LIPID STATUS ASSOCIATION WITH 25-HYDROXY VITAMIN D: CROSS SECTIONAL STUDY OF END STAGE RENAL DISEASE PATIENTS

Abstract

Background:Some observational studies indicate an association of 25-hydroxy vitamin D (25(OH)D) insufficiency and atherogenic cholesterol concentrations. The aim of this study was to investigate relationship between 25(OH)D concentrations and lipid parameters in end stage renal disease (ESRD) patients, separately for predialysis, hemodialysis and peritoneal dialysis patients.Methods:We have adjusted 25(OH)D concentrations for seasonal variability with cosinor analysis, and performed all further analysis using these corrected 25(OH)D concentrations. Concentrations of 25(OH)D and the lipid parameters were determined in 214 ESRD patients and 50 control group participants. The analysis included the measurement of 25(OH)D by HPLC, apolipoprotein (Apo) AI, ApoB andLp(a) by nephelometry, total cholesterol (TC), high-densitylipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) by spectrophotometry and manually calculated ApoB/ApoAI and LDL-C/HDL-C ratio.Results:ESRD patients with adjusted 25(OH)D concentrations of ≤ 50 nmol/L had significantly higher TC (P =0.005) and ApoAI (P = 0.049). Significantly higher HDL-C (P = 0.011) and ApoAI (P = 0.020) were found in hemodialysis patients with the 25(OH)D concentrations of ≤ 50 nmol/L. The other analyzed lipid parameters differed significantly between predialysis, hemodialysis and peritoneal dialysis patients with 25(OH)D concentrations of <50 nmol/L. Conclusions:Our study indicate the significant relationship between 25(OH)D repletion and optimal concentrations of lipid parameters in ESRD patients. Further research is necessary to explain whether joint evaluation of vitamin D status and lipid abnormalities could improve cardiovascular outcome in ESRD patients.

Uvod: Opservacione studije ukazuju na povezanost nedostatka 25-hidroksi vitamin D (25(OH)D) i koncentracija aterogenog holesterola. Cilj ove studije bio je da se ispita međusobna povezanost 25(OH)D i lipidnih parametara kod bolesnika sa krajnjim stadijumom bolesti bubrega (ESRD) posebno kod predijaliznih, bolesnika na hemodijalizi i peritonalnoj dijalizi. Metode: Podesili smo koncentracije 25(OH)D za sezonsku varijaciju koristeći kosinor analizu, i u daljem ispitivanju smo koristili korigovane koncentracije 25(OH)D. Koncentracije 25(OH)D i lipidnih parametara su određene za 214 ESRD bolesnika i 50 učesnika kontrolne grupe. Analizirali smo koncentracije 25(OH)D metodom HPLC, apolipoproteina (Apo) AI, ApoB i Lp(a) nefelometrijski, ukupnog holesterola (TC), lipoproteina velike gustine (HDL-C), lipoproteina male gustine (LDL-C) i triglicerida (TG) spektro fotometrijski i ručno preračunavali indekse ApoB/ApoAI i LDL-C/HDLC. Rezultati: ESRD bolesnici sa korigovanim 25(OH)D 50 nmol/L su imali značajno viši TC (P = 0,005) i ApoAI (P = 0,049). Značajno više koncentracije HDL-C (P = 0,011) i ApoAI (P = 0,020) smo dobili kod hemodijaliznih bolesnika sa 25(OH)D koncentracijama 50 nmol/L. Ostali analizirani lipidni parametri su bili značajno različiti između analiziranih grupa bolesnika sa 25(OH)D koncentracijama < 50 nmol/L. Zaključak: Naša studija ukazuje na značajnu povezanost dovoljnih nivoa 25(OH)D i optimalnih koncentracija lipidnih parametara kod ESRD bolesnika. Potrebna su dalja istraživanja da bi se objasnilo da li zajednička procena statusa vitamina D i lipidnih abnormalnosti mogu da poboljšaju kardiovaskularni ishod kod ESRD bolesnika.