The effect of age upon the coagulation system

Abstract

SYNOPSIS Factors V, VII, VIII, X, XI, and XII of the coagulation system, platelet count, and antithrombin III levels were assayed in 20 healthy volunteers aged 20-40 years and 61 elderly subjects aged 66-96 years whose skinfold thickness was also measured. Factors XI, XII, and antithrombin III levels tended to increase in women and decrease in men while factors X, VII, and V tended to increase in both males and females with advancing years. No age or sex differences were found in platelet counts or factor VIII levels. Factor VIII levels were inversely correlated with obesity in elderly males (r = -0-56, P < 0-005).

Aging-associated changes in indices of thrombin generation and protein C activation in humans. Normative Aging Study.

“…In a subgroup of 53 patients with F1+2 measurements that were either > 2.5 nM (mean F1+2, 3 It therefore appears that a cohort of older males exhibits hemostatic system hyperactivity either on the basis of suppression of the endogenous heparin-antithrombin III mechanism without reduction in plasma concentration of the protease inhibitor, or excessive generation of Factor Xa that cannot be contained by this mucopolysaccharide-dependent natural anticoagulant mechanism. The decreased activity of the heparin-antithrombin III mechanism could be secondary to low levels of vessel wall heparinlike substances and/or more effective competition between blood components and antithrombin III for the limited quantities of endothelial cell glycosaminoglycan.…”

“…The major difficulty encountered in unravelling this puzzle has been a lack of reliable techniques for quantifying pertinent changes in blood coagulability. It should be noted that previous methods for monitoring these processes have been directed at measuring the levels of zymogens, inhibitors, or substrates of the hemostatic system (1)(2)(3)(4)(5). Unfortunately, these molecular species are present in large excess within the blood.…”

Genetic and Molecular Mechanisms of Age Regulation (Homeostasis) of Blood Coagulation

“…Blood coagulation potential in humans reaches the value seen in young adults before puberty, then gradually increases through adulthood, reaching a value almost twofold higher by old age (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17). This age-associated increase takes place even in healthy centenarians (18).…”

Genetic Mechanisms of Age Regulation of Blood Coagulation

“…1 Blood coagulation potential in humans as well as other mammals reaches a young adult level around the time of weaning, followed by a gradual increase during young adulthood and an almost 2-fold increase by old age. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] This advancing age-associated increase in coagulation potential takes place in healthy centenarians, 18 indicating that the increase is a normal age-associated phenomenon. However, it is conceivable that in the general human population, such increases in blood coagulation potential may substantially contribute to the development and progression of ageassociated cardiovascular and thrombotic disorders.…”