Chronic progressive changes in brachial and carotid artery circulations under the combined effects of aging and hypertension.

Brachial and carotid artery diameters, blood velocities and blood flows were determined by a pulsed-Doppler flowmeter in 22 normotensive and 74 mild to moderate essential hypertensive subjects, aged 46 +/- 8 years. The product age x MAP/1000 (where MAP is mean arterial blood pressure), called 'arterial age' (expressed in years x mmHg/1000), was used to assess the progress of age and blood pressure. The moving-mean method was first used to explore the chronic hemodynamic changes in the two circulations with a progressive increase in arterial age. The method indicated that an arterial age of about 4-4.5 units a noticeable decrease in both brachial and carotid blood velocities occurred, and at an arterial age of about 5 units an important increase in brachial artery diameter occurred. In order to test these findings, the total sample (n = 96) was divided into three groups of equal size with low, median and high arterial ages. Brachial blood velocity decreased significantly in groups 2 (P less than 0.05) and 3 (P less than 0.05) compared with group 1, and carotid blood velocity decreased significantly from group 1 to group 2 (P less than 0.02) and from group 2 to group 3 (P less than 0.05). Brachial artery diameter did not change from group 1 to group 2, but increased significantly from group 2 to group 3 (P less than 0.05). Over the whole arterial age range, the carotid artery diameter remained identical.(ABSTRACT TRUNCATED AT 250 WORDS)