Osteoporosis postmenopausal hormone therapy

The most frequent uses of estrogens are for contraception (see p. 268), for postmenopausal hormone therapy and for osteoporosis. Estrogens are also used extensively for replacement therapy in patients deficient in this hormone. Such a deficiency can be due to lack of development of the ovaries, menopause, or castration. 

Estrogen-based postmenopausal hormone therapy should be used for the treatment of menopausal symptoms (i.e., vasomotor and urogenital symptoms) and, when specifically indicated, for osteoporosis prevention. 

During the past decade, postmenopausal hormone therapy became one of the most frequently prescribed therapies in the United States. Menopause is a natural life event, not a disease. Therefore, the decision to use hormone therapy must be individualized based on the severity of menopausal symptoms, risk of osteoporosis, and consideration of such factors as coronary artery disease, breast cancer, and thromboembolism. 

Alternatives to steroid hormone therapy for osteoporosis include raloxifene, bisphosphonates, sodium fluoride, vitamin D and calcium supplementation, calcitonin, and parathyroid hormone. Tamoxifen has estrogenic effects on bone and delays bone loss in postmenopausal women. However as a result of estrogenic activity in the uterus, long-term tamoxifen administration has been associated with an increased risk of... 

Gambacciani M, Vacca F. Postmenopausal osteoporosis and hormone replacement therapy. Minerva Med. 2004 95 507-520. 

PRINCE R L, SMITH M, DICK I M, PRICE R I, WEBB P G, HENDERSON N K and HARRIS M M (1991) Prevention of postmenopausal osteoporosis. A comparative study of exercise, calciiun supplementation, and hormone-replacement therapy. N Eng J Med 325, 1189-95. 

Wells G, Tugwell P, Shea B, Guyatt G, Peterson J, Zytaruk N, Robinson V, Henry D, O Connell D, Cranney A (2002) Meta-analyses of therapies for postmenopausal osteoporosis. V. Meta-analysis of the efficacy of hormone replacement therapy in treating and preventing osteoporosis in postmenopausal women. Endocr Rev 23 529-539... 

Estrogens are most commonly used as a component of combination contraceptives or as hormone replacement therapy in postmenopausal women. Benefits in postmenopausal women include relief of moderate to severe vasomotor symptoms and decreased risk of osteoporosis. Hormone replacement therapy also may be used in vaginal and vulvar atrophy and in hypoestrogenism caused by hypogonadism, castration, or primary ovarian failure. Less commonly, select breast or prostate cancer... 

Optimal management of the postmenopausal patient requires careful assessment of her symptoms as well as consideration of her age and the presence of (or risks for) cardiovascular disease, osteoporosis, breast cancer, and endometrial cancer. Bearing in mind the effects of the gonadal hormones on each of these disorders, the goals of therapy can then be defined and the risks of therapy assessed and discussed with the patient. 

Cranney A, Wells GA. Hormone replacement therapy for postmenopausal osteoporosis. Clin Geriatr Med 2003 19 361-70. 

Estradiol (valerate) Estradiol + norethindronate (acetate) Estradiol (valerate ) + levonorgestrel Hormone-replacement therapy in estrogen-deficiency symptoms and prevention of osteoporosis in postmenopausal women... 

Hormone replacement therapy (HRT), including tibolone, is not recommended for postmenopausal women over the age of 50 years unless other treatments for osteoporosis are contraindicated or not tolerated (MHRA, 2005). 

The polypeptide parathormone is released from the parathyroid glands when the plasma Ca2+ level falls. It stimulates osteoclasts to increase bone resorption in the kidneys it promotes calcium reabsorption, while phosphate excretion is enhanced. As blood phosphate concentration diminishes, the tendency of Ca2+ to precipitate as bone mineral decreases. By stimulating the formation of vitamin D hormone, parathormone has an indirect effect on the enteral uptake of Ca2+ and phosphate. In parathormone deficiency, vitamin D can be used as a substitute that, unlike parathormone, is effective orally. Teriparatide is a recombinant shortened parathormone derivative containing the portion required for binding to the receptor. It can be used in the therapy of postmenopausal osteoporosis and promotes bone formation. While this effect seems paradoxical in comparison with hyperparathyroidism, it obviously arises from the special mode of administration the once daily s.c. injection generates a quasi-pulsatile stimulation. Additionally, adequate intake of calcium and vitamin D must be ensured. 

Idiopathic osteoporosis cannot be prevented by prophylactic therapy, but its development can be delayed. This requires a healthy lifestyle with plenty of physical exercise (sports, hiking), daily intake of calcium (lOOOmg/day Ca2+) and of vitamin D (1000 IU/day). The same principle holds for postmenopausal osteoporosis. Hormone Luellmann, Color Atlas of Pharmacology All rights reserved. Usage subject to terms... 

Ringe JD, Setnikar 1. Monofluorophosphate combined with hormone replacement therapy in postmenopausal osteoporosis. An open-label pilot efficacy and safety study. Rheumatol Int 2002 22(l) 27-32. 

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