Serum angiotensinogen as a biomarker for renal outcomes in patients with acute myocardial infarction: prognostic significance and clinical implications

Acute kidney injury (AKI), also referred to as type 1 cardiorenal syndrome (CRS), is a frequent complication of acute myocardial infarction (AMI), with reported incidence rates in the literature ranging from 9.6% to 43.2%. Type 1 CRS has been shown to elevate the risk of chronic kidney disease (CKD) in affected patients, although the precise incidence of CKD in this context remains uncertain. Prior research has indicated that certain biomarkers, including angiotensinogen and α-Klotho, may facilitate the early identification of type 1 CRS. However, whether these emerging biomarkers possess predictive value for long-term renal outcomes in patients with AMI remains to be elucidated. This prospective observational study enrolled 149 patients with AMI from Shanghai Tongji Hospital between November 2018 and August 2019. Patients were categorized into two groups: those without acute kidney injury (non-AKI; n = 103) and those with acute kidney injury (AKI; n = 21). At admission, serum levels of angiotensinogen, α-Klotho, and fibroblast growth factor 23 (FGF-23) were measured using enzyme-linked immunosorbent assay (ELISA). The average follow-up duration was 36 months, during which the incidence of CKD among patients was monitored. The associations between the levels of these biomarkers and renal outcomes were subsequently analyzed. Among the 149 patients, 21 (14.09%) were diagnosed with AKI, with an in-hospital mortality rate of 0.02%. Over the 3-year follow-up period, 22 patients (17.60%) developed CKD. Only serum angiotensinogen levels are associated with the occurrence of AKI and CKD. We conducted an assessment of the predictive utility of three clinical models for the occurrence of AKI and CKD. The AUC for AKI and CKD diagnosis are 0.811 (95% CI: 0.565–0.733, p < 0.001), 0.700 (95% CI: 0.579–0.821, p < 0.001), respectively. The optimal cutoff value of serum angiotensinogen for AKI and CKD is 1541.40 and 1332.88 pg/ml, respectively. The inclusion of age, serum creatinine (Scr) and estimated glomerular filtration rate (eGFR) in the predictive models resulted in enhanced predictive efficacy. In conclusion, serum angiotensinogen levels emerge as a promising biomarker for predicting the development of AKI and CKD in patients with AMI.