Reduced endothelium-dependent peripheral vasodilation in the aged

Endothelial dysfunction may be present years before the clinical manifestations of atherosclerosis, which is particularly frequent in the late decades of life. Therefore, we have evaluated the presence of endothelial dysfunction in the elderly by measuring, by echo-Doppler technique, the vasodilatation of brachial artery in response to the hyperemia following forearm occlusion and decompression, a response that is dependent on endothelial function. We studied 10 subjects > 65 years (mean 72 +/- 8) and 10 subjects < 65 years (mean 40 +/- 6) all without clinical signs and without risk factors for atherosclerosis. The increase in brachial arterial flow during reactive hyperemia was similar in the young and elderly subjects (152 +/- 74% vs 129 +/- 63%, NS). While in the young at peak hyperemia we found a significant increase in brachial artery diameter from 3.4 +/- 0.9 to 4.1 +/- 1.0 mm (p < 0.005), there was no significant change in the elderly (from 3.0 +/- 0.7 to 3.1 +/- 0.7 mm, NS). In both groups sublingual glyceryl trinitrate produced a significant increase in brachial artery diameter (from 3.0 +/- 0.7 to 3.5 +/- 0.8 mm in the elderly, p < 0.01, and from 3.4 +/- 0.9 to 3.9 +/- 0.9 mm in the young subjects, p < 0.01, NS among groups), showing the absence in the elderly of structural vascular changes potentially responsible for absence of dilatation. In conclusion, elderly subjects without clinical signs or risk factors for atherosclerosis have a vascular endothelial dysfunction that may play an important role in pathologic processes of the cardiovascular system in the late decades of life.