Relationship of plasma erythropoietin to long-term outcome in acute coronary syndrome.
BACKGROUND
Erythropoietin has been related to adverse prognosis in patients with heart failure, but it is unknown whether it adds prognostic information in acute coronary syndrome.


METHODS
Plasma erythropoietin was measured on admission with enzyme-linked immunosorbent assay in 627 patients. Patients were divided into three groups depending on their erythropoietin level and followed for myocardial infarction (MI) (median 6 months) and mortality (median 39 months). Cox regression models were used to evaluate erythropoietin compared to clinical variables; age, gender, diabetes, smoking, prior MI, heart failure, hypertension and revascularization. In a second Cox regression model, laboratory markers were assessed; hemoglobin, estimated glomerular filtration rate (eGFR), C-reactive protein (CRP), cardiac troponin T (cTnT) and N-terminal pro-brain-natriuretic peptide (NT-proBNP).


RESULTS
Patients with the highest erythropoietin level (>8.8 mU/mL, n=205) had a 47% increased mortality (HR 1.47, 95% CI 1.04-2.06, p=0.028) when adjusted for clinical variables. Compared to laboratory risk markers, erythropoietin added prognostic information (HR 1.59, 95% CI 1.05-2.38, p=0.027) when adjusted for hemoglobin, eGFR and CRP. Erythropoietin (HR 1.21, 95% CI 0.79-1.86, p=0.387) was no longer significantly associated with mortality when cTnT and NT-proBNP were added. Erythropoietin was not related to the risk of future MI (HR 1.24, 95% CI 0.65-2.33, p=0.513).


CONCLUSIONS
Elevated erythropoietin level was associated with increased mortality in patients admitted with possible ACS when adjusted for clinical variables, or for kidney function and hemoglobin. However, erythropoietin does not add prognostic information when markers of myocardial necrosis and dysfunction are available in ACS.
Szummer
Karolina
K
Department of Medicine H7, Section of Cardiology, Huddinge, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden. karolina.szummer@karolinska.se
Lindahl
Bertil
B
Sylvén
Christer
C
Jernberg
Tomas
T
D054058:Acute Coronary Syndrome / Q000097:blood* / Q000401:mortality*; D000368:Aged; D002097:C-Reactive Protein / Q000378:metabolism; D004921:Erythropoietin / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000401:mortality*; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012307:Risk Factors; D020107:Troponin T / Q000097:blood
D006454:Hemoglobins; D010446:Peptide Fragments; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D004921:Erythropoietin; D020097:Natriuretic Peptide, Brain; D002097:C-Reactive Protein