Umbilical venous IGF-1 concentration, neonatal bone mass, and body composition.

IGF-1 is a key growth factor during fetal life. Using DXA, we found that the concentration of IGF-1 in umbilical cord serum is strongly related to neonatal whole body bone mineral content, lean mass, and fat mass. However IGF-1 did not explain the relationships of maternal smoking, fat mass, and physical activity with neonatal bone mass. The study supports a direct role for circulating IGF-1 in growth of the fetal skeleton. INTRODUCTION: Evidence is accumulating that the risk of osteoporosis in later life may be determined in part by environmental influences during intrauterine and early postnatal life. We previously reported that maternal birthweight, smoking, fat stores, and physical activity during pregnancy predict neonatal bone mass. While the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis is an important determinant of postnatal skeletal growth, there are few data relating the concentration of growth factors in umbilical cord blood to bone mineral content (BMC) and other indices of body composition in the newborn infant. MATERIALS AND METHODS: We conducted a population-based study in a cohort of full-term, newborn infants whose mothers were characterized for lifestyle, body composition, and nutrition through their normal pregnancies. In a sample of 119 infants from the cohort, we related cord serum IGF-1 and insulin-like growth factor binding protein (IGFBP)-3 concentrations to neonatal body composition measured by DXA and evaluated the extent to which this cytokine mediates the previously reported effects of maternal diet and lifestyle on neonatal bone mass. RESULTS: There were strong positive associations between cord serum IGF-1 concentration and whole body BMC (r = 0.38, p < 0.001), whole body lean mass (r = 0.40, p < 0.001), and whole body fat mass (r = 0.50, p < 0.001) after adjusting for gestational age and sex. There was no association between cord serum IGF-1 and BMC adjusted for bone size. Neither cord serum IGF-1 nor IGFBP-3 explained the relationships that we previously reported between maternal influences and neonatal bone mass. CONCLUSIONS: Cord serum IGF-1 is more closely related to the size of the neonatal skeleton than to its degree of mineralization. Documented maternal determinants of neonatal bone mass seem to mediate their effects independently of variations in cord serum IGF-1 in healthy pregnancies.     

Changes in bone mineral density and body composition during pregnancy and postpartum. A controlled cohort study

Summary  

In a controlled cohort study, bone mineral density (BMD) was measured in 153 women pre-pregnancy; during pregnancy; and 0.5, 4, 9, and 19 months postpartum. Seventy-five age-matched controls, without pregnancy plans, were followed in parallel. Pregnancy and breastfeeding cause a reversible bone loss, which, initially, is most pronounced at trabecular sites but also involves cortical sites during prolonged breastfeeding.     

Comparisons of body size, composition, and whole body bone mass between North American and South African children.

We compared whole body BMC of 811 black, white, and mixed ancestral origin children from Detroit, MI; Johannesburg, South Africa; and Cape Town, South Africa. Our findings support the role of genetic and environmental influences in the determination of bone mass in prepubertal children. INTRODUCTION: Higher bone mass and lower fracture rates have been shown in black compared with white children and adults in North America. MATERIALS AND METHODS: We compared whole body BMC (WBBMC), whole body fat mass (WBFM), and whole body fat free soft tissue (WBFFST) data between three ethnic groups of children from Detroit, MI (n = 181 white, USW; n = 230 black, USB), Johannesburg, South Africa (n = 73 white, SAW; n = 263 black, SAB), and Cape Town, South Africa (n = 64 mixed ancestral origin, SAM). RESULTS: SAB and SAW groups were slightly older than USW and USB groups (9.5 +/- 0.3 versus 9.3 +/- 0.1 yr); however, USB and USW boys were significantly taller, were heavier, and had a higher BMI than SAM and SAB boys. USB girls were significantly taller than SAB girls and heavier than SAB and SAM girls. In South Africa and the United States, black children had a significantly higher WBBMC than white children, after adjusting for selected best predictors. After adjusting for age, weight, and height, WBBMC was significantly higher in the SAB and SAW boys than in USW and USB and in the SAM group compared with the USW and USB groups. WBFFST and WBFM made significant contributions to a best linear model for log(WBBMC), together with age, height, and ethnicity. The best model accounted for 79% of the WBBMC variance. When included separately in the model, the model containing WBFFST accounted for 76%, and the model containing WBFM accounted for 70%, of the variance in WBBMC. CONCLUSIONS: WBBMC is lower in children of European ancestry compared with African ancestry, irrespective of geographical location; however, South African children have significantly higher WBBMC compared with USB and USW groups, thereby acknowledging the possible contribution of environmental factors. Reasons for the significantly higher WBBMC in the children of mixed ancestral origin compared with the other groups need to be studied further.     

Cigarette smoking, obesity, and bone mass

This study was designed to assess the effects of smoking on bone mass and bone loss and to ascertain whether these effects are independent of effects on adiposity and hormone concentrations. A total of 84 healthy, peri- and postmenopausal women were studied prospectively over 3 1/2 years. Heavy smokers had significantly (p less than 0.05) lower radial and vertebral bone mineral content than light or nonsmokers (who did not differ from each other). In regression models, which contained measurements of obesity, pack-years smoking remained a significant predictor of bone mass. However, there were no detectable effects of smoking on rates of bone loss at any site. Smokers appear to be at greater risk of osteoporosis due to their lower bone mass. However, this reduced bone mass is already present around the time of menopause, and rates of bone loss during this period do not appear to be influenced by smoking. Furthermore, we have previously shown in this population that menopausal serum estrogen concentrations (which determine rates of bone loss) do not differ between the smokers and nonsmokers. Further studies of larger groups are required to determine whether small differences in bone loss may exist, since the power to detect such differences was not ideal in this study.     

Fetal heart assessment in the first trimester of pregnancy: influence of crown-rump length and maternal body mass index

Objective

To evaluate the influence of the crown-rump length and body mass index on sonographic evaluation of the fetal heart using abdominal and vaginal routes in the first trimester of pregnancy.

Methods

We conducted a cross-sectional study with 57 pregnant women between 12-14 weeks (CRL≤ 84 mm). We evaluated the following fetal cardiac plans using the abdominal and vaginal routes: four-chamber view, right ventricle outflow tract, left ventricle outflow tract and aortic arch. We used the B-mode, color Doppler and four-dimensional ultrasonography (spatio-temporal image correlation). To evaluate the influence of crown-rump length and body mass index in the assessment of fetal cardiac planes, we used the t test unpaired.

Results

There were no statistically significant differences in the rates of success and failure between abdominal and vaginal routes in relation to body mass index, however, there was a higher failure rate in vaginal assessment using B mode associated with color Doppler (P<0.01).

Conclusion

The crown-rump length and body mass index had no interference in fetal cardiac assessment in the first trimester of pregnancy.     

Whole body bone mass and body composition in a girl with achondroplasia, at ages 9 through 12.

A 9-yr-old white female with achondroplasia was one of a group of 773 children who were recruited for a study of the accumulation of whole body skeletal mass during four annual measurements. Measurements of bone, fat, and lean mass were obtained with a Hologic 1000W instrument. The following variables are used to compare the subject with the 130 healthy white girls who participated in the study: bone mineral content (BMC), bone mineral density (BMD), and bone mineral apparent density (BMAD). Ratios of BMC to weight or BMC to height, and BMD to weight or height, were also calculated. We found that the BMC of the subject was lower when compared to the reference group, but the ratios of BMC to weight or BMC to height were similar in both. BMD was also lower in the patient, but, when expressed in relation to height and weight, the ratios were similar or slightly higher in the case. BMAD was higher in the subject with achondroplasia at all ages. The subject had a lower percentage fat and higher percentage lean mass than the reference children. We conclude that the accumulation of bone mass in this subject with achondroplasia is appropriate for her reduced body size.     

男性青少年身体成分与骨矿含量的关系

为了解青少年身体成分中瘦体重和体脂含量究竟那种成分对骨矿含量影响起主要作用，我们对５８名男性青少年（年龄１７．２±０．７岁，范围：１５．５—１８．７岁）进行人体测量，计算出瘦体重和体脂含量，用ＢＨ－６０１２型二维扫描单光子骨密度仪测量非优势侧桡骨中远１／３处及桡骨超远端骨矿含量（ＢＭＣ，ｇ）、骨宽（ＢＷ，ｃｍ）、骨密度（ＢＭＤ，ｇ／ｃｍ２），为消除身高的影响分别计算桡骨中远１／３处和桡骨超远端ＢＭＤ／身高值（ＢＭＤ／Ｈ，ｇ／ｃｍ３）。以桡骨中远１／３处及桡骨超远端的ＢＭＣ、ＢＭＤ、ＢＭＤ／Ｈ作因变量，年龄、身高、瘦体重、体脂含量作自变量进行多元线性回归分析，结果表明瘦体重和体脂含量均与骨矿含量有关（Ｐ＜０．０５），但经骨形态即骨宽较正的骨密度及身高校正的ＢＭＤ／Ｈ仅与瘦体重有关（Ｐ＜０．０５），因此说明男性青少年身体成分中瘦体重对桡骨超远端骨密度的影响作用较大。     

绝经后女性体质量指数、体成分与骨密度的变化特征及关系

目的 探讨绝经后女性年龄、体质量指数（body mass index, BMI）及体成分的变化特征及与骨质疏松症之间的关系。方法 选取广州中医药大学第三附属医院2019年12月–2021年1月门诊收集的98名绝经后女性的体成分及骨密度资料,根据受试者的年龄和BMI分组,比较各年龄组及各BMI组的体成分差别,通过Spearman分析年龄、BMI及体成分对骨质疏松情况的影响,利用多元线性回归研究整体骨密度和整体骨矿含量的影响因素。结果 各个年龄组的整体骨密度（P＜0.001）及整体骨矿含量（P＜0.05）随年龄增加而下降,而各个BMI组的整体骨矿含量（P＜0.05）、整体肌肉质量（P＜0.001）、整体脂肪质量（P＜0.001）随BMI增加而增加。Spearman相关分析显示,随着年龄增加（P=0.005,r=0.281）,骨质疏松程度越严重;而随着BMI（P=0.019,r= – 0.237）、整体骨矿含量（P＜0.001,r= – 0.719）、肌肉质量（P=0.014,r= – 0.249）和脂肪质量（P=0.013,r= – 0.249）的增加,患骨质疏松的程度越轻。多元线性回归分析结果显示,年龄与绝经后女性整体骨密度（P=0.002,B= – 0.004）及整体骨矿含量呈负相关（P=0.000,B= – 0.013）;而整体肌肉质量（P=0.018,B=0.022）和整体脂肪质量（P=0.037,B=0.027）则与绝经后女性整体骨矿含量呈正相关。结论 年龄是绝经后女性患骨质疏松症的危险因素,而BMI、肌肉质量和脂肪质量是保护因素,有助于提高整体骨密度和整体骨矿含量。     

High-intensity exercise in female athletes: effects on bone mass and body composition

Abstract We investigated bone mass and body composition in young healthy athletic women in order to determine the influence of high-impact physical activity on bone, fat and lean mass. In a case-control study, we studied 68 healthy women, aged 18–45 years, divided in two groups (age and body mass index matched): 39 sedentary women and 29 professional karate athletes. Family and medical histories and information on habits and dietary patterns were collected through a self-administered questionnaire. Bone mineral density (BMD, g/cm²) of whole body, lumbar spine and proximal femur was measured by means of dual energy X-ray absorptiometry (Hologic QDR 4500A scanner; Hologic,Waltham, USA; version 8.26). Total and subregional fat and lean whole body masses were also measured (grams). Significantly higher femoral and total body bone masses were found in active women compared to sedentary women (total femur: 1.00±0.09 vs. 0.95±0.10 g/cm², p<0.05; femoral neck: 0.94±0.11 vs. 0.87±0.11, p<0.05; trochanter: 0.77±0.10 vs. 0.70±0.08, p=0.002; intertrochanter: 1.17±0.09 vs. 1.11±0.12, p<0.05; total body: 1.19±0.06 vs. 1.14±0.08, p<0.05). Active women also had lower fat mass (total: 16510±4430 vs. 20736±7883 g, p=0.007; limbs: 9952±2779 vs. 11888±4147, p=0.027; trunk: 5807±1970 vs. 8325±4113 p=0.001) and higher limb lean mass (15574±2124 vs. 14532±2034 g, p=0.05). A significantly lower calcium intake was registered in active women. Oral contraceptive use appeared to significantly increase femoral bone density. Physical activity increased bone mass in young active women, and this effect seemed to be superior to that of dietary calcium intake.     

Influence of soft tissue body composition on bone mass and metabolism

Total body bone mineral (TBBM), lean body mass (LBM), and fat mass (FM) were measured by dual photon ¹⁵³Gd absorptiometry in four female groups: (a) 27 patients with hip fracture, (b) 40 patients with spinal crush fracture, (c) 17 patients with osteoarthrosis, and (d) 26 healthy postmenopausal women. TBBM was significantly decreased in the two osteoporotic groups. The FM tended to be smaller in the two osteoporotic groups and larger in the osteoarthrotic group compared to the control group, whereas, LBM was virtually equal in all four groups. A significant negative correlation (p < 0.01) was found between fasting urinary calcium corrected for creatinine and FM, whereas no relation between plasma bone Gla protein and FM could be demonstrated. We conclude that an increased fat mass after the menopause decreases bone resorption without a corresponding decrease in bone formation.     

Genetic influence on bone phenotypes and body composition: a Swedish twin study

Bone mineral density (BMD), bone size and bone turnover are independent determinants of fractures in elderly. Earlier twin studies of these phenotypes have revealed high heritability for BMD and bone area, and more moderate heritability for bone turnover markers. No previous Scandinavian study has evaluated the genetic and environmental contribution to the variance of these phenotypes, despite the fact that Scandinavian countries have the highest incidence of osteoporotic fractures worldwide. Participants were selected from the Swedish Twin Registry. All intact like-sexed twin pairs born in 1965 or earlier and living in the county of Uppsala were invited to participate. A total of 102 twin pairs (45 monozygotic and 57 dizygotic) accepted the invitation to participate. All twins underwent measurement of BMD and bone area using dual-energy X-ray absorptiometry. Hip geometry was also calculated. Markers for bone formation (osteocalcin) and bone resorption (CrossLaps) were measured in serum. We observed a substantial heritability for BMD at the lumbar spine (0.85; 95 % CI 0.54–0.90), the femoral neck (0.75; 95 % CI 0.62–0.83), and the proximal femur (0.84; 95 % CI 0.74–0.90). The values for bone area were approximately similar to those for BMD. Bone turnover markers had a slightly lower genetic influence with a value of 0.69 (0.53–0.80) for osteocalcin and 0.58 (95 % CI 0.33–0.75) for CrossLaps. As a comparison, the heritabilities of body height and weight were 0.95 and 0.82, respectively. The high heritability on bone phenotypes among Swedish middle-aged and older men and women should encourage further work on the identification of specific genetic pathways. Continuing research in this area could reveal the mechanisms behind the strong genetic susceptibility of bone-related phenotypes.     

Effect of kidney transplantation on bone mass and body composition in males

BACKGROUND: Bone loss is a frequent and well-known complication in the first months after renal transplantation, but there are no data considering body composition variables (bone, fat, and lean mass) together in transplant recipients. This prospective study investigated total body bone density, fat mass, and lean mass before and 1, 2, 3, 4, and 6 months after renal transplantation in male patients who underwent hemodialysis. METHODS: Twenty consecutive renal transplant male patients aged 23-64 years (mean, 40 years; median, 41 years) received one of two immunosuppressive therapies (cyclosporine+methylprednisolone, or cyclosporine+methylprednisolone+azathioprine). The bone, fat, and lean mass of the total body and its related subregions were assessed by means of dual X-ray photon absorptiometry. Mixed factorial analysis of variance for repeated measurements was used for the statistical analysis. RESULTS: During the 6 months after transplantation, there was a reduction in trabecular bone mass in the spine, ribs, and pelvis total body subregions; the reduction was statistically significant in the last two subregions. There was no statistically significant difference in the lean mass of the total body or its subregions over time, but there was a statistically significant increase in the fat mass of the total body and all of its subregions; the increase in total and trunk fat mass seemed to be greater in the patients not receiving azathioprine. CONCLUSIONS: Up to 6 months after renal transplantation in male patients who underwent hemodialysis, there is a marked increase in fat mass, a significant loss of trabecular bone mass, and no change in cortical bone and lean mass.     

Relative importance of body composition, osteoporosis-related behaviors, and parental income on bone speed of sound in adolescent females

Introduction  

Adolescence provides a unique opportunity to employ strategies aimed at optimizing peak bone mass yet there are limited studies on the relationship between specific social constructs, osteoporosis-related behaviors, and bone health status in adolescent females. The purpose of this study was to examine associations between bone speed of sound (SOS) and body composition, osteoporosis-related health behaviors, and parental income in adolescent females.     

中年妇女年龄、月经状态、体重指数及体力活动对机体组成及脂肪分布的影响

目的 研究中年妇女年龄、月经状态、体重指数(body mass index,BMI)及体力活动对机体组成及脂肪分布的影响. 方法 横断面收集于北京协和医院体检中心体检的健康妇女,利用经过效度和信度检验的国际体力活动问卷短卷中文版调查研究对象的体力活动情况,利用双能X线吸收法(DEXA)测定机体组成及脂肪分布情况. 结果 共收集到162例妇女资料,年龄40～62岁、(52.81±5.31)岁.多元线性回归分析结果显示,全身脂肪组织百分比与BMI(标准化偏回归系数b=0.70)、月经状态(b=0.19,生育期赋值1,绝经过渡期赋值2,绝经后赋值3,下同)呈正相关,而与体力活动能量消耗呈负相关(b=-0.17),回归方程的决定系数R2-0.55.全身无脂肪组织含量(fat-free tissue)与BMI呈正相关(b=0.61)、与月经状态呈负相关(b=-0.14),回归方程的决定系数R2=0.39.躯干脂肪/全身脂肪比值与BMI(b=0.32)、月经状态(b=0.30)呈正相关,回归方程的决定系数R2=0.20.校正了BMI、月经状态及体力活动的影响后,年龄与全身脂肪组织百分比、全身无脂肪组织含量、躯干脂肪/全身脂肪比值均无明显相关性. 结论 月经状态对机体组成及脂肪分布具有独立影响,随着生殖衰老的进展,脂肪组织增加且趋于中心性分布,机体无脂肪组织含量降低.而年龄本身与机体组成及脂肪分布无直接关系.中年妇女应增加体力活动,保持适当的体重以降低绝经对脂肪组织所造成的不利变化.     

Associations between maternal peak bone mass and bone mass in prepubertal male and female children.

The aim of this study was to estimate heritability of bone density in premenopausal women, prepubertal male, and prepubertal female child pairs. We studied 291 pairs (mothers, mean age, 33 years, range 22-45 years; children, mean age, 7.92 years, range 7.32-8.92 years). Bone density and body composition were assessed by dual-energy X-ray absorptiometry. Height and weight were measured in both mother and child. Body size-adjusted heritability estimates for areal bone density (g/cm2) were all statistically significant (femoral neck, 59%; lumbar spine, 38%; total body, 41%) and were consistently and significantly higher in mother-daughter pairs (n = 105) as compared with mother-son pairs (n = 186). Heritability estimates for bone mineral apparent density (BMAD; g/cm3) were marginally lower but remained statistically significant at all sites (femoral neck, 51%; lumbar spine, 32%; total body, 38%). Maternal osteopenia was associated with significant reductions in bone mass at all sites in the children (femoral neck, 0.75 SD and p < 0.0001; lumbar spine, 0.61 SD and p < 0.0001; total body, 0.43 SD and p = 0.012). Mother-child bone areal bone density correlation coefficients and prediction of low bone mass in the child were greater (but this did not reach statistical significance) if the corresponding anatomical site in the mother was used for prediction with the exception of the total body. These data confirm that heritability of bone mass extends to prepubertal children and is gender- and possibly site-specific as well as under separate genetic control to growth. Furthermore, the strength of the mother-child association is such that bone density screening of mothers would make it possible to identify most prepubertal children at higher risk of osteoporosis in later life.     

A cross-sectional study of smoking and bone mineral density in premenopausal parous women: effect of body mass index, breastfeeding, and sports participation.

The objective of this cross-sectional study was to describe the relationship between cigarette smoking, effect modifiers, and bone density in premenopausal parous women. We studied a sample of 276 women (mean age 33 years) from Southern Tasmania. The study factors were cigarette smoking, body mass index (BMI), sports participation, and breastfeeding history. Bone mineral density was measured utilizing an Hologic QDR 2000 densitometer and converted to Z scores using the group mean and variance. There were 118 current smokers and 158 nonsmokers. Smokers had lower bone mass at all sites (femoral neck, -0.32 SD, 95% confidence interval [CI] -0.60 to -0. 04; lumbar spine, -0.49 SD, 95% CI -0.76 to -0.22; total body, -0.40 SD, 95% CI -0.66 to -0.14). Stratifying by BMI revealed that this association was only present, but greater in magnitude, for those with a BMI <25 kg/m2. Smokers who had breastfed at least one child had an additional deficit in bone mass (femoral neck, -0.48 SD, 95% CI -0.89 to -0.07; lumbar spine, -0.39 SD, 95% CI -0.80 to 0.02; total body, -0.37 SD, 95% CI -0.77 to 0.06) while smokers who took part in competitive sport had significant increments in bone mass (femoral neck, 0.74 SD, 95% CI 0.31 to 1.17; lumbar spine, 0.48 SD, 95% CI 0.03 to 0.93; total body, 0.42 SD, 95% CI 0.00 to 0.84). Neither of these two associations were present in nonsmokers. In conclusion, current smoking was associated with substantial deficits in bone mass in our sample of women, particularly those with a BMI <25 kg/m2. In addition, smoking may prevent the usual postweaning recovery phase of bone after breastfeeding while sports participation may offset the negative effect of smoking on bone mass. These observations need to be confirmed in longitudinal studies but they imply that past studies of smoking in this age group may have missed important associations as they did not consider possible effect modifiers.     

Bone mass and body composition in normal women.

The interrelationships between measurements of bone mass and total-body bone mineral were examined in a cross-sectional study of normal healthy women aged 17-82 years. In addition we evaluated the relationship between measures of body composition, estimated by four independent techniques, and bone mass in the same population. Considering the group as a whole, bone mass at all sites correlated with each other and with total-body bone mineral (TBBM). Cancellous and cortical sites could predict TBBM equally well. As expected, all measurements of bone mass were significantly lower in postmenopausal women in comparison to premenopausal women. Declines in bone mass were only seen in premenopausal women in the femoral neck and Ward's triangle, not in lumbar spine, radius, or skeleton as a whole. In postmenopausal women bone mass correlated negatively with age and years from menopause equally at all sites. TBBM was significantly related to height and weight in both premenopausal and postmenopausal women. In premenopausal and postmenopausal women TBBM also correlated with fat mass, but TBBM was much better correlated with percentage body fat in premenopausal than postmenopausal women. TBBM was a constant proportion of lean body mass in premenopausal women, but the fraction of lean mass occupied by the skeleton declined with age in postmenopausal women. Correction of TBBM for lean mass did not change the relationship between TBBM and percentage fat in premenopausal women but eliminated the relationship in postmenopausal women. Regional measurements, which are at least partially corrected for body size by dividing mass by area, correlated less well with height and weight and with any index of obesity, especially in postmenopausal women.