Background:Current reports claim that small and dense LDL particles are more atherogenic than larger LDL particles. There are many studies presenting LDL subclass distribution in adults, but there is not enough data regarding children in the literature on this problem. The aim of our study was to examine LDL subclass distribution in healthy children in the Republic of Macedonia.Material/Methods:Plasma LDL subclasses in 100 children aged 9–18 years were analyzed using non-denaturing polyacrilamide gradient (3–31%) gel electrophoresis. Conventional plasma lipid and apoprotein parameters thought to be related to LDL size were determined as well.Results: The results obtained showed the prevalence of large LDL subclasses (phenotype A) in 89% of the children, whereas small LDL subclasses (phenotype B) were observed in 11%. The mean LDL size was 26.37±0.68 nm, and there was no difference between gender groups. No association was noted between LDL size and plasma lipid and apoprotein levels, age, or BMI.Conclusions:LDL size and distribution is not gender- or age-dependent, or influenced by plasma lipid and apoprotein concentrations in childhood. This suggests that analysis of LDL subclass phenotype may provide better information on the risk of atherosclerosis development in adulthood.

Keywords: Apoproteins - blood, Lipoproteins, LDL - classification, Macedonia (Republic) - epidemiology, Adolescent, Apoproteins - blood, Arteriosclerosis - epidemiology, Body Mass Index, Child, Lipoproteins, LDL - classification, Macedonia (Republic) - epidemiology, Risk, Sex Factors