Letter to Editor: Does the “Hospital Frailty Risk Score” Measure Frailty in Patients Undergoing Surgery for Primary Spinal Cord Tumors?

Abstract

CordTumors" recently published in the January 2022 issue of Global Spine Journal. The study used the Hospital Frailty Risk Score (HFRS) to assess the impact of frailty on patients undergoing surgery for primary tumors of the spinal cord and meninges, using cases extracted from the Nationwide Inpatient Sample (NIS) database. Based on the HFRS, patients were dichotomized into: Non-Frail (HFRS <5) and Frail (HFRS ≥5), with 21.2% patients classified as Frail. 1 The authors concluded that Frail patients were associated with increased postoperative complications, hospital costs, non-routine discharge, and prolonged length of stay LOS. 1 Therefore, they proposed the use of the HFRS as a novel neurosurgical frailty index for patients undergoing surgery for primary spinal cord tumors. We appreciate the authors' efforts in exploring neurosurgical outcome research; however, we are seeking clarification regarding the use of the HFRS in this study.The original HFRS paper published by Gilbert et al. 2 developed the index using >1000 ICD-10-CM codes overrepresented in older hospitalized adults (≥75 years of age), who had diagnoses associated with what they termed "frailty". However, the authors only validated the HFRS for older patients ≥75 years old and also presenting in the acute care setting. Therefore, how are the authors applying this scoring system to a much younger patient population of ≥18 years of age? Have they validated the HFRS for all adult patients? Furthermore, with respect to the statistical methodology, the calculated c-statistics, model discrimination, for 30-day mortality, prolonged hospital LOS and 30-day readmission were .60, .68 and .56 respectively, which was below the normal acceptable epidemiological threshold. 2

Commentary: The Limited Utility of the Hospital Frailty Risk Score as a Frailty Assessment Tool in Neurosurgery: A Systematic Review

“…4 HFRS is criticized for being computationally impossible to distinguish whether frailty assessment occurs preoperatively or postoperatively, which is essential for neurosurgical frailty research. 5,6,11 Hence, the application of the tool in neurosurgical population introduces inaccuracies in the measured "frailty" of the surgical population and hence does not have practical utility in the context of guiding personalized intervention decisions or generating treatment guidelines without further validation studies. However, this does not entirely discredit previous studies using HFRS to predict mortality; rather, it might be possible to reframe their interpretation.…”

“…In comparison with existing literature, the paper aligns with other studies that have criticized HFRS for its limitations and lack of validation in specific patient populations. 6,[11][12][13][14] It underscores the importance of using frailty assessment tools that are appropriate for the context and have been rigorously validated, such as the Risk Analysis Index, which has shown strong discriminatory accuracy in predicting surgical outcomes across various age groups. [15][16][17] The authors also present a brief comparison of frailty scores based on the 10 core principles defined in Table 4 that offers comparison for these tools.…”