The relationships between visit-to-visit blood pressure variability and renal and endothelial function in chronic kidney disease

Visit-to-visit blood pressure variability has been shown to be an independent risk factor for cardiovascular diseases. High visit-to-visit blood pressure variability and endothelial dysfunction are observed in patients with chronic kidney disease. It is therefore assumed that high variability in visit-to-visit blood pressure measurements may be associated with endothelial dysfunction in these patients. The present study investigated the associations between visit-to-visit blood pressure variability and renal and endothelial function in patients with chronic kidney disease. We analyzed 150 consecutive patients with predialysis chronic kidney disease who visited our outpatient clinic from January 2006 to December 2010. The study examined the relationships between variability in visit-to-visit systolic blood pressure levels or mean systolic blood pressure (M SBP) and estimated glomerular filtration rate (eGFR) and flow-mediated dilation, an index of endothelial function. Variability in visit-to-visit systolic blood pressure showed a significant negative association with eGFR, independent of age, hemoglobin A1c, low-density lipoprotein (LDL) cholesterol and uric acid, whereas M SBP did not. Similarly, variability in SBP showed a significant negative association with flow-mediated dilation, independent of age, eGFR, HbA1c, LDL cholesterol and M SBP. These data indicate that variability in visit-to-visit blood pressure measurements is associated with impaired renal and endothelial function in patients with chronic kidney disease. This finding suggests that reducing blood pressure fluctuations might have beneficial effects in patients with chronic kidney disease, although this point needs to be addressed by future studies.