Recker R R, Hinders S, Davies K M, Heaney R P, Stegman M R, Lappe J M, Kimmel D B
Department of Medicine, Creighton University, School of Medicine, Omaha, Nebraska, USA.
J Bone Miner Res. 1996 Dec;11(12):1961-6. doi: 10.1002/jbmr.5650111218.
We tested the spine antifracture and bone sparing efficacy of 1.2 g/day of oral calcium as carbonate in two groups of elderly women, one with prevalent fractures (PF, n = 94) on entry and the other without (NPF, n = 103). It was a prospective randomized, double-blind, placebo-controlled trial in mostly rural communities in women over age 60 who were living independently and were consuming < 1 g/day of calcium. We obtained annual lateral spine radiographs and semiannual forearm bone density over 4.3 +/- 1.1 years and determined vertebral fractures by radiographic morphometry augmented by physician assessment. In the PF group, 15 of 53 subjects on calcium had incident fractures, compared with 21 of 41 on placebo (p = 0.023, chi2). Calcium did not reduce the rate of incident fractures in the NPF group. Those with a prevalent fracture on entry and not treated with calcium were 2.8 times more likely to experience an incident fracture than all others. Change in the forearm bone mass on placebo in the PF group was -1.24 +/- 2.41%/year compared with +0.31 +/- 1.80%/year on calcium (p < 0.001). In the NPF group, the difference was less: -0.39 +/- 2.08%/year versus 0.00 +/- 1.64%/year (p = 0.2). We conclude that in elderly postmenopausal women with spine fractures and selfselected calcium intakes of < 1 g/day, a calcium supplement of 1.2 g/day reduces the incidence of spine fractures and halts measurable bone loss.
我们在两组老年女性中测试了每日口服1.2克碳酸钙的脊柱抗骨折和保骨功效，一组入组时已有骨折史（PF组，n = 94），另一组无骨折史（NPF组，n = 103）。这是一项前瞻性随机双盲安慰剂对照试验，研究对象主要是60岁以上、独立生活且每日钙摄入量低于1克的农村社区女性。在4.3±1.1年的时间里，我们每年获取脊柱侧位X光片，每半年测量一次前臂骨密度，并通过影像学形态测量法结合医生评估来确定椎体骨折情况。在PF组中，服用钙剂的53名受试者中有15人发生新发骨折，而服用安慰剂的41名受试者中有21人发生新发骨折（p = 0.023，卡方检验）。钙剂并未降低NPF组的新发骨折率。入组时已有骨折史且未接受钙剂治疗的患者发生新发骨折的可能性是其他所有患者的2.8倍。PF组中，安慰剂组前臂骨量的年变化率为-1.24±2.41%，而钙剂组为+0.31±1.80%（p < 0.001）。在NPF组中，差异较小：分别为-0.39±2.08%/年和0.00±1.64%/年（p = 0.2）。我们得出结论，对于有脊柱骨折且自行选择每日钙摄入量低于1克的绝经后老年女性，每日补充1.2克钙剂可降低脊柱骨折的发生率并阻止可测量的骨质流失。
