DOES VITAMIN-D STRENGTHEN THE INCREASE IN FEMORAL-NECK BMD IN OSTEOPOROTIC WOMEN TREATED WITH ESTROGEN

The long-term effects on bone of estrogen therapy (HRT) combined with vitamin D-3 supplementation were evaluated and compared with the effec ts of HRT without vitamin Dg supplementation in a 4-year prospective, partly randomized study among 60 osteoporotic women (mean age 55.4 yea rs; range 49.7-59.3 years). The women studied were a subgroup of the p opulation-based Kuopio Osteoporosis Risk Factor and Prevention Study ( OSTPRE) (n = 13100). The bone mineral densities (BMD) of the lumbar sp ine and femoral neck were determined by dual-energy X-ray absorptiomet ry (DXA) in 3236 perimenopausal women. Those 106 women with baseline B MD more than 2 SDs less than the mean value in this population, either at the lumbar spine (BMD <0.826 g/cm(2)) and/or femoral neck (BMD <0. 684 g/cm(2)), were offered treatment for osteoporosis. After exclusion s, 60 women were included in the analyses. Group allocation was: HRT ! estradiol valerate (2 mg) plus cyproterone acetate, 1 me, sequentially : Climen(R)) (n = 21); HRT + Vit D: Climen + vitamin D-3 (cholecalcife rol, 300 IU/day, no intake during June-August) Cn = 23); controls: 16 women who refused all treatment served as a non-randomized control gro up. In the HRT, group, the highly significant increase in lumbar BMD w as 5.4%, 5.3%, 4.7% and 4.0 after 1, 2, 3 and 4 years of treatment, re spectively, all compared with the baseline values and with the control group. The increase in femoral neck BMD was statistically insignifica nt (1.4%, 2.2%, 1.9% and 2.1%, respectively; p>0.05). In the HRT + Vit D group, the lumbar BMD increased by 3.7%, 4.9%, 4.9% and 4.9% (p<0.0 01), whereas the 5.8% increase in femoral reached significance at 3 ye ars compared with the control group as well as with the baseline value s. However, there were no statistically significant differences in lum bar or femoral BMD changes between the two HRT groups. In conclusion, estrogen can substantially increase lumbar bone mass in patients with postmenopausal osteoporosis. In addition, the combination of HRT and v itamin D-3 may increase femoral neck BMD in osteoporotic women more th an estrogen alone.