A Comparison Between Two Different Definitions of Contrast-Associated Acute Kidney Injury for Long-Term Mortality in Patients with Chronic Kidney Disease Undergoing Coronary Angiography

Wenwei Feng,&ast; Jiancong Zhou,&ast; Zhubin Lun, Dianhua Zhou, Peiwen Li, Jianfeng Ye Department of Cardiology, Dongguan Hospital of Guangzhou University of Chinese Medicine, Dongguan, Guangdong, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Jianfeng Ye, Department of Cardiology, Dongguan Hospital of Guangzhou University of Chinese Medicine, Dongguan, Guangdong, People’s Republic of China, Email yipjf@hotmail.comBackground: Contrast-associated acute kidney injury (CA-AKI) is a prevalent complication following coronary angiography (CAG). However, there is ongoing controversy surrounding its precise definition. Although previous studies have demonstrated the successful application of appropriate definitions in managing high-risk CA-AKI patients, there remains limited research on the association between different definitions and prognosis specifically in patients with chronic kidney disease (CKD).Methods: A total of 4197 CKD patients undergoing coronary angiography (CAG) were included in this study. Two definitions of contrast-associated acute kidney injury (CA-AKI) were used: CA-AKIA, which was defined as an increase of ≥ 0.5 mg/dL or > 25% in serum creatinine (SCr) from baseline within 72 hours after CAG, and CA-AKIB, which was defined as an increase of ≥ 0.3 mg/dL or > 50% in SCr from baseline within 48 hours after CAG. Cox regression analysis was employed to assess the association between these two definitions and long-term mortality. Additionally, population attributable risks (PARs) were calculated to evaluate the impact of CA-AKI definitions on long-term prognosis.Results: During the median follow-up period of 4.70 (2.50– 7.78) years, the overall long-term mortality was 23.6%, and the long-term mortality in patients with CA-AKI according to both CA-AKIA and CA-AKIB criteria were 33.5% and 33.8%, respectively. We found that CA-AKIA (HR: 1.45, 95% CI: 1.23– 1.70, p< 0.001) and CA-AKIB (HR: 1.44, 95% CI: 1.23– 1.69, p< 0.001) were associated with long-term mortality. The PARs were the highest for CA-AKIA (5.87%), followed by CA-AKIB (5.70%).Conclusion: Contrast-associated acute kidney injury (CA-AKI) is a frequently observed complication in CKD patients undergoing coronary angiography (CAG), and both definitions of CA-AKI are significantly correlated with a poor long-term prognosis. Consequently, in the clinical management of CKD patients, it is crucial to prioritize CA-AKI, irrespective of the specific CA-AKI definition used.Keywords: contrast-associated acute kidney injury, chronic kidney disease, definitions, long-term mortality, population attributable risks