Cost-Effectiveness of Universal MRSA Screening on Admission to Surgery

Cost-Effectiveness of Universal MRSA Screening on Admission to Surgery

Background:  This study assessed the cost-effectiveness of universal rapid MRSA screening with PCR on admission to surgery as compared to a strategy involving risk-factor screening or standard surgical admission without screening. 

Objective:   Policy-makers have recommended universal screening on admission to reduce nosocomial MRSA infection.  Risk profiling algorithms and rapid PCR tests are now available and have been evaluated in published literature, yet cost-effectiveness data are limited. Decisions taken by hospital administrators regarding investments in infection control would benefit from economic evaluations.  This study aimed to assess the cost-effectiveness of rapid PCR screening.

Methods:  A decision analytic Markov model from the hospital perspective compared costs and effects of three strategies: (1) rapid PCR screening; (2) screening patients with risk factors (prior hospitalization or antibiotic use) combined with pre-emptive isolation and contact precautions pending chromogenic agar results; (3) no screening. Clinical and epidemiology data were taken from a large well-designed study at the University of Geneva Hospitals as well as published literature.  Costs were derived from hospital accounting systems.  Uncertainty in key input variables was explored through sensitivity and threshold analyses. 

Results: Compared to no screening, the universal PCR strategy resulted in slightly higher costs (CHF 10,358 vs. 10,503) but fewer infections (.009 vs. .004) in the decision model, producing an incremental cost-effectiveness ratio (ICER) of CHF 30,769 per infection avoided. The risk factor strategy was both more costly and less effective than PCR, although after varying key epidemiologic inputs the costs and effects of both screening strategies were similar relative to no screening. Sensitivity analyses suggested that prevalence of MRSA carriage on admission predicts cost-effectiveness (figure), along with the probability of cross-transmission (a surrogate for the efficacy of standard efficacy control measures), the costs of MRSA infection, screening costs, and contact precaution costs.  Higher rates of cross-transmission, higher on-admission prevalence and higher costs per MRSA infection improve the cost-effectiveness of universal screening as the benefits of early detection are greater.  In contrast, lower rates of cross-transmission, and higher costs for screening and infection control measures worsened the cost-effectiveness of rapid PCR.  

Conclusions: Compared to risk profiling with pre-emptive isolation, universal screening is not strongly cost-effective at our center. However, local epidemiology plays a critical role. Settings with higher prevalence of MRSA colonization may find universal screening cost-effective and in some cases potentially cost-saving.