Relationship between Arterial Stiffness and Renal Function Determined by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) Equations in a Chinese Cohort Undergoing Health Examination

Abstract

Background. The association between arterial stiffness and cardiovascular risk in CKD and ESRD patients is well established. However, the relationship between renal function estimation and properties of large arteries is unclear due to the four different methods used to quantify glomerular filtration. This study investigated the relationship between carotid-femoral pulse wave velocity (c-fPWV), as a measure of arterial stiffness, and accepted metrics of renal function. Methods. This cross-sectional study was conducted in 431 health examination individuals in China, enrolled from January 2017 to June 2019. c-fPWV and blood pressure were measured, and blood samples were obtained for all participants. Four different methods were used to determine the estimated glomerular filtration rate (eGFR) as described by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) equations: (i) CKD-EPISCr formula based on SCr, (ii) CKD-EPICysC formula based on CysC, (iii) CKD-EPISCr/CysC formula based on Cr and CysC, and (iv) MDRD. Results. Of all of the study participants (average age $53.1\pm 13.0$ years, 68.1% male), 23.7% had diabetes mellitus and 66.6% had hypertension. The average eGFR values determined by the CKD-EPISCr, CKD-EPICysC, CKD-EPISCr/CysC, and MDRD equations were $91.9\pm 15.6$ , $86.8\pm 21.4$ , $89.6\pm 18.3$ , and $90.7\pm 16.6$  ml/min/1.73m2, respectively. c-fPWV was significantly and negatively correlated with eGFR determined by CKD-EPISCr ( $r=-0.336$ , $P<0.001$ ), CKD-EPICysC ( $r=-0.385$ , $P<0.001$ ), CKD-EPISCr/CysC ( $r=-0.378$ , $P<0.001$ ), and MDRD ( $r=-0.219$ , $P<.001$ ) equations. After adjusting for confounding factors, c-fPWV remained significantly and negatively correlated with eGFR determined by the CKD-EPICysC equation ( $\beta =-0.105$ , $P=0.042$ ) and significantly and positively correlated with age ( $\beta =0.349$ , $P\le 0.01$ ), systolic pressure ( $\beta =0.276$ , $P\le 0.01$ ), and hypoglycemic drugs ( $\beta =0.101$ , $P=0.019$ ). Conclusion. In a health examination population in China, c-fPWV is negatively correlated with eGFR determined by four different equations; however, only the metric of eGFR determined by the equation for CKD-EPICysC showed an independent relation with c-fPWV.