Blood Viscosity in Subjects With Type 2 Diabetes Mellitus: Roles of Hyperglycemia and Elevated Plasma Fibrinogen

Jiehui Sun; Keqin Han; Miao Xu; Lujuan Li; Jin Qian; Li Li; Xuejin Li

doi:10.3389/fphys.2022.827428

Blood Viscosity in Subjects With Type 2 Diabetes Mellitus: Roles of Hyperglycemia and Elevated Plasma Fibrinogen

Front Physiol. 2022 Feb 25:13:827428. doi: 10.3389/fphys.2022.827428. eCollection 2022.

Authors

Jiehui Sun¹, Keqin Han², Miao Xu¹, Lujuan Li², Jin Qian², Li Li¹, Xuejin Li²

Affiliations

¹ Department of Endocrinology and Metabolism, Ningbo First Hospital, Ningbo, China.
² Department of Engineering Mechanics, Zhejiang University, Hangzhou, China.

Abstract

The viscosity of blood is an indicator in the understanding and treatment of disease. An elevated blood viscosity has been demonstrated in patients with Type 2 Diabetes Mellitus (T2DM), which might represent a risk factor for cardiovascular complications. However, the roles of glycated hemoglobin (HbA_1c) and plasma fibrinogen levels on the elevated blood viscosity in subjects with T2DM at different chronic glycemic conditions are still not clear. Here, we evaluate the relationship between the blood viscosity and HbA_1c as well as plasma fibrinogen levels in patients with T2DM. The experimental data show that the mean values of the T2DM blood viscosity are higher in groups with higher HbA_1c levels, but the correlation between the T2DM blood viscosity and the HbA_1c level is not obvious. Instead, when we investigate the influence of plasma fibrinogen level on the blood viscosity in T2DM subjects, we find that the T2DM blood viscosity is significantly and positively correlated with the plasma fibrinogen level. Further, to probe the combined effects of multiple factors (including the HbA_1c and plasma fibrinogen levels) on the altered blood viscosity in T2DM, we regroup the experimental data based on the T2DM blood viscosity values at both the low and high shear rates, and our results suggest that the influence of the elevated HbA_1c level on blood viscosity is quite limited, although it is an important indicator of glycemic control in T2DM patients. Instead, the elevated blood hematocrit, the enhanced red blood cell (RBC) aggregation induced by the increased plasma fibrinogen level, and the reduced RBC deformation play key roles in the determination of blood viscosity in T2DM. Together, these experimental results are helpful in identifying the key determinants for the altered T2DM blood viscosity, which can be used in future studies of the hemorheological disturbances of T2DM patients.

Keywords: RBC aggregation; RBC deformation; blood flow; blood viscosity; diabetes mellilus; red blood cell.