To the Editor.
—There has been speculation in the literature about the cause of the rising mortality rates from asthma. Several recent analyses have focused on increases in deaths from asthma in metropolitan areas. Two studies looked at Cook County, Illinois, and found up to 16.4 deaths attributable to asthma per million population for persons aged 5 to 34 years (1980 through 1988)1 compared with national asthma mortality rates for persons 5 to 34 years of 2.6 to 4.2 per million (1980 through 1987).2 It is theorized that occupational exposures in metropolitan areas may be one of the factors increasing death rates from asthma in the inner cities.We studied death certificates for the given occupation of those who died in Chicago between 1980 and 1988, with asthma listed as the cause of death or a contributing cause of death. The ages examined were 20 to 35 years.
DeMers MP, Orris P. Occupational Exposure and Asthma Mortality. JAMA. 1994;272(20):1575. doi:10.1001/jama.1994.03520200031020