A two-year double-blind study monitored and evaluated the effects of 1α-hydroxy vitamin D3 (1α(OH)D3) on the lumbar (L2-4BMD) and total body bone mineral densities (TBBMD) and occurrence of fracture in 113 female osteoporotic patients receiving 0.75μg/day of 1α(OH)D3 (n=57) or a placebo (n=56) with calcium supplementation in both groups. L2-4BMD increased 1.81% and 2.32% after one and 2 years in the 1α(OH)D3 group, but decreased 1.89% (P<0.05) and 0.28% in the placebo group. A significant difference (P<0.01) existed between the two groups after one year. TBBMD decreased significantly in the placebo group by 3.34% (P<0.01) and 3.52% after one and 2 years. Six new fractures occurred in the control group, but only two in the 1α(OH)D3 group (Odd's ratio=0.343, 95% confidence range; 0.0648-1.815). There were no serious adverse effects of the 1α(OH)D3 treatment. It was concluded that two-year treatment with 1α(OH)D3 increased the lumbar BMD and inhibited the decrease in TBBMD. Altough it was not significant, new fracture occurrence in the 1α(OH)D3 group was around 1/3 of that in the control group.
The Japan Endocrine Society