Low density lipoprotein subclass distribution in children with diabetes mellitus

The role of small dense low-density lipoprotein (sLDL) subclasses in atherosclerosis has been demonstrated in many studies. Among other metabolic changes, the alteration in LDL lipoprotein subclass distribution and size has been proved in diabetic adults. Because there is not enough literature data presenting LDL subclass distribution in childhood, the aim of this study was to examine LDL subclass profile in diabetic children compared with healthy control.

Plasma LDL subclasses in 30 children with type I diabetes mellitus and 100 healthy children aged 9-18 years were analyzed using non-denaturing polyacrilamide gradient (3-31%) gel electrophoresis. Conventional plasma lipid and apoprotein parameters which are thought to affect LDL size were determined as well.

Analysis of LDL phenotype has shown that a great percentage of healthy children (89%) yield bigger LDL1 with LDL2 subclasses being dominant (phenotype A), whereas 11 % of the children belong to phenotype B characterized by the presence of small, atherogenic LDL3 and LDL4 subclasses. In diabetic children despite no significant differences in their plasma lipid profile when compared with healthy control, the frequency of LDL phenotype B was increased (86.7 %), and the mean LDL diameter was smaller (p < 0.0001). LDL size was inversely correlated with plasma levels of triglycerides, and positively correlated with plasma HDL cholesterol and BMI.

Although plasma levels for lipid and apoprotein were within the normal range, the increased frequency of LDL phenotype B confirms a grater risk of atherosclerosis development in children with diabetes mellitus. LDL size measurement may potentially help to assess cardiovascular risk and adapt the treatment goals thereafter (Tab. 3, Ref. 38). Full Text (Free, PDF) www.bmj.sk.