Frailty and Postoperative Outcomes in Patients Undergoing Surgery for Degenerative Spine Disease

Introduction Frailty is defined as a state of decreased reserve and susceptibility to stressors. The relationship between frailty and outcomes after degenerative spine surgery has not been studied. Objectives (1) Determine prevalence of frailty in the degenerative spine population; (2) Describe patient characteristics associated with frailty; (3) Determine the ability of frailty to predict postoperative outcomes. Material and Methods We analyzed 52,671 patients in the National Surgical Quality Improvement Program who underwent degenerative spine surgery. A modified frailty index (mFI) was used to determine the prevalence and severity of frailty as previously described. The association of frailty with postoperative outcomes was determined using multivariate logistic regression. Results Frailty was present in 2,041 patients within the total population (4%), and 8% of patients older than 65 years. Frailty severity increased with increasing age, male sex, African-American race, higher body mass index, recent weight loss, paraplegia or quadriplegia, ASA score, and pre-admission residence in a care facility. Frailty severity was an independent predictor of major complication (OR 1.15 for every 0.10 increase in mFI, 95%CI 1.09–1.22, p < 0.0005), and specifically predicted re-operation for post-surgical infection (OR 1.3, 95%CI 1.16–1.46, p < 0.0005). Prolonged length of stay and discharge to a new facility were also independently predicted by frailty severity ( p < 0.0005). Frailty severity predicted 30-day mortality on unadjusted (OR 2.05, 95%CI 1.69–2.47, p < 0.0005) and adjusted analysis (OR 1.44, 95%CI 1.15–1.81, p < 0.005). Conclusions Frailty is an important predictor of postoperative outcomes following degenerative spine surgery. Preoperative recognition of frailty may be useful for perioperative optimization, risk stratification and patient counseling.