A systematic review and metaanalysis comparing the bias and accuracy of the Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration equations in community-based populations

Journal article

Background

The majority of patients with chronic kidney disease are diagnosed and monitored in primary care. Glomerular filtration rate (GFR) is a key marker of renal function, but direct measurement is invasive; in routine practice, equations are used for estimated GFR (eGFR) from serum creatinine. We systematically assessed bias and accuracy of commonly used eGFR equations in populations relevant to primary care.

Content

MEDLINE, EMBASE and the Cochrane Library were searched for studies comparing measured GFR (mGFR) with eGFR in adult populations comparable to primary care and reporting both the Modification of Diet in Renal Disease (MDRD) and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations based on standardised creatinine measurements. We pooled data on mean bias (difference between eGFR and mGFR) and on mean accuracy (proportion of eGFR within 30% of mGFR) using a random-effects inverse-variance weighted meta-analysis. We included 48 studies of 26,875 patients that reported data on bias and/or accuracy. Meta-analysis of within-study comparisons where both formulae were tested on the same patient cohorts using isotope dilution-mass spectrometry-traceable creatinine showed a lower mean bias in eGFR using CKD-EPI of 2.2 ml/min/1.73m2 (95% CI 1.1 to 3.2; 30 studies; I2=74.4%) and a higher mean accuracy of CKD-EPI of 2.7% (1.6 to 3.8; 47 studies; I2=55.5%). Meta-regression showed that in both equations bias and accuracy favoured the CKD-EPI equation at higher mGFR values.

Summary

Both equations underestimated mGFR but CKD-EPI gave more accurate estimates of GFR.

Authors: McFadden, E; Hirst, J; Verbakel, J; McLellan, J; Hobbs, F

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Association for Clinical Chemistry
• Journal: Clinical Chemistry
• Volume: 63
• Issue: 4
• Pages: 475–485
• Publication date: 2018-02-28
• Acceptance date: 2017-09-19
• DOI: 10.1373/clinchem.2017.276683
• EISSN: 1530-8561
• ISSN: 0009-9147
• Language: English
• Keywords: chronic kidney disease; glomerular filtration rate; CKD-EPI; MDRD