Impact of old age on patient-report outcomes and cost utility for anterior cervical discectomy and fusion surgery for degenerative spine disease.

Purpose: With growing older population and increasing rates of cervical spinal surgery, it is vital to understand the value of cervical surgery in this population. We set forth to determine the cost utility following anterior cervical decompression and fusion (ACDF) for degenerative disease in older patients.
Methods: Patients undergoing ACDF for degenerative diseases were enrolled into prospective longitudinal registry. Patient-reported outcomes (PROs) were recorded at baseline, 1-year, and 2-year postoperatively. Two-year medical resource utilization, missed work, and health-state values [quality-adjusted life years (QALYs)] were assessed to compute cost per QALY gained. Patients were dichotomized based on age: <65 years (younger) and ≥65 years (older) to compare the cost utility in these age groups.
Results: Total 218 (87%) younger patients and 33 (13%) older patients who underwent ACDF were analyzed. Both the groups demonstrated a significant improvement in PROs 2-year following surgery. The older patients had a lower mean cumulative gain in QALYs compared to younger patients at 1 year (0.141 vs. 0.28, P = 0.05) and 2 years (0.211 vs. 0.424, P = 0.04). There was no significant difference in the mean total 2-year cost between older [$21,041 (95% CI $18,466-$23,616)] and younger [$22,669 (95% CI $$21,259-$24,079)] patients (P = 0.27). Two-year cost per QALY gained in older vs. younger patients was ($99,720/QALYs gained vs. ($53,464/QALYs gained, P = 0.68).
Conclusion: ACDF surgery provided a significant gain in health-state utility in older patients with degenerative cervical pathology, with a mean cumulative 2-year cost per QALY gained of $99,720/QALY. While older patients have a slightly higher cost utility compared to their younger counterparts, surgery in the older cohort does provide a significant improvement in pain, disability, and quality-of-life outcomes.