1122 Comparable Clinical Outcomes for Patients Insured by Medicaid Versus Private Insurance after Surgery for High Grade Degenerative Lumbar Spondylolisthesis: An Analysis from the Quality Outcomes Database

INTRODUCTION: Existing literature predominately examines long-term, spine specific, patient reported outcomes (PROs) in patients with low-grade spondylolisthesis, with limited emphasis on high-grade spondylolisthesis. Additionally, the impact of insurance, including Medicaid and private, on PROs for high-grade spondylolisthesis remains unclear. METHODS: Patients who underwent surgery for high-grade lumbar spondylolisthesis were selected from the Quality Outcomes Database registry. 24-month PROs, including Oswestry Disability Index (ODI), Numeric rating Scale (NRS) back pain (BP), NRS leg pain (LP), EuroQol-5D (EQ-5D), and North American Spine Society Satisfaction (NASS) were compared using univariate and multivariate analysis. RESULTS: 241 patients undergoing surgery for high-grade lumbar spondylolisthesis (mean age, 60.9 ± 12.5 years and 66.8% female) were enrolled. Insurance types include private (n = 222; 92.1%) and Medicaid (n = 19; 7.9%). The overall 24-month follow-up rate was 86.3%. In univariate analyses, outcomes scores for both insurance types improved for ODI, NRS-BP, NRS-LP, and EQ-5D from baseline. In multivariable analyses, compared to patients with private insurance, Medicaid demonstrated comparable improvements in 24-month ODI (β = -1.4; 95% confidence interval [CI], -8.4 to 5.7; P = 0.7), NRS-BP (β = -0.87; 95% CI, -1.2 to 2.9; P = 0.4), NRS-LP (β = 0.73; 95% CI, -1.5 to 2.9; P = 0.5), and EQ-5D (β = -0.07; 95% CI, -0.25 to 0.10; P = 0.4). Medicaid demonstrated comparable odds for reaching ODI minimal clinically important difference (odds ratio = 0.62; 95% CI, 0.11 to 3.00; P = 0.6). NASS did not differ between insurance types (P = 0.4). CONCLUSIONS: Prior to surgery, Medicaid beneficiaries presented with poorer PROs compared to patients with private insurance. However, Medicaid beneficiaries demonstrated similar improvements in PROs compared to patients with private insurance at 24-months follow-up. After adjusting for potentially confounding variables, Medicaid beneficiaries consistently demonstrated comparable improvements to private insurance in 24-month PROs.