VITAMIN-D AND HRT - NO BENEFIT ADDITIONAL TO THAT OF HRT ALONE IN PREVENTION OF BONE LOSS IN EARLY POSTMENOPAUSAL WOMEN - A 2.5-YEAR RANDOMIZED PLACEBO-CONTROLLED STUDY

The study was designed to examine the effect of hormone replacement th erapy (HRT) and low-dose vitamin D (Vit D) supplementation on the prev ention of bone loss in non-osteoporotic early postmenopausal women and to determine whether Vit D supplementation can give additional benefi t to an already optimized estrogen regimen. The effects of HRT and Vit D on bone mineral density (BMD) were studied in postmenopausal women in a 2.5-year randomized placebo-controlled study. The study populatio n was a subgroup of the Kuopio Osteoporosis Risk Factor and Prevention Study (OSTPRE) (n = 13 100). A total of 464 early postmenopausal wome n were randomized to four groups: (1) HRT (a sequential combination of 2 mg estradiol valerate and 1 mg cyproterone acetate (E(2)Val/CPA); ( 2) vitamin D-3 (cholecalciferol, 300 IU/day); (3) HRT + Vit D; and (4) placebo (calcium lactate; 93 mg Ca2+/day). Lumbar (L1-4) and femoral neck BMD were determined by dual-energy X-ray absorptiometry before an d after 2.5 years of treatment. After 2.5 years, lumbar BMD had increa sed by 1.8% in the HRT group (p < 0.001) and by 1.4% in the HRT + Vit D group (p = 0.002), whereas lumbar BMD had decreased by 3.5% (p < 0.0 01) in the Vit D group and by 3.7% (p < 0.001) in the placebo group. T he loss of femoral neck BMD was lower in the HRT (-0.3%) and the HRT Vit D (-0.9%) groups compared with the Vit D (-2.4%) and the placebo groups (-3.7%). This study confirms the beneficial effect of HRT on BM D. It also shows that low-dose vitamin D supplementation has only a mi nor effect in the prevention of osteoporosis in non-osteoporotic early postmenopausal women and does not give any benefit additional to that of HRT alone.