HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Supplementary tables All Versions of this Article: 33/3/486    most recent 09031936.00106208v1 Alert me when this article is cited Alert me if a correction is posted Permissions Request Permissions Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Thamrin, C. Articles by Frey, U. Search for Related Content PubMed PubMed Citation Articles by Thamrin, C. Articles by Frey, U.

Fluctuation analysis of lung function as a predictor of long-term response to β₂-agonists

¹ Division of Respiratory Medicine, Dept of Paediatrics, Inselspital, University of Bern, and ² Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland. ³ Dept of Biomedical Engineering, Boston University, Boston, MA, USA, ⁴ Faculty of Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.

CORRESPONDENCE: C. Thamrin, Division of Paediatric Respiratory Medicine, Dept of Paediatrics, University of Bern, Inselspital, 3010 Bern, Switzerland. Fax: 41 316324807. E-mail: cindy.thamrin{at}insel.ch

Keywords: Asthma, β₂-adrenoceptor genotype, bronchodilators, fractals, peak expiratory flow

Received: July 14, 2008
Accepted October 8, 2008

The response to β₂-agonists differs between asthmatics and has been linked to subsequent adverse events, even death. Possible determinants include β₂-adrenoceptor genotype at position 16, lung function and airway hyperresponsiveness. Fluctuation analysis provides a simple parameter measuring the complex correlation properties of day-to-day peak expiratory flow. The present study investigated whether predicts clinical response to β₂-agonist treatment, taking into account other conventional predictors.

Analysis was performed on previously published twice-daily peak expiratory flow measurements in 66 asthmatic adults over three 6-month randomised order treatment periods: placebo, salbutamol and salmeterol. Multiple linear regression was used to determine the association between during the placebo period and response to treatment (change in the number of days with symptoms), taking into account other predictors namely β₂-adrenoceptor genotype, lung function and its variability, and airway hyperresponsiveness.

The current authors found that measured during the placebo period considerably improved the prediction of response to salmeterol treatment, taking into account genotype, lung function or its variability, or airway hyperresponsiveness.

The present study provides further evidence that response to β₂-agonists is related to the time correlation properties of lung function in asthma. The current authors conclude that fluctuation analysis of lung function offers a novel predictor to identify patients who may respond well or poorly to treatment.