Antibiotic Prescription Rates for Acute Respiratory Tract Infections in US Ambulatory Settings

CONTEXT: During the 1990s, antibiotic prescriptions for acute respiratory tract infection (ARTI) decreased in the United States. The sustainability of those changes is unknown. OBJECTIVE: To assess trends in antibiotic prescriptions for ARTI. DESIGN, SETTING, AND PARTICIPANTS: The National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey data (1995-2006) were used to examine trends in antibiotic prescription rates by antibiotic indication and class. Annual survey data and census denominators were combined in 2-year intervals for rate calculations. MAIN OUTCOME MEASURES: National annual visit rates and antibiotic prescription rates for ARTI, including otitis media (OM) and non-ARTI. RESULTS: Among children younger than 5 years, annual ARTI visit rates decreased by 17% (95% confidence interval CI, 9%-24%), from 1883 per 1000 population in 1995-1996 to 1560 per 1000 population in 2005-2006, primarily due to a 33% (95% CI, 22%-43%) decrease in OM visit rates (950 to 634 per 1000 population, respectively). This decrease was accompanied by a 36% (95% CI, 26%-45%) decrease in ARTI-associated antibiotic prescriptions (1216 to 779 per 1000 population). Among persons aged 5 years or older, ARTI visit rates remained stable but associated antibiotic prescription rates decreased by 18% (95% CI, 6%-29%), from 178 to 146 per 1000 population. Antibiotic prescription rates for non-OM ARTI for which antibiotics are rarely indicated decreased by 41% (95% CI, 22%-55%) and 24% (95% CI, 10%-37%) among persons younger than 5 years and 5 years or older, respectively. Overall, ARTI-associated prescription rates for penicillin, cephalosporin, and sulfonamide/tetracycline decreased. Prescription rates for azithromycin increased and it became the most commonly prescribed macrolide for ARTI and OM (10% of OM visits). Among adults, quinolone prescriptions increased. CONCLUSIONS: Overall antibiotic prescription rates for ARTI decreased, associated with fewer OM visits in children younger than 5 years and with fewer prescriptions for ARTI for which antibiotics are rarely indicated. However, prescription rates for broad-spectrum antibiotics increased significantly.