Abstract
Background: Elevated blood eosinophils have been suggested to be associated with more exacerbations in adult asthmatics, but little is known of the relationship in children. We examined this relationship in a large Managed Care Organisation in Southern California.
Methods: We identified 556 asthmatic children ages 5-17 years who met the Health Effectiveness Data and Information Set criteria for persistent asthma in both 2009 and 2010 and had a blood eosinophil measure in 2010. Exacerbation was defined as an asthma emergency department visit/hospitalisation or an asthma outpatient visit requiring systemic corticosteroid within 7 days. Negative binomial regression was used to examine the association between blood eosinophil levels in 2010 using different cut-points and rates of exacerbation in 2011, adjusting for demographics, asthma burden and care, and co-morbidities.
Results: Higher blood eosinophil count (≥300 cells/µL) at baseline was associated with more exacerbations in 2011, after adjustment for multiple baseline variables. Other factors associated with increased exacerbations were history of asthma exacerbations and a younger age.
Conclusion: Elevated blood eosinophil was an independent risk factor for future asthma exacerbations in asthmatic children, suggesting a higher disease burden in asthma patients with elevated blood eosinophils.
- © 2014 ERS