Miaolin Che1, Xudong Wang2, Bo Xie2, Ritai Huang2, Shang Liu1, Yucheng Yan1, Mingli Zhu1, Renhua Lu1, Jiaqi Qian1, Weiming Zhang1, Leyi Gu1, Shan Mou1, Zhaohui Ni3, Song Xue2. 1. Department of Nephrology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China. 2. Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China. 3. Department of Nephrology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China, drnizhaohui@126.com.
Abstract
BACKGROUND/AIMS: Cardiac surgery-associated acute kidney injury (CSA-AKI) was traditionally defined as an increase in serum creatinine (sCr) after cardiac surgery. Recently, serum cystatin C (sCyC) has been proposed to be a better biomarker in the prediction of AKI. The clinical utility and performance of combining sCyC and sCr in patients with AKI, particularly for the prediction of long-term outcomes, remain unknown. METHODS: We measured sCyC together with sCr in 628 patients undergoing cardiac surgery. sCyC and sCr were assessed at baseline and 24 and 48 h after surgery. CSA-AKI determined by sCr (CSA-AKIsCr) was defined as an sCr increase greater than 0.3 mg/dL or 50% from baseline. Major adverse events (MAEs; including death of any cause and dialysis) at 3 years were assessed. RESULTS: CSA-AKIsCr developed in 178 patients (28.3%). Three-year follow-up was available for 621 patients; MAEs occurred in 42 patients (6.8%). An increase in sCyC concentration ≥30% within 48 h after surgery was detected in 228 patients (36.3%). This was the best sCyC cutoff for CSA-AKIsCr detection (negative predictive value = 88.8%, positive predictive value = 58.3%). To evaluate the use of both sCyC and sCr as CSA-AKI diagnostic criteria, we stratified patients into 3 groups: non-CSA-AKI, CSA-AKI detected by a single marker, and CSA-AKI detected by both markers. By multivariable logistic regression analysis, the independent predictors of MAEs at 3 years were group 2 (non-CSA-AKI group as the reference, CSA-AKI detected by a single marker: odds ratio [OR] = 3.48, 95% confidence interval [CI]: 1.27-9.58, p = 0.016), group 3 (CSA-AKI detected by both markers: OR = 5.12, 95% CI: 2.01-13.09; p = 0.001), and baseline glomerular filtration rate (OR = 2.24; 95% CI: 1.27-3.95; p = 0.005). CONCLUSION: Combining sCyC and sCr to diagnose CSA-AKI would be beneficial for risk stratification and prognosis in patients after cardiac surgery.
BACKGROUND/AIMS: Cardiac surgery-associated acute kidney injury (CSA-AKI) was traditionally defined as an increase in serum creatinine (sCr) after cardiac surgery. Recently, serum cystatin C (sCyC) has been proposed to be a better biomarker in the prediction of AKI. The clinical utility and performance of combining sCyC and sCr in patients with AKI, particularly for the prediction of long-term outcomes, remain unknown. METHODS: We measured sCyC together with sCr in 628 patients undergoing cardiac surgery. sCyC and sCr were assessed at baseline and 24 and 48 h after surgery. CSA-AKI determined by sCr (CSA-AKIsCr) was defined as an sCr increase greater than 0.3 mg/dL or 50% from baseline. Major adverse events (MAEs; including death of any cause and dialysis) at 3 years were assessed. RESULTS: CSA-AKIsCr developed in 178 patients (28.3%). Three-year follow-up was available for 621 patients; MAEs occurred in 42 patients (6.8%). An increase in sCyC concentration ≥30% within 48 h after surgery was detected in 228 patients (36.3%). This was the best sCyC cutoff for CSA-AKIsCr detection (negative predictive value = 88.8%, positive predictive value = 58.3%). To evaluate the use of both sCyC and sCr as CSA-AKI diagnostic criteria, we stratified patients into 3 groups: non-CSA-AKI, CSA-AKI detected by a single marker, and CSA-AKI detected by both markers. By multivariable logistic regression analysis, the independent predictors of MAEs at 3 years were group 2 (non-CSA-AKI group as the reference, CSA-AKI detected by a single marker: odds ratio [OR] = 3.48, 95% confidence interval [CI]: 1.27-9.58, p = 0.016), group 3 (CSA-AKI detected by both markers: OR = 5.12, 95% CI: 2.01-13.09; p = 0.001), and baseline glomerular filtration rate (OR = 2.24; 95% CI: 1.27-3.95; p = 0.005). CONCLUSION: Combining sCyC and sCr to diagnose CSA-AKI would be beneficial for risk stratification and prognosis in patients after cardiac surgery.