骨质疏松人工智能技术研究进展及发展趋势

目的探讨人工智能(artificial intelligence,AI)技术在骨质疏松早期诊断、早期预防、标准化治疗及科学化随访中的应用现状及发展前景。方法查阅近十年人工智能在医学中的应用现状,分析探讨骨质疏松AI技术开发的可行性及其关键技术限制瓶颈。结果开发优质AI技术的重要前提是大量准确知识的学习。骨质疏松筛查AI技术需要大量的骨密度数据和流行病学因素调查作为筛查系统的数据基础,诊治和随访AI技术需要大量的专业术语、影像学数据、血液、尿液生化指标的采集学习。因此,学习和验证过程中重要的是需要大量的骨密度数据、流行病学调查因素、血液尿液生化指标数据、骨密度测定影像资料、骨质疏松诊断中的专业术语资料、骨质疏松治疗过程中的用药及治疗效果资料等。这些相关资料的收集过程可以通过骨质疏松生物样本库的构建完成。结论骨质疏松AI的开发离不开骨质疏松体检生物样本库的建设,高质量多中心大规模骨质疏松生物样本库构建过程中收集的大量可供机器人学习及再学习的资料是决定骨质疏松AI技术开发成败的关键。     

骨质疏松症诊断标准的探讨

本文目的是再次讨论骨质疏松的诊断标准问题。骨质疏松症的诊断以骨密度DXA检测为金标准。1994年世界卫生组织(WHO)推荐的骨质疏松诊断标准为:患者骨密度低于同性别人群峰值骨量均值2.5个标准差以上,或减少30%以上。这个标准的T值是根据年轻白人妇女计算的,但是对于不同地区是不能固守这一标准的。有研究调查我国部分地区骨质疏松症总患病率为32.3%(2.0SD)和14.9%(2.5SD),2种骨密度诊断标准计算骨质疏松症患病率差异有显著性,若以2.5SD为标准很可能造成漏诊。该研究者还发现骨质疏松症的患病率在老年远高于年轻人。而WHO采用的是白人年轻女性的数据库,它是否适用就更值得推敲。另有研究者以骨密度低于-2.0SD标准,推算杭州市妇女骨质疏松的发病率为29.5%。认为以-2.0SD为标准可以相对早期发现骨质疏松。还有研究对于高原的藏族人群进行检测,也得出同样结论。有研究者推算我国各个DXA仪器之间的换算公式,发现上述换算公式基本上与日本推出的相同,但是与美国推出的换算公式有差异。这都证明WHO骨密度诊断标准是否适用于黄种人是有疑问的。国内有研究者以BMD-2.0SD为诊断标准,结合以骨代谢生化指标,认为能全面合理评价骨转换。还有研究者对目前国内使用骨密度检测方法进行统计分析,发现60岁骨量丢失率有18%左右,70岁阶段达到22%左右。这个患病百分率比较符合中国人的实际情况。按照世界上基本通用的换算方法,1.0SD约等于10%～12%的骨量丢失百分率,因此建议男性骨质疏松诊断标准为骨量丢失率达到25%或2.0SD,实际诊断年龄在70岁以上。如果采用2.5SD,中国人患病诊断时间会推迟到70岁以后,尤其是男性要推迟到90岁以后。骨质疏松症的研究关键是正确合理的诊断,不同种族、不同国家或地区有不同的诊断标准。1994年以前全世界都执行WHO1985年提出的峰值骨量丢失2.0个标准差诊断为骨质疏松症。1994年WHO提出了白人妇女小于-2.5SD为骨质疏松,但也明确指出该标准仅适用于欧美白人妇女。以Orimo为首的日本骨代谢学会制定了日本人群的骨质疏松诊断标准:骨密度在同性别青年人平均值30%以下为骨质疏松,丢失20%～30%为骨量减少。1999年中国老年学学会骨质疏松委员会诊断学组建议骨质疏松的诊断标准为骨量丢失百分率达到25%,或者说2.0SD。对于国外也有学者倾向于采用-2.0SD的标准来评价骨质疏松症。有研究发现不同国家间,和每国内部不同人群和人种的骨密度是明显不同的。非洲和拉丁美洲人种的骨密度高于白种人,而白种人的骨密度则高于黄种人。总结:1、国内外人群间骨密度的差异是公认的,我国人群骨密度是低于制定国际标准的白种人的,有倾向以T值低于-2.0SD为骨密度诊断标准。但是大规模的流行病学调查比较研究还很少,有必要进一步提供更确切的骨质疏松诊断更改的流行病学依据。2、以2.0SD为标准可以减少骨质疏松的漏诊,对于流行病学人群调查筛选病例,进行危险因素分析和对骨质疏松高危人群进行干预实验尤为有必要。3、如果加强国内和国际间多单位的联合研究,可以提高标准制定的科学性和权威性。     

石河子地区中老年人群LRP5基因Q89R位点多态性与骨质疏松的关联性分析

目的本研究旨在探讨石河子地区中老年人群LRP5基因Q89R位点多态性与骨质疏松之间的关系。方法通过采用聚合酶链反应限制性片段长度多态性技术(PCR-RFLP)对115例健康汉族中老年人、74例骨量低下者和33例骨质疏松患者的LRP5基因Q89R位点进行分型,并计算其基因频率分布;全自动生化仪对生化指标进行检测;双能X线骨密度仪测定腰椎L1-L4和股骨颈、Ward’s三角区、大转子、股骨干的骨密度。结果中老年男性人群LRP5基因Q89R位点各基因型之间的骨密度、生化指标均无统计学差异。中老年女性LRP5基因Q89R位点QQ、QR、RR基因型总基因频率分别为82.14%、16.97%、0.89%;正常对照组分别为88.10%、11.90%、0%;骨量低下组分别为90.24%、9.76%、0%,骨质疏松组分别为62.07%、34.48%、3.45%,QQ、QR型在骨质疏松组与骨量低下组、正常对照组之间的基因频率存在显著性统计学差异;腰椎L1-L3、大转子的骨密度与Q89R基因型相关;未发现腰椎第四节、Ward’s三角区、股骨颈、股骨干的骨密度值与Q89R基因型具有相关性;生化指标中,血清磷含量与基因型显著相关。结论 LRP5基因Q89R位点多态性具有种族、地区差异性。LRP5基因Q89R位点基因多态性是石河子地区中老年女性骨质疏松的预测因素,提示LRP5基因是影响骨密度的候选基因之一。     

女性骨质疏松性骨折骨密度阈值及中国人群骨质疏松诊断标准探讨

目的研究河南地区女性骨质疏松性骨折骨密度阈值并进一步探讨中国人群骨质疏松诊断标准。方法收集465例女性骨质疏松性骨折患者的病历资料,对双能X线测定的骨密度值、T值、Z值进行统计分析。结果女性患者腰椎BMD值低于0.7955 g/cm2、T值低于-2.15、Z值低于-0.52时,骨折风险较高;髋部BMD值低于0.7270 g/cm2、T值低于-2.10、Z值低于-1.01时,骨折风险较高。结论对于骨密度低于上述阈值者,需高度警惕骨质疏松性骨折的发生,应采取积极有效的预防和治疗措施。WHO的骨质疏松诊断标准与中国人群的骨密度情况存在一定差异,因此,应展开全国范围的骨质疏松流行病学调查工作,健全中国人群骨密度数据库,为制定适合中国人群骨质疏松诊断标准提供流行病学依据。     

载脂蛋白E基因多态性与原发性骨质疏松症的相关性研究

目的探讨载脂蛋白E基因多态性与原发性骨质疏松症、骨质疏松性骨折的相关性。方法选出60例原发性骨质疏松患者,其中髋部骨折组30例均为新近骨折并有X线片为诊断依据,30例健康对照组性别、年龄与之对应。全部对象均行骨密度测定;采静脉血,EDTA抗凝;淋巴细胞分离液分离白细胞,置-80℃保存;分离的白细胞中提取DNA;基因位点DNA扩增;PCR扩增产物SSCP分析。结果骨质疏松组及骨质疏松性骨折组载脂蛋白E基因2型、3型、4型等位基因频率分别为0.05、0.80和0.15,0.1167、0.5667和0.3167,而30例健康对照组依次为0.10、0.8667和0.0333。载脂蛋白E基因4型等位基因频率三组比较差异有显著性(X2=17.520,P<0.01);骨质疏松组及骨质疏松性骨折组携带载脂蛋白E基因4型频率明显高于正常人群;骨质疏松性骨折组携带载脂蛋白E基因4型频率明显高于骨质疏松组。结论载脂蛋白E4与原发性骨质疏松症、骨质疏松性骨折有密切相关性;载脂蛋白E4是原发性骨质疏松症,尤其是骨质疏松性骨折一个有用的标志物。     

长春市汉族人群COL1A1启动子区多态性与骨质疏松症的相关性

目的研究长春市汉族人群Ⅰ型胶原α1链基因(COL1A1)启动子区-1997G/T、+1245G/T多态性及其与骨质疏松的关系。方法 (1)抽取受试人群外周静脉血5 ml,提取血清DNA。(2)应用实时荧光定量PCR仪扩增目的基因的DNA片段。(3)采用TaqMan探针法对-1997G/T及+1245G/T位点进行等位基因鉴别。(4)应用双能X线骨密度仪测定骨密度(BMD),将374例受试人群分为骨密度正常、骨质疏松、骨质疏松性骨折3组。结果长春市汉族正常人群COL1A1-1997G/T转换中,GG基因型占38.40%,GT基因型占46.38%,TT基因型占15.22%,以GT基因型为主;骨质疏松患者女性GG等位基因型所占比例大于男性,GG基因型占44.39%,GT基因型占43.37%,TT基因型占12.24%;骨质疏松骨折患者GG基因型为主,占47.50%,GT基因型占35.00%,TT基因型占17.50%。骨质疏松组女性GG基因型BMD低于GT、TT基因型,但差异无统计学意义(P均0.05);骨质疏松骨折组女性GG基因型BMD显著低于GT、TT基因型(P均0.05)。COL1A1+1245位点G/T转换,在正常人群中发现GT杂合型2例,占总数的0.53%,其余均为GG基因型。结论 COL1A1-1997G/T转换中正常人群以GT基因型为主,骨质疏松患者和骨质疏松骨折患者以GG基因型为主。骨质疏松患者和骨质疏松性骨折患者女性GG基因型BMD均低于GT、TT基因型。COL1A1-1997G/T与BMD显著相关,+1245G/T与BMD无相关性。     

遗传基因与骨质疏松症

骨质疏松症是一种多因素性疾病。主要特征是单位体积骨量减少,骨脆性增加。影响骨量的因素可分为环境因素与遗传因素两种。环境因素包括营养、运动及生活习惯等,是影响骨量的可控因素。近年来,随着分子生物学技术的研究进展,遗传因素对骨量和骨质疏松发病的影响,逐步引起人们的重视。家族性流行病学调查研究发现：双亲骨折史与子女的骨密度及家庭主要成员骨量之间存在明显相关性,说明正常人群峰值骨量及骨密度受遗传因素调控。国外学者Ｊｏｈｎｓｔｏｎ曾指出,人群骨量的差别２０％归于环境因素,８０％归于遗传因素［１］。但骨量究…     

陕西关中女性原发性骨质疏松患者I型胶原基因多态性研究

目的 从分子流行病学角度探讨陕西关中地区人群Ⅰ型胶原α1基因SPl位点多态性与原发性骨质疏松症、骨质疏松性骨折的相关性.方法 选取陕西关中地区无血缘关系汉族绝经后骨质疏松患者83例及健康女性98例,生物化学方法检测剔除任何其他影响骨代谢因素后,骨密度仪检测腰椎、股骨BMD,及限制性片段长度多态性(RFLP)方法检测其CoLⅠA1 SPl位点多态性.结果 所研究181例样本CoLⅠA1基因SP1位点均为SS,所选样本未发现CoLⅠA1基因SP1位点多态性存在.结论 陕西关中地区原发性骨质疏松女性患者与CoLⅠA1 基因SPl位点多态性无相关性.     

陕西关中女性原发性骨质疏松患者Ⅰ型胶原基因多态性研究

目的从分子流行病学角度探讨陕西关中地区人群Ⅰ型胶原α1基因SPl位点多态性与原发性骨质疏松症、骨质疏松性骨折的相关性。方法选取陕西关中地区无血缘关系汉族绝经后骨质疏松患者83例及健康女性98例,生物化学方法检测剔除任何其他影响骨代谢因素后,骨密度仪检测腰椎、股骨BMD,及限制性片段长度多态性(RFLP)方法检测其CoLⅠA1SPl位点多态性。结果所研究181例样本CoLⅠA1基因SP1位点均为SS,所选样本未发现CoLⅠA1基因SP1位点多态性存在。结论陕西关中地区原发性骨质疏松女性患者与CoLⅠA1基因SPl位点多态性无相关性。     

PTH基因多态性与骨质疏松性骨折的相关性研究

目的探讨甲状旁腺激素(parathyroid hormone,PTH)基因rs1459015位点多态性与北京地区汉族人群骨质疏松性骨折骨密度的关系。方法研究对象为北京地区无亲缘关系的汉族人群,其中骨质疏松性骨折患者(骨折组)127例,非骨质疏松性骨折患者(对照组)145例。采用SNaPshot法检验PTH基因多态性,双能X线吸收仪测定腰椎L2~4、股骨近端的neck、Ward’s三角、troch和total骨密度,计算两组等位基因频率、基因型频率,分析骨折组和对照组各部位骨密度差异以及骨折组PTH基因多态性与各部位骨密度的关系。结果骨折组A、G等位基因频率19.7%、80.3%,对照组A、G等位基因频率18.6%、81.4%,差异无统计学意义(P0.05)。两组AA、AG、GG基因型频率分别为3.9%、31.5%、64.6%和3.4%、30.3%、66.2%,差异无统计学意义(P0.05)。骨折组各部位骨密度均低于对照组,除neck骨密度差异外均有统计学意义(P0.05)。骨折组中GG基因型腰椎骨密度均高于AA、AG基因型(P0.05)。与AA、GG基因型相比,骨折组AG基因型髋部骨密度较高(P0.05)。结论PTH基因多态性rs1459015位点与北京地区汉族人群骨质疏松性骨折患者骨密度不相关。     

Prevalence of Osteoporosis Using DXA Bone Mineral Density Measurements at the Calcaneus: Cut-Off Points of Diagnosis and Exclusion of Osteoporosis

The objective of this article is to evaluate different T-score cut-off points in the calcaneus in order to establish the prevalence of osteoporosis in the general population and to evaluate the clinical value of bone mineral density at the calcaneus as a tool to identify patients with spine or hip osteoporosis. A total of 1455 people (727 women and 728 men) from the Hortega cohort were studied. The densitometric studies were carried out in the calcaneal region using a Peripheral Instantaneous X-ray Imaging (PIXI) Lunar bone densitometer. We established three cut-off points (-1.6, -2.0, -2.5). One-hundred twenty-five patients (67 men with a mean age of 47 +/- 13 yr and 58 women with a mean age of 66 +/- 8 yr) from internal medicine outpatient clinics who were undergoing densitometry of the calcaneus, spine, and hip were subsequently studied. The prevalence of osteoporosis in women with a calcaneus T-score -1.6 was 12.4%, which is comparable to the 12.7% obtained with an axial densitometer in a Spanish population. The prevalence in men was 7.8%, with a calcaneus T-score of <-2.0. In women, the highest sensitivity (85%) was obtained with a calcaneus T-score of <-1.0 and the highest specificity with a calcaneus T-score of <-2.5. In men, the best sensitivity (61%) was obtained with a calcaneus T-score of <-1.0 and the best specificity (98%) with a calcaneus T-score of <-2.5. A calcaneus T-score <-1.6 is an adequate cut-off to establish the prevalence of osteoporosis in population studies. In women, a calcaneus T-score of >-1.0 enables the diagnosis of the disease to be excluded, whereas a calcaneus T-score of <-2.5 enables the diagnosis to be confirmed and treatment to be initiated in both men and women.     

Comparison of Bone Mineral Density of the Phalanges, Lumbar Spine, Hip, and Forearm for Assessment of Osteoporosis in Postmenopausal Women

The objective of this study was to compare peripheral bone mineral density (BMD) of the phalanges with BMD of the lumbar spine, total hip, femoral neck, and forearm and to determine the clinical value of measuring a single peripheral site (phalanges) in identifying postmenopausal women with osteoporosis. BMD was measured by dual energy X-ray absorptiometry using the accuDEXA((R)) (ADXA-finger) (Schick, New York, NY) and the QDR-4500 (DXA-lumbar spine, hip, forearm) (Hologic, Waltham, MA). Correlation coefficients between ADXA and DXA of the lumbar spine, total hip, femoral neck and one third radial site ranged from 0.53 to 0.73. The sensitivity of an ADXA T-score of -2.5 in identifying patients with a DXA T-score of < or = -2.5 at the femoral neck was 35%. An ADXA T-score cut point of -1.0 improved the sensitivity of ADXA in identifying patients with a femoral neck T-score of < or = -2.5 (85%), but the specificity declined from 88 to 49%. There was substantial discordance in the diagnosis of osteoporosis when a single site was measured, regardless of technique. Within the limitations of single-site measurements, BMD measured by ADXA has adequate sensitivity to identify women with low BMD at the femoral neck, if an appropriate T-score criterion is used.     

Growth hormone increases bone mineral content in postmenopausal osteoporosis: a randomized placebo-controlled trial.

Eighty osteoporotic, postmenopausal women, 50-70 years of age, with ongoing estrogen therapy (HRT), were randomized to recombinant human growth hormone (GH), 1.0 U or 2.5 U/day, subcutaneous, versus placebo. This study was double-blinded and lasted for 18 months. The placebo group then stopped the injections, but both GH groups continued for a total of 3 years with GH and followed for 5 years. Calcium (750 mg) and vitamin D (400 U) were given to all patients. Bone mineral density and bone mineral content were measured with DXA. At 18 months, when the double-blind phase was terminated, total body bone mineral content was highest in the GH 2.5 U group (p = 0.04 vs. placebo). At 3 years, when GH was discontinued, total body and femoral neck bone mineral content had increased in both GH-treated groups (NS between groups). At 4-year follow-up, total body and lumbar spine bone mineral content increased 5% and 14%, respectively, for GH 2.5 U (p = 0.01 and p = 0.0006 vs. placebo). Femoral neck bone mineral density increased 5% and bone mineral content 13% for GH 2.5 U (p = 0.01 vs. GH 1.0 U). At 5-year follow-up, no differences in bone mineral density or bone mineral content were seen between groups. Bone markers showed increased turnover. Three fractures occurred in the GH 1.0 U group. No subjects dropped out. Side effects were rare. In conclusion, bone mineral content increased to 14% with GH treatment on top of HRT and calcium/vitamin D in postmenopausal women with osteoporosis. There seems to be a delayed, extended, and dose-dependent effect of GH on bone. Thus, GH could be used as an anabolic agent in osteoporosis.     

Prevention and treatment of glucocorticoid-induced osteoporosis in 2005

Concern about glucocorticoid-induced osteoporosis is warranted in all patients who take glucocorticoids for longer than 3 months, in any dosage. Bone mineral density should be measured and additional risk factors sought in order to determine whether bisphosphonate therapy is appropriate. Bisphosphonate therapy should be considered in postmenopausal women and in patients whose bone densitometry T-score is less than -1.5.     

苏州地区老年人疾病史与骨质疏松的相关性研究

目的通过流行病学调查苏州市社区老年人疾病史与骨质疏松的相关性。方法采用现场问卷调查了解受试者的基本资料(包括性别、年龄、身高、体重)及疾病史(包括高血脂及用药、胃/十二指肠切除、甲亢/甲低、肾功能不全、贫血、恶性肿瘤、皮质激素使用和其他疾病),并用双能X线骨密度仪(Hologic Wi)测量5 527例大于65岁老年人群的髋部、腰椎和股骨颈骨密度(bone mineral density,BMD)T值,然后以骨密度T值为因变量进行一元回归分析及全子集回归变量选择,并使用广义线性回归模型基于Elastic Net进行多元因变量选择。结果切除胃/十二指肠、其他骨科疾病及是否服用降血脂药纳入以髋部骨密度T值为因变量的最优模型(调整的判定系数最优)。高血脂、甲亢/甲低、肾功能不全、贫血纳入以腰椎BMD T值为因变量的最优模型(调整的判定系数最优);切除胃/十二指肠、肾功能不全、贫血纳入以股骨颈骨密度T值为因变量的最优模型(调整的判定系数最优); Elastic Net变量筛选,提示高血脂、长期服用降血脂药、切除胃/十二指肠、肾功能不全、贫血、恶性肿瘤、长期服用皮质激素及其他骨科疾病与骨密度T值具有相关性,短期服用皮质激素与骨密度T值没有相关性。结论在老年群体中,多种疾病的病史与骨质疏松密切相关,提示患有所列疾病的65岁以上老年人需定期进行BMD测量和疾病筛查,以有效预防骨质疏松的发生。     

Screening with ultrasound of the heel may contribute to the prevention in osteoporosis

<正> Objective:To calibrate a Quantitative Ultrasonography(QUS)system against densitometryby defining the sensitivity and specificity of the method,and to propose a series of QUS interpre-tation thresholds to classify the individual risk with regards to the risk of developing osteoporosisin later life.Methods:Subjects were recruited in New York City over a 1-year period.Women with amen-orrhea for at least 12 months were defined as postmenopausal,and all other women as premeno-pausal.Bone mineral density(BMD)was measured with a dual energy X-ray absorptiometer(DXA)and QUS performed with the calcaneus of broadband ultrasound attenuation(BUA)andspeed of sound(SOS)using the Lunar Achilles system.Statistical analysis was performed usingSPSS software Version 10.0.Results:Two hundred twenty-eight premenopausal and menopausal women were recruited.Most of the participants were Hispanic,Caucasian and African-American in this study.All thesubjects had DXA and QUS examined and T-score was got from both.The statistical resultsshowed that the T-score of QUS has a significant relationship with that of DXA(spine:r=0.557,P<0.0001;femur:r=0.611,P<0.0001).Both QUS and DXA T-score has a significant andnegative relationship with age(QUS:r=-0.241,P<0.0001;Spine:r=-0.277,P<0.0001;femur:-0.296,P<0.0001).When T-score of heel ultrasound -1.5 was set as the interpreta-tion threshold,the osteoporosis patients with T-score of DXA-femur scan(100%)and DXA-spine(77.10%)less than -2.5 were detected.As well,the specificities of T-score -1.5 ofQUS for DXA-femur and DXA-spine were 67.5% and 72.8%,respectively.In addition,if we set-1.0 of T-score of QUS as the cutoff,74.80% and 79.60% of the osteopenia based on DXA ofspine and femur were identified.The specificities were 59.4% and 57.7%.Conclusions:QUS of the calcaneus may be an effective method for providing risk stratifica-tion for osteoporosis,and for the closely associated future risk for fragility-fracture.     

The Assessment of Bone Mass in Men

Bone mineral density (BMD) is widely used in postmenopausal women to identify who should be given therapy for prevention and treatment of osteoporosis and to monitor the efficacy of treatment. There is still uncertainty about how to interpret BMD in men, and few prospective studies exist on the relationship between BMD and fracture risk. Men should be considered for measurement of BMD if they have suffered low trauma fractures, have prevalent vertebral deformities, have radiographic osteopenia, are over age 75, or have conditions that increase their risk for bone loss, such as hypogonadism, glucocorticoid use, or generally poor health. There is insufficient information to recommend a more widespread BMD screening. The World Health Organization has developed criteria for interpreting BMD which are widely used. Patients with BMD at least 2.5 SD below the young adult mean (T-score < -2.5) have osteoporosis, and those with BMD between 1 and -2.5 SD below the young adult mean (-2.5 < T-score < -1.0) have osteopenia. However, the BMD criteria that should be used to identify men in need of therapeutic intervention are still debated. Using male-specific hip BMD cutoffs, approximately 3-6% of U.S. men 50 years and older were estimated to have osteoporosis and 28-47% to have osteopenia. The corresponding figures in women were 13-18% with osteoporosis and 37-50% with osteopenia. Greater accumulation of skeletal mass during growth, slower rate of bone loss, and shorter life expectancy in men contribute to the lower prevalence of osteoporosis relative to women.     

Bone mineral density (BMD) assessment of central skeletal sites from peripheral BMD and ultrasonographic measurements: an improved solution employing age and weight in type 3 regression.

The objective of this study was to develop a method whereby bone mineral density measurements of the heel and finger, as well as ultrasonographic measurements of calcaneal sound transmission, could identify individuals with a diagnosis of osteoporosis or osteopenia by the World Health Organization criteria for these diagnoses in the central skeleton (i.e., the lumbar spine (LS) and hip [femoral neck] [FN]). Two hundred and forty-four women in a university hospital laboratory setting had dual-energy X-ray absorptiometry measurements of bone mineral density (BMD) in the calcaneus, finger, hip, and spine, and quantitative ultrasound of the calcaneus. Regression equations were developed to predict central bone mineral T-scores from T-scores of peripheral measurements, adjusted by age and weight. Equations were validated by predicting the cut point for osteopenia at the lumbar spine and hip (T-score=-1.0). Ninety-five percent confidence intervals of the mean predicted LS or FN T-score from each peripheral site included -1.0. We conclude that our derived regression equations (taking into account interaction of peripheral BMD with patient age and weight) are useful for predicting T-scores in the central skeleton. This approach reduces the potential for misdiagnosis, which can result if one uses unadjusted peripheral T-scores, which are only moderately correlated with the central measurements of BMD.     

Bone Mineral Density After Simultaneous Kidney-Pancreas Transplantation: Four Years Follow-up of 57 Recipients

Bone disease and an high risk of fractures are major problems in transplantation. Among diabetic patients undergoing simultaneous kidney-pancreas (SKP) transplantation, there are few studies assessing long-term effects on bone mass. The aim of this study was to evaluate bone mineral density (BMD) over 4 years follow-up after SKP transplantation. Fifty-seven patients had 22.8 ± 5.3 years of prior diabetes, 65% were female, and the overall mean age was 24.3 ± 5.93 years. At the time of transplantation, the lumbar spine and femoral neck T-scores were −1.75 ± 1.05 and −1.95 ± 0.73, respectively; 28% of subjects had evidence of osteoporosis. One year after transplantation, 77.6% of patients displayed improved lumbar T-scores to −1.33 ± 0.94 (P = .044) with stable femoral neck T-scores. Bone densitometry enhanced gradually through the 4 years follow-up: lumbar T-score to −1.04 ± 0.67 (P = .004) and femoral neck T-score to −1.69 ± 0.49 (P = .12). At year 4, no osteoporosis cases were detected but 86.7% of patients did not receive steroids in the immunosuppressive regimen. The graft function remained stable (serum creatinine, 1.2 mg/dL; fasting glucose, 87.7 mg/dL). During the follow-up, BMD improved more significantly at cortical sites. Our study reports a reduced prevalence of fractures (8.7%) compared with the literature, which could be related to a steroid-sparing protocol and/or aggressively treatment of osteoporosis.