# The mFI-11 frailty index as a predictor of surgical outcomes in elderly patients with brain metastases

## TL;DR

This study shows that frailty, measured by the mFI-11, correlates with worse outcomes in elderly patients undergoing brain metastasis surgery, but functional health (KPS) is a stronger predictor of survival and recovery.

## Contribution

The study demonstrates that functional health (KPS) is a stronger predictor than frailty indices for outcomes in elderly brain metastasis surgery patients.

## Key findings

- Frailty correlated with poorer survival and functional outcomes in elderly brain metastasis surgery patients.
- KPS was the strongest predictor of survival and functional outcomes in multivariate analysis.
- Frailty was not independently predictive of survival or complications in multivariate analysis.

## Abstract

The vulnerability towards disease but also treatment in elderly patients has been referred to as frailty and can be measured using frailty indices, which assess functional health and comorbidities. Frailty has been shown to correlate with survival and functional outcomes in brain tumor patients.

Does frailty, assessed by the 11-item modified Frailty Index (mFI-11), provide useful prognostic information in elderly patients undergoing brain metastasis surgery?

A retrospective analysis of 139 patients aged ≥60 years who underwent brain metastasis resection (2015–2019) was conducted. Frailty was assessed using the mFI-11.

Increasing frailty correlated with poorer median overall survival (mFI 0: 13.8 months [95 %-CI: 8.7–18.9] vs. mFI 1–2l: 8.7 [5.8–11.6] vs. mFI≥3: 2.8 [0.9–4.6], p = 0.001) and functional outcome (postoperative KPS 80–100 %, mFI 0: 27/36 [75.0 %] vs. mFI 1–2: 44/64 [68.8 %] vs. mFI≥3: 13/38 [34.2 %], p < 0.001). Age was less prognostic. In the multivariate analyses, mFI-11 and age were not independently predictive, while KPS was. Frailty was not associated with major complications.

While frailty correlates with outcome, functional health rather than comorbidities and age is prognostic. The mFI-11's predictive ability may be largely due to its inclusion of a functional health assessment.

Functional health (KPS) is a much stronger predictor of survival and functional outcome in the elderly than the presence of comorbidities and age, i.e. age per se and comorbidities without impact on the patient's functional health status (i.e. well-treated) should not deter from surgery. Frailty is not a predictor of complications.

•Frailty correlated with poorer outcomes in elderly undergoing brain metastases surgery.•Preoperative KPS was the strongest predictor of survival and functional outcome.•mFI was not prognostic for survival or functional outcome in multivariate analysis.•Retrospective analysis of 139 patients ≥60 years with resected brain metastases.

Frailty correlated with poorer outcomes in elderly undergoing brain metastases surgery.

Preoperative KPS was the strongest predictor of survival and functional outcome.

mFI was not prognostic for survival or functional outcome in multivariate analysis.

Retrospective analysis of 139 patients ≥60 years with resected brain metastases.