Reduced bone mineral density and low parathyroid hormone levels in patients with the adult form of hypophosphatasia

Summary Hypophosphatasia is a heritable metabolic bone disease with characteristically reduced levels of alkaline phosphatase (ALP) in the blood, liver, kidney and bone. ALP levels are normal in the intestine and placenta. About 300 patients have been reported so far in the literature. Three kindreds with 52 known subjects are described here, whereby 12 subjects could be examined osteologically. Four subjects were patients and had clinical signs of the disease: spontaneous fractures of the metatarsals or femora and low ALP serum levels ranging between 8 and 23 U/1 (normal range 40–170 U/1). Four other members without fractures had reduced ALP levels; they might be carriers of the disease and develop symptoms later in life. The four remaining subjects had normal ALP levels and no signs of the disease. Serum levels of intact parathyroid hormone (iPTH) were found to be in the lower normal range and serum calcium levels in the upper normal range. There was a significant (P<0.05) negative correlation between iPTH and serum calcium levels (r=–0.78). Urinary calcium excretion was increased in 3 subjects with fractures. 25-OH-D₃ levels were increased in 6 of 8 subjects without any treatment. The bone mineral density (BMD) was measured using dual X-ray absorptiometry of the lumbar spine, representing mainly trabecular bone, and single-photon absorptiometry of the forearm, measuring mainly cortical bone. Z-scores of the spinal bone mass ranged between 0.38 and –1.95 SD; Z-scores of the forearm bone mass ranged between 0.53 and –2.47 SD with the lowest values in patients with fractures. There was a significant (P<0.05) correlation between serum ALP levels and forearm BMD (r=0.83). We conclude from these data that patients with the adult form of hypophosphatasia have decreased forearm and subnormal spinal bone mass, as well as reduced serum levels of iPTH.Abbreviations BMD bone mineral density - ALP alkaline phosphatase - iPTH intact parathyroid hormone - 25-OHD₃ 25-hydroxyvitamin D₃ - SD standard deviation - PEA phosphoethanolamine - PPi inorganic pyrophosphate - PLP pyridoxal-5-phosphate - cDNA clonal desoxyribonucleic acid - U/S Ca²⁺ urinary/serum calcium - DXA dual X-ray absorptiometry - DPA dual photon absorptiometry - SPAD bone density of distal forearm measured by single photon absorptiometry - SPAP bone density of proximal forearm measured by single photon absorptiometry     

Evaluation of methods for prediction of bone mineral density by clinical and biochemical variables in perimenopausal women

Objectives: to predict spinal and femoral bone mineral density (BMD) in perimenopausal women from simple clinical and biochemical variables. Methods: 2016 women 3–24 months past last menstrual bleeding. Mean age 50.1±2.8 years. Age, height, weight, number of full term pregnancies, weekly hours of physical activity, sunbathing habits, use of sun bed, daily intake of calcium and vitamin D, smoking habits, consumption of alcohol, coffee, and tea, history of forearm or femoral neck fractures among the parents, serum osteocalcin (S-OC), serum bone specific isoenzyme of alkaline phosphatase (BSAP), and urine hydroxyproline/creatinine ratio (U-OHP) were used as predictors in three different mathematical models. Lumbar spine (L2–L4) and femoral neck BMD were measured by DEXA. Three mathematical models (multiple regression, logistic regression, and discriminant analysis) were applied. Results: the multiple regression explained 19–21% of the total variation, and the logistic regression and discriminant function had a sensitivity between 53 and 67% with specificity ranging from 67 to 80%. Age, S-OC, serum bone specific alkaline phosphatase, and a maternal history of forearm or femoral neck fractures seemed to be reproducible risk factors for low bone mineral density irrespective of the mathematical model applied. When applied to a separate population, the models performed poorly. Conclusions: Simple clinical and biochemical variables are not useful to predict spinal and femoral BMD in the individual perimenopausal woman.     

Association between depression and bone mineral density in community-dwelling older men and women in Korea

Objectives

Previous research suggested a significant correlation between depression and osteoporosis, but little is known for the elderly Asian population. We investigated an association between depression and bone mineral density (BMD) in the Korean elderly.

Study design

Cross-sectional data analysis of a community-based study, Kangwha Island, South Korea.

Main outcome measures

BMD, measured at the os calcis using a quantitative ultrasound device, was expressed as stiffness index and T-score. Depressive symptoms were evaluated by the Korean version of Beck Depression Inventory (K-BDI). Depression was defined as a K-BDI score of 16 or higher. Participants also completed a questionnaire, including demographic factors, metabolic abnormalities, and health-related lifestyle factors.

Results

A total of 932 local residents (422 men and 510 women) aged 60–80 years completed the questionnaires and baseline BMD evaluation. Men with depression had a significantly lower stiffness index compared to those without depression in an age-adjusted (77.2 ± 5.2 vs. 86.0 ± 1.5, p = 0.002) and a multivariate-adjusted model (78.5 ± 5.2 vs. 85. 9 ± 1.5, p = 0.007). Correspondingly, men with depression had an increased probability of having an osteoporosis (T-score ≤ −2.5) compared to those without depression; the age-adjusted odds ratio was 2.86 (95% CI, 1.36–6.01) and the multivariate-adjusted odds ratio was 2.69 (95% CI, 1.26–5.76). However, no significant association was observed in older women.

Conclusions

Depression was significantly associated with lower BMD in Korean older men, but not in women.     

Hip bone mineral density is improved by high-impact aerobic exercise in postmenopausal women and men over 50 years

Fifteen men and women (six men) between the ages of 50 and 73 years were recruited to begin keep-fit classes. They were matched for sex, age, menopausal status and mass to 15 non-exercising controls. The keepfit classes were two to three times a week and included high-impact exercise, including step and jumping exercises specifically to load the proximal femur and spine. Proximal femur, lumbar spine and total body bone mineral density (BMD) were measured at 0 and 12 months. Urinary pyridinoline (Pyr) and deoxypyridinoline (dPyr) crosslinks were measured every 6 months to assess bone resorption. Quadriceps isometric strength was measured every 6 months. BMD increased non-significantly at the femoral neck [1.57 (0.8%] and Wards triangle [1.97 (1.4%], and significantly at the greater trochanter 2.21 (0.9)% (P=0.02) in the exercise group. Femoral neck BMD decreased by −1.9(0.8)% (P=0.049) in the control group, which was significantly different from the change in the exercise group (P=0.009). BMD did not change at the Wards triangle or trochanter in the controls. Lumbar spine BMD did not change in either group. Total body BMD did not change in the exercise group, but decreased by −0.79 (0.3)% (P=0.02) in the controls. Follwing 6 months of the exercise classes, Pyr and dPyr crosslinks were significantly reduced [−19.0 (7.2)%;P=0.0019 and −20.0 (7.7)%;P=0.021 respectively]. There was no significant change in crosslinks after 1 year, and no change at any time in the controls. Quadriceps strength changed by 5.4 (3.7)% in the exercise group and by −6.9 (2.5)% (P=0.01) in the control group after 12 months, being significant between groups (P=0.008). This study suggests that high-impact, aerobic exercise in postmenopausal women and men over 50 years old is feasible and effective at maintaining muscle strength and increasing proximal femur BMD but not spine or total body BMD.     

Relationship between blood pressure levels and bone mineral density in postmenopausal Turkish women

Introduction

We investigated the association between bone mineral density (BMD) detected by dual-energy X-ray absorptiometric (DXA) method and blood pressure (BP) in a large sample of postmenopausal women.

Material and methods

The current study was based on a retrospective analysis of 586 postmenopausal women with a mean age of 60.8 ±8.8 years, who were screened for osteopenia or osteoporosis by DXA. Patients with hypertension (HT, n= 306) were compared with normotensive (NT, n = 290) individuals. Bone mineral density results for the femur neck and spine were classified into 3 groups according to World Health Organization criteria: normal (T score > –1.0 SD), osteopenia (T score –1.0 to –2.5 SD) and osteoporosis (T score < –2.5 SD). Patients with osteopenia or osteoporosis (T score < –1.0 SD) were grouped as having low bone mass (LBM).

Results

There were no significant differences in femur T score, femur BMD, femur Z score, spinal T score, spinal BMD and spinal Z score between hypertensive and normotensive groups. The group of patients with low bone mass calculated from femur T scores had higher age, systolic BP, duration of hypertension and duration of menopause, but lower BMI. Similarly, patients with low spine BMD had higher age and duration of menopause, but lower BMI. Linear regression analysis showed a significant correlation between systolic BP and femur BMD and T score values. Furthermore, logistic regression analysis revealed that hypertension is an independent predictor of spinal osteopenia and osteoporosis.

Conclusions

The presence of hypertension is an independent predictor of spinal low bone density in Turkish women after menopause.     

雌激素受体基因多态性与老年妇女的骨密度

背景：雌激素受体α基因多态性与骨质疏松的发生相关有一定的关系,但是对于危险基因型的研究还存在商榷余地。 目的：分析雌激素受体基因多态性与老年妇女骨密度的相关性。 方法：选择检查的老年健康妇女120例,提取全血基因组DNA,选择限制性内切酶PvuⅡ和XbaⅠ进行酶切,分析基因型的分布与频率。同时选择双能X射线骨密度仪测股骨颈、大转子及Ward三角处的骨密度值。 结果与结论：XbaⅠ酶切基因型XX 6例,Xx 78例,xx 36例;PvuⅡ酶切PP 32例,Pp 50例,pp 38例。不同基因型老年妇女的年龄、绝经年龄与体质量指数值对比差异无显著性意义(P > 0.05)。PvuⅡ酶切PP基因型妇女的大转子与ward三角处的骨密度值明显大于Pp及pp妇女(P < 0.05);而XbaⅠ酶切基因多态性在老年妇女中股骨颈、大转子与Ward三角的骨密度均无显著差异(P > 0.05)。说明雌激素受体基因多态性与老年妇女骨密度有一定的相关性,P等位基因对老年妇女大转子与Ward三角处的骨密度的维持有一定作用。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：     

Bone mineral density in healthy Tunisian women

Interpretation of densitometric results requires a comparison with reference bone mineral density (BMD) values of normal age and sex-matched persons. Thus the aim of this study was to determine these values for healthy Tunisian women, to estimate the prevalence of osteoporosis and to compare our findings with other populations. A cross-sectional study of 1378 Tunisian women aged between 20 and 96 years was carried out using DXA (GE-Lunar Prodigy). Subjects with suspected conditions affecting bone metabolism were excluded. Measurements were taken at the lumbar spine and femoral neck. These values were expressed at T-scores, with reference to the mean BMD values of the group aged 20–40 years. The peak bone mass, estimated in this age group was 1.174 + 0.127 g/cm² at the lumbar spine and 1.016 ± 0.118 g/cm² at the femoral site. It was attained respectively within the age of 25 years and 36 years. For both sites, the expected decline in BMD was shown when the successive age groups [40–49 years] and [50–59 years] were compared. Bone loss was rapid during the first 5 years after menopause. Thereafter BMD declined slowly but continually. The prevalence of osteoporosis in the women over 50 years of age, taking account of peak bone mass observed in our cohort, was 23.3% at the spine and 17.3% at the femoral neck with a combined prevalence of 23.4%. These rates attained respectively 30.4%, 11.8% and 32.9% when we considered the Italian values, which demonstrate the variability of osteodensitometric depending to the reference population adopted.     

广州地区绝经后妇女维生素D受体基因多态性与骨密度关系的研究

目的：了解广州地区绝经后妇女维生素D受体基因多态性的分布，并进一步研究其与骨密度的关系。 方法：应用聚合酶链反应-限制性片段长度多态性（PCR-RFCP）等生物学技术检测203例绝经后广州地区妇女维生素D受体(VDR)基因型，同时用双能X线骨密度测量仪检测腰椎、股骨颈、瓦氏三角、大转子处骨密度（BMD）。 结果：203例受试对象中，VDR基因型分别为BB型17例（占8.3%）、Bb型60例（占29.6%），bb型126例（占62.1%）， b等位基因频率为76.85%、B等位基因频率为23.05%，基因型分布符合Hardy-Weinberg定律。分析其基因型与骨密度的关系显示：只有bb与Bb、BB基因型在腰椎骨密度存在差异（P<0.05）、Bb与BB的腰椎BMD无差异（P>0.05），其余部位3种基因型骨密度无差异（P>0.05）。 结论： VDR基因型与BMD间存在着一定关联，但尚不能作为预测广州绝经后妇女发生骨质疏松危险性的遗传标志。     

乌鲁木齐市维吾尔族青年与老年女性血清微量元素及骨密度的对比

 背景：雌激素通过影响骨骼细胞的新陈代谢而促进微量元素在骨骼中的储存,影响骨密度的变化。 目的：比较乌鲁木齐市维吾尔族青年女性与老年女性骨密度及血清中微量元素的差异。 方法：使用MEDILINK生产的双能X射线骨密度测量仪对乌鲁木齐市维吾尔族30-40岁(青年女性组)与60-70岁(老年女性组)女性各30人进行骨密度测定;使用美国贝克曼库尔特生产的Unicel Dxc 800 Synchron生化检验仪查血清中的微量元素钙、磷、镁、铁、铜、锌含量。比较不同年龄段女性血清中微量元素及骨密度水平。 结果与结论：维吾尔族青年女性组骨密度显著高于老年女性组(P < 0.001);维吾尔族青年女性组血清微量元素锌显著低于老年女性组(P < 0.001);其余的血清微量元素钙、磷、镁、铁、铜两组之间差异无显著性意义(P > 0.05)。结果表明维吾尔族女性不同年龄段骨密度随体内血清中部分离子元素的改变有较大的改变。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

Kinematics of the lumbar spine in elderly subjects with decreased bone mineral density

Lumbar spine kinematics was studied in subjects with normal bone mineral density, osteopenia and osteoporosis to determine the effect of bone mineral density and morphology on the flexion–extension movement patterns of the lumbar spine. Lateral radiographs and skin-mounted electromagnetic motion tracking sensors were employed to study lumbar spine kinematics using a Bayesian Belief Network model. The predicted angular displacement of the vertebrae had a high correlation (r = 0.91, p < 0.001) with the actual movements. The overall mean error was −0.51° ± 3.11°. Intervertebral angular displacement and velocity consistently increased from L1/L2 to L5/S1. Differences were observed in the movement pattern between normal subjects and those with decreased bone density. In normal subjects, vertebral angular acceleration consistently decreased from the upper to the lower vertebrae but the same consistent predictable pattern was not observed in the subjects with decreased bone mineral density. It is possible that these changes in kinematic behaviours are related to morphological changes as well as altered neuromuscular functions.     

Effect of natural early menopause on bone mineral density

OBJECTIVES: Early menopause (EM) is included among the risk factors for osteoporosis. Several studies have shown that women with early menopause have lower bone mineral density (BMD) than those with normal expected age of menopause. The aim of our cross-sectional study was to investigate the effects of time of menopause on vertebral bone mass in healthy postmenopausal women and to evaluate if early menopause is a risk factor for lower vertebral BMD. METHOD: We studied 782 who had never received drugs acting on bone mass. The study population was divided into three groups: women with early, normal (NM), and late (LM) menopause. Our study population was further categorized in 5-year age segments between 45 and >75. RESULTS: The three groups examined did not differ for age, age at menarche, body mass index (BMI), and vertebral BMD, while there were significant differences in age at menopause and years since menopause. Our study showed that women with EM presented significantly lower vertebral BMD than NM and LM in 50-54 age segments. Beyond 55 years, EM, NM, and LM women had no differences in lumbar BMD values. CONCLUSIONS: In conclusion, controversial data demonstrated that the absolute amount of bone loss is greater after early menopause than after normal or late menopause, even if a slight effect of early menopause on bone mass cannot be excluded.     

雌性去卵巢大鼠体脂、瘦素与骨密度关系的初步探讨

本文旨在探讨体脂与骨量的关系,以及调节体脂的瘦素对骨的作用。选用6月龄雌性Wistar大鼠40只,随机分为两组,一组切除双侧卵巢,另一组行假手术。饲养2月后采用ELISA检测血清中瘦素浓度,检测大鼠体质量、腹腔内脂肪含量,DEXA测定大鼠股骨骨密度(BMD)。结果提示大鼠体质量在去卵巢组增加明显(P<0.05),腹腔内脂肪量在去卵巢后增加不明显(P=0.499),脂肪细胞分泌的瘦素两组之间没有差异(P=0.166),去卵巢组单位体质量的骨矿含量(BMC)较假手术组明显降低(P=0.003)。第8周体质量在假手术组与单位体质量BMC负相关,在去卵巢组与BMD正相关,假手术组腹腔内脂肪含量及瘦素浓度与单位体质量的BMC呈负相关关系。因此,体脂、瘦素与单位体质量BMC相关。     

Prospective evaluation of bone mineral density among middle-aged HIV-infected and uninfected women: Association between methadone use and bone loss

Objective

We undertook a prospective study to assess the impact of HIV infection on BMD in a cohort of HIV-infected and uninfected women that included illicit drug users, and to measure the contribution of traditional risk factors as well as HIV-related factors to loss of BMD over time.

Methods

We analyzed BMD at baseline and after ≥18 months in 245 middle-aged HIV-infected and 219 uninfected women, and conducted linear regression analysis to determine factors associated with annual BMD change at the femoral neck, total hip and lumbar spine.

Results

HIV-infected women had lower baseline BMD at the femoral neck and total hip compared with controls; unadjusted rates of BMD change did not differ by HIV status at any site. In multivariable analyses, we found that HIV seropositivity without protease inhibitor (PI) use was associated with BMD decline at the lumbar spine (−.009 g/cm² per year, p = .03). Additional factors associated with BMD decline were: postmenopausal status, lower BMI, and methadone use at the lumbar spine; postmenopausal status and hepatitis C seropositivity at the femoral neck; and postmenopausal status, age, smoking, and lower BMI at the total hip (all p < .05). Among HIV-infected women, ≥3 years of PI use was associated with an increase in lumbar spine BMD (.013 g/cm² per year, p = .008).

Conclusions

Bone loss among HIV-infected middle-aged women was modest, and possibly mitigated by PI use. Methadone use was associated with BMD decline, and should be considered when evaluating women for osteoporosis risk.     

Meta-analysis of genome-wide linkage studies for bone mineral density

Genome-wide linkage studies have shown several chromosome loci that may harbor genes that regulate bone mineral density (BMD), but results have been inconsistent. A meta-analysis was performed to assess evidence for linkage of BMD across whole genome scan studies. Eleven whole-genome scans of BMD or osteoporosis containing 3,097 families with 12,685 individuals were included in this genome scan meta-analysis (GSMA). For each study, 120 genomic bins of ~30 cM were defined and ranked according to maximum evidence for linkage within each bin. Bin ranks were weighted and summed across all studies. The summed rank for each bin was assessed empirically for significance using permutation methods. A total of seven bins lie above the 95% confidence level (P=0.05) and one bin was above the 99% confidence level (P=0.01) in the GSMA of eleven linkage studies: bins 16.1 (16pter-16p12.3, Psumrnk <0.01), 3.3 (3p22.2-3p14.1), 1.1 (1pter-1p36.22), 18.2 (18p11.23-18q12.2), 6.3 (6p21.1-6q15), 20.1 (20pter-20p12.3), and 18.1 (18pter-18p11.23). GSMA was performed with seven studies with linkage scores of LOD >1–1.85 for sensitivity test, confirming the linkage on chromosome 16p and 3p and revealing evidence of new linkage in bins 10.2 (10p14-10q11.21) and 22.2 (22q12.3-22pter). In conclusion, the meta-analysis of whole-genome linkage studies of BMD has shown chromosome 16pter-16p12.3 to have the greatest evidence of linkage as well as revealing evidence of linkage in chromosomes 1p, 3p, 6, 10, 18, 20p, and 22q across studies. This data may provide a basis with which to carry out targeted linkage and candidate gene studies particularly in these regions.     

Association of bone mineral density with postural stability and the fear of falling in Spanish postmenopausal women

Objective

The purpose of our study was to investigate the relationship between bone mineral density (BMD) and postural stability and the fear of falling in a 50- to 65-year-old postmenopausal population.

Study design

A cross-sectional, observational study was conducted on 118 postmenopausal women. According to their BMD values, participants were divided into two groups: BMD > −2.0 SD (n = 95) and ≤−2.0 SD (n = 23).

Main outcome measures

Postural stability, assessed with a resistive multi-sensor platform, fear of falling (FoF) and the history of falls in the last 12 months were investigated.

Results

Women with BMD ≤ −2.0 SD reported a significantly increased FoF when compared to women with BMD > −2.0 SD (P = 0.024, η² = 0.045, 1 − β = 0.624). In the postural stability analysis, the group with BMD ≤ − 2.0 SD showed, under the eyes-open condition, statistically significantly higher values for the velocity (VEO) (P = 0.040, η² = 0.037, 1 − β = 0.539) and the anteroposterior mean displacement of the center of pressure (YEO; P = 0.017, η² = 0.049, 1 − β = 0.669). No significant differences between groups were observed in the history of falls or in the rest of the stabilometric analyses.

Conclusions

In Spanish postmenopausal women under 65 years, a BMD ≤ −2.0 SD is significantly associated with postural instability (elevated VEO and XEO) and an increased FoF, which are two highly influential factors in the risk of falling.     

Serum Cathepsin K levels are not suitable to differentiate women with chronic bone disorders such as osteopenia and osteoporosis from healthy pre- and postmenopausal women

Objectives

Cathepsin K (CatK) is expressed in high levels in osteoplasts and therefore plays an important role in bone resorption. Thus CatK serum levels may be useful in the diagnosis of chronic bone disorders such as osteopenia and osteoporosis. Therefore we aimed at studying CatK levels in women putatively free of known skeletal disorders.

Study design

In total, 121 voluntary women, 27 premenopausal women aged between 20 and 45 years, and 94 postmenopausal women aged 59–81 years, all free of known skeletal disorders were included. All women underwent bone density measurement, routine labor parameter and measurement of serum CatK levels.

Main outcome measures

Based on WHO criteria, women were stratified in four groups (premenopausal: healthy; postmenopausal: healthy, osteopenia, osteoporosis), and their CatK levels were statistically analyzed.

Results

Using WHO criteria 21 postmenopausal women had normal bone mineral density (BMD), 49 had osteopenia and 24 had osteoporosis. All 27 premenopausal women had normal BMD. There were no significant differences in CatK between these groups. ROC analysis resulted in poor diagnostic validity of CatK, where the area under curve was 0.544. There was no correlation neither between CatK and other biomarkers as C-telopeptide crosslaps (CTX) or bone-specific alkaline phosphatase (BAP) nor between CatK and age.

Conclusions

Serum levels of CatK are not suitable to differentiate women with osteoporosis from healthy subjects.     

不同治疗方法对绝经后乳腺癌患者骨密度的影响

目的 探讨不同治疗方法 对绝经后乳腺癌患者骨密度(BMD)的影响.方法 研究分为健康对照组(50例)、肿瘤组[48例,其中24例再行他莫昔芬(TAM)组治疗].采用双能X线骨密度仪(DEXA)测定所有研究对象的基线BMD.肿瘤组术后均进行辅助化疗,其中24例(TAM组)化疗后继续使用TAM行内分泌治疗.用DEXA测量腰椎和左髋部位的BMD,比较肿瘤组化疗前、后以及TAM组行内分泌治疗8个月后BMD变化.结果 肿瘤组化疗后腰椎部位BMD(0.87±0.15)g/cm2比化疗前(0.93±0.15)g/cm2明显降低(P<0.05);TAM组行内分泌治疗8个月后腰椎BMD(0.90±0.04)g/cm2和股骨颈(0.74±0.05)g/cm2等左髋部位的BMD均有明显增加(P<0.05).结论 化疗可能导致绝经后乳腺癌患者BMD的下降,而TAM治疗能缓解化疗引起的BMD降低.     

Difference in the effect of adiposity on bone density between pre- and postmenopausal women

Objectives: Elevated bone mineral density (BMD) in obese women is partially attributable to the higher circulating estrogen levels derived from extraglandular aromatization in adipose tissue. However, it remains unclear whether there is an effect of overall adiposity on BMD in both pre- and postmenopausal women. The difference in the effect of overall adiposity on BMD between pre- and postmenopausal women was investigated. Materials and methods: Subjects were 296 premenopausal women with regular menstruation and 233 postmenopausal women. Age, age at menarche, years since menopause (YSM, in postmenopausal women), weight, height, and body mass index were recorded. Total fat mass amount, lean mass amount, and percentage of body fat were measured by whole body scanning with dual-energy X-ray absorptiometry (DEXA). Lumbar spine BMD (L2–L4) was measured by DEXA. In each group, significant determinants of BMD were investigated using univariate and stepwise multiple regression analysis. Results: In postmenopausal women, YSM, lean mass amount, total fat mass amount, and height were significant determinants of BMD (R²=0.273, P<0.001). In premenopausal women, only two variables including lean mass amount and age at menarche were significant determinants of lumbar spine BMD (R²=0.110, P<0.001), but total fat mass amount and percentage of body fat were not significant determinants of BMD. Conclusion: The effect of overall adiposity on BMD is more prominent in postmenopausal women than in premenopausal women.     

Spine and total body bone mineral density and serum testosterone levels in male athletes

Summary The aim of this study was to compare the effects of intense endurance vs strengthening exercise on bone mass and serum testosterone levels in male athletes. Bone mineral density (BMD) of the total body and spine and serum testosterone levels were measured in male rowers (n=12), triathletes (n=8) and sedentary controls (n=13). The total body scan also gave values for percentage body fat and regional bone densities. Calcium intake and physical activity levels were measured by questionnaire. The rowers had significantly higher BMD in the spine and total body than the triathletes (P < 0.01 and P < 0.05 respectively) and sedentary controls (P < 0.01 and P < 0.05). There were no differences between the triathletes and controls. Serum testosterone levels were significantly lower in the triathletes than in the controls (P < 0.05); there was no significant difference between the rowers and controls. All groups fell within the normal range for testosterone. In a step-wise multiple regression, including age, body mass, height, calcium intake and activity, no single factor had a significant effect on spine BMD. Body mass had a significant effect on total body BMD and could account for the differences between the groups. A significant positive correlation was found between calcium intake and total body BMD. The heavy weight training typical of rowing training seemed to result in significant bone accretion. The low testosterone levels in the triathletes may have negated any positive effect of the increased exercise on BMD.     

数字化摄影与双能X线吸收法在骨密度测定中的相关性研究

目的 探讨数字化摄影技术(DR)用于骨密度测定的方法和可行性.方法 门诊健康体检成年女性194例,DR拍摄标准骨盆平片,利用DR的图像后处理工作站选取股骨颈3点,Ward三角1点,股骨大粗隆3点,测量像素密度后求平均值.按年龄分层,观察DR像素密度变化规律;与双能X线吸收法(DXA)测定的相应部位骨密度值进行相关性分析.结果 不同年龄层成年女性DR像素密度不同,DR像素密度和DXA骨密度均随年龄增长呈逐渐下降趋势;左右侧股骨颈DR像素密度和DXA骨密度呈正相关(r=0.353,0.371)(均P＜0.01);左右侧Ward三角部位DR像素密度和DXA骨密度呈正相关(r=0.460,0.466)(均P＜0.01);左右大粗隆部位DR像素密度和DXA骨密度呈正相关(r=0.484,0.433)(均P＜0.01).结论 DR技术可用于髋部骨密度测定.