Prevalence of Clinical Signs Within Reference Ranges Among Hospitalized Patients Prescribed Antibiotics for Pneumonia

This cohort study examines the prescribing rates and duration of antibiotic therapy in patients with possible pneumonia whose clinical signs are within the reference ranges. Importance Antibiotics are frequently prescribed for suspected pneumonia, but overdiagnosis is common and fixed regimens are often used despite randomized trials suggesting it is safe to stop antibiotics once clinical signs are normalizing. Objective To quantify potential excess antibiotic prescribing by characterizing antibiotic use relative to patients' initial clinical signs and subsequent trajectories. Design, Setting, and Participants An observational cohort study was conducted in 2 tertiary and 2 community hospitals in Eastern Massachusetts. All nonventilated adult patients admitted between May 1, 2017, and July 1, 2018 (194 & x202f;521 hospitalizations), were included. Main Outcomes and Measures Identification of all antibiotic starts for possible community-acquired pneumonia (CAP) or hospital-acquired pneumonia (HAP) per clinicians' stated indications. Potential excess antibiotic prescribing was quantified by characterizing the frequency of patients in whom all clinical signs were within reference ranges on the first day of antibiotic therapy and by how long antibiotic therapy was continued after all clinical signs were normal, including postdischarge antibiotics. Results Among 194 & x202f;521 hospitalizations, 9540 patients were treated for possible CAP (4574 [48.0%] women; mean [SD] age, 67.6 [17.0] years) and 2733 for possible HAP (1211 [44.3%] women; mean [SD] age, 66.7 [16.2] years). Temperature, respiratory rate, oxygen saturation, and white blood cell count were all within reference ranges on the first day of antibiotics in 1779 of 9540 (18.6%) episodes of CAP and 370 of 2733 (13.5%) episodes of HAP. Antibiotics were continued for 3 days or longer after all clinical signs were normal in 3322 of 9540 (34.8%) episodes of CAP and 1050 of 2733 (38.4%) episodes of HAP. Up to 24 & x202f;978 of 71 & x202f;706 (34.8%) antibiotic-days prescribed for possible pneumonia may have been unnecessary. Conclusions and Relevance In this study, almost one-fifth of hospitalized patients treated for pneumonia did not have any of the cardinal signs of pneumonia on the first day of treatment and antibiotics were continued for 3 days or longer after all signs were normal in more than a third of patients. These observations suggest substantial opportunities to improve antibiotic prescribing. Question What is the prevalence of antibiotic therapy for possible pneumonia in hospitalized patients despite clinical signs within the reference range? Findings In this cohort study of 12 & x202f;273 patients treated for possible pneumonia in 4 hospitals, all cardinal signs for pneumonia were within reference ranges in 18.6% of patients with possible community-acquired pneumonia and 13.5% of patients with possible hospital-acquired pneumonia. Antibiotics were continued for 3 days or longer after all clinical signs were normal in 34.8% of patients treated for community-acquired pneumonia and 38.4% treated for hospital-acquired pneumonia. Meaning Findings of this study suggest that antibiotics are prescribed frequently for suspected pneumonia in patients with clinical signs within reference ranges and continued for 3 days or longer after clinical signs normalize; these findings suggest potential targets to improve prescribing.