The No. 1 most challenging place to live with asthma in the United States for 2009 is …. St Louis. The Gateway City takes the top spot as decided by the Asthma and Allergy Foundation of America (AAFA) based on an analysis and scoring of 12 factors in the 100 largest US metro areas.

St Louis earned the ranking due in part to worse than average scores in crude death rate due to asthma (2.2%), higher than average pollen counts over the previous year, and the lack of "100-percent" public smoke-free laws, which many other large cities are enacting.

"For the last several years, I have seen an increase in the severity of asthma in our patients and how their life is affected by it," says Mario Castro, MD, MPH, professor of medicine and pediatrics, Washington University in St Louis. "The lack of a smoke-free public environment for our patients with respiratory problems, especially asthma, in St Louis is appalling. Our return to the No. 1 Asthma Capital ranking is very concerning news for St Louis asthma patients and physicians."

Last year, Knoxville, Tenn, ranked No. 1 while St Louis held the number nine spot. Although St Louis climbed eight spots in the 2009 rankings, the prevalence of asthma, both estimated and self-reported in the city decreased slightly over the last year.

The top 10 Asthma Capitals for 2009, considered to be the most challenging places to live with asthma, are:

1. St. Louis, Mo
2. Milwaukee, Wis
3. Birmingham, Ala
4. Chattanooga, Tenn
5. Charlotte, NC
6. Memphis, Tenn
7. Knoxville, Tenn
8. McAllen, Tex
9. Atlanta, Ga
10. Little Rock, Ark

This is the 6th year the AAFA has scientifically researched and evaluated conditions in the largest metropolitan areas in the United States and ranked them based on quality of life for people with asthma in each city. The full report can be found online.