Background: Abnormalities in blood rheology may be factors contributing to cardiovascular complications and the progression of renal failure in kidney allograft recipients. The haemorheological variables haematocrit, fibrinogen, whole blood viscosity, plasma viscosity, erythrocyte aggregation tendency and fluidity were measured in 27 cyclosporin A (CyA)-treated patients who had received a renal graft at least 6 months previously. Their creatinine clearance was in the range of 12-92 ml/min/1.73 m2 (mean 55+/-19). The values were compared with those obtained from a control group comprising 20 healthy subjects matched according to age, sex and smoking habits.
Results: The haematocrit, plasma fibrinogen, whole blood viscosity, plasma viscosity, erythrocyte aggregation tendency, body mass index (BMI), mean arterial pressure (MAP) and serum triglycerides were increased in the transplanted patients, and the serum high density lipoprotein (HDL)-cholesterol and erythrocyte fluidity decreased. The haemorheological variables were used as dependent variables in a stepwise regression analysis with age, MAP, BMI, urinary albumin excretion rate, blood CyA concentration, creatinine clearance, and serum triglycerides, cholesterol and HDL-cholesterol as independent variables. Plasma fibrinogen was positively correlated with BMI and blood CyA. The whole blood viscosity was positively correlated with blood CyA and negatively with serum HDL-cholesterol. Only serum triglycerides remained correlated with erythrocyte aggregation tendency.
Conclusions: All variables with a known impact on blood viscosity were altered in the present group of renal transplant recipients. Inappropriate regulation of erythrocyte formation, overweight, the use of CyA, high triglycerides and low HDL-cholesterol levels may be factors contributing to this. The importance of impaired flow properties of blood for the development of cardiovascular diseases and transplant glomerulosclerosis needs to be examined.