Background: The rate of mortality from asthma has increased substantially in the United States since 1978. We analyzed the patterns of the rates of death from asthma in Philadelphia between 1969 and 1991.
Methods: The rates of death from asthma were analyzed and compared with trends in the concentrations of major air pollutants: ozone, carbon monoxide, nitrogen dioxide, particulate matter (particles < 10 microns in diameter), and sulfur dioxide. Univariate and multivariate analyses were used to study the rates of death from asthma from 1985 to 1991 and their association with race, poverty, sex, and other factors.
Results: The rate of death from asthma decreased from 1.68 per 100,000 people in 1969 to 0.68 per 100,000 in 1977, but then increased to 0.92 per 100,000 in 1978 and 2.41 per 100,000 in 1991. Between 1965 and 1990, the concentrations of major air pollutants declined substantially. From 1985 to 1991, 258 people were identified for whom asthma was the primary cause of death. According to multivariate analysis, the rates of death from asthma from 1985 to 1991 were significantly higher in census tracts with higher percentages of blacks (P = 0.032), Hispanics (P = 0.013), female residents (P < 0.001), and people with incomes in the poverty range (P < 0.001).
Conclusions: The rates of death from asthma have increased in Philadelphia, whereas concentrations of major air pollutants have declined. The rates are highest in census tracts with the highest percentages of poor people and minority residents, particularly blacks. Public health efforts should target urban areas where the risk of death from asthma is highest.