Universal Screening for Malnutrition Prior to Total Knee Arthroplasty Is Cost-Effective: A Markov Analysis

Patients undergoing total knee arthroplasty (TKA) who have malnutrition possess an increased risk of periprosthetic joint infection (PJI). Although malnutrition screening and intervention may decrease the risk of PJI, it utilizes healthcare resources. To date, no cost-effectiveness analyses have been performed on the screening and treatment of malnutrition prior to TKA. A Markov model projecting lifetime costs and quality-adjusted life years (QALYs) was built to determine the cost-effectiveness of malnutrition screening and intervention for TKA patients from a societal perspective. Costs, health state utilities, and state transition probabilities were obtained from previously published literature, hospital costs at our institution, and expert opinions. Two important assumptions included that 30% of patients would be malnourished and that a malnutrition intervention would be 50% effective. The primary outcome of this study was the incremental cost-effectiveness ratio, with a willingness-to-pay threshold of $100,000 per QALY. One-way and two-way sensitivity analyses were performed to evaluate model parameter assumptions. When using the base case values, universal malnutrition screening and intervention was cost-effective compared to no malnutrition screening or intervention, with an incremental cost-effectiveness ratio of $6,454 per QALY. Universal screening and intervention remained cost-effective, provided the cost of screening remained less than $3,373, the cost of nutritional intervention remained less than $12,042, the prevalence of malnutrition among surgical candidates was higher than 2%, and the risk of PJI among patients with malnutrition was greater than 1%. Universal preoperative malnutrition screening and intervention among TKA candidates is cost-effective at parameters encountered in clinical practice. Nutritional optimization programs should be considered to facilitate malnutrition screening and intervention and future studies should evaluate their efficacy at lowering PJI risk.