Background: Antibiotics are most frequently prescribed for acute respiratory illnesses (ARI), including influenza and other viral infections for which they are not indicated. This study characterized outpatient antibiotic use for ARI, including the use of broad-spectrum agents most likely to lead to the development of antibiotic resistance and among those with laboratory-confirmed influenza.
Methods: We analyzed data from five sites in the US Influenza Vaccine Effectiveness Network during the 2013–14 influenza season. Outpatients aged ≥6 months with ARI defined by cough of ≤7 days were tested for influenza by RT-PCR for study purposes only. Oral antibioitic prescriptions, medical history, and the first four ICD9 diagnostic codes listed were collected by medical and pharmacy records. Antibiotics were categorized as narrow- or broad-spectrum; the latter included broad-spectrum penicillins, 2nd- to 4th-generation cephalosporins, macrolides, quinolones, and clindamycin.
Results: Of 6004 enrolled patients, 42% (n=2533) were prescribed an antibiotic. Of these, over half (n=1479, 58%) were prescribed a broad-spectrum antibiotic, with the highest proportion among adults ≥50 years (Figure a). Forty-six percent (n=1172) of patients prescribed an antibiotic had a code for which antibiotics are potentially indicated, including sinusitis (n=386, 33%), otitis media (n=364, 31%) and pharyngitis (n=357, 30%). Over half (n=1361, 54%) of patients prescribed antibiotics had diagnostic codes for which antibiotics are rarely or never indicated; 430 (32%) were diagnosed with cough, 363 (27%) with bronchitis (acute and NOS) and 293 (22%) with acute upper respiratory infection. Of 1233 (21%) with PCR-confirmed influenza, 387 (31%) received a prescription (Figure b), comprising 15% of all who received a prescription.
Conclusion: Most ARI patients prescribed an antibiotic were not diagnosed with a condition for which antibiotic treatment is indicated, and the majority of antibiotics prescribed were broad-spectrum. Patients with laboratory-confirmed influenza comprise a substantial proportion of those prescribed antibiotics for ARI symptoms during influenza season. Antibiotic stewardship in ambulatory care settings is urgently needed to improve healthcare quality and reduce unnecessary adverse events and the spread of antibiotic resistance.
J. Clippard, None
M. Gaglani, MedImmune: Investigator , Research support
R. K. Zimmerman, Merck & Co.: Grant Investigator , Research grant
Pfizer: Grant Investigator , Research grant
Sanofi Pasteur: Grant Investigator , Research grant
M. L. Jackson, None
J. G. Petrie, None
H. Q. Mclean, MedImmune: Investigator , Research support
M. P. Nowalk, Pfizer Inc.: Grant Investigator , Research grant
A. Monto, None
E. Belongia, Medimmune: Investigator , Research support
H. Eng, None
B. Flannery, None
A. M. Fry, None