The role of anti-oxidant markers in predicting the severity of chronic heart failure

Introduction Heart failure is a systemic disease characterized by a progressive increase in congestion, inflammation and oxidative stress over time. Oxidative stress is a phenomenon caused by an imbalance between the production of free radicals and the ability of the body to counteract or detoxify their harmful effects through neutralization by antioxidants. Objective To evaluate the potential applicability of anti-oxidant parameters (Superoxide dismutase and Glutathione Peroxidase and Total Anti-oxidant Capacity) in predicting morbidity and mortality in a cohort of outpatients with Chronic Heart Failure (CHF). Method Superoxide dismutase (SOD) and Glutathione peroxidase (GPx) activities as well as total anti-oxidant capacity (TAC) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were determined in 118 CHF patients with left ventricle ejection fraction≤50%. Results Patients with class NYHA III-IV had significantly lower SOD activity than those with NYHA II. GPx activity was lower in patients with clinical signs of flood overload. Both SOD and GPx activities showed a significant decrease in severe LV dysfunction with LVEF<30% (P=0.006 and P<0.001). GPx activity decreased significantly in subjects with moderate or greater tricuspid regurgitation and right ventricle dysfunction.During a median follow-up of 20.6 months, 27 patients (23.7%) were hospitalized, and 30 patients (26.3%) died. Total anti-oxidant capacity was found to predict readmission as evaluated by a Cox multivariate regression analysis with a hazard ration (HR) of 3.38 (P=0.003), whereas NT pro-BNP remained independent predictor of mortality with a HR of 3.2 (P=0.037). GPx activity<16U/gHb was significantly connected to higher mortality (P=0.041). Conclusion Decreased GPx activity strongly correlated with severity of heart failure. Total anti-oxidant capacity may be a useful predictor of rehospitalization in HF.