Severe Asthma Research - September 2016
Christina E Ciaccio, MD, MSc
Assistant Professor of Pediatrics
University of Chicago Medicine
Comer Children’s Hospital
Chicago, Illinois, United States
Inflammatory and Co-Morbid Features of Patients with Severe Asthma and Frequent Exacerbations.
This study used data from the Severe Asthma Research Program-3 (SARP-3) to determine characteristics of asthmatics who are exacerbation-prone (EPA), defined at >3 asthma exacerbations per year. SARP-3 recruited patients with asthma ages six and older. By design, 25% of patients recruited were children and 60% had severe asthma. Data on asthma risk, control, exacerbations and healthcare utilization was collected. SARP-3 recruited 709 patients which included 187 children and 173 patients who were exacerbation-prone. In total, 37% of those without any exacerbations had severe asthma and 12% of those with EPA did not have severe asthma. Those with EPA compared to those without exacerbations had no difference in sex, race, or ethnicity. Those with EPA were prescribed more controller medications, but had similar compliance with medications compared to those without exacerbations. Those with EPA had the lowest lung function on average; however, 16% of adults and 24% of children with EPA had FEV1%>80% and 25% of adults with an FEV1%<60% had no exacerbations. Blood eosinophil levels did not defer among groups. Sputum eosinophils were lower in adults without exacerbations but not children. Sputum neutrophils and exhaled nitric oxide did not differ between those with EPA and those with no exacerbations. IgE levels were lowest in those with EPA. Those with EPA compared to others had more comorbidities, including hypertension, sleep apnea, osteoporosis, diabetes, and particularly GERD and chronic sinusitis. A multivariate model using SARP1+2 data showed that blood eosinophils, GERD, BMI, and sinusitis were associated with EPA. This large and well-executed study describes those with exacerbation-prone asthma in great detail and provides evidence that EPA is a distinct phenotype of asthma.
Denlinger LC, Phillips BR, Ramratnam S, Ross K, Bhakta NR et al. Inflammatory and Co-Morbid Features of Patients with Severe Asthma and Frequent Exacerbations. American Journal of Respiratory and Critical Care Medicine 2016; published online ahead of print, August 24. (doi:10.1164/rccm.201602-0419OC)