Stability of phenotypes defined by physiological variables and biomarkers in adults with asthma

Abstract

Phenotypes determined by biomarkers are less stable than those defined by physiological variables, especially in severe asthmatics. The data also imply that definition of asthma phenotypes is improved by repeated measures to account for fluctuations in lung function, biomarkers and asthma control.

Clinical and biological characteristics of the French COBRA cohort of adult subjects with asthma

“…In this group, 34% of patients were also on OCS therapy (7.3% of the total asthmatic population), with a mean daily dose of 22 mg oral prednisone. Together, these observations indicate that the patients with severe asthma included in the COBRA cohort are among the most severe cases currently described in the literature [11][12][13][14][15].…”

“…Some European and US cohorts have already provided insights into novel asthma phenotypes, and have improved our understanding of the underlying pathological processes [12][13][14][15][16]. However, most studies conducted with these cohorts were cross-sectional or, when longitudinal, they included low numbers of patients in the cohort or limited numbers of examinations during follow-up [13][14][15].…”

Improving the diagnosis of eosinophilic asthma

“…After withdrawal from ICSs, 67% of patients had eosinophilic asthma, whereas after treatment with ICSs, only 39% had eosinophilic asthma [12]. This and other factors may explain why the eosinophilic phenotype is not consistent over time in some studies [13].…”

“…This was illustrated in the 328 patients of the severe asthma research programme (SARP) showing that the accuracy of blood eosinophils to predict sputum eosinophilia was low, leading to considerable misclassification of patients with eosinophilic or non-eosinophilic asthma. This low accuracy might be due to the high variability of blood eosinophil counts in patients with asthma, both in the short (24 h) and in the long (1 year) run [13,27]. So, merely for the diagnosis of 'eosinophilic asthma,' one single measurement of blood eosinophils does not seem to be of great value.…”

Nordic consensus statement on the systematic assessment and management of possible severe asthma in adults

“…Furthermore, it is important to mention that the phenotyping, endotyping, and selecting biomarkers for the personalized approach do not necessarily include single biomolecules, but rather be composed of properly selected constellations or signatures of proteins and other peptides, transcriptomes, genes, microRNAs [164] and metabolites [165,166]. Finally, there is a need for more evidence on the consistency of severe asthma phenotypes, throughout the clinical course of severe asthma [23,159,163,167–169]. …”