Impact of anaemia on the prognosis of myocardial infarction in black Africans

OBJECTIVE: Anaemia is increasingly being described as a negative predictor of outcome after myocardial infarction. The objective of our study was to assess the prognosis post myocardial infarction in the short and medium term in black Africans with chronic anaemia. METHODS: We carried out a comparative case-control study on 272 patients (93 anaemic and 179 non-anaemic) hospitalised for myocardial infarction at the Cardiology Institute of Abidjan. One group included 93 patients who presented with anaemia concurrent with the myocardial infarction (haemoglobin level low: 13 g/dl for males and 12 g/dl for females, respectively). The other group comprised 172 patients who presented without anaemia during the acute phase of myocardial infarction. The haemoglobin rate was measured at admission, as were the biological markers of myocardial infarction. RESULTS: The mean age was 53.5 years for the anaemic patients and 52.6 years for the non-anaemic patients. We noticed a clear male predominance in both populations (81.7 vs 78.8%; p = 0.56). The mean haemoglobin level was lower in the anaemic patients compared to that in the non-anaemic patients (10.2 vs 15 g/dl). The anaemic patients were eight times more at risk for an unfavourable outcome (complications or death) compared to the non-anaemic patients (91.4 vs 57%; OR = 8.02; 95% CI: 3.5–19.07; chi(2) = 33.74; p < 0.0001). The anaemic patients were 3.7 times more at risk for right ventricular failure (NYHA class II and III) compared to the control population (69.9 vs 38.5%; OR = 3.7; 95% CI: 08–6.60; chi(2) = 24.06; p < 0.0001) and six times more at risk for cardiogenic shock (24.7 vs 5.3%; OR = 6.21; 95% CI: 2.56–15.43; chi(2) = 22.89; p < 0.0001). The mortality rate was significantly higher in the anaemic than the non-anaemic patients (35.5 vs 12.8%; OR = 3.73; 95% CI: 1.94–7.19; chi(2) = 19.18; p < 0.0001). CONCLUSION: Anaemia is an independent risk factor for a poor prognosis during the acute phase of myocardial infarction in black Africans.