The Correlations Among Glycosylated Hemoglobin,Peripheral Vascular Ultrasonic Parameters And Blood Viscosity In Patients With Type 2 Diabetes Mellitus

Objective: To investigate the relationship between glycosylated hemoglobin(Hb A1c)and peripheral vascular ultrasound parameters(arterial diameter,peak systolic velocity,resistance index,presence or absence of plaque),blood lipids and blood viscosity in patients with type 2 diabetes mellitus(T2DM).Methods: Total of 345 patients with type 2 diabetes were examined for fasting serum blood glucose,glycosylated hemoglobin,blood lipids,blood viscosity and other indicators after admission.Ultrasound specialists used ultrasound diagnostic instruments to detect peripheral blood vessels,and to detect peak diameters and systolic peak flow rates,Resistance index,presence or absence of plaque,soft or hard plaque,and plaque size.All patients were divided into four groups according to the Hb A1 c level: group A(Hb A1 c <7.0%,79 cases),group B(7.0% ≤ Hb A1 c <8.5%,94 cases),group C(8.5% ≤ Hb A1 c <10%,95 cases),D Group(Hb A1c≥10.0%,77 cases).SPSS software was used to analyze the correlation between Hb A1 c level and blood lipids and blood viscosity,and the correlation between Hb A1 c and peripheral vascular ultrasound parameters(arterial diameter,peak systolic velocity,resistance index,presence or absence of plaque,etc.)Results: 1.There were significant differences in the whole blood viscosity under 1/s,5/s,30/s and 200/s shear rate and the high shear reductive viscosity of whole blood in each group(P<0.05).The whole blood viscosity of group B,C and D(Hb A1c≥7%)was significantly higher than that of group A(Hb A1c<7.0%)under 1/s,5/s,30/s,200/s shear rate.The high shear reductive viscosity of whole blood in group C and group D(Hb A1c≥8.5%)was significantly higher than that in group A and group B(Hb A1c<8.5%).Spearman correlation analysis showed that Hb A1 c levels were positively correlated with whole blood viscosity under 5/s,30/s and 200/s shear rates and high shear reductive viscosity of whole blood.Multivariate stepwise regression analysis suggested that Hb A1 c had independent correlation with whole blood viscosity at 5/s,30/s and 200/s shear rate and HSRV after adjusting for lipids and other factors(all P<0.05).2.There was no significant difference among four groups of patients in the diameter,PSV and RI of bilateral carotid artery(common carotid artery,internal carotid artery),and in the diameter of femoral artery(common femoral artery,superficial femoral artery opening,middle segment of superficial femoral artery)and dorsal femoral artery(P>0.05).There was no significant difference in the detection rate of carotid plaque,the rate of detection of femoral plaque,the rate of bilateral carotid plaque detection,and the rate of bilateral plaque in femoral artery(P>0.05).There was no significant correlation between Hb A1 c and peripheral vascular ultrasound parameters(P>0.05).But multivariate stepwise regression showed a significant negative correlation between Hb A1 c level and left and right internal carotid artery diameter after correcting all relevant factors(P<0.05).3.The differences of TC,TG,HDL-C and LDL-C between the groups were statistically significant(P=0.000).Multiple comparison analysis between groups showed that the TG level in the glycemic control ideal group(group A)was significantly lower than that in glycemic control undesirable group(groups B,C,and D)and HDL-C levels were significantly higher than in glycemic control undesirable group(groups B,C,and D).The levels of TC and LDL-C were significantly lower than those with extremely poor glycemic control(group D).Spearman correlation analysis showed that Hb A1 c levels were positively correlated with TC,TG and LDL-C(TC: r=0.267,p=0.000;TG: r=0.293,p=0.000;LDL-C: r=0.253,p= 0.000),Hb A1 c level was negatively correlated with HDL-C(r=-0.213,p=0.000).Conclusion: The blood Hb A1 c level in T2 DM patients is positively correlated with blood viscosity,HSRV and the lipid metabolism disorder,suggesting that Hb A1 c maybe has a significant effect on microcirculation.In addition,the blood Hb A1 c level in T2 DM patients is negatively correlated with left and right internal carotid artery diameter.But this study did not find a significant correlation between blood Hb A1 c and peripheral arterial blood flow velocity.