PLASMINOGEN-ACTIVATOR INHIBITOR ACTIVITY IN VARIOUS TYPES OF ENDOGENOUS HYPERTRIGLYCERIDEMIA

In various groups of patients, plasminogen activator inhibitor (PAI), plasma insulin and triglyceride level are closely associated all together. To clarify this relationship we looked at PAI activity in patients with endogenous hypertriglyceridemia, 15 were obese (body mass index (BMI) higher than 27, mean: 36.2), 9 had a strictly normal weight (BMI lower than 25, mean: 22.8) and 11 had alcohol induced hypertriglyceridemia. They were compared to 20 control subjects of normal weight and with plasma triglyceride level lower than 1. 7 mmol/l and 11 hypercholesterolemic patients. Overall mean PAI levels in hypertriglyceridemic patients were higher than in controls and hypercholesterolemic subjects. Compared to controls (mean+/-SD PAI: 9.8+/-5.4 U/ml), both PAI activity (30+/-12 U/ml p<0.05) and plasma insulin were elevated in obese hypertriglyceridemic patients but not different from normal in the normal weight hypertriglyceridemic patients (PAI activity 15.2+/-4.1 U/ml ns). In alcoholic hypertriglyceridemic patients, PAI activity was elevated (21+/-9.7 U/ml p<0.05) but insulin was normal. In the whole series PAI activity was weekly correlated with triglyceride level (r=0.295 p<0.05), but in strong positive relationship with insulin levels (r=0.572 p<0.0001). These results suggest that in obese patients insulin resistance is the common cause of both hypertriglyceridemia and elevation of PAI activity. Other mechanisms have to be looked for in some conditions such as alcohol associated hypertriglyceridemia. Endogenous hypertriglyceridemia occurring in strictly normal weight subjects is not accompanied by elevated PAI levels.