S. Rietveld et al., THE CAPACITY OF CHILDREN WITH AND WITHOUT ASTHMA TO DETECT EXTERNAL RESISTIVE LOADS ON BREATHING, The Journal of asthma, 33(4), 1996, pp. 221-230
Clinical observations and research with adults consistently showed tha
t subjective symptoms of asthma poorly reflect actual airway obstructi
on. The lack of accurate symptom perception poses a problem for medica
tion and management of asthma. The accuracy of airflow detection was s
tudied in 46 children with and 46 without asthma (aged 7-18 years). Th
ey breathed through a facemask and responded to load stimuli of differ
ent intensity. Sessions consisted of 10 blocks of 5 min, each with 10
stimuli presented. Experiment 1: Loads of increasing intensity present
ed to 36 children with and 36 without asthma. Seven asthmatics had a r
eliable detection threshold (just noticeable difference, jnd) analogou
s to approximate to 64% fall in forced expiratory volume in 1 sec (FEV
(1)). Ten normal controls had a jnd of approximate to 39% fall. Experi
ment 2: Loads randomly presented to 10 children with and 10 without as
thma. Four asthmatics had a jnd of approximate to 64% fall in FEV(1).
Six normal controls had a jnd of approximate to 39% fall. The results
demonstrated that children generally were poorly perceiving load stimu
li and that asthmatics were less accurate.