title: Association of Preoperative Urinary Uromodulin with AKI after Cardiac Surgery.
abstract: AKI is a serious complication after cardiac surgery. Although high urinary concentrations of the tubular protein uromodulin, a marker of tubular health, are associated with less AKI in animal models, its relationship in humans is unknown.
  
  
  
  A post hoc analysis of a prospective cohort study of 218 adults undergoing on-pump cardiac surgery between 2004 and 2011 was conducted. Multivariable logistic and linear regression analyses were used to evaluate the associations of preoperative urinary uromodulin-to-creatinine ratio with postoperative AKI (defined as a rise in serum creatinine of >0.3 mg/dl or >1.5 times baseline); severe AKI (doubling of creatinine or need for dialysis) and peak postoperative serum creatinine over the first 72 hours.
  
  
  
  Mean age was 68 years, 27% were women, 95% were white, and the median uromodulin-to-creatinine ratio was 10.0 μg/g. AKI developed in 64 (29%) patients. Lower urinary uromodulin-to-creatinine ratio was associated with higher odds for AKI (odds ratio, 1.49 per 1-SD lower uromodulin; 95% confidence interval, 1.04 to 2.13), which was marginally attenuated after multivariable adjustment (odds ratio, 1.43; 95% confidence interval, 0.99 to 2.07). The lowest uromodulin-to-creatinine ratio quartile was also associated with higher odds for AKI relative to the highest quartile (odds ratio, 2.94; 95% confidence interval, 1.19 to 7.26), which was slightly attenuated after multivariable adjustment (odds ratio, 2.43; 95% confidence interval, 0.91 to 6.48). A uromodulin-to-creatinine ratio below the median was associated with higher adjusted odds for severe AKI, although this did not reach statistical significance (odds ratio, 4.03; 95% confidence interval, 0.87 to 18.70). Each 1-SD lower uromodulin-to-creatinine ratio was associated with a higher adjusted mean peak serum creatinine (0.07 mg/dl per SD; 95% confidence interval, 0.02 to 0.13).
  
  
  
  Lower uromodulin-to-creatinine ratio is associated with higher odds of AKI and higher peak serum creatinine after cardiac surgery. Additional studies are needed to confirm these preliminary results.
authors: Division of Nephrology and.
authors: Pranav S
authors: PS
authors: Garimella
authors: Department of Medicine, St. Elizabeth's Medical Center, Boston, Massachusetts.
authors: Bertrand L
authors: BL
authors: Jaber
authors: The Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, Massachusetts.|Tufts Clinical and Translational Science Institute, Tufts University, Boston, Massachusetts.
authors: Hocine
authors: H
authors: Tighiouart
authors: Division of Nephrology and Hypertension, III Medizinische Klinik, Klinikum Coburg, Coburg, Germany.
authors: Orfeas
authors: O
authors: Liangos
authors: Division of Nephrology and Hypertension, University of Cincinnati, Cincinnati, Ohio; and.
authors: Michael R
authors: MR
authors: Bennett
authors: Division of Nephrology and Hypertension, University of Cincinnati, Cincinnati, Ohio; and.
authors: Prasad
authors: P
authors: Devarajan
authors: Division of Nephrology, Roudebush Indianapolis Veterans Affairs Medical Center, Indianapolis, Indiana.
authors: Tarek M
authors: TM
authors: El-Achkar
authors: Division of Nephrology and.
authors: Mark J
authors: MJ
authors: Sarnak
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology / Q000652:urine*; D000368:Aged; D000369:Aged, 80 and over; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D003404:Creatinine / Q000097:blood / Q000652:urine*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology / Q000652:urine*; D057234:Preoperative Period; D011446:Prospective Studies; D012307:Risk Factors; D058949:Uromodulin / Q000652:urine*
chemical_list: D058949:Uromodulin; D003404:Creatinine
keywords: Animals; Cardiac Surgical Procedures; Cohort Studies; Female; Humans; Kidney Function Tests; Models, Animal; Odds Ratio; Postoperative Period; Prospective Studies; Regression Analysis; Uromodulin; acute kidney injury; adult; cardiac surgery; creatinine; renal dialysis; tubular function; uromodulin