Parsing the Role of Diabetes as a Risk Factor for Anterior Cervical Discectomy and Fusion: A Propensity-adjusted Analysis of the Quality Outcomes Database

Introduction: There remains a paucity of literature on the impact of diabetes mellitus (DM) on morbidity and mortality among patients undergoing spine surgery. The purpose of the present study was to correlate DM with adverse outcomes for patients receiving anterior cervical discectomy and fusion.

Methods: The cervical spine Quality Outcomes Database (QOD) was queried for patients who underwent single-stage cervical spine surgery with known baseline outcomes meeting inclusion criteria. Patients were substratified into two groups including diabetic or non-diabetic. Patient-reported outcomes for each cohort included mJOA, NRS-AP, NRS-NP, NDI, and EQ-5D. Univariate analysis was performed for 3- and 12-month follow-up visits after surgical intervention. Multivariate analysis leveraged propensity-score adjustment to account for significant imbalances in the dataset at baseline. Significance was defined by p < 0.05, and Cohen’s D coefficient > 0.5.

Results: Of 6,889 patients identified who met the inclusion criteria, 1562 were diabetic and 5327 were non-diabetic. As expected, diabetic patients had a greater prevalence of cardiovascular disease, greater history of peripheral vascular disease, and hypertension. On multivariate analysis, diabetic patients had greater odds of developing a UTI in 30 days post-operatively (OR = 2.39 (1.04 – 6.34), p = 0.04). At 3 months, diabetic patients had reduced odds of reaching a minimal clinically important difference (MCID) for neck pain. (OR = 0.82 (95% CI: 0.66 – 0.96), p = 0.012). Adjusted for other factors, there were no differences observed in PROs at 12 months.

Conclusion : We sought to quantify the risk-adjusted, isolated impact of diabetes mellitus as a risk factor for patients receiving anterior cervical discectomy and fusion. We show using a large patient registry that diabetes influences short-term risk but does not significantly impact long-term patient outcomes.