Postprandial Lipemia In T2DM And Its Relationship With Carotid Intima-media Thickness

Type 2 diabetes mellitus is frequently associated with premature atherosclerosis. More and more researches have considered that abnormalities in lipopro-tein metabolism are believed to contribute to the increased risk of premature cardiovascular disease in T2DM. People are predominantly in a postprandial state thoughout the day. Most studies of lipoprotein metabolism in T2DM, however, have focused on the fasting state. Recently, some studies demonstrated that measurement of the intima - medial thickness of the common carotid artery ( CCA) by ultrasonography is a noninvasive and quantitative method of evaluating early atherosclerotic changes. To investigate die role of postprandial hyper-triglyceridemia in early atherosclerosis, we studied the postprandial lipid changes in T2DM and the correlation between postprandial TC and carotid IMT values.Materials and methodsSubjects :49 T2DM patients(28 women and 21 men) were recruited, 56.5 11.9 years of age. 43 control subjects(21 women and 22 men) were chosen without any familial or personal history of diabetes, CHD and CVD. 54.2 11. 7 years of age. Hypertention in diabetic and control groups is 15 and 13.Methods:All subjects were measured the height, weight, then calculated BMI. Blood sample were obtained after a 12h overnight fast, the subjects ate a fat - load meal in 15 minutes ( fat :40g/m2). Blood sample were taken again at 2h ,4h after the meal. Plasma glucose, TG, TC, HDL - C and LDL - C were measured by standard laboratory techniques.Measurement of carotid IMT was performed with LOGIQ500 color Doplar apparatus( American GE Corporation) , using a linear array transducer(8. 2 -11MHz). We measured the IMT 3 times of the CCA far wall bilaterally 10mm proximal to the bulb. Hie mean of these values represented the CAIMT of each subject.Statistics: data evaluation was conducted using the SPSS program, t test,x2 test, Pearson correlation coefficient and stepwise regression were used to evaluate the values.ResultsThe diabetic and control groups were thoroughly matched for age, sex, BMI and the incidence of hypertension. (P >0.05)Hie fast and postprandial plasma glucose concentrations were higher in diabetic subjects than in controls. Postprandial BG, TC concentrations were significantly higher and HDL - C lower than fast state in both groups. But DM group has an evident responds in post ?prandial state. There were no significant differences between the two groups for TC and LDL - C concentration in fast and postprandial states.In DM group, postprandial TC positively correlated with fasting TG(r =0. 851,P<0.01), festing insulin(r=0.645,P<0.01), BMl(r=0.638,P <0. 01) and negatively with fasting HDL - C concentration ( r = - 0. 364, P < 0. 05).The diabetic subjects displayed an increased IMT of the CCA compared with controls(0.86mm versus 0.69mm). In DM group, with multivariate step-wise regression, the independent determinants of CAIMT are postprandial 4h TC, fast insulin and age. The linear regression equation is; Y = 0. 274 + 0. 04TG4 +0.009F1NS +0.006age. R2 =0.742Conclusion1. T2DM patients have an exaggerated postprandial lipemia, especially postprandial hypergtyceridemia.2. The postprandial hyperglyceridemia in T2DM is positively related with o-besity, hyperinsulinemia and negatively related with HDL - C.3. In T2DM, We found the postprandial hyperglyceridemia , hyperinsuline-mia and age have a independent correlation with atherosclerosis . This study suggested that it is important to specifically correct lipoprotein abnonnalities in T2DM to reduce the risk of macrovascular complications.