Premium
A study of the association between exercise‐induced wheeze and exercise versus methacholine‐induced bronchoconstriction in adolescents
Author(s) -
Henriksen Anne Hildur,
Tveit Kjerst Hafstad,
Holmen Turid Lingaas,
SueChu Malcolm,
Bjermer Leif
Publication year - 2002
Publication title -
pediatric allergy and immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.269
H-Index - 89
eISSN - 1399-3038
pISSN - 0905-6157
DOI - 10.1034/j.1399-3038.2002.01034.x
Subject(s) - medicine , bronchoconstriction , wheeze , asthma , methacholine , exhaled nitric oxide , population , physical therapy , respiratory disease , lung , environmental health
Among asthmatics, exercise‐induced wheeze (EIW) is a frequent symptom, and 40–77% of asthmatics demonstrate exercise‐induced bronchoconstriction (EIB). In the North‐Trøndelag population‐based survey of 8,571 adolescents (YOUNG‐HUNT), 26% reported wheeze during the previous 12 months (current wheeze). Of those subjects, 50% reported EIW. The aim of the present study was to investigate the association between EIW and EIB in randomly selected adolescents with EIW as the only or predominant asthma‐like symptom, and to relate our findings to results from methacholine bronchoprovocation tests (MT) and measurements of exhaled nitric oxide (ENO). Sixty‐three subjects with current wheeze induced by exercise, but not by allergen exposure, were investigated using a treadmill exercise test (ET) and measurements of ENO. Fifty‐eight subjects completed a MT on a separate study day. EIB was defined as a fall of ≥ 10% in the forced expiratory volume in 1 second ( FEV 1 ) after exercise (Δ FEV 1 % ex ). Twenty‐one subjects (33%) had EIB and 33 (57%) had a positive MT. The degree of reported dyspnea during the ET was not correlated to the Δ FEV 1 % ex. The correlation between EIB and methacholine‐induced bronchoconstriction (MIB) was poor, and the Δ FEV 1 % ex was more pronounced in smokers than in non‐smokers. Moreover, ENO was not increased in subjects with positive vs. negative ET. Hence, EIW, when reported as the only or predominant asthma‐like symptom, was linked to EIB in only one‐third of the patients. We conclude that EIW is a poor predictor of EIB in epidemiological studies. The poor correlation between EIB and MIB indicates that these two tests measure different mechanisms of bronchial hyper‐responsiveness.