有氧运动对超重青少年骨密度的影响

目的分析青少年体成分与骨密度的关系,探讨生活方式干预对超重青少年骨密度及体成分的影响。方法选取北京市城区1所中学共117名健康青少年,年龄11.08～15.17岁,男:女54:63,进行人体测量学指标测定,使用双能X光吸收仪测定骨密度(BMD)、肌肉质量及脂肪比率。受试者按BMI分为正常体重组(30人)和超重组(87人)。超重组(BMI:22.4～34.09kg/m2)按干预方式被随机分为饮食组(D)、运动组(EX)、饮食加运动组(DEX)及对照组(C),进行10周干预。干预结束后复测上述指标。结果女生BMD显著高于男生(P<0.01),未发育者BMD较已发育者低(P<0.05),正常体重组与超重组间BMD差异无统计学意义(P>0.05)。BMD与年龄、身高、体重、BMI、胸围、臀围、全身肌肉质量呈正相关(r=0.206～0.329,P<0.05);与腰围、全身及躯干体脂率无明显相关性(P>0.05)。干预后D、EX及DEX组体重、BMI、腰围、臀围、WHR均显著下降,与干预前比较差异有统计学意义(P<0.01),C组体重和BMI无明显变化(P>0.05);D、EX及DEX组干预后全身及各部位脂肪含量均显著下降(P<0.01);EX组及DEX组BMD均显著增加(P<0.01,P<0.05),D组及C组BMD无明显变化(P>0.05)。(EX+DEX)组BMD平均增加(0.017±0.027)g/cm2,明显高于非运动组(D+C)BMD平均变化(0.008±0.047)g/cm2(P<0.01);而饮食干预组(D+DEX)组与非饮食干预组(EX+C)组BMD差异无统计学意义(P>0.05)。结论青少年阶段骨密度随年龄、身高和体重的增加而增加,并存在性别差异。骨密度增加与机体肌肉质量呈正相关,与脂肪比率无明显关系。有效的饮食和运动干预均可减轻体重和脂肪比率,运动可促进骨密度增加。对超重青少年应积极进行包括有氧运动在内的生活方式干预。     

住院老年患者骨骼肌减少与骨密度的关系

目的探讨住院老年患者骨骼肌质量、骨骼肌指数与骨密度的关系,以及骨骼肌减少与骨质疏松的关系,为老年骨质疏松及脆性骨折患者的临床防治开拓新思路。方法连续选取重庆医科大学附属第一医院住院老年患者562例,测量身高、体重,计算体重指数(BMI),利用双能X线骨密度仪(DXA)测量不同部位骨密度(BMD)和T值、四肢骨骼肌质量(ASMM)、骨骼肌指数(RSMI)、脂肪百分比(fat%),用Pearson相关性分析法研究各变量之间的关系,用Logistic回归法研究骨骼肌减少、骨质疏松、脆性骨折的关系。结果不同性别老年患者RSMI均与BMD显著正相关(腰椎:男性r=0.203,P0.01,女性r=0.165,P0.01;髋部:男性r=0.253,P0.01,女性r=0.225,P0.01),且均与BMI呈高度正相关性(男性r=0.777,P0.01;女性r=0.791,P0.01),BMD亦与BMI呈显著正相关(腰椎:男性r=0.319,P0.01,女性r=0.236,P0.01;髋部:男性r=0.199,P0.01,女性r=0.211,P0.01)。老年女性骨质疏松和脆性骨折患病率明显高于男性,而老年男性骨骼肌减少的检出率则显著高于女性。老年男性骨骼肌减少与骨质疏松存在明显的相关性(β=0.774,P=0.002,OR=2.168),而老年女性二者无明显相关性。结论骨质疏松与骨骼肌减少存在性别差异,老年男性二者存在明显正相关,老年女性二者无显著相关;脆性骨折与骨质疏松及骨骼肌减少均密切相关,增加肌肉量对老年人群骨质疏松及骨折的防治有重要意义。     

骨质疏松性骨折人群跌倒风险、骨密度、肌力和体脂的相关性

目的探讨骨质疏松性骨折人群的骨密度与跌倒风险、体质量指数(body mass index,BMI)、肌力、体脂含量的相关性。方法通过对4 632例社区45岁以上绝经后女性的问卷调研及骨密度筛查,筛查出既往有脆性骨折史的骨质疏松性骨折人群。测定骨质疏松性骨折人群的骨密度、身高、体质量、跌倒风险、肌力和腹部脂肪含量。采用Spearman检验分析跌倒指数、体脂含量、年龄、身高、体质量、BMI与骨密度(bone mass density,BMD)之间的相关性。BMD校正年龄、身高、体质量、BMI、体脂含量,采用ANCOVA分析跌倒指数对BMD的影响;校正年龄、身高、体质量、BMI、跌倒指数,分析体脂含量对BMD的影响。结果对筛查出的839例骨质疏松性骨折患者的BMD、BMI、跌倒风险、腹部体脂含量、肌力等相关性分析结果显示,骨质疏松性骨折人群BMI、跌倒指数、肌力与BMD均显著相关(BMI r=0.161,跌倒指数r=0.238,肌力r=0.198,P均0.001)。BMI、肌力、跌倒风险与BMD呈正相关;校正年龄、身高、体质量、BMI等因素,采用ANCOVA分析跌倒指数与BMD无显著相关(F=1.011,P0.05)。结论跌倒风险和低BMD为骨折的主要危险因素。本研究显示体脂含量与BMD呈显著相关性。     

体成分对不同糖耐量绝经后女性骨密度影响的研究

目的观察体成分对正常糖耐量(NGT)及2型糖尿病(T2DM)绝经后女性骨密度(BMD)的影响及差异。方法收集中南大学湘雅二医院2005—2008年长沙地区152名绝经后女性志愿者及门诊就诊者,经OGTT检测41例诊为T2DM,111名糖耐量正常,年龄45～81岁。采用双能X线骨密度仪测定腰椎前后位腰1至腰4(AP)、左侧股骨颈(FN)、左髋部总体(T-hip)及全身骨密度(TBMD),同时测定体成分,计算出瘦体重(LTM)、体脂量(FTM)、躯干体脂比(Tru-fat%)及总体脂比(Fat%)。分析体成分对两组研究对象BMD的影响。结果体成分对不同糖耐量绝经后女性BMD的影响存在差异。NGT组:瘦体重与各部位BMD均呈正相关,是各部位BMD的独立预测因素(β=0.199～0.455,R2C=0.027～0.200,P0.01或0.05),体脂比与全身BMD呈负相关,体脂为全身BMD(β=-0.237,P0.05)的独立影响因素。T2DM组:瘦体重仅与股骨颈及髋部BMD呈正相关,总体脂比与股骨颈及髋部BMD呈正相关,体脂为股骨颈及髋部BMD(β=0.427～0.475,R2C=0.166～0.182,P0.01)的独立影响因素,而瘦体重与各部位BMD均无独立相关。结论绝经后女性中,相对于NGT组,T2DM组的瘦体重对BMD的保护作用减弱,体脂对股骨颈及髋部起到保护作用;糖尿病超重或肥胖患者减重过程中,需要加强肌肉力量的锻炼,并保持适当的体重,以防止骨量丢失。     

绝经后女性雌激素水平与骨质疏松症和动脉粥样硬化风险相关性研究

目的探讨绝经后女性雌激素水平与骨质疏松症和动脉粥样硬化的关系。方法选择沈阳市健康汉族女性216例,根据月经史分为4组,绝经前组57例,绝经1~10年组69例,绝经11~20年组36例及绝经>20年组54例。采用ELISA法检测血清雌激素水平。采用骨矿物质密度(BMD)与腰椎、髋部T值评价骨代谢情况。动脉粥样硬化评估指标包括踝肱指数(ABI)、肱踝脉搏波传导速度(baPWV)及颈动脉内膜中层厚度(CIMT)。结果与绝经前组比较,绝经后各组baPWV及CIMT明显升高,髋部和腰椎BMD明显降低,绝经>20年组ABI显著降低(P<0.01)。绝经后女性平均雌激素水平与绝经时间呈负相关(r=-0.423,P<0.01)。雌激素水平与腰椎、髋部BMD和腰椎、髋部T值呈正相关(r=0.556,P<0.01;r=0.490,P<0.01;r=0.620,P<0.01;r=0.523,P<0.01)。雌激素水平与ABI呈正相关,与baPWV和CIMT呈负相关(r=0.228,P<0.01;r=-0.250,P<0.01;r=-0.203,P<0.05)。结论绝经后女性雌激素水平与骨质疏松症和动脉粥样硬化风险密切相关。     

2型糖尿病患者骨骼肌量与骨折风险的相关性

目的探究2型糖尿病患者骨骼肌量与骨折风险的关系。方法选取2014年1月至2015年9月在东南大学附属中大医院内分泌科住院治疗的2型糖尿病患者106例,男性44例,女性62例,平均年龄(58.1±12.9)岁,应用双能X线吸收检测仪(dual energy X-ray absorptiometry,DXA)行体成分分析及骨密度(bone mineral density,BMD)测定,通过问卷调查获取患者基础信息,采用骨折风险预测工具FRAX模型计算患者10年任何重要部位骨质疏松性骨折(major osteoporotic fracture,MOF)概率、髋部骨折(hip fracture,HF)概率,并采用亚洲人骨质疏松自我筛查工具(osteoporosis self-assessment tool for Asians,OSTA)模型计算骨折风险,分析骨折风险、各部位骨密度与四肢和躯干肌肉量、骨骼肌指数(relative skeletal muscle index,RSMI)、全身体脂率、年龄、糖尿病病程、糖化血红蛋白(glycosylated hemoglobin,HbA1c)等指标的相关性。控制性别、年龄、病程、HbA1c及各部位BMD,对骨折风险和身体成分各指标行偏相关分析。结果偏相关结果显示:总体MOF与总肌肉百分比呈正相关(r=0.223);HF与躯干肌肉量、总肌肉量/(身高)2呈负相关(r=-0.240、-0.255),与总肌肉百分比呈正相关(r=0.225)。老年女性患者,MOF与躯干肌肉量、全身总肌肉量、总肌肉量/(身高)2、RSMI呈负相关(r=-0.396、-0.382、-0.443、-0.393);躯干肌肉量、双下肢肌肉量、全身总肌肉量、总肌肉量/(身高)~2、RSMI与HF呈负相关(r=-0.512、-0.436、-0.478、-0.558、-0.446),与OSTA呈正相关(r=0.842、0.688、0.803、0.694、0.574),相关性与总体比较,差异均有统计学意义(均P0.05)。结论 2型糖尿病患者肌肉量是其骨折风险的影响因素,增加肌肉量、控制血糖水平对2型糖尿病患者骨质疏松及骨折的防治具有重要意义。     

健康青年人体成分对局部和全身骨密度的影响

目的探讨北京地区健康青年人脂肪组织质量(fat mass,FM)和肌肉组织质量(lean mass,LM)对局部和全身骨密度(bone mineral density,BMD)的影响。方法使用双能X线吸收法测定上肢、大腿、躯干和全身的骨密度、体脂率(fat percentage,Fat%)、脂肪组织质量和肌肉组织质量。根据体质量指数分为正常体质量组、超质量组和肥胖组。Pearson相关分析和偏相关分析探索各部位BMD与全身和局部体脂率、脂肪组织质量和肌肉组织质量之间的关系。结果共纳入80名19.4~31.0岁的健康受试者。Pearson相关分析显示男性上肢、大腿和全身BMD与全身体脂率(上肢r=0.185,P=0.252;大腿r=0.069,P=0.674;全身r=0.181,P=0.263)和局部体脂率(上肢r=0.141,P=0.386;大腿r=0.025,P=0.876)及全身FM(上肢r=0.294,P=0.065;大腿r=0.163,P=0.316;全身r=0.302,P=0.059)和局部FM(上肢r=0.290,P=0.069;大腿r=0.155,P=0.340)均无显著相关关系,但女性各部位BMD与全身体脂率(上肢r=0.581,P=0.000;大腿r=0.449,P=0.004;躯干r=0.677,P=0.000;全身r=0.631,P=0.000)、局部体脂率(上肢r=0.477,P=0.002;大腿r=0.386,P=0.014;躯干r=0.689,P=0.000)、全身FM(上肢r=0.683,P=0.000;大腿r=0.615,P=0.000;躯干r=0.797,P=0.000;全身r=0.775,P=0.000)和局部FM(上肢r=0.669,P=0.000;大腿r=0.616,P=0.000;躯干r=0.778,P=0.000)均呈显著正相关。但控制年龄、性别和体质量指数后,上肢、大腿和全身BMD仅与全身LM(上肢r=0.266,P=0.020;大腿r=0.372,P=0.001;躯干r=0.312,P=0.006;全身r=0.371,P=0.001)和局部LM(上肢r=0.391,P=0.000;大腿r=0.443,P=0.000)呈显著正相关。结论肌肉组织质量是影响青年人各部位BMD的主要因素。     

老年男性2型糖尿病患者骨密度及相关因素分析

目的 探讨老年男性2型糖尿病患者骨质疏松发病的危险因素. 方法 应用双能X线骨密度仪测定80例老年男性2型糖尿病患者的腰椎和股骨骨密度.并检测血清和尿液中骨代谢及血糖相关的生化指标,分析影响患者骨密度的相关危险因素. 结果所有患者中依据任一部位的骨密度值,骨质疏松的检出率为18.6%,骨量减少的检出率为53.8%.体质量和体质量指数(BMI)与腰椎、股骨颈和Ward's三角的骨密度呈正相关(r=0.202～0.298,P<0.05或P<0.01),年龄、糖化血红蛋白(HbAlc)与腰椎和股骨颈的骨密度呈负相关(r=-0.172～-0.211,均P<0.05).瘦素除与股骨颈和Ward's三角骨密度呈正相关外,尚与体质量、BMI、空腹血糖、血清总胆固醇、HbAlc相关(r=0.219～0.509,P<0.05或P<0.01).多元逐步回归分析显示,体质量是所有部位骨密度的影响因素,HbAlc影响股骨颈骨密度,瘦素影响Ward's三角区骨密度(r~2=0.196～0.276,均P<0.01). 结论 老年男性2型糖尿病患者中,不同部位的骨密度受不同的因素影响.     

老年人患慢性病的数量与脂肪、肌肉等体成分的相关性研究

目的探讨老年人患慢性病的数量与脂肪、骨骼肌等人体成分的相关性。方法纳入2017年3月至6月期间在北京某三甲医院进行常规体检的60岁以上老年人474名。采用生物电阻抗法(BIA)对其进行人体成分测量,并调查其患各种慢性病的情况,对两者进行相关性分析。采用SPSS 17.0进行数据处理。计量资料的组间比较采用t检验。运用Spearman相关分析法分析患慢性病数量与各人体成分指标间的相关性。结果老年人患慢性病的数量与年龄具有高度正相关性(r=0.75,P0.01),与性别没有相关性(r=-0.01,P0.05)。剔除年龄、性别因素后,患慢性病的数量与内脏脂肪面积、躯干脂肪量、体脂百分比三者存在高度正相关性(r=0.71、0.61、0.60,P0.01);与体脂量相关性低(r=0.21,P0.01);与上、下肢脂肪量无相关关系(r=-0.06、0.03,P0.05);而与骨骼肌质量、四肢骨骼肌质量指数(ASMI)、四肢骨骼肌质量、躯干骨骼肌质量存在中度负相关性(r=-0.51、-0.50、-0.53、-0.53,P0.01);与BMI、基础代谢率、蛋白质、骨矿物质存在中度或高度负相关性(r=-0.60、-0.56、-0.42、-0.65,P0.01);与腰臀比(WHR)存在低度正相关性(r=0.23,P0.01)。结论老年人患慢性病的数量与年龄、内脏脂肪关系最密切,其次是全身的骨骼肌、BMI、营养;而与四肢脂肪量、WHR相关性差。老年人除了应注意维持下肢肌肉量,还要充分重视核心肌群的锻炼,以减少内脏脂肪。同时老年人在营养上要注意补充蛋白质和矿物质。     

老年2型糖尿病女性代谢综合征与骨质疏松的关系

目的探讨老年2型糖尿病女性代谢综合征(MS)与骨质疏松(OP)的关系。方法 85例老年2型糖尿病女性分为OP组及非骨质疏松(non-OP)组,比较两组的基本情况、代谢组分及骨密度(BMD)。Pearson相关分析分析BMD与代谢组分的相关性。Logistic回归分析OP的影响因素。病人再分为MS组和非MS(non-MS)组,比较两组的BMD及OP患病率。结果 OP组较non-OP组的年龄、脉压(PP)、总胆固醇(TC)、尿酸(UA)、纤维蛋白原(Fg)高(P<0.05或P<0.01),而体重指数(BMI)、双股骨、L1⁴BMD低(P<0.05或P<0.01)。双股骨BMD与年龄、TC、Fg负相关,与BMI正相关;L14BMD低(P<0.05或P<0.01)。双股骨BMD与年龄、TC、Fg负相关,与BMI正相关;L1⁴BMD与年龄、TC、TG负相关,与BMI正相关。OP的影响因素为TC,PP,BMI。MS组和non-MS组的BMD及OP患病率的差别无统计学意义(P>0.05)。结论老年女性2型糖尿病的MS与OP的关系复杂,今后应围绕胰岛素抵抗在基础和临床方面进行两者关系的研究。     

The relationship between body composition and bone mineral density in postmenopausal Turkish women

In a retrospective cross-sectional study among 202 postmenopausal women aged 46–75 years, we aimed to investigate the relationship between body composition and bone mineral density (BMD) to determine whether fat mass or lean mass is a better determinant of BMD in Turkish postmenopausal women. Lumbar spine (L1–L4) and proximal femur BMD were measured by dual energy X-ray absorbsiometry. Body composition analysis was performed by bioelectric impedance method and fat mass, lean mass, and percent fat were measured. Both fat mass and lean mass were positively correlated with BMD at the lumbar spine and proximal femur, weight and body mass index. Lean mass was also positively correlated with height and negatively correlated with age and years since menopause (P < 0.01). The correlations of fat mass and lean mass with BMD at the lumbar spine and proximal femur remained significant after adjustment for age, years since menopause and height. When the lean mass was adjusted together with age, years since menopause and height, the significant relationship between the fat mass and BMD continued, however the significant correlation between the lean mass and BMD disappeared at all sites after adjustment for fat mass. In multiple regression analyses, fat mass was the significant determinant of all BMD sites. Our data suggest that fat mass is the significant determinant of BMD at the lumbar spine and proximal femur, and lean mass does not have an impact on BMD when fat mass was taken into account in Turkish postmenopausal women.     

The relationship between serum resistin, leptin, adiponectin, ghrelin levels and bone mineral density in middle-aged men

OBJECTIVE: Body weight is a significant predictor of bone mass. Hormonal factors such as sex hormones, insulin, leptin and adiponectin are thought to play a role in the mechanisms controlling the association of body weight and fat mass with bone mass. However, contradictory results have been reported for the association between serum adipocytokines and bone mineral density (BMD). We therefore examined whether the serum adipocytokine and ghrelin levels, markers of fat metabolism, are associated with BMD in male adults. PATIENTS AND MEASUREMENTS: For 80 male adults (average age 54.5 +/- 6.4 years; average body mass index (BMI) 24.4 +/- 2.5 kg/m2), the correlations between serum resistin, leptin, adiponectin and ghrelin levels with BMD were investigated. RESULTS: Among the adipocytokines, serum resistin levels were negatively correlated with lumbar spine BMD (r = -0.237, P = 0.05). After adjustment was made for age and BMI, log-transformed serum leptin showed a significant negative correlation with lumbar spine BMD, which was not seen on bivariate analysis (r = -0.237, P = 0.039). Femoral neck BMD was marginally associated only with serum adiponectin levels (r = -0.226, P = 0.062). In multiple regression analyses, among the adipokines, only resistin was a significant determinant of lumbar spine BMD, although the variance was small (R2 = 0.256). Serum ghrelin levels were not correlated with the BMD of either body site. CONCLUSIONS: Serum resistin level showed a significant negative correlation with lumbar spine BMD, although the variance was small. Further studies are needed to elucidate the role of adipocytokines in bone metabolism.     

Relationship of body composition with prevalence of osteoporosis in central south Chinese postmenopausal women

Objectives To elucidate the relationship between body composition and bone mineral density (BMD) and the prevalence of osteoporosis in central south Chinese postmenopausal women. Methods A cross‐sectional study was conducted on 954 healthy central southern Chinese postmenopausal women, aged 50–82. Total body, lumbar spine and left femur BMD and total body soft tissue composition were measured by dual X‐ray absorptiometry. Results Among the study population, 578 (60·5%) subjects were without osteoporosis and 376 (39·4%) subjects were osteoporotic. The osteoporotic women were older, shorter and thinner, had an earlier age at menopause, a lower BMD and bone mineral content (BMC) of the total body and at different sites, and had lower body mass and body mass components than the women without osteoporosis. Both fat mass and lean mass were positively correlated with age at menopause, height, weight, body mass index (BMI) and BMD at all sites. Fat mass and lean mass were also inversely correlated with age and years since menopause (P < 0·05). After controlling for age, age at menopause and height, both fat mass and lean mass were positively correlated with BMD at the lumbar_1–4 spine, the femoral neck and the total hip. Fat mass was the most significant determinant of BMD at the lumbar_1–4 spine with a higher R² change and a partial R² compared with that of lean mass, while lean mass had more impact on the total hip values. Either a fat mass below 18·4 kg or a lean mass below 33·9 kg was correlated with a higher prevalence of osteoporosis at the lumbar spine or total hip. Conclusions In central south Chinese postmenopausal women, both fat mass and lean mass are correlated with BMD at the lumbar spine and hip. Fat mass was the most significant determinant of BMD at the lumbar spine, while lean mass had more impact on the total hip value. Both lower values of fat mass and lean mass are related to a higher prevalence of osteoporosis at either the lumbar spine or the total hip. Thus, it is important to maintain a reasonable body weight to balance bone health and other metabolic disorders.     

Serum sclerostin levels were positively correlated with fat mass and bone mineral density in central south Chinese postmenopausal women

Objectives To investigate the relationship between serum sclerostin level, body composition, and bone mineral density (BMD) in central south Chinese postmenopausal women. Methods A cross‐sectional study was conducted on 260 healthy central southern Chinese postmenopausal women with vs without osteoporosis, aged 50–76 years old. Dual X‐ray absorptiometry was used to measure the bone mineral content and BMD of the whole body, lumbar spine and left femur, and total body soft tissue composition. Serum sclerostin levels were measured by a quantitative sandwich enzyme‐linked immunosorbent assay. Results Compared with women without osteoporosis, osteoporotic women had a significantly lower level of serum sclerostin (P = 0·001). Serum sclerostin levels were positively correlated with body weight, Ponderal index and fat mass. There was a positive correlation with the BMD of both the whole body and at various sites (P < 0·05), even after controlling for age, age at menopause, height and body weight. Multiple linear stepwise regression analysis showed that serum sclerostin level was the most significant determinant of both whole‐body and lumbar spine BMD, compared with age, age at menopause, fat mass and lean mass. Age had similar impact as serum sclerostin on hip BMD. Conclusions This study showed that in central south Chinese postmenopausal women, serum sclerostin is lower in women with osteoporosis than without. Serum sclerostin is positively correlated with fat mass and BMD for the whole body, lumbar spine and hip.     

Factors affecting bone mineral density in men

In this study, in 131 men aged 20–75 years, we investigated correlations between bone mineral density (BMD) in the lumbar spine and femoral neck and endogenous factors (age, body mass index) as well as exogenous factors (calcium intake, physical activity, smoking, caffeine, socioeconomic and educational levels). The age had a negative effect on femoral neck BMD in patients overall, and on both lumbar spine and femoral neck BMD in patients under 50. Physical activity has effects on femoral neck BMD in men above 50. Lumbar vertebral BMD negatively correlated with smoking in patients overall, and this correlation persisted when patients aged 50 and older were analyzed separately. Femoral neck BMD was positively correlated with body mass index in men aged 50 and older. Given the variety of findings in the research literature regarding risk factors for low BMD, we suggest that genetic and geographic factors should be considered.     

健康和骨折女性骨矿密度及其骨折阈值的测定

目的初步确定天津市女性骨矿密度（ＢＭＤ）正常参考值范围，探讨骨质疏松的诊断标准及骨折危险阈值。方法用双能Ｘ线吸收法（ＤＥＸＡ）对４５２例健康女性和５５例绝经后骨折患者ＢＭＤ进行测定。结果腰椎２～４、股骨和全身ＢＭＤ峰值分别在３０～３９、２０～２９和４０～４９岁。ＢＭＤ与年龄、绝经年限呈负相关（均为Ｐ＜０．０１），以绝经后最初５年的降低率最高；ＢＭＤ与身高呈正相关，６０岁以上妇女的体重和脂肪量与各部位ＢＭＤ呈正相关（Ｐ＜０．０５或０．０１）。以２０～４０岁女性腰椎ＢＭＤ均值减２．５标准差（ｓ）为界限值（０．８３ｇ／ｃｍ２），５５例骨折患者中４６例（８３．６％）腰椎ＢＭＤ低于界限值。结论该界限值作为女性骨质疏松诊断标准和脊椎骨折危险阈值可能较为合理。     

Circulating osteoprotegerin and receptor activator of NF-kappaB ligand system are associated with bone metabolism in middle-aged males

OBJECTIVE: Osteoporosis is a growing health problem in males as well as in females. Sex hormones and insulin-like growth factor-I (IGF-I) have been shown to be the major determinants in male bone metabolism. Osteoprotegerin (OPG) is a recently identified cytokine that acts as a decoy receptor for the receptor activator of NF-kappaB ligand (RANKL). OPG and RANKL have been shown to be important regulators of osteoclastogenesis. However, the relationship between the OPG-RANKL system and male bone status in human populations are unclear. Thus, the aim of this study was to investigate the relationship between the OPG-RANKL system and bone mineral metabolism in males. PATIENTS AND MEASUREMENTS: Serum concentrations of OPG, RANKL, oestradiol, total testosterone and IGF-I and bone mineral density (BMD) were measured in 80 Korean males aged 42-70 (mean age, 54.5 year). Enzyme-linked immunosorbent assays were used to determine the serum concentrations of OPG and RANKL. Serum concentrations of oestradiol, total testosterone, IGF-I and bone turnover markers were determined using standard methods. BMD at the lumbar spine and femoral neck were measured by dual energy X-ray absorptiometry. RESULTS: We observed a significant negative correlation between the serum OPG levels and lumbar spine BMD (r =-0.259, P < 0.05) in Spearman correlation analysis. Serum OPG levels and RANKL/OPG ratios were found to be significantly correlated to the serum osteocalcin levels (r =- 0.254, P < 0.05; r = 0.264, P < 0.05) in Spearman correlation analysis. Serum OPG levels were found to be negatively correlated with serum oestradiol levels (r =-0.319, P < 0.01) in Spearman correlation analysis. In addition, a significant positive correlation was found between serum RANKL/OPG ratios and oestradiol levels (r = 0.374, P < 0.001) in Spearman correlation analysis. In contrast, Serum total testosterone and IGF-I levels were not correlated with serum OPG levels or RANKL to OPG ratios in Spearman correlation analysis. In a multiple regression analysis, age, body mass index (BMI), and serum OPG levels were identified as a significant predictor for lumbar spine BMD, and age, BMI, serum OPG and RANKL levels for femoral neck BMD. In another multiple regression analysis, only serum oestradiol level was identified as a significant predictor for serum OPG or RANKL levels. In contrast, Serum total testosterone and IGF-I levels were not correlated with serum OPG or RANKL levels in multiple regression analysis. CONCLUSIONS: Our data show that the circulating OPG-RANKL system is associated with bone metabolism in the male populations. Also, our data suggest that OPG and RANKL may be mediators of the effects of oestradiol in male bone metabolism.     

Correlation between bone mineral density and plasma lipids in Taiwan

Many studies showed that depression is correlated with osteoporosis, while others showed that low cholesterol level is also related to depression. However, these relationships still remain controversial. Since the bone mineral density (BMD) is related to depression and depression is related to hypocholesterolemia, there might exist a correlation between BMD and plasma cholesterol levels. To prove this, we enrolled 5000 individuals, 2170 males, and 2830 females, who had health check-ups at a private clinic between 1998 and 1999. They were divided into three groups. Group 1 was composed of male subjects; Group 2, female subjects; and Group 3, females aged over 50 to exclude pre-menopausal females. Each subject had a routine physical examination, fasting blood drawing, BMD measured by dual energy x-ray absorptiometry (DEXA) over the wrist, and was given a questionnaire to answer. Between Groups 1 and 2, the females were significantly younger, had higher body mass index (BMI), total cholesterol (TC), high density lipoprotein cholesterol (HDLC), low density lipoprotein cholesterol (LDLC), and platelet, but lower BMD, fasting plasma glucose (FPG), triglycerides (TG), hemoglobin (Hgb), and white blood cell (WBC) count. As for Groups 1 and 3, all the aforementioned findings still remained the same except that the systolic blood pressure (SBP) was higher and diastolic blood pressure (DBP) was lower in Group 3. Our results showed that BMD is negatively related to age in males. In females, it is negatively correlated with age, FPG, PPG, SBP, DBP, TC, LDLC, TG, and Hgb, but positively related to BMI and platelet. However, for females in Group 3, BMD is only negatively related to age, FPG, SBP, and TG but positively related to BMI. Stepwise multiple regression analysis showed that the BMD is negatively related to age but positively related to BMI in both males and females. In Group 3, BMD is negatively related to age and FPG but positively related BMI. In conclusion, no correlation exists between BMD and cholesterol. This implies that the depression is not significantly related to cholesterol and/or BMD. This might be due to various confounding factors, which could affect their relationships. The negative correlation between BMD and FPG is only observed in females older than 50 years. Further studies are needed to clarify these relationships.     

Fitness,fatness and activity as predictors of bone mineral density in older persons

OBJECTIVES: To determine relationships of bone mineral density (BMD) with fitness, physical activity, and body composition and fat distribution. DESIGN: Cross-sectional. SETTING: General Clinical Research Center, Johns Hopkins Bayview Medical Center, Baltimore, Maryland. SUBJECTS: Men (n = 38) and women (n = 46), aged 55-75 years with high normal blood pressure or mild hypertension but otherwise healthy. METHODS: Aerobic fitness (oxygen uptake) on a treadmill, muscle strength by one-repetition maximum, activity by questionnaire, abdominal obesity by magnetic resonance imaging; anthropometrics, and body composition by dual energy X-ray absorptiometry (DXA) which measured total fat and lean mass, and BMD for the total skeleton, lumbar spine (L1-L4) and total hip. RESULTS: Aerobic fitness did not correlate with BMD. Using multivariate analysis to ascertain independent contributions to the variance in BMD, in women, with adjustment for hormone replacement therapy (HRT), total skeleton BMD was independently related to muscle strength and abdominal total fat; total hip BMD to body weight; lumbar spine BMD to abdominal total fat. HRT also influenced BMD in the lumbar spine. In men, lumbar spine BMD was independently related to abdominal total fat physical activity and total hip BMD related to lower body strength. P < 0.05 for all of these correlations. CONCLUSIONS: Abdominal obesity and muscle strength emerge as predominant correlates of BMD in older persons with stronger relationships seen in women. Body weight and HRT also explained portions of the variance in BMD in women. Whether abdominal obesity is simply a marker for general obesity or has independent protective effects on bone is yet to be determined.     

Knee isokinetic strength and body fat analysis in university students

Many factors such as anthropometric variables influence strength performance. This study is to determine the relationship between knee isokinetic strength and body composition, and to compare the gender differences. Test-retest reliability had been performed within one week for all measurement methods before the formal study. Fifty-eight 20-25 year-old university students, 32 females and 26 males, participated in this study. Isokinetic strength of the knee flexion and extension was measured at two angular velocities of 60 degrees/sec and 120 degrees/sec. Body composition was measured by bioelectrical impedance analysis (BIA) and skinfold caliper. The others variables including height, body weight, body mass index (BMI), and waist to hip ratio were measured or calculated. The results showed that the intra-class correlation coefficients for isokinetic knee strength were between 0.83 and 0.93, and body composition and anthropometric variables were between 0.83 and 0.98. Isokinetic knee strength was significantly correlated with body height, body weight, BMI, waist and hip ratio and percent of body fat estimated by skinfold caliper (r = -0.56 to 0.64). The correlation between isokinetic strength with percent of body fat estimated by BIA (r = -0.60 to -0.74; p < 0.001) and with fat free mass (r = 0.64 to 0.78; p < 0.001) was even higher. Although male subjects had significantly greater mean values in body height, body weight, waist to hip ratio and isokinetic strength than female subjects, the MANCOVA showed that the effect of gender on knee isokinetic strength would be eliminated when the covariant variable, the percent of body fat measured by BIA and BMI was controlled in the analysis model. In conclusion, knee isokinetic strength was significantly negatively correlated with proportion of fat and positively correlated with fat free mass. The magnitude of strength difference between males and females could be explained by differences in body fat proportion and BMI in this study. Therapist would take the body fat composition, fat free mass, and BMI into consideration in knee muscle strength measurement. Less body fat and higher BMI will contain more fat free mass that produces more muscle strength.