Factors associated with various arterial calcifications in haemodialysis patients

Haemodialysis (HD) patients are at increased risk of the development of arterial intimal (AIC) and medial calcification (AMC). The aim of our study was to analyze the association between the pre-defined potential risk factors and the status of various arterial calcifications in our HD patients.

In a cross-sectional study of 150 patients (91 male, mean age 54.55 +/- 12.46 yrs, HD duration 104.77 +/- 68.02 mths) we first determined the presence of AIC and AMC using plain radiography of the pelvis. We then compared the percentages of different radiogram findings in patients stratified according to various cut-off levels or the codes of each clinical and biochemical parameter (mean value of one year laboratory data recorded in the files).

We determined arterial calcifications in 77.3% of our patients (AIC in 45.3%, AMC in 32%). The significantly higher frequencies of arterial calcifications of both groups (AIC and/or AMC) and isolated AIC presence were found in patients older than 55 at inclusion and 45 at the start of treatment with HD, with a serum C-reactive protein (CRP) > 4.5 mg/L, predominantly of male gender with diabetes. The patients with a significantly higher occurrence of arterial calcifications had lower percentages of total serum calcium (Ca) levels but within the K/DOQI guideline recommendations. Also, we found a significantly higher proportion of isolated AIC presence in the group of patients with corrected total serum Ca levels > 2.35 mmol/L and serum intact parathyroid hormone (iPTH) levels out of the range proposed by K/DOQI guidelines. In parallel, a significantly higher percentage of absence of arterial calcifications (ACA) was obtained in the patients with corrected total serum Ca levels < 2.35 mmol/L, body mass index (BMI) < 23 kg/m(2), mean pulse pressure < 60 mmHg, blood leucocytes < 6.5 x 10(9)L and serum triglycerides < 1.8 mmol/L. Finally, we found a significantly higher presence of isolated AMC in patients with mean Kt/V < 1.3 (poor dialysis adequacy), serum triglycerides > 1.8 mmol/L and outside K/DOQI guideline achievements for corrected total serum Ca. In the 12 month period data analyzed, there were no significant differences in other risk factors such as the dose of prescribed calcium carbonate and vitamin D3, serum levels of albumin, cholesterol, phosphate (P) and Ca x P product.

AIC and AMC were frequently present in our HD population. Age, gender, BMI, diabetes, pulse pressure, dialysis adequacy, serum CRP, triglycerides, Ca and iPTH, as well as blood leucocyte levels were associated with the occurrence of arterial calcifications in our HD patients.