Predictors of antibiotic prescribing for nonspecific upper respiratory infections, acute bronchitis, and acute sinusitis. An UPRNet study. Upper Peninsula Research Network.

BACKGROUND: Antibiotics are often prescribed for viral respiratory infections. The goal of our study was to determine the factors associated with antibiotic prescribing for acute respiratory infections in primary care.
METHODS: We performed an observational study in 15 primary care practices in Michigan using patient and physician surveys distributed during visits for acute respiratory infections. We included patients 4 years or older presenting with symptoms of an acute respiratory infection (n=482). The main outcome measures were prescriptions of antibiotics, signs and symptoms associated with antibiotic prescribing, and clinician-reported reasons for prescribing an antibiotic.
RESULTS: We found that patients who were older than 18 years, sick for more than 14 days, and seen in urgent care clinics were more likely to receive antibiotics. Patients expected antibiotics if they perceived that the drug had helped with similar symptoms in the past. In an adjusted model, the variables significantly associated with antibiotic prescribing were physical findings of sinus tenderness (odds ratio [OR]=20.0; 95% confidence interval [CI], 8.3-43.2), rales/rhonchi (OR=19.9; 95% CI, 9.2-43.2), discolored nasal discharge (OR=11.7; 95% CI, 4.3-31.7), and postnasal drainage (OR=3.1; 95% CI, 1.6-6.0). The presence of clear nasal discharge on examination was negatively associated (OR=0.3; 95% CI, 0.2-0.5).
CONCLUSIONS: Several physical signs play an important role in clinicians' decisions to prescribe antibiotics for respiratory infections. This information will be useful in designing interventions to decrease inappropriate antibiotic prescribing for upper respiratory infections.