Factors involved in vascular calcification and atherosclerosis in maintenance haemodialysis patients.
BACKGROUND
Atherosclerosis and vascular calcifications are common causes of morbidity and mortality in maintenance haemodialysis patients. In addition to the well-known traditional risk factors, uraemia-specific factors appear to enhance dramatically the progression of the pathological processes involved. The aim of the present study was to evaluate the degree of atherosclerosis and vascular calcifications in chronic haemodialysis patients using non-invasive imaging methods, and to identify potentially involved factors.


METHODS
The study included 73 patients (36 females, 37 males), aged 25-75 years, who were on haemodialysis treatment for 12-275 months (mean dialysis vintage 73.8 months). We assessed the following circulating parameters: calcium (Ca), phosphorus, 'intact' parathyroid hormone (iPTH), 25OH vitamin D, lipids, oxidized LDL (ox-LDL), Lp(a), homocysteine, leptin, IL-1-beta, IL-6, CRP, TGF-beta, TNF-alpha, (PDGF), advanced oxidation protein products (AOPP) and myeloperoxidase activity (MPO). Coronary artery calcification score (CACS) was assessed using multi-row spiral CT (MSCT). Intima-media thickness index of the common carotid artery (CCA-IMT) and presence of cervical artery atherosclerotic plaques were evaluated by ultrasonography.


RESULTS
Coronary artery calcifications were observed in 79.5% of the patients, with CACS ranging from 0 to 4987. In univariate analysis, a positive correlation was observed between CACS and age, BMI, iPTH, CRP, IL-6 and CCA-IMT, whereas an inverse correlation existed with 25OH vitamin D, TGF-beta and PDGF. CCA-IMT ranged from 0.4 to 1.1 mm. It was positively correlated, in univariate analysis, with age, CACS, CRP and Il-6, and negatively with 25OH vitamin D, TGF-beta and PDGF. Only CACS remained as independent predictive factor of CCA-IMT in multivariate analysis. Atherosclerotic plaques were found in the carotid arteries of 53 patients (72%). The number of plaques was positively correlated with age, CACS, phosphorus, MPO, CRP and IL-6, and inversely with 25OH vitamin D in univariate analysis. In multivariate regression analysis, only age and CACS remained as independent variables.


CONCLUSIONS
In addition to classic risk factors, the degree of atherosclerosis and vascular calcification in our dialysis patient population were associated with several factors that are frequently abnormal in advanced chronic renal failure, but except age, all of them were interdependent. Notably, as in the general population, CACS was an independent predictor of the degree of atherosclerosis in haemodialysis patients.
Kraśniak
Andrzej
A
Department of Nephrology, Jagiellonian University, 31-501 Krakow, ul. Kopernika 15c, Poland.
Drozdz
Maciej
M
Pasowicz
Mieczysław
M
Chmiel
Grzegorz
G
Michałek
Martyna
M
Szumilak
Dorota
D
Podolec
Piotr
P
Klimeczek
Piotr
P
Konieczyńska
Małgorzata
M
Wicher-Muniak
Ewa
E
Tracz
Wiesława
W
Khoa
Thao N'guyen
TN
Souberbielle
Jean-Claude
JC
Drueke
Tilman B
TB
Sulowicz
Władysław
W
D000328:Adult; D000368:Aged; D050197:Atherosclerosis / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D015415:Biomarkers / Q000097:blood; D002114:Calcinosis / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging; D003327:Coronary Disease / Q000097:blood / Q000000981:diagnostic imaging / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D011379:Prognosis; D006435:Renal Dialysis / Q000009:adverse effects*; D012307:Risk Factors; D012720:Severity of Illness Index; D036542:Tomography, Spiral Computed; D018615:Ultrasonography, Doppler, Color
D015415:Biomarkers