The Risk Factors Of25-hydroxivitamin D₃in Non-dialyzed Patients With Chronic Kidney Disease And The Effects Of25-hydroxivitamin D₃on Lipid

Objective:To study the related factors of25-hydroxivitamin D₃[25（OH）D₃] in non-dialyzedpatients with chronic kidney disease （CKD） and to investigate the effects of25（OH）D₃onlipids.Methods:The present study included156non-dialyzed patients with CKD in the nephrologydepartment of the second affiliated hospital of Soochow University from January2011toDecember2012. On enrollment, the patients’ gender, age, month of the year and morbiditywith diabetes were recorded. Serum concentrations of25（OH）D₃,biochemical dataincluding serum total cholesterol, low density lipoprotein, high density lipoprotein,triglycerides, albumin, serum creatinin, blood urea nitrogen and24-h urine protein wereexamined. Differences with P values＜0.05were considered as significant. Statisticalanalyses were performed using the SPSS software version17.0.Results:1. The average level of25（OH） D₃was（43.71±19.93）nmol/L. Deficiency （＜37.5nmol/L） of25（OH）D₃was observed in41.67%（65/156）, insufficiency （≥37.5nmol/L and＜75nmol/L） in52.56%（82/156）and normal（≥75nmol/L） in5.77%（9/156） of thepatients. Patients with albumin＜35g/L， proteinuria≥1.5g/d, eGFR （estimatedglomerular filtration rate）＜45ml/min had lower level of25（OH）D₃（P＜0.05）. Nodifferences in levels of25（OH）D₃were found regarding morbidity with diabetes, the levelof total cholesterol, gender, age, whether supplying vitamin D, season of the year（P≥0.05）.Serum25（OH）D₃level correlated with eGFR（r=0.188，P=0.019） and albumin（r=0.281，P=0.001），correlated inversely with24-h urine protein（r=-0.322，P=0.001）, total cholesterol（r=-0.203，P=0.011）.No association of25（OH）D₃with age（r=0.044，P=0.587）. Multivariable regression analysis showed that24-h urine protein and eGFRwere independent risk factors of25（OH）D₃.2．A quarter （39/156） of the patients’ lipid was normal and three quarter （117/156） ofthat was abnormal. Serum25（OH）D₃level correlated inversely with total cholesterol（r=-0.203，P=0.011）, low density lipoprotein（r=-0.205，P=0.010）, triglycerides（r=-0.187，P=0.019）, No association of25（OH）D₃with high density lipoprotein（r=-0.040，P=0.612）. Levels of total cholesterol, low density lipoprotein cholesterol werelower among patients with25（OH） D₃≥37.5nmol/L when compared with25（OH） D₃＜37.5nmol/L（P＜0.05）.No differences in levels of high density lipoprotein cholesterol andtriglycerides were found（P≥0.05）.Conclusions:1. Hypovitaminosis D is a condition highly prevalent among patients suffering fromCKD. Blood albumin,24-h urine protein and eGFR influenced25（OH） D₃level. Grossproteinuria and impaired renal function were the risk factors of hypovitaminosis D innon-dialyzed CKD patients.2. The incidence rate of dyslipidemia in non-dialyzed patients with CKD was high. Highserum25（OH）D₃concentration was associated with a lower serum lipid level.