Variability in cholesterol content and physical properties of lipoproteins containing apolipoprotein B-100

The primary objective of this study was to determine the variability in cholesterol carrying capacity of low density lipoproteins (LDLs) and other apolipoprotein B (apo B)-containing lipoproteins in normolipidemic men. One hundred and fifty-nine normolipidemic men, ages 21 to 73 years, were enrolled. In addition to determining plasma lipids and lipopropoteins, three primary measurements were made: ratios of cholesterol to apo B in LDL; the electrophoretic pattern of LDL, i.e. pattern A, AB, or B; and levels of cholesterol in all lipoproteins other than high density lipoproteins (nonHDL-cholesterol) along with total apo B. First, the data revealed that about 85% of the variability of LDL-cholesterol levels can be accounted for by LDL-apo B levels, whereas the remaining 15% can be explained by differences in LDL-cholesterol/apo B ratios. Second, LDL electrophoretic pattern A was the predominant pattern in young adult men, but in older men the pattern shifted increasingly to AB and B. And third, there was a high correlation between nonHDL-cholesterol levels and total apo B levels, which suggests that nonHDL-cholesterol can be used as a relatively accurate surrogate for total apo B levels in normolipidemic individuals.