Background and objectives: The Hospital Frailty Risk Score (HFRS) is an International Classification of Disease 10th Revision-based scale that was originally designed for, and validated in, the assessment of patients 75 years or older presenting in an acute care setting. This study highlights central tenets inherent to the concept of frailty; questions the logic behind, and utility of, HFRS' recent implementation in the neurosurgical literature; and discusses why there is no useful role for HFRS as a frailty-based neurosurgical risk assessment (FBNRA) tool.

Methods: The authors performed a systematic review of the literature per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, including all cranial and spinal studies that used HFRS as their primary frailty tool. Seventeen (N = 17) studies used HFRS to assess frailty's impact on neurosurgical outcomes. Thirteen total journals, 10 of which were neurosurgical journals, including the highest impact factor journals, published the 17 papers.

Results: Increasing HFRS score was associated with adverse outcomes, including prolonged length of stay (11 of 17 studies), nonroutine discharge (10 of 17 studies), and increased hospital costs (9 of 17 studies). Four different HFRS studies, of the 17, predicted one of the following 4 adverse

Outcomes: worse quality of life, worse functional outcomes, reoperation, or in-hospital mortality.

Conclusion: Despite its rapid acceptance and widespread proliferation through the leading neurosurgical journals, HFRS lacks any conceptual relationship to the frailty syndrome or FBNRA for individual patients. HFRS measures acute conditions using International Classification of Disease 10th Revision codes and awards "frailty" points for symptoms and examination findings unrelated to the impaired baseline physiological reserve inherent to the very definition of frailty. HFRS lacks clinical utility as it cannot be deployed point-of-care at the bedside to risk stratify patients. HFRS has never been validated in any patient population younger than 75 years or in any nonacute care setting. We recommend HFRS be discontinued as an individual FBNRA tool.