Does Age and Medicare Status Affect Clinical Outcomes in Patients Undergoing Anterior Cervical Discectomy and Fusion?

Abstract

The objective of this study was to determine if Medicare status and age affect clinical outcomes following anterior cervical discectomy and fusion. Patients who underwent cervical discectomy and fusion between 2014 and 2020 with complete preoperative and 1-year postoperative patient-reported outcome measures (PROMs) were grouped based on Medicare status and age: no Medicare under 65years (NM<65), Medicare under 65years (M < 65), no Medicare 65years or older (NM≥65), and Medicare 65years or older (M ≥ 65). Multivariate regression for ΔPROMs (Δ: postoperative minus preoperative) controlled for confounding differences between groups. Significant was set at P < 0.05. A total of 1288 patients were included, with each group improving in the visual analog score (VAS) Neck (all, P < 0.001), VAS Arm (M < 65: P= 0.003; remaining groups: P < 0.001), and Neck Disability Index (M < 65: P= 0.009; remaining groups: P < 0.001) following surgery. Only M < 65 did not significantly improve in the Physical Component Score (PCS-12) and modified Japanese Orthopaedic Association (mJOA) score (P= 0.256 and P= 0.092, respectively). When comparing patients under 65years, non-Medicare patients had better preoperative PCS-12 (P < 0.001), Neck Disability Index (P<0.001), and modified Japanese Orthopaedic Association (P < 0.001), as well as better postoperative values for all PROMs (P < 0.001), but there were no differences in ΔPROMs. Multivariate analysis identified M < 65 to be an independent predictor of decreased improvement in ΔPCS-12 (β=-4.07, P= 0.015), ΔVAS Neck (β= 1.17, P= 0.010), and ΔVAS Arm (β= 1.15, P= 0.025) compared to NM<65. Regardless of age and Medicare status, all patients undergoing cervical discectomy and fusion had significant clinical improvement postoperatively. However, Medicare patients under age 65 have a smaller magnitude of improvement in PROMs.