[Activity of the coagulation and fibrinolysis in non-insulin-dependent diabetes mellitus. In vivo study]. / Attività della coagulazione e della fibrinolisi in corso di diabete mellito insulino indipendente. Uno studio in vivo.

In vivo study of blood coagulation and fibrinolysis activities in non insulin dependent diabetes mellitus. The aim of the study was to investigate in vivo blood coagulation and fibrinolysis activities in a group of diabetic patients NIDDM with and without vascular complications. For this purpose we determined two sensitive indicators in vivo of blood coagulation and fibrinolytic activities such as fibrinopeptide A and B beta 15-42 respectively. Moreover, we computed the ratio between B beta 15-42 and fibrinopeptide A in order to investigate a possible imbalance in vivo between blood coagulation and fibrinolysis. Control groups were 15 healthy subjects and 28 non diabetic patients affected by atherosclerotic disease. Fibrinopeptide A and B beta values were significantly higher in the diabetic patients than controls but there was no difference between the former group and the atherosclerotic patients. Also, no correlation was found for FPA, B beta, B beta/FPAr and HbAlc, fructosamine and blood glucose levels. There was no difference in B beta, FPA and B beta/FPAr values for patients treated with insulin and for those treated with either hypoglycemic agents or diet. Our data indicate that in diabetic patients fibrinolysis activity is increased, but it cannot counterbalance thrombin activity which appears much more enhanced. Finally, the lack of correlation for FPA, B beta, B beta/FPAr and HbAlc, fructosamine and blood glucose suggests that blood coagulation and fibronolysis abnormalities are not related to the degree of blood glucose control.

Thrombin activity and oral anticoagulant therapy: a preliminary study.

The aim of this work was to investigate whether the thrombin activity is related to the degree of anticoagulation induced by oral anticoagulants. Moreover, we tried to detect an optimal anticoagulation range at which the lowest possible thrombin activity can be reached. We investigated 28 patients (19 women and 9 men, mean age 54 +/- 9 years). Anticoagulation had been induced by acenocoumarol for at least 1 year before the beginning of this study. The degree of anticoagulation was monitored by the thrombotest coagulation method. The therapeutic range was 5-13%. The thrombin activity was measured by means of the fibrinopeptide A radioimmunological assay. In 15, 7, and 6 of the patients, thrombotest and fibrinopeptide A were carried out twice, once, and three times, respectively. Our results show first of all a significant positive relationship between thrombotest and fibrinopeptide A (p less than 0.001). Once this result was obtained, we tried to improve our identification of the behaviour of the thrombin activity in relation to the degree of anticoagulation assessed by thrombotest. For this purpose we employed a third-degree polynomial regression analysis which showed a better fit of the data. Since the curve became steeper from about 10% thrombotest levels, we divided the FPA values on the basis of thrombotest ranges. FPA values for the 14- to 25% thrombotest range were significantly different from those in the thrombotest range of 4-10%. Moreover, FPA levels in the 11 to 13% thrombotest range were significantly different from those in the thrombotest range of 4-10%. Our results suggest that a significant decrease in thrombin activity may be achieved only with a deep anticoagulation.

Evidence for a relationship between high fibrinogen levels and decreased thrombin activity in vivo in elderly subjects.

In order to investigate whether high fibrinogen levels were associated with elevated thrombin activity, we measured fibrinogen and fibrinopeptide A in 37 elderly healthy subjects ranging from 60 to 93 years. Fibrinogen levels (519.1 +/- 127.0 mg/dl) and fibrinopeptide A (5.9, 0.9-18.1 ng/ml) were significantly higher than in younger controls. A highly significant negative linear correlation was found between fibrinogen and fibrinopeptide A in the elderly subjects (p less than 0.01). However, a polynomial regression showed that this negative relationship was present at the fibrinogen levels ranging between 420 and 700 mg/dl. Our results suggest that high fibrinogen levels in elderly subjects do not necessarily mean that their thrombin activity is concomitantly increased.

Relationship between elevated fibrinopeptide A levels and alpha-2-antiplasmin.

In order to investigate whether alpha 2-antiplasmin (alpha 2-AP) levels may be related to thrombin activity, we measured alpha 2-AP and fibrinopeptide A (FPA) in 51 patients with clinical conditions frequently associated with increased thrombin activity. The diagnoses were: atherosclerotic disease, chronic inflammatory disease and hematological neoplastic disease. A significant negative correlation was found between alpha 2-AP and FPA (p less than 0.01). When patients were divided into three subgroups on the basis of their FPA levels, a significant reduction in alpha 2-AP was found in patients with the highest FPA concentration (greater than 9 ng/ml). Accordingly, a significant negative relationship between alpha 2-AP and FPA was found only in this subgroup (p less than 0.01). Our data suggest that the partial consumption of alpha 2-AP in patients with elevated FPA levels may reflect a subclinical fibrinolysis activation secondary to increased thrombin activity.