title: Association of cardiac biomarkers with acute kidney injury after cardiac surgery: A multicenter cohort study.
abstract: OBJECTIVE
  Acute kidney injury is common after cardiac surgery and associated with postoperative mortality. Perioperative cardiac biomarkers may predict acute kidney injury and mortality. We evaluated whether cardiac biomarkers were associated with severe acute kidney injury, defined as a doubling in serum creatinine or requiring renal replacement therapy during hospital stay after surgery, and mortality.
  
  
  METHODS
  In a prospective multicenter cohort of adults undergoing cardiac surgery, we measured the following biomarkers in preoperative and postoperative banked plasma: high-sensitivity troponin T, cardiac troponin I, creatine kinase-MB, and N-terminal prohormone of brain natriuretic peptide.
  
  
  RESULTS
  In the patients who were discharged alive, severe acute kidney injury occurred in 37 of 960 (3.9%), and 43 of 960 (4.5%) died within 1 year of follow-up. N-terminal prohormone of brain natriuretic peptide was the only preoperative biomarker that was independently associated with severe acute kidney injury (with log transformation, adjusted odds ratio, 1.4; 95% confidence interval, 1.0-1.9). Biomarkers measured within 6 hours of surgery (day 1) were all associated with severe acute kidney injury. Preoperative N-terminal prohormone of brain natriuretic peptide was also independently associated with 1-year mortality (with log transformation, adjusted odds ratio, 1.7; 95% confidence interval, 1.2-2.2). Patients in the highest tertile for N-terminal prohormone of brain natriuretic peptide preoperatively (>1006.4 ng/L) had marked increases in their risk for 1-year mortality (adjusted odds ratio, 27.2; 95% confidence interval, 3.5-213.5). Day 1 N-terminal prohormone of brain natriuretic peptide was associated with mortality independently of change in serum creatinine from preoperative baseline.
  
  
  CONCLUSIONS
  Of the studied biomarkers, N-terminal prohormone of brain natriuretic peptide was the only preoperative biomarker independently associated with severe acute kidney injury and mortality. Early increases in postoperative cardiac biomarkers were associated with severe acute kidney injury after cardiac surgery. Future research should focus on whether interventions that lower N-terminal prohormone of brain natriuretic peptide can affect postoperative outcomes.
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Emilie P
authors.initials: EP
authors.lastname: Belley-Côté
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine and the Clinical Epidemiology Research Center Veterans Affairs Connecticut Healthcare System, West Haven, Conn.
authors.forename: Chirag R
authors.initials: CR
authors.lastname: Parikh
authors.affiliation: Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Colleen R
authors.initials: CR
authors.lastname: Shortt
authors.affiliation: Department of Internal Medicine, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Steven G
authors.initials: SG
authors.lastname: Coca
authors.affiliation: Division of Nephrology, Department of Medicine, University of Western Ontario, London, Canada; Department of Epidemiology and Biostatistics, University of Western Ontario, London, Canada; Institute for Clinical Evaluative Sciences, Ontario, Canada.
authors.forename: Amit X
authors.initials: AX
authors.lastname: Garg
authors.affiliation: Department of Medicine, McMaster University, Hamilton, Ontario, Canada; Population Health Research Institute, Hamilton, Ontario, Canada.
authors.forename: John W
authors.initials: JW
authors.lastname: Eikelboom
authors.affiliation: Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Peter
authors.initials: P
authors.lastname: Kavsak
authors.affiliation: Institute for Clinical Evaluative Sciences, Ontario, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: McArthur
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine and the Clinical Epidemiology Research Center Veterans Affairs Connecticut Healthcare System, West Haven, Conn.
authors.forename: Heather
authors.initials: H
authors.lastname: Thiessen-Philbrook
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada; Population Health Research Institute, Hamilton, Ontario, Canada; Department of Surgery, McMaster University, Hamilton, Ontario, Canada. Electronic address: Richard.Whitlock@phri.ca.
authors.forename: Richard P
authors.initials: RP
authors.lastname: Whitlock
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood* / Q000453:epidemiology / Q000209:etiology; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D052279:Creatine Kinase, MB Form / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006331:Heart Diseases / Q000601:surgery*; D006801:Humans; D015994:Incidence; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood; D009864:Ontario / Q000453:epidemiology; D010446:Peptide Fragments / Q000097:blood; D011183:Postoperative Complications; D011446:Prospective Studies; D019210:Troponin I / Q000097:blood; D020107:Troponin T / Q000097:blood; D014481:United States / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; D019210:Troponin I; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D052279:Creatine Kinase, MB Form
keywords: acute kidney injury; biomarkers; brain natriuretic peptide; cardiac surgery; mortality; troponin