Performance of creatinine-based GFR estimating equations in solid-organ transplant recipients.
BACKGROUND
Accurate assessment of kidney function is important for the management of solid-organ transplant recipients. In other clinical populations, glomerular filtration rate (GFR) most commonly is estimated using the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) creatinine or the 4-variable MDRD (Modification of Diet in Renal Disease) Study equation. The accuracy of these equations compared with other GFR estimating equations in transplant recipients has not been carefully studied.


METHODS
Diagnostic test study.


METHODS
Solid-organ transplant recipients longer than 6 months posttransplantation from 5 clinical populations (N=3,622, including recipients of kidney [53%], liver [35%], and other or multiple organs [12%]).


METHODS
Estimated GFR (eGFR) using creatinine-based GFR estimating equations identified from a systematic review of the literature. Performance of the CKD-EPI creatinine and the MDRD Study equations was compared with alternative equations.


METHODS
Measured GFR (mGFR) from urinary clearance of iothalamate or plasma clearance of iohexol.


METHODS
Error (difference between mGFR and eGFR) expressed as P30 (proportion of absolute percent error <30%) and mean absolute error.


RESULTS
We identified 26 GFR estimating equations. Mean mGFR was 55.1±22.7 (SD) mL/min/1.73 m(2). P30 and mean absolute error for the CKD-EPI and the MDRD Study equations were 78.9% (99.6% CI, 76.9%-80.8%) for both and 10.6 (99.6% CI, 10.1-11.1) versus 11.0 (99.6% CI, 10.5-11.5) mL/min/1.73 m(2), respectively; these equations were more accurate than any of the alternative equations (P <0.001 for all pairwise comparisons for both measures). They performed better than or as well as the alternative equations in most subgroups defined by demographic and clinical characteristics, including type of transplanted organ.


CONCLUSIONS
Study population included few nonwhites and people with solid-organ transplants other than liver and kidneys.


CONCLUSIONS
The CKD-EPI creatinine and the MDRD Study equations perform better than the alternative creatinine-based estimating equations in solid-organ transplant recipients. They can be used for clinical management.
Division of Nephrology, Department of Medicine, University of New Mexico, Albuquerque, NM.
Kamran
K
Shaffi
William B. Schwartz Division of Nephrology, Department of Medicine, Tufts Medical Center, Boston, MA.
Katrin
K
Uhlig
William B. Schwartz Division of Nephrology, Department of Medicine, Tufts Medical Center, Boston, MA.
Ronald D
RD
Perrone
Research Design Center/Biostatistics Research Center, Tufts Clinical and Translational Science Institute, Tufts University, Boston, MA.
Robin
R
Ruthazer
Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN.
Andrew
A
Rule
Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN.
John C
JC
Lieske
Division of Nephrology, Department of Medicine, University Medical Center Groningen, Groningen, the Netherlands.
Gerjan
G
Navis
Department of Nephrology and Hypertension, Cleveland Clinic, Cleveland, OH.
Emilio D
ED
Poggio
William B. Schwartz Division of Nephrology, Department of Medicine, Tufts Medical Center, Boston, MA.
Lesley A
LA
Inker
William B. Schwartz Division of Nephrology, Department of Medicine, Tufts Medical Center, Boston, MA. Electronic address: alevey@tuftsmedicalcenter.org.
Andrew S
AS
Levey
D000328:Adult; D000368:Aged; D003404:Creatinine / Q000097:blood; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D007674:Kidney Diseases / Q000503:physiopathology*; D007677:Kidney Function Tests / Q000379:methods*; D008107:Liver Diseases / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D016377:Organ Transplantation; D015203:Reproducibility of Results
D003404:Creatinine
Glomerular filtration rate (GFR) estimation; creatinine-based estimated glomerular filtration rate (eGFR) equation; kidney transplantation; renal function; solid-organ transplant recipient