Ckd epi equation

Serum creatinine is the most commonly measured endogenous filtration marker. It is a 113 dalton amino acid derivative that is generated from the breakdown of creatine in muscle, distributed throughout total body water, and excreted by the kidneys primarily by glomerular filtration. Although the serum level is affected primarily by the level of GFR, it is also affected by other physiological processes, such as tubular secretion, generation and extrarenal excretion of creatinine. Due to variation in these processes amongst individuals and over time within individuals over time, particularly the variation in creatinine generation, the cutoff for normal versus abnormal serum creatinine concentration differs among groups. Because of the wide range of normal for serum creatinine in most clinical laboratories, GFR must decline to approximately half the normal level before the serum creatinine concentration rises above the upper limit of normal. Therefore, the estimated GFR which combines the serum level with other demographic factors that represent these unmeasured physiological variables, provides more information that the serum creatinine alone. Three commonly used equations are the CKD-EPI creatinine equations, the Modification of Diet in Renal Disease (MDRD) Study equation, and Cockcroft and Gault equation. All three of these equations use serum creatinine in combination with age, sex, weight or race to estimate GFR and, therefore, improve upon several of the limitations with...

• The Recommended method for estimating GFR in adults from the National Kidney Foundation is the 2021 CKD-EPI equations. • Designed for use with laboratory creatinine values that are standardized to IDMS. (See "About GFR" button.) • Estimates GFR from serum creatinine, age and sex • More accurate than the MDRD Study equation, particularly in people with higher levels of GFR. • The CKD-EPI equation are modeled using least squares linear regression to relate log transformed measured GFR to log-transformed filtration markers, age and sex with two slope splines for creatinine • Some clinical laboratories are still reporting GFR estimates using the MDRD Study equation. The National Kidney Foundation has recommended that clinical laboratories should begin using the 2021 CKD-EPI equation to report estimated GFR using creatinine and cystatin C. • Levey AS, Stevens LA, Schmid CH, et al. A new equation to estimate glomerular filtration rate. Ann Intern Med. May 5 2009; 150(9): 604-612. • Levey AS, Stevens LA. Estimating GFR using the CKD Epidemiology Collaboration (CKD-EPI) creatinine equation: more accurate GFR estimates, lower CKD prevalence estimates, and better risk predictions. Am J Kidney Dis. Apr 2010; 55(4): 622-627. • Matsushita K, Selvin E, Bash LD, Astor BC, Coresh J. Risk implications of the new CKD Epidemiology Collaboration (CKD-EPI) equation compared with the MORD Study equation for estimated GFR: the Atherosclerosis Risk in Communities (ARIC) Study. Am J Kidney Dis. ...

The CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation was developed in an effort to create a more precise formula to estimate glomerular filtrate rate (GFR) from serum creatinine and other readily available clinical parameters, especially at when actual GFR is >60 mL/min per 1.73m 2. Researchers pooled data from multiple studies to develop and validate this new equation. They randomly divided 10 studies which included 8254 participants, into separate data sets for development and internal validation. 16 additional studies, which included 3896 participants, were used for external validation. The CKD-EPI equation performed better than the MDRD (Modification of Diet in Renal Disease Study) equation, especially at higher GFR, with less bias and greater accuracy. When looking at NHANES (National Health and Nutrition Examination Survey) data, the median estimated GFR was 94.5 mL/min per 1.73 m 2 vs. 85.0 mL/min per 1.73 m 2, and the prevalence of chronic kidney disease was 11.5% versus 13.1%. The CKD-EPI equation, expressed as a single equation, is: • GFR = 141 * min(Scr/κ,1) α * max(Scr/κ, 1) -1.209 * 0.993 Age * 1.018 [if female] * 1.159 [if black] Scr is serum creatinine (mg/dL), κ is 0.7 for females and 0.9 for males, α is -0.329 for females and -0.411 for males, min indicates the minimum of Scr/κ or 1, and max indicates the maximum of Scr/κ or 1. Lesley A. Inker, M.D., Nwamaka D. Eneanya, M.D., M.P.H., Josef Coresh, M.D., Ph.D., Hocine Tighiouart, M.S., D...