It has been suggested that impaired fibrinolytic-coagulation system, such as increased concentration of inhibitors to fibrinolysis or activators to coagulations, occasionally may play a role in the development of atherosclerotic vascular disease. In this study, we aimed to elucidate the relationship of serum lipids to fibrinolytic-coagulation system. The subjects studied were 190 outpatients at Kyorin University Hospital, 108 of whom were mostly hypertension, diabetes mellitus and hyperuricemia (Control), 59 of whom were coronary heart disease (CHD), 25 of whom were cerebrovascular disease (CVD). Blood samples were measured the levels of blood coagulation factors VII (F-VII) and X (F-X), and plasminogen activator inhibitor-1 (PAI-1) in these subjects, together with the concentrations of serum lipids. The serum levels of F-X was significantly higher in CHD subjects than in controls (111 +/- 19% vs 101 +/- 22%, p < 0.05). However, there was a no significant difference of F-VII among three groups. And we found that the levels of serum lipids, especially serum triglycerides showed a significant positive correlation between the concentrations of F-VII (r = 0.343, p < 0.01) and F-X (r = 0.513, p < 0.01), and PAI-1 (r = 0.528, p < 0.001) in CHD and CVD subjects. For this reason, 156 bank employee subjects were also admitted to this study (Bank employees). In bank employee subjects, the serum levels of triglycerides also showed a significant positive correlation with the levels of F-VII (r = 0.321, p < 0.001), F-X (r = 0.254, p < 0.001) and PAI-1 (r = 0.420, p < 0.001). These data suggest that serum lipids, particularly triglycerides have a close relationship with thrombogenesis as evidenced by activated F-VII and F-X in the extrinsic coagulation system and also by elevated PAI-1 activities in fibrinolysis. Therefore, when we try to prevent the patients from CHD or treat them, we ought pay attentions not only to serum cholesterol or LDL-cholesterol for their atherogenic actions, but also to triglycerides because of their close correlation with extrinsic coagulation system and anti-fibrinolytic activities. The reduction of fibrinolytic capacity due to increased plasma levels of F-VII, X and PAI-1 may have importance in atherosclerotic vascular disease, particularly in patients with hypertriglyceridemia.