Global Risk Factors of Contrast-Induced Acute Kidney Injury: Systematic Review and Meta-Analysis

Background: Administration of iodinated contrast is common but may be associated with contrast-induced acute kidney injury (CI-AKI), particularly in at-risk patients. There is no recent systematic review of potentially modifiable risk factors. Methods: We searched MEDLINE, Embase and the Cochrane Database of Systematic Reviews (to 30th June 2019) for observational studies assessing risk factors associated with CI-AKI. Twelve potentially modifiable risk factors were finally included in this thematic review and meta-analysis. Random or fixed meta-analysis was performed to derive the adjusted odds ratio (aOR), and the population attributable risk (PAR) was calculated for each risk factor globally and by region. Findings: We included 157 studies (2,297,863 participants). Most studies had a low risk of bias. The global incidence of CI-AKI was 5.4%. The potentially modifiable risk factors included high contrast volume (PAR 33%), eight cardiovascular risk factors (diuretic use, multivessel coronary artery disease, acute coronary syndrome, hypertension, hypotension, heart failure, reduced left ventricular ejection fraction and intra-aortic balloon pump use) (combined PAR 76.2%) and three noncardiovascular risk factors (renal dysfunction, diabetes mellitus and anaemia) (combined PAR 47.4%) with geographical differences. In Asia, the PAR of high contrast agent volume ranks first with limited data, while diuretic use ranks first in Europe and North America. The PAR of heart failure was higher in Europe, as was renal insufficiency in North America and hypertension in Africa and Latin America. Interpretation: Prevention and treatment strategies targeting these potentially modifiable risk factors or patients with risk factors, especially cardiovascular disorders, may reduce the incidence of CI-AKI and should be evaluated in future studies. Funding Statement: The study is supported by the Science and Technology Planning Project of Guangdong Province (grant no. 2014B070706010), the National Science Foundation of China (grant no. 81670339 and 81970311), and the Beijing Lisheng Cardiovascular Pilot Foundation (grant no. LHJJ201612127). Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: (PROSPERO register number: CRD42019121534).