Postprandial Hypertriglyceridemia and its Association with Carotid Intima-Media Thickness in Patients with Type 2 Diabetes Mellitus: An Observational Study

Abstract

Background: Dyslipidemia is a well-recognized metabolic disturbance in type 2 diabetes mellitus (T2DM), and fasting lipid measurement may underestimate atherogenic risk because most of the day is spent in a postprandial state. Postprandial hypertriglyceridemia (PPHTG) may contribute to subclinical atherosclerosis, but its relationship with carotid intima-media thickness (CIMT) is not routinely assessed in clinical practice.

Objective: To evaluate postprandial triglyceride levels and their association with CIMT, measured by high-resolution B-mode ultrasonography, in patients with T2DM.

Methods: In this observational study conducted over 18 months in the Department of General Medicine, 50 adults with T2DM (age 18–65 years) were enrolled after excluding type 1 diabetes, diabetes duration under one year, established cardiovascular or ischemic heart disease, and hypertension or hyperlipidemia. Fasting triglycerides (FTG) and 4-hour postprandial triglycerides (PPTG) were measured, and participants were stratified into three groups: Group A (FTG <150 mg/dL and PPTG <150 mg/dL, n=15), Group B (FTG <150 mg/dL and PPTG ≥150 mg/dL, n=15), and Group C (FTG ≥150 mg/dL and PPTG ≥150 mg/dL, n=20). CIMT was measured by high-resolution B-mode ultrasonography. Group comparisons used chi-square and ANOVA, and associations with CIMT were assessed by Pearson correlation; p<0.05 was considered significant.

Results: Mean CIMT increased progressively across groups (Group A 0.97±0.32 mm, Group B 1.68±0.59 mm, Group C 1.91±0.49 mm; p<0.001). PPTG correlated strongly with CIMT (r=0.621, p<0.001), as did duration of diabetes (r=0.681, p<0.001) and age (r=0.622, p<0.001); FTG showed a weaker but significant correlation (r=0.327, p=0.021). Notably, Group B — with normal fasting but elevated postprandial triglycerides — already showed significantly increased CIMT compared with Group A, indicating that isolated postprandial hypertriglyceridemia is associated with early vascular change. Fasting and postprandial blood glucose, HbA1c, blood pressure, LDL, HDL, and BMI showed no significant association with CIMT (all p>0.05).

Conclusion: Postprandial hypertriglyceridemia, even in the presence of normal fasting triglycerides, is significantly associated with increased CIMT in patients with T2DM and appears to be a more sensitive marker of subclinical atherosclerosis than conventional fasting lipid or glycemic parameters. Postprandial triglyceride assessment, alongside CIMT screening, may merit inclusion in the routine cardiovascular risk evaluation of patients with T2DM.