Change in FEV1 and Feno Measurements as Predictors of Future Asthma Outcomes in Children. Martes 5 de febrero

Change in FEV1 and Feno Measurements as Predictors of Future Asthma Outcomes in Children.

Authors:

Fielding S1, Pijnenburg M2, de Jongste JC2, Pike KC3, Roberts G4, Petsky H5, Chang AB6, Fritsch M7, Frischer T7, Szefler S8, Gergen P9, Vermeulen F10, Vael R11, Turner S12.

1 Medical Statistics Team, Institute of Applied Health Sciences, University of Aberdeen, Aberdeen, Scotland.
2 Department of Paediatric Respiratory Medicine and Allergology, Erasmus MC, Sophia Children's Hospital, Rotterdam, the Netherlands.
3 Clinical and Experimental Science Academic Unit, University of Southampton, Southampton, England; Respiratory Critical Care and Anaesthesia Group, Institute of Child Health, University College London, London, England.
4 Clinical and Experimental Science Academic Unit, University of Southampton, Southampton, England.
5 Department of Respiratory and Sleep Medicine, Lady Cilento Children's Hospital, Queensland University of Technology, Brisbane, Australia.
6 Department of Respiratory and Sleep Medicine, Lady Cilento Children's Hospital, Queensland University of Technology, Brisbane, Australia; Child Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia.
7 Department of General Paediatrics, University Children's Hospital, Vienna, Austria.
8 Breathing Institute, Children's Hospital Colorado, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO.
9 National Institute of Allergy and Infectious Diseases, Bethesda, MD.
10 Pediatric Department, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium.
11 Department of Paediatrics, Antwerp University Hospital, Antwerp, Belgium.
12 Department of Child Health, University of Aberdeen, Royal Aberdeen Children's Hospital, Aberdeen, Scotland. Electronic address: s.w.turner@abdn.ac.uk.

Abstract:
BACKGROUND:
Repeated measurements of spirometry and fractional exhaled nitric oxide (Feno) are recommended as part of the management of childhood asthma, but the evidence base for such recommendations is small. We tested the hypothesis that reducing spirometric indices or increasing Feno will predict poor future asthma outcomes.

METHODS:
A one-stage individual patient data meta-analysis used data from seven randomized controlled trials in which Feno was used to guide asthma treatment; spirometric indices were also measured. Change in %FEV1 and % change in Feno between baseline and 3 months were related to having poor asthma control and to having an asthma exacerbation between 3 and 6 months after baseline.

RESULTS:
Data were available from 1,112 children (mean age, 12.6 years; mean %FEV1, 94%). A 10% reduction in %FEV1 between baseline and 3 months was associated with 28% increased odds for asthma exacerbation (95% CI, 3-58) and with 21% increased odds for having poor asthma control (95% CI, 0-45) 6 months after baseline. A 50% increase in Feno between baseline and 3 months was associated with 11% increase in odds for poor asthma control 6 months after baseline (95% CI, 0-16). Baseline Feno and %FEV1 were not related to asthma outcomes at 3 months.

CONCLUSIONS:
Repeated measurements of %FEV1 that are typically within the "normal" range add to clinical risk assessment of future asthma outcomes in children. The role of repeated Feno measurements is less certain because large changes were associated with small changes in outcome risk.

DOI: 10.1016/j.chest.2018.10.009