Exacerbations of asthma: a descriptive study of 425 severe exacerbations. The FACET International Study Group

Am J Respir Crit Care Med. 1999 Aug;160(2):594-9. doi: 10.1164/ajrccm.160.2.9811100.


The identification, prevention, and prompt treatment of exacerbations are major objectives of asthma management. We looked at change in PEF, symptoms, and use of rescue beta-agonists during the 425 severe exacerbations that occurred during a 12-mo parallel group study (FACET) in which low and high doses of budesonide with and without formoterol were compared in patients with asthma. Oral corticosteroids were prescribed for severe exacerbations, the main study end point, defined as the need for a course of oral corticosteroids (n = 311) or a reduction in morning PEF of > 30% on two consecutive days. PEF, symptoms, and bronchodilator use over the 14 d before and after the exacerbation were obtained from diary cards. Exacerbations were characterized by a gradual fall in PEF over several days, followed by more rapid changes over 2 to 3 d; an increase in symptoms and rescue beta-agonist use occurred in parallel, and both the severity and time course of the changes were similar in all treatment groups. Exacerbations identified by the need for oral corticosteroids were associated with more symptoms and smaller changes in PEF than those identified on the basis of PEF criteria. Female sex was the main patient characteristic associated with an increased risk of having a severe exacerbation. Exacerbations may be characterized predominantly by change in symptoms or change in PEF, but the pattern was not affected by the dose of inhaled corticosteroid or by whether the patient was taking formoterol.

Publication types

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

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Bronchoconstriction / drug effects*
  • Bronchodilator Agents / administration & dosage*
  • Bronchodilator Agents / adverse effects
  • Budesonide / administration & dosage*
  • Budesonide / adverse effects
  • Delayed-Action Preparations
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Drug Administration Schedule
  • Drug Therapy, Combination
  • Ethanolamines / administration & dosage*
  • Ethanolamines / adverse effects
  • Forced Expiratory Volume / drug effects
  • Formoterol Fumarate
  • Humans
  • Middle Aged
  • Peak Expiratory Flow Rate / drug effects


  • Bronchodilator Agents
  • Delayed-Action Preparations
  • Ethanolamines
  • Budesonide
  • Formoterol Fumarate