Antiviral and antibiotic prescribing for influenza in primary care.
BACKGROUND
Anti-influenza antiviral medications reduce influenza-related morbidity, but may often be used inappropriately.


OBJECTIVE
To measure the rate of antiviral and antibiotic prescribing, the appropriateness of antiviral prescribing, and evaluate independent predictors of antiviral and antibiotic prescribing for influenza in primary care.


METHODS
Retrospective analysis of 958 visits of clinician-diagnosed influenza in 21 primary care clinics in eastern Massachusetts from 1999 to 2007. We considered antiviral prescribing appropriate if patients had symptoms for 2 or fewer days, had fever, and any 2 of headache, sore throat, cough, or myalgias.


RESULTS
Clinicians prescribed antivirals in 557 (58%) visits and antibiotics in 104 visits (11%). Of antiviral prescriptions, 38% were not appropriate, most commonly because of symptoms for more than 2 days (24% of antiviral prescriptions). In multivariate modeling, selected independent predictors of antiviral prescribing were symptom duration of 2 or fewer days (odds ratio [OR], 12.4; 95% confidence interval [CI], 8.3 to 18.6), year (OR, 1.4 for each successive influenza season; 95% CI, 1.3 to 1.7), patient age (OR, 1.3 per decade; 95% CI, 1.2 to 1.5), and, compared to having no influenza testing, having a negative influenza test (OR, 5.5; 95% CI, 3.4 to 9.1) or a positive influenza test (OR, 11.4; 95% CI, 6.7 to 19.3). Independent predictors of antibiotic prescribing included otoscopic abnormalities (OR, 3.3; 95% CI, 1.8 to 6.0), abnormal lung examination (OR, 4.0; 95% CI, 2.1 to 6.2), and having a chest x-ray performed (OR, 2.2; 95% CI, 1.3 to 3.8).


CONCLUSIONS
Primary care clinicians are much more likely to prescribe antivirals to patients with symptoms for 2 or fewer days, but also commonly prescribe antivirals inappropriately.
Linder
Jeffrey A
JA
Division of General Medicine and Primary Care, Brigham and Women's Hospital, 1620 Tremont Street, BC-3-2X, Boston, MA 02120, USA. jlinder@partners.org
Nieva
Harry Reyes
HR
Blumentals
William A
WA
D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D000998:Antiviral Agents / Q000627:therapeutic use*; D002648:Child; D005260:Female; D006801:Humans; D007251:Influenza, Human / Q000188:drug therapy*; D008297:Male; D008404:Massachusetts; D055656:Prescriptions; D011320:Primary Health Care; D012189:Retrospective Studies
D000900:Anti-Bacterial Agents; D000998:Antiviral Agents