Usefulness of impulse oscillometry for the assessment of airway hyperresponsiveness in mild-to-moderate adult asthma

Ann Allergy Asthma Immunol. 2015 Jul;115(1):17-20. doi: 10.1016/j.anai.2015.04.022.


Background: Impulse oscillometry (IOS) is a novel method of assessing airway resistance. IOS is rarely used in assessing airway resistance after bronchoprovocation in adult asthma.

Objective: To ascertain the degree of change in IOS measurements seen in patients with asthma undergoing bronchial challenge testing.

Methods: Patients 18 to 65 years old with mild to moderate asthma, forced expiratory volume in 1 second (FEV1) greater than 80% predicted, and diurnal FEV1 variation less than 30% and taking inhaled corticosteroid (≤1,000 μg/day of beclomethasone dipropionate equivalent dose) were recruited. Sequential spirometry and IOS results were measured during bronchial challenge testing to inhaled methacholine and histamine.

Results: The magnitude of percentage of change demonstrated in total airway resistance at 5 Hz was greater than that observed for FEV1 in the 2 bronchial challenge tests. For example, at a methacholine provocation concentration that caused a decrease in FEV1 of 20%, a 43.5% change (95% confidence interval 29.4-57.5) was seen in total airway resistance at 5 Hz as measured by IOS compared with a 23.3% change (95% confidence interval 18.7-27.9) in FEV1. The magnitude of change seen with other IOS outcomes, including peripheral airway resistance, area under the curve, and resonant frequency, also was greater compared with spirometry.

Conclusion: The potential application of IOS in the assessment of airway hyperresponsiveness in adult asthma has been demonstrated. Further population studies are required.

Trial registration: (NCT01074853).

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenal Cortex Hormones / therapeutic use
  • Adult
  • Aged
  • Airway Resistance*
  • Area Under Curve
  • Asthma / diagnosis
  • Asthma / drug therapy
  • Asthma / physiopathology*
  • Bronchial Hyperreactivity / diagnosis
  • Bronchial Hyperreactivity / physiopathology*
  • Bronchial Provocation Tests
  • Double-Blind Method
  • Female
  • Forced Expiratory Volume
  • Histamine
  • Humans
  • Male
  • Methacholine Chloride
  • Middle Aged
  • Oscillometry / methods*
  • Randomized Controlled Trials as Topic / statistics & numerical data
  • Retrospective Studies
  • Spirometry
  • Young Adult


  • Adrenal Cortex Hormones
  • Methacholine Chloride
  • Histamine

Associated data