title: Perception of bronchoconstriction: a complementary disease marker in children with asthma.
abstract: BACKGROUND
  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.
  
  
  METHODS
  In school-age children with moderately severe atopic asthma, we measured the perception of bronchoconstriction (decrease in forced expiratory volume in 1 second (FEV(1)) during methacholine bronchoprovocation challenges. The perception of bronchoconstriction was assessed as the slope of the relation between FEV(1) and Borg score, and as the Borg score at a 20% decrease in FEV(1) from baseline during the provocation test (PS(20)). Data from subjects who had a 20% or more decrease in FEV(1) (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 (PD(20) > 1570 μg, n = 28) than in children with airway hyperresponsiveness (PD(20) ≤ 1570 μg, n = 112), slope 0.22 versus 0.13 respectively (p < .001). Borg scores correlated with PD(20) (p = .01), baseline FEV(1) (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, PS(20): R = 0.52).
  
  
  CONCLUSIONS
  Poorer symptom perception in asthmatic children correlated with hyperresponsiveness, and was associated with lower baseline FEV(1) 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.
authors.affiliation: Department of Pediatrics Respiratory Medicine, Haga Hospital/Juliana Children's Hospital, The Hague, The Netherlands. m.nuijsink@hagaziekenhuis.nl
authors.forename: Marianne
authors.initials: M
authors.lastname: Nuijsink
authors.forename: Wim C J
authors.initials: WC
authors.lastname: Hop
authors.forename: Johan C de
authors.initials: JC
authors.lastname: Jongste
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Sterk
authors.forename: And Eric J
authors.initials: AE
authors.lastname: Duiverman
mesh_terms: D000293:Adolescent; D000420:Albuterol / Q000031:analogs & derivatives / Q000627:therapeutic use; D000730:Androstadienes / Q000627:therapeutic use; D018926:Anti-Allergic Agents / Q000627:therapeutic use; D001249:Asthma / Q000188:drug therapy / Q000503:physiopathology / Q000523:psychology*; D016535:Bronchial Hyperreactivity / Q000188:drug therapy / Q000503:physiopathology / Q000523:psychology*; D001985:Bronchial Provocation Tests; D016084:Bronchoconstriction; D001993:Bronchodilator Agents / Q000627:therapeutic use; D002648:Child; D004417:Dyspnea / Q000188:drug therapy / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D000068298:Fluticasone; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D010465:Perception; D000068299:Salmeterol Xinafoate
chemical_list: D000730:Androstadienes; D018926:Anti-Allergic Agents; D001993:Bronchodilator Agents; D000068299:Salmeterol Xinafoate; D000068298:Fluticasone; D000420:Albuterol