Does Dual-Eligible Medicare/Medicaid Insurance Status as a Surrogate for Socioeconomic Status Compromise Total Knee Arthroplasty Outcomes?

Abstract

Background: Medicare/Medicaid dual-eligible patients who undergo primary total knee arthroplasty (TKA) demonstrate poor outcomes when compared to patients with other payers. We compare Medicare/Medicaid dual-eligible patients vs Medicare and Medicaid only patients at a single hospital center.

Methods: All patients who underwent TKA for aseptic arthritis between August 9, 2016 and December 30, 2020 with either Medicare or Medicaid insurance were retrospectively reviewed. 4599 consecutive TKA (3749 Medicare, 286 Medicare/Medicaid dual eligibility, and 564 Medicaid) were included. Groups were compared using appropriate tests for direct comparisons and regression analysis.

Results: Patients with dual eligibility and Medicaid insurance were less likely to be white and married, more likely to be female and current smokers, and more likely to have COPD, mild liver disease, diabetes mellitus, malignancy, and HIV/AIDS, but had a lower age-adjusted Charleson Comorbidity Index when compared to Medicare patients. When controlling for smoking status and medical comorbidities, patients with dual eligibility and Medicaid insurance stayed in the hospital 0.64 and 0.39 additional days (P < .001), respectively, were more likely to be discharged to subacute rehab (RR 2.01, 1.49, P < .001) and acute rehab (RR 2.22, 2.46, P = .007, < .001), and were 2.14 and 1.73 times more likely to return to the ED within 90 days (P < .001) compared to Medicare patients.

Conclusion: Value-based healthcare may disincentivize treating patients with low socioeconomic status, represented by Medicaid and dual-eligible insurance status, by their association with increased postoperative healthcare utilization, and less risky patients may be prioritized.

Keywords: access to care; arthroplasty; insurance; knee replacement; socioeconomic status; value-based healthcare.