Gallagher J C, Riggs B L
Department of Bone Metabolism, Creighton University, Omaha, NE.
Metabolism. 1990 Apr;39(4 Suppl 1):30-4. doi: 10.1016/0026-0495(90)90269-i.
In postmenopausal osteoporotics, malabsorption of calcium is associated with reduced levels of serum 1,25-dihydroxyvitamin D. Metabolic studies have shown that calcium absorption can be normalized and calcium balance improved after administration of oral doses of synthetic 1,25-dihydroxyvitamin D3 (Rocaltrol) 0.25 micrograms twice daily. Further studies performed at two centers compared the effect of Rocaltrol 0.25 micrograms twice daily versus placebo on vertebral fracture rates in osteoporotics. A significant reduction in vertebral fracture rates was seen at the end of 1 year. Those patients who continued on Rocaltrol for a second and third year showed a progressive decrease in vertebral fractures. Rocaltrol, administered at a dose of 0.25 micrograms twice daily, seldom causes hypercalcuria or hypercalcemia in osteoporotic patients on a typical calcium intake of 700 to 800 mg/d. Careful measurements of renal function over a period of 3 years in patients treated with Rocaltrol, 0.25 micrograms twice daily, showed no deterioration in renal function. These data suggest that 1,25-dihydroxyvitamin D3 is a useful therapy in the management of patients with postmenopausal osteoporosis, particularly those who have malabsorption of calcium. We found that it improves calcium balance, reduces the vertebral fracture rate, and is safe to use provided that the dietary calcium is monitored and does not exceed 800 mg/d.
在绝经后骨质疏松症患者中，钙吸收不良与血清1,25 - 二羟维生素D水平降低有关。代谢研究表明，每日两次口服0.25微克合成1,25 - 二羟维生素D3（罗钙全）后，钙吸收可恢复正常，钙平衡得以改善。在两个中心进行的进一步研究比较了每日两次服用0.25微克罗钙全与安慰剂对骨质疏松症患者椎体骨折发生率的影响。1年后椎体骨折发生率显著降低。继续服用罗钙全第二年和第三年的患者椎体骨折发生率呈逐渐下降趋势。对于每日典型钙摄入量为700至800毫克的骨质疏松症患者，每日两次服用0.25微克的罗钙全很少引起高钙尿症或高钙血症。对每日两次服用0.25微克罗钙全治疗的患者进行为期3年的仔细肾功能测量，结果显示肾功能无恶化。这些数据表明，1,25 - 二羟维生素D3是治疗绝经后骨质疏松症患者，尤其是钙吸收不良患者的有效疗法。我们发现，它可改善钙平衡，降低椎体骨折发生率，并且只要监测膳食钙摄入量且不超过800毫克/天，使用就是安全的。
