Lipid composition and interrelationships of major serum lipoproteins. Observations in children with different lipoprotein profiles. Bogalusa Heart Study.

Abstract

Cholesterol (C) and triglyceride (T) contents and their relationship within serum lipoproteins, very low density lipoproteins (VLDL), low density lipoproteins (LDL) and high density lipoproteins (HDL) were determined in subgroups of children (n =360) from a total biracial community whose earlier .beta.- and/or pre-.beta.-lipoprotein cholesterol levels were in the extreme percentiles of the distribution. The lipid content of lipoproteins was analyzed following fractionation by ultracentrifugation. In addition to previously known race- and sex-related differences for lipoprotein cholesterol levels, results indicated that white children had significantly higher VLDL-T and LDL-T and lower VLDL-C/T and LDL-C/T ratios than black children. Although HDL-T levels were the same in both races, girls had significantly higher levels than boys. Children with low pre-.beta.-lipoprotein cholesterol levels earlier had consistently higher VLDL-C/T, LDL-C/T and HDL-C/T ratios than children with high pre-.beta.-lipoprotein cholesterol. Children with high .beta.- and low pre-.beta.-lipoprotein cholesterol and low pre-.beta.-lipoprotein cholesterol earlier showed the highest LDL-C/T ratio, suggesting that LDL particles in this group may have less fluid lipid core. Despite a very high correlation between VLDL-C and VLDL-T, definite compositional differences were noted in certain children with elevated pre-.beta.-lipoprotein cholesterol levels. The relationship of LDL-C and LDL-T was significant but not high; there was complete lack of relationship between HDL-C and HDL-T. HDL-C in terms of percent of serum total cholesterol was highest in children with low .beta.- and pre-.beta.-lipoprotein cholesterol, while corresponding values were lowest in children with high .beta.- and pre-.beta.-lipoprotein cholesterol. While no significant associations between age and lipoprotein lipids were noted in children who had low .beta.- and pre-.beta.-lipoprotein cholesterol, such trends were observed mainly in boys with elevated .beta.- and/or pre-.beta.-lipoprotein cholesterol; a significant negative association between HDL-C and age was noted only in white boys stratified in this manner. These data provide baseline values for children with different lipoprotein profiles and may help identify at an early stage children with lipoprotein patterns and characteristics that are potentially atherogenic.