Appropriateness of antibiotic prescribing in veterans with community-acquired pneumonia, sinusitis, or acute exacerbations of chronic bronchitis: a cross-sectional study.

BACKGROUND

Studies that have assessed antibiotic appropriateness in acute respiratory tract infections (RTIs) with a likely bacterial etiology have focused only on antibiotic choice and ignored other important aspects of prescribing, such as dosing, drug-drug interactions, and duration of treatment.

OBJECTIVE

The aim of this study was to determine the prevalence and predictors of inappropriate antibiotic prescribing practices in outpatients with acute bacterial RTIs (community-acquired pneumonia [CAP], sinusitis, or acute exacerbations of chronic bronchitis [AECB]).

METHODS

This retrospective, cross-sectional study enrolled outpatients with CAP, sinusitis, or AECB who were evaluated in a Veterans Affairs emergency department over a 1-year period. Using electronic medical records, trained research assistants completed data-collection forms that included patient characteristics (eg, marital status, history of alcohol abuse), diagnosis, comorbidities, concurrent medications, and antibiotics prescribed. To assess antimicrobial appropriateness, a trained clinical pharmacist reviewed the data-collection forms and applied a Medication Appropriateness Index (MAI), which rated the appropriateness of a medication using 10 criteria: indication, effectiveness, dosage, directions, practicality (defined as capability of being used or being put into practice), drug-drug interactions, drug-disease interactions, unnecessary duplication, duration, and expensiveness (defined as the cost of the drug compared with other agents of similar efficacy and tolerability). Previous studies have found good inter- and intrarater reliabilities between a clinical pharmacist's and an internal medicine physician's MAI ratings (kappa=0.83 and 0.92, respectively).

RESULTS

One hundred fifty-three patients were included (mean age, 58 years; 92% male; and 65% white). Overall, 99 of 153 patients (65%) had inappropriate antibiotic prescribing as assessed using the MAI. Expensiveness (60 patients [39%]), impracticality (32 [21%]), and incorrect dosage (15 [10%]) were the most frequently rated problem. Penicillins, quinolones, and macrolides were the most common antibiotic classes prescribed inappropriately. A history of alcohol abuse was associated with a lower likelihood of inappropriate prescribing compared with no history of alcohol abuse (adjusted odds ratio [AOR], 0.32; 95% CI, 0.10-0.98), while patients who were married were more likely to receive inappropriately prescribed antibiotics than those who were not married (AOR, 2.64; 95% CI, 1.25-5.59).

CONCLUSIONS

Inappropriate antibiotic prescribing based on the MAI criteria was common (65%) in this selected patient population with acute bacterial RTIs, and often involved problems with expensiveness (39%), impracticality (21%), and incorrect dosage (10%). Future interventions to improve antibiotic prescribing should consider aspects beyond choice of agent.