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D S Postma

Publications and source records attributed to D S Postma.

At least 19 recordsLinked to original sources
PubMed1992

A comparison of bronchodilator therapy with or without inhaled corticosteroid therapy for obstructive airways disease. Dutch Chronic Non-Specific Lung Disease Study Group.

BACKGROUND: The morbidity from obstructive airways disease (asthma and chronic obstructive pulmonary disease) is considerable, and the mortality rate is rising in several countries. It has been hypothesized that long-term improvement in prognosis might result from vigorous bronchodilator or antiinflammatory therapy. METHODS: In a multicenter trial we compared three inhalation regimens in which a beta 2-agonist (terbutaline, 2000 micrograms daily) was combined with a corticosteroid (beclomethasone, 800 micrograms daily), an anticholinergic bronchodilator (ipratropium bromide, 160 micrograms daily), or placebo. Patients with airways hyperresponsiveness and obstruction who were 18 to 60 years old were followed for 2 1/2 years. RESULTS: Of the 274 patients enrolled, 56 percent had allergies. The mean forced expiratory volume in one second (FEV1) was 64 percent of the predicted value. The mean PC20 (the concentration of inhaled histamine causing a 20 percent decrease in FEV1, a measure of hyperresponsiveness) was 0.26 mg per milliliter. Withdrawal from the study, due mainly to pulmonary symptoms, was less frequent in the corticosteroid group (12 of 91 patients) than in the anticholinergic-drug group (45 of 92 patients) or the placebo group (44 of 91 patients; P < 0.001). The mean FEV1 (+/- SE) increased by 10.3 +/- 1.3 percent of the predicted value in the corticosteroid group within three months and remained stable thereafter, whereas it did not change in the other two groups (P < 0.001). The PC20 increased by 2.0 doubling concentrations in the corticosteroid group but did not change in the other groups (P < 0.001). In the corticosteroid group, patients who did not smoke, who had allergies, or who were less than 40 years old benefited more from their treatment than did those who smoked, did not have allergies, or were over 40, but all subgroups of the corticosteroid group had improvement as compared with the anticholinergic-drug or placebo group. CONCLUSIONS: The addition of an inhaled corticosteroid--but not an inhaled anticholinergic agent--to maintenance treatment with a beta 2-agonist (terbutaline) substantially reduced morbidity, hyperresponsiveness, and airways obstruction in patients with a spectrum of obstructive airways disease.

Administration, Inhalation↗
PubMed1992

Pulmonary function in systemic lupus erythematosus is related to distinct clinical, serologic, and nailfold capillary patterns.

PURPOSE: The purpose of this study was to investigate whether systemic lupus erythematosus (SLE) patients with interstitial lung disease represent a particular subset of patients characterized by the presence of clinical, serologic, and nailfold capillary patterns overlapping scleroderma. PATIENTS AND METHODS: In 57 consecutive patients with SLE, a standardized detailed history was obtained and a physical examination performed, directed at signs and symptoms of connective tissue diseases, in particular scleroderma. Additionally, pulmonary function testing, chest radiography, radionuclide transit studies of the esophagus, nailfold capillary microscopy, and detailed serologic studies directed at the antigenic specificities of antinuclear antibodies were performed. Patients were divided into three groups based on the results of pulmonary function testing, i.e., normal lung function, restriction, or isolated impairment of diffusion. Clinical, serologic, and nailfold capillary microscopic findings were compared among these three groups. RESULTS: Twenty patients had normal lung function, 19 had restrictive lung function loss, and 9 had an isolated impairment of the diffusing capacity (T1,CO). Patients with obstructive lung disease (n = 9) were excluded from analysis. Sclerodermatous changes of the hands were associated with a restrictive lung function pattern. Interstitial changes on chest radiograph were associated with isolated impairment of T1,CO. Nailfold capillary abnormalities correlated with decreased T1,CO and Dm, the component of T1,CO representing the diffusing capacity of the alveolocapillary membrane. Antibodies to U1-RNA were associated with restrictive lung function and decreased T1,CO. CONCLUSION: We conclude that interstitial lung disease is present in a subset of SLE patients characterized by an increased prevalence of scleroderma traits and anti-(U1)RNA antibodies. Microvascular changes may contribute to the development of interstitial lung disease in SLE as well as in scleroderma.

Adult↗
PubMed1992

Blood eosinophil numbers and activity during 24 hours: effects of treatment with budesonide and bambuterol.

The effects of the inhaled corticosteroid budesonide and the oral long-acting beta-agonist bambuterol on circadian variation of blood eosinophil numbers, serum levels of eosinophil cationic protein (ECP), serum eosinophil chemotactic activity (ECA), and serum neutrophil chemotactic activity (NCA) were studied in two groups of patients with allergic asthma. Group 1 (n = 8) had a circadian variation of peak expiratory flow (PEF) 15% or greater, and group 2 (n = 9) had a circadian PEF variation less than 15%. Both groups were randomized and crossover treated for 4 weeks with (A) 0.4 mg budesonide at 8 AM and 8 PM, (B) 20 mg bambuterol at 8 PM, and (C) placebo. At the end of each period blood eosinophil numbers, ECP, ECA, and NCA were measured during 24 hours at 4-hour intervals. No significant differences in the inflammatory parameters could be observed between the groups, although eosinophil numbers tended to be higher in group 1 than in group 2. Highest eosinophil numbers were observed at night. Budesonide reduced both eosinophil numbers and ECP levels, especially at night; bambuterol had no effect on both variables. No circadian variation or treatment effects were observed for ECA and NCA. This study suggests a role for the eosinophil in the nocturnal worsening of asthma, and it demonstrates that budesonide produces, in contrast to bambuterol, a reduction of (nocturnal) eosinophil numbers and activity.

Adolescent↗
PubMed1992

Separate and combined effects of corticosteroids and bronchodilators on airflow obstruction and airway hyperresponsiveness in asthma.

We have investigated separate and interactive effects of corticosteroids and bronchodilators on airflow obstruction and airway hyperresponsiveness. Twelve allergic subjects with asthma were treated in a double-blind, crossover, randomized study with budesonide, 1.6 mg daily for 3 weeks, prednisone, 40 mg daily, for 8 days, and placebo. After each period, dose-response curves were measured on 4 study days with doubling doses of salbutamol, ipratropium, a combination of salbutamol and ipratropium, and placebo until a plateau in FEV1 was reached. A histamine challenge was then performed, and the provocation concentration causing a 20% fall in FEV1 (PC20) was calculated. The budesonide and prednisone regimens were equipotent. FEV1 was 81.2% of predicted after budesonide, 81.0% predicted after prednisone, and 67.5% predicted after placebo, bronchodilatation thus being 13.7% predicted (budesonide) and 13.5% predicted (prednisone). PC20 improved with 2.17 doubling concentrations (DCs) after budesonide, and 1.86 DCs after prednisone, compared with that of placebo. Salbutamol caused stronger bronchodilatation than ipratropium (26.2% versus 14.7% predicted) and a better protection against histamine challenge (3.95 versus 1.12 DC). The effects of corticosteroids and bronchodilators on FEV1 and PC20 were, in general, additive. This study emphasizes different modes of action on both airflow obstruction and airway hyperresponsiveness by corticosteroids and bronchodilators, and it demonstrates no enhancement of bronchodilator action by corticosteroids.

Adrenal Cortex Hormones↗
PubMed1992

Effects of budesonide and bambuterol on circadian variation of airway responsiveness and nocturnal symptoms of asthma.

Effects of the inhaled corticosteroid budesonide and the oral beta-agonist bambuterol on the nocturnal worsening of asthma were studied in patients with allergic asthma with a circadian peak expiratory flow variation greater than or equal to 15% (group 1, n = 8) and less than 15% (group 2, n = 9). Airflow limitation and airway responsiveness to histamine were measured during 24 hours after 4 weeks of treatment with (A) 0.4 mg budesonide at 8 AM and 8 PM, (B) 20 mg bambuterol at 8 PM, and (C) placebo, in a randomized, crossover design. Patients in group 1 had worse nocturnal symptom scores and a greater airway responsiveness than patients in group 2; in addition, patients in group 1 had a larger increase in responsiveness during the night (1.1 versus 0.6 doubling concentrations [DC]). Both budesonide and bambuterol improved responsiveness more at night than during daytime, thus decreasing circadian variation: at 4 AM, increases in PC20 were 2.0 DC after budesonide and 0.8 DC after bambuterol, compared with placebo. Bambuterol reduced circadian variation in FEV1, but in contrast to budesonide, did not improve 24-hour mean levels of FEV1 and PC20. Both drugs beneficially influenced nocturnal symptoms; the effects of budesonide were stronger than those of bambuterol. Our findings demonstrate that budesonide and bambuterol reduce nocturnal airway responsiveness and asthma symptoms and suggest a relationship between the degree of airway responsiveness and the presence of nocturnal symptoms of asthma.

Adolescent↗
PubMed1992

Atopy and bronchial hyperresponsiveness: exclusion of linkage to markers on chromosomes 11q and 6p.

Previous studies have reported a familial predisposition for the development of atopy, bronchial hyperresponsiveness and clinical asthma, and therefore have suggested the presence of a heritable component to these disorders. The specific contributions of genetic and environmental factors in the pathogenesis of allergic disease and asthma have not been determined although Cookson et al. [1] have postulated linkage between atopy and chromosome 11q. We have studied 20 families (two and three generations) ascertained through a proband identified as having asthma (90% were also allergic) during the period of time between 1962 and 1970. Of those who were originally skin test positive, 82% remained positive. All probands whose pulmonary function allowed retesting (FEV1 > 1.2 l) remained hyperresponsive to histamine. The children of these probands are now in the same age range as their parents when they were originally evaluated; 66% are atopic using criteria described by Cookson et al. (one or more positive skin tests > or = 2 mm, an elevated total serum IgE or a positive specific IgE) and 22% demonstrate bronchial hyperresponsiveness (PC20 FEV1) to histamine. Using the highly polymorphic marker INT2 (which maps 2 cM from p lambda MS.5 l on chromosome 11q) and atopy, we obtained a lod score of -2.00 at a recombination fraction of 0.12. In addition, because many studies have suggested an association between atopy and certain HLA antigens, we investigated the possibility of linkage between atopy and bronchial hyperresponsiveness and D6S105, a polymorphic marker on chromosome 6p, located 7 cM from HLA-DR. For this marker and atopy, we observed a lod score of -2.00 with a recombination fraction of 0.07.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Adrenergic response in children with asthma on exogenous stimuli.

In asthmatic children it was investigated whether the degree of impairment of the adrenergic response on exogenous stimuli is related to the magnitude of the 24-hour amplitude in airflow obstructions. Urinary-adrenaline and noradrenaline excretion after house dust mite (HDM) inhalation and after exercise was measured. Nine children with (group I), and nine without increased airflow obstruction overnight (group II) and nine age matched healthy children (group C) were included in the study. All patients showed an early obstructive reaction (EOR) after HDM challenge. Six children in group I and five in group II developed an EOR on exercise. A significant increase in urinary adrenaline excretion was observed after exercise in the control group (P < 0.05, values on the control and challenge day being 5.4 +/- 0.9 and 10.0 +/- 1.6 mumol/mol creat.). The same occurred for noradrenaline (P < 0.01, values being 28.2 +/- 2.5 and 49.0 +/- 5.7 mumol/mol creat.). Adrenergic response after both stimuli was impaired in the asthmatic groups, in group I more pronounced than in group II. Values from group I for adrenaline on the control day, HDM and exercise challenge were 6.0 +/- 0.8, 4.7 +/- 0.6, 6.0 +/- 1.0 and for noradrenaline 36.1 +/- 2.7, 27.2 +/- 2.3, 38.4 +/- 4.9 mumol/mol creat., respectively. Values from group II for adrenaline on these days were 5.6 42- 1.0, 3.7 42- 0.6 and 9.0 +/- 1.3 and for noradrenaline 28.3 +/- 3.2, 22.4 +/- 2.5, 41.3 +/- 5.9 mumol/mol creat., respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Interpretation of bronchodilator response in patients with obstructive airways disease. The Dutch Chronic Non-Specific Lung Disease (CNSLD) Study Group.

BACKGROUND: There is no agreement on how a bronchodilator response should be expressed. Ideally, the index used should be able to distinguish asthma from chronic obstructive lung disease and be independent of initial FEV1. METHODS: Two hundred and seventy four adults (aged 18-60 years) outpatients with obstructive airways disease were studied. Patients were divided into syndrome groups on the basis of a standardised history: asthma (n = 99), asthmatic bronchitis (n = 88), and chronic obstructive lung disease (n = 51); 36 subjects could not be attributed to any subgroup. FEV1 was measured before and 20 minutes after inhalation of 1000 micrograms terbutaline. Different expressions of bronchodilator response (delta FEV1) were compared with respect to their dependence on initial FEV1 and their efficacy in separating subjects with asthma from those with chronic obstructive lung disease. delta FEV1 was expressed as a percentage of initial FEV1 (delta FEV1%init), absolute value (delta FEV1[1]), percentage of predicted FEV1 (delta FEV1%pred), standardised residual (delta SR-FEV1), and percentage of maximal possible increase (delta FEV1%[pred-init]). RESULTS: delta FEV1%init was more dependent on initial FEV1 (p = -0.405) than delta FEV1[1] (r = -0.145), delta FEV1%pred (r = -0.166), and delta SR-FEV1 (r = -0.127). delta FEV1%[pred-init] reached infinity when initial FEV1 approached predicted levels. delta FEV1%pred had a higher likelihood ratio (1.71) for separating patients with asthma from those with chronic obstructive lung disease than other expressions of bronchodilator response. Asthmatic patients had larger mean bronchodilator responses than patients in other subgroups; this difference was largest for delta SR-FEV1 (F = 9.19) and delta FEV1%pred (F = 9.03); it was much smaller for delta FEV1%init (F = 5.89). Despite significant differences in mean response, there was a large overlap of individual responses between diagnostic subgroups. The bronchodilator response was continuously and unimodally distributed for all expressions. CONCLUSIONS: delta FEV1%pred appears to be the most useful method of expressing bronchodilator response, both for clinical and for research purposes. Reversibility of airways obstruction in response to a bronchodilator is a continuous variable and not a dichotomous triat. Any cut off level of a "positive" bronchodilator response is therefore arbitrary.

Adolescent↗
PubMed1992

Effects of corticosteroids on bronchodilator action in chronic obstructive lung disease.

BACKGROUND: Short term treatment with corticosteroids does not usually reduce airflow limitation and airway responsiveness in patients with chronic obstructive lung disease. We investigated whether corticosteroids modulate the effects of inhaled salbutamol and ipratropium bromide. METHODS: Ten non-allergic subjects with stable disease were investigated; eight completed the randomised, double blind, three period cross over study. Treatment regimens consisted of 1.6 mg inhaled budesonide a day for three weeks, 40 mg oral prednisone a day for eight days, and placebo. After each period cumulative doubling doses of salbutamol, ipratropium, a combination of salbutamol and ipratropium, and placebo were administered on separate days until a plateau in FEV1 was reached. A histamine challenge was then performed. RESULTS: At the end of placebo treatment mean FEV1 was 55.5% predicted after inhaled placebo, 67.9% predicted after salbutamol and 64.0% predicted after ipratropium. Compared with the results after the placebo period the FEV1 with salbutamol increased by 0.7% predicted after treatment with budesonide and by 0.7% predicted after treatment with prednisone; the FEV1 with ipratropium increased by 0.7% predicted after budesonide and by 4.8% predicted after prednisone; none of these changes was significant. After placebo treatment the geometric mean PC20 was 0.55 mg/ml after placebo, 1.71 mg/ml after salbutamol and 0.97 mg/ml after ipratropium. Compared with the placebo period the PC20 with salbutamol was increased by 0.86 doubling concentrations after treatment with budesonide, and by 0.67 doubling concentrations after prednisone; the PC20 with ipratropium increased by 0.03 and 0.34 doubling concentrations after budesonide and after prednisone respectively compared with placebo; none of these changes was significant. CONCLUSIONS: In non-allergic subjects with chronic obstructive lung disease short term treatment with high doses of inhaled or oral corticosteroids does not modify the bronchodilator response to salbutamol or ipratropium or the protection provided by either drug against histamine. Salbutamol produces greater protection from histamine induced bronchoconstriction than ipratropium.

Administration, Inhalation↗
PubMed1992

There is no activation of O2- production by alveolar macrophages and neutrophil polymorphonuclear leukocytes in rat lung transplants during the reimplantation response and acute rejection.

Activation of phagocytes (alveolar macrophages [AM] and neutrophil polymorphonuclear leukocytes [PMN]) can cause tissue damage in inflammatory lung diseases. In this study we investigated whether phagocytes contribute to the development of tissue damage in lung grafts histologically observed during two different processes: the reimplantation response and the acute rejection. Therefore, the number and profile of bronchoalveolar lavage (BAL) and blood phagocytes and their in vitro spontaneous and serum-treated-zymosan (STZ)-stimulated O2- production were assessed after allogeneic (BN to LEW) and syngeneic (LEW to LEW) transplantation of the left lung in rats. BAL PMN numbers increased during the reimplantation response, whereas during the late phase of the rejection process BAL AM and PMN numbers were increased. The O2- production by the BAL phagocytes and blood PMN were not increased at any stage. Strikingly, the STZ-stimulated O2- production by the BAL phagocytes was significantly impaired during acute rejection. Our data suggest that activation of the O2- production by bronchoalveolar phagocytes does not play an important role in the development of tissue damage in lung transplants during the reimplantation response and acute rejection. The impaired O2- production by alveolar phagocytes during acute lung rejection may contribute to the increased susceptibility for pulmonary infections after lung transplantation.

Animals↗
PubMed1992

Perception of airway obstruction in a random population sample. Relationship to airway hyperresponsiveness in the absence of respiratory symptoms.

Subjects with asymptomatic airway hyperresponsiveness in epidemiologic studies may have variable airway obstruction that is not perceived as dyspnea. We tested the hypothesis that such subjects are less likely to report an increase in dyspnea during histamine-induced bronchoconstriction than symptomatic hyperresponders. A random population sample of 412 middle-aged subjects was studied. Before and after a standardized histamine challenge test, subjects recorded Borg scores for dyspnea: any increase in Borg score was considered significant. More than 80% of hyperresponsive subjects (PC10 histamine < or = 16 mg/ml) had no symptoms. The presence of prechallenge dyspnea was related to increased airways responsiveness and current smoking. An increase in Borg score was associated with younger age, more severe airway responsiveness, atopy, and female sex. The level of and increase in the Borg score were not significantly related to level and change in airway caliber (FEV1). In hyperresponsive subjects (PC10 < or = 16 mg/ml), subjects who reported dyspnea, wheeze, or asthma were more likely to show an increase in Borg score during histamine provocation than asymptomatic subjects (adjusted odds ratio 4.01, 95% confidence interval 1.01 to 16.00, p = 0.049), after adjustment for age, sex, smoking habits, FEV1, and atopy. This suggests that asymptomatic hyperresponders may have variable airway obstruction that is not recognized as breathlessness.

Adult↗
PubMed1992

Comparison of three normal breathing techniques to assess reversibility of airway obstruction.

Measurement of forced expiratory volume in one second (FEV1) is generally used to assess airway obstruction. Function tests during normal breathing are used as complementary tests as well as alternatives. Studies have been done comparing the esophageal pressure method with body plethysmography, and respiratory acoustical impedance with body plethysmography. We have not found any other studies comparing all three methods in the same subject. It is not clear whether those tests contribute to the assessment of reversibility of airways obstruction. We addressed the following questions: (1) How does the response of FEV1 to an inhaled beta agonist (400 micrograms fenoterol) relate to the response of lung function tests during normal breathing? (2) Are values obtained with three normal breathing techniques comparable in assessing severity of obstruction? We collected these data in 17 patients. A significant correlation was found between airway resistance measured with any of the three methods. The scatter was large, both before and after bronchodilation. The reversibility by the three methods expressed as absolute values (before and after inhalation) were comparable. In order of preference it appears that acoustical impedance is to be preferred to esophageal pressure because of less discomfort to the patient, and to body plethysmography because of the lower cost of the apparatus. Acoustical impedance can be used to assess acute changes in bronchomotor tone.

Adult↗
PubMed1992

European Respiratory Society study on chronic obstructive pulmonary disease (EUROSCOP): hypothesis and design.

Chronic obstructive pulmonary disease (COPD) is a common disease in industrialised countries and responsible for a considerable morbidity and mortality. Cigarette smoking is the most important aetiological factor. The EUROSCOP trial aims at investigating the hypothesis that airway inflammation plays an important pathogenic role in the development of chronic obstructive airway disease in smokers. In cigarette smokers with poorly reversible airflow obstruction, the effect over 3 yrs of an inhaled glucocorticosteroid, budesonide 400 micrograms b.i.d., on the decline of lung function, measured as postbronchodilator forced expiratory volume in one second (FEV1), will be compared with that of placebo. The trial has been designed to detect a difference in yearly decline of at least 30 ml.year-1. The study is a parallel group, randomised, double-blind, multicentre study. Patients will be recruited from 47 centres in 12 countries in Europe. It will start with a run-in consisting of two 3 month periods. During the first 3 months, the patients will be offered a smoking cessation programme. All patients who have not stopped smoking during this period will enter the second half of the run-in where compliance with the dosage regimen will be tested. After these two periods, patients will be randomised to receive either inhaled budesonide, 400 micrograms b.i.d., or placebo for a period of 3 yrs.

Administration, Inhalation↗
PubMed1992

Long-term multicentre trial in chronic nonspecific lung disease: methodology and baseline assessment in adult patients. Dutch CNSLD Study Group.

Airways obstruction and airways hyperresponsiveness are two dominant features in patients with chronic nonspecific lung disease (asthma and chronic obstructive pulmonary disease (COPD)). We set up a study to determine whether long-term (3 yrs) therapeutic intervention directed at airways obstruction and hyperresponsiveness is superior to one directed at airways obstruction alone. Patients were selected on functional criteria (age, baseline forced expiratory volume in one second (FEV1), and airways hyperresponsiveness) and, furthermore, extensively characterized by history, smoking habits, allergy, reversibility of airways obstruction and quality of life. The methodology and practical problems of setting up this large multicentre study are outlined, together with an analysis of baseline data. Standardization of methods and techniques and recruitment of patients required much effort, recruitment taking about twice as long as expected. A 3 month feasibility study allowed us to eliminate minor problems in the protocol. Over a 16 month period, 274 adult patients (18-60 yrs) from the out-patient clinics of six university centres entered the study; 99 met the diagnostic criteria for asthma, 51 for COPD, 88 for asthmatic bronchitis, and 36 could not be classified. Their mean (SD) FEV1% pred was 65.1 (15.2)%. Their geometric mean provoking concentration of histamine producing a 20% fall in FEV1 (PC20 histamine) was 0.28 mg.ml-1. In a multiple regression analysis, more severe airways hyperresponsiveness was associated with lower prechallenge FEV1% pred (p less than 0.0001), higher pack-years of smoking (p = 0.0099), blood eosinophil count (p = 0.0004), skin test reactivity (p = 0.0047) and with female sex (p = 0.0302). We conclude that setting up long-term multicentre trials in chronic nonspecific lung disease (CNSLD) is feasible and that these may offer valuable information on treatment and outcome of the disease.

Adult↗
PubMed1991

Effect of positive expiratory pressure breathing in patients with cystic fibrosis.

The effect of positive expiratory pressure breathing, alone and in combination with coughing, was investigated in eight patients with cystic fibrosis. Functional residual capacity and total lung capacity was measured with a body plethysmograph before, during, and immediately after breathing with expiratory pressure of 5 and 15 cm H2O, and after a coughing period. The positive expiratory pressure breathing was carried out five times for two minutes with a two minute interval between each period. Mucus transport was measured in a peripheral lung region and over the whole lung by a radioactive aerosol tracer technique. Clearance measurements were carried out continuously during positive expiratory pressure breathing and during a control period. Two minutes' breathing with an expiratory pressure of 5 and 15 cm H2O caused an increase in mean (SEM) functional residual capacity from 2.6 (0.1) to 3.6 (0.3) and 4.4 (0.5) 1 and an increase in total lung capacity from 5.1 (0.2) to 5.9 (0.3) and 6.9 (0.4) 1. Lung volumes were higher during breathing with an expiratory pressure of 15 cm H2O than with 5 cm H2O; both returned to baseline values immediately after positive expiratory pressure breathing. Spontaneous mucus clearance and mucus clearance by coughing were not influenced by positive expiratory pressure breathing at either expiratory pressure. Thus in patients with cystic fibrosis positive expiratory pressure breathing increases lung volumes in relation to the expiratory pressure imposed; these changes in lung volume did not, however, lead to an improvement of mucus transport.

Adolescent↗
PubMed1991

Nocturnal airflow obstruction, histamine, and the autonomic central nervous system in children with allergic asthma.

A study was carried out to investigate whether an imbalance in the autonomic nervous system or release of histamine, or both, is responsible for the nocturnal increase in airflow obstruction in asthmatic children. The study comprised 18 children with allergic asthma, nine with (group 1) and nine without (group 2) nocturnal airflow obstruction, and an age matched control group. All drugs were withheld for three days before and during the study. On day 4 each child was admitted to hospital and a series of measurements was made every four hours for 24 hours. These included measurements of the forced expiratory volume in one second (FEV1), heart rate and sinus arrhythmia gap from an electrocardiogram (an indirect measure of parasympathetic activity) and urine sampling for determination of catecholamine and N'-methylhistamine concentrations (measures of sympathetic activity and histamine release respectively). Urinary N'-methylhistamine excretion was significantly higher over the 24 hours in children in group 1 than in children in group 2, and overnight values were also significantly higher in children in group 1 than those in group 2. Mean (SEM) values (mumol/mol creatinine) were 154.6 (11.2) in group 1 and 110 (11.2) in group 2 for 2400-0400 hours samples and 139.2 (13.1) and 101.2 (10.6) 0400-0800 hours samples. There was no evidence of decreased sympathetic or increased parasympathetic activity in association with the nocturnal airflow obstruction; noradrenaline concentrations were increased in group 1. These observations indicate that nocturnal airflow obstruction is associated with increased release of histamine overnight.

Adolescent↗