Barr ELM

Maple-Brown, Louise

Barzi F

Hughes Wagadagam , Jaquelyne

Jerums G

Ekinci EI

Jones GRD

Ellis AG

Lawton, P

Sajiv, Cherian

Majoni, Sandawana William

Brown ADH

Hoy WE

O'Dea K

Cass A

MacIsaac RJ

2017-04-01

The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation that combines creatinine and cystatin C is superior to equations that include either measure alone in estimating glomerular filtration rate (GFR). However, whether cystatin C can provide any additional benefits in estimating GFR for Indigenous Australians, a population at high risk of end-stage kidney disease (ESKD) is unknown. Using a cross-sectional analysis from the eGFR Study of 654 Indigenous Australians at high risk of ESKD, eGFR was calculated using the CKD-EPI equations for serum creatinine (eGFRcr), cystatin C (eGFRcysC) and combined creatinine and cystatin C (eGFRcysC+cr). Reference GFR (mGFR) was determined using a non-isotopic iohexol plasma disappearance technique over 4h. Performance of each equation to mGFR was assessed by calculating bias, % bias, precision and accuracy for the total population, and according to age, sex, kidney disease, diabetes, obesity and c-reactive protein. Data were available for 542 participants (38% men, mean [sd] age 45 [14] years). Bias was significantly greater for eGFRcysC (15.0mL/min/1.73m2; 95% CI 13.3-16.4, p<0.001) and eGFRcysC+cr (10.3; 8.8-11.5, p<0.001) compared to eGFRcr (5.4; 3.0-7.2). Accuracy was lower for eGFRcysC (80.3%; 76.7-83.5, p<0.001) but not for eGFRcysC+cr (91.9; 89.3-94.0, p=0.29) compared to eGFRcr (90.0; 87.2-92.4). Precision was comparable for all equations. The performance of eGFRcysC deteriorated across increasing levels of c-reactive protein. Cystatin C based eGFR equations may not perform well in populations with high levels of chronic inflammation. CKD-EPI eGFR based on serum creatinine remains the preferred equation in Indigenous Australians.

Clin Biochem . 2017 Apr;50(6):301-308. doi: 10.1016/j.clinbiochem.2016.11.024. Epub 2016 Nov 25.

https://pubmed.ncbi.nlm.nih.gov/27894952/?otool=iaurydwlib

https://hdl.handle.net/10137/5306

CKD-EPI equation

Creatinine

Cystatin C

GFR

Indigenous

Adolescent

Adult

Algorithms

Australia

C-Reactive Protein

Creatinine

Cross-Sectional Studies

Cystatin C

Female

Humans

Kidney Function Tests

Male

Middle Aged

Population Groups

Renal Insufficiency, Chronic

Young Adult

Glomerular Filtration Rate

Comparison of creatinine and cystatin C based eGFR in the estimation of glomerular filtration rate in Indigenous Australians: The eGFR Study.

Journal Article

Publication