Deep vein hemodynamics of the lower limbs in obesity

Abstract

Objective To evaluate lower extremity deep venous hemodynamic changes and lower extremity deep venous disease in abdominal obesity.Methods To compare venous flow parameters of the lower limbs as assessed by Duplex ultrasound scanning in obese and nonobese individuals according to body mass index(BMI).Venous hemodynamics were studied in a prospective cohort study in nonobese( BMI ＜ 25 kg/m2) and obese individuals( BMI ＞ 30 kg/m2 ).Diameter,peak,mean,and minimum velocities were assessed.Results The study examined 45 limbs in 24 nonobese individuals and 44 limbs in 22 obese individuals.The diameter of the femoral vein was significantly greater in obese vs nonobese limbs ( 10.4 ± 1.3) mm vs (7.1 ± 1.0) mm,P ＜ 0.01 ).Calculation of venous amplitude and shear stress showed significantly higher values in nonobese vs obese limbs [ ( 11 ± 5 ) vs ( 8 ± 3 ) cm/s ],( P ＜ 0.01 ) and [ (0.50 ± 0.17 ) vs ( 0.30 ± 0.09 ) ] dyn/cm2,( P ＜ 0.01 ).Spearman rank correlation revealed a significant inverse correlation between waist-to-hip ratios and waist circumference and velocities amplitude (peak ve locity-minim velocity),and shear stress.Conclusions Lower limb venous flow parameters differ significantly between obese and nonobese individuals.These findings suggest the mechanical role of abdominal adipose tissue potentially leading to elevated risk for both chronic venous insufficiency and venous thromboembolism. Key words: Obesity; Hemodynamics; Ultrasonography,Doppler,color; Venous insufficiency