be considered also when GER is less evident or not recognized. In asthmatic patients the recognition of gastric abnormalities is very relevant for therapeutic problems also when GER is in a subclinical stage. In fact, many drugs used in the treatment of bronchial asthma can promote or enhance GER and subsequently they can worsen the symptoms of gastric asthma.

24-h esophageal pH testing in asthmatics: respiratory symptom correlation with esophageal acid events

BACKGROUND

Gastroesophageal reflux (GER) may be a trigger for asthma and may be clinically silent. Twenty-four-hour esophageal pH testing accurately diagnoses GER in asthmatics. There are no reports correlating respiratory symptoms with esophageal acid events. This study examines the prevalence and severity of GER in asthmatics with and without reflux symptoms and examines respiratory symptom correlation with esophageal acid.

METHODS

All esophageal manometry and 24-h esophageal pH tests performed were reviewed in asthmatics who met entrance criteria from July 1, 1989, through November 1, 1994. GER was present if esophageal pH tests were abnormal. Results of esophageal tests were compared for asthmatics with reflux symptoms and GER and asthmatics without reflux symptoms and GER. Respiratory symptoms correlated with esophageal acid events if the esophageal pH was < 4 simultaneously with the respiratory event or within 5 min before its onset.

RESULTS

Of 199 asthmatics who qualified for analysis, 164 (82%) had reflux symptoms. The results of 24-h esophageal pH tests were abnormal in 118 of 164 asthmatics with reflux symptoms (72%), compared with 10 of 35 asthmatics without reflux symptoms (29%). Among asthmatics with GER, 119 of 151 respiratory symptoms (78.8%) were associated with esophageal acid. Seventy-six of 84 reported coughs (90.5%) were associated with esophageal acid. Theophylline did not alter esophageal parameters.

CONCLUSIONS

There is a strong correlation between esophageal acid events and respiratory symptoms in asthmatics with GER. Respiratory symptom correlation with esophageal acid events further supports that GER may be a trigger for asthma.

Respiratory complications of gastrointestinal diseases

Further advances in the ability to diagnose GER disease by use of ambulatory pH monitoring have unveiled a host of extraesophageal manifestations of GERD. These include pulmonary symptoms of asthma, recurrent pneumonia, cough or bronchitis, and infant apnea. Many of these symptoms may be the sole presentations of GER in these patients. It is important that the clinician is aware of these atypical presentations of GERD. The expanding use of ambulatory pH monitoring is helping to clarify the underlying pathophysiology of these disorders as well as to improve the ability to diagnose the atypical manifestations of GERD.

[Bronchopulmonary manifestations of gastroenterologic and hepatic diseases]

Topics of this review are the bronchopulmonary manifestations of gastroesophageal reflux disease, cirrhosis of the liver and chronic inflammatory bowel diseases. About 20% of patients with chronic obstructive airway disease show evidence of gastroesophageal reflux disease. Reflux bronchoconstriction seems to be of greater importance than microaspiration. First studies show the positive effects of acid inhibition by proton pump inhibitors on pulmonary symptoms. Hepatorenal syndrome is characterized by arterial hypoxemia with PaO2-values < 70 mm Hg. Different mediators (endotoxins, amines, polypeptides or allergens) are discussed. Furthermore, elevated levels of prostacycline, atrial natriuretic factor and platelet activating factor have been described. Recently published studies focused on the role of nitric oxide (NO). Patients with cirrhosis of the liver show a higher rate of a pathologically elevated airway resistance which might be induced by a reduced histamine clearance. Ascites leads to reversible restrictive airway disease. Bronchopulmonary manifestations in chronic inflammatory bowel diseases include obstructive and restrictive airway diseases, vascular or serosal changes and show low clinical evidence. In contrast, pathological changes of the common function tests were found in 30 to 50%. These findings may be induced by circulating immune complexes, vasculitis, increased permeability or a combined immune reaction of both, the bronchial and intestinal mucosa. Undesired effects of salicylates should be taken into account. This review shows that bronchopulmonary manifestations in diseases of the Gl-tract or the liver are more common than usually known and should be taken into clinical consideration.

Medical therapy of gastroesophageal reflux and management of esophageal strictures

The goals of modern medical therapy for gastroesophageal reflux disease are threefold: first, eliminate symptoms; second, heal injured esophageal mucosa; third, manage and/or prevent complications. Selection of a particular medical regimen depends on the severity of the disease, effectiveness of the therapy, cost, and convenience of the medical regimen. An accurate diagnosis needs to be made in patients suspected with esophageal strictures. If there is a treatable underlying disease, specific therapy is essential. The goal of dilation therapy should be established and set about to accomplish in a timely, but unhurried fashion. Fluoroscopy and wire-guided dilators should be used liberally, especially for difficult strictures.

Gastro-oesophageal reflux disease and asthma

Gastro-oesophageal reflux disease (GOR) and asthma are both common medical conditions that often co-exist. Studies using oesophageal manometry and 24 h ambulatory pH monitoring have shown that up to 80% of asthmatics have abnormal GOR. A number of mechanisms whereby GOR may trigger asthma have been proposed, and it is believed that acid reflux may stimulate vagal receptors in the lower oesophagus causing reflex bronchoconstriction. However, GOR may be worsened by asthma causing abnormal diaphragm mechanics and by its treatment. Formal evaluation of GOR should be considered a part of asthma assessment, particularly if asthmatic symptoms are precipitated by factors known to trigger GOR such as reclining, alcohol ingestion, and the use of theophylline. Twenty-four hour ambulatory intra-oesophageal pH monitoring remains the gold standard for the diagnosis of GOR. Medical therapy with anti-reflux medications, such as acid suppressive agents and prokinetic agents may improve both GOR and asthma control. In those who fail medical therapy, anti-reflux surgery may be warranted in some.

Respiratory complications of gastroesophageal reflux disease

There is a relationship between gastroesophageal reflux disease and certain respiratory symptoms and findings. Among these are cough, laryngitis, and wheezing dyspnea. The pathophysiology of these conditions can vary from actual aspiration of gastric content to esophageal mucosal inflammation with the respiratory symptoms induced by a vagally mediated reflex mechanism.

Gastro-oesophageal reflux and severity of pulmonary disease in cystic fibrosis

The correlation between oesophageal dysfunction (OD), pathologic gastro-oesophageal reflux (GOR), and severity of pulmonary disease was studied in 12 patients with cystic fibrosis (CF). They were interviewed about symptoms of OD and underwent 24-h pH recording in the oesophagus, oesophageal manometry combined with reflux provocation tests, the acid perfusion test, the acid clearance test, lung function tests, and scoring of the chest radiograph. Six of the 12 patients reported symptoms of OD. Abnormal GOR, as shown by 24-h pH monitoring of the oesophagus, was found in eight of them. Altogether 9 of the 12 participants had at least one pathologic oesophagus test result. Results of radiologic examinations of the oesophagus, performed in six patients, were pathologic. The four patients with the best chest radiograph scores and the best lung function had significantly less signs and symptoms of OD and GOR than the other eight patients. We conclude that OD, GOR, and pulmonary disease covariate in CF.

The otolaryngologic manifestations of gastroesophageal reflux disease (GERD): a clinical investigation of 225 patients using ambulatory 24-hour pH monitoring and an experimental investigation of the role of acid and pepsin in the development of laryngeal injury

Occult (silent) gastroesophageal reflux disease (GER, GERD) is believed to be an important etiologic factor in the development of many inflammatory and neoplastic disorders of the upper aerodigestive tract. In order ot test this hypothesis, a human study and an animal study were performed. The human study consisted primarily of applying a new diagnostic technique (double-probe pH monitoring) to a population of otolaryngology patients with GERD to determine the incidence of overt and occult GERD. The animal study consisted of experiments to evaluate the potential damaging effects of intermittent GER on the larynx. Two hundred twenty-five consecutive patients with otolaryngologic disorders having suspected GERD evaluated from 1985 through 1988 are reported. Ambulatory 24-hour intraesophageal pH monitoring was performed in 197; of those, 81% underwent double-probe pH monitoring, with the second pH probe being placed in the hypopharynx at the laryngeal inlet. Seventy percent of the patients also underwent barium esophagography with videofluoroscopy. The patient population was divided into seven diagnostic subgroups: carcinoma of the larynx (n = 31), laryngeal and tracheal stenosis (n = 33), reflux laryngitis (n = 61), globus pharyngeus (n = 27), dysphagia (n = 25), chronic cough (n = 30), and a group with miscellaneous disorders (n = 18). The most common symptoms were hoarseness (71%), cough (51%), globus (47%), and throat clearing (42%). Only 43% of the patients had gastrointestinal symptoms (heartburn or acid regurgitation). Thus, by traditional symptomatology, GER was occult or silent in the majority of the study population. Twenty-eight patients (12%) refused or could not tolerate pH monitoring. Of the patients undergoing diagnostic pH monitoring, 62% had abnormal esophageal pH studies, and 30% demonstrated reflux into the pharynx. The results of diagnostic pH monitoring for each of the subgroups were as follows (percentage with abnormal studies): carcinoma (71%), stenosis (78%), reflux laryngitis (60%), globus (58%), dysphagia (45%), chronic cough (52%), and miscellaneous (13%). The highest yield of abnormal pharyngeal reflux was in the carcinoma group and the stenosis group (58% and 56%, respectively). By comparison, the diagnostic barium esophagogram with videofluoroscopy was frequently negative. The results were as follows: esophagitis (18%), reflux (9%), esophageal dysmotility (12%), and stricture (3%). All of the study patients were treated with antireflux therapy. Follow-up was available on 68% of the patients and the mean follow-up period was 11.6 +/- 12.7 months.(ABSTRACT TRUNCATED AT 400 WORDS)

Nocturnal oxygen saturation and body movement in asthmatics treated with controlled-release preparations of theophylline or terbutaline

Nine adult asthmatics with a history of nocturnal symptoms and with morning dips in peak expiratory flow (PEF) were treated for 10-14 days with 24-h controlled-release preparation of theophylline (Th), or a controlled-release preparation of terbutaline (Te), in a double-blind cross-over experiment. During treatment with 450-900 mg Th in the evening morning, plasma drug levels ranged from 53-95 (mean 73) mumol/l. The Te dose was 7.5 mg twice daily. Morning PEF values during Th (mean 338 l.min-1) and Te (316 l.min-1) were not significantly different. There were no significant differences between the treatments in average nocturnal oximetric O2 saturation (91.9% during Th and 91.0% during Te), or the amount of nocturnal body movement, recorded with a static charge sensitive bed (total number of movements 146 during Th and 120 during Te). No difference between the treatments was seen with respect to assessment by the subjects of sleep quality, which was considered fair or good. The findings suggest that in moderately severe asthma, nocturnal oxygenation and sleep quality were similar during the two treatments.