A Comprehensive Assessment of the Influence of Frailty in Patients Undergoing Surgery for Degenerative Cervical Myelopathy

Introduction: To evaluate the impact of frailty on functional status, disability, and quality of life outcomes in patients with degenerative cervical myelopathy (DCM).

Methods: Data from two prospective cohort studies (AO Spine CSM-North America; AO Spine CSM-International) and one randomized controlled trial (CSM-Protect) of DCM were combined. Outcomes included mJOA, NDI, and SF-36 scores. Frailty was assessed using a 30-item DCM-related frailty index (DCM-FI) derived with Searle et al.’s method. Patients were classified as non-frail ( < 0.3) or frail (≥ 0.3) based on DCM-FI. Differences in outcomes between frail and non-frail groups at baseline, 6 months, and 1 year post-operatively were analyzed using adjusted mixed-effects regression. Multivariable linear regression compared frailty and age associations with 1-year outcome changes.

Results: 797 patients met eligibility criteria (mean age 56.6 ± 11.4 years; 37.5% female) of which 230 (28.9%) were non-frail, and 567 (71.1%) were frail. Frail patients had greater impairment, disability, and poorer quality of life at baseline. On adjusted comparison, the frail group showed greater improvements in mJOA (MD 0.59, P< 0.01), NDI (MD -7.43, P< 0.01), SF-36 PCS (MD 3.38, P< 0.01), and SF-36 MCS (MD 34.40, P< 0.01) at 6 months post-surgery but remained more impaired overall, persisting at 1 year. Adjusting for equal baseline scores, frailty was linked to proportionally smaller improvements in mJOA (MD -0.62, P< 0.01), NDI (MD 3.84, P< 0.01), SF-36 PCS (MD -1.78, P=0.02), and SF-36 MCS (MD -1.90, P=0.03) at 6 months, with significant associations for mJOA and SF-36 PCS persisting at 1 year. Frailty was a stronger predictor of changes in mJOA, NDI, SF-36 PCS, and SF-36 MCS at 1 year than age.

Conclusion : Frail patients had larger post-operative improvements in mJOA, NDI, and SF-36 scores, yet their overall outcomes remained worse than non-frail patients at 6 months and 1 year. Adjusting for baseline scores, frailty was independently associated with smaller incremental improvements after surgical decompression and was a stronger predictor of outcomes than age.