Haemorheologic and fibrinolytic evaluation in obese children and adolescents

Abstract

The haemorheologic condition was evaluated in 43 obese children and 35 controls. In 18 of the obese children and in 21 controls the euglobulin lysis time (ELT) was also studied. Blood viscosity at 94.5 and at 0.204 s-1 shear rates, plasma viscosity, fibrinogen and erythrocyte filtration time were significantly higher in obese than in control children. No significant differences were observed in haematocrit levels. Triglycerides, non-esterified fatty acids (NEFA), pre-beta-lipoprotein and insulin rates were all significantly higher in obese than in control children. There were no significant differences in glycaemia and in haemoglobin A1 values. ELT, both basal and after stimulation with 1-deamino-8-D-arginine-vasopressin (DDAVP), was significantly higher in the obese than in control children. The haemorheologic disturbances together with alterations of the haemostatic balance and fibrinolysis may be an important risk factor for the development of vascular changes at paediatric age.

Increased synthesis rate of fibrinogen as a basis for its elevated plasma levels in obese female adolescents

“…Several studies have established the connection between elevated levels of plasma fibrinogen, obesity, and CVD (4,6,8,14,24,25). However, it remains unclear whether an elevated plasma level of fibrinogen is a consequence of increased fibrinogen synthesis or decreased fibrinogen degradation.…”

Association of hyperviscosity and subclinical atherosclerosis in obese schoolchildren

“…Several haemorheological studies on paediatric subjects have been reported since the late 1980s. They showed elevated plasma viscosity, higher whole blood viscosity at both low and high shear rates and prolonged erythrocyte filtration time in obese Italian children and adolescents [4] and elevated plasma viscosity and erythrocyte aggregation in Spanish children with familiar hypercholesterolaemia [9]. Hypertensive obese children from Hungary had an elevated plasma viscosity, blood viscosity and platelet aggregation [13].…”

Moderate weight reduction improves red cell aggregation and factor VII activity in overweight subjects

“…11 Elevated whole blood and plasma viscosities have been shown in overweight subjects when compared with those within the range of 20±25 kgam 2 BMI, 29 and also in overweight subjects with an elevated WHR compared with those with an acceptable ratio (`0.8 for women,`1.0 for men). 31 Raised plasma and whole blood viscosities have been reported in studies of the overweight. 8,11,12 Poggi et al 11 signi®-cantly reduced plasma viscosity in subjects when achieving a weight loss of 15 kg from a starting BMI exceeding 30 kgam 2 .…”

“…study 11 was 5% higher than in our study, although the values measured in this study were comparable with a representative West of Scotland population. 31 An 11% weight loss in adolescents with BMI greater than 30 kgam 2 reduced plasma viscosity signi®cantly, 8 and in adults a 17% weight loss from a BMI of 42.6 signi®cantly reduced plasma viscosity. 32 Increased WHR in¯uenced blood rheology, particularly whole blood viscosity, and haematocrit, 31 but not plasma viscosity.…”

“…31 An 11% weight loss in adolescents with BMI greater than 30 kgam 2 reduced plasma viscosity signi®cantly, 8 and in adults a 17% weight loss from a BMI of 42.6 signi®cantly reduced plasma viscosity. 32 Increased WHR in¯uenced blood rheology, particularly whole blood viscosity, and haematocrit, 31 but not plasma viscosity. Blood viscosity showed signi®cant reductions with a 17% weight loss when differences were corrected at 45% haematocrit, and measured at a low shear rate.…”