Anterior Cervical Discectomy and Fusion in the Ambulatory Surgery Center Versus Inpatient Setting: One-Year Cost-Utility Analysis
Steve H. Monk, Ummey Hani, Deborah Pfortmiller, Mark D. Smith, Paul K. Kim, Michael A. Bohl, Domagoj Coric, Tim E. Adamson, Christopher M. Holland, Matthew J. McGirt
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.