The impact of frailty on patient selection and outcomes for open versus endovascular treatment of unruptured intracranial aneurysms: A propensity-score matched analysis

Background and Objectives

Endovascular treatment (EVT) has been demonstrated to have improved post-operative outcomes and fewer complications compared to open microsurgical clipping of unruptured intracranial aneurysms (UIAs). Our study analyzes patient selection and outcomes for open versus EVT stratified by frailty measured using the Risk Analysis Index (RAI).

Methods

This was a retrospective study of patients who underwent open or EVT for an UIA at our institution between March 2017 and June 2022. Propensity-score matching (PSM) was performed using the 1:1 nearest neighbour method to create two groups (open and EVT) matched by demographics and treatment modality. RAI-measured frailty was used to categorize patients into 4 tiers: robust (0–10), pre-frail (11–20), frail (21–30) and severely frail (≥31). Outcomes of interest were length of stay (LOS), functional dependence at discharge and 30-day readmission.

Results

After PSM, 209 patients were stratified into two groups, open and EVT, respectively. Patients who received EVT were older compared to open surgery (mean ± SD: 62.6 ± 11.4 vs. 60.8 ± 10.6, P < 0.05), however, RAI-measured frailty did not differ significantly between the two groups (median (IQR) open: 3 (2–7), vs. EVT: 3 (2–9)), P = 0.090. Among robust and pre-frail patients, EVT was associated with significantly shorter LOS compared to open surgery, median (IQR): 1 (1–2) vs. 3 (2–4) and 1 (1–2), vs. 3 (2–6); P < 0.001, respectively). Neither functional dependence at discharge nor 30-day readmission rates were different after stratification by frailty.

Conclusion

Patients in the robust and pre-frail tiers experienced significantly shorter LOS after EVT compared to open surgery. We would like to encourage the use of frailty assessment as a pre-operative risk stratification tool patients undergoing treatment of UIAs.