Frailty and Sarcopenia: Impact on Outcomes Following Elective Degenerative Lumbar Spine Surgery

Study Design. This is a retrospective review of prospectively collected data. Objective. The aim was to evaluate the impact of frailty and sarcopenia on outcomes after lumbar spine surgery. Summary of Background Data. Elderly patients are commonly diagnosed with degenerative spine disease requiring surgical intervention. Frailty and sarcopenia result from age-related decline in physiological reserve and can be associated with complications after elective spine surgery. Little is known about the impact of these factors on patient-reported outcomes (PROs). Methods. Patients older than 70 years of age undergoing elective lumbar spine surgery were included. The modified 5-item frailty index (mFI-5) was calculated. Sarcopenia was defined using total psoas index, which is obtained by dividing the mid L3 total psoas area by VB area (L3-TPA/VB). PROs included Oswestry disability index (ODI), EuroQual-5D (EQ-5D), numeric rating scale (NRS)-back pain, NRS leg pain (LP), and North American Spine Society (NASS) at postoperative 12 months. Clinical outcomes included length of stay (LOS), 90-day readmission and complications. Univariate and multivariable regression analyses were performed. Results. Total 448 patients were included. The mean mFI-5 index was 1.6±1.0 and mean total psoas index was 1.7±0.5. There was a significant improvement in all PROs from baseline to 12 months ( P <0.0001). After adjusting for age, body mass index, smoking status, levels fused, and baseline PROs, higher mFI-5 index was associated with higher 12-month ODI ( P <0.001), lower 12-month EQ-5D ( P =0.001), higher NRS-L P ( P =0.039), and longer LOS ( P =0.007). Sarcopenia was not associated with 12-month PROs or LOS. Neither sarcopenia or mFI-5 were associated with 90-day complication and readmission. Conclusions. Elderly patients demonstrate significant improvement in PROs after elective lumbar spine surgery. Frailty was associated with worse 12 months postoperative ODI, EQ-5D, NRS-LP scores, and longer hospital stay. While patients with sarcopenia can expect similar outcomes compared with those without, the mFI-5 should be considered preoperatively in counseling patients regarding expectations for disability, health-related quality of life, and leg pain outcomes after elective lumbar spine surgery. Level of Evidence. 3.