Summary
Fibrinogen is an independent risk factor for cardiovascular disease and both D-Dimer
and Thrombin-Antithrombin complexes may be suitable as laboratory markers of deep
venous thrombosis and are becoming more widespread in clinical practice. The aim of
our study was to evaluate their normal range and to examine their correlation with
various cardiovascular risk factors. Fibrinogen, D-Dimer and Thrombin-Antithrombin
complexes were assessed in 516 normal subjects randomly selected from the National
Health Service register of Trieste (Italy). In our community the mean value of fibrinogen
was 283 ± 71 mg/dl. Fibrinogen increases with age in males and was significantly higher
in male smokers. In non-smokers, females had significantly higher fibrinogen values
than males. The mean value of D-Dimer was 306 ± 130 ng/ml. In females it is significantly
higher. The fibrinogen and D-Dimer correlation coefficient was 0.20 (p < 0.001). The
mean level of Thrombin-Antithrombin complexes was 6.25 ±6.8 ng/ml with a distribution
markedly skewed towards the left; males had lower concentration than females (p =
0.047). Multiple regression analysis for fibrinogen as a dependent variable showed
that D-Dimer, LDL- eholesterol, Body-Mass Index and Thrombin-Antithrombin complexes
were poor predictors for fibrinogen plasma levels (R2 = 0.23) and that fibrinogen, ApoAl and age can explain only about 10% of the observed
variability in D-Dimer.