Anterior Cervical Discectomy and Fusion in the Ambulatory Surgery Center Versus Inpatient Setting: One-Year Cost-Utility Analysis

Abstract

Study Design. Retrospective analysis of prospectively collected data. Objective. Assess the cost-utility of anterior cervical discectomy and fusion (ACDF) performed in the ambulatory surgery center (ASC) versus inpatient hospital setting for Medicare and privately insured patients at one-year follow-up. Summary of Background Data. Outpatient ACDF has gained popularity due to improved safety and reduced costs. Formal cost-utility studies for ambulatory versus inpatient ACDF are lacking, precluding an accurate assessment of cost-effectiveness. Materials and Methods. A total of 6504 patients enrolled in the Quality Outcomes Database (QOD) undergoing one-level to two-level ACDF at a single ASC (520) or the inpatient hospital setting (5984) were compared. Propensity matching generated 748 patients for analysis (374 per cohort). Demographic data, resource utilization, patient-reported outcome measures, and quality-adjusted life-years (QALYs) were assessed. Direct costs (1-year resource use×unit costs based on Medicare national allowable payment amounts) and indirect costs (missed workdays×average US daily wage) were recorded. Incremental cost-effectiveness ratios were calculated. Results. Complication rates and improvements in patient-reported outcome measures and QALYs were similar between groups. Ambulatory ACDF was associated with significantly lower total costs at 1 year for Medicare ($5879.46) and privately insured ($12,873.97) patients, respectively. The incremental cost-effectiveness ratios for inpatient ACDF was $3,674,662 and $8,046,231 for Medicare and privately insured patients, respectively, reflecting unacceptably poor cost-utility. Conclusion. Inpatient ACDF is associated with significant increases in total costs compared to the ASC setting without a safety, outcome, or QALY benefit. The ASC setting is a dominant option from a health economy perspective for first-time one-l to two-level ACDF in select patients compared to the inpatient hospital setting.