Dataset Information

Association of elevated fractional exhaled nitric oxide concentration and blood eosinophil count with severe asthma exacerbations.

ABSTRACT:

Background

Blood eosinophil count (BEC) and fractional exhaled nitric oxide (FeNO) concentration are established biomarkers in asthma, associated particularly with the risk of exacerbations. We evaluated the relationship of BEC and FeNO as complementary and independent biomarkers of severe asthma exacerbations.

Methods

This observational study included data from the Optimum Patient Care Research Database. Asthma patients (18-80 years) with valid continuous data for 1 year before FeNO reading,???1 inhaled corticosteroid prescription, and BEC recorded???5 years before FeNO reading were separated into cohorts. Categorisation 1 was based on the American Thoracic Society criteria for elevated FeNO concentration (high:???50 ppb; non-high:?9 cells/L; non-high:?9 cells/L). Categorisation 2 (FeNO concentration, high:???35 ppb; non-high:?ResultsIn categorisation 1, patients with either high FeNO or high BEC (n?=?200) had a numerically greater exacerbation rate (unadjusted rate ratio, 1.31 [95% confidence interval: 0.97, 1.76]) compared with patients in the reference group. Combination of high FeNO and high BEC (n?=?27) resulted in a significantly greater exacerbation rate (3.67 [1.49, 9.04]). Similarly, for categorisation 2, when both biomarkers were raised (n?=?53), a significantly greater exacerbation rate was observed (1.72 [1.00, 2.93]).

Conclusion

The combination of high FeNO and high BEC was associated with significantly increased severe exacerbation rates in the year preceding FeNO reading, suggesting that combining FeNO and BEC measurements in primary care may identify asthma patients at risk of exacerbations.

SUBMITTER: Price DB

PROVIDER: S-EPMC6702739 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Association of elevated fractional exhaled nitric oxide concentration and blood eosinophil count with severe asthma exacerbations.

Price David B DB Bosnic-Anticevich Sinthia S Pavord Ian D ID Roche Nicolas N Halpin David M G DMG Bjermer Leif L Usmani Omar S OS Brusselle Guy G Ming Simon Wan Yau SWY Rastogi Sarang S

Clinical and translational allergy 20190821

<h4>Background</h4>Blood eosinophil count (BEC) and fractional exhaled nitric oxide (FeNO) concentration are established biomarkers in asthma, associated particularly with the risk of exacerbations. We evaluated the relationship of BEC and FeNO as complementary and independent biomarkers of severe asthma exacerbations.<h4>Methods</h4>This observational study included data from the Optimum Patient Care Research Database. Asthma patients (18-80 years) with valid continuous data for 1 year before F ...[more]

PMID: 31452870

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Project description:BackgroundAlthough the efficacy of corticosteroid treatment in controlling asthma is widely accepted, its effectiveness is undermined by poor adherence. However, the optimal method for measuring adherence to asthma therapy remains unclear.ObjectiveTo perform a review of the literature reporting biological, objective methods for assessing adherence to inhaled or oral corticosteroids in asthma; we included studies reporting direct measurement of exogenous corticosteroids in blood, or the effect of adherence on exhaled nitric oxide.DesignWe searched three databases MEDLINE (using both PubMed and Ovid), the Cumulative Index of Nursing and Allied Health Literature (CINAHL) and Web of Science for articles published between January 1975 and July 2020. Quality of the studies was assessed using the National Institute of Health checklist.ResultsFrom 2850 screened articles, 26 fulfilled the inclusion criteria. Measurement of blood prednisolone with or without cortisol was used in eight studies as a measure of oral corticosteroid adherence, and fractional exhaled nitric oxide (FeNO) in 17 studies for inhaled corticosteroid adherence. Inhaled corticosteroids were measured directly in the blood in one study. By direct measurement of drug levels in the blood, adherence rates to oral corticosteroids ranged from 47% to 92%, although the performance and timing of the test were often not known, making interpretation of findings and serum prednisolone concentrations difficult. FeNO is generally lower in adherent than non-adherent patients, but no absolute cut-off can be proposed based on the available data. However, a fall in FeNO following supervised inhaled corticosteroid dosing could indicate previous poor adherence.Conclusions and clinical relevanceDespite prednisolone and cortisol levels commonly being used as adherence markers in clinical practice, further work is required to assess the influence of the dose and timing on blood levels. The promising findings of FeNO suppression testing should be explored in further prospective studies.

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Dataset Information

Association of elevated fractional exhaled nitric oxide concentration and blood eosinophil count with severe asthma exacerbations.

Background

Methods

Conclusion

Publications

Association of elevated fractional exhaled nitric oxide concentration and blood eosinophil count with severe asthma exacerbations.

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