Healthcare-associated infections (HAIs) are recognized as one of the most important preventable patient safety events in the inpatient setting, yet previous estimates of the overall burden of HAIs have been limited in their scope and data availability. To remedy this, we generated estimates of the annual burden of HAIs due to Clostridium difficile, methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant (MDR) Pseudomonas aeruginosa, MDR Acinetobacter, MDR Enterobacteriaceae, and vancomycin-resistant Enterococci (VRE) using data from systematic reviews of published studies as well as inputs generated from electronic data from the US Department of Veterans Affairs.
We created a decision analytic simulation model parameterized with estimates of excess length of stay (LOS), readmissions, and mortality attributable to hospital-onset HAIs for our pathogens of interest. To calculate the cost of an HAI, we multiplied the excess LOS and readmission days by the cost per inpatient day from the payer perspective ($2,877). We ran our model using 1,000 1st order and 10,000 2nd order Monte Carlo simulations. We used the incidence rate of each of these HAIs to generate cumulative incidence, cost, and mortality associated with these infections for the US adult population. The model was run separately for each pathogen. Costs were expressed in 2016 US dollars.
Our estimates of the cost (95% CI) per HAI ranged from $39,787 ($20,813-$64,140) for MDR Acinetobacter to $3,384 ($885-$7,717) for VRE. Of the 221,737 (154,615-342,607) annual HAIs estimated by our model, 122,795 (99,087-219,006) were due to Clostridium difficile and 35,484 (27,655-43,313) were due to MRSA. Clostridium difficile and MRSA were also the largest contributors to infection-related deaths. Finally, our model estimated an annual cost of $4.1 billion due to these HAIs with Clostridium difficile and MRSA contributing $1.9 billion and $1.2 billion, respectively. The results from our analyses can be found in Figures 1-3.
We found that HAIs due to MDR bacteria and Clostridium difficile account for a substantial cost and mortality burden in the US. These results are relevant to understanding the expenditures and lives that could be saved through prevention.
R. E. Nelson,
M. Jones, None
V. W. Stevens, None
K. Khader, None
E. Perencevich, None
M. Rubin, None
M. Samore, None