Contrast-induced acute kidney injury following coronary angiography: a cohort study of hospitalized patients with or without chronic kidney disease.

BACKGROUND: Contrast-induced acute kidney injury (CIAKI) has been linked to unfavorable consequences. In routine clinical practice, small increases in serum creatinine (SCr) following coronary angiography tend to be underestimated, especially in patients without chronic kidney disease (CKD). METHODS: We conducted a retrospective observational cohort study to analyze in-hospital and long-term outcomes of CIAKI following coronary angiography in patients with or without CKD (eGFR ≥ 60 mL/min/1.73 m(2)) from January 2008 through December 2009. CIAKI was defined as SCr either ≥ 25% or ≥ 0.5 mg/dL from baseline within 72 h after contrast exposure. Multivariable logistic regression for in-hospital mortality and Cox proportional hazards calculations for long-term mortality and requirement for dialysis were performed. RESULTS: A total of 1160 patients were included in the study. CIAKI occurred in 19% of CKD patients and in 18% of non-CKD patients. In CKD and non-CKD patients, CIAKI was more frequent in patients requiring mechanical ventilation or inotropes or in those given furosemide, and it was associated with adverse in-hospital (prolonged hospitalization, acute dialysis and mortality) and long-term (increased creatinine, initiation of dialysis and mortality) outcomes. In multivariable analysis, CKD patients had greater in-hospital mortality if they developed CIAKI (adjusted OR 8, 95% CI 1.9-34.5, P = 0.005), and non-CKD patients had greater long-term mortality if they developed CIAKI (adjusted HR 2.2, 95% CI 1.2-4.1, P = 0.016). CONCLUSIONS: CIAKI following coronary angiography was associated with adverse in-hospital and long-term outcomes in both CKD and non-CKD patients.