Differences in mineral homeostasis, volumetric bone mass and femoral neck axis length in black and white South African women
Differences in mineral homeostasis, volumetric bone mass and femoral neck axis length in black and white South African women
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DOI：
10.1007/bf01623684
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发表时间：
1997-01-01
影响因子：
4
通讯作者：
Zachen, D
中科院分区：
文献类型：
--
作者：
Daniels, ED;Pettifor, JM;Zachen, D
在南非，黑人和白色女性的脊椎骨和腰椎骨矿物质密度（BMD）相似。然而，已发现黑人女性的股骨BMD高于白色女性。采用两种不同的技术重新计算BMD，以消除身高种族差异对区域BMD测量的可能混杂影响，计算体积骨矿物质表观密度（BMAD）值，并根据身体和骨骼大小校正骨矿物质含量（BMC）。本报告分析了一组20至49岁绝经前（105名白人和74名黑人）和45至64岁绝经后（50名白人和65名黑人）的南非女性护士的BMD（身高和体重校正），BMAD，BMC（身体和骨骼尺寸校正），股骨颈轴长度（FNAL），矿物质稳态和骨转换（BT）的差异。校正后的BMD和BMC结果是一致的，表明绝经前和绝经后的黑人和白人具有相似的桡骨远端和腰椎骨量，但白人的股骨颈骨量低于黑人。相反，BMAD研究结果表明，绝经前后的白人腰椎和股骨颈骨量低于黑人，但桡骨远端骨量与黑人相似。绝经后白人的骨密度下降率高于黑人。绝经前白人股骨颈BMD比黑人低12.1%，绝经后白人股骨颈BMD比黑人低16.5%。绝经前黑人股骨颈BMD与体重呈正相关（R-2 = 0.5，p = 0.0001），而白人则无相关性。在绝经前和绝经后组中，黑人的FNAL都比白人短。与白人相比，黑人的血清25-羟维生素D（25-（OH）D）水平较低，1，25-二羟维生素D（1，25-（OH）（2）D）水平较高。有骨形成（血清碱性磷酸酶和骨钙素）或骨吸收（尿羟脯氨酸和吡啶啉），或在饮食中的钙摄入量在绝经前或绝经后组的生化标志物没有种族差异。在绝经后组中，与黑人相比，白人的离子血清钙较高（p = 0.003），血清白蛋白相似，血清甲状旁腺激素较低（p = 0.003），尿钙排泄较高（p = 0.0001）。这些结果表明，较高的峰值股骨颈骨密度在南非黑人比白人可能是由更大的负重黑人和显着较低的股骨颈骨密度在绝经后的白人比黑人是由较低的峰值股骨颈骨密度和更快的绝经后下降的BMD在白人。南非白人股骨颈骨折的发生率高于黑人，这可能是由于白人股骨颈BMD较低和FNAL较长。绝经后白人BMD下降的速度高于黑人，这与白人尿钙排泄增加有关。BT的生化标志物的测量并没有帮助我们理解受试者的BMD和骨骼代谢的种族差异。
In South Africa, appendicular and lumbar spine bone mineral density (BMD) have been found to be similar in black and white women. However, femoral BMD has been found to be higher in black than in white women. Two different techniques were used to recalculate BMD to eliminate the possible confounding influence of ethnic differences in height on areal BMD measurements, Volumetric bone mineral apparent density (BMAD) values were calculated and bone mineral content (BMC) was corrected for body and bone size. This report analyses differences in BMD (corrected for height and weight), BMAD, BMC (corrected for body and bone size), femoral neck axis length (FNAL), mineral homeostasis and bone turnover (BT) in a group of 20 to 49-year-old premenopausal (105 whites and 74 blacks) and 45 to 64-year-old postmenopausal (50 whites and 65 blacks) female South African nurses. The corrected BMD and BMC findings were congruous, showing that both pre- and postmenopausal blacks and whites have similar distal radius and lumbar spine bone mass but that whites have lower femoral neck bone mass than blacks. In contrast, BMAD findings suggest that pre- and postmenopausal whites have lower bone mass at the lumbar spine and femoral neck than blacks but similar bone mass at the distal radius to blacks. There is a greater rate of decline in BMD in postmenopausal whites than in blacks. BMD at the femoral neck was 12.1% lower in premenopausal whites and 16.5% lower in postmenopausal whites than in blacks. There was a positive association between femoral neck BMD and weight in premenopausal blacks (R-2 = 0.5, p = 0.0001) but not in whites. Blacks had shorter FNAL than whites in both the pre- and postmenopausal groups. Blacks had lower serum 25-hydroxyvitamin D (25-(OH)D) and higher 1,25-dihydroxyvitamin D (1,25-(OH)(2)D) levels than whites. There were no ethnic differences in biochemical markers of bone formation (serum alkaline phosphatase and osteocalcin) or bone resorption (urine hydroxyproline and pyridinoline), or in dietary calcium intake in either the pre- or postmenopausal groups. In the postmenopausal group, whites had higher ionized serum calcium (p = 0.003), similar serum albumin, lower serum parathyroid hormone (p = 0.003) and higher urinary calcium excretion (p = 0.0001) than blacks. These results suggest that the higher peak femoral neck BMD in South African blacks than in whites might be determined by greater weightbearing in blacks and that the significantly lower femoral neck BMD in postmenopausal whites than in blacks is determined by lower peak femoral neck BMD and a faster postmenopausal decline in BMD in whites. The higher incidence of femoral neck fractures in South African whites than in blacks is probably determined by the lower femoral neck BMD and longer FNAL in whites, The greater rate of decline in BMD in postmenopausal whites than in blacks is associated with an increase in urinary calcium excretion in whites. Measurement of biochemical markers of BT has not contributed to the understanding of ethnic differences in BMD and skeletal metabolism in our subjects.