Longer antibiotic therapy in patients with low procalcitonin during COPD exacerbation increased LOS without reducing readmissions

The retrospective study divided patients by whether they received inpatient antibiotics for more or less than a day, and patients in the former group had a length of stay (LOS) of 3.7 days compared to 2.8 days in the latter.*

More than 24 hours of antibiotic therapy led to longer length of stay (LOS) without improving readmission rates in patients admitted with acute exacerbations of chronic obstructive pulmonary disease (COPD) who had low procalcitonin levels, a recent study found.

Researchers retrospectively evaluated 356 non-critically ill adults admitted with acute exacerbations of COPD who had peak procalcitonin concentrations of less than 0.25 µg/L. They split patients into two groups: those with 24 hours or fewer of antibiotic exposure (n=161) and those with more than 24 hours of antibiotic exposure (n=195). Researchers also assessed two groups of patients who received either 24 hours or fewer of azithromycin therapy or more than 24 hours of exposure to the antibiotic. In both analyses, the primary outcome was all-cause 30-day readmissions, and secondary outcomes included LOS and COPD-related 30-day readmissions. Results were published online on July 2 by Clinical Infectious Diseases.

The mean duration of antibiotic therapy was 5.5 days in the cohort that received more than 24 hours of antibiotic therapy, whereas 67% of patients in the group that received 24 hours or fewer of antibiotic therapy received no doses. The group with 24 hours or fewer of exposure to antibiotics had a shorter LOS than the group with more than 24 hours of exposure (2.8 d vs. 3.7 d; P<0.01). The rates of all-cause 30-day readmissions and COPD-related 30-day readmissions were not significantly different between the respective groups (15.5% vs. 17.4% [P=0.63] and 11.2% vs. 12.3% [P=0.74], respectively).

In the azithromycin subgroup analysis, 51% of patients who received 24 hours or fewer of therapy received no doses. Patients who received azithromycin for 24 hours or fewer had a shorter LOS compared to patients who received the drug for more than 24 hours (3.0 d vs. 3.8 d; P<0.01), and there were no significant differences between the respective groups in the rate of all-cause 30-day readmissions (16.2% vs. 17.1%; P=0.82) or COPD-related 30-day readmissions (11.9% vs. 11.6%; P=0.94).

The study authors noted limitations of the analysis, such as its retrospective nature and their inability to determine if undetected patient-specific factors played a role in the decision to prescribe antibiotic therapy in spite of low procalcitonin levels.

“We believe this study adds significant data to help antimicrobial stewardship programs curb antibiotic misuse for patients with [acute exacerbations of] COPD by utilizing [procalcitonin] as an objective biomarker to refrain from utilizing extended courses of antibiotics in clinically stable patients without elevated [procalcitonin] concentrations,” they concluded.