The prevalence of vascular calcification in patients with end-stage renal disease on hemodialysis: a cross-sectional observational study

Background: This multicenter international cross- sectional observational study characterized vascular and valvular calcification burden and correlations with pulse pressure, diabetes, hypertension, and cardiovascular diseases in prevalent hemodialysis patients. Methods: We enrolled 275 consecutive adults with end- stage renal disease on maintenance hemodialysis for >= 3 months. Coprimary endpoints were prevalences of: (1) echocardiographic calcification in mitral valve, aortic valve or mitral annulus; (2) aortoiliac tree vascular calcifications by plain lateral lumbar X- ray. Correlations among calcification sites and with demographics and comorbidities were determined. Pulse pressures were determined. Results: Subjects' mean +/- standard deviation (SD) age was 56 +/- 15.9 years; mean (SD) dialysis duration was 4.5 +/- 4.3 years. Overall, 100% of echocardiographically imaged patients (n = 243) had calcification in aortic valve, mitral valve, or mitral annulus; 77.8% of X- rayed patients (n = 248) had abdominal aortic calcification. Radiographic abdominal aortic calcification score correlated significantly with calcification of aortic valve (p < 0.0001) and mitral annulus (p = 0.0001) but not mitral valve. Aortic valve, mitral valve, and mitral annulus calcification correlated significantly among themselves (p < 0.0001). Moderate/severe aortic valve calcification was significantly more prevalent in patients aged >= 65 years than < 65 years, men than women, and Whites than African Americans. Pulse pressure correlated significantly with vascular calcification score (p = 0.0049) but not with valvular calcification at any site. Conclusions: Vascular and valvular calcification are highly prevalent in the hemodialysis population. Peripheral vascular calcification correlates significantly with elevated pulse pressure and can be assessed easily using lateral lumbar X-ray. Further studies investigating the interaction between pulse pressure and development or progression of vascular calcification are of interest.