Prolonged antibiotic treatment durations for community-onset infections in Dutch hospitals.

Background: Antibiotic stewardship programs (ASPs) aim to optimize antibiotic prescribing, as prolonged use increases the risk of adverse events, antimicrobial resistance, and unnecessary healthcare costs. This study aimed to determine the period prevalence of prolonged antibiotic treatment durations for community-onset infections in Dutch hospitals and to identify risk factors. Methods: A retrospective cohort study was conducted among adults treated for urinary tract infections (UTI), respiratory tract infections (RTI), or skin and soft tissue infections (SSTI) in four Dutch secondary care hospitals from January 1, 2021, to December 31, 2023. Patients were included if they were admitted for ≥12 hours and treated with antibiotics within 48 hours. Antibiotic prescriptions were linked to infectious diagnoses to calculate length of therapy and compared against national guidelines to assess prolonged treatment. Backward stepwise multivariable logistic regression was used to identify risk factors. Results: Of 9,878 admissions, 39.6% had UTIs, 44.9% RTIs, and 15.4% SSTIs. Prolonged antibiotic use was observed in 30%, with the highest proportion in RTIs (49.6%). Among RTIs, prolonged use occurred in 51.0% of community-acquired pneumonia (CAP) and 55.9% of aspiration pneumonia, with a combined median excess duration of 1.6 days (IQR: 0.9-3.6)). Prolonged use was 14.3% in UTIs and 13.1% in SSTIs. Risk factors included positive cultures, intravenous-to-oral switch, aspiration pneumonia or CAP (RTIs), and cystitis (UTIs). Conclusions: A high period prevalence of patients with RTIs receiving prolonged antibiotic treatment was observed. The identified risk factors should be considered in ASPs to improve prescribing and reduce non-guideline-concordant antibiotic therapy.