Abstract
BACKGROUND: We compared 1-year functional outcomes for 4 cardiac surgery patient groups: comparison (without preoperative frailty or postoperative delirium [POD]), frailty only (with preoperative frailty only), POD only (with POD only), and frailty-POD (combined frailty and POD). METHODS: Consecutive cardiac surgery patients (n = 298) at a university hospital were assessed for preoperative frailty using Fried's phenotype, and POD was assessed daily for 10 days after surgery using the Confusion Assessment Method. Functional outcomes (Barthel Index for activities of daily living [ADL]) and all-cause mortality were evaluated 1-year after surgery. RESULTS: Preoperative frailty presented in 85 of participants (28.5%) and POD in 38 (12.8%). Frail participants were at increased risk for POD (odds ratio = 4.9; P < .001). Overall, 1-year mortality was 4.0% (n = 12) and functional change was 0.4 ± 11.0 Barthel points. Controlling for age, cardiac risk, and baseline ADL, frailty-only and comparison participants had comparable 1-year functional outcomes. The POD-only group had greater mortality (adjusted hazard ratio = 23.9; P = .01), whereas the combined frailty-POD group had the greatest ADL decline (β = -23.7; P = .01) and the highest mortality (adjusted hazard ratio = 30.2; P = .006) compared with the comparison group. CONCLUSIONS: Preoperative frailty alone did not negatively affect cardiac surgery patients' functional outcomes up to 1 year, but coexisting frailty and POD led to substantial loss of independence on 3 to 4 ADLs and a 30.2-fold higher likelihood of dying 1 year after surgery. Because frailty led to a 4.9-fold increase in POD risk, frailty may serve as a presurgical screen to identify patients who would likely benefit from delirium prevention and functional recovery programs to maximize 1-year postsurgical outcomes.