Glycemic fluctuation and endothelial function in patients of coronary heart disease complicated with type 2 diabetes mellitus

Abstract

Objective To investigate the glycemic fluctuation and endothelial function in patients of coronary heart disease complicated with type 2 diabetes mellitus (T2DM).Methods Fifty eight patients with coronary heart disease were enrolled in the study,including 40 cases complicated with T2DM (group A) and 18 cases without T2DM (group B).All subjects underwent continuous glucose monitoring system (CGMS) and high-resolution ultrasound detection on brachial artery for endothelium-dependent flowmediated dilatation (FMD).According to the results of CGMS,patients with 3 times of standard deviation of blood glucose (SDBG) less than a mean blood glucose in group A were classified as low glucose excursion group (group A1 ),others were classified as high glucose excursion group (group A2 ).The association of glucose fluctuation with FMD in group A was analyzed.Results Compared to group B,the levels of mean amplitude of glycemic excursions (MAGE),the largest amplitude of glycemic excursions (LAGE) and mean postprandial glucose excursion (MPPGE) were elevated and the levels of FMD were lower in group A1 and A2 (P ＜0.05).Compared to group A1 the levels of MAGE,LAGE,MPPGE and absolute means of daily differences were significantly higher [(5.4 ±0.9) vs.(3.7±0.4),(6.3 ± 1.8) vs.(4.6 ±0.8),(4.7±1.0) vs.(3.5±1.2),(2.45 ±0.75) vs.(1.81 ±0.66)mmol/L,respectively]and the FMD levels were lower [ (3.2 ± 1.0) vs.(5.2 ± 1.2) ％ ]in group A2 ( all P ＜ 0.05 ).All CGMS parameters were significantly correlated with FMD in group A2 (P ＜ 0.05 ).Multiple stepwise regression analysis showed that MAGE,systolic blood pressure were the independent impact factors of FMD.Conclusions Patients of coronary heart disease complicated with T2DM have prominent glycemic fluctuation and decreased FMD and the glycemic fluctuation may be associated with the impairment of FMD. Key words: Coronary disease; Diabetes mellitus, type 2; Glucose fluctuation; Vasodilation