Quantitative gastroesophageal reflux and pulmonary function in asthmatic children and normal adults receiving placebo, theophylline, and metaproterenol sulfate therapy

Clinical features of asthma in children differ with regard to the intensity of distal gastroesophageal acid reflux

BACKGROUND

The prevalence of gastroesophageal reflux (GER) in children with asthma is higher than in healthy controls, but the nature and direction of this association is unclear.

OBJECTIVE

The aim of our study was to assess the relationship between esophageal acid exposure and the clinical features of asthma in children.

METHODS

In total, 66 children (mean age 122.8 months [SD 44.89 months]) with chronic pulmonary symptoms, fulfilling diagnostic criteria of persistent asthma, underwent 24-hour esophageal pH monitoring and answered a detailed questionnaire-based survey. The questionnaire topics included environmental factors, familial history, current and previous clinical symptoms, atopy, asthma severity, and medication.

RESULTS

Abnormal results of 24-hour esophageal pH monitoring were found in 28 out of 66 children (42.4%). Age, sex, severity of asthma, environmental factors, spirometry results, and the type of medication did not correlate with esophageal acid exposure. However, children with abnormal pH results developed asthma significantly earlier (asthma onset 3.63 years [SD 2.52 years] vs 5.77 years [SD 3.82 years]; p < .01). Nonatopic individuals had more intensive esophageal acid exposure than atopic ones (Boix-Ochoa score 28.19 [SD 18.26] vs 18.26 [SD 12.84]; p < .048). The intensity of GER was also significantly correlated with frequent or difficult-to-control nighttime asthma attacks.

CONCLUSIONS

There are differences in clinical features of asthma in children with regard to the intensity of esophageal acid exposure. Symptoms of asthma in nonatopic individuals with early onset and difficult-to-control nighttime asthma attacks suggest the possibility of concomitant, clinically relevant GER.

Oral xanthines as maintenance treatment for asthma in children

BACKGROUND

Xanthines have been used in the treatment of asthma as a bronchodilator, though they may also have anti-inflammatory effects. The current role of xanthines in the long-term treatment of childhood asthma needs to be reassessed.

OBJECTIVES

To determine the efficacy of xanthines (e.g. theophylline) in the maintenance treatment of paediatric asthma.

SEARCH STRATEGY

A search of the Cochrane Airways Group Specialised Register was undertaken with predefined search terms. Searches are current to May 2005.

SELECTION CRITERIA

Randomised controlled trials,lasting at least four weeks comparing a xanthine with placebo, regular short-acting beta-agonist (SABA), inhaled corticosteroids (ICS), cromoglycate (SCG), ketotifen (KET) or leukotriene antagonist, in children with diagnosed with chronic asthma between 18 months and 18 years old.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected each study for inclusion in the review and extracted data. Primary outcome was percentage of symptom-free days.

MAIN RESULTS

Thirty-four studies (2734 participants) of adequate quality were included. Xanthine versus placebo (17 studies): The proportion of symptom free days was larger with xanthine compared with placebo (7.97% [95% CI 3.41, 12.53]). Rescue medication usage was lower with xanthine, with no significant difference in symptom scores or hospitalisations. FEV1 , and PEF were better with xanthine. Xanthine was associated with non - specific side-effects. Data from behavioural scores were inconclusive. Xanthine versus ICS (four studies) : Exacerbations were less frequent with ICS, but no significant difference on lung function was observed. Individual studies reported significant improvements in symptom measures in favour of steroids, and one study reported a difference in growth rate in favour of xanthine. No difference was observed for study withdrawal or tremor. Xanthine was associated with more frequent headache and nausea. Xanthine versus regular SABA (10 studies): No significant difference in symptoms, rescue medication usage and spirometry. Individual studies reported improvement in PEF with beta-agonist. Beta-agonist treatment led to fewer hospitalisations and headaches. Xanthine was associated with less tremor. Xanthine versus SCG (six studies ): No significant difference in symptoms, exacerbations and rescue medication. Sodium cromoglycate was associated with fewer gastro-intestinal side-effects than xanthine. Xanthine versus KET (one study): No statistical tests of significance between xanthine and ketotifen were reported. Xanthine + ICS versus placebo + same dose ICS (three studies) : Results were conflicting due to clinical/methodological differences, and could not be aggregated.

AUTHORS' CONCLUSIONS

Xanthines as first-line preventer alleviate symptoms and reduce requirement for rescue medication in children with mild to moderate asthma. When compared with ICS they were less effective in preventing exacerbations. Xanthines had similar efficacy as single preventative agent compared with regular SABA and SCG. Evidence on AEs (adverse effects) was equivocal: there was evidence for increased AEs overall, but no evidence that any specific AE (including effects on behaviour and attention) occurred more frequently than with placebo. There is insufficient evidence from available studies to make firm conclusions about the effectiveness of xanthines as add-on preventative treatment to ICS, and there are no published paediatric studies comparing xanthines with alternatives in this role. Our data suggest that xanthines are only suitable as first-line preventative asthma therapy in children when ICS are not available. They may have a role as add-on therapy in more severe asthma not controlled by ICS, but further studies are needed to examine this, and to define the risk-benefit ratio compared with other agents.

The spectrum of pulmonary symptoms due to gastroesophageal reflux

Most asthmatics have GER, and the evidence is strong that GER plays an important role in some patients who have asthma. Despite sophisticated study methods and technologically advanced diagnostic tests, the results of published studies on mechanisms have failed to provide a diagnostic test with a degree of certainty great enough to identify which patients have GER-induced or GER-exacerbated asthma and which patients will respond to antireflux therapy. The difficulties involved in establishing a definite cause-and-effect relationship between GER and asthma are real. Even positive results on such direct tests as sputum inspection and scintigraphic monitoring, both of which establish reflux into the tracheobronchial tree, do not necessarily establish cause or effect and cannot be used to predict outcomes. Ambulatory esophageal pH testing can suggest, but cannot prove, the diagnosis of GER-induced asthma, and pH testing cannot be relied on safely to make clinical decisions. A trial of a proton pump inhibitor (PPI) is indicated to assess if asthma improves subjectively and objectively, but the dose must be high enough to prevent even silent esophageal acid exposure, and the duration must be long enough to allow for detection of even subtle trends in subjective and objective respiratory improvement. Antireflux surgery remains a therapeutic option and should not be withheld if GER is a reasonable suspect in asthma exacerbations. Although strong opinions have been voiced as to whether or not a good response to PPI therapy predicts a good response to antireflux surgery, the opinions, although logical, are based on personal experience and gut feelings; a good PPI response may not necessarily predict a good surgery response. Opinions suggesting that a poor response to PPI predicts a poor response to antireflux surgery also may seem logical but are not based on clinical data; a poor PPI response may not necessarily predict a poor antireflux surgery response. When the method is found that predicts which patients who have GER and asthma will respond to antireflux treatment, the results could be profound: fewer hospitalizations for respiratory complications, less pulmonary morbidity and mortality, less need for pulmonary medications, less time lost from work, fewer visits to physicians' offices, and less illness associated with corticosteroid therapy. For the present, however, clinical judgment and good sense still are our best friends. It is not unreasonable to urge patients to alter their lifestyle: the huge volume, calorie-dense, high-fat meals eaten before bedtime are not likely to prevent GER or add to their life expectancy.

Clinical implications of gastroesophageal reflux disease and swallowing dysfunction in COPD

The intimate anatomical and physiologic relationship between the upper airway and esophagus consists of complex interactions between various muscles and nerves with both voluntary and involuntary patterns of control. Alterations in this harmonic relationship can lead to swallowing abnormalities ranging from dysphagia to gross aspiration, gastroesophageal reflux disease (GERD) and chronic cough. There is a paucity of data regarding pathologic alterations in the upper airway-esophageal relationship in patients with COPD. The association between GERD and respiratory symptoms is well recognized in the setting of asthma; however, the nature of this relationship remains controversial. The association of GERD and COPD is even less clear. A review of the limited data on GERD and swallowing abnormalities in patients with COPD indicate that prevalence of GERD and esophageal disorders in patients with COPD is higher than in the normal population. However, its contribution to respiratory symptoms, bronchodilator use and pulmonary function in patients with COPD remains unknown. Although dysphagia and swallowing dysfunction on videofluoroscopic swallow evaluation are common in patients with COPD, their role as exacerbators of COPD remains to be elucidated. Further clinical research is necessary to evaluate the role of GERD and swallowing dysfunction in both stable and acute exacerbation of COPD.

Helicobacter pylori infection and reflux esophagitis in children with chronic asthma

BACKGROUND

Reflux esophagitis is uncommon in countries in which most people are colonized by H. pylori infection and is extremely rare in persons with reflux esophagitis, although esophagitis is detected in almost 50% of children with recurrent lower respiratory tract symptoms.

HYPOTHESIS

Failure to acquire H. pylori can enhance esophagitis risk in children with chronic asthma.

PATIENTS AND METHODS

Forty-two pediatric out-patients with chronic asthma (mean age 13.2 +/- 1.18 years, range 12-15 years, 23 boys and 19 girls) were included in the study. They had undergone endoscopy with gastric and esophageal biopsies for upper dyspeptic complaints. H. pylori positivity was confirmed by positive Giemsa staining. Esophagitis was diagnosed by standard histologic procedure (presence of intraepithelial leukocytes or basal cell hyperplasia).

RESULTS

H. pylori colonization was detected histologically in 22 of 42 patients (52.4%) enrolled in the study. Histology demonstrated that in asthmatic children with evidence of H. pylori infection esophagitis was a dramatically rare finding than in the patients without the infection (P < 0.001). It was an unexpected finding, that lung function parameters (FEF50, FEF75) were significantly lower in asthmatics infected with H. pylori (P < 0.05).

CONCLUSION

The present findings suggest inverse association between esophagitis and H. pylori in course of asthma in pediatric patients.

Supra-oesophageal manifestations of gastro-oesophageal reflux disease

Since the early 1960s, many studies have been published that consider the possible relationship between gastro-oesophageal (acid) reflux (GORD) and various other complaints, including dental erosions, ear, nose and throat problems, chronic cough and asthma. Although a high coincidence of GORD and these supra-oesophageal complaints have been noted, there is no consensus on the pathophysiology and management of such complications. In this article we review the literature published between 1966 and 2000 on this subject. We also analyse the available information on the incidence, pathophysiological mechanisms, diagnostic approach and therapeutic options in the various subgroups of disorders.

Gastroesophageal reflux in asthmatic children not responding to asthma medication: a scintigraphic study in 126 patients with correlation between scintigraphic and clinical findings of reflux

Gastroesophageal reflux (GER) is frequently found in association with asthma. Successful control of GER in these patients may improve in their asthma symptoms. The present retrospective analysis was undertaken to find out the incidence of GER in asthmatic children not responding to routine antiasthmatic medications and to find out if there is a clinical correlation between the symptoms of GER and scintigraphic evidence of GER in these patients. A total of 126 children with a mean age of 2.31 years and range 6 months to 6 years were evaluated. The children were divided into two groups. Group I (n = 100) consisted of children with asthma but no clinical symptoms of GER. Group II (n = 26) consisted of those children with asthma and clinical symptoms of GER. Radionuclide scintigraphy was performed with 100-200 microCi (3.7-7.4 MBq) of Tc99m-sulphur colloid. All 33 out of 126 (26%) children had GER on scintigraphy. In Group I, only 23 (23%) had reflux while in Group II, 10 (38.5%) had reflux. In conclusion, esophageal scintiscanning can be used to detect GER in asthmatic children refractory to routine antiasthmatic medication irrespective of the presence or absence of symptoms suggestive of GER.

Increased prevalence of gastroesophageal reflux symptoms in patients with COPD

STUDY OBJECTIVES

To determine the prevalence of gastroesophageal reflux (GER) symptoms in patients with COPD and the association of GER symptoms with the severity of airways obstruction as assessed by pulmonary function tests (PFTs).

DESIGN

Prospective questionnaire-based, cross-sectional analytic survey.

SETTING

Outpatient pulmonary and general medicine clinics at a Veterans Administration hospital.

PATIENTS

Patients with mild-to-severe COPD (n = 100) were defined based on American Thoracic Society criteria. The control group (n = 51) consisted of patients in the general medicine clinic without respiratory complaints or prior diagnosis of asthma or COPD.

INTERVENTION

Both groups completed a modified version of the Mayo Clinic GER questionnaire.

RESULTS

Compared to control subjects, a greater proportion of COPD patients had significant GER symptoms defined as heartburn and/or regurgitation once or more per week (19% vs 0%, respectively; p < 0.001), chronic cough (32% vs 16%; p = 0.03), and dysphagia (17% vs 4%; p = 0.02). Among patients with COPD and significant GER symptoms, 26% reported respiratory symptoms associated with reflux events, whereas control subjects denied an association. Significant GER symptoms were more prevalent in COPD patients with FEV(1) < or %, as compared with patients with FEV(1) > 50% of predicted (23% vs 9%, respectively; p = 0.08). In contrast, PFT results were similar among COPD patients with and without GER symptoms. An increased number of patients with COPD utilized antireflux medications, compared to control subjects (50% vs 27%, respectively; p = 0.008).

CONCLUSIONS

The questionnaire demonstrated a higher prevalence of weekly GER symptoms in patients with COPD, as compared to control subjects. There was a trend toward higher prevalence of GER symptoms in patients with severe COPD; however, this difference did not reach statistical significance. We speculate that although GER may not worsen pulmonary function, greater expiratory airflow limitation may worsen GER symptoms in patients with COPD.

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.

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.

Gastroesophageal reflux and asthma

The medical literature has been deluged with articles on the relation between gastroesophageal reflux (GER) and asthma. In an effort to piece together the complex puzzle, investigators from all disciplines have gathered their patients with wheezing and heartburn and studied the epidemiology, the possible cause or effect mechanisms and the therapeutic response to GER treatment. Indeed, since humans first began to hunker down and work together to discuss interesting observations, the world has begun to breathe easier. Epidemiological evidence for a GER/asthma association suggests that about three-fourths of asthmatics, independent of the use of bronchodilators, have acid GER, increased frequency of reflux episodes, or heartburn; and 40% have reflux esophagitis. Physiological studies suggest that 2 separate mechanisms are involved in the GER/asthma relationship: (1) a vagally mediated pathway and (2) microaspiration. In any given patient, however, there is no acceptable diagnostic method available to confirm the presence or absence of GER-induced asthma. Clinical trials, using antireflux medical therapy and antireflux surgery have begun to provide some clues about GER-related pulmonary symptoms. The trials of medical therapy using acid suppressing drugs (e.g. histamine-2 receptor antagonists) have ranged from no benefit to modest improvement of only nocturnal asthma symptoms. Studies with proton-pump inhibitors are underway. In uncontrolled surgical studies, antireflux surgery has resulted in partial or complete remission of asthma symptoms in a large proportion of patients. Despite the uncontrolled nature of these studies, many patients have had dramatic subjective improvement in pulmonary symptoms. It appears for now that clinical trials are the only available means to assess whether medical or surgical treatment of GER in patients with both GER and asthma improves the symptoms of asthma and decreases the need for pulmonary medications. One conclusion is certain: We no longer can ignore the important co-existent nature of these 2 afflictions.

The area under pH curve: a single-figure parameter representative of esophageal acid exposure

This investigation aims at providing simpler methods for reading esophageal extended pH-metering tracings. Because the currently used parameters only quantify frequency and duration of acid exposure, we have measured the area between the pH curve and the pH 4 line (area under curve [AUC]) in an attempt to include in the evaluation the severity of acid exposure as well. We compared 20 control and 63 children with gastroesophageal reflux (GER). Extended pH metering curves were read according to currently accepted methods. In addition, we measured planimetrically total 24-hour AUC, AUC during daytime, AUC during sleep time, and total AUC excluding 2-hour postprandial periods. In spite of the very significant differences found between means of controls and GER patients for all variables considered, values overlapped widely. Receiver-operating characteristic (ROC) analysis indicated the best threshold values for differentiation of controls and GER patients and tested the diagnostic efficiency for each variable. We found that 24-hour AUC was the best comprehensive value (sensitivity = 1, specificity = 1) and that there was probably no use for fractional evaluation during selected periods of time. The optimum 24-hour AUC threshold value in the present conditions of measurement (paper speed, 0.25 cm/min; 1 pH unit, 2.5 cm) was 20 cm2. In order to facilitate comparison we propose using a pH-surface unit (pHSU) equal to recording speed (in cm/min) multiplied by vertical shift per 1 pH unit (in centimeters) (in this case, 0.25 x 2.5 = 0.625 cm2). A threshold value of 20 cm2 thus becomes 32 pHSU. A similar transformation will be adequate for any other recording conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastroesophageal reflux and respiratory symptoms: is there an association? Proposed mechanisms and treatment

Gastroesophageal reflux (GER) is a dysfunction of the distal esophagus causing movement of stomach contents into the esophagus. Patients may develop heartburn, regurgitation, dysphagia, odynophagia, and hemorrhage. Respiratory symptoms occur in 10-60 percent of patients with GER or hiatal hernia. Although there is evidence associating pulmonary symptoms and GER, causality has not been proven. The appropriate use of antireflux therapy or surgery to treat GER may consequently alleviate respiratory symptoms.

The actions of some beta-receptor agonists and xanthines on isolated muscle strips from the human oesophago-gastric junction

Isolated preparations from the circular muscle layer of the human oesophago-gastric junction were mounted in organ baths and isometric tension recorded. During an equilibration period, active resting tension developed suggesting that the preparations were representing the lower oesophageal sphincter. Active tension was abolished by exposing the preparations to Ca(++)-free medium. The two xanthines theophylline and enprofylline almost equipotently relaxed the preparations in a concentration-dependent manner (10(-7)-10(-3) M). Within therapeutic concentrations, theophylline inhibited active resting tension by 30-60%, while enprofylline lowered tension by less than 20%. Inhibitory actions of adenosine were demonstrated, and this suggests that adenosine antagonism is not the mechanism of action for xanthines in the oesophagus. Non-selective beta-receptor stimulation with isoprenaline inhibited active tension by 70% (10(-7) M), while beta 2-receptor stimulation with terbutaline inhibited tension by 47% (10(-5) M). Dobutamine, believed to preferentially stimulate beta 1-receptors, inhibited active tension in a concentration-dependent manner (10(-7)-10(-4) M). Metoprolol (10(-6) M), a selective beta 1-receptor antagonist, shifted the concentration-response curve for isoprenaline to the right, but left the maximal response unchanged. It is concluded that xanthines and beta-receptor agonists have inhibitory actions on circular muscle from the human oesophagogastric junction. The experimental data suggest the presence of beta 1- as well as beta 2-receptors, both mediating inhibition of active resting tension.

Most asthmatics have gastroesophageal reflux with or without bronchodilator therapy

The relationship between gastroesophageal reflux and asthma has not been clearly defined. We measured the lower esophageal sphincter pressures and studied gastroesophageal reflux patterns over 24 hours using an ambulatory Gastroreflux Recorder (Del Mar Avionics, Irvine, CA) in 44 controls and 104 consecutive adult asthmatics. The presence or absence of reflux symptoms was not used as a selection criterion for asthmatics. All asthmatics had discrete episodes of diffuse wheezing and documented reversible airway obstruction of at least 20%. Patients underwent reflux testing while receiving, if any, their usual asthmatic medications: 71.2% required chronic bronchodilators and 28.8% required no bronchodilators. Compared with controls, asthmatics had significantly decreased lower esophageal sphincter pressures, greater esophageal acid exposure times, more frequent reflux episodes, and longer clearance times in both the upright and supine positions (P less than 0.0001 for all parameters tested). There were no differences in any of the measured reflux parameters between asthmatics who required bronchodilators and those who did not. Thus, the decreased lower esophageal sphincter pressures and increased levels of acid reflux in asthmatics were not entirely caused by the effects of bronchodilator therapy. Receiver-operating characteristic analysis generated reflux values that discriminated asthmatics from controls. More than 80% of adult asthmatics have abnormal gastroesophageal reflux. We conclude that most adult asthmatics, regardless of the use of bronchodilator therapy, have abnormal gastroesophageal reflux manifested by increased reflux frequency, delayed acid clearance during the day and night, and diminished lower esophageal sphincter pressures.

Effect of positions, eating, and bronchodilators on gastroesophageal reflux in asthmatics

Gastroesophageal reflux is common in asthmatics. To determine whether bronchodilators, the supine position, or eating affect gastroesophageal reflux, we performed ambulatory 24-hr pH monitoring on 44 controls and 104 unselected adult asthmatics. All asthmatics had discrete attacks of wheezing and documented reversible airway obstruction of at least 20%. The presence or absence of gastroesophageal reflux symptoms was not used as a criterion for patient selection. Chronic bronchodilator therapy was required by 71.2% of the asthmatics, and was continued during the test. Asthmatics had significantly worse GER than controls during the 3-hr postprandial period, which continued into the nonpostprandial period up to the next meal. Significant differences were present for esophageal mucosal acid contact time, frequency of reflux episodes, and clearance times. During the nonpostprandial periods asthmatics had four times the acid reflux as controls and 19-fold the frequency of prolonged reflux episodes. There were no differences between asthmatics on bronchodilators and those not on bronchodilators in any of the reflux parameters during the upright (postprandial, nonpostprandial) period or supine (sleep) period (P = NS). We conclude that: (1) regardless of the use of bronchodilator therapy, asthmatics have significant GER when asleep and after meals that continues beyond the postprandial period to the next meal; and (2) asthmatics receiving bronchodilators have similar gastroesophageal reflux patterns after eating, in the nonpostprandial period, and when asleep as asthmatics not receiving bronchodilators.

Gastroesophageal reflux and asthma

Gastroesophageal reflux provokes asthma in many patients. Conversely, asthma predisposes to gastroesophageal reflux. In many patients, reflux therapy will ameliorate asthma. Recognition of this relationship is facilitated by physician awareness, clinical history, selected laboratory tests, and ultimately, a careful monitoring of the response to antireflux therapy. With the introduction of effective medical antireflux therapy, the opportunity to benefit these patients has increased. Surgical management of reflux-provoked asthma remains an effective and useful alternative in selected patients.

Gastroesophageal reflux and diseases of the respiratory tract: a review

Gastroesophageal reflux is an important cause of chronic respiratory disorders. In at least two common pulmonary conditions, chronic bronchitis and asthma, there may be a ying-yang association between the pulmonary disease and gastroesophageal reflux. Gastroesophageal-provoked disease needs to be evaluated in patients with chronic respiratory disease whose condition is progressing in spite of adequate medical therapy; whose history strongly supports this concept; and whose laboratory tests suggest a causal relationship. Recognition and treatment of gastroesophageal reflux, either medical or surgical, can benefit respiratory problems of many patients.

Ambulatory pH monitoring of gastro-oesophageal reflux in "morning dipper" asthmatics

A causal relation between gastro-oesophageal reflux and nocturnal asthma has been postulated. Forty four adult asthmatics underwent ambulatory monitoring of their oesophageal pH over 24 hours to find out if there was such a relation. Of these 21 showed significant "morning dipping" in which the peak expiratory flow falls during the night. Asthmatics with morning dipping had a history of nocturnal wheeze and a higher incidence of reflux symptoms, but measurement of oesophageal pH showed no significant difference in the amount or pattern of reflux when compared with "non-dippers." Overall, 15 asthmatics had gastro-oesophageal reflux, and these participated in a randomised, double blind crossover trial of ranitidine versus placebo. No significant difference was found in the peak expiratory flow rates or subjective evaluation of well being of the patients.

Aspiration of solid food particles into lungs of patients with gastroesophageal reflux and chronic bronchial disease

The existence of a relationship between upper digestive tract impairment and respiratory disturbance is generally accepted. The aim of this study was to determine whether pulmonary aspiration, documented by labeled meal and lung scans, could be a contributory factor. Thirty-two patients with chronic respiratory complaints (19 men, 13 women, mean age: 57.8 yr), 29 of whom had an FEV1 below 80 percent of predicted values, and 13 healthy subjects (six men, seven women, mean age 50.9 yr) took part in a prospective study. Scintiscans showed gastroesophageal reflux (GER) in 27 patients (84 percent) and in five control subjects (38 percent). Lung contamination was ascertained in 24 patients (75 percent) and in two control subjects (15 percent) (p less than 0.001) 15 hours after a labeled solid meal. Vegetal fibers were found in sputum smears after mouth rinsing the day after ingestion of 8.5 g wheat bran in 72 percent of patients and in 77 percent of control subjects. Although two associated phenomena are not necessarily causally related, pulmonary aspiration documented by pulmonary scintigraphy did significantly correlate with gastroesophageal reflux, suggesting that aspiration resulting from reflux may perpetuate, if not initiate, chronic bronchial disease.

Gastro-oesophageal reflux and childhood asthma: the acid test

The presence of gastro-oesophageal reflux was investigated in 18 children with moderate to severe asthma by overnight oesophageal pH monitoring. Appreciable reflux was found during sleep in eight; its relevance to nocturnal asthma was not clear. On another occasion the same children were challenged in a double blind fashion with a drink of dilute hydrochloric acid (0.001 N) and the response of the airways was monitored by peak flow measurements and by histamine challenge tests. There was a significant increase in mean histamine sensitivity (p = 0.001) 90 minutes after the acid drink without any associated change in baseline peak flow rate. Eight children had a significant response to the acid drink, and a further three reacted to a more concentrated solution (0.01 N). In those asthmatic children in whom reflux is associated with a positive response to an acid drink (five out of 18 in the present study) it seems likely that reflux exacerbates nocturnal symptoms.