Effect of blood selenium on left ventricular structure and function in maintenance hemodialysis patients

Objective To explore the effect of blood selenium on left ventricular structure and function in maintenance hemodialysis (MHD) patients and its possible mechanism. Methods Blood selenium, thyroid hormone(TH), parathyroid hormone (PTH) and oxidative stress indicators were measured by mass spectrometry, radioimmunoassay, chemiluminescence and biochemical colorimetry in 40 MHD patients, 40 non-dialysis patients with chronic renal failure (NOHD) and 30 normal controls respectively. Philips CX50 color ultrasound was used to measure left ventricular diameter (LVD), left atrial diameter (LAD), left ventricular end diastolic diameter (LVDd), left ventricular posterior wall thickness (LVPWT), interventricular septal thickness (IVST) and left ventricular ejection fraction (LVEF). Left ventricular mass index (LVMI) was calculated according to Devereux formula. The relationship between blood selenium and other parameters and its influence on the structure and function of the left ventricle were analyzed. Results The serum selenium,TT₃ and FT₃ in patients with MHD were lower than that of the normal control group (P<0.01).The content of serum PTH in patients with MHD was higher than that of the normal control group (P<0.01).The serum superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) activities in patients with MHD were lower than those in normal control group (P<0.01), while malondialdehyde (MDA) was higher than that in normal control group (P< 0.01). CRP content was higher than that in the normal control group (P<0.01). LAD, LVDd and LVMI in MHD patients were higher than those in normal control group (P<0.01). Bivariate correlation analysis showed that, in MHD patients, there was a positive correlation between serum selenium and GSH-Px, SOD,TT₃ and FT₃ (P<0.05); and negative correlation with CRP, MDA, LAD and LVDd (P<0.05).GSH-Px was negatively correlated with LAD, LVDd, IVST and LVMI (P<0.05); SOD was negatively correlated with LAD, IVST and LVMI (P<0.05); and MDA was positively correlated with LAD, LVDd, IVST and LVMI (P<0.05).TT₃ and FT₃ were negatively correlated with LAD, LVDd, IVST and LVMI (P<0.05). PTH was positively related to LAD, LVDd, IVST and LVMI (all P<0.01). CRP was positively correlated with LAD, LVDd, IVST and LVMI (P<0.05). Conclusions Selenium deficiency may aggravate left ventricular structural and functional abnormalities in MHD patients by reducing antioxidant capacity, disturbing TH and PTH metabolism and increasing inflammation.