The Pragmatic Impact of Frailty on Outcomes of Coronary Artery Bypass Grafting.

ABSTRACT

BACKGROUND: Although not formalized into current risk assessment models, frailty has been associated with negative postoperative outcomes in many specialties. Using administrative coding, we evaluated the impact of frailty on in-hospital death, complications, and resource use in a nationally representative cohort of patients undergoing isolated coronary artery bypass grafting (CABG). METHODS: Patients aged 18 years and older who underwent isolated CABG across the United States were identified using the 2005 to 2016 National Inpatient Sample. Frailty was defined using a derivative of the validated Johns Hopkins Adjusted Clinical Groups frailty-defining diagnosis indicator. Mortality, length of stay, inflation-adjusted costs, and postoperative complications were evaluated using multilevel multivariable regression. RESULTS: Of an estimated 2,137,618 patients undergoing isolated CABG, 85,879 (4.0%) were considered frail. The proportion of frail patients increased over the study period (nonparametric test for trend P = .002), while annual mortality rates declined (nonparametric test for trend P <.001). Frail patients were older (68.9 ± 10.7 years vs 65.0 ± 10.6 years, P < .001), and more commonly female (32.8% vs 26.2%, P < .001). After adjustment, frailty was associated with increased odds of in-hospital death (adjusted odds ratio [AOR], 2.49; 95% confidence interval [CI], 2.30-2.70; P < .001), major complications (AOR, 2.55; 95% CI, 2.39-2.71; P < .001), increased length of stay (AOR, 1.40; 95% CI, 1.09-2.11; P < .001), and costs (AOR, 1.03; 95% CI, 1.02-1.07; P < .001). CONCLUSIONS: Frailty, as identified by administrative coding, serves as a strong independent predictor of death and complications after CABG. Incorporation of frailty into risk models may aid in counseling patients about operative risk and benchmarking outcomes.