Blood Transfusion and the Risk of Contrast-Induced Nephropathy Among Acute Coronary Syndrome Patients Undergoing Percutaneous Coronary Intervention

Introduction: Emerging scientific and clinical evidence suggests that blood transfusion might be risk factor for acute kidney injury. Hypothesis: Blood transfusion is independently associated with contrast-induced nephropathy (CIN) in acute coronary syndrome (ACS) patients undergoing PCI. Methods: Retrospective cohort study from the NCDR CathPCI Registry (2009-2014) (n=1,756,864). Primary outcome was CIN defined as rise in serum creatinine peak post-procedure ≥ 0.5 mg/dl or ≥ 25% above baseline. Results: CIN developed in 9.0% of the cohort; these patients were older (66.0 vs. 64.0 years; P<0.01), more often female (43.2% vs. 31.9%; P<0.01), and had more baseline comorbidities including DM (46.1%), hypertension (85.1%), and lower baseline GFR. Blood transfusion was utilized in 38,626 (2.2%) of patients. The adjusted OR for the risk of CIN with transfusion in the overall sample, patients with major bleeding, and patients with no bleeding were 4.87 (4.71-5.04), 2.21 (2.12-2.31), and 4.80 (4.40 - 5.24) respectively (Table). Association of CIN with transfusion was significantly increased across all pre-procedure hemoglobin (Hgb) levels and in stepwise fashion with increasing Hgb levels and regardless of post-procedure bleeding (Hgb <=10: adjusted OR (95%CI) 2.90 (2.75-3.05); Hgb >10 to <=13: 5.26 (5.06-5.48); Hgb >13 to <=15: 6.37 (5.99-6.78); Hgb >15 g/dl: 7.03 (6.43-7.67); Ptrend <0.01). Conclusions: Blood transfusion is strongly associated with CIN in ACS patients undergoing PCI. Whether a restrictive blood transfusion strategy lowers the risk of contrast nephropathy should be investigated.