['To determine whether smoking affects the endothelial function of young ED patients with no cardiovascular disease.', 'This study included 69 ED patients (21 smokers and 48 non-smokers) and 16 age-matched normal healthy controls. All underwent measurement of brachial artery flow-mediated vasodilation (FMD) and examinations of blood pressure, cholesterol, triglycerides and glucose.', 'Brachial artery FMD was remarkably decreased in the ED patients, even more significantly in the smokers ([6.0 +/- 0.8]%) than in the non-smokers ([9.7 +/- 2.5]%) (P < 0.05), as compared with that in the normal healthy controls ([14.0 +/- 2. 5]%, P < 0.05).'] Does [ Smoking impair endothelial function in ED patients ]?