The correlation between TG vs remnant lipoproteins in the fasting and postprandial plasma of 23 volunteers

Background: Two recent publications report that non-fasting triglycerides concentrations in plasma are more predictive of cardiovascular events than conventional measurements of fasting triglycerides. While these observations are consistent with the previous studies, direct correlations between remnant lipoprotein triglyceride (RLP-TG) and remnant lipoprotein cholesterol (RLP-C). which are also considered to be risk factors for cardiovascular disease, and fasting and postprandial TG have not been investigated. Methods: On four different days. both fasting and postprandial blood samples were collected from twenty-three overweight to obese men and women at UC Davis and analyzed for plasma concentrations of TG, RLP-C and RLP-TG. Results: Significantly higher correlations between plasma TG and RLPs were observed in the postprandial state (RLP-C r(2) = 0.85; RLP-TG r(2) = 0.92) than in the fasting state (RLP-C r(2) = 0.61; RLP-TG r(2) = 0.73). The differences in the correlations between the fasting and postprandial TG and RLPs were statistically significant (p<0.001). The increase of RLP-TG (postprandial RLP-TG minus fasting RLP-TG) consisted of approximately 80% of the total increase of TG (postprandial TG minus fasting TG). Conclusion: Postprandial TG vs remnant lipoprotein concentrations were significantly more correlated when compared with fasting TG vs RLP concentrations. The increased TG in the postprandial state mainly consisted of TG in remnant lipoproteins. Therefore, the increased sensitivity of non-fasting TG in predicting the risk for cardiovascular events may be directly explained by the increase of remnant lipoproteins in the postprandial state. (C) 2009 Elsevier B.V. All rights reserved.