Geographic variations in asthma mortality in Erie and Niagara counties, western New York, 1991-1996.

Abstract

Asthma is one of the most common chronic respiratory diseases in the United States.1 More than 5000 persons died from asthma in 1995, and the trends in asthma mortality have been increasing in the United States over the past 2 decades.2 This investigation focused on Erie and Niagara counties in western New York. These counties have a combined population of 1.2 million and, together, are classified as a metropolitan area. Asthma mortality data for 1991 to 1996 were obtained from the New York State Bureau of Biometrics. Asthma mortality was determined from death certificate information. SPSS (SPSS, Inc, Chicago, Ill) was used in conducting statistical analyses. All population rates were calculated per 100 000 persons. Between 1991 and 1996, 158 asthma deaths were recorded in western New York. Eighty percent of these deaths occurred in Erie and Niagara counties. Average ageadjusted annual mortality rates were 1.61 for Erie County and 1.53 for Niagara County. In comparison, New York State had an average annual rate of 2.48 asthma deaths per 100 000 population. The majority of deaths (58%) during 1991 to 1996 occurred among individuals 65 years or older. The highest mortality rate for the period was 2.49 (95% confidence interval [CI] = 1.60, 3.38) in 1995; this rate decreased to 1.90 (95% CI = 1.12, 2.68) in 1996. Women had higher asthma mortality rates than men in Erie and Niagara counties (see Table 1 ▶). TABLE 1— Deaths From Asthma in Erie and Niagara Counties, by Age Group and Sex, 1991–1996 The city of Niagara Falls had an average annual asthma mortality rate of 2.96, almost 3 times that of the remainder of Niagara County (see Table 2 ▶). The city of Lockport had an annual mortality rate of 3.05, more than that of the rest of Erie County (1.09 per 100 000). Two zip codes in Buffalo's east side (14211 and 14215) accounted for 25% of the mortality from 1991 to 1996. TABLE 2— Deaths From Asthma, by Area: Western New York, 1991–1996 As a region, western New York had mortality rates lower than those in most of New York State. However, regional grouping masks areas of high risk for mortality due to asthma. Mortality was greatest in the 2 most populous counties (i.e., Erie and Niagara) and rare in rural counties of western New York. In Erie and Niagara counties, mortality was greater in urban areas than in suburban or rural areas. Buffalo, the most urbanized area in the 2 counties, had the highest annual mortality rate, comparable to that of New York City. Buffalo accounts for 20% of western New York's population but was responsible for 50% of asthma mortality in the region during the study period. The 2 zip codes with the highest asthma mortality rates in Buffalo comprise areas with large African American populations.3 Many US cities have large minority populations living in poverty, among whom the prevalence and severity of asthma are high.4–6 Given the reversibility of asthma and the availability of effective treatment strategies, deaths due to asthma are avoidable. The present report provides a basis for targeting interventions and evaluating their effectiveness.