Outpatient Antimicrobial Stewardship: Targets for Community-acquired Pneumonia

Purpose

Community-acquired pneumonia (CAP) is one of the leading causes of death in the United States. The primary objective of this study was to determine the prevalence of appropriate diagnosis and treatment of outpatients treated for CAP. Knowledge of problems with CAP treatment can be helpful in developing stewardship initiatives to improve care of outpatients with CAP.

Methods

Included in this study were patients 18 years and older who received antibiotic therapy for the treatment of CAP in the outpatient setting. Outpatients were identified by International Classification of Diseases, Ninth Revision (ICD-9) and International Classification of Diseases, Tenth Revision (ICD-10) codes for CAP in the Veterans Affairs Western New York Healthcare System between January 2008 and January 2018. Appropriate treatment was evaluated using CAP guidelines. Factors associated with an inappropriate regimen were determined via multivariable analyses.

Findings

This study included 518 outpatients, of whom 66% were appropriately diagnosed with CAP. Of the 341 appropriately diagnosed patients, only 31% received an antibiotic regimen consistent with guidelines. Regarding inappropriate regimens, 76.7% contained an incorrect drug based on patient comorbidities, and 39.4% consisted of an inappropriate duration, which was most often attributable to prolonged length of therapy >7 days. The odds of being prescribed an inappropriate regimen if a patient was considered to be at risk for drug-resistant Streptococcus pneumoniae (DRSP) was 4.2 (95% CI, 2.4–7.4). The population at risk for DRSP was more likely to present to the health care system again within 30 days compared with low-risk patients (19.4% vs 8.7%, P = 0.005).

Implications

Improvement in prescribing is needed for CAP. An outpatient stewardship program that targets patients with risk factors for DRSP would improve adherence to guidelines.