(Reuters Health) – African-American children and young adults with a hard-to-treat type of asthma may have a more difficult time keeping symptoms in check when they have experienced racial discrimination, a recent study suggests.
Researchers asked 576 black youth in the U.S. with asthma whether they had been hassled, made to feel inferior or prevented from doing something because of their race, ethnicity, color or language in situations at school, in medical settings or at restaurants and stores. Roughly half of them reported experiencing some form of discrimination at some point in their lives.
When they had not experienced these forms of discrimination, the children and young adults were almost twice as likely to have well-controlled asthma than when they had, researchers report in the journal PLoS One.
“Discrimination is a form of stress, and thus, its effect on asthma may be all or mostly due to stress,” said study co-author Dr. Luisa Borrell, a public health and health policy researcher at the City University of New York.
“Racial or ethnic discrimination experiences could affect our response to medications by changing our airway tissues and mucous production,” Borrell said by email.
The link between symptom control and discrimination was even more pronounced for a subset of participants who had high levels of an immune-system signaling molecule known as tumor necrosis factor-alpha (TNF-alpha) in their blood. It is a protein that’s involved in inflammation and elevated in asthma patients who don’t respond well to standard medications.
Still, even among the participants with high TNF-alpha levels, the youth who didn’t experience discrimination were almost three times more likely to have well-controlled asthma symptoms than their peers who did experience racism.
To assess symptom control, researchers tested how participants responded to albuterol, an inhaled bronchodilator that is used as a rescue therapy to open inflamed airways when people have an asthma attack. People who have frequent attacks may also be prescribed corticosteroids to control their symptoms.
“In asthma that is well controlled, you would expect a low response to albuterol since the patient is not having a lot of symptoms and their airways are not inflamed,” said co-senior study author Dr. Neeta Thakur of the University of California, San Francisco.
“But in people who are not prescribed control medications, or are under-dosed, you might see a higher response,” Thakur said in a statement.
When researchers did lung function tests before and after giving participants albuterol, they found people who experienced discrimination had a bigger response to albuterol than those who didn’t.
The study wasn’t a controlled experiment designed to prove that discrimination directly worsens asthma symptoms.
Another limitation is the possibility that factors such as segregated neighborhoods, exposure to indoor or outdoor air pollution, violence in the community or other social and economic disadvantages might at least partially explain the connection between discrimination and asthma symptoms found in the study, the authors note.
“Race, ethnicity and social class are important proxies for unmeasured factors that influence health outcomes,” said Dr. Avni Joshi of the Mayo Clinic College of Medicine in Rochester, Minnesota.
“A child who is in a poor housing situation, is more likely to come from a less educated family, which in turn are likely to be low income with incomplete or poor health coverage and access to care,” Joshi, who wasn’t involved in the study, said by email. “It is in these families that the stress levels are likely high due to insecurities for food, money and perceived or actual discrimination in all spheres of life.”
Controlling stress, however, might help keep asthma symptoms in check, said Dr. Elizabeth Matsui of Johns Hopkins Children’s Center in Baltimore.
“The details of how stress leads to inflammation are not clear, but links between stress and inflammation have been shown repeatedly, and asthma is a disease characterized by inflammation in the lungs,” Matsui, who wasn’t involved in the study, said by email. “We know that stress is broadly a risk factor for worse asthma, so stress management to reduce stress is appropriate.”