Do trace elements play a role in coronary artery calcification in hemodialysis patients?

Abnormalities of trace elements have previously been linked to inflammatory processes in hemodialysis (HD) patients. We aimed to establish the trace element status of maintenance HD patients, to investigate the relationship between coronary artery calcification scores (CACs) and whole blood levels of trace elements.

Patients undergoing HD in three times a week for > 6 months and age-and sex-matched controls were included from October 2015 to June 2016. Data were collected from patient files. All subjects' whole blood levels of trace elements were measured by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). CACs for patients were assessed by multi-detector computed tomography.

The 35 patients (male, 60%) with a mean age of 45.7 ± 10.4 years and 35 controls were included. HD patients showed significantly lower levels of selenium and uranium and higher cadmium (Cd), cobalt, lithium, manganese, nickel, lead, platinum, tin, strontium, and thallium levels compared to controls. Coronary artery calcification (CAC) was present in 21 patients (60%), and median CACs were 14.2 (IQR 0-149). Patients with CACs > median were significantly older, had a higher prevalence of hypertension and lower ALP levels than patients with CACs ≤ median. No significant differences in whole blood levels of trace elements were found between patients with CACs > median and patients with CACs ≤ median. A near significance was noted in median whole blood levels of Cd between these groups (P = 0.096). According to multivariate analysis, age was the only independent determinant for CAC development.

Age is independently associated with coronary vascular calcification. High Cd levels might play a role in CAC development in HD patients.