Circulating sex hormones and breast cancer risk factors in postmenopausal women: reanalysis of 13 studies

Abstract

Background:Breast cancer risk for postmenopausal women is positively associated with circulating concentrations of oestrogens and androgens, but the determinants of these hormones are not well understood.Methods:Cross-sectional analyses of breast cancer risk factors and circulating hormone concentrations in more than 6000 postmenopausal women controls in 13 prospective studies.Results:Concentrations of all hormones were lower in older than younger women, with the largest difference for dehydroepiandrosterone sulphate (DHEAS), whereas sex hormone-binding globulin (SHBG) was higher in the older women. Androgens were lower in women with bilateral ovariectomy than in naturally postmenopausal women, with the largest difference for free testosterone. All hormones were higher in obese than lean women, with the largest difference for free oestradiol, whereas SHBG was lower in obese women. Smokers of 15+ cigarettes per day had higher levels of all hormones than non-smokers, with the largest difference for testosterone. Drinkers of 20+ g alcohol per day had higher levels of all hormones, but lower SHBG, than non-drinkers, with the largest difference for DHEAS. Hormone concentrations were not strongly related to age at menarche, parity, age at first full-term pregnancy or family history of breast cancer.Conclusion:Sex hormone concentrations were strongly associated with several established or suspected risk factors for breast cancer, and may mediate the effects of these factors on breast cancer risk.

Night shift work and other determinants of estradiol, testosterone, and dehydroepiandrosterone sulfate among middle-aged nurses and midwives

“…Sex hormones that serve essential functions in women's physiology are also known to play a role in the etiology of common diseases such as osteoporosis and bone fractures (1), breast cancer (2,3), and cardiovascular diseases (1). Both experimental and observational studies confirmed the role of estrogens in the etiology of breast cancer (4).…”

“…Body weight reflects adipose tissue, which is a source of estrogens and testosterone (50). For smoking, the suggested mechanisms may involve stimulation of hormones synthesis by the adrenal glands (2) through up-regulation of the hypothalamic-pituitary-adrenal axis (3). As for the physical activity, the changes in endogenous sex hormones may be related to modification of body weight (adiposity) (50).…”

MANAGEMENT OF ENDOCRINE DISEASE: Hyperandrogenism after menopause

“…Although the issue is still not settled, it seems prudent to suggest that the higher prevalence of adverse cardiometabolic risk factors in hyperandrogenic pre-and postmenopausal women does not seem to increase the prevalence of CVD and/or overall mortality (87,89,90,91). After menopause, androgen levels are positively associated with an increased breast cancer risk and other gynecological malignancies (32,92,93,94). The positive correlation of elevated endogenous androgen (testosterone and DHEAS) levels with postmenopausal breast cancer is more evident in estrogen receptor-positive breast tumors (95,96).…”

A simplified questionnaire for self-assessment of hirsutism in population-based studies

“…Furthermore, after a woman's reproductive years, various situations related to excess body hair may develop including hirsutism induced by obesity, ovarian hyperthecosis, and androgen-producing tumors (18,20). In addition, the clinical effects of hyperandrogenism alone or within the context of PCOS at this time of life may be related to atherogenesis, insulin resistance, breast cancer, or cardiovascular disease (21,22,23).…”