TY - JOUR
T1 - Presurgical serum cystatin C and risk of acute kidney injury after cardiac surgery
AU - Shlipak, Michael G.
AU - Coca, Steven G.
AU - Wang, Zhu
AU - Devarajan, Prasad
AU - Koyner, Jay L.
AU - Patel, Uptal D.
AU - Thiessen-Philbrook, Heather
AU - Garg, Amit X.
AU - Parikh, Chirag R.
N1 - Funding Information:
Support: The research reported in this article was supported by the American Heart Association Clinical Development award and grant RO1HL-085757 from the National Heart, Lung, and Blood Institute . The study was also supported by Clinical Translational Science Award grant number UL1 RR024139 from the National Center for Research Resources . The granting agencies did not participate in the protocol development, analysis, and interpretation of the results.
Funding Information:
The TRIBE-AKI (Translational Research Investigating Biomarker Endpoints in Acute Kidney Injury) Study is an investigator-initiated study that was funded by the National Heart, Lung, and Blood Institute. The primary objective of this study is to investigate novel biomarkers for the early detection of AKI. A second aim of the study is to identify novel presurgical biomarkers for AKI, with cystatin C having been proposed as the leading candidate. We conducted a prospective cohort study of adults undergoing cardiac surgery (coronary artery bypass grafting [CABG], surgery for valve disease, and both) at 6 academic medical centers in North America between July 2007 and December 2009. Median time between the presurgical visit and cardiac surgery was 4.6 (25th-75th percentile, 1.6-11.5) days; 1,087 (95%) presurgical visits occurred within 30 days, and only 2 patients had visits more than 90 days before surgery (367 and 371 days before surgery). All patients were at high risk of AKI, defined as the presence of 1 or more of the following criteria: pre-existing renal impairment (baseline serum creatinine >2 mg/dL [>177 μmol/L]), ejection fraction 4.5 mg/dL (>400 μmol/L), or end-stage renal disease. All participants provided written informed consent, and the study was approved by each institution's research ethics board. This clinical study has been registered at Clinicaltrials.gov as NCT00774137 .
PY - 2011/9
Y1 - 2011/9
N2 - Background: Acute kidney injury (AKI) after cardiac surgery is associated with poor outcomes, but is challenging to predict from information available before surgery. Study Design: Prospective cohort study. Setting & Participants: The TRIBE-AKI (Translational Research Investigating Biomarker Endpoints in Acute Kidney Injury) Consortium enrolled 1,147 adults undergoing cardiac surgery at 6 hospitals from 2007-2009; participants were selected for high AKI risk. Predictors: Presurgical values for cystatin C, creatinine, and creatinine-based estimated glomerular filtration rate (eGFR) were categorized into quintiles and grouped as "best" (quintiles 1-2), "intermediate" (quintiles 3-4), and "worst" (quintile 5) kidney function. Outcomes: The primary outcome was AKI Network (AKIN) stage 1 or higher; <0.3 mg/dL or 50% increase in creatinine level. Measurements: Analyses were adjusted for characteristics used clinically for presurgical risk stratification. Results: Average age was 71 ± 10 years (mean ± standard deviation); serum creatinine, 1.1 ± 0.3 mg/dL; eGFR-Cr, 74 ± 9 mL/min/1.73 m2; and cystatin C, 0.9 ± 0.3 mg/L. 407 (36%) participants developed AKI during hospitalization. Adjusted odds ratios for intermediate and worst kidney function by cystatin C were 1.9 (95% CI, 1.4-2.7) and 4.8 (95% CI, 2.9-7.7) compared with 1.2 (95% CI, 0.9-1.7) and 1.8 (95% CI, 1.2-2.6) for creatinine and 1.0 (95% CI, 0.7-1.4) and 1.7 (95% CI, 1.1-2.3) for eGFR-Cr categories, respectively. After adjustment for clinical predictors, the C statistic to predict AKI was 0.70 without kidney markers, 0.69 with creatinine, and 0.72 with cystatin C. Cystatin C also substantially improved AKI risk classification compared with creatinine, based on a net reclassification index of 0.21 (P < 0.001). Limitations: The ability of these kidney biomarkers to predict risk of dialysis-requiring AKI or death could not be assessed reliably in our study because of a small number of patients with either outcome. Conclusions: Presurgical cystatin C is better than creatinine or creatinine-based eGFR at forecasting the risk of AKI after cardiac surgery.
AB - Background: Acute kidney injury (AKI) after cardiac surgery is associated with poor outcomes, but is challenging to predict from information available before surgery. Study Design: Prospective cohort study. Setting & Participants: The TRIBE-AKI (Translational Research Investigating Biomarker Endpoints in Acute Kidney Injury) Consortium enrolled 1,147 adults undergoing cardiac surgery at 6 hospitals from 2007-2009; participants were selected for high AKI risk. Predictors: Presurgical values for cystatin C, creatinine, and creatinine-based estimated glomerular filtration rate (eGFR) were categorized into quintiles and grouped as "best" (quintiles 1-2), "intermediate" (quintiles 3-4), and "worst" (quintile 5) kidney function. Outcomes: The primary outcome was AKI Network (AKIN) stage 1 or higher; <0.3 mg/dL or 50% increase in creatinine level. Measurements: Analyses were adjusted for characteristics used clinically for presurgical risk stratification. Results: Average age was 71 ± 10 years (mean ± standard deviation); serum creatinine, 1.1 ± 0.3 mg/dL; eGFR-Cr, 74 ± 9 mL/min/1.73 m2; and cystatin C, 0.9 ± 0.3 mg/L. 407 (36%) participants developed AKI during hospitalization. Adjusted odds ratios for intermediate and worst kidney function by cystatin C were 1.9 (95% CI, 1.4-2.7) and 4.8 (95% CI, 2.9-7.7) compared with 1.2 (95% CI, 0.9-1.7) and 1.8 (95% CI, 1.2-2.6) for creatinine and 1.0 (95% CI, 0.7-1.4) and 1.7 (95% CI, 1.1-2.3) for eGFR-Cr categories, respectively. After adjustment for clinical predictors, the C statistic to predict AKI was 0.70 without kidney markers, 0.69 with creatinine, and 0.72 with cystatin C. Cystatin C also substantially improved AKI risk classification compared with creatinine, based on a net reclassification index of 0.21 (P < 0.001). Limitations: The ability of these kidney biomarkers to predict risk of dialysis-requiring AKI or death could not be assessed reliably in our study because of a small number of patients with either outcome. Conclusions: Presurgical cystatin C is better than creatinine or creatinine-based eGFR at forecasting the risk of AKI after cardiac surgery.
KW - Acute renal failure
KW - creatinine
KW - prognosis
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U2 - 10.1053/j.ajkd.2011.03.015
DO - 10.1053/j.ajkd.2011.03.015
M3 - Article
C2 - 21601336
AN - SCOPUS:80051941015
SN - 0272-6386
VL - 58
SP - 366
EP - 373
JO - American Journal of Kidney Diseases
JF - American Journal of Kidney Diseases
IS - 3
ER -