A Cystatin C-based glomerular filtration rate equation is a stronger predictor of cardiovascular mortality compared to creatinine-based equations

• Background: Several prior studies report that decreased estimated glomerular filtration rate (eGFR) predicts cardiovascular disease in the general population, but this is less studied in a primary preventive setting. Currently, various methods are available to assess eGFR. In the present study, we aimed to evaluate different eGFR-equations (creatinine-based or cystatin C-based), for the prediction of cardiovascular death. Material and methods: In men without cardiovascular disease, participating in the community-based Uppsala Longitudinal Study of Adult Men (ULSAM, n=649, mean age 71 years, median follow-up 12.9 years; 86 cardiovascular deaths during follow-up), eGFR was calculated from circulating creatinine by using the Modification of Diet in Renal Disease formula (eGFRMDRD) and the Chronic Kidney Disease Epidemiology Collaboration formula (eGFRCKD-EPI) and from circulating cystatin C using the following formula: 77.24x-1.2623 (eGFRcyst). Results: In Cox-proportional hazard models, 1-SD increase in eGFRcyst was associated with lower risk of cardiovascular mortality after adjustment for established cardiovascular risk factors and urinary albumin excretion rate (hazard ratio 0.74, 95% CI 0.59-0.92 (p=0.007). However, the creatinine-based GFR equations were not significantly associated with cardiovascular death (for eGFRMDRD: hazard ratio 0.84, 95% CI 0.67-1.06, (p=0.14), for eGFRCKD-EP : hazard ratio 0.86, 95% CI 0.69-1.07 (p=0.17)) in multivariable models. Moreover, when eGFRcyst was incorporated to a model with established risk factors, the integrated discrimination improvement was significantly increased 0.015, (p=0.02). Also eGFRcyst, provided improved discrimination beyond established risk factors and urinary albumine excretion rate (0.012, p=0.03). No improvement in integrated discrimination were seen with eGFRMDRD (p=0.25) or eGFRCKD-EPI (p=0.36). Conclusion: In our community-based cohort of elderly men free from cardiovascular disease at baseline, eGFRcyst significantly predicted cardiovascular death while the creatinine-based eGFR-equations did not. The fact that eGFRcyst improved model discrimination beyond established cardiovascular risk factors suggest that it may be a relevant risk marker for cardiovascular death in the elderly.

Keyword

Cystatin C

Glomerular filtration rate

cardiovascular mortality

Nedsatt njurfunktion, insulinresistens, oxidativ stress och utvecklingen av hjärt-kärlsjukdomar

Publication and Content Type

vet (subject category)

kon (subject category)