Plasma haemostatic factors and diabetic retinopathy

Publisher Website
Google Scholar
Abstract
Plasma coagulation factors were measured in 12 male insulin-dependent diabetics with no retinopathy, 10 with background and 10 with proliferative retinopathy and 10 non-diabetics. Factor VIII pro-coagulant activities (VIII:C), ristocetin cofactor activities and factor VIII-related antigen concentrations (VIIIR:ag) were significantly related to the severity of diabetic retinopathy (P < 0.025, trend test). The mean ratio of VIII:C/VIIIR:ag was lower in the diabetics with proliferative retinopathy than in the other groups of diabetics (P < 0.05) or the controls (P < 0.02). Concentrations of .alpha.2 macroglobulin and .alpha.1 antitrypsin were highest in diabetics with proliferative retinopathy (0.1 > P > 0.05, trend test) but mean prothrombin and activated partial thromboplastin times and mean concentrations of .alpha.2 antiplasmin, plasminogen activator and antithrombin III were similar in all groups. Concentrations of the platelet-specific protein .beta.-thromboglobulin, though higher in diabetics than controls (P < 0.005), were not related to retinopathy. The plasma concentrations of coagulation factors did not correlate with creatinine clearance and there were no significant differences between groups in concentrations of C-reactive protein; this suggests that the raised concentrations of coagulation factors in diabetics with retinopathy were not a result of associated nephropathy or an acute phase protein response to diabetic tissue damage. Increased coagulation activity in diabetics may contribute to the development of retinopathy.