Airway Differences May Explain Why Asthma Can Be More Serious for Blacks
Asthma is a chronic lung disease, and airway inflammation is a major component of asthma. The inflammation causes the airways to swell and become more sensitive, which eventually leads to symptoms such as wheezing and shortness of breath, according to the U.S. National Heart, Lung, and Blood Institute.
“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 study author Dr. Sharmilee Nyenhuis. She’s an allergy, asthma and immunology specialist at the University of Illinois at Chicago.
Blacks are two to three times more likely than whites to be hospitalized or die from asthma, and factors such as access to health care and living conditions don’t entirely explain that large difference, according to background information in the study.
The researchers analyzed samples of coughed-up fluids from 1,000 asthma patients nationwide. The samples were tested for a type of white blood cell called eosinophils.
The study found that black people were more likely than white people to have what is called eosinophilic airway inflammation — even if they took similar doses of asthma medications such as corticosteroids.
“Our findings of higher numbers of African-Americans with this type of inflammatory airway pattern suggests a mechanism that may account for more severe and difficult to control asthma in African-Americans,” Nyenhuis said in a university news release.
This eosinophilic airway inflammation in blacks may be associated with worsened asthma and a reduced response to corticosteroids, she added.
The results suggest that black people with eosinophilic airway inflammation may not benefit from increasingly active corticosteroid treatment. Instead, they may need other types of treatment, Nyenhuis said.
The study was published in the Journal of Allergy and Clinical Immunology.
The U.S. Centers for Disease Control and Prevention has more on asthma.
SOURCE: the University of Illinois at Chicago, news release, Jan. 6, 2017