Royal Prince Alfred Hospital, The Heart Research Institute, and University of Sydney, Camperdown NSW, Australia.
BACKGROUND: Passive smoking is associated with early arterial damage, but the potential for reversibility of this damage is unknown. OBJECTIVE: To assess the reversibility of arterial endothelial dysfunction, a key marker of early atherosclerosis. DESIGN: Cross-sectional study. SETTING: Academic medical center. PARTICIPANTS: 60 healthy persons 15 to 39 years of age: 20 with no exposure to active or passive smoking, 20 nonsmoking passive smokers (exposure to environmental tobacco smoke for > or = 1 hour per day for > or = 2 years), and 20 former passive smokers. MEASUREMENTS: Arterial endothelial function measured by noninvasive ultrasonography. RESULTS: Endothelium-dependent dilatation was significantly better in former passive smokers (5.1% +/- 4.1% [range, -1.2% to 15.6%]) than in current passive smokers (2.3% +/- 2.1% [range, -0.2% to 6.7%]) (P = 0.01), although both groups were significantly impaired compared with nonsmoking controls (8.9% +/- 3.2% [range, 2.1% to 16.7%]) (P < or = 0.01 for both comparisons). CONCLUSIONS: In healthy young adults, arterial endothelial dysfunction related to passive smoking seems to be partially reversible.