Background: Elevated C-reactive protein (CRP) was shown to be associated with an increased risk for acute kidney injury (AKI) in ST elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI), however, the optimal time frame to measure CRP for risk stratification is not known. We evaluated the relation between the change in CRP over time (CRP velocity-CRPv) and AKI among STEMI patients treated with primary PCI.
Methods: We included 801 STEMI who presented between 2007 and 2017 and had their CRP measured with a wide range assay (wr-CRP) at least twice during the 24 h after admission. CRPv was defined as the change in wr-CRP concentration (mg/l) divided by the change in time (in h) between the two measurements. Patient's medical records were reviewed for occurrence of AKI.
Results: Mean age was 62 ± 16 and 80% were males. Patients with AKI had significantly higher CRPv (1.47 versus 0.4 mg/l/h, p < 0.001). In a multivariate regression model CRPv was independently associated with AKI (OR 1.03, 95% CI 1.01-1.0 5, p = 0.001). On receiver operating characteristic (ROC) curve the optimal cutoff value of CRPv to predict AKI was measured as more than 0.8 mg/l/h, with 70% sensitivity and 65% specificity (AUC 0.712, 95% CI 0.64-0.78, p < 0.001).
Conclusion: CRPv might be an independent and rapidly measurable biomarker for AKI following primary PCI in STEMI patients.
Keywords: Acute kidney injury; Acute myocardial infarction; Biomarkers; C-reactive protein.