174. Generic measures of frailty assessment may be inadequate for the heterogeneity of spine surgery patients; a systematic review of frailty indices used in spine surgery

BACKGROUND CONTEXT The practice of absolute age when considering appropriate surgical management for spine pathology is being replaced by assessments of physiological reserve (or frailty). Many indices of frailty are generic and very few have been designed to meet the needs of the spectrum of surgical spine pathology. PURPOSE To determine the current measures of frailty used in spine surgery practice, and to identify whether disease-specific measures may achieve more robust predictors of outcomes and/or complications. STUDY DESIGN/SETTING Systematic review. PATIENT SAMPLE Adult patients appearing in peer-reviewed articles, with assessment of frailty/sarcopenia with prospective or retrospective cohorts undergoing spine surgery, appearing in publicly available databases. OUTCOME MEASURES Correlation of Frailty indices with perioperative complication rates, patient reported outcomes measures, quality of life outcomes measures where possible. METHODS Search strategies with subject headings and keywords for “frailty,” “elderly” and “spine surgeries” and conditions of interest were defined for three databases (Ovid Medline and Epub Ahead of Print, In-Process \u0026 Other Non-Indexed Citations, Ovid Embase Classic + Embase and Ovid Cochrane Central Register of Controlled Trials). Filters for human studies were used, and were not limited by date or language. The search results were filtered by abstract, and relevant articles were then graded by three authors independently. Articles were grouped by index applied, and where possible classified into disease-specific partitions. The review was conducted in accordance to the PRISMA guidelines and registered with PROSPERO (ID:129928). RESULTS Initial search returned 4,727 results, which were narrowed to 183 after screening by abstract. A total of 34 full text articles were graded and included in the final analysis. The measure most frequently cited was the Modified Frailty Index 11-point or 5-point score (n=18), calculated from inpatient diagnostic codes. The most common pathology was degenerative disease followed by adult spinal deformity (ASD), metastatic disease and trauma/spinal cord injury. Disease-specific indices were found in three conditions, ASD, cervical deformity and metastatic spine disease, and the most number of metrics included in a specific index was 60 (ASD). Increasing frailty index scores were associated with increased rates of perioperative complications, however no association with patient-reported outcome measures have been published. Morphometric analysis has suggested that measures of sarcopenia may have better acuity for predicting complications compared to frailty. CONCLUSIONS The majority of frailty indices applied use generic 5-point or 11-point scales developed outside the scope of spine surgery practice. Very few disease-specific indices have been developed, and a distinct knowledge gap exists on how best to define frailty in discrete and heterogeneous spine pathologies. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.