Iron Status and Mortality in Stable and Unstable Coronary Artery Disease Patients

Abstract

ObjectiveWe sought to assess the relationship of indices of iron status and the risk of all‐cause and cardiovascular disease (CVD) mortality among coronary artery disease (CAD) patients with and without acute coronary syndrome (ACS).Methods and results: The study sample included 1181 CAD patients (692 with ACS and 489 with stable CAD). Cox proportional hazards regression models were used to estimate the association of circulating iron, ferritin and hepcidin with all‐cause and CVD mortality. After an average follow‐up of 4.1 years, 144 deaths were recorded, 108 of which were due to CVD. After adjusting for clinical CVD risk factors and inflammatory markers, ferritin and hepcidin were positively associated with CVD mortality in ACS group, hazard ratios (HR) (95% CIs) Q4 versus Q1: 4.05 (1.53‐10.7) and 2.86 (1.09‐7.48), respectively. Circulating iron showed an inverse association with CVD mortality in stable CAD group, HR (95% CI) Q4 versus Q1: 0.23 (0.08‐0.63). The discriminative abilities when including and excluding iron status into traditional clinical CVD models were 2.1% in all CAD patients, 3.1% in ACS patients, and 3.6% in stable CAD patients.ConclusionIron status was different in stable and unstable CAD patients. Circulating iron was inversely associated with the risks of mortality in stable CAD patients, while plasma ferritin and hepcidin were positively associated with mortality risks in ACS patients.