Fat mass is responsible for increased plasma and whole blood viscosity in obesity

Our study is centered around a pivotal question: How does the increase in adipose tissue, which defines obesity, impact hemorheological parameters? By delving into this question, we aim to underscore the crucial role of fat tissue increase in obesity, a topic of significant interest and importance in the field of physiology and obesity research.

Individuals with a body mass index (BMI) of 25 and above were included in this study. Height was measured with bare feet on flat surface, then, using the bioimpedance device (Tanita-BC418), weight, BMI, fat percentage, fat mass (FM), and fat-free mass were determined. Using the Brookfield viscometer, several shear rates were utilized (for whole blood, 75, 150, 300, and 450 sec^-1; for plasma 450 sec^-1) in accordance with established standards and test procedures. Whole blood and plasma viscosity were studied in Hamidiye Medical Faculty Hemorheology laboratory.

Plasma viscosity in the obese group was significantly (P = 0.01) higher than in the non-obese group, and increased statistically in proportion to weight, BMI, FM, fat-free mass (P < 0.05) in the obese group. At shear rates of 300 and 450 sec^-1 (P < 0.05) were determined statistically significant differences between the obese and nonobese groups in whole blood viscosity (WBV). In the obese group, WBV at a shear rate of 75, 150, 300, and 450 sec^-1 showed a positive correlation with weight, BMI, FM (P < 0.05).

Increased adipose tissue significantly affect plasma and blood viscosities in obesity. The increase in plasma and WBV is directly associated with the increase in adipose tissue.