Endogenous testosterone and brachial artery endothelial function in middle-aged men with symptoms of late-onset hypogonadism

Abstract

In aging men, serum endogenous testosterone is inversely associated with common carotid intima-media thickness (IMT) and directly with beneficial plasma lipid levels; however, the relationship to endothelial function is poorly characterized. We examined the association between serum testosterone and endothelium-dependent brachial artery flow-mediated dilatation (FMD) in middle-aged to elderly men. A group of 83 men aged 4069 years (mean 55.9±7.5 [SD]) with andropausal symptoms were studied. We measured their serum lipids, testosterone, luteinizing hormone, mean carotid IMT and brachial artery FMD by high resolution B-mode ultrasound. Brachial FMD correlated inversely with vessel diameter (r=-0.38, p=0.0004), alcohol consumption (r=-0.22, p=0.047) and serum testosterone (r=-0.27, p=0.01), but not with luteinizing hormone. In multivariate analysis, FMD was explained by testosterone (β=-0.17, p=0.0226), high density lipoprotein cholesterol (β=4.17, p=0.0312) and vessel diameter (β=-4.37, p<0.0001) when adjusted for age, body mass index, triglycerides, blood pressure, carotid IMT, smoking, alcohol consumption, cardiovascular diseases and use of lipid lowering medication (HMG-CoA reductase inhibitors). In middle-aged to elderly men, there is an inverse correlation between serum testosterone and brachial FMD. These data suggest that testosterone may have an adverse effect on systemic endothelial function. © 2011 Informa UK, Ltd.