The fluid phase of coagulation and the accelerated atherosclerosis of diabetes mellitus.

The early and accelerated atherosclerosis associated with diabetes mellitus is probably multifactorial in origin. Hyperglycemia, in addition to its numerous pathologic effects on lipids, hormonal profiles, the vascular tree, and platelets, is also associated with effects on the fluid phase of coagulation. The most striking abnormality of coagulation described in diabetes mellitus is a decrement in fibrinogen survival that is rapidly reversible with correction of hyperglycemia or the administration of heparin but not with aspirin and dipyridamole administration, suggesting a hypercoagulable state. Abnormalities of clotting factor assays and circulating levels have been reported in patients with diabetes mellitus, but most of these studies are complicated by the controversy over the results being due to diabetes mellitus or due to the presence of vascular lesions concomitant with diabetes. Nevertheless, an increasing amount of evidence implicates the participation of the fluid phase of coagulation in both the initiation and propagation of diabetic vascular complications.