LAUSR

BACKGROUND Patients with frailty consistently experience higher rates of perioperative morbidity and mortality; however, costs attributable to frailty remain poorly defined. We sought to identify older patients with and without frailty using a validated, multidimensional frailty index and estimated the attributable costs in the year following major, elective non-cardiac surgery. METHODS We conducted a retrospective population-based cohort study of all patients >66 years having major, elective non-cardiac surgery between April 1, 2012 and March 31, 2018 using linked health data obtained from an independent research institute (ICES) in Ontario, Canada. All data were collected using standard methods from the date of surgery to the end of 1-year follow up. The presence or absence of preoperative frailty was determined using a multi-dimensional frailty index. Our primary outcome was total health system costs in the year following surgery using a validated patient-level costing method capturing direct and indirect costs. Secondary outcomes included costs to postoperative days 30 and 90 along with sensitivity analyses and evaluation of effect modifiers. RESULTS Of 171,576 patients, 23,219 (13.5%) were identified with preoperative frailty. Unadjusted costs were higher among patients with frailty (ratio of means (RoM) 1.79, 95% confidence interval (CI) 1.76 to 1.83). After adjusting for confounders, an absolute cost increase of $11,828 CAD (RoM 1.53; 95% CI 1.51 to 1.56) was attributable to frailty. This association was attenuated with additional control for comorbidities (RoM 1.24, 95% CI 1.22 to 1.26). Among contributors to total costs, frailty was most strongly associated with increased post-acute care costs. CONCLUSIONS For patients with preoperative frailty having elective surgery, we estimate that attributable costs are increased 1.5-fold in the year after major, elective non-cardiac surgery. These data inform resource allocation for patients with frailty.