Inappropriate use of antibiotics for acute asthma in United States emergency departments.

OBJECTIVES: The aim was to examine the use of antibiotics to treat asthma patients in U.S. emergency departments (EDs). The authors sought to investigate inappropriate antibiotic prescriptions by identifying the frequency and predictors of antibiotics prescribed for asthma exacerbations using data from two sources, the National Hospital Ambulatory Medical Care Survey (NHAMCS) and the National Emergency Department Safety Study (NEDSS).

METHODS: The authors used data from NHAMCS and NEDSS to identify the proportion of ED visits for asthma exacerbations that resulted in the prescription of an antibiotic. NHAMCS provided national data from 1993 through 2004, while NEDSS provided data from 63 primarily academic EDs from 2003 through 2006. Univariate analysis and multivariate logistic regression modeling were used to identify variables associated with antibiotic administration.

RESULTS: Analysis of NHAMCS data revealed that 22% (95% confidence interval [CI] = 20% to 24%) of acute asthma visits resulted in an antibiotic prescription from 1993 through 2004, with no significant change in prescribing frequency over the 12-year period. NEDSS data from 2003 through 2006 showed that 18% (95% CI = 17% to 19%) of acute asthma cases in academic EDs received an antibiotic. Multivariate modeling of NHAMCS data revealed that African American patients (odds ratio [OR] = 0.8; 95% CI = 0.6 to 0.97) and patients in urban EDs (OR = 0.5; 95% CI = 0.4 to 0.7) were less likely to receive antibiotics for asthma exacerbations than white patients and patients in nonurban EDs, respectively. NHAMCS analysis also found that patients in the South were more likely to receive antibiotics than those in the Northeast (OR = 1.4; 95% CI = 1.1 to 1.9). A NEDSS multivariate model found a similar difference, with African Americans (OR = 0.6; 95% CI = 0.4 to 0.8) and Hispanics (OR = 0.6; 95% CI = 0.4 to 0.8) being less likely than whites to receive an antibiotic.

CONCLUSIONS: ED treatment of acute asthma with unnecessary antibiotics is likely to contribute to bacterial antibiotic resistance. Interventions are needed to reduce inappropriate antibiotic prescriptions and to address disparities in asthma care.