Is the Increased Incidence of Asthma in HIV Positive Children Treated with HAART Due to Immune Reconstitution?

Asthma is a disease in which inflammation of the airways causes airflow into and out of the lungs to be restricted. The muscles of the bronchial tree become tight and the lining of the air passages swells, reducing airflow and producing the characteristic wheezing sound. This is known as an asthma attack.

There is widespread agreement that immune reconstitution, or CD4 cell recovery, in HIV positive patients treatment with HAART appears to provoke inflammatory diseases (often called immune reconstitution inflammatory syndrome, or IRIS).

In the current study, published in the July 2008 Journal of Allergy and Clinical Immunology, researchers sought to determine whether HIV positive children receiving HAART have a higher incidence of asthma than HIV positive children not receiving HAART.

The study included 2664 children (193 HIV positive and 2471 HIV negative) born to HIV positive mothers in the multicenter Women and Infants Transmission Study. The children were evaluated for the incidence and prevalence of asthma (i.e., asthma medication use) and changes in CD4 cell percentage over time.

Results

• The HIV positive children on HAART had higher CD4 cell percentages, lower CD8 cell percentages, and lower viral loads compared with HAART-untreated HIV positive children (P <0.05 to <0.01).

• The cumulative incidence of asthma medication use in HAART-treated HIV positive children at 13.5 years increased to 33.5%, versus 11.5% in HIV positive children not receiving HAART (hazard ratio 3.34; P = 0.01), and was equal to that in the HIV negative children.

• In children born before the HAART era, the prevalence of asthma medication use for HIV positive HAART-treated children at 11 years of age was 10.4%, versus 3.8% for HIV positive HAART-untreated children (odds ratio 3.38; P = 0.02), and was equal to that of for HIV negative children.

• The rate of change of CD4 cells around the time of first use of asthma medication for was 0.81% per year for HIV positive HAART-treated children, compared with 1.43% per year for HIV positive HAART-untreated children (P = 0.01).

These results led the study authors to conclude that the increased incidence of asthma in HIV positive children treated with HAART "might be driven by immunoreconstitution of CD4+ T cells."

Department of Pediatrics, Allergy and Immunology Section, Baylor College of Medicine and Texas Children's Hospital, Houston, TX; Division of Infectious Diseases, Children's Hospital, Harvard Medical School, Boston, MA; Clinical Trials & Surveys Corporation, Baltimore, MD; Department of Pediatrics, University of Illinois at Chicago, Chicago, IL; Department of Pediatrics, State University of New York, Brooklyn, NY; Pediatric, Adolescent and Maternal AIDS Branch, National Institute of Child Health and Human Development, Bethesda, MD; Department of Pediatrics, Puerto Rico School of Medicine, San Juan, PR.

8/01/08

Reference
SB Foster, K McIntosh, B Thompson, and others. Increased incidence of asthma in HIV-infected children treated with highly active antiretroviral therapy in the National Institutes of Health Women and Infants Transmission Study. Journal of Allergy and Clinical Immunology 122(1):159-65. July 2008. (Abstract)