Plasma estrogens, androgens, and von Willebrand factor in men on chronic hemodialysis

The role of sex hormones in atherogenesis has not been well defined. Since hemodialysis patients show signs of feminization and an increased propensity for atherosclerosis they are particularly suited to probe the relationship between estrogen, testosterone, and atherosclerosis. Therefore, we measured plasma total, free, and protein-bound estradiol (E2), testosterone (Te), and prolactin in 28 hemodialysis patients and in 30 age-matched controls. Von Willebrand factor (vWF) levels were also assayed. Total and free E2 as well as Te were significantly decreased in the patients (p less than 0.001). However, the E2/Te ratio was elevated in the patients (p = 0.05), as was vWF (p less than 0.01). No correlations were found between hormone levels and vWF, gynecomastia or vascular disease, but vWF and vascular disease were highly correlated. We conclude that in hemodialysis patients absolute estrogen levels are lower than normal, but that the estrogen/androgen ratio is shifted in favor of estrogen because of the coexistence of androgen deficiency. These findings suggest that an elevation in the estrogen/androgen ratio, rather than an increase in estrogen per se, may be a risk factor for atherosclerosis.