Benefits of low-dose inhaled fluticasone on airway response and inflammation in mild asthma

• Published in: Respiratory medicine Vol. 103; no. 10; pp. 1554 - 1563
• Main Authors: Boulet, Louis-Philippe, Turcotte, Hélène, Prince, Philippe, Lemière, Catherine, Olivenstein, Ronald, Laprise, Catherine, Larivée, Pierre, Bégin, Paul, Laviolette, Michel
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.10.2009; Elsevier; Elsevier Limited
• Subjects: Administration, Inhalation; Adolescent; Adult; Airway hyperresponsiveness; Androstadienes - administration & dosage; Asthma; Asthma - drug therapy; Asthma - physiopathology; Biological and medical sciences; Bones, joints and connective tissue. Antiinflammatory agents; Bronchodilator Agents - administration & dosage; Chronic obstructive pulmonary disease, asthma; Compensation; Dose-Response Relationship, Drug; Double-Blind Method; Educational materials; Fees & charges; Female; Fluticasone; Forced Expiratory Volume - drug effects; Humans; Induced sputum; Low-dose inhaled corticosteroids; Male; Medical sciences; Methacholine inhalation test; Middle Aged; Mild asthma; Pharmacology. Drug treatments; Pneumology; Practice Guidelines as Topic; Pulmonary/Respiratory; Wages & salaries; Young Adult; ATS; European Community Respiratory Health Survey; FP; AHR; peak expiratory flows; PC 20; FEV 1/FVC; P; ECRHS; placebo; AM; provocative concentration inducing a 20% fall in FEV 1; Airway hyperresponsiveness; Methacholine inhalation test; forced expiratory volume in one second; morning; American Thoracic Society; PEF; Mild asthma; Low-dose inhaled corticosteroids; FEV 1; ratio of forced expiratory volume in one second/forced vital capacity; fluticasone propionate; ICS; evening; PM; Induced sputum; inhaled corticosteroids; Lung disease; Corticosteroid; Respiratory disease; Low dose; Inflammation; Fluticasone; Asthma; Inhalation; Sputum; Bronchus disease; Obstructive pulmonary disease; Inhalation test; Pneumology
• ISSN: 0954-6111; 1532-3064
• DOI: 10.1016/j.rmed.2009.02.015

Summary Rationale Current guidelines suggest that asthma should be controlled with the lowest dose of maintenance medication required. Objectives To evaluate the effects of a low dose of inhaled corticosteroid compared to a placebo, on airway inflammation and responsiveness in patients with mild symptomatic asthma. Methods In this randomized double-blind, placebo-controlled, parallel group study, we looked at the influence of inhaled fluticasone propionate 250 μg/day for 3 months followed by 100 μg/day for 9 months on airway inflammation and methacholine responsiveness in non-smoking subjects with mild allergic asthma. Subjects were evaluated at baseline and 3, 6, 9 and 12 months after treatments; a 2-week evaluation of respiratory symptoms and peak expiratory flow measurements was done before each visit. Results Fifty-seven subjects completed the 3-month study period. Airway responsiveness, expressed as the PC20 methacholine, increased by 0.27 and 1.14 doubling concentrations, respectively, in placebo-treated ( n = 33) and in fluticasone-treated ( n = 24) asthmatic subjects ( p = 0.03). An additional improvement in PC20 up to 2.16 doubling concentrations was observed in the fluticasone-treated group during the 9-month lower-dose treatment ( p = 0.0004, end of low-dose period compared with placebo). Sputum eosinophil counts decreased after 3 months of fluticasone 250 μg/day compared with placebo ( p < 0.0001) and remained in the normal range during the 9-month lower-dose treatment. Respiratory symptoms and peak expiratory flows did not change significantly throughout the study in both groups. Conclusion In mild asthma, keeping a regular minimal dose of ICS after asthma control has been achieved, may lead to a further reduction in airway responsiveness and keep sputum eosinophil count within the normal range.