Mild to moderate asthmatics and free running.
We analyzed the bronchial response to free running in 48 mild to moderate extrinsic asthmatics and 36 nonasthmatics and also studied the relation between the methacholine hyperresponsiveness (expressed as PC20) and the changes in peak flow (PEF) post-exercise in an asthmatic group. The highest bronchial response to exercise was observed in asthmatic patients 10 min after free running (17.93 +/- 13.37%) and was significantly different from the nonasthmatics (U = 156; p > 0.00001). The correlation study disclosed a high correlation (r > or = 0.6) between the PC20 values (expressed as logarithmic transformation) and the exercise response (percent drop in the PEF measured 10 and 15 min post-exercise) in asthmatic subjects. With receiver operator characteristic (ROC) curves we obtained, as an ideal point, a percentage change in PEF (PEFR) of 8% or more measured 10 min post-exercise which reached 79.1% sensitivity and 89.7% specificity. We think that this exercise challenge can be used for detection of airway hyperresponsiveness in mild to moderate asthmatics.
Arias Irigoyen
J
J
Private Allergology Center, Huelva, Spain.
D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000503:physiopathology*; D001980:Bronchi / Q000502:physiology; D001985:Bronchial Provocation Tests; D002648:Child; D006801:Humans; D008297:Male; D016210:Methacholine Chloride / Q000008:administration & dosage; D010366:Peak Expiratory Flow Rate / Q000502:physiology; D012372:ROC Curve; D012420:Running; D013997:Time Factors
D016210:Methacholine Chloride