Levels of three hemostatic factors in relation to serum lipids. Monocyte procoagulant activity, tissue plasminogen activator, and type-1 plasminogen activator inhibitor.

To explore the relationship between blood lipid levels and a predisposition to thrombosis, levels of three hemostatic factors were measured in 41 human subjects and correlated with serum lipids. Procoagulant activity associated with peripheral blood monocytes isolated and purified after a 2-hour incubation in whole blood was not significantly related to lipid levels. However, activity in monocytes incubated with 100 ng/ml of bacterial endotoxin was significantly correlated with high density lipoprotein (HDL) cholesterol (r = 0.55, p less than 0.005), while net procoagulant activity (endotoxin-challenged minus basal) was significantly correlated with both HDL cholesterol (r = 0.61, p less than 0.005) and total cholesterol (r = 0.50, p less than 0.01). Plasma levels of the fibrinolytic factor, tissue plasminogen activator, were significantly correlated with total cholesterol (r = 0.41, p less than 0.01), while those of the type-1 plasminogen activator inhibitor were significantly correlated with both total cholesterol (r = 0.46, p less than 0.01) and total triglycerides (r = 0.31, p less than 0.05). The balance between the fibrinolytic factors was not significantly related to serum lipids. These results suggest that the expression of procoagulant activity by peripheral blood monocytes exposed to endotoxin may be enhanced in cases where HDL cholesterol levels are high. In addition, these results suggest that hypertriglyceridemia may be associated with a decreased fibrinolytic capacity due to elevated secretion of plasminogen activator inhibitor.