Hormone Replacement Therapy and Risk of Hip Fracture: Population Based Case – Control Study.
Michaelson K, for the Swedish Hip Fracture Study Group (Univ Hosp, Uppsala, Sweden; Dartmouth Med School, Hanover, NH; Karolinksa Inst, Stockholm; et al). BMJ 316: 1858-1863, 1998.
Optimal fracture protection requires recent HRT use, although treatment can start several years after menopause. The protective effect increases with the duration of use. An estrogen-sparing effect is achieved when the regimen contains progestins.
Editorial comments: There is much useful clinical information in this large population based, case control epidemiology study. The data indicate that long-term use of postmenopausal HRT is necessary to optimally reduce the risk of hip fractures. Since hip fractures usually occur after age 70, women need to take estrogen at least to this age and older as protection against hip fracture disappears 5 years after stopping HRT. The data also demonstrated greater protection against hip fracture when a progestin was added to the estrogen.
Low Dose Estrogen and Calcium Have an Additive Effect on Bone Resorption in Older Women.
KM Prestwood, DL Thompson, AM Kenny, et al (Univ of Conn, Farmington; Univ of Heidelberg, Germany). J Clin Endocrinol Metab 84: 179-183, 1999.
For bone resorption, there is an additive effect of low dose estrogen and calcium. However, there was no effect in older women for bone formation. In older women, the combination of low dose estrogen plus calcium is likely to be more effective than either treatment alone.
Editorial comments: The results of this short-term study in which markers of bone metabolism were measured in older women suggest that the addition of calcium supplementation and vitamin D to estrogen replacement prevents bone resorption to a greater extent than the use of estrogen alone. Clinicians should encourage postmenopausal women to ingest between 1200 and 1500mg of calcium daily and 400 to 800 international units of vitamin D in addition to taking estrogen replacement for maximal prevention of bone loss.