Effectiveness of inhaled corticosteroids in real life on clinical outcomes, sputum cells and systemic inflammation in asthmatics: a retrospective cohort study in a secondary care centre

Abstract

ObjectivesThe impact of inhaled corticosteroids (ICS) on eosinophilic inflammation in asthma is well established, but their effect in a real-life setting has not been extensively studied. Our purpose was to investigate the effect of ICS on airway and systemic inflammation as well as on clinical outcomes in patients with asthma from clinical practice.Design, setting and participantsWe conducted a retrospective analysis on asthmatics from a secondary care centre in whom ICS were initiated/increased (n=101), stopped/decreased (n=60) or remained stable (n=63, used as a control group) between two visits with available sputum and blood cell counts.ResultsThe median time between both visits ranged from 1 to 2 years. Initiating or increasing ICS (median variation (IQR): 800 (400–1200) µg beclomethasone equivalent dose per day) reduced sputum eosinophils and fractional exhaled nitric oxide (P<0.0001) and to a lesser extent blood eosinophils (P<0.0001), while withdrawing or decreasing ICS (median variation (IQR): 900 (500–1200) µg beclomethasone equivalentdose per day) resulted in increased sputum eosinophils (P=0.008). No change was found in patients with a stable dose. The effectiveness of ICS in improving asthma control, quality of life, forced expiratory volume in 1 s (FEV1), bronchial hyper-responsiveness and exacerbation rate was only observed in the eosinophilic phenotype (sputum eosinophils ≥3%, n=79). In non-eosinophilic asthmatics, stepping-down ICS resulted in an improvement in asthma control and quality of life, without any significant change in FEV1 (n=38).ConclusionsOur results confirm the effectiveness of ICS on eosinophilic inflammation in real life and demonstrate that their clinical benefit seems to be restricted to eosinophilic asthmatics. Our data also support a try for stepping-down ICS in non-eosinophilic asthmatics.

FEV1 decline in relation to blood eosinophils and neutrophils in a population-based asthma cohort

“…Airway eosinophilia is frequently observed in asthma but it is neither necessary nor sufficient for the development of the disease. However, the presence of eosinophils in sputum and blood can identify responders to inhaled or oral corticosteroids, [23][24][25] and they are an important marker in the management of asthma. The ICS users also had higher levels of eosinophils, and lower FEV 1 already at baseline.…”

Increase in blood eosinophils during follow-up is associated with lung function decline in adult asthma

“…Perhaps surprisingly, the change in sputum eosinophils was not associated with lung function decline. This may be explained by the fact that it represents a phenotype shown to be responsive to increase ICS both in controlled clinical studies and in real life [42,43]. Therefore, sputum eosinophils are often associated with improvement in FEV 1 when change in ICS dosing is appropriate.…”

Are type-2 biomarkers of any help in asthma diagnosis?

“…Having said that, it does not deny the clinical value of measuring T2 biomarkers in phenotyping asthma, once the diagnosis has been done [ 10 ]. Indeed, there is accumulating evidence that the response to inhaled corticosteroids is dependent on the type of airway inflammation, with both sputum eosinophils [ 10 , 11 ] and elevated F ENO [ 12 , 13 ] being predictive of good treatment responses. We previously showed that combining F ENO , blood eosinophils and IgE may help in identifying eosinophilic asthma in large and unselected populations with untreated and treated asthma [ 14 ].…”