Physicians often prescribe 10-day courses of antibiotics for acute bacterial sinusitis, which is considerably longer than recommended by evidence-based guidelines designed to limit antibiotic resistance, according to a new study from the Centers for Disease Control and Prevention (CDC).
CDC researchers estimate that almost 70% of antibiotic prescriptions for sinusitis in 2016 specified a 10-day course or longer, according to their research letter published yesterday in JAMA Internal Medicine. When antibiotics are indicated for sinusitis, the Infectious Diseases Society of America (IDSA) recommends 5 to 7 days of treatment for patients who have a low risk of antibiotic resistance and a favorable response to initial therapy, the authors noted.
The authors used the 2016 National Disease and Therapeutic Index to identify outpatient visits at which antibiotics were prescribed for sinusitis. They described the index as a "stratified cluster sample of drug therapies that is based on a random sample of US office-based physicians in private practice who report on all patient contacts for 2 randomly selected consecutive workdays."
The study included visits at which physicians (family practice, general practice, geriatrics, internal medicine, pediatrics, and emergency medicine) wrote a new prescription for an oral antibiotic for acute sinusitis in an adult.
The authors classified antibiotics as penicillins (including amoxicillin-clavulanate), tetracyclines, fluoroquinolones, cephalosporins, azithromycin, or other. Azithromycin was looked at separately because of "its unique pharmacokinetic characteristics."
Median course was 10 days
The team estimated that almost 3.7 million visits met the study criteria in 2016. They calculated that the median antibiotic course was 10.0 days and that 69.6% of the prescriptions (95% confidence interval [CI], 63.7% to 75.4%) were for 10 days or longer.
"When azithromycin prescriptions were excluded, 91.5% of antibiotic courses (95% CI, 87.8%-95.2%) were 10 days or longer, 7.6% (95% CI, 4.1%-11.1%) were 7 days, and 0.5% (95% CI, 0.0%-1.6%) were 5 days," the report states.
A limitation of the study is that it did not assess underlying conditions or other reasons for longer courses of antibiotics, the authors noted.
They comment that the IDSA recommends 7- to 10-day antibiotic courses for patients who are at high risk or have had initial treatment failure, but "it is unlikely that such cases represent most patients in our study. Earlier work has shown that 90% of patients with sinusitis that is treated with antibiotics do not require additional antibiotic therapy."
Azithromycin use discouraged
Further, the team said more than 20% of prescriptions were for 5-day courses of azithromycin, even though the IDSA specifically advises against using the drug to treat sinusitis because of its known association with the development of resistance. In addition, because of the way azithromycin persists in tissue, 5 days of treatment is about equivalent to 10 days of treatment with erythromycin, the authors observed.
"The durations of most courses of antibiotic therapy for adult outpatients with sinusitis exceed guideline recommendations, which represents an opportunity to reduce the unnecessary use of antibiotics when therapy with antibiotics is indicated," the report concludes.
Mar 26 JAMA Intern Med abstract
Mar 26 JAMA Intern Med press release