The Prognostic Significance of Chronic Kidney Disease on the All-Cause Death of Ischemic Heart Failure in the Chinese Population: A Prospective Cohort Study

Objective: Our team tried to explore the impact of chronic kidney disease (CKD) on all-cause death among ischemic heart failure (IHF) patients. Methods: From December 2015 to June 2019, IHF patients were continuously recruited in the Department of Cardiology, Guangdong Provincial People's Hospital. Participants were tracked through telephone interviews until October 15, 2020, or until the clinical endpoints appeared. The clinical endpoints were defined as all-cause death. The date of death or the last follow-up date minus the discharge date was used to calculate the follow-up time. Results: A total of 1568 IHF patients (mean age 63.5 +/- 11.0 years old, 85.8% male) were included in this study. Using the estimated glomerular filtration rate (eGFR) of 60 mL/min/1.73 m(2) as the dividing line, IHF patients were divided into non-CKD group (n = 1,134) and CKD group (n = 434). After a median follow-up of 2.1 years, the all-cause death of non-CKD and CKD patients was 6.1/100 person-years and 13.7/100 person-years, respectively, and the incidence rate ratio was 2.24 (95% CI: 1.75-2.88; p value <0.001). The cumulative all-cause death of non-CKD and CKD patients were 19.4% and 40.7%, respectively (p value <0.001). CKD was an independent predictor of all-cause death in IHF patients (HR: 1.35, 95% CI: 1.03-1.76, p value = 0.029). Among IHF patients, in 8 subgroups, the all-cause death of CKD patients was consistently higher than that of non-CKD patients. Among IHF patients, the risk of all-cause death gradually increased when eGFR gradually decreased. Conclusion: Among IHF patients, CKD is a significant risk factor for all-cause death.