[Right or wrong of the hormone replacement therapy involving osteoporosis]

Hormone Replacement Therapy (HRT) is replacement of depleted endogenous estrogen for postmenopausal women. Usually progestin is used in combination to avoid endometrial proliferation. As for bone metabolism, estrogens exert bone protective effect through inhibition of bone absorption. HRT has been shown to improve bone mineral density and to lower the risk of osteoporotic bone fracture. However, recent clinical studies proved that HRT not only raise the risk of breast cancer, but also increase the incidence of atherosclerotic cardiovascular diseases. Other than the treatment of postmenopausal vasomotor symptoms, the benefit of HRT is thought to be hard to outweigh its risk. To resolve this problem, low dose HRT and SERM (Selective Estrogen Receptor Modulator) regimens are under investigation. The evidences of androgen replacement for aged men are not accumulated enough to verify its effects and long term safety.