Methicillin-resistant Staphylococcus aureus prevention strategies in the ICU: a clinical decision analysis*.
OBJECTIVE
ICUs are a major reservoir of methicillin-resistant Staphylococcus aureus. Our aim was to estimate costs and effectiveness of methicillin-resistant Staphylococcus aureus prevention policies.


METHODS
We evaluated three up-to-date methicillin-resistant Staphylococcus aureus prevention policies, namely, 1) nasal screening and contact precautions of methicillin-resistant Staphylococcus aureus-positive patients; 2) nasal screening, contact precautions, and decolonization (targeted decolonization) of methicillin-resistant Staphylococcus aureus carriers; and 3) universal decolonization without screening. We implemented a decision-analytic model with deterministic and probabilistic analyses. Methicillin-resistant Staphylococcus aureus infections averted, quality-adjusted life years gained, and incremental cost-effectiveness ratios were calculated. Cost-effectiveness planes and acceptability curves were plotted for various willingness-to-pay thresholds to address uncertainty.


RESULTS
At base-case scenario, universal decolonization was the dominant strategy; it averted 1.31% and 1.59% of methicillin-resistant Staphylococcus aureus infections over targeted decolonization and screening and contact precautions, respectively, and saved $16,203/quality-adjusted life year over targeted decolonization and 14,562/quality-adjusted life year over screening and contact precautions. Results were robust in sensitivity analysis for a wide range of input variables. In probabilistic analysis, universal decolonization increased quality-adjusted life years by 1.06% (95% CI, 1.02-1.09) over targeted decolonization and by 1.29% (95% CI, 1.24-1.33) over screening and contact precautions; universal decolonization resulted in average savings of $172 (95% CI, $168-$175) and $189 (95% CI, $185-$193) over targeted decolonization and screening and contact precautions, respectively. With willingness-to-pay threshold per quality-adjusted life year gained ranging from $0 to $50,000, universal decolonization was dominant over targeted decolonization in 67.5-75.4% and dominant over screening and contact precautions in 66.0-75.4%.


CONCLUSIONS
In the ICU setting, universal decolonization outperforms the other two strategies and is likely to be cost-effective even at low willingness-to-pay thresholds. Assuming 700 annual ICU admissions in an average 12-bed ICU, the projected annual savings reach $129,500 to $135,100.
1Infectious Diseases Division, Rhode Island Hospital, Providence, RI. 2Warren Alpert Medical School of Brown University, Providence, RI.
Panayiotis D
PD
Ziakas
Ioannis M
IM
Zacharioudakis
Fainareti N
FN
Zervou
Eleftherios
E
Mylonakis
D002353:Carrier State / Q000175:diagnosis; D003362:Cost-Benefit Analysis; D003428:Cross Infection / Q000517:prevention & control; D003663:Decision Trees; D006801:Humans; D017053:Infection Control / Q000191:economics* / Q000379:methods*; D007362:Intensive Care Units; D055624:Methicillin-Resistant Staphylococcus aureus; D018803:Models, Economic; D019057:Quality-Adjusted Life Years; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000517:prevention & control*