Thrombin and plasmin activity in diabetes mellitus and their association with glycaemic control.

Abnormalities of haemostasis are common in diabetes mellitus. As indicators of fibrinolysis and coagulation, plasmin and thrombin activity were assessed by assay of the fibrinogen peptide derivatives B beta 15-42 and fibrinopeptide A respectively in 60 diabetic patients and 50 control subjects in a cross-sectional study. Glycosylated haemoglobin (HbA1) correlated with B beta 15-42 (r = -0.26, p less than 0.05) and fibrinopeptide A (r = 0.30, p less than 0.05) in the diabetic patients suggesting that poor glycaemic control (i.e. high HbA1 levels) was associated with depressed plasmin and enhanced thrombin activity. Compared to controls, fibrinopeptide A levels were increased in diabetics (p less than 0.001) irrespective of sex or type of diabetes. B beta 15-42 levels were normal in diabetic females but increased in diabetic men (p less than 0.001) possibly secondary to the activation of coagulation. These results suggest that in diabetes mellitus activation of coagulation is the dominant haemostatic abnormality and that better glycaemic control could influence in-vivo plasmin and thrombin activity favourably.