Treatment with a combination of anti-HIV drugs, known as highly active antiretroviral therapy (HAART), can improve the immune systems of infected patients, but new research indicates that in young children this effect may increase the risk of asthma.
In asthma, an excess amount of inflammatory and immune cells are produced in the lungs. Thus, any condition that directly or indirectly increases these cells might have an unwanted effect. "Investigators have assumed that asthma is not a complication of pediatric HIV infection, because studies (conducted before HAART was introduced in the mid-1990s) did not detect the problem," senior author Dr William T. Shearer, at Texas Children's Hospital in Houston, told Reuters Health.
The reason was that without HAART, immune system T cells would drop, preventing an asthmatic reaction, he explained. "It was not until the era of HAART, which restored the (T cell) levels, that an increased incidence of asthma was noted."
Reporting in the Journal of Allergy and Clinical Immunology, the research team examined the rate of asthma in children born to HIV-positive women, including 193 children infected with HIV (113 treated with HAART and 80 never treated with HAART) and 2471 children who were HIV-negative. The rate of asthma medication use in HAART-treated children by age 13.5 years was 33.5 percent, compared with 11.5 percent in HIV-infected children not treated with HAART. The rate in HAART-treated children was only slightly higher than that in HIV-negative children, suggesting that untreated HIV infection may actually protect against asthma. Further analysis suggested that it was, in fact, the increase in T cell levels achieved with HAART that was to blame for the elevated asthma risk.
Until further studies are done to verify these findings, Shearer cautions doctors to be alert to the possibility that HAART may lead to asthma in children. They also need to educate parents about this possible adverse effect and start the child on a regular asthma treatment program if it occurs.