ARTERIAL STIFFENING - OPPOSING EFFECTS OF AGE-ASSOCIATED AND HYPERTENSION-ASSOCIATED STRUCTURAL-CHANGES

This article reviews the effects of aging and hypertension on geometri cal (lumen and arterial wall thickness) and functional (distensibility ) properties of large and medium-sized arteries in humans. Several cli nical and animal studies show that arterial wall hypertrophy does not increase the elastic modulus of the arterial wall material during sust ained essential hypertension. The structural changes associated with e ither hypertension or aging have opposing effects on arterial distensi bility, under similar transmural conditions: the former increasing it, the latter decreasing it. Thus, hypertension cannot be assimilated to aging. The structural and functional changes of the arterial wall mat erial that are associated with the hypertension-induced hypertrophy co uld be a means by which medium-sized arteries maintain their distensib ility characteristics despite increased distending pressure, and large arteries compensate for the age-induced decrease in arterial complian ce.