Erectile dysfunction as a generalized vascular dysfunction

Objective: We hypothesize that generalized vascular dysfunction may be the underlying cause in patients with erectile dysfunction (ED) without atherosclerosis and its major risk factors. Methods: In all, 30 outpatients with ED and 25 healthy volunteers as a control group were enrolled for this study. Aortic stiffness was calculated from data obtained by echocardiographic examination, which was performed using commercially available equipment with a 2.5- to 3.5-MHz transducer. Endothelium-dependent flow-mediated dilation (FMD) of the brachial artery was assessed using a high-resolution ultrasound system with a 10-MHz linear-array vascular transducer. Shear stress and nitroglycerin was used as a stimulus for assessing endothelium-dependent FMD and nonendothelium-dependent dilation of the brachial artery. Results: FMD was significantly decreased in the ED group compared with control group (4.1 +/- 3.1% vs 9.7 +/- 3.5%, P <.001). Nonendothelium-dependent dilation was statistically insignificant in patients with ED compared with control subjects (13 +/- 3.9% vs 15.4 +/- 3.8%, P =.55). The relationship between ED and FMD was significant (r = -0.66, P <.001), whereas no relationship was found between ED and nonendothelium-dependent dilation (r = -0.23, P >.05). Aortic strain (3.7 +/- 2.7% vs 9.5 3.2%, P <.001) and distensibility (1.5 +/- 1.0 vs 4.7 +/- 2.9 cm(2) dyne(-1).10(-3),p <.001) were found significantly lower in the ED group than in the control group. The relationship between ED and aortic stiffness was also significant (for aortic strain; r = - 0.62, P <.001 and for aortic distensibility; r = -0.60, P <.001). Conclusion: Aortic and brachial artery functions are impaired in men with ED without cardiovascular disease or its major risk factors, indicating a more generalized vascular disease.