(Reuters Health) - A new U.S. study of groups of Latino youth with asthma sheds light on potential health disparities. Puerto Rican children were less likely than Mexican kids to use asthma inhalers regularly, researchers found.

In the year-long study, 123 Mexican and Puerto Rican children with asthma in Phoenix, Arizona and New York City received free inhalers that monitored their daily use of inhaled corticosteroids. These medicines help prevent asthma attacks and hospitalizations.

At check-up visits every three months, researchers found that 23 percent to 32 percent of the kids were using the inhalers for less than half of the prescribed doses - a level of adherence so poor that it puts kids at risk for serious asthma complications.

Puerto Rican children were more than five times more likely to have poor medication adherence than Mexican-American kids, the study found.

“Taking controller medications as prescribed reduces inflammation in the lungs and the potential for what we call airway remodeling which leads to poorer health outcomes,” said coauthor Kimberly Arcoleo of the University of Rochester School of Nursing.

“When children’s asthma is under good control as a result of consist use of their controller medications, they can live a normal life,” Arcoleo said by email. For example, she said, they can play in sports, they sleep better, and they do better in school.

Researchers also found that medication adherence can vary over time, and so it needs to be reassessed at each check-up, Arcoleo added.

Kids in the study who didn’t regularly take their asthma medicines were more likely to go to the emergency room or be hospitalized for asthma attacks than kids who used their inhalers most days, researchers reported in Annals of the American Thoracic Society.

Girls were more likely to miss medication doses than boys.

The study wasn’t designed to prove whether or how medication adherence might vary for Puerto Rican or Mexican children everywhere, nor to prove how adherence differences might lead to disparities in health outcomes. Also, researchers could only see 30 days of data on inhaler use at each check-up, so they lacked information on inhaler use at other times during the study.

It’s also possible that where kids received care accounted for some of the variation in medication use, said Dr. Avni Joshi, a pediatric allergy and asthma specialist at the Mayo Clinic in Rochester, Minnesota who wasn’t involved in the study.

The Puerto Rican children received care in hospital clinics, where patients may be sicker and have more severe disease, while most of the Mexican children were seen at mobile clinics or school-based asthma centers.

And fewer Puerto Rican children came from married households, which is also one of the strongest predictors of medication adherence for kids with health problems, Joshi said by email.

Parent education is critical for improving medication adherence, said Dr. Todd Mahr, president of the American College of Allergy, Asthma & Immunology.

“Many parents don’t believe controller medication is needed as the child will outgrow asthma,” Mahr, of Gundersen Health System in La Crosse, Wisconsin, said by email. “Also, there are still many parents that are concerned about side effects from the medication and the health care providers must convey that not treating the asthma puts the child at a higher risk than the medication.”

SOURCE: bit.ly/2TdVI7O Annals of the American Thoracic Society, online March 12, 2019.