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1.
OBJECTIVE: To compare the effects of alendronate and alfacalcidol in the prevention ofglucocorticoid-related osteoporosis in patients with a rheumatic disease. DESIGN: Randomised, double-blind, double-placebo clinical trial (www. clinicaltrials.gov; number: NCT00138983). METHODS: A total of 201 patients with rheumatic disease who were starting glucocorticoid treatment at a daily dose that was equivalent to at least 7.5 mg of prednisone were randomised to alendronate (10 mg) and a placebo capsule ofalfacalcidol daily (n = 100) or alfacalcidol (1 microg) and a placebo tablet ofalendronate daily (n = 101) for 18 months. Primary outcome was change in lumbar spine bone mineral density at 18 months. The main secondary outcome was the incidence of morphometrically confirmed vertebral deformities. RESULTS: Overall, 163 patients completed the study. The bone mineral density of the lumbar spine increased by 2.1% (95% CI: 1.1-3.1) in the alendronate group and decreased by 1.9% (95% CI: -3.I--0.7) in the alfacalcidol group. At 18 months the mean difference in change in bone mineral density between the two groups was 4.0% (95% CI: 2.4-5-5). Three patients in the alendronate group had a new vertebral deformity, compared with 8 patients in the alfacalcidol group, including 5 symptomatic vertebral fractures in 3 patients; the hazard ratio was 0.4 (95% CI: 0.1-1.4). CONCLUSION: Alendronate was more effective than alfacalcidol in preventing glucocorticoid-induced bone loss during this 18-month trial in patients with rheumatic diseases who were starting glucocorticoid treatment.  相似文献   

2.
Vitamin D deficiency is common among children and adolescents in India, in spite of abundant sunshine. We conducted a pilot; double blind randomised controlled trial to investigate the effect of vitamin D supplementation on bone mineral content in underprivileged adolescent girls, in Pune, India. Fifty post-menarcheal girls aged 14 to 15 years were randomised to receive 300,000 IU (7.5 mg) of ergocalciferol or placebo orally, 4 times/year. All participants received 250 mg elemental calcium (calcium carbonate) daily. Outcome measures included change in serum 25-hydroxyvitamin D, size adjusted bone area and bone mineral content at total body and lumbar spine. Post supplementation, the median serum concentration of 25-hydroxyvitamin D was 75.2 (64.2-85.5) nmol/L in the intervention group and 28.1 (16.7-34.0) nmol/L in the placebo group. Increment in bone outcome measures was not different in the two groups. However, there was a positive effect of intervention in the size adjusted total body bone area (p<0.05), total body bone mineral content (p<0.05) and lumbar spine bone mineral content (p<0.05), and positive trend in lumbar spine bone area (p=0.07) in girls who were within 2 years of menarche. We conclude that vitamin D supplementation did not have a beneficial effect on skeletal mineralization in girls who were more than 2 years post menarcheal. However, there was a significant positive effect of the intervention on size adjusted total body and lumbar spine bone mineral content and a positive trend in lumbar spine bone area, in girls who were <= 2 years of menarche.  相似文献   

3.
BACKGROUND: Isoflavone phytoestrogen therapy has been proposed as a natural alternative to hormone replacement therapy (HRT). HRT has a beneficial effect on bone, but few trials in humans have investigated the effects of isoflavones on bone. OBJECTIVE: The objective of the study was to determine the effect on bone density of a red clover-derived isoflavone supplement that provided a daily dose of 26 mg biochanin A, 16 mg formononetin, 1 mg genistein, and 0.5 mg daidzein for 1 y. Effects on biochemical markers of bone turnover and body composition were also studied. DESIGN: Women aged 49-65 y (n = 205) were enrolled in a double-blind, randomized, placebo-controlled trial; 177 completed the trial. Bone density, body composition, bone turnover markers, and diet were measured at baseline and after 12 mo. RESULTS: Loss of lumbar spine bone mineral content and bone mineral density was significantly (P = 0.04 and P = 0.03, respectively) lower in the women taking the isoflavone supplement than in those taking the placebo. There were no significant treatment effects on hip bone mineral content or bone mineral density, markers of bone resorption, or body composition, but bone formation markers were significantly increased (P = 0.04 and P = 0.01 for bone-specific alkaline phosphatase and N-propeptide of collagen type I, respectively) in the intervention group compared with placebo in postmenopausal women. Interactions between treatment group and menopausal status with respect to changes in other outcomes were not significant. CONCLUSION: These data suggest that, through attenuation of bone loss, isoflavones have a potentially protective effect on the lumbar spine in women.  相似文献   

4.
BACKGROUND: Adolescent mothers may be at increased risk of irreversible bone loss during pregnancy and lactation, particularly when calcium intake is low. OBJECTIVE: Longitudinal changes in bone mass from lactation to postweaning were evaluated in 10 adolescent mothers aged 15-18 y who habitually consumed <500 mg Ca/d. DESIGN: Total-body bone mineral content (TBBMC), total-body bone mineral density (TBBMD), and lumbar spine bone mineral density (LSBMD) were measured at lactation (6-24 wk postpartum) and after weaning (12-30 mo postpartum). Serum hormones (intact parathyroid hormone, estradiol, and prolactin), serum calcium, and markers of bone turnover [urinary N-telopeptide cross-linking region of type I collagen (NTx) and plasma activity of bone alkaline phosphatase] were measured at lactation. RESULTS: TBBMC, total calcium content, TBBMD, and LSBMD increased from lactation to postweaning (P < 0.01). TBBMD and LSBMD were, respectively, 3.6% and 9.7% lower than predicted at lactation and 0.3% and 4.8% lower than predicted in the postweaning period. The increase in age-matched TBBMD adequacy was correlated with the time after resumption of menses (r = 0.86, P < 0.01). Calcium accretion from lactation to postweaning correlated negatively with estradiol (r = -0.86) and prolactin (r = -0.69) and positively with intact parathyroid hormone (r = 0.72) and NTx (r = 0.84) measured at lactation (P < 0.05). CONCLUSIONS: It appears that adolescent mothers with habitually low calcium intakes recover from lactation-associated bone loss after weaning. The rate of bone accretion, however, may not be sufficient to attain peak bone mass at maturity. Hormones regulating bone turnover during lactation may influence bone recovery in adolescent mothers.  相似文献   

5.
Soymilk or progesterone for prevention of bone loss   总被引:1,自引:0,他引:1  
BACKGROUND: Given concerns over the use of hormone replacement therapy (HRT), women are seeking natural alternatives to cope with the symptoms and effects of menopause. The bone sparing effects of soy protein and its isoflavones is well established in animal studies, while 5 previous human studies on soy and bone have yielded variable outcomes due in part to their short duration of study. Progesterone has been suggested as a bone-trophic hormone, but the effect of long-term, low dose transdermal progesterone is unknown. AIM: The aim of the study was to compare for the first time the long-term effects of soymilk, with or without isoflavones with natural transdermal progesterone, or the combination, on bone mineral density in the lumbar spine and hip. METHODS: Postmenopausal, Caucasian women with established osteoporosis or at least 3 risk-factors for osteoporosis, were randomly assigned, double-blind to one of four treatment-groups: soymilk containing isoflavones (soy+, n = 23), transdermal progesterone (TPD+, n = 22), or the combination of soy+ and TDP+,(n = 22) or placebo (isoflavone-poor soymilk, soy/ and progesterone-free-cream TDP/, n = 22). All subjects received comparable intakes of calcium, minerals and vitamins. Bone mineral content (BMC) and density (BMD) were measured in lumbar spine and hip by using dual-energy X-ray absorptiometry (DEXA) at baseline and after 2 years. FINDINGS: The percentage change in lumbar spine BMD and BMC respectively, did not differ from zero in the soy+ group (+1.1%, +2.0%) and TDP+ group (/1.1%, +0.4 %) but significant bone loss occurred in the control group (/4.2%,/4.3 %) and the combined treatment group (/2.8%, /2.4 %). No significant changes occurred for femoral neck BMD or BMC. INTERPRETATION: Daily intake of two glasses of soymilk containing 76 mg isoflavones prevents lumbar spine bone loss in postmenopausal women. Transdermal progesterone had bone-sparing effects but when combined with soy milk a negative interaction between the two treatments occurs resulting in bone-loss to a greater extent than either treatment alone.  相似文献   

6.
BACKGROUND: Patients receiving home parenteral nutrition (HPN) because of intestinal failure are at high risk of developing osteoporosis. OBJECTIVE: We studied the effect of the bisphosphonate clodronate on bone mineral density (BMD) and markers of bone turnover in HPN patients. DESIGN: A 12-mo, double-blind, randomized, placebo-controlled trial was conducted to study the effect of 1500 mg clodronate, given intravenously every 3 mo for 1 y, in 20 HPN patients with a bone mass T score of the hip or lumbar spine of less than -1. The main outcome measure was the difference in the mean percentage change in the BMD of the lumbar spine measured by dual-energy X-ray absorptiometry. Secondary outcome measures included changes in the BMD of the hip, forearm, and total body and biochemical markers of bone turnover, ie, serum osteocalcin, urinary pyridinoline, and urinary deoxypyridinoline. RESULTS: The mean (+/-SEM) BMD of the lumbar spine increased by 0.8 +/- 2.0% in the clodronate group and decreased by 1.6 +/- 2.0% in the placebo group (P = 0.43). At all secondary skeletal sites (ie, hip, total body, and distal forearm), we observed no changes or small increases in the BMD of the clodronate group and decreases in the BMD of the placebo group. In the clodronate group, biochemical markers of bone resorption decreased significantly (P < 0.05). CONCLUSIONS: Clodronate significantly inhibits bone resorption as assessed by changes in biochemical markers of bone turnover. Although the mean BMD increased in the clodronate group, cyclic clodronate therapy failed to increase spinal BMD significantly at 12 mo.  相似文献   

7.
大豆异黄酮减缓绝经后妇女骨丢失的临床效应   总被引:7,自引:0,他引:7  
目的:确定大豆异黄酮减缓绝经后雌激素缺失状态下骨丢失的生理效应及其有效剂量。方法:以骨量正常或低减的绝经后妇女87人为研究对象,随机单盲分为大豆异黄酮84 mg/d和126 mg/d两个剂量组及安慰剂对照组,另以绝经后妇女10人给予7-炔诺酮2.5 mg/d作为阳性对照组,追踪24 w,测定腰椎、股骨颈和Ward,s三角区试验前后的骨密度值。结果:试验后安慰剂对照组腰椎骨密度较试验前显著下降(P<0.05), 大豆异黄酮两组及雌激素对照组各部位骨密度试验前后无显著变化 (P>0.05);协方差分析表明,试验后大豆异黄酮126 mg/d组、和雌激素对照组腰椎部位骨密度均值及其变化率显著高于安慰剂组(P<0.05),回归分析表明大豆异黄酮对各部位的骨密度变化率均有显著的正向作用(P<0.05)。结论:大豆异黄酮84~126 mg/d可减缓绝经后妇女骨的丢失,维持骨密度的相对稳定,其显效剂量是126 mg/d。  相似文献   

8.
目的探讨绝经后女性血清脂联素(Adiponectin)与骨转换生化指标的关系。方法用酶联免疫吸附试验测定287名40~80岁健康绝经后女性血清脂联素以及血清骨特异性碱性磷酸酶(Bone alkaline phosphatase,BAP)和Ⅰ型胶原交联氨基末端肽(cross-linked N-telopeptide of type I collagen,NTx);用双能X线骨密度扫描仪(dual energy X-ray absorptiometry,DEXA)测定总体、腰椎正位、总髋部骨、左前臂骨密度(bone mineral density,BMD)以及体脂、瘦体质量;分析它们之间的关系。结果BAP与总体骨密度、腰椎BMD、髋部总体BMD、前臂BMD均呈负相关(r=-0.210、-0.236、-0.223、-0.226,P0.05),校正年龄和体质指数后,相关性都依然存在(r=-0.168、-0.187、-0.169、-0.175,P0.05)。NTx与总体BMD、腰椎BMD、髋部总体BMD、前臂BMD均呈负相关(r=-0.238、-0.232、-0.239、-0.221,P0.05),校正年龄和体质指数后,相关性都依然存在(r=-0.201、-0.189、-0.193、-0.185,P0.05)。脂联素与BAP、NTx均呈正相关(r=0.202、0.215,P0.05),校正年龄和体脂后,相关性都依然存在(r=0.169、0.183,P0.05)。脂联素与BAP以二次方程模型拟合程度最好,其最大决定系数(R2)为0.055;脂联素与NTx以二次方程模型拟合程度最好,其最大决定系数(R2)为0.089。绝经后骨质疏松(postmenopausal osteoporosis,PMO)女性血清脂联素水平较年龄相匹配的正常对照组增高(P0.05)。结论血清脂联素水平与骨转换生化指标呈正相关,提示脂联素可能为新型骨转换预测因子。  相似文献   

9.
The longevity of recipients of liver transplant may be compromised by spinal osteoporosis and vertebral fractures. However, femoral neck fractures are associated with a higher morbidity and mortality than spine fractures. As there is little information on bone loss at this clinically important site of fracture, the aim of this study was to determine whether accelerated bone loss occurs at the proximal femur following transplantation. Bone mineral density and body composition were measured at the femoral neck, lumbar spine and total body, using dual x-ray absorptiometry in 22 men and 19 women, age 46 +/- 1.4 y (mean +/- SEM) before and at a mean of 19 mo after surgery (range 3-44). Results were expressed in absolute terms (g/cm2) and as a z score. Before transplantation, z scores for bone mineral density were reduced at the femoral neck (-0.47 +/- 0.21 SD), trochanter (-0.56 +/- 0.19 SD), Ward's triangle (-0.35 +/- 0.14 SD), lumbar spine (-0.76 +/- 0.13 SD), and total body (-0.78 +/- 0.15 SD) (all P < 0.01 to < 0.001). Following transplantation, bone mineral density decreased by 8.0 +/- 1.7% at the femoral neck (P < or = 0.01) and by 2.0 +/- 1.2% at the lumbar spine (P < or = 0.05). Total weight increased by 12.2 +/- 2.3%, lean mass decreased by 5.7 +/- 1.4%, while fat mass increased from 24.1 +/- 2.0% to 35.1 +/- 1.8% (all P < or = 0.001). Patients with end-stage liver disease have reduced bone mineral density. Liver transplantation is associated with a rapid decrease in bone mineral density at the proximal femur, further increasing fracture risk and a reduction in lean (muscle) mass, which may also predispose to falls. Prophylactic therapy to prevent further bone loss should be considered in patients after liver transplantation.  相似文献   

10.
目的了解中小学教师骨质疏松症的患病率和影响因素,为针对性采取预防措施提供参考。方法检测1075例武汉市江岸区中小学教师的骨密度,采用SPSS 16.0软件包进行统计分析。结果男性中小学教师身高、体重、BMI均明显高于女性(P<0.05);40~49年龄组与50岁及以上年龄组男女中小学教师脚跟骨、腰椎总骨密度均明显低于29岁及以下年龄组(P<0.05),50岁及以上年龄组男女中小学教师脚跟骨、腰椎总骨密度明显低于30~39年龄组(P<0.05);随着男女中小学教师年龄逐渐增长,骨量流失和骨质疏松症发生率明显升高(P<0.05),且女性中小学教师骨量流失和骨质疏松症发生率明显高于男性中小学教师(P<0.05);经多因素Logistic回归分析发现,年龄为脚跟骨、腰椎总骨密度的负相关因素,身高、体重、BMI为脚跟骨、腰椎总骨密度的正相关因素。结论随着年龄增长,中小学教师脚跟骨、腰椎总骨密度明显下降,骨量流失和骨质疏松症发生率明显升高,且女性表现尤为明显,建议采取适宜运动锻炼和合理饮食配伍等多方面综合措施,早期防治骨质疏松症的发生。  相似文献   

11.
In earlier observational work, the dietary calcium:protein ratio was directly related to bone accrual in healthy postadolescent women. In this study, we sought to test the hypothesis that augmented calcium intake would increase postadolescent skeletal consolidation, using a double-blind, randomized, placebo-controlled design. We recruited 152 healthy young women (age 23.1 +/- 2.7 y, BMI 22.5 +/- 3.0 kg/m2); their usual diets, as assessed by 7-d food diaries, were low in calcium (605 +/- 181 mg/d; 15.1 +/- 4.5 mmol/d) and in the calcium:protein ratio (10.1 +/- 2.0 mg/g). The subjects were randomly assigned to supplemental calcium [500 mg calcium (12.5 mmol) as the carbonate, 3 times/d, with meals] or placebo capsules identical in appearance; all participants also took a daily multivitamin, and they were followed for up to 36 mo with bone densitometry (dual energy X-ray absorptiometry; DXA) at 6-mo intervals. A total of 121 subjects remained in the study for at least 12 mo (median time in the study, 35 mo), with a mean compliance level (observed/expected tablet consumption) of 87.7%. DXA data for these 121 subjects indicated modest but significant mean rates of increase (i.e., 0.24 to 1.10%/y) in bone mineral content (BMC; total body, total hip, and lumbar spine) and in lumbar spine bone mineral density (BMD) but no change in total hip BMD. None of these rates of change differed by group, i.e., calcium supplementation did not have any measurable effect on bone mass accrual. By midstudy, the calcium content of the subjects' usual diets for both groups had risen by approximately 15%. The combined effect of improved intakes of dietary calcium and the small amount of calcium added by the multivitamin tablets resulted in a mean calcium intake for the control group > 800 mg (20 mmol)/d, possibly at or near the threshold beyond which additional calcium has no further effect on bone accrual.  相似文献   

12.
Introduction  Milk is a good source of bioavailable calcium compared with other foods. Recent in vitro and in vivo studies have shown that milk whey protein, especially its basic protein fraction (milk basic protein, MBP), contains several components capable of promoting bone formation and inhibiting bone resorption. The objective of this study was to examine the effects of MBP on bone mineral density (BMD) and bone metabolism of healthy young women. Methods  Eighty-four healthy young women were randomly assigned to three groups: control group, whole milk group or MBP group treated with milk containing 40 mg MBP for 8 months. The bone mineral density of total body, the lumbar vertebrae L2–L4 and the left forearm of each subject were measured by dual-energy X-ray absorptiometry (DEXA) at 0 and 8 months of treatment. Serum indexes of bone metabolism were measured at 0, 3, 6 and 8 months. Eighty-one subjects who completed the study in accordance with the protocol were included in the analysis. Results  Total BMD in all groups significantly increased compared with baseline values. However, no significant difference on the mean rate of gain of total BMD was observed among the MBP group (2.19%), the whole milk group (2.63%) and the control group (1.61%). Serum cross-linked N-teleopeptides of type-I collagen (NTx) in MBP group at 8 months and in whole milk group at 6 months were significantly decreased from baseline. There were no significant differences between whole milk group and MBP group; however, after combining the milk groups, NTx had significantly decreased from baseline. No significant increase was observed in serum bone-specific alkaline phosphatase (BAP) in both whole milk group and MBP group. Conclusion  No significant effect of MBP on bone mineral density and bone metabolism was observed, but milk supplementation was effective in suppressing bone resorption.  相似文献   

13.
The bone density in the spine, femoral neck and radius in 31 outpatients with anorexia nervosa (AN) was measured by photon absorptiometry and compared with 31 age matched controls. In all bone sites measured the patients with anorexia nervosa had reduced bone mineral density (spine- control 0.91 + .10 gHA/cm2, AN 0.75 + .09 gHA/cm2; femur- control 0.87 + .09 gHA/cm2, AN 0.67 + .07 gHA/cm2; radius-control 0.41 + .04 gHA/cm2, AN 0.38 + 0.9 gHA/cm2). The mean difference between the groups was greatest in the femoral neck at 0.21 gHA/cm2 (95% CI 0.18-.024 p less than 0.001) and least at the radius 0.04 gHA/cm2 (95% CI 0.02-0.06, p less than 0.05), the lumbar spine was intermediate with a mean difference of 0.16 gHA/cm2 (95% CI 0.12-0.2 p less than 0.001). Femoral and spinal bone mineral density was positively correlated with body mass and negatively correlated with duration of amenorrhoea. Three of these patients had vertebral crush fractures which suggests that this diminution in bone density is of clinical significance.  相似文献   

14.
In piglets, feeding arachidonic acid (AA) and docosahexaenoic acid (DHA) in a 5:1 ratio leads to elevated bone mass, but the optimal total quantity requires clarification. We studied bone mass and modeling of piglets that were randomized to receive 1 of 4 formulas for 15 d: control formula or the same formula with various levels of AA:DHA (0.5:0.1 g, 1.0:0.2 g or 2.0:0.4 g AA:DHA/100 g of fat). Measurements included: bone area (BA), mineral content (BMC), and density (BMD) of whole body, lumbar spine, and excised femurs; biomarkers of bone modeling were plasma osteocalcin and urinary cross-linked N-telopeptides of type 1 collagen (NTx), tibial ex vivo release of prostaglandin E(2) (PGE(2)), plasma insulin-like growth factor-1 (IGF-1), and tissue fatty acids. Main effects were identified using ANOVA and post hoc Bonferroni t tests. In supplemented piglets, relations among liver fatty acid proportions and bone mass were assessed using Pearson correlations. Whole body (P = 0.028) and lumbar spine (P = 0.043) BMD were higher in the group supplemented with 0.5:0.1 g AA:DHA/100 g of fat than in controls. Tissue AA and DHA increased in proportion to diet levels. Liver eicosapentaenoic acid (EPA) correlated positively (r > or = 0.38, P < or = 0.05) with whole body and femur BMC and BMD and lumbar spine BMC. Liver AA:EPA ratio correlated negatively (r > or = -0.039, P < or = 0.05) with whole body, femur, and lumbar spine BMC plus whole body and femur BMD. Dietary 1.0:0.2 g AA:DHA/100 g reduced NTx relative to 2.0:0.4 g AA:DHA/100 g of fat (P = 0.039). The diets did not affect the other biochemical variables measured. Low levels of dietary AA:DHA (0.5:0.1 g/100 g of fat) elevate bone mass, but higher amounts are not beneficial.  相似文献   

15.
BACKGROUND: No published studies have directly examined the effect of soy protein with isoflavones on bone or bone turnover in perimenopausal women. OBJECTIVE: Our objective was to determine the effects of 24 wk of consumption of soy protein isolate with isoflavones (80.4 mg/d) in attenuating bone loss during the menopausal transition. DESIGN: Perimenopausal subjects were randomly assigned, double blind, to treatment: isoflavone-rich soy (SPI+; n = 24), isoflavone-poor soy (SPI-; n = 24), or whey (control; n = 21) protein. At baseline and posttreatment, lumbar spine bone mineral density (BMD) and bone mineral content (BMC) were measured by using dual-energy X-ray absorptiometry. At baseline, midtreatment, and posttreatment, urinary N:-telopeptides and serum bone-specific alkaline phosphatase (BAP) were measured. RESULTS: The percentage change in lumbar spine BMD and BMC, respectively, did not differ from zero in the SPI+ or SPI- groups, but loss occurred in the control group (-1.28%, P: = 0.0041; -1.73%, P: = 0.0037). By regression analysis, SPI+ treatment had a positive effect on change in BMD (5.6%; P: = 0.023) and BMC (10.1%; P: = 0.0032). Baseline BMD and BMC (P: < or = 0.0001) negatively affected the percentage change in their respective models; baseline body weight (P: = 0.0036) and bone-free lean weight (P: = 0.016) contributed positively to percentage change in BMD and BMC, respectively. Serum BAP posttreatment was negatively related to percentage change in BMD (P: = 0.0016) and BMC (P: = 0.019). Contrast coding using analyses of covariance with BMD or BMC as the outcome showed that isoflavones, not soy protein, exerted the effect. CONCLUSION: Soy isoflavones attenuated bone loss from the lumbar spine in perimenopausal women.  相似文献   

16.
目的观察唑来膦酸对妇科恶性肿瘤术后骨质疏松患者的疗效并进行不良反应监测与分析。方法选择2010年2月至2014年2月辽河油田总医院与海原县中医医院收治的120例妇科恶性肿瘤术后骨质疏松患者,采用随机双盲对照的研究设计将患者分为观察组与对照组,各60例。观察组予5mg唑来膦酸并服用钙尔奇D片,对照组给予5mg安慰剂并服用钙尔奇D片,比较两组治疗前后视觉模拟评分法(visual analogue scale/score,VAS)评分、腰椎与股骨颈骨密度以及急性期不良反应等情况。结果观察组VAS评分、腰椎与股骨颈骨密度均有显著改善(P0.05),且效果明显优于对照组(P0.05);观察组急性期不良反应发生率高达31.79%,但症状较轻且能较快缓解,并无严重不良反应。结论唑来膦酸对妇科恶性肿瘤术后骨质疏松的患者疗效明显,具有一定的安全性。  相似文献   

17.
BACKGROUND: High calcium intakes during adolescence may increase bone acquisition. The magnitude of the effect of dietary calcium supplementation and the timing of its administration to achieve significant effects on bone health are still incompletely defined. OBJECTIVE: The objective of this study was to assess the effect of calcium supplementation on bone mass accretion in postmenarcheal adolescent girls with low calcium intakes. DESIGN: A double-blind, placebo-controlled calcium supplementation study was implemented. One hundred girls with a mean (+/- SD) age of 14 +/- 0.5 y with habitual calcium intakes < 800 mg/d completed a 12-mo protocol. The treatment group received a daily supplement containing 1000 mg elemental calcium. Bone mineral density (BMD) and bone mineral content (BMC) of the total body, lumbar spine, and femoral neck were determined at inclusion, 6 mo, and 12 mo. Also measured were serum concentrations of biochemical markers of bone turnover (osteocalcin and deoxypyridinoline), parathyroid hormone, and vitamin D. RESULTS: The calcium-supplemented group had greater accretion of total-body BMD and lumbar spine BMD but not BMC than did the control group. Calcium supplementation appeared selectively beneficial for girls who were 2 y postmenarcheal. Calcium supplementation significantly decreased bone turnover and decreased serum parathyroid hormone concentrations. CONCLUSION: Calcium supplementation of postmenarcheal girls with low calcium intakes enhances bone mineral acquisition, especially in girls > 2 y past the onset of menarche.  相似文献   

18.
INTRODUCTION: This 7-year, prospective, matched-cohort, clinical study evaluated the effects of intramuscular depot medroxyprogesterone acetate (DMPA) (150 mg/mL) on bone mineral density (BMD) in women aged 25-35 years. METHODS: Bone mineral density changes in new DMPA-IM users (n=248) were compared with those in women using nonhormonal contraception (n=360) for up to 240 weeks of treatment and 96 weeks of posttreatment follow-up (in subjects receiving >or=1 dose). RESULTS: At week 240 of treatment, mean percentage changes from baseline in DMPA-IM vs. nonhormonal subjects were: -5.16% (n=21) vs. +0.19% (n=65), total hip (p<.001); -5.38% (n=33) vs. +0.43% (n=105), lumbar spine (p<.001). At week 96 posttreatment, these values were: -0.20% (n=25) vs. +0.84% (n=43), total hip (p=.047); -1.19% (n=41) vs. +0.47% (n=66), lumbar spine (p=.017). CONCLUSIONS: These results show BMD declines during DMPA-IM use; following discontinuation, significant increases in BMD occur through 96 weeks posttreatment.  相似文献   

19.
目的探讨绝经后女性血清脂肪因子瘦素(Leptin)、抵抗素(Resistin)、内脂素(Visfatin)及Apelin与骨转换生化指标的关系。方法酶联免疫吸附试验测定287名40~80岁健康绝经后女性血清Leptin、Resistin、Visfatin和Ape-lin,以及血清骨特异性碱性磷酸酶(Bonealk aline phosphatase,BAP)和Ⅰ型胶原交联氨基末端肽(cross-linked N-telopep-tide of type I collagen,NTx);用双能X线骨密度扫描仪(dual energy X-ray absorptiometry,DEXA)测定总体、腰椎正位、左前臂、总髋部骨密度(bone mineral density,BMD)以及体脂、瘦体质量;以方差分析、直线相关(Pearson)分析它们之间的关系。结果BAP与总体BMD、腰椎BMD、髋部总体BMD、前臂BMD均呈负相关(r=-0.210、-0.236、-0.223、-0.226,P0.05),校正年龄和BMI后,相关性都依然存在(r=-0.168、-0.187、-0.169、-0.175,P0.05)。NTx与总体BMD、腰椎BMD、髋部总体BMD、前臂BMD均呈负相关(r=-0.238、-0.232、-0.239、-0.221,P0.05),校正年龄和BMI后,相关性依然存在(r=-0.201、-0.189、-0.193、-0.185,P0.05)。Leptin、Resistin、Visfatin、Aplein与BAP、NTx相关差异均无统计学意义。绝经后骨质疏松女性与健康对照组间血清Leptin、Resistin、Visfatin、Apelin水平差异无统计学意义(P0.05)。结论Leptin、Resistin、Visfatin及Apelin不是骨代谢的关键调控因子。  相似文献   

20.
BACKGROUND: Information concerning the adequacy of bone mineralization in children who customarily avoid drinking cow milk is sparse. OBJECTIVE: The objective was to evaluate dietary calcium intakes, anthropometric measures, and bone health in prepubertal children with a history of long-term milk avoidance. DESIGN: We recruited 50 milk avoiders (30 girls, 20 boys) aged 3-10 y by advertisement. We measured current dietary calcium intakes with a food-frequency questionnaire and body composition and bone mineral density with dual-energy X-ray absorptiometry and compared the results with those of 200 milk-drinking control children. RESULTS: The reasons for milk avoidance were intolerance (40%), bad taste (42%), and lifestyle choice (18%). Dietary calcium intakes were low (443 +/- 230 mg Ca/d), and few children consumed substitute calcium-rich drinks or mineral supplements. Although 9 children (18%) were obese, the milk avoiders were shorter (P < 0.01), had smaller skeletons (P < 0.01), had a lower total-body bone mineral content (P < 0.01), and had lower z scores (P < 0.05) for areal bone mineral density at the femoral neck, hip trochanter, lumbar spine, ultradistal radius, and 33% radius than did control children of the same age and sex from the same community. The z scores for volumetric (size-adjusted) bone mineral density (g/cm(3)) were -0.72 +/- 1.17 for the lumbar spine and -0.72 +/- 1.35 for the 33% radius (P < 0.001). Twelve children (24%) had previously broken bones. CONCLUSIONS: In growing children, long-term avoidance of cow milk is associated with small stature and poor bone health. This is a major concern that warrants further study.  相似文献   

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