The University of Arizona

Tucson Children's Respiratory Study

For more than two decades, researchers with the Tucson Children's Respiratory Study (CRS) have been collecting extensive data about the respiratory health of more than 1,000 infants - many of whom are now approaching adulthood. By analyzing the massive amount of information collected from this large, multiethnic population, CRS researchers have contributed substantially to our national understanding of asthma and allergies in childhood and adolescence. Indeed, the research team has generated more than 60 original research articles in prestigious journals on the natural history of, risk factors for, and correlates of asthma. Because of its national significance, this project has been continuously funded by the National Heart, Lung, and Blood Institute of the National Institutes of Health, and it has received funding to support another five years of research

A particularly important finding of the CRS is that, although people may have an inherited predisposition to be allergic, events early in life - particularly during the first year - appear to strongly influence the development of asthma and allergies. Some events increase the risk; others decrease the risk. For example, researchers have found that levels of IgE (a marker of the ability to respond to allergens) at birth have no relation to later persistent wheezing and asthma; however, levels of IgE at one year after birth are related to wheezing and asthma. Also, they've found that early sensitization to a mold known as Alternaria resulted in an increased risk of developing asthma, while sensitization at a later age carried less risk. And they've found that girls ages 6 to 11 who have an increased body mass index have an increased likelihood of developing asthma in middle to late childhood.

The team has also found an environmental influence that seems to reduce the risk of asthma and wheezing in later childhood: exposure of an infant to other children, either through siblings or a group day care environment.

The CRS has provided evidence of the complex relationships between inherited predisposition, early life events, immune system responses, and evolving risks for the development and persistence of asthma through adolescence. This study continues to provide a powerful means of addressing fundamental questions about the relative roles of environmental exposures and familial factors in the development of asthma from birth through early adult life. Continued data collection and analysis will allow CRS to continue contributing to our understanding of this complex condition and to suggest strategies for prevention and treatment.

Primary focus: Immunology