RELATIONSHIPS OF INSULIN AND INTACT AND SPLIT PROINSULIN TO HEMOSTATIC FUNCTION IN YOUNG MEN WITH AND WITHOUT CORONARY-ARTERY DISEASE

Glucose intolerance, hyperinsulinaemia, dyslipoproteinaemia and multip le disturbances of haemostatic function are characteristics of young m en with premature coronary artery disease. The relations between gluco se, insulin and insulin propeptides, in the fasting state, and after a n oral glucose load, and haemostatic function were examined in 62 cons ecutive non-diabetic men with myocardial infarction before the age of 45 and in 41 age-matched healthy men. ''True'' hyperinsulinaemia, rais ed plasma concentrations of insulin propeptides, dyslipoproteinaemia, elevated plasma levels of fibrinogen, factor VII antigen (Wag) and pla sminogen activator inhibitor-1 (PAI-1) activity, and lower antithrombi n activity (p <0.05-0.001) characterized the patients. PAI-I activity was more closely associated with insulin, intact proinsulin and des 31 ,32proinsulin in patients than in controls, whereas the plasma levels of fibrinogen, activated factor VII (VIIa) and VIIag were stronger cor related with insulin and insulin propeptides in subjects without coron ary artery disease. Very low density lipoprotein (VLDL) triglyceride w as a strong determinant of Wag and PAI-1 activity levels in both cases and controls, whereas VLDL triglyceride in controls and LDL cholester ol in patients related significantly to the plasma fibrinogen concentr ation. Thus, our data suggests that plasma insulin and insulin propept ides might be involved in the regulation of plasma fibrinogen concentr ation, factor VII level and plasma PAI-1 activity. However, apolipopro tein B-containing lipoproteins appear to influence the relationships b etween insulin, insulin propeptides and haemostatic factors in individ uals with premature coronary artery disease.