Comparing Medicare and Non-Medicare Inpatient Total Hip Arthroplasty: Is the New Centers for Medicare and Medicaid Services Patient-Reported Outcomes Performance Measure Mandate Applicable to All?

Abstract

The Centers for Medicare & Medicaid Services (CMS) implemented the Patient Reported Outcomes Performance Measure (PRO-PM) policy, mandating reporting of patient-reported outcome measures (PROMs) for total hip arthroplasty (THA). A 22-point improvement in Hip disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS-JR) defines substantial clinical benefit (SCB). However, it remains unclear whether SCB achievement differs across insurance groups. We analyzed a prospectively collected cohort of 3,240 THA patients (2016 to 2023) stratified by insurance: Medicare (n = 2,108), Commercial (n = 921), and Medicaid (n = 211). Baseline demographics, comorbidities, and PROMs were compared between Medicare and non-Medicare patients. Multivariable regressions identified predictors of SCB for HOOS-JR. Medicare patients were older (median 72 versus 60 to 61 years, P < 0.001), had lower body mass index (median 29 versus 31 to 31.1, P < 0.001), and greater comorbidity, with over 40% having a Charlson Comorbidity Index (CCI) ≥ 2 compared to less than 23% in non-Medicare patients (P < 0.001). Medicare patients demonstrated less baseline disability than Medicaid, but lower mental health compared to commercial patients. Independent predictors of SCB failure included non-White race (odds ratio (OR) = 1.37, P = 0.028), higher comorbidities (OR = 1.12, P = 0.039), and baseline PROM score above the median (OR = 3.92, P < 0.001). Compared with Medicare, commercial insurance was associated with more than twice the odds of SCB failure (OR = 2.08, P = 0.001), while Medicaid showed no difference (OR = 1.14, P = 0.35). A grouped non-Medicare versus Medicare comparison revealed no difference (OR = 1, P = 0.98). Overall, Medicare patients achieved SCB at rates comparable to or better than non-Medicare patients. These findings highlight the complexity of applying uniform thresholds across insurance groups and underscore the need for refined adjustment.