Children on HIV treatment may face increased asthma risk
By Ruth SoRelle, M.P.H.
Asthma appears to be more common in children with HIV who take highly active treatment for that infection than in the population of youngsters who are uninfected, said researchers from Baylor College of Medicine and Texas Children's Hospital whose work appears in the current issue of Journal of Allergy and Clinical Immunology.
While he thinks more studies are needed to confirm his results, Samuel B. Foster, M.D., an instructor in pediatrics – allergy and immunology section at BCM, said his results indicate a need for doctors treating children with HIV (the human immunodeficiency virus that causes AIDS) to carefully screen for asthma. Managing their symptoms and the triggers of their disorder could decrease the need to prescribe asthma medicines that suppress the immune system in patients with already compromised immunity.
Discovering the problem
Foster said he actually became aware of the problem when he was working on a study of sleep and thinking problems in children with HIV. The study required that those with asthma be excluded.
"We had to exclude many of the children because their charts indicated that they had asthma," he said.
When he reviewed the charts to determine how many children with HIV being treated at Texas Children's had asthma, he found that 28 of 83 children under treatment at that time had been diagnosed with asthma; 35 were on inhalers designed to aid their breathing in an acute attack and 16 took daily preventive medicines for asthma.
Those percentages (from 33 percent for those with a diagnosis of asthma to nearly 20 percent for those on preventive asthma medications) are significantly above the 6 percent asthma rate seen in the general population.
"There has been an increase in asthma in the United States and around the world," said Foster. "What we are reporting is a higher prevalence (in children with HIV) than is being seen even now in the general population."
Finding the triggers
Problems with asthma were not seen prior to the emergence of highly active anti-retroviral therapies using two and three drugs that fight HIV at different points in its life cycle, said Foster. However, these drugs revive the immune system. An overactive immune response to triggers such as mold, pollen and animal dander is considered one of the major factors in asthma.
Foster does not know why children with HIV on active treatment appear to be more at risk for asthma. One theory is that it could be an interaction of HIV itself with the more potent immune system, producing a robust inflammatory response such as asthma. More studies are needed to determine the cause as well as to confirm his data, he said.
It is possible that the lessons learned from these studies may give clues to the general increase in the prevalence of asthma in children in the United States, a doubling in the past 20 years according to the Centers for Disease Control and Prevention.
Others who participated in the research include Drs. Mary E. Paul, Claudia A. Kozinetz, Charles G. Macias and William T. Shearer, all of BCM pediatrics.
Funding for this study came from the National Heart, Lung and Blood Institute, the National Institutes of Health and the Center for AIDS Research and the Training Program for Clinical Research on AIDS, both of which are NIH-funded.
