Overall Duration of Antibiotic Use Among Adults With Community-Acquired Pneumonia Requiring Hospitalization

Abstract

Background. Community-acquired pneumonia (CAP) is a leading indication for antibiotic use, but studies suggest prolonged therapy durations may not improve outcome. IDSA/ATS guidelines (2007) recommend 5 days minimum therapy for CAP, and suggest durations >5-7 days are rarely necessary. To identify opportunities to improve antibiotic stewardship, we investigated total duration of therapy for US adults hospitalized for CAP. Methods. Using two data sources, total length of therapy (LOT) was estimated for two patient populations discharged from qualifying CAP hospitalizations in 2012: 1) 18-64 years with private insurance in the MarketScan Commercial Claims and Encounters files and 2) >=65 years with traditional Medicare in the 100% Medicare claims and Part D event files. Hospitalizations were limited to those with primary diagnosis of pneumonia; length of stay (LOS) 2-10 days; discharged home with self-care; and no previous hospitalizations within 30 days. LOT was defined as days with >=1 antibiotic. For each group, inpatient LOT was estimated as a function of LOS using the adjusted correlation between LOT and LOS observed in MarketScan Hospital Drug Database. Post-discharge prescriptions filled within -1 to +3 days of discharge were obtained from outpatient files. Estimated inpatient and observed outpatient antibiotic LOTs were combined to estimate total LOT. Results. The median total LOT was 9.7 days (IQR: 7.6-12.5) for those 18-64 years and 9.6 days (IQR: 7.4-11.4) for those >=65 years. The top 3 inpatient antibiotics, regardless of age group, were ceftriaxone (24% of all inpatient days of therapy), azithromycin (24%), and levofloxacin (17%). Post-discharge, oral levofloxacin (37% of outpatient prescriptions) and oral azithromycin (18%) were the top 2 prescriptions in both age groups; ranked third was oral moxifloxacin (10%) in those 18-64 years and oral cefuroxime (9%) in those >=65 years. Conclusion. The median total LOT for CAP was just under 10 days, nearly double current recommendations for clinically stable patients. Better adherence to CAP therapy duration guidelines at hospital discharge is an opportunity for inpatient stewardship programs to substantially reduce antibiotic use.