Distinct baseline features associated with hard-to-control asthma in youths
Hard-to-control asthma in children and adolescents is distinguished by significant baseline characteristics including bronchodilator responsiveness, nasal inflammation and allergy, according to study findings published in
Journal of Allergy and Clinical Immunology.
“Our study found striking differences in how children with asthma respond to treatment, and these were associated with clinical factors that can be identified from the start,” Jacqueline A. Pongracic, MD, lead researcher from Ann and Robert H. Lurie Children’s Hospital of Chicago and Northwestern University Feinberg School of Medicine, said in a news release about the study. “Being able to predict whether a child’s asthma will be easy or difficult to control will help us provide a more personalized treatment approach.”
To determine the distinguishing clinical features of hard-to-control asthma, Pongracic and colleagues conducted baseline assessments and bimonthly guideline-based management visits on 619 inner-city children with asthma aged 6 to 17 years over the course of one year. Participants were mainly of African American and Latino descent living in nine urban communities across the nation.
“One of the novel aspects of our study is that we evaluated children with asthma over an entire year, which allowed us to more accurately characterize their disease,” Pongracic said.
Patients treated with 500 μg or more of fluticasone daily with or without a long-acting β-agonist were identified as having hard-to-control asthma. Forty-four baseline variables that reportedly may contribute to asthma severity and response to treatment were evaluated.
Data showed that 40.9% of participants had hard-to-control asthma and 37.5% had easy-to-control asthma, whereas 21.6% did not show characteristics of either group.
The researchers determined that bronchodilator responsiveness was the most important distinguishing factor of hard-to-control asthma — children in the hard-to-control asthma group were twice as likely to respond to a bronchodilator than those in the easy-to-control asthma group. Nasal inflammation and allergy, particularly to mold, were also found to be important factors that affected asthma therapy response. These results emphasize that asthma management should include treatment of nasal symptoms, according to Pongracic and colleagues.
In addition, higher rates of exacerbations were observed in children with hard-to-control asthma. Their exacerbations peaked in the spring and fall and their symptoms were heightened at nighttime during fall and winter. Despite good adherence to the most intensive treatment, children with these distinguishing features of hard-to-control asthma did not improve in symptoms, exacerbations, lung function or pulmonary physiology and were unable to reduce their medication requirements over the year.
“Our findings emphasize the unique nature of hard-to-control asthma in children,” Pongracic concluded. “Performing selected key assessments early on may help identify which children are likely to need higher doses of daily medications and to benefit from management by a pediatric allergist or asthma specialist.” – by Alaina Tedesco
Disclosure: The researchers report funding by the National Institutes of Health.