Can Prior Episode-of-Care Costs Predict the Future? Identifying High-Cost Outliers for Subsequent Total Hip and Knee Arthroplasty

It remains unknown if a patient’s prior episode-of-care (EOC) costs for total hip (THA) or knee (TKA) arthroplasty procedure can be used to predict subsequent costs for future procedures. The purpose of this study is to evaluate whether there is a correlation between the EOC costs for a patient’s index and subsequent THA or TKA.

We reviewed a consecutive series of 11,599 THA and TKA Medicare patients from 2015 to 2019 and identified all patients who underwent a subsequent THA and TKA during the study period. We collected demographics, comorbidities, short-term outcomes, and 90-day EOC claims costs. A multivariate analysis was performed to identify whether prior high-EOC costs were predictive of high costs for the subsequent procedure.

Of the 774 patients (6.7%) who underwent a subsequent THA or TKA, there was no difference in readmissions (4% vs 5%, P = .70), rate of discharge to a skilled nursing facility (SNF) (15% vs 15%, P = .89), and mean costs ($18,534 vs $18,532, P = .99) between EOCs. High-cost patients for the initial TKA or THA were more likely to be high cost for subsequent procedure (odds ratio 14.33, P < .01). Repeat high-cost patients were more likely to discharge to an SNF for their first and second EOC compared to normative-cost patients (P < .01).

High-cost patients for their initial THA or TKA are likely to be high cost for a subsequent procedure, secondary to a high rate of SNF utilization. Efforts to reduce costs in repeat high-cost patients should focus on addressing post-operative needs pre-operatively to facilitate safe discharge home.