Detection of exacerbations in asthma based on electronic diary data: results from the 1-year prospective BIOAIR study.

Abstract

BACKGROUND:

Objective measures are required that may be used as a proxy for exacerbations in asthma. The aim was to determine the sensitivity and specificity of electronic diary data to detect severe exacerbations (SEs) of asthma. A secondary aim was to identify phenotypic variables associated with a higher risk of exacerbation.

METHODS:

In the BIOAIR study, 169 patients with asthma (93 severe (SA); 76 mild to moderate (MA)) recorded lung function, symptoms and medication use in electronic diaries for 1 year. Data were analysed using receiver-operator characteristics curves and related to physician-diagnosed exacerbations. Medical history and baseline clinical data were used to assess risk of exacerbation.

RESULTS:

Of 122 physician-diagnosed exacerbations, 104 occurred in the SA group (1.1 per patient/year), 18 in the MA group (0.2 per patient/year) and 63 were severe using American Thoracic Society/European Respiratory Society criteria. During exacerbations, peak expiratory flow (PEF) and forced expiratory volume in 1 s significantly decreased, whereas day and night symptoms significantly increased. An algorithm combining a 20% decrease in PEF or a 20% increase in day symptoms on 2 consecutive days was able to detect SEs with 65% sensitivity and 95% specificity. The strongest risk factors for SEs were low Asthma Control Questionnaire score, sputum eosinophils ≥ 3%, body mass index >25 and low quality of life (St George's Respiratory Questionnaire), with ORs between 3.61 and 2.22 (p<0.05).

CONCLUSIONS:

Regular electronic monitoring of PEF and asthma symptoms provides an acceptable sensitivity and specificity for the detection of SEs and may be suitable for personal internet-based monitoring of asthma control.

• Authors: Maciej Kupczyk, Shushila Haque, Peter J Sterk, Ewa Niżankowska-Mogilnicka, Alberto Papi, Elisabeth H Bel, Pascal Chanez, Barbro Dahlén, Mina Gaga, Mark Gjomarkaj, Peter H Howarth, Sebastian L Johnston, Guy F Joos, Frank Kanniess, Eleni Tzortzaki, Anna James, Roelinde J M Middelveld, Sven-Erik Dahlén, BIOAIR investigators
• Journal: Thorax (Thorax) Vol. 68 Issue 7 Pg. 611-8 (Jul 2013) ISSN: 1468-3296 [Electronic] England
• PMID: 23564399 (Publication Type: Comparative Study, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Bronchodilator Agents
• Glucocorticoids
• Budesonide

Topics

• Administration, Inhalation
• Adolescent
• Adult
• Aged
• Asthma (diagnosis, drug therapy, physiopathology)
• Bronchodilator Agents (administration & dosage, therapeutic use)
• Budesonide (administration & dosage, therapeutic use)
• Cross-Over Studies
• Disease Progression
• Drug Therapy, Combination
• Electronic Health Records (statistics & numerical data)
• Female
• Follow-Up Studies
• Forced Expiratory Volume
• Glucocorticoids (therapeutic use)
• Humans
• Male
• Middle Aged
• Peak Expiratory Flow Rate
• Prognosis
• Prospective Studies
• Quality of Life
• Sensitivity and Specificity
• Surveys and Questionnaires
• Time Factors
• Young Adult