0000000000214966
AUTHOR
V. Gutiérrez
Airway Responsiveness to Inhaled Acetaldehyde in Subjects with Allergic Rhinitis: Relationship to Methacholine Responsiveness
<i>Background:</i> Asthmatic subjects have an exaggerated airway response to inhaled acetaldehyde, but no information is available on airway responsiveness to this bronchoconstrictor agent in subjects with allergic rhinitis. <i>Objective:</i> The aim of this study was to determine the effect of inhaled acetaldehyde on lung function in nonasthmatic subjects with allergic rhinitis. <i>Methods:</i> A total of 78 adults (43 subjects with allergic rhinitis, 16 asthmatics and 19 healthy subjects) were challenged with increased concentrations of acetaldehyde and methacholine. The response to each bronchoconstrictor agent was measured by the provocative concentra…
Effect of Salmeterol on Seasonal Changes in Airway Responsiveness and Exhaled Nitric Oxide in Pollen-Sensitive Asthmatic Subjects
Objective Using a model of natural allergen exposure, we examined the effect of regular treatment with salmeterol on allergen-induced changes in airway responsiveness and exhaled nitric oxide (ENO). Design Double-blind, randomized, parallel-group study. Setting Specialist allergy unit in a university hospital. Patients Asthmatic patients sensitized to pollen allergens were randomly allocated to monotherapy with salmeterol (n = 14) or placebo (n = 13). Interventions Salmeterol, 25 μg, and placebo inhalers, two puffs bid, for 6 weeks. Measurements Spirometry, the level of a provocative concentration of a substance (methacholine) causing a 20% fall in FEV 1 (PC 20 ), the PC 20 level for adenos…
Relationship between airway sensitivity to adenosine 5' monophosphate and the shape of the concentration-response curve to methacholine in subjects with allergic rhinitis.
Abstract The objective of this study was to determine differences in airway sensitivity to adenosine 5′-monophosphate (AMP) between allergic rhinitis subjects with plateau and those without evidence of plateau on the concentration–response curves to methacholine. A total of 51 adults (38 subjects with allergic rhinitis and 13 healthy controls) were challenged with increasing concentrations of methacholine and AMP. The methacholine challenge was terminated when there was a 40% or more decrease in forced expiratory volume in 1 sec (FEV 1 ), whereas the AMP challenge was stopped when FEV 1 had fallen by more than 20%. A plateau for methacholine was detected in all 13 healthy controls and in 27…
Exhaled Nitric Oxide and Bronchial Responsiveness to Adenosine 5′-Monophosphate in Subjects With Allergic Rhinitis
Study objectives: To determine differences in exhaled nitric oxide (ENO) between subjects with allergic rhinitis with and without increased responsiveness to direct and indirect bronchoconstrictor agents. Study design: Cross-sectional study with the order of challenge tests randomized. Setting: Specialist allergy unit in a university hospital. Patients: Thirty-eight subjects without asthma with allergic rhinitis and 10 healthy nonatopic control subjects. Measurements and results: Participants were challenged with increasing concentrations of adenosine 5monophosphate (AMP) and methacholine. ENO was measured with the singleexhalation method. A positive response to both bronchoconstrictor agen…
Differences in sensitivity, maximal response and position of the concentration-response curve to methacholine between asthmatics, patients with allergic rhinitis and healthy subjects
The aim of this study was to detect differences in maximal response and position of the concentration-response curves to methacholine between asthmatics and subjects with allergic rhinitis. A total of 228 adults (107 mild asthmatics, 96 allergic rhinitics and 25 healthy control subjects) were challenged with methacholine. The test was interrupted when FEV1 dropped by more than 40% or when the highest concentration of methacholine (200 mg ml-1) had been administered. Concentration-response curves were characterized by their PC20 (concentration of methacholine that produced 20% fall in FEV1 = airway sensitivity), and if possible, by their EC50 (concentration of methacholine that produced 50% …
Bronchoconstriction induced by inhaled adenosine 5′-monophosphate in subjects with allergic rhinitis
Adenosine and its related nucleotide, adenosine 5′-monophosphate (AMP) induce bronchoconstriction in asthmatics, probably caused by histamine release from airway mast cells. The objective of this study was to determine the effect of inhaled AMP on lung function in subjects with allergic rhinitis.A total of 52 adults (28 subjects with allergic rhinitis, 14 asthmatics and 10 healthy subjects) were challenged with increasing concentrations of AMP and methacholine. Airflow was assessed after each concentration and the response to each bronchoconstrictor agent was measured by the provocative concentration required to produce a 20% fall (PC20) in forced expired volume in one second (FEV1).All 14 …
Effect of cigarette smoking on airway responsiveness to adenosine 5'-monophosphate in subjects with allergic rhinitis.
Study objectives: The objective of this study was to determine differences in airway responsiveness to adenosine 5-monophosphate (AMP) between smokers and nonsmokers with allergic rhinitis. Methods: A total of 41 adults with allergic rhinitis (16 smokers and 25 nonsmokers) were challenged with increasing concentrations of methacholine and AMP. Airflow was assessed after each concentration, and the response to each bronchoconstrictor agent was measured by the provocative concentration required to produce a 20% fall in FEV1 (PC20). Results: The geometric mean PC20 AMP values were significantly lower in smokers than in nonsmokers: 72.4 mg/mL (95% confidence interval [CI], 33.9 to 154.9) vs 204…
Modifications of airway responsiveness to adenosine 5'-monophosphate and exhaled nitric oxide concentrations after the pollen season in subjects with pollen-induced rhinitis.
s: To determine the effect of cessation of exposure to pollen on airway responsiveness to adenosine 5'-monophosphate (AMP) in subjects with pollen-induced rhinitis, and to explore the relationship between changes in airway responsiveness and changes in exhaled nitric oxide (ENO) levels.Subjects were studied during the pollen season and out of season.Specialist allergy unit in a university hospital.Fourteen subjects without asthma with pollen-induced rhinitis who showed bronchoconstriction in response to methacholine and AMP during the pollen season and 10 healthy nonatopic control subjects.In subjects with pollen-induced rhinitis, ENO concentrations, provocative concentration of agonist cau…
Airway Responsiveness to Adenosine 5′-Monophosphate and Exhaled Nitric Oxide Measurements
Objectives To investigate the utility of the determination of airway responsiveness to inhaled adenosine 5′-monophosphate (AMP) and exhaled nitric oxide (ENO) levels as markers for safely reducing the dose of inhaled corticosteroids (ICS) in patients with asthma well controlled with a moderately high ICS dose. Methods A total of 37 patients with asthma well controlled for at least 3 months by treatment with a moderately high ICS dose (beclomethasone dipropionate, 500 to 1,000 μg or equivalent daily) were included in the study. Patients were treated for a 2-week run-in (baseline) period with their usual dose of ICS. For the next 12 weeks, patients were treated with ICS at half the previous d…