Adequacy of endogenous erythropoietin levels and mortality in anaemic heart failure patients.

Abstract

We examined the adequacy of endogenous erythropoietin (EPO) levels for the degree of anaemia in patients with chronic heart failure (CHF) and its relation to prognosis. We studied 74 anaemic CHF patients from a cohort of 240 patients. The adequacy of endogenous EPO levels was assessed by derived observed/predicted (O/P) ratio. A ratio value < 0.92 indicates EPO levels lower than expected, whereas a value > 1.09 indicates EPO levels higher than expected. The primary endpoint was mortality. During a median follow up of 4.9 years, 35 of the 74 (47.3%) anaemic patients died. EPO levels lower than expected were observed in 29 patients (39%), whereas EPO levels higher than expected were present in 22 anaemic patients (29%). The Kaplan-Meier analysis revealed that anaemic patients with EPO levels higher than expected had a significantly higher mortality rate compared to patients with EPO levels as expected or EPO levels lower than expected (log-rank: P = 0.024). A higher O/P ratio was an independent predictor of increased mortality risk adjusted for variables including age, sex, haemoglobin, NT-proBNP, and renal function; hazard ratio (HR): 1.020 95%CI (1.004-1.036), P = 0.012. EPO levels higher than expected, suggesting resistance to the hormone, are common in CHF patients and are associated with a higher mortality.