title: Evaluation of the National Heart, Lung, and Blood Institute guidelines impairment domain for classifying asthma control and predicting asthma exacerbations.
abstract: BACKGROUND
  Accurate assessment of asthma control may help predict future asthma exacerbations.
  
  
  OBJECTIVE
  To evaluate asthma guidelines impairment domain components as predictors of exacerbations in severe/difficult-to-treat asthma.
  
  
  METHODS
  Children (aged 6-11 years; n = 289) and adolescents/adults (aged ≥ 12 years; n = 2,094) with complete baseline and 12-month data from The Epidemiology and Natural History of Asthma Outcomes and Treatment Regimens study were included. Asthma was categorized as very poorly controlled, not well-controlled, and well-controlled using impairment domain components. Effects of omitting each component on very poorly controlled and not well controlled groups were examined. Multivariable logistic regression determined the relationship of components in predicting asthma exacerbations.
  
  
  RESULTS
  Omission of individual impairment domain components led to misclassification of asthma control in 11% to 39% of patients. A baseline exacerbation was the strongest independent predictor of exacerbation at month 12 in children (odds ratio = 2.94; P < .001) and adolescents/adults (odds ratio = 2.93; P < .001). In children, very poorly controlled asthma-based short-acting β2-agonist use was associated with a 2-fold higher exacerbation risk (odds ratio = 2.03; P = .011). In adolescents/adults, not well controlled or very poorly controlled asthma based on short-acting β2-agonist use (odds ratio = 1.49), lung function (odds ratio = 1.66), and the Asthma Therapy Assessment Questionnaire (odds ratio = 1.94) were also independent predictors of exacerbations (P < .001).
  
  
  CONCLUSIONS
  Although the combined use of individual components of the impairment domain increases the sensitivity of identifying patients at high risk for future asthma exacerbations, specific components may be more important than others in severe/difficult-to-treat asthma. Prior exacerbations, short-acting β2-agonist use, lung function, and (in adolescents/adults) the Asthma Therapy Assessment Questionnaire were independent predictors of exacerbations.
authors.affiliation: Department of Allergy, Kaiser Permanente Southern California, San Diego, California 92111, USA. Robert.S.Zeiger@kp.org
authors.forename: Robert S
authors.initials: RS
authors.lastname: Zeiger
authors.forename: Ashley
authors.initials: A
authors.lastname: Yegin
authors.forename: F Estelle R
authors.initials: FE
authors.lastname: Simons
authors.forename: Tmirah
authors.initials: T
authors.lastname: Haselkorn
authors.forename: Lawrence
authors.initials: L
authors.lastname: Rasouliyan
authors.forename: Stanley J
authors.initials: SJ
authors.lastname: Szefler
authors.forename: Bradley E
authors.initials: BE
authors.lastname: Chipps
mesh_terms: D000293:Adolescent; D058666:Adrenergic beta-2 Receptor Agonists / Q000627:therapeutic use; D000328:Adult; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology*; D002648:Child; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D054555:National Heart, Lung, and Blood Institute (U.S.); D017410:Practice Guidelines as Topic; D011379:Prognosis; D011446:Prospective Studies; D012129:Respiratory Function Tests; D012307:Risk Factors; D014481:United States
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists