Impact of iron deficiency on prognosis of heart failure patients with preserved ejection fraction

Abstract

Objective: To investigate the impact of iron deficiency (ID) on prognosis in heart failure patients with preserved ejection fraction (HFpEF). Methods: A total of 215 consecutive patients with HFpEF, who visited the cardiovascular outpatient department of Beijing Anzhen Hospital, were enrolled in this prospective study. The plasma ferritin level and transferin saturation were measured. Patients were divided into two groups: ID group and non-ID group. ID patients were further divided into absolute ID subgroup and functional ID subgroup. Patients were followed up to 1 year. The endpoints of the study were all-cause mortality and rehospitalization for heart failure (HF). The independent predictors of outcome were determined by Cox regression model. The quality of life of patients was evaluated at the end of the follow-up. Results: The age of this patient cohort was (67±8) years, 39.1% patients were male. The prevalence of ID was 54.4%. Within one year of follow-up, 37 patients (17.2%) died and 70 patients (32.6%) were rehospitalized for HF. Compared to non-ID group, patients in ID group were older, had higher heart rate, lower plasma hemoglobin level and estimated glomerular filtration rate (eGFR) value, had a higher prevalence of anemia and chronic kidney disease (P all<0.05). Kaplan-Meier curves showed that all-cause mortality and rehospitalization for HF in HFpEF patients with ID were higher than patients without ID, and prognosis was similar between patients with absolute ID and functional ID. Multivariable regression analysis showed that ID was an independent predictor for all-cause mortality and rehospitalization for HF in HFpEF patients. The of 6 minutes walking distance was shorter ((356.0±98.3)m vs. (389.2±94.3)m, P=0.023), and the value in Kansas city cardiomyopathy questionnaire was lower ((58.06±10.43) m vs. (61.51±11.64) m, P = 0.039) in patients with ID than patients without ID. Conclusion: In patients with chronic HFpEF, ID is an independent predictor for all-cause mortality and rehospitalization for HF at one year of follow-up, independent of the types of ID.