Association of central blood pressure with markers for target organ damage in chronic kidney disease patients : comparison between central and peripheral blood pressure

Abstract

Background Hypertension (HTN) is an established cardiovascular risk factor and is closely related with mortality in chronic kidney disease (CKD) patients. Recent studies demonstrated central blood pressure (CBP) was a significant predictor of cardiovascular disease (CVD) and had stronger relationship with vascular damage such as vascular calcification and stiffness than peripheral blood pressure (PBP). Therefore, we investigated the association of CBP or PBP with markers for target organ damage measured by pulse wave velocity (PWV) and coronary calcium score (CCS) in CKD patients including end-stage renal disease (ESRD) patients.

Method Patients enrolled by Cardiovascular and Metabolic Disease Etiology Research center (CMERC) of Yonsei University College of Medicine between November 2013 and May 2015 were eligible in this study. We analyzed the associations between central or peripheral blood pressure values (systolic blood pressure and pulse pressure) and parameters for target organ damage measured by PWV and CCS in CKD patients.

Result Among a total of 424 CKD patients, 248 (58.4%) were male and mean age was 59±12.4 years. Mean central systolic blood pressure (SBP) and pulse pressure (PP) were 132.7 and 54.8 mmHg and mean peripheral SBP and PP were 135.7 and 58.2 mmHg in study patients. The central SBP and PP were significantly higher in patients with advanced CKD stage compared to those in less advanced CKD patients. There were significant correlations between central or peripheral SBP and markers for target organ damage (PWV; r = 0.424 vs 0.361 and CCS; 0.262 vs 0.196, all p < 0.001). The associations of central SBP with presented markers for target organ damage were significantly stronger than peripheral SBP in total CKD patients (PWV; Z = 2.050, P = 0.040 and CCS; Z = 2.010, P = 0.044). When we evaluated the associations between blood pressure values and markers according to CKD stage, central SBP was more closely correlated with markers for target organ damage compared to peripheral SBP in early CKD population. However, present study did not show better association of CBP with markers for target organ damage compared to PBP in ESRD patients.

Conclusion Central SBP and PP are significantly associated with markers for target organ damage in CKD patients. In addition, central SBP has stronger associations with CCS and PWV compared to peripheral SBP in non-dialysis CKD patients. However, CBP is not superior to PBP for predicting target organ damage in ESRD patients.