Anaemia at the moment of admittance is associated with higher heart failure and mortality among patients with acute coronary syndrome
© BioMed Central Ltd. 2007
Published: 22 March 2007
The search for novel and modifiable risk factors in acute coronary syndrome (ACS) can open new strategies. We decided to evaluate the prevalence of anaemia and determine its influence on the prognosis of hospitalized ACS patients.
Patients and methods
Four hundred and twenty-eight consecutive patients hospitalized for ACS between 2005 and 2006 in a coronary care unit (CCU) of a cardiology department of a tertiary hospital were studied. During their hospitalization we registered cardiovascular risk factors; we determined the presence of microalbuminuria (>3 mg/dl) in a 24-hour urine sample. We also took blood samples during the first 24 hours of their admittance to the CCU for a complete haemogram, levels of total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, creatinine, creatinine clearance (Cockroft-Gault equation), glucose, HbAc1, high-sensibility C-reactive protein and a follow-up of levels of Troponin, CK and CK-MB.
The prevalence of anaemia (Hb < 11 g/dl in women and Hb < 12 g/dl in men) in patients with an ACS was 15.4%. This group was characterised by the following: woman (P < 0.0001), higher age (P = 0.0001), less weight (P = 0.01), higher frequency of high blood pressure (P = 0.0001), diabetes mellitus (P = 0.0001), history of ischaemic heart disease (P = 0.002) and peripheral artery disease (P = 0.0001). This group presented a major proportion of the NSTEMI (P = 0.015), higher level of renal dysfunction (77% to 32%, P = 0.0001), and microalbuminuria (61% to 32%, P = 0.0001). Patients with anaemia presented a worse intrahospital prognosis: major incidence of cardiac insufficiency (42% to 20%, P = 0.0001), refractory angina pectoris (14% to 6%, P = 0.01), more electric complications (12% to 9%, P = 0.01) and a higher mortality (14% to 7%, P = 0.009). The presence of anaemia was an independent predictor of cardiac insufficiency and death at the moment of admittance to the CCU (OR = 2.20, 95% CI = 1.10–4.35; P = 0.002).
The presence of anaemia is a powerful predictor of a worse prognosis in patients with ACS. Anaemia is associated with other factors of a worse prognosis such as renal dysfunction, peripheral artery disease and diabetes mellitus.