Outcomes of Octogenarians and Nonagenarians in a Contemporary Cardiac Care Unit　― Insights From 2,242 Patients Admitted Between 2019 and 2021 ―

Background: The number of octo- and nonagenarians admitted to cardiac care units (CCUs) has been increasing in the context of an aging society; however, clinical details and outcomes for these patients are scarce. Methods and Results: Data from 2,242 consecutive patients admitted to the CCU between 2019 and 2021 (age <80 years, 1,390 [62%]; octogenarians, 655 [29%]; nonagenarians, 197 [8.7%]) were reviewed using the in-hospital database for the Tokyo CCU Network. The primary cause of admission was acute coronary syndrome in younger patients and octogenarians (58% and 49%, respectively) and acute heart failure (AHF) in nonagenarians (42%). The proportions of females, underweight, hypertension, atrial fibrillation, myocardial infarction, stroke, previous heart failure, anemia, and malnutrition were higher among octo- and nonagenarians than among younger patients. In-hospital and 1-year mortality rates were greater in octo- and nonagenarians (younger vs. octogenarian vs. nonagenarian, 2.0% vs. 3.8% vs. 5.6% and 4.1% vs. 11.9% vs. 19.0%, respectively). Multivariate analysis revealed that 1-year mortality was associated with octo-/nonagenarian status (odds ratio [OR] 2.24 and 2.64), AHF (OR 2.88), body mass index (OR per 1-kg/m(2) 0.91), and albumin concentration (OR per 1-g/dL 0.27). Conclusions: Approximately 40% of patients admitted to the CCU were octo- or nonagenarians, and being an octo- or nonagenarian, having AHF, a lower body mass index, and lower albumin concentrations were associated with 1-year mortality after CCU admission.