Letter to the Editor: “Steroid Sex Hormones, Sex Hormone-Binding Globulin, and Diabetes Incidence in the Diabetes Prevention Program” by Mather K.J., et al

摘要

Using a population with elevated diabetes risk, the Diabetes Prevention Program cohort, Dr Mather et al (1) observed a cross-sectional association between circulating estrogens (estradiol and estrone) and 2-hour blood glucose in men. They also found a prospective association between estrogen and incident diabetes in men. The first interpretation of this study is that estrogen at higher physiological concentrations promotes insulin resistance and thus predisposes to diabetes in men. However, such an association does not necessarily imply causality. Indeed, in men, physiological concentrations of estrogen are antidiabetic. Men with total estrogen deficiency caused by a mutation of the CYP19 gene, which codes for the aromatase enzyme, have no circulating estrogen and develop insulin resistance, glucose intolerance, and even type 2 diabetes (2-4). These alterations are reversed by estrogen replacement therapy.