CS3 - Projected Medicare Savings Associated with Lowering the Risk of Total HIP Arthroplasty Revision: An Administrative Claims Database Analysis

Abstract

In the United States (US), incidence of total hip arthroplasty (THA) and THA revision procedures is increasing due to an aging population, longer life expectancy, and increasing prevalence of osteoarthritis (OA). We conducted a retrospective cohort study to estimate the clinical and economic burden of THA revisions in a Medicare population. We identified persons aged ≥65 in the Medicare 5% Standard Analytic Files who underwent THA for OA between January 1, 2009 and September 30, 2010. Defining a revision as ≥1 medical claim for a revision procedure following discharge from the THA hospitalization, we used the Kaplan-Meier method to calculate 5-year cumulative revision risk (CRR) through September 30, 2015. Medicare expenditures were calculated for the revision episode of care (inpatient stay plus 90-day global period for Medicare bundled payment). Using a 6.22% compound annual growth rate from the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality, we estimated the number of THAs to be performed in 2018-2027 and calculated the 10-year projected savings to Medicare for a 1% CRR reduction. Among 7,820 eligible patients, mean age was 74.4 years, with 62.4% female. CRR was 4.2% at 5 years, with 30.8% of revisions occurring within 90 days of the THA. At least 25% of revision patients had a complication. Mean (median) episode-of-care expenditures were $39,274 ($36,157). Conservatively (using median episode-of-care expenditures), if it were to achieve a 1% absolute CRR reduction, Medicare could realize savings of $697 million over 10 years; or $985 million when including Medicare Advantage, which represented 29.2% of 2016 Medicare payments. Strategies to reduce the risk of THA revision – such as the use of implant constructs with lower CRR and value-based payment models – are needed to achieve Medicare payment reductions while maintaining or improving quality of care for Medicare beneficiaries.