The impact of a stewardship program on antibiotic administration in community-acquired pneumonia: results from an observational before-after study

BACKGROUND: A majority of patients with community-acquired pneumonia (CAP) receive antibiotics. According to the evidence, 5-7 days of treatment should be sufficient for most patients. Many, however, are treated longer than recommended. We have previously conducted a quality improvement study to ensure guideline-conform treatment for CAP. However, the impact of the interventions on antibiotic use has not been investigated.

OBJECTIVE: To estimate the impact of an eight-month stewardship program on antibiotic use.

METHODS: We conducted a before-after study comparing a four-month baseline period with data from a corresponding follow-up period. We performed univariable and multivariable logistic regression to compare odds for ≤7 days of total antibiotic treatment, ≤3 days of intravenous treatment and the proportion of correct empiric antibiotics. As sensitivity analysis, we repeated the univariable logistic regression on a propensity score-matched cohort by using the same variables we used for adjustments in the multivariable analysis. We also performed subgroup analyses for patients stable ≤72 h of admission.

RESULTS: In total, 771 patients were included. Compared to preintervention, the unadjusted odds ratio (OR) for ≤7 days of total antibiotic treatment were 1.84 (95% CI 1.34-2.54) for the whole population and 2.08 (1.41-3.10) for the stable patients. The OR for ≤3 days of intravenous antibiotics were 1.16 (0.87-1.54) and 1.38 (0.87-2.22), respectively. The OR for correct empiric antibiotics were 1.96 (1.45-2.68) and 1.82 (1.23-2.69). Comparable results regarding all outcomes were derived from the other analyses.

CONCLUSION: The programme resulted in a significantly lower overall antibiotic exposure and a higher proportion of patients treated with the recommended antibiotics without a the reduction of exposure to intravenous antibiotics significantly.