That information comes from a study of children living in 42 health service districts in New York City, where asthma is the leading reason for hospital admissions of children under the age of 15.
Gina S. Lovasi, of the Institute for Social and Economic Research and Policy, and other New York City-based researchers at Columbia University discovered that children with more trees within a half mile radius of their home had a lower rate of asthma.
The study looked at asthma rates among children aged 4 to 5 and hospital admissions for the disease among children up to 15. Along with looking at the number of trees, the study also took into account sources of pollution, levels of affluence, and population density, all factors likely to influence the results, according to statement on the study released late Wednesday.
Researchers caution that the study should not be interpreted to mean that the number of trees in any community is tied to rates of childhood asthma there. But they do say that trees might help curb pollution and also encourage children to play outside and get more exercise.
Rates of childhood asthma in the U.S. soared by 50 percent between 1980 and 2000 and poor urban communities have seen the highest rates of the disease.
Results of the study were published online ahead of appearing in print in the "Journal of Epidemiology and Community Health."
