Postchallenge plasma glucose excursions, carotid intima-media thickness, and risk factors for atherosclerosis in Chinese population with type 2 diabetes

Abstract

Aims: Isolated hyperglycemia is associated with atherosclerosis in individuals with type 2 diabetes, but the relationship between postchallenge glucose excursion and atherosclerosis is less clear. This study examines the relationships between postchallenge glucose spikes (PGS), carotid intima-media thickness (IMT), and traditional risk factors for atherosclerosis in individuals with type 2 diabetes.

Methods: A total of 474 individuals with type 2 diabetes who were within the highest or lowest IMT distribution quartile were included. The Student's t-test, one-way analysis of variance (ANOVA), single variate and multivariate analyses were implemented to study the data. An additional healthy control group (n=896) was selected during routine health examination. They were Han nationality and unrelated to the diabetic patients.

Results: (1) Compared with subjects of healthy control group, the subjects with type 2 diabetes had significantly higher levels of body mass index (BMI), waist-to-hip ratio (WHR), systolic blood pressure, triglyceride, total cholesterol, low density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG), 120 min postchallenge glucose (PG120), hemoglobin A1c (HbA1c) and IMT (P < or = 0.01) and relatively lower levels of high density lipoprotein cholesterol (HDL-C) (P < or = 0.05). (2) According to the IMT which was measured by B-mode ultrasonography, the patients of type 2 diabetes could be divided into two subgroups: one was the subgroup of IMT > or = P(75) and another was the subgroup of IMT < or = P(25). Compared with subjects of IMT > or = P(25) subgroup, subjects being in the IMT > or = P(75) subgroup exhibited significantly increased age, WHR, diabetes duration, systolic blood pressure, total cholesterol, triglyceride, LDL-C, and significantly decreased HDL-C levels. And among all the plasma glucose variables, except for FPG and PG30, all the other variables (include PG60, PG120, PG180, PGS, HbA1C, under area curve of glucose) showed a significant increase in the IMT>/=P(75) subgroup. (3) A multivariate logistic regression analysis was performed to establish which were independently related with carotid IMT, and the results showed the PGS was identified as the strongest determinant of IMT from all the atherosclerosis risk factors. (4) PGS is significantly correlated to a variety of atherosclerosis risk factors.

Conclusions: This study identified several important associations between PGS and known risk factors for atherosclerosis and suggested that PGS is independently related to carotid IMT. Wide postchallenge glucose excursions may contribute to the development of atherosclerosis in individuals with type 2 diabetes, independent of other risk factors.