Small dense low density lipoprotein-cholesterol distribution in people with normolipidemia and hyperlipidemia and the correlation with serum lipids / 中华检验医学杂志

ABSTRACT

Objective To investigate the distribution characteristics of serum small dense low density lipoprotein-cholesterol (sdLDL-C) levels in healthy normolipidemia and hyperlipidemia and analyze the correlation between sdLDL-C and other serum lipids.Methods Totally 1012 normolipidemic subjects (18 93 years old,503 male,509 females) were grouped according to gender and age (18 -29,30 -69 and ≥70 years old).And 433 hyperlipidemic subjects (23 -90 years) were divided into the following 3 groups based on fasting triglyceride (TG) and low density lipoprotein-cholesterol (LDL-C)levelshypertriglyceridemia (n =165 ),high-LDL-C ( n =129) and combined hyperlipidemia ( n =139 ).The sdLDL-C and other serum lipids were measured by Olympus AU2700 automatic analyzer.Analysis of Variance and Kruskal-Wallis H test was used for statistical analysis.Results The distribution of the sdLDL-C levels in normolipidemic subjects was near normal distribution.The sdLDL-C levels had differences in gender and age.In the 18 -29 and 30 -69 years old group,the mean values of sdLDL-C were significantly higher in males than in females [ (0.55 -0.21 ) mmol/L vs (0.47 ±0.22) mmol/L,t =2.212,P =0.028 and (0.66±0.28) mmol/L vs (0.62±0.25) mmol/L,t =2.121,P=0.034].In the ≥70 years old group,the difference of sdLDL-C levels in gender was not statistically significant [ male ( 0.54 ± 0.21 )mmol/L vs female (0.54 ± 0.22 ) mmol/L,t =0.022,P =0.982] ; the mean value was ( 0.54 ± 0.22 ) mmol/L The hyperlipidemic subjects had conspicuous higher levels of sdLDL-C compared with normolipidemia [ ( 1.25 ±0.44) mmol/L vs (0.60 ±0.26) mmol/L,t =29.306,P ＜0.001 ].Among all of groups,the combined hyperlipidemia group had the highest sdLDL-C level [ ( 1.52 ± 0.49) mmol/L,F =525.66,P ＜0.001 ] ; the hypertriglyceridemia group had the highest sdLDL-C/LDL -C level (0.47 ±0.12,F =287.93,P ＜0.001 ) and the high-LDL-C group had the highest level of non-sdLDL-C [LDL-C subtract sdLDL-C,(2.71 ± 0.52) mmol/L.F =336.32,P ＜ 0.001 ].The sdLDL-C showed a good positive correlation with TC,TG,LDL-C,ApoB and BMI ( rs =0.66,0.68,0.65,0.79 and 0.27,P ＜ 0.001 ),and negative correlation with HDL-C and ApoA1 ( rt =- 0.42 and - 0.37,P ＜ 0.001 ).Based on partial correlative analysis,sdLDL-C showed a different correlation with TG,LDL-C and TC ( r =0.42,0.28 and 0.15,P ＜ 0.001 ).Conclusions LDL-C and TG are the important factors influencing the sdLDL-C levels.However,TG has greater effect than LDL-C.The sdLDL-C is an appropriate and good index to evaluate the small dense low density lipoprotein (sdLDL) mass and the overall situation of lipid metabolism.In order to make full use of sdLDL in the clinical treatment and health assessment,it is necessary to establish sdLDL-C reference intervals through the survey of distribution of sdLDL-C levels in different geographic areas.