The impact of a stewardship programme on outcomes in patients admitted with community-acquired pneumonia

Background: Community-acquired pneumonia (CAP) is a common cause of antibiotic prescription, hospital admission and mortality. Guideline adherence has shown to be beneficial in CAP. However, adherence to recommendations is highly variable. We have previously conducted a quality improvement project to increase guideline adherence. The project itself was a success, but the impact on key outcomes has not been assessed yet. Material and methods To assess the impact of a stewardship programme containing various interventions, we conducted a before-after assessment on a propensity-score matched cohort (PSM). The cohort was matched on age, comorbidities, multiple infiltrates on chest X-ray, CURB-65 score, oxygen saturation at admission, and antibiotics before admission. We then compared the odds for various outcomes in the baseline period (11/2017-2/2018) with the follow-up period (11/2018-2/2019) using logistic regression. Results: The PSM cohort consisted of 345 patients in each period. The odds ratio (OR) for 30-days-mortality was 0.91 (95% CI 0.54-1.50). For patients stable ≤72 hours from admission, the OR for ≤5 days of admission was 1.27 (0.76-2.16). The OR for ≤3 days of intravenous and ≤7 days of total antibiotic therapy were 1.54 (0.95-2.53) and 2.22 (1.45-3.40), respectively. The OR for correct empiric antibiotic therapy was 1.63 (1.08-2.47). Discussion: The stewardship programme lead to an increase in patients treated with the correct antibiotic as well as a higher amount of patients treated ≤7 days. The point estimates for the other outcomes were beneficial as well, but the effect sizes too large to draw any conclusions. All together, the programme lead to a reduced antibiotic exposure in patients admitted with CAP.