Lack of Response to Asthma Treatment Higher in African American Patients

Approximately25 million (8%) of the US population had asthma in 2009, and during the same period, 1 in 9 African Americans were found to have asthma—–the highest rate among nonwhite racial/ethnic groups. In a new study, investigators found that African Americans may be less responsive to asthma treatment and more likely to die from the condition.

Airway inflammation is one of the key components of asthma, and new treatment developments are becoming more personalized based on the patient’s specific type of airway inflammation, according to the study published in theJournal of Allergy and Clinical Immunology.

“Emerging evidence suggests that differences in airway inflammation can affect a patient’s response to treatment, but whether the patterns of airway inflammation vary across race has, until now, been very unclear,” said corresponding author Dr Sharmilee Nyenhuis.

Studies have shown that black men and women are 2 to 3 times more likely than whites to be hospitalized or die fromasthma. Although many factors contribute to the asthma burden in African Americans, including health care access and environmental exposures, the rates remain disproportionate even after social and environmental factors are taken into account.

A secondary analysis was conducted of more than 1000 sputum samples obtained from AsthmaNet and the Asthma Clinical Research Network, according to the study. The coughed-up fluid samples were from past clinical trial participants who were over the age of 12 with mild or moderate persistent asthma, and who had not smoked within the last year. The samples were then tested for the presence of eosinophils.

“Our findings of higher numbers of African Americans with this type of airway inflammatory pattern suggests a mechanism that may account for more severe and difficult to control asthma in African Americans,” Dr Nyenhuis said. “It follows that the persistence of eosinophilic airway inflammation in African Americans may be associated with asthma exacerbations and an impaired response to corticosteroids.”

The findings suggest that black patients with eosinophilic airway inflammation may not benefit from increasingly strong corticosteroid treatment, and the authors suggest that other targeted therapies may need to be researched as a potential treatment option for black patients with difficult-to-manage eosinophilic asthma.