Estimated GFR is biased by non-traditional cardiovascular risk factors
AuthorMelsom, Toralf; Fuskevåg, Ole-Martin; Mathisen, Ulla Dorte; Strand, Harald; Schei, Jørgen; Jenssen, Trond Geir; Solbu, Marit Dahl; Eriksen, Bjørn Odvar
Methods: GFR was measured via iohexol clearance in a cross-sectional study of 1,624 middle-aged persons from the general population without CVD, diabetes or chronic kidney disease. The dimethylarginines were measured using liquid chromatography tandem mass spectrometry (LC-MSMS). Insulin resistance was determined by the homeostasis model assessment (HOMA-IR).
Results: Asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), the L-arginine/ADMA ratio, and insulin resistance were associated with creatinine-based eGFR after accounting for measured GFR in multivariable adjusted analyses. The cystatin C-based eGFR showed a similar residual association with SDMA; an oppositely directed, borderline significant association with ADMA; and a stronger residual association with insulin resistance compared with eGFR based on creatinine.
Conclusion: Both creatinine- and cystatin C-based eGFR are influenced by non-traditional risk factors, which may bias risk prediction by eGFR in longitudinal studies.