Hyperlipidemia in the Pacific Northwest Bell Telephone Company Health Survey. Part 2. Lipoprotein lipid interrelationships.

The relationships of lipoprotein cholesterol and triglyceride among lipoprotein fractions have potential significance for understanding atherogenesis and distinguishing among different classes of hyperlipidemia. We have compared these relationships in normolipidemic, hypercholesterolemic, hypertriglyceridemic, and combined hyperlipidemic participants in the Pacific Northwest Bell Telephone Company Health Survey. The cholesterol/triglyceride ratio in each lipoprotein fraction was moderately higher (1% to 26%) in hypercholesterolemia but significantly lower (20% to 50%) in hypertriglyceridemia, compared to normolipidemia. In combined hyperlipidemia, the very low density lipoprotein ratios were lower than in normolipidemia, but larger than in hypertriglyceridemia. These changes were directionally the same, but differed quantitatively, in both men and women. Correlation coefficients between cholesterol and triglyceride within each fraction varied by gender and sex hormone use. The largest correlations were seen in combined hyperlipidemic men for very low density lipoproteins, normolipidemic men for low density lipoproteins, and combined hyperlipidemic women taking hormones for high density lipoproteins. The correlation of very low and low density lipoprotein cholesterol was generally negative and was strongest for hormone users (r = -0.81) and weakest for nonusers (r = -0.06). Very low density lipoprotein triglyceride and high density lipoprotein cholesterol correlations were generally negative and were strongest in hypertriglyceridemic women not taking hormones (r = -0.55) and weakest in normolipidemic hormone users (r = -0.10). This correlation was positive for hypertriglyceridemic and combined hyperlipidemic hormone users.