Abstract 3166: Blood Transfusion and Clinical Outcomes in Patients with Acute Myocardial Infarction
Introduction: The safety of red blood cells transfusion (RBC-T) in patients (pts) with acute coronary syndromes is controversial, with some studies suggesting that RBC-T may adversely affect outcome.
Methods: We studied the relationship between RBC-T during hospitalization and 6-months mortality in 2325 pts with acute myocardial infarction (AMI).Propensity score for RBC-T was calculated based on a logistic regression model incorporating age, sex, baseline hemoglobin (Hb), creatinine, diabetes, smoking, blood pressure and heart rate, Killip class, thrombolytic therapy and coronary interventions. The association between RBC-T and mortality was assessed using Cox mode with RBC-T as a time-dependent covariate, adjusting for the propensity to receive RBC-T and nadir Hb prior to RBC-T.
Results: One hundred and ninety one pts (8.2%) received RBC-T. Median nadir Hb was markedly lower in pts receiving RBC-T (8.8 gr/dL [interquartile range 8.2–9.3]) compared with pts not receiving RBC-T (12.8 gr/dL [interquartile range 11.6 –13.9]; P < 0.0001). Mortality increased progressively in pts receiving RBC-T over the 6-months follow-up (Figure⇓). The unadjusted hazard ratio (HR) for mortality in pts receiving RBC-T was 4.1 (95% CI 3.0 –5.7, P < 0.0001). The effect of RBC-T was attenuated but remained significant after adjustments for the propensity to receive RBC-T (HR 2.1; 95% CI 1.4 –3.2, P < 0.0001). However, after adjusting for nadir Hb, the association between RBC-T and mortality was not significant (HR 1.4; 95% 0.9 –2.1, P = 0.09).
Conclusion: The transfusion-associated risk in patients with AMI reflects the severity of the anemia at the time of transfusion and associated comorbidities.