(SS#II) Increasing Frailty Is Negatively Correlated with Long Term Functional Outcomes After Surgery for Degenerative Cervical Myelopathy; 757 Patients from the CSM-NA and CSM-I Observational Studies

Introduction: Frailty assessment is increasingly of relevance compared to age alone when evaluating patients with degenerative spine disease. The effect of frailty on the long-term outcomes after surgery for degenerative cervical myelopathy (DCM) patients has not been reported. The objective of the current study was to define the effect of frailty on the functional and quality of life outcomes on surgical DCM patients.

Methods: Patients enrolled to the CSM-International and CSM-North America multi-center, prospective cohort studies underwent functional (MJOA scale) and quality of life (SF-36 mental and physical component scores [MCS, PCS]) assessments prior to surgery and at 2 year follow up. The modified frailty index 5-point score (MFI-5) was calculated for all patients. “Pre-Frail”, “Frail” and “Severely Frail” were compared to “Not Frail” patients on univariate analysis for all outcome measures, and the odds of achieving the minimum clinical important difference (MCID) for each.

Results: 757 patients were included, with a mean age of 56[55-57] years (37% female). Increasing frailty was associated with increasing age (p < 0.001), worse baseline MJOA score (p < 0.001) and worse baseline PCS and MCS scores (p < 0.001, p=0.001). Frailty did not affect the mean difference of MJOA scores after 2 years (2.43[2.15-2.71] vs 2.6[2.04-3.16]; p=0.605) or the change in PCS/MCS scores (p=0.899, p=0.138). The odds of achieving MCID for the MJOA is significantly reduced with increasing frailty (OR=3.1[2.4-3.9], p< 0.001 for “Not Frail” vs OR=1.1[0.8-1.6]; p=0.5 for “Frail/Severely Frail” patients), but frailty did not affect the odds of achieving MCID for PCS/MCS.

Conclusion : Increasing frailty is associated with worse baseline functional and quality of life impairment for DCM patients, but this does not affect the mean difference in MJOA or PCS/MCS scores after 2 years. Frailty has a significant effect on the odds of achieving the MCID for functional outcomes, but not quality of life outcomes.