Alfacalcidol reduces accelerated bone turnover in elderly women with osteoporosis

To evaluate the effects of alfacalcidol on bone turnover in elderly women with osteoporosis, an open-label, prospective, calcium-controlled study was conducted. A total of 80 patients with osteoporosis were divided into two groups: the control group, group C (mean age, 78.0 years), in which patients were given calcium, and group D (mean age, 77.4 years), in which the patients were given alfacalcidol 1µg/day together with calcium for 6 months. Calcium regulation, lumbar bone mineral density (LBMD), and markers for bone turnover were assessed. A significant increase in urinary calcium/creatinine ratio (90% increase from baseline at 3 months; P = 0.0083, and 60% at 6 months; P = 0.0091) and a significant decrease in serum parathyroid hormone (30% decrease from baseline at 6 months; P < 0.0001) was observed in group D compared with the corresponding changes in group C. Significant decreases of bone resorption markers (deoxypyridinoline and N-telopeptide) at 6 months (about 15% decrease from the baseline values) were observed in group D compared with the corresponding changes in group C. The changes in bone formation markers (bone-derived alkaline phosphatase and osteocalcin) in group D were significantly different at 6 months (–21.5%; P = 0.0047 and –13.4%; P = 0.0032, respectively) from the values in group C. The magnitudes of the decrease in bone turnover markers were highly correlated with the corresponding baseline values, suggesting that alfacalcidol treatment effectively reduces bone turnover in patients with high bone turnover rates. The LBMD in group D increased by 1.7% and that in group C decreased by 1.6% (P = 0.0384). The changes in calcium metabolism and LBMD were in good agreement with those in previous reports. Although the changes in bone turnover markers in group D were slight, significant reduction in bone turnover with alfacalcidol treatment, together with the change in calcium metabolism, may account for the effects of alfacalcidol on BMD and on fracture prevention reported previously. In conclusion, alfacalcidol reduces bone turnover in elderly women with high-bone-turnover osteoporosis, and it may have beneficial effects on bone.     

尼尔雌醇防治绝经后及老年妇女骨质疏松的临床观察

对 2 0例绝经后妇女和老年妇女分别给予尼尔雌醇用药 3个月 ,并于给药前后分别测定空腹尿钙与肌酐 (Ca/Cr) ,羟脯氨酸与肌酐 (OHPr/Cr)比值以及血清碱性磷酸酶 (AKP)、雌二醇 (E2 )、降钙素 (CT)的值。以探讨尼尔雌醇减缓不同绝经年限妇女骨量丢失的作用机制。结果显示尼尔雌醇给药前后两组妇女血清E2 的水平未见明显变化 ,但其血清CT的水平均较给药前有程度不同的升高。空腹尿Ca/Cr、OHPr/Cr比值以及血清AKP水平均较给药前显著下降 (P <0 0 0 5及P <0 0 1)。故此提示 ,尼尔雌醇可能通过刺激甲状腺C细胞而增加CT的分泌或直接作用于骨组织等多种途径抑制骨质的吸收 ,维持其骨矿含量的相对稳定。因此 ,本研究在国内首次为尼尔雌醇用于减缓老年妇女骨质的丢失提供了一定的理论依据。     

新疆老年男性骨转化生化标志物及性激素与骨质疏松症的相关性研究

目的探讨新疆老年男性骨转换生化标志物及性激素水平与原发性骨质疏松症的关系。方法采用双能X线骨密度仪检测146例老年男性患者腰椎、左侧股骨骨密度(BMD),平均年龄:72.4±7.9岁,基于骨密度T值分为骨量正常组(75例)和骨量异常组(71例),采用酶联免疫法测定Ⅰ型前胶原氨基端原肽(PINP)和Ⅰ型胶原C末端肽(CTX),放射免疫法测定雌二醇(E2)和睾酮(T),比较两组骨转换生化指标和性激素水平是否存在差异及其与骨密度的相关性。结果 1 PINP与CTX在骨量正常组和骨量异常组差异均无统计学意义(P0.05);两者偏相关分析呈显著正相关(r=0.746 P=0.000)。2雌二醇、睾酮在两组中比较,差异有统计学意义(P0.05)。骨量异常组雌二醇(17.48±7.61)低于骨量正常组(21.31±11.43),t=2.391,P=0.018;骨量异常组睾酮(3.50±1.02)低于骨量正常组(3.98±1.43),t=2.331,P=0.021。3汉族人群左侧髋关节骨密度高于维吾尔族人群,除Inter Tro部位外,差异均有统计学意义(P0.05);年龄与髋关节各部位骨密度呈显著负相关。结论性激素水平降低可能是影响男性骨量减少的一个重要危险因素,而雌激素可能占主要地位;随着年龄的增加,老年男性髋关节骨密度呈下降趋势,测定左侧髋关节骨密度对诊断骨质疏松症有着重要意义。     

Impairment of bone turnover in elderly women with hip fracture

Summary Hip fracture is one of the most severe consequences of osteoporosis affecting aged women. However, abnormalities of bone turnover responsible for bone loss in this condition have not been clearly defined. To further evaluate the bone metabolic status of women sustaining hip fracture, we have prospectively measured serum osteocalcin as a marker of bone formation and urinary excretion of pyridinoline (Pyr) and deoxypyridinoline (D-pyr) cross-links as markers of bone collagen degradation in 174 independently living women (80 ± 8 years) within a few hours after a hip fracture. Comparison was made with 77 age-matched controls (80 ± 5 years) and 17 premenopausal women (39 ± 3 years). In addition 15 of the patients were followed with daily measurements during the first postoperative week. At the time of admission osteocalcin was 20% lower in the fractured women compared to the elderly controls (7.6 ± 3.8 vs. 9.5 ± 4.5 nglml,P = 0.001). Pyr and D-pyr were 36% and 40% higher, respectively (P = 0.0001), than in elderly controls and 85% and 76% higher than in premenopausal controls (P = 0.0001). Serum osteocalcin did not correlate with the cortisol level measured at the same time (r = 0.03, ns), nor with serum albumin and creatinine. Serum osteocalcin remained unchanged within 18 hours after fracture, whereafter it progressively decreased until the third postoperative day. No correlation was noted between the excretion of pyridinoline cross-links and the time elapsed from fracture.These data suggest that the abnormal levels of osteocalcin and pyridinolines are unrelated to traumatically induced acute changes, but reflect abnormalities of bone turnover existing prior to the fracture. Thus, hip-fracture patients have biochemical evidence of decreased bone formation and increased bone resorption when compared to age-matched controls. We suggest that these abnormalities may play a role in the decrease of the bone mass and the consequently increased bone fragility that characterize the osteoporotic hip fracture in the elderly.     

Role of biochemical markers of bone turnover as prognostic indicator of successful osteoporosis therapy

Most of the currently available anti-osteoporosis medications promptly and significantly influence the rate of bone turnover. Biochemical markers of bone turnover now provide a high sensitivity to change, allowing the detection of these bone turnover changes within a couple of weeks. Since the anti-fracture efficacy of inhibitors of bone resorption or stimulators of bone formation appears to be largely independent of baseline bone turnover, biochemical markers do not appear to play a significant role in the selection of one particular drug, for an individual patient. However, there are consistent data showing that short-term changes in biochemical markers of bone turnover may be significant predictors of future changes in bone mineral density or fracture reduction, hence suggesting that bone turnover markers play a significant role in the monitoring of anti-osteoporosis therapy.     

Effects of high-impact exercise on bone mineral density: a randomized controlled trial in premenopausal women

Introduction: The purpose of this randomized controlled study was to assess the effects of high-impact exercise on the bone mineral density (BMD) of premenopausal women at the population level. Materials and methods: The study population consisted of a random population-based sample of 120 women from a cohort of 5,161 women, aged 35 to 40 years. They were randomly assigned to either an exercise or control group. The exercise regimen consisted of supervised, progressive high-impact exercises three times per week and an additional home program for 12 months. BMD was measured on the lumbar spine (L1–L4), proximal femur, and distal forearm, by dual-energy X-ray absorptiometry at baseline and after 12 months. Calcaneal bone was measured using quantitative ultrasound. Results: Thirty-nine women (65%) in the exercise group and 41 women (68%) in the control group completed the study. The exercise group demonstrated significant change compared with the control group in femoral neck BMD (1.1% vs –0.4%; p=0.003), intertrochanteric BMD (0.8% vs –0.2%; p=0.029), and total femoral BMD (0.1% vs –0.3%; p=0.006). No exercise-induced effects were found in the total lumbar BMD or in the lumbar vertebrae L2–L4. Instead, L1 BMD (2.2% vs –0.4%; p=0.002) increased significantly more in the exercise group than in the control group. Calcaneal broadband ultrasound attenuation showed also a significant change in the exercise group compared with the control group (7.3% vs –0.6%; p=0.015). The changes were also significant within the exercise group, but not within the control group. There were no significant differences between or within the groups in the distal forearm. Conclusions: This study indicates that high-impact exercise is effective in improving bone mineral density in the lumbar spine and upper femur in premenopausal women, and the results of the study may be generalized at the population level. This type of training may be an efficient, safe, and inexpensive way to prevent osteoporosis later in life.     

阿伦磷酸钠对绝经后2型糖尿病合并骨质疏松症患者骨代谢的影响

目的 探讨阿伦膦酸钠对绝经后2型糖尿病合并骨质疏松症患者骨代谢及骨密度的影响。方法 选择2012年1月至2013年1月在本院接受治疗的绝经后2型糖尿病合并骨质疏松症患者51例,给予阿伦膦酸钠治疗6个月。采用美国Norland双光能X线骨密度检测仪对所有患者进行腰椎L2-L4和左侧股骨近端（包括Neck、Troch、Ward三角区)骨密度测量,并测定身高、体重、空腹血糖(FBG)、HbAlc、PTH、OC、CTX、25（OH）VD、BALP等。对比治疗前后骨密度及骨代谢标志物变化。结果 用阿伦膦酸钠治疗6个月使绝经后2型糖尿病合并骨质疏松症患者的FBG、2hPG 、HbA1c降低,治疗前与治疗后相比较,差异有统计学意义（P〈0.05）。血Ca、P浓度治疗前与治疗后相比较,差异无统计学意义(P＞0.05)。骨代谢标志物CTX治疗前与治疗后相比,差异有统计学意义（P〈0.05）。OC 、PTH、BALP、25OHVD治疗前与治疗后相比较,差异无统计学意义(P>0.05)。治疗前腰椎和股骨颈骨密度与治疗后相比较,差异有统计学意义（P〈0.05）。Torch 、Ward部位骨密度治疗前与治疗后相比较,差异没有统计学意义(P＞0.05)。结论 阿伦膦酸钠治疗绝经后2型糖尿病合并骨质疏松症疗效明显,短时间内可改善骨代谢指标和提高腰椎骨密度。     

Biochemical effects of a single oral dose of calcium on bone metabolism in elderly Chinese women

Summary The biochemical effects of a single oral dose of 10 mmol of calcium on certain blood and urine variables were studied in 20 elderly postmenopausal subjects (mean age 72.3±6.2 years) with a very low dietary calcium intake (mean 7.2±3 mmol/day). Twelve hours after calcium administration, the plasma total calcium, phosphate and bicarbonate, and the urinary calcium/creatinine ratio rose, while the plasma parathyroid hormone and chloride, and urinary hydroxyproline/creatinine and phosphate/creatinine ratios fell. These results show that a single oral dose of calcium suppresses bone resorption in elderly women with low dietary calcium intake, and that long-term supplementation may be important in the prevention of osteoporosisrelated fractures.     

Effect of walking exercise on bone metabolism in postmenopausal women with osteopenia/osteoporosis

The purpose of this prospective study was to determine whether moderate walking exercise in postmenopausal women with osteopenia/osteoporosis would affect bone metabolism. Fifty postmenopausal women, aged 49–75 years, with osteopenia/osteoporosis were recruited: 32 women entered the exercise program (the exercise group) and 18 served as controls (the control group). The exercise consisted of daily outdoor walking, the intensity of which was 50% of maximum oxygen consumption, with a duration of at least 1h with more than 8000 steps, at a frequency of 4 days a week, over a 12-month period. Lumbar (L2–L4) bone mineral density (BMD) was measured at the baseline and every 6 months with dual-energy X-ray absorptiometry (DXA) in both groups. Serum bone-specific alkaline phosphatase (BAP) and urinary cross-linked N-terminal telopeptides of type I collagen (NTX) levels were measured at baseline and at months 1, 3, 6, 9, and 12 by EIA and ELISA, respectively, in the exercise group, and urinary NTX level was measured at the baseline and every 6 months in the control group. There were no significant differences in baseline characteristics including age, height, body weight, bone mass index, years since menopause, lumbar BMD, and urinary NTX level between the two groups. Although no significant changes were observed in lumbar BMD and the urinary NTX level in the control group, lumbar BMD in the exercise group was increased as compared with the control group, but was sustained from the baseline. In the exercise group, the urinary NTX level rapidly responded to walking exercise from month 3, and this reduction was sustained until month 12, followed by reduction in the serum BAP level. A moderately negative correlation was found between the percent change in the urinary NTX level at month 3 and that in lumbar BMD at month 12 in the exercise group. This study clearly demonstrates that the mechanism for the positive response of lumbar BMD to moderate walking exercise in postmenopausal women with osteopenia/osteoporosis appears to be the suppression of bone turnover, and that an early change in the urinary NTX level may be useful to predict the long-term response of increasing lumbar BMD to exercise, although its efficacy for lumbar BMD may be quite modest.     

Classification of osteoporosis in the elderly is dependent on site-specific analysis

Vertebral osteoporosis accounts for over 500,000 spinal fractures annually, the majority of which occur in older women. Despite these statistics, data regarding the rate of spinal bone loss in this population are conflicting. Moreover, the site of skeletal evaluation may significantly alter classification of osteoporosis in this age group. To examine trabecular-rich spinal bone loss with a measurement less affected by age-related artifacts that the AP spine, we measured lateral lumbar spine bone density (BMD) using dual-energy X-ray absorptiometry in 120 healthy, ambulatory, community-dwelling women 65 years of age and older (mean 70±5 years, range 65–88). We also examined cortical-rich sites in the forearm and total body along with AP spine and femoral BMD to assess the impact of site specificity using the World Health Organization (WHO) classification of osteoporosis. Significant losses in BMD were observed at the lateral spine (−1.1%/year,P<0.01), forearm (−0.77%/year,P≤0.01), total hip (−0.75%/year,P≤0.01), femoral neck (−0.70%/year,P≤0.05), and trochanter (−0.78%/year,P≤0.01), but not the AP spine. Using the WHO criteria, lateral spine BMD determinations classified 66% of women with osteoporosis in contrast to 29% using the AP projection. Osteoporosis was diagnosed in 55% of women using measurements of the femoral neck, 43% using the total radius, and 19% using the total body. We conclude that elderly women lose bone at trabecular-and cortical-rich sites (lateral spine and total radius, respectively) in addition to sustaining significant age-related bone loss at mixed cortical/trabecular sites such as the hip. Classification of osteoporosis in this age group more than doubles using lateral versus AP spinal projections, supporting the necessity of developing more uniform agreement on site-specific analyses.     

铁过载对绝经后骨质疏松患者骨密度和骨代谢的影响

目的 观察铁过载对绝经后骨质疏松患者骨密度和骨代谢的影响。方法 将234名绝经后妇女按照骨密度（bone mineral density, BMD）分为正常组、骨量减少组和骨质疏松组。分析铁过载对年龄、绝经年数、血钙(Ca)、磷(P)、体质量指数（bone mass index,BMI）、肝肾功能、葡萄糖代谢、脂质代谢、炎症反应、BMD、抗酒石酸酸性磷酸酶5b(TRACP-5b)、ALP、Ⅰ型胶原交联C端肽(β-CTX)和Ⅰ型胶原交联N端肽(PINP)的影响。结果 与正常组相比,骨量减少组和骨质疏松组血清铁蛋白(Fer)显著升高(P<0.05)。Fer水平与BMD呈负相关(P<0.05)。TRACP-5b水平在骨质疏松组明显高于正常组(P<0.05)。与正常组相比,骨质疏松症组的ALP水平显著升高(P<0.05)。与骨量减少组相比,骨质疏松组血清β-CTX水平明显升高(P<0.05);且骨质疏松组的PINP水平显著高于正常组(P<0.05)。更重要的是,血清Fer和PINP之间存在正相关(P<0.05);血清Fer和β-CTX之间呈正相关(P<0.05)。结论 铁过载对绝经后骨质疏松患者骨密度和骨代谢均有显著影响。     

老年男性原发性骨质疏松症患者血清性激素的变化

目的探讨血清多种性激素的变化对老年男性原发性骨质疏松的影响。方法182例老年男性患者测定腰椎及髋部骨密度(双能X线骨密度仪)，分为正常、骨量减少与骨质疏松组，40例健康青年男性为对照组。所有受试者用放射免疫法测定血清总睾酮(TT)、雌二醇(E2)、硫酸脱氢表雄酮(DHEAS)、性激素结合球蛋白(SHBG)，用免疫比浊法测定血清白蛋白，并计算游离睾酮(FT)、生物有效性睾酮(Bio-T)、游离雄激素指数(FAI)、游离雌二醇(FE2)及生物有效性雌二醇(Bio-E2)结果老年男性在股骨颈、Ward三角及大转子骨密度明显低于青年男性；随年龄的增长，除SHBG外，其他性激素均有明显下降；老年男性中，Bio—T及FAI在骨质疏松组明显降低，其他激素无明显变化。结论老年男性骨密度降低与增龄引起的性激素下降密切相关，而具有生物活性的睾酮的降低是影响老年男性原发性骨质疏松的重要因素。     

Age-dependent effects of atorvastatin on biochemical bone turnover markers: a randomized controlled trial in postmenopausal women

The use of HMG-CoA-reductase inhibitors (statins) has been associated with decreased risk of bone fractures in epidemiological studies. In vitro evidence suggests that statins may stimulate bone formation, but the data are still preliminary. We assessed the effects of the HMG-CoA-reductase inhibitor atorvastatin on biochemical parameters of bone metabolism in a multicenter, randomized, double-blind, placebo-controlled trial conducted between October 2001 and October 2002 in three hospital-based outpatient metabolism clinics. Forty-nine postmenopausal women, mean age 61 ± 5 years, mean time postmenopause 12.6 ± 8.8 years, were treated with atorvastatin, 20 mg per day (n=24) or matching placebos (n=25) for 8 weeks. Comparing the differences to baseline between the groups, there were no statistically significant effects of atorvastatin either on the bone formation markers intact osteocalcin and bone-specific alkaline phosphatase or on the bone resorption markers C-telopeptide and intact parathyroid hormone. The marker of bone fractures, undercarboxylated osteocalcin, was also unchanged. When analyzed in dependence of age, atorvastatin increased C-telopeptide and osteocalcin in the younger subjects, while it decreased them in older subjects. Most interestingly, in older subjects, atorvastatin caused a significant decrease in the ratio of C-telopeptide to osteocalcin, an indicator of bone remodeling, while the ratio was increased in younger subjects, suggesting beneficial effects on bone turnover exclusively in older individuals (approx. >63 years). In summary, the present data suggest that short-term treatment with atorvastatin may have age-dependent effects on biochemical markers of bone turnover in postmenopausal women.     

Effect of impact exercise on bone mineral density in elderly women with low BMD: a population-based randomized controlled 30-month intervention

Evidence of the effect of exercise on bone loss comes mainly from studies in voluntary postmenopausal women, and no population-based, long-term interventions have been performed. The purpose of this population-based, randomized, controlled trial was to determine the effect of long-term impact exercise on bone mass at various skeletal sites in elderly women with low bone mineral density (BMD) at the radius and hip. Participants ( n =160) were randomly assigned to 30 months either of supervised and home-based impact exercise training or of no intervention. The primary outcome measures were femoral neck, trochanter and total hip BMD, and the secondary outcomes were bone density measures at the radius and calcaneum. Outcomes were assessed at baseline, 12 months and 30 months using blinded operators. The analyses were performed on an intention-to-treat analysis. Mean femoral neck and trochanter BMD decreased in the control group [–1.1%, 95% confidence interval (CI) –0.1% to –2.1% and –1.6%, 95% CI –0.4% to –2.7%], while no change occurred in the exercise group. Mean trochanter BMC decreased more in the control group (–7.7%, 95% CI –9.7% to –5.6% vs. –2.9%, 95% CI –5.3 to –0.9). There were six falls that resulted in fractures in the exercise group and 16 in the control group during the 30-month intervention ( P =0.019). A significant bone loss occurred in both groups at the radius and calcaneum. In multivariate analysis, weight gain was associated with increased BMD and BMC at all femur sites both in the exercise group and in the pooled groups. In conclusion, impact exercise had no effect on BMD, while there was a positive effect on BMC at the trochanter. Exercise may prevent fall-related fractures in elderly women with low bone mass.There was no conflict of interest.     

Lumbar spine peak bone mass and bone turnover in men and women: a longitudinal study

Summary  Peak bone mass is an important determinant of bone mass in later life, but the age of peak bone mass is still unclear. We found that bone size and density increase and bone turnover decreases until age 25. It may be possible to influence bone accrual into the third decade. Introduction  Peak bone mass is a major determinant of bone mass in later life. Bone growth and maturation is site-specific, and the age of peak bone mass is still unclear. It is important to know the age to which bone accrual continues so strategies to maximise bone mass can be targeted appropriately. This study aims to ascertain the age of lumbar spine peak bone mass. Methods  We measured lumbar spine BMC, estimated volume and BMAD by DXA and biochemical markers of bone turnover in 116 healthy males and females ages 11 to 40, followed up at an interval of five to nine years. Results  The majority of peak bone mass was attained by the mid-twenties. Increases in BMC in adolescents and young adults were mostly due to increases in bone size. Bone turnover markers decreased through adolescence and the third decade and the decreasing rate of change in bone turnover corresponded with the decreasing rate of change in lumbar spine measurements. Conclusions  Skeletal maturation and bone mineral accrual at the lumbar spine continues into the third decade.     

类风湿关节炎患者血清骨代谢标志物水平及炎症因子变化研究

目的探讨类风湿关节炎(rheumatoid arthritis,RA)患者血清骨代谢标志物水平及炎症因子的变化。方法收集RA患者60例和健康对照者20名,再将60例RA患者按照是否合并骨质疏松(osteoporosis,OP)分为OP组(32例)和非OP组(28例)。采用双能X射线骨密度测量仪测骨密度,酶联免疫吸附法测定外周血清白细胞介素(interleukin,IL)-1β、IL-6、IL-17、I型前胶原N-末端前肽(N-terminal propeptide of type I collagen,PINP)、I型胶原C-末端交联顶端肽(type I collagen cross-linked Ctelopeptide,CTX)水平,并详细记录临床、实验室资料。对两组间计量资料采取独立样本t检验进行比较,采用Pearson积差相关法进行相关性分析。结果 (1)RA组与对照组相比,其骨密度、PINP水平普遍较低(P0.05);CTX、IL-1β、IL-17、IL-6水平普遍较高(P0.05)。(2)与非OP组相比,OP组的年龄、病程、IL-1β、IL-17、IL-6水平普遍较高(P0.05),OP组患者CTX、PINP水平虽然高于非OP组,但差异无统计学意义(P0.05)。(3)RA患者外周血血清中IL-1β与红细胞沉降率(erythrocyte sedimentation rate,ESR)成正相关(r=0.423,P0.05),IL-6与C反应蛋白(C-reactive protein,CRP)、ESR、类风湿关节炎患者病情评价(DAS28评分)成正相关(r=0.473、0.370、0.481,P0.05);IL-17与CRP、ESR、DAS28成正相关(r=0.411、0.367、0.468,P0.05);CTX与疾病活动性指标CRP、ESR、DAS28呈正相关(r=0.536、0.488、0.466,P0.05),与病程呈负相关(r=-0.268,P0.05);PINP水平与各疾病活动性指标间均无相关性(P0.05)。结论 RA患者存在较高的OP发生率,且合并OP患者IL-1β、IL-17、IL-6高于未合并OP患者,RA患者中继发OP作用机制可能与炎症因子IL-1β、IL-6、IL-17相关;CTX和PINP与疾病活动和OP密切相关,测定这两个骨代谢指标能够了解RA患者早期骨破坏程度。     

Prolonged bisphosphonate release after treatment in women with osteoporosis. Relationship with bone turnover

Bisphosphonates (BP), especially alendronate and risedronate, are the drugs most commonly used for osteoporosis treatment, being incorporated into the skeleton where they inhibit bone resorption and are thereafter slowly released during bone turnover. However, there are few data on the release of BP in patients who have received treatment with these drugs for osteoporosis. This information is essential for evaluating the possibility of BP cyclic therapy in these patients and for controlling their long-term presence in bone tissue. This study evaluated the urinary excretion of alendronate and risedronate in patients treated with these drugs for osteoporosis and analysed its relationship with bone turnover, time of previous drug exposure and time of treatment discontinuation. We included 43 women (aged 65 ± 9.4 years) previously treated with alendronate (36) or risedronate (7) during a mean of 51 ± 3 and 53 ± 3 months, respectively, who had not been treated with other antiosteoporotic treatment and with a median time of discontinuation of 13.5 and 14 months, respectively. Both BP were detected in 24-hour urine by HPLC. In addition, bone formation (PINP) and resorption (NTx) markers were analysed. Both BP were also determined in a control group of women during treatment. Alendronate was detected in 41% of women previously treated with this drug whereas no patient previously treated with risedronate showed detectable urinary values. All control patients showed detectable values of both BP. In patients with detectable alendronate levels, the time of drug cessation was shorter than in patients with undetectable values (12 [6–19] versus 31 [7–72] months, p < 0.001). Alendronate was not detected in any patient 19 months after treatment cessation. Alendronate levels were inversely related to time of treatment discontinuation (r = − 0.403, p = 0.01) and the latter was directly related to NTx (r = 0.394, p = 0.02). No relationship was observed with age, length of drug exposure, renal function or weight.In conclusion, contrary to risedronate, which was not detected in patients after cessation of treatment, alendronate was frequently detected in women previously treated with this agent up to 19 months after discontinuation of therapy. The relationship between alendronate levels and both bone resorption and time of treatment cessation further indicates a residual effect of this drug in bone, despite treatment discontinuation.     

骨代谢生化指标随年龄的变化及其临床意义

本文收集了北京地区１９２８名不同年龄（０～８７岁）健康人及５３４５例２０余种疾病患者空腹尿及血，并对其骨代谢生化指标进行测定。结果表明：血清２５羟基维生素Ｄ（２５ＯＨＤ），碱性磷酸酶（ＡＬＰ），骨钙素（ＢＧＰ），甲状旁腺激素（ＰＴＨ），尿Ⅰ型胶原交联Ｎ末端肽与肌酐比值（ＮＴＸ／Ｃｒ）及羟脯氨酸与肌酐比值（ＨＯＰ／Ｃｒ）与年龄显著相关。血清２５ＯＨＤ，ＢＧＰ，尿ＮＴＸ／Ｃｒ及ＨＯＰ／Ｃｒ可用于预测骨量。１，２５（ＯＮ）２Ｄ３，２５ＯＨＤ，ＮＴＸ／Ｃｒ和ＮＯＰ／Ｃｒ可用于区分绝经前与绝经后骨质疏松妇女。与年龄有关的骨丢失可能与１，２５（ＯＨ）２Ｄ３的降低、ＰＴＨ的升高及肾功能减退有关；绝经后骨丢失与雌激素缺乏有关。     

Forearm bone mass and biochemical markers of bone remodelling in normal Chinese women

We studied bone mineral content and density (BMC/BMD) and bone turnover markers in normal Chinese women from the age of 20 to 80 years and compared the data with those for normal women from the Western part of the world (Denmark). In all subjects (5 at each age;n=305) BMC and BMD were determined at three sites of the nondominant forearm with single X-ray absorptiometry (SXA). In addition, 10 women had five repeated measurements to determine the reproducibility of the equipment, demonstrating coefficients of variation of 1%–2% depending on the measurement site. The Chinese premenopausal women were on the average heavier (1 kg) than the postmenopausal women, but they were also taller (6 cm). The postmenopausal women had highly significantly less bone mass than the premenopausal women; 15% at the 1/4-distal site, 25% at the 8-mm-distal site, and 35% at the ultradistal site. At age 50, bone mass in Chinese women was very similar to that of a comparable group of Danish women. After age 50, bone loss accelerated and the rate of loss seemed more rapid in the Chinese than in the Danish women. Within the first 5 postmenopausal years, the most cortical part decreased by approximately 3.9%, the mixed cortical and trabecular site by 9.5%, and the mainly trabecular site by 16.2%. In the following 5 years the decreases were 6.3%, 5.5%, and 6.6%, respectively, and 5.6%, 11.3%, and 8.9% for year 11–15 after menopause. The bone decrement continued throughout the 25th year of menopause, and except for the ultradistal site, the rate of loss did not change very much. The postmenopausal women had highly significantly higher levels of all bone turnover markers than premenopausal women. The markers stayed high at all ages. We conclude that the present study gives the normal values of Chinese women's bone mass at three sites of the distal forearm. The data were collected in a way which allows them to be used as reference for normal Chinese women. The data demonstrate that women from the East and West are relatively similar in terms of bone mass.