Effect of inhaled beclomethasone dipropionate on isocapnic hyperventilation with cold air in asthmatics, measured with forced oscillation technique.
Isocapnic hyperventilation with cold air (IHCA) is a reliable technique for assessing indirect bronchial hyperresponsiveness in patients with asthma. Impedance measurement of the respiratory system by the forced pseudorandom noise oscillation technique is a sensitive technique to assess changes in bronchial tone after IHCA. The aim of this study was to evaluate the effect of 6 weeks of treatment with beclomethasone dipropionate, 1,000 microg x day-1, on IHCA in asthmatic patients, measured with both forced oscillation technique and flow-volume recordings. Forty patients with mild asthma were included in this double-blind, placebo-controlled parallel-group study. Stratification on the basis of sex was performed to overcome differences in airway diameter. At entry and every 2 weeks during the treatment period, IHCA was performed and patient diaries were evaluated. Characteristic changes in forced oscillation parameters after IHCA were observed in all patients. After 6 weeks of treatment, BDP-treated patients showed statistically significant differences in impedance measurements after IHCA, manifested by significant attenuation of resistance at 8 Hz (p<0.01), slope of the frequency-resistance curve (p<0.01), reactance at 8 Hz (p=0.01), and resonant frequency (f0) (p<0.02). Flow-volume recordings showed only a statistically significant change in the decrease of inspiratory vital capacity (IVC) (p=0.01). Furthermore, a significant correlation was observed between serum immunoglobulin E (IgE) levels and the effect of BDP on IHCA, measured with forced oscillation technique. In this study, beclomethasone dipropionate, 1,000 microg x day(-1) for 6 weeks, decreased indirect bronchial hyperresponsiveness as assessed by cold air bronchoprovocation in asthmatic patients. The forced oscillation technique proved a more sensitive method of detecting changes in bronchial tone than flow-volume recordings.
Pennings
H J
HJ
Dept of Pulmonology, University Hospital Maastricht, The Netherlands.
Wouters
E F
EF
D000328:Adult; D000403:Airway Resistance / Q000187:drug effects; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology*; D001507:Beclomethasone / Q000008:administration & dosage* / Q000627:therapeutic use; D016535:Bronchial Hyperreactivity / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D003080:Cold Temperature; D004311:Double-Blind Method; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D010366:Peak Expiratory Flow Rate
D018927:Anti-Asthmatic Agents; D001507:Beclomethasone