Systolic hypertension, arterial stiffness, and vascular damage: role of the renin-angiotensin system.

The field of hypertension is entering an exciting new era in which new concepts in basic and clinical science are being rapidly translated into new recommendations for clinical practice. It is now readily apparent that an age-related increase in stiffness of the walls of the large arteries causes the predominant hemodynamic characteristic of hypertension in later life: increased systolic blood pressure. Systolic hypertension is now recognized to have greater prognostic significance than diastolic hypertension, and it is also known that the effective treatment of systolic hypertension confers a proportional benefit in risk reduction. A rapidly advancing knowledge of vascular biology has revealed that the renin-angiotensin system plays a central role in the pathogenesis of vascular hypertrophy and arterial stiffness. Angiotensin-converting enzyme inhibitors have been shown to reduce arterial stiffness to a greater degree than diuretics or beta-blockers. The pharmacologic interruption of the renin-angiotensin system may therefore confer previously unrecognized benefits on age-related vascular damage, providing special benefits in systolic hypertension.