Preoperative Frailty Status Measured by Clinical Risk Analysis Index and Adverse Events After Endoscopic Endonasal Transsphenoidal Resection of Pituitary Adenoma: Single Center Prospective Case Series

Introduction: The endoscopic endonasal transsphenoidal approach (EEA) is the most common and favored approach for the resection of pituitary adenomas (PA), though is not without the inherent risk of postoperative adverse events. The Clinical Risk Analysis Index (RAI-C) is a tool utilized for measuring baseline patient frailty. We present preliminary data from a prospective single-institution cohort tracking the relationship between RAI-C and adverse events following EEA for PA resection.

Methods: Baseline patient frailty was measured using the RAI-C scoring questionnaire. Descriptive statistics were reported in this preliminary case series. Discriminatory accuracy of RAI-C for the primary endpoint of adverse event was assessed using area under the receiver operating characteristic (ROC) curve analysis and C-statistics.

Results: This case series consisted of 60 patients. In terms of RAI-C frailty score, there were 13 patients with 0-10, 27 with 11-20, and 20 with 21+. There were 9 adverse events which included non-home discharge (N=5), reoperation (N=5), major complication (N=2), and/or mortality (N=2). Both deaths occurred in patients with RAI-C>30. Descriptively, the rate of adverse event occurrence trended upwards with increasing RAI-C score: score 0-10 with 7.7%, 11-20 with 11.1%, and 21+ with 25%. The RAI-C predicted adverse events with robust discriminatory accuracy (C-statistic 0.714, 95% CI: 0.514-0.913, P=0.042). By contrast, the 5-Factor Modified Frailty Index (mFI-5) performed with poor discriminatory accuracy (C-statistic 0.664, 95% CI: 0.0.464-0.0.865, P=0.0.118).

Conclusion : This is the first prospective study to measure baseline frailty with RAI-C and track adverse events in patients following EEA for PA resection, which preliminarily shows that baseline frailty status as measured by RAI-C holds promise for the prediction of adverse events. Further analysis in a larger prospective series is expected to improve the validity of the present findings and may later guide early quality improvement in neurosurgical clinics.