Predictors of severe exacerbations, poor asthma control, and β-agonist overuse for patients with asthma

J Allergy Clin Immunol Pract. Nov-Dec 2014;2(6):751-8. doi: 10.1016/j.jaip.2014.06.001. Epub 2014 Jul 25.

Abstract

Background: Predictors of asthma exacerbations, poor asthma control, or extreme β-agonist overuse may be of clinical utility in the management of asthma.

Objective: To investigate characteristics that predict subsequent adverse outcomes in asthma.

Methods: An independent 24-week, randomized controlled trial of 303 adult patients with asthma who are at risk, which compared the efficacy of SMART (single budesonide-formoterol inhaler as maintenance and reliever therapy) with a fixed-dose regimen with salbutamol as reliever ("Standard"). Inhaled medication use was measured by electronic monitoring. Baseline characteristics that were predictors of subsequent severe asthma exacerbations, poor asthma control (Asthma Control Questionnaire -5 score ≥1.5), and "extreme" β-agonist overuse (>16 budesonide-formoterol actuations/d in SMART and >32 salbutamol actuations/d in Standard) were assessed by multivariate analyses.

Results: FEV₁ % predicted (rate ratio [RR] 1.14 [95% CI, 1.03-1.27] per 10% lower), more previous exacerbations (RR 1.15 [95% CI, 1.01-1.31]), Standard therapy (RR 1.62 [95% CI, 1.07-2.47]), and female sex (RR 2.18 [95% CI, 1.29-3.67]) were associated with future severe exacerbations. Asthma Control Questionnaire--5 (regression coefficient 0.20 [95% CI, 0.13-0.27] per 0.5 points higher) and age (regression coefficient 0.09 [95% CI, 0.01-0.17] per decade older) were associated with future poorly controlled asthma. Higher reliever use (RR 1.63 [95% CI, 1.36-1.95] per categorical score in Asthma Control Questionnaire question no. 6), Māori ethnicity (RR 2.20 [95% CI, 1.43-3.38]) and FEV₁ % predicted (RR 1.16 [95% CI, 1.03-1.31] per 10% lower) were associated with future extreme β-agonist overuse.

Conclusion: Future severe asthma exacerbations, poor asthma control, and extreme β-agonist overuse are predicted by different baseline clinical and demographic characteristics and management approaches in at-risk asthma.

Keywords: Asthma; Electronic monitoring; Predictors; Risk; β-agonist.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Adrenergic beta-2 Receptor Agonists / administration & dosage*
  • Adrenergic beta-2 Receptor Agonists / adverse effects
  • Adult
  • Albuterol / administration & dosage*
  • Albuterol / adverse effects
  • Asthma / diagnosis
  • Asthma / drug therapy*
  • Asthma / physiopathology
  • Bronchodilator Agents / administration & dosage*
  • Bronchodilator Agents / adverse effects
  • Budesonide / administration & dosage*
  • Budesonide / adverse effects
  • Disease Progression
  • Drug Combinations
  • Ethanolamines / administration & dosage*
  • Ethanolamines / adverse effects
  • Female
  • Forced Expiratory Volume
  • Formoterol Fumarate
  • Glucocorticoids / administration & dosage*
  • Glucocorticoids / adverse effects
  • Humans
  • Lung / drug effects*
  • Lung / physiopathology
  • Male
  • Metered Dose Inhalers
  • Middle Aged
  • Multivariate Analysis
  • New Zealand
  • Odds Ratio
  • Prospective Studies
  • Risk Factors
  • Severity of Illness Index
  • Surveys and Questionnaires
  • Time Factors
  • Treatment Outcome

Substances

  • Adrenergic beta-2 Receptor Agonists
  • Bronchodilator Agents
  • Drug Combinations
  • Ethanolamines
  • Glucocorticoids
  • Budesonide
  • Albuterol
  • Formoterol Fumarate

Associated data

  • ANZCTR/ACTRN12610000515099