An evaluation of the impact of antibiotic stewardship on reducing the use of high-risk antibiotics and its effect on the incidence of Clostridium difficile infection in hospital settings

Mamoon A. Aldeyab, Mary P. Kearney, Michael G. Scott, Motasem A. Aldiab, Yaser M. Alahmadi, Feras W. Darwish Elhajji, Fidelma A. Magee, James C. McElnay

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86 Citations (Scopus)


Objectives: To evaluate the impact of a high-risk antibiotic stewardship programme on reducing antibiotic use and on hospital Clostridium difficile infection (CDI) incidence rates. A secondary objective was to present the possible utility of time-series analysis as an antibiotic risk classification tool. Methods: This was an interventional, retrospective, ecological investigation in a medium-sized hospital over 6.5 years (January 2004 to June 2010). The intervention was the restriction of high-risk antibiotics (second-generation cephalosporins, third-generation cephalosporins, fluoroquinolones and clindamycin). Amoxicillin/clavulanic acid and macrolides were classified as medium-risk antibiotics based on time-series analysis findings and their use was monitored. The intervention was evaluated by segmented regression analysis of interrupted time series. Results: The intervention was associated with a significant change in level of use of high-risk antibiotics (coefficient -17.3, P< 0.0001) and with a borderline significant trend change in their use being reduced by 0.156 defined daily doses/100 bed-days per month (P=0.0597). The reduction in the use of high-risk antibiotics was associated with a significant change in the incidence trend of CDI (P=0.0081), i.e. the CDI incidence rate decreased by 0.0047/100 bed-days per month. Analysis showed that variations in the incidence of CDI were affected by the age-adjusted comorbidity index with a lag of 1 month (coefficient 0.137051, P=0.0182). Significant decreases in slope (coefficient -0.414, P=.0309) post-intervention were also observed for the monitored medium-risk antibiotics. Conclusions: The restriction of the high-risk antibiotics contributed to both a reduction in their use and a reduction in the incidence of CDI in the study site hospital. Time-series analysis can be utilized as a risk classification tool with utility in antibiotic stewardship design and quality improvement programmes.

Original languageEnglish
Article numberdks330
Pages (from-to)2988-2996
Number of pages9
JournalJournal of Antimicrobial Chemotherapy
Issue number12
Early online date16 Aug 2012
Publication statusPublished - Dec 2012
Externally publishedYes


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