Hormone replacement therapy in postmenopausal women with diabetes mellitus: a risk-benefit assessment

Hormone replacement therapy (HRT) has been shown to be beneficial in reducing osteoporosis and alleviating climacteric symptoms. HRT has been suggested to reduce the risk for coronary heart disease (CHD), but data are controversial. Unopposed estradiol therapy seems to have a favourable effect on lipid profile and glucose tolerance whereas addition of a progestogen may attenuate these favourable metabolic changes. Data on HRT in women with diabetes mellitus are scarce but of potential interest since these women are often characterised by hyperandrogenicity, insulin resistance and dyslipidaemia and are at a high risk for developing CHD. Present evidence suggests that short term unopposed oral estradiol therapy has a beneficial effect on glucose homeostasis, lipid profile and fibrinolytic activity, which may be compatible with a reduced risk for CHD. Accordingly, it may be hypothesised that HRT in women with diabetes mellitus may be at least as beneficial as in women without diabetes mellitus. However, women with diabetes mellitus are at increased underlying risk for venous thromboembolism and endometrial cancer. Whether HRT further increases this risk is not yet clear, but this possibility must be considered. It is, however, likely that the benefits with HRT in postmenopausal women with diabetes mellitus outweigh the risks, but randomised studies are required before any more definite risk-benefit assessment can be made long term.