Affiliations: Augenklinik der RWTH Aachen, Pauwelsstr. 30, D-5100 Aachen | Abteilung für Klinische Hämostaseologie und Transfusionsmedizin, Universität des Saarlandes, D-6650 Homburg
Abstract: Rheological parameters (hematocrit, plasma viscosity and red blood cell aggregation index), glycosylated hemoglobin (HbA1c) and retinal arteriovenous passagetime (AVP) were measured in 93 patients with type I diabetes. The stage of diabetic retinopathy was graded by means of ophthalmoscopy and video fluorescein angiography. The mean values of hematocrit (men 46 ± 4%, women 43 ± 3 %), RBC aggregation index (13,8 ± 3,8, normals: 14,6 ± 3,2) were equal to normals. Plasma viscosity (1,33 ± 0,09 mPas, normals:1,24 ± 0,05 mPas) was increased. The groups with increasing stage of diabetic retinopathy showed no difference in hematocrit, RBC aggregation and HbA1c and an increase of plasma viscosity. In patients with bad glycemic control plasma viscosity was increased and RBC aggregation index was similar as compared with patients with good glycemic control. If retinal arteriovenous passagetime was worse plasma viscosity and RBC aggregation were more increased. This indicates, that alterated plasma viscosity and RBC aggregation may be one of the reasons for disturbed microcirculation and fundus changes ill diabetic retinopathy.
Keywords: Blood rheology, hematocrit, plasma viscosity, red blood cell aggregation, diabetic retinopathy, glycemic control
