Hospitalizations for asthma in an urban population: 1995-1999

Background: Asthma hospitalizations occur commonly. Many are preventable if asthma is well controlled. Medications and demographic factors affect asthma hospitalization rates. Recent studies suggest that inhaled long-acting beta-agonists (LABAs) may heighten risk of serious asthma exacerbation, particularly in African Americans. Objectives: To further our understanding of the greater asthma morbidity associated with African American race and to investigate possible risk associated with LABAs. Methods: In an ecologic analysis, asthma hospitalization rates in individuals aged 5 to 64 years were determined for Philadelphia zip codes in period 1 (1995-1997) and period 2 (1997-1999) and were studied for associations with asthma drug prescription rates, demographic factors, and numbers and types of asthma care providers. Results: Higher hospitalization rates were found in African Americans vs Caucasians (45.7 vs 7.6 per 10,000) and in 5- to 17-year-olds vs 18- to 34- and 35- to 64-year-olds (30.4 vs 11.9 and 13.7 per 10,000). Hospitalizations were correlated directly with prescriptions for inhaled short-acting beta-agonists (SABAs) in periods 1 (r(s) = 0.61) and 2 (r(s) = 0.60) and inversely with LABA prescriptions in periods 1 (r(s) = -0.56) and 2 (r(s) = -0.66). Higher SABA prescription rates were also correlated with greater proportions of African Americans per zip code in periods 1 (r(s) = 0.58) and 2 (r(s) = 0.53). At all poverty levels, African Americans had higher hospitalization rates than Caucasians. Asthma hospitalization was significantly associated with poverty area residence (relative risk [RR], 2.29) and with African American race (RR, 4.31) and age (RR, 1.15) as individual-level variables (P < .001, Poisson regression). Conclusions: These data do not support the contention that LABA exposure is a major cause of asthma morbidity. Risk of asthma hospitalization is strongly associated with being African American. Ann Allergy Asthma Immunol. 2009;103:128-133.