Age-dependency in molecular markers of haemostasis, fibrinolysis and in soluble adhesion molecules

Objective: Elevation of several molecular markers of the haemostatic/fibrinolytic system and of soluble adhesion molecules has been associated with acute or chronic phases of atherosclerosis. Speculating that markers associated with atherosclerosis would increase with age, we determined the age-dependency of some of these markers in clinically healthy individuals. Methods: 129 healthy persons were enrolled [division: younger (≤34 years)/older group (>34 years)]. Tissue-type plasminogen activator (t-PA) concentration, plasmin/α2-antiplasmin complex (PAP), D-dimer (DD), prothrombin fragment F1+2 (F1+2), thrombin-antithrombin III complex (TAT), soluble (sICAM-1) intercellular adhesion molecule-1, soluble (sVCAM-1) vascular cell adhesion molecule-1 and sP-selectin were measured with enzyme-linked immuno assays, plasminogen activator inhibitor-1 (PAI-1), plasma kallikrein-like activity (KK), and factor XII (FXII) with chromogenic substrate tests, fibrinogen with the Clauss method. Results: Fibrinogen (P < 0.01), F1+2 (P<0.01), KK (P<0.05) were significantly higher in the older vs. the younger group and correlated significantly with age (P<0.05, P<0.01). DD showed significantly higher values in the older vs. the younger group, whereas T-PA, PAP, FXII, TAT did not. PAI-1 tended towards higher values in the older vs. the younger persons. T-PA, PAI-1, DD correlated significantly with age P-selectin, sICAM-1, sVCAM-1 did not differ between both groups, nor could a significant age-dependency be found. Conclusion: This study indicates that plasma levels of several molecular markers of the haemostatic and fibrinolytic system increase with age. The age-dependency of these markers has to be taken into account in respect to their clinical use in order to characterize patients with suspected risk of atherosclerotic events.