1 van Hout D, et al. BMJ Open 2019;9:e028876. doi:10.1136/bmjopen-2018-028876 Open access Cost-effectiveness of selective digestive decontamination (SDD) versus selective oropharyngeal decontamination (SOD) in intensive care units with low levels of antimicrobial resistance: an individual patient data meta-analysis Denise van Hout,  1,2 Nienke L Plantinga, 2,3 Patricia C Bruijning-Verhagen, 1,2,4 Evelien A N Oostdijk, 2,5 Anne Marie G A de Smet, 2,5 G Ardine de Wit, 1,2,6 Marc J M Bonten, 2,3 Cornelis H van Werkhoven 1,2 To cite: van Hout D, Plantinga NL, Bruijning- Verhagen PC, et al. Cost- effectiveness of selective digestive decontamination (SDD) versus selective oropharyngeal decontamination (SOD) in intensive care units with low levels of antimicrobial resistance: an individual patient data meta-analysis. BMJ Open 2019;9:e028876. doi:10.1136/ bmjopen-2018-028876 ► Prepublication history and additional material for this paper are available online. To view these files, please visit the journal online (http://dx.doi. org/10.1136bmjopen-2018- 028876). This work was presented at the 29th European Congress of Clinical Microbiology & Infectious Diseases, Amsterdam, the Netherlands, 13-16 April 2019. Received 29 December 2018 Revised 30 July 2019 Accepted 31 July 2019 For numbered affiliations see end of article. Correspondence to Denise van Hout; D.vanHout-3@umcutrecht.nl Original research © Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ. ABSTRACT Objective To determine the cost-effectiveness of selective digestive decontamination (SDD) as compared to selective oropharyngeal decontamination (SOD) in intensive care units (ICUs) with low levels of antimicrobial resistance. Design Post-hoc analysis of a previously performed individual patient data meta-analysis of two cluster- randomised cross-over trials. Setting 24 ICUs in the Netherlands. Participants 12 952 ICU patients who were treated with ≥1 dose of SDD (n=6720) or SOD (n=6232). Interventions SDD versus SOD. Primary and secondary outcome measures The incremental cost-effectiveness ratio (ICER; ie, costs to prevent one in-hospital death) was calculated by comparing differences in direct healthcare costs and in-hospital mortality of patients treated with SDD versus SOD. A willingness-to-pay curve was plotted to reflect the probability of cost-effectiveness of SDD for a range of different values of maximum costs per prevented in- hospital death. Results The ICER resulting from the fixed-effect meta- analysis, adjusted for clustering and differences in baseline characteristics, showed that SDD significantly reduced in-hospital mortality (adjusted absolute risk reduction 0.0195, 95% CI 0.0050 to 0.0338) with no difference in costs (adjusted cost difference €62 in favour of SDD, 95% CI –€1079 to €935). Thus, SDD yielded significantly lower in-hospital mortality and comparable costs as compared with SOD. At a willingness-to-pay value of €33 633 per one prevented in-hospital death, SDD had a probability of 90.0% to be cost-effective as compared with SOD. Conclusion In Dutch ICUs, SDD has a very high probability of cost-effectiveness as compared to SOD. These data support the implementation of SDD in settings with low levels of antimicrobial resistance. INTRODUCTION Patients who are admitted to an intensive care unit (ICU) are prone to acquire noso- comial infections, which increase morbidity and mortality. 1–5 Besides detrimental effects on health status, ICU-acquired infections are also responsible for increased expendi- ture in an already costly healthcare setting, further supporting the importance of optimal prevention. 2 6–8 Selective oropharyn- geal decontamination (SOD) and selective decontamination of the digestive tract (SDD) are two infection prevention strategies that aim to eradicate colonisation with aerobic Gram-negative bacteria, Staphylococcus aureus and yeasts, while leaving the anaerobic flora Strengths and limitations of this study ► This is the largest cost-effectiveness analysis (CEA) comparing selective digestive decontamination (SDD) to the selective oropharyngeal decontamina- tion (SOD) regimen thus far. ► Individual patient data were included of all ran- domised controlled trials that made a head-to- head comparison of SDD versus SOD in intensive care units (ICUs) with low prevalence of antibiotic resistance. ► Statistical analyses were adjusted for clustering within studies and hospitals and for baseline differ- ences between intervention arms. ► This CEA was performed from a healthcare perspec- tive and cost-effectiveness from a societal perspec- tive could not be determined. ► The results of the current study are generalisable to ICU settings with low levels of antimicrobial resistance. on June 1, 2020 by guest. 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