Postprandial triglyceride responses and endothelial function in prediabetic first-degree relatives of patients with diabetes.

BACKGROUND: Only a few studies have reported on postprandial lipid responses and endothelial function in prediabetic subjects. None of the study has compared role of familial predisposition in determining postprandial endothelial dysfunction and postprandial hypertriglyceridemia in subjects with prediabetes.

OBJECTIVE: The objective was to study the postprandial triglyceride (PPTG) responses and endothelial function in prediabetic first-degree relatives of patients with diabetes.

METHODS: Thirty-nine subjects were recruited on the basis of oral glucose tolerance test into 3 groups: group 1, prediabetic subjects who had a first-degree relative with diabetes; group 2, prediabetic subjects without family history of diabetes; and group 3, normal glucose tolerance subjects without family history of diabetes. Oral fat challenge test was performed in all study subjects and PPTG responses were measured up to 8 hours. Postprandial endothelial function after 4 hours of fat challenge was estimated by flow-mediated dilation.

RESULTS: Postprandial endothelial dysfunction was greatest in group 1 and significantly higher in group 1 compared with group 2 (P < .001) and group 2 compared with group 3 (P < .001). PPTG responses (TG-AUC, TG-peak, TG-6 hour, and TG-8 hour) were significantly higher in group 1 compared with groups 2 and 3. However, they were similar between groups 2 and 3. Endothelial function showed significant negative correlation with TG-6 hour and TG-8 hour.

CONCLUSION: Prediabetic subjects respond to fat challenge with a greater degree of TG response and endothelial dysfunction compared with normal glucose tolerance subjects especially if they have a first-degree relative with diabetes. This may contribute to enhanced cardiovascular risk reported in prediabetic individuals.