Perception of Bronchoconstriction: A Complementary Disease Marker in Children with Asthma

Introduction. Asthma guidelines use symptoms as the most important aspect of asthma control. Symptom perception varies widely between individuals. Over-perception as well as underperception of bronchoconstriction could have a negative effect on asthma management. We hypothesized that perception of bronchoconstriction in childhood asthma is not related to common measures of disease control. For that reason, we examined the clinical determinants of the perception of bronchoconstriction and the repeatability of perception measurements. Patients and methods. In school-age children with moderately severe atopic asthma, we measured the perception of bronchoconstriction (decrease in forced expiratory volume in 1 second (FEV1)) during methacholine bronchoprovocation challenges. The perception of bronchoconstriction was assessed as the slope of the relation between FEV1 and Borg score, and as the Borg score at a 20% decrease in FEV1 from baseline during the provocation test (PS20). Data from subjects who had a 20% or more decrease in FEV1 (n = 112) were used for the analysis. Fifty-four children repeated the test after 3 months. Symptoms, use of rescue medication, and peak expiratory flows were scored in diaries during the 2 weeks before testing. Results. Symptom perception was significantly better in children without (PD20 > 1570 μg, n = 28) than in children with airway hyperresponsiveness (PD20 ≤ 1570 μg, n = 112), slope 0.22 versus 0.13 respectively (p < .001). Borg scores correlated with PD20 (p = .01), baseline FEV1 (only for slope, p = .04), and use of rescue beta agonist (p = .01), but not with other aspects of asthma control. Repeatability of Borg scores was good (slope: R = 0.59, PS20: R = 0.52). Conclusion. Poorer symptom perception in asthmatic children correlated with hyperresponsiveness, and was associated with lower baseline FEV1 and less use of rescue bronchodilators. This suggests that the measurement of symptom perception should be taken into account in individual management plans for children with asthma. CATO Study Group Members: Department of Pediatric Respiratory Medicine, Haga Hospital/Juliana Children’s Hospital, The Hague (M. Nuijsink, M.D., J. M. Kouwenberg, M.D.). Department of Epidemiology and Biostatistics, Erasmus University Medical Center, Rotterdam (W. C. J. Hop, Ph.D.). Department of Respiratory Medicine, Academic Medical Centre, University, Amsterdam (Prof. P. J. Sterk, Ph.D.). Leiden University Medical Center, Leiden (E. R. V. M. Rikkers-Mutsaerts, M.D.). Department of Pediatric Respiratory Diseases, University Medical Center Groningen (Prof. E. J. Duiverman, M.D., Ph.D.). Department of Pediatric Respiratory Medicine, Erasmus University Medical Center/Sophia Children’s Hospital, Rotterdam (Prof. J. C. de Jongste, M.D., Ph.D.). Asthma Center Heideheuvel, Hilversum (O. H. van der Baan-Slootweg, M.D., E. E. M. van Essen-Zandvliet, M.D., Ph.D.). Flevo Hospital, Almere (N. J. van den Berg, M.D., Ph.D.). Prof. Dr. J. M. Boogaard, Ph.D. Isala Klinieken, Zwolle (P. L. P. Brand, M.D. Ph.D., Ph.D., A. W. A. Kamps, M.D., Ph.D.). Medical Center, Alkmaar (G. Brinkhorst, M.D.). VU Medical Center, Amsterdam (J. E. Dankert-Roelse, M.D. Ph.D., A. F. Nagelkerke M.D.). Maxima Medical Center, Veldhoven (R. van Gent, M.D., Ph.D.). Maasland Hospital, Sittard (J. W. C. M. Heijnens, M.D.). University Hospital Maastricht (J. J. E. Hendriks, M.D., Ph.D., Q. Jöbsis, M.D., Ph.D.). University Medical Center/Wilhelmina Children’s Hospital, Utrecht (J. van der Laag, M.D., H. J. L. Brackel, M.D., Ph.D.). Academic Medical Center, Amsterdam (J. C. van Nierop, M.D.). Amphia Hospital, Breda (A. A. P. H. Vaessen-Verberne, M.D., Ph.D.) all from The Netherlands.