Premium
Value of surrogate tests to predict exercise‐induced bronchoconstriction in atopic childhood asthma
Author(s) -
Lex Christiane,
Dymek Sabine,
Heying Ruth,
Kovacevic Alexander,
Kramm Christof M.,
Schuster Antje
Publication year - 2007
Publication title -
pediatric pulmonology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.866
H-Index - 106
eISSN - 1099-0496
pISSN - 8755-6863
DOI - 10.1002/ppul.20556
Subject(s) - medicine , exhaled nitric oxide , bronchoconstriction , spirometry , asthma , pulmonary function testing , plethysmograph , physical therapy , population , pediatrics , environmental health
Exercise challenge tests are helpful in the diagnosis and management of childhood asthma, but methodology is complex and time‐consuming. The aim of this study was to investigate whether exercise‐induced bronchoconstriction (EIB) can be predicted by the results of different surrogate tests in a pediatric population. Eighty‐five children (mean age: 11 years, range: 5–16 years) with atopic asthma were studied. Measurements of exhaled nitric oxide (eNO), spirometry and whole body plethysmography were performed followed by a standardized exercise testing. Questionnaires were completed asking for respiratory symptoms within 2 weeks preceding the study protocol. In 12/85 children (14%), forced expiratory volume in 1 sec (FEV 1 ) was significantly reduced by ≥15% after exercise testing. eNO was significantly elevated in this group of 12 patients as compared to patients without EIB (51.3 (31.1–67.3) parts per billion (ppb) versus 20.2 (10.9–42.3) ppb; P = 0.003). All children with normal eNO levels (≤25 ppb) had normal lung function results after exercise; hence the negative predictive value (NPV) of elevated eNO levels for prediction of EIB was 100%. However, the positive predictive value (PPV) was only 28%. The NPV and PPV for reported asthma symptoms within 2 weeks preceding the study were 96% and 26%, respectively. Considering recent symptom history in addition to elevated eNO improved the PPV to 40%, and resulted in the best combination of sensitivity and specificity. No baseline lung function parameter predicted whether a patient would develop EIB or not. In conclusion, eNO measurements, symptom questionnaires and most efficiently a combination of both surrogate tests can be used as time‐saving methods to exclude EIB in atopic childhood asthma. Pediatr Pulmonol. 2007; 42:225–230. © 2007 Wiley‐Liss, Inc.