The Hospital Frailty Risk Score and its association with in-hospital mortality, cost, length of stay and discharge location in patients with heart failure short running title: Frailty and outcomes in heart failure

Background: Little is known about frailty amongst patients hospitalized with heart failure (HF) on a national level. Methods: We conducted a retrospective cohort study of patients admitted to hospital for HF in the United States. We examined how low, intermediate and high risk of frailty as defined by the Hospital Frailty Risk Score has changed over time and how it is related to inpatient mortality, length of stay, cost and discharge location. Results: We included 11,626,400 inpatient episodes for HF. The proportions of patients that had low risk, intermediate and high risk of frailty were 80.0% (n = 9,300,873), 19.9% (n = 2,314,001) and 0.1% (n = 11,526). Intermediate or high risk of frailty increased from 9.9% in 2004 to 31.7% in 2014. Length of stay in hospital was greater in the high compared to low risk groups (11.3 days vs 4.6 days, respectively). The cost of admission was also greater in the high risk group ($23,084 +/- 39,681) compared to the low risk group ($9103 +/- 12,768). Intermediate and high risk of frailty groups were associated with increased in odds of mortality (OR 2.38 95% CI 2.22-2.34, p <0.001 and OR 3.05 95%CI 2.57-3.62, p <0.001, respectively) and discharge to nursing facilities (intermediate risk OR 1.52 95%CI 1.50-1.54, p <0.001 and high risk OR 1.60 95%CI 1.35-1.90, p <0.001). Conclusions: Frailty is significant and increasing in a national cohort of patients with HF in the United States. Patients at higher risk of frailty have increased in-hospital mortality, length of stay and inpatient costs, and a greater proportion are discharged to nursing home. (C) 2019 Elsevier B.V. All rights reserved.