Oncology patients are prone to frailty, described as a lack of physiological reserve and greater vulnerability to physiological stress. Given the palliative nature of spine metastasis surgery, patients must be in good enough health to withstand the physical trauma of the procedure. For this study, the researchers compared the relationship between two frailty measures and the widely used Charlson Comorbidity Index (CCI) and postoperative morbidity in patients with spine metastases. 

A retrospective cohort of patients with spinal metastases who underwent surgeries at a comprehensive cancer center was found. The researchers gathered information on the patient’s demographics, illness state, medical comorbidities, operation details, and postoperative results. They used the modified 5-item frailty index (mFI-5) and the metastatic spinal tumor frailty index to assess frailty (MSTFI). The researchers were looking for the length of stay (LOS) larger than the cohort’s 75th percentile, nonroutine discharge, and the occurrence of ≥ 1 postoperative complication.

A total of 322 individuals (mean age 59.5 ± 12 years; 56.9% of patients were male) were included in the study. The mean ± SD LOS was 11.2 ± 9.9 days, 44.5% of patients were discharged non routinely, and 24.0% experienced ≥ 1 postoperative complication. Increased frailty on the mFI-5 and MSTFI was independently predictive of all three outcomes on multivariable analysis: prolonged LOS (OR 1.67 per point, 95% CI 1.06–2.63, p = 0.03; and OR 1.63 per point, 95% CI 1.29–2.05, p < 0.01, respectively), nonroutine discharge (OR 2.65 per point, 95% CI 1.74–4.04, p <  0.01; and OR 1.69 per point, 95% CI1.12–1.77, p < 0.01). Only one postoperative complication was observed to be independently predictive of CCI (OR 1.45 per point, 95% CI 1.22–1.72, p < 0.01).

As measured by the mFI-5 or MSTFI scores, frailty was a more reliable independent predictor of poor postoperative outcomes than the more commonly used CCI. Longer LOS, greater complication rates, and nonroutine discharge were related to mFI-5 and MSTFI. It is necessary to conduct more research in a prospective multicenter cohort.