Association between exhaled inflammatory markers and asthma control in children

Abstract

The relationship between exhaled inflammatory markers and asthma control in children is unclear. To explore the association between inflammatory markers in exhaled breath (fractional nitric oxide (FeNO), volatile organic compounds (VOCs), cytokines/chemokines) and asthma control. To assess whether exhaled inflammatory markers are able to discriminate between children with persistently controlled/uncontrolled asthma. 96 asthmatic children were followed-up in a one-year observational study. Every 2 months, the following parameters were assessed: asthma control, FeNO, lung function (forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC), exhaled VOCs, and cytokines/chemokines in exhaled breath condensate (EBC). Random Forest was used to analyse the relationship between exhaled inflammatory markers and asthma control. For each model, patients were randomly selected for a training set and validation set. To assess the accuracy of the classification models, receiver operating characteristic-curves (ROC-curves) were generated. No significant association was found between the exhaled inflammatory markers (FeNO, markers in EBC, VOCs) and asthma control (area under the ROC-curve 49%). However, 15 exhaled VOCs could discriminate between subgroups of children with persistently controlled and uncontrolled asthma during all clinical visits (area under the ROC-curve 86%). Adding FeNO and markers in EBC to this model, did not lead to a more accurate classification (area under the ROC-curve 87%). There was no association between exhaled inflammatory markers and asthma control in children. However, children with persistently controlled or uncontrolled asthma during the 12 month study period could be discriminated by a set of VOCs.

Exhaled breath profiles in the monitoring of loss of control and clinical recovery in asthma

“…The novelty of the present study is represented by the prospective follow‐up of breathomics in asthma patients during the loss and recovery of clinical control. Our data therefore extend previously published cross‐sectional data in adults and longitudinal data in children, demonstrating various accuracies in discriminating controlled and uncontrolled asthma by GC/MS analysis of exhaled breath. In addition, the present study independently confirms and extends previous data on eNose signals during loss of control by withdrawal and restoration of steroids in asthma by van der Schee et al Our data are demonstrating the longitudinal changes in eNose signal between baseline, loss of control and recovery, whilst relating those to the course of symptoms, lung function and inflammatory cell counts in sputum.…”

Breathomics from exhaled volatile organic compounds in pediatric asthma

“…The authors found no statistically significant association between asthma control levels and inflammatory markers. However, a model comprising of 15 VOCs could successfully discriminate between children with persistently controlled and uncontrolled asthma with good prediction accuracy (AUROC‐curve 86%) …”

“…The authors found no statistically significant association between asthma control levels and inflammatory markers. However, a model comprising of 15 VOCs could successfully discriminate between children with persistently controlled and uncontrolled asthma with good prediction accuracy (AUROC-curve 86%) 37. As mentioned earlier, one of the clinical objectives of VOCs in exhaled breath is the prediction of exacerbations in asthmatic children.Promising results on this topic have been reported byRobroeks et al 38 in 2013, and recently by van Vliet et al39 In a 1-year prospective study, F E NO, VOC profiles, lung function, and clinical symptoms were determined for a small group of 40 children with asthma, every 2 months.…”

“…However, for this purpose, samples should be collected at point of care, which is more complex than collection during research visits only. In order to investigate whether inflammatory markers in exhaled breath were associated with asthma control, van Vliet et al37 performed a longitudinal observational study in 96 asthmatic children.Children with asthma were prospectively followed-up for 1 year and every 2 months asthma control, lung function, and exhaled nitric oxide fraction (F E NO), VOCs and cytokines/chemokines were assessed. This prospective nature is a major strength of this study, since prospective breathomics data in general is limited, but was completely lacking at this topic.…”

Pediatric pulmonology year in review 2016: Part 2

“…Thus, they concluded that induced sputum is not reliable for assessing lower airway eosinophilic inflammation in preschool children. In a longitudinal observation study of 96 children aged 6‐18 years, asthma control assessed by the asthma control test (ACT) was compared with exhaled breath nitric oxide (NO) and volatile organic compounds (VOC); there was no association between these exhaled markers and ACT, though a subset of exhaled VOC were identified that could categorize children with controlled versus uncontrolled asthma . Thomas et al showed that agreement between metacholine challenge test results, exhaled nitric oxide, and quality of life was poor in children with asthma, emphasizing that these parameters show different aspects of the disease and only a composite evaluation using all these tools can give us the big picture.…”