Biomarkers of Zinc and Copper Status and Associated Factors in Outpatients with Ischemic and Non-Ischemic Heart Failure

Background: Few studies have explored the impact of ischemic and non-ischemic etiologies of heart failure and other factors associated with heart failure on zinc and copper status. This study examined zinc and copper status in 80 outpatients with ischemic (n = 36) and non-ischemic (n = 44) heart failure and associations with biodemographic, clinical, biochemical, and nutritional parameters. Materials: Biomarkers of plasma zinc and copper, copper-zinc ratio, 24-h urinary zinc excretion, ceruloplasmin, and dietary intake of zinc and copper were assessed. Plasma zinc and copper and urinary zinc were measured by inductively coupled plasma mass spectrometry (ICP-MS). Results: Patients with ischemic heart failure showed lower dietary zinc intake and higher dietary copper intake (both p = 0.02). Zinc and copper in plasma, copper-zinc ratio, ceruloplasmin, and 24-h urinary zinc excretion showed no statistical differences between the groups (all p >= 0.05). An inverse association was found between age (beta =-0.001; p = 0.005) and the use of diuretics (beta = -0.047; p = 0.013) and plasma zinc. Copper levels in plasma (beta = 0.001; p < 0.001), and albumin (beta = 0.090; p<0.001) were directly associated with plasma zinc. A positive association was found between ceruloplasmin (beta = 0.011; p < 0.001), gamma-glutamyl transferase (beta = 0.001; p < 0.001), albumin (beta = 0.077; p = 0.001), and high-sensitivity c-reactive protein (beta = 0.001; p = 0.024) and plasma copper. Conclusion: Zinc and copper biomarkers in clinically stable patients with heart failure did not seem to be responsive to the differences in zinc and copper intake observed in this study, regardless of heart failure etiology. The predictors of plasma zinc and copper levels related to oxidative stress and inflammation should be monitored in heart failure clinical practice.