Abstract
Lung function variability is a fundamental feature of asthma but has been difficult to quantify in children due to methodological limitations. We assessed the feasibility and clinical implications of overnight flow variability measurement at home using impedance pneumography in young children.
44 children aged 3–7 years with recurrent or persistent lower airway symptoms were recruited. Patients were divided into high- or lower-risk groups (HR and LR groups) based on their risk of asthma (modified Asthma Predictive Index), and a third group was formed of children who had a history of wheeze and who were treated with inhaled corticosteroids (ICS group). Tidal volume and the derived flow were recorded through skin electrodes using impedance pneumography at home during sleep. Quantities describing overnight change in expiratory flow–volume minimum curve shape correlation (CSRmin) and respiratory chaoticity (minimum noise limit (NLmin)) were derived.
Recordings were successful in 34 children. CSRmin differed between the HR and LR groups (p=0.002) and between the HR and ICS groups (p=0.003), indicating a stronger change in flow profile shape in the HR group. NLmin differed between the HR and LR groups (p=0.014), indicating momentarily lowered chaoticity in the HR group.
Impedance pneumography was found feasible for quantifying nocturnal lung function variability and the measured variability was associated with risk of asthma in young children.
Abstract
Impedance pneumography enables home monitoring of lung function variability relating to risk of asthma in children http://ow.ly/XFWtD
Footnotes
This article has been revised according to the correction published in the July 2016 issue of the European Respiratory Journal.
This article has supplementary material available from erj.ersjournals.com
Support statement: This study received grants from Tampere Tuberculosis Foundation, Helsinki University Research Funds, the Finnish Medical Foundation, Foundation for Paediatric Research, Foundation for Allergy Research, Finnish Society for Allergy and Immunology, Instrumentarium Science Foundation, Nummela Sanatorium Foundation, Finnish Funding Agency for Innovation and the Sigrid Juselius Foundation. Funding information for this article has been deposited with FundRef.
Conflict of interest: Disclosures can be found alongside the online version of this article at erj.ersjournals.com
- Received June 23, 2015.
- Accepted January 24, 2016.
- Copyright ©ERS 2016