Postprandial hypertriglyceridemia and carotid intima–media thickness in north Indian type 2 diabetic subjects

Abstract

Hypertriglyceridemia is an important risk factor for coronary heart disease (CHD) and in the development of atherosclerosis, especially in subgroups of the population like those with type 2 diabetes. Although triglycerides are generally increased in the postprandial period, the association between postprandial triglyceride (ppTG) levels and atherosclerosis has not been investigated in north Indian type 2 diabetic subjects known to have a very high prevalence rate of premature CHD and insulin resistance. To investigate the role of ppTG levels in atherosclerosis in type 2 diabetes, we examined the correlation between ppTG levels and carotid intima–media thickness (IMT). Carotid IMT was determined by high resolution B-mode ultrasonography in 86 newly detected type 2 diabetic subjects (1–12 months duration) having good glycemic control (HbA 1C < 7%) and 45 non-diabetic subjects matched according to age and body mass index (BMI). Plasma glucose, insulin, total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides were measured after overnight fasting. Plasma insulin and glucose were also measured 2 h and plasma triglycerides 4 h after breakfast. The mean carotid IMT in diabetic subjects was higher than those in non-diabetic subjects (0.77 ± 0.15 mm versus 0.53 ± 0.16 mm, P < 0.001). Based on the fasting and postprandial triglyceride levels, the diabetic subjects were divided into three groups: normo–normo (NN); normo–hyper (NH); hyper–hyper (HH) [NN: fTG < 1.70 mmol/L and ppTG < 2.30 mmol/L; NH: fTG < 1.70 mmol/L and ppTG > 2.30 mmol/L; HH: fTG > 1.70 mmol/L and ppTG > 2.30 mmol/L]. Carotid IMT was significantly increased in the NH (0.79 ± 0.09 mm) and HH (0.82 ± 0.06 mm) groups compared with the NN group (0.59 ± 0.09 mm, P < 0.001). Although ppTG, age, fasting LDL-cholesterol, HOMA-estimated insulin resistance, HbA 1C were all independently correlated with carotid IMT, age and ppTG levels had the strongest statistical influence ( P < 0.002).