Obesity-related increase in whole blood viscosity includes different profiles according to fat localization

Abstract

In a precedent study we observed that overall adiposity evaluated with the body mass index (BMI) was correlated with plasma viscosity and red blood cells (RBC) aggregation while abdominal obesity as assessed with the waist to hip ratio (WHR) was correlated with hematocrit. We investigated this issue in 129 women (age 15-65 years, BMI: 15 to 44 kg/m 2 , WHR: 0.65 to 1.13, fatness: 12-58%) who were divided into fatness groups: 17 underweight women (BMI <18.5), 75 normal weigh (BMI 18.5-24.9), 11 overweight (BMI 25-29.9), and 26 obese (BMI >30) divided according to WHR into 13 lower body and 13 upper body obese women. Whole blood viscosity significantly increases across obesity classes, and is higher in upper body than in lower body obesity (2.84 ± 0.08 vs 3.29 ± 0.09 mPa.s, p < 0.05). The correlations between whole blood viscosity and BMI (r = 0.383 p < 0.01) and WHR (r = 0.364 p < 0.01) are found again. The former is explained by correlations of BMI with plasma viscosity (r = 0.303 p < 0.01) and red cell rigidity (r = 0.356 p < 0.01) and the latter is only explained by a correlation between WHR and hematocrit (r = 0.524 p < 0.01). BMI is also correlated with RBC aggregation parameters. Actually, when total fatness is evaluated with the percentage of fat (%fat) given by bioimpedance analysis (BIA), the picture is slightly different, since %fat is correlated with whole blood viscosity and RBC aggregation parameters but not with hematocrit, plasma viscosity and red cell rigidity. Fat free mass is also correlated with whole blood viscosity (r = 0.227 p < 0.02) due to a correlation with hematocrit (r = 0.483 p < 0.01) but neither RBC rheology nor plasma viscosity. This study shows that fatness by its own is associated with increased red cell aggregation, that abdominal fat increases blood viscosity due to a rise in hematocrit, and that overall body size as assessed with the BMI is associated with increased plasma viscosity and red cell rigidity.

Pilot clinical study of quantitative ultrasound spectroscopy measurements of erythrocyte aggregation within superficial veins

“…This difference in RBC aggregation according to sex was already reported using ex vivo laser backscatter measurements [34]. On the other hand, a relation between obesity and erythrocyte aggregation has also been described [35][36][37]. The current cohort was composed of healthy participants having a BMI around 25 and did not include obese individuals.…”

“…Participants were lying down on an exam bed and ultrasound data were acquired on the palmer side of the forearm on the antebrachial vein, and on the tibial vein on the front of the leg. Ultrasound acquisitions were performed with a high-frequency scanner (Vevo770, 35 MHz central frequency probe #RMV-703, Visualsonics, Toronto, Canada). For each measurement site, veins with a diameter larger than 1 mm were quested to facilitate ultrasound post-processing.…”

Influence of benzene exposure, fat content, and their interactions on erythroid-related hematologic parameters in petrochemical workers: a cross-sectional study

“…The reason for using BF% instead of BMI to represent the body fat content was that BF% is a better predictor for body fat mass based on age and gender [19,31]. Studies have shown that some erythroid-related hematologic parameters, such as RBC count, Hb, and HCT, were significantly positively correlated with waist to hip ratio and waist circumference [32,33]. In the present study, we also observed that BF%, TC, and TG are significantly positively associated with erythroid-related hematologic parameters in linear or r-shaped dose-response patterns, and workers with fatty liver disease had higher RBC count, Hg concentration, and HCT% than their non-diseased counterparts.…”

“…The underlying mechanisms of the effects of fat content on erythroid-related hematologic parameters may hinge upon membranes of erythrocytes, which are rich in polyunsaturated fatty acids, being very sensitive to changes in fat content in vivo [34]. Excessive fat content may cause abnormal counts and function of RBCs by affecting their membrane composition, fluidity, and rheology [32].…”

Integrative analysis of blood and gut microbiota data suggests a non-alcoholic fatty liver disease (NAFLD)-related disorder in French SLAdd minipigs

“…hematocrit and hemoglobin, were significantly higher in DD pigs over almost the whole time-course, making the finding more robust. High levels of hematocrit and hemoglobin are associated with obesity and metabolic syndrome 36,37 , respectively, and both metrics are related to insulin resistance, NAFLD and NASH in humans [38][39][40] . Mean corpuscular volume was also higher in DD pigs; however, even though this parameter is increased in some liver pathologies, it does not seem to be linked to NAFLD 41 .…”