Relationships Among Bone Mineral Density,Body Composition,and Isokinetic Strength in Young Women

The purpose of this study was to examine the relationships among bone mineral density (BMD), body composition, and isokinetic strength in young women. Subjects were 76 women (age: 20 ± 2 yr, height: 164 ± 6 cm, weight: 57 ± 6 kg, body fat: 27 ± 4%) with a normal body mass index (18–25 kg/m²). Total body, nondominant proximal femur, and nondominant distal forearm BMD were measured with dual-energy x-ray absorptiometry. Isokinetic concentric (CON) and eccentric (ECC) strength of the nondominant thigh and upper arm were measured at 60 deg/sec. Fat-free mass (FFM) correlated (P < 0.001) with BMD of the total body (r = 0.56) and femoral neck (r = 0.52), whereas fat mass (FM) did not relate to BMD at any site. Leg FFM, but not FM, correlated with BMD in all regions of interest at the proximal femur. Weak associations were observed between arm FFM and forearm BMD. Isokinetic strength did not relate to BMD at any site after correcting for regional FFM. In conclusion, strong, independent associations exist between BMD and FFM, but not FM or isokinetic strength, in young women.     

Peripheral Bone Mineral Density and Different Intensities of Physical Activity in Children 6–8 Years Old: The Copenhagen School Child Intervention Study

This study aimed to evaluate the association between objectively measured habitual physical activity and calcaneal and forearm bone mineral density (BMD, g/cm²), one mechanically more loaded and one less loaded skeletal region, in children aged 6–8 years. BMD was measured in 297 boys and 265 girls by peripheral dual-energy X-ray absorptiometry in the forearm and calcaneus. An accelerometer registered the level of physical activity during 4 days (2 weekdays and the weekend). Weight, height, and skinfold thickness were measured. In order to establish thresholds (count · min⁻¹) for bone-stimulating physical activity, we evaluated different definitions of vigorous physical activity. The boys had 3.2% higher distal forearm bone mineral content (BMC, P < 0.001) and 4.5% higher distal forearm BMD (P < 0.001) than the girls. They also carried out 9.7% more daily physical activity and spent 14.6–19.0% more time in vigorous physical activity (all P < 0.05) compared to the girls. In contrast, the girls had 3.8% higher calcaneal BMC (P < 0.01) and 2.5% higher calcaneal BMD (P < 0.05) than the boys. Both calcaneal and forearm BMD were significantly related to total time of daily physical activity as well as with intense physical activity above all the chosen cut-off points (all P < 0.05). The β value for mean count · min⁻¹ physical activity was significantly lower than that for all the chosen cut-off points of vigorous activity both for calcaneal and distal forearm BMD. This study suggests that both habitual daily physical activity and amount of vigorous physical activity in children aged 6–8 years are associated with appendicular BMD.     

Ultrasound and X-ray-Based Bone Densitometry in Patients with Anorexia Nervosa

In 20 patients (mean age 23 ± 5 years) with anorexia nervosa (AN), bone mass was evaluated by broadband ultrasound attenuation (BUA) of the calcaneus, peripheral quantitative computed tomography (pQCT) of the distal radius, and dual X-ray absorptiometry (DXA) of the lumbar spine and the hip. Compared with 20 age- and sex- matched healthy controls, patients with AN showed marked osteopenia at all measuring sites. Values of BUA (33.0 ± 9dB/MHz vs. 51.0 ± 5.7 dB/MHz; P < 0.0001) and of BMD of all regions of the hip (e.g., femoral neck: 0.71 ± 0.13 g/cm² versus 0.89 ± 0.07 g/cm²; P < 0.001), lumbar spine (0.82 ± 0.15 g/cm² versus 1.24 ± 0.06 g/cm²; P < 0.003) and total BMD of the peripheral radius (303.2 ± 75 g/cm³ versus 369.4 ± 53.2 g/cm³, P < 0.001) were significantly reduced. Calculating a Z-score we found the most prominent differences between AN and controls by BUA of the calcaneus (−3.2 ± 1.6), followed by DXA at the lumbar spine (−2.9 ± 2.2) and the hip (femoral neck −2.1 ± 1.7) and by pQCT at the distal radius (total BMD −1.2 ± 2.0). There were highly significant correlations between BUA of the calcaneus and BMD of the femoral neck (r = 0.78, P < 0.0001) and lumbar spine (r = 0.75, P < 0.0001) as well as between BMD values of the femoral neck and lumbar spine (r = 0.95; P < 0.0001). In addition, there were significant correlations (P < 0.001) between body mass index (BMI) and the three different measuring sites and between the duration of the disease and BUA (r = 0.5, P < 0.05). Our data suggest that BUA of the calcaneus is a valuable tool in the management of osteoporosis. Being a fast, radiation-free investigation method of good acceptance, it may be well suited for an assessment of the skeletal status in patients with AN. Received: 14 October 1998 / Accepted: 10 December 1999     

Lifestyle Determinants of Bone Mineral: A Comparison Between Prepubertal Asian- and Caucasian-Canadian Boys and Girls

The purpose of this study was to examine the difference in lifestyle and morphometric factors that affect bone mineral and the attainment of peak bone mass in 168 healthy Asian (n = 58) and Caucasian (n = 110) Canadian, prepubertal girls and boys (mean age 8.9 ± 0.7) living in close geographical proximity. DXA (Hologic 4500) scans of the proximal femur (with regions), lumbar spine, and total body (TB) were acquired. We report areal bone mineral densities (aBMD g/cm²) at all sites and estimated volumetric density (νBMD, g/cm³) at the femoral neck. Dietary calcium, physical activity, and maturity were estimated by questionnaire. Of these prepubertal children, all of the boys and 89% of the girls were Tanner stage 1. A 2 × 2 ANOVA demonstrated no difference between ethnicities for height, weight, body fat, or bone mineral free lean mass. Asian children consumed significantly less dietary calcium (35%) on average and were significantly less active (15%) than their Caucasian counterparts (P < 0.001). There were significant ethnicity main effects for femoral neck bone mineral content (BMC) and αBMD (both P < 0.001) and significant sex by ethnicity interactions (P < 0.01). The Asian boys had significantly lower femoral neck BMC (11%), aBMD (8%), and νBMD (4.4%). At the femoral neck, BMFL mass, sex, and physical activity explained 37% of the total variance in aBMD (P < 0.05). In summary, this study demonstrated differences in modifiable lifestyle factors and femoral neck bone mineral between Asian and Caucasian boys. Received: 21 July 1998 / Accepted: 30 September 1999     

Influence of Physical Activity on Ultrasound and Dual-Energy X-ray Absorptiometry Bone Measurements in Peripubertal Girls: A Cross-Sectional Study

The aim of this cross-sectional study was to investigate whether two types of physical exercise affect the growing skeleton differently. We used calcaneal quantitative ultrasound measurements (QUS) and dual-energy X-ray absorptiometry (DXA) for measurement of bone mineral density (BMD), and to test how QUS values reflect the axial DXA values in these various study groups. A total of 184 peripubertal Caucasian girls aged 11–17 years (65 gymnasts, 63 runners, and 56 nonathletic controls) were studied. Weight, height, stage of puberty, years of training, and the amount of leisure-time physical activity were recorded. Broadband ultrasound attenuation (BUA) and sound of speed (SOS) through the calcaneus were measured. The BMD of the femoral neck and the lumbar spine were measured by DXA. The differences in mean values of bone measurements among each exercise group were more evident in pubertal than prepubertal girls. The mean BUA and SOS values of the pubertal gymnasts were 13.7% (77.8 dB/MHz versus 68.4 dB/MHz, P < 0.05) and 2.2% (1607.7 m/s versus 1572.4 m/s, P < 0.001) higher than of the controls, respectively. The mean BMD of the femoral neck in the pubertal gymnasts and runners was 20% (0.989 g/cm² versus 0.824 g/cm², P < 0.001) and 9.0% (0.901 g/cm² versus 0.824 g/cm², P < 0.05) higher than in the controls, respectively. The amount of physical activity correlated weakly but statistically significantly with all measured BMD and ultrasonographic values in the pubertal group (r = 0.19–0.35). The correlation between ultrasonographic parameters and BMD were weak, but significant among pubertal runners (r = 0.47–0.55) and controls (r = 0.39–0.42), whereas the DXA values of the femoral neck and the ultrasonographic parameters of the calcaneus did not correlate among highly physically active gymnasts. By stepwise regression analysis, physical activity accounted for much more of the variation in the DXA values than the ultrasonographic values. We conclude that the beneficial influence of exercise on bone status as measured by ultrasound and DXA was evident in these peripubertal girls. In highly active gymnasts the increase of the calcaneal ultrasonographic values did not reflect statistically significantly the BMD values of the femoral neck. Received: 28 June 1999 / Accepted: 2 November 1999     

A Pediatric Bone Mass Scan Has Poor Ability to Predict Adult Bone Mass: A 28-Year Prospective Study in 214 Children

As the correlation of bone mass from childhood to adulthood is unclear, we conducted a long-term prospective observational study to determine if a pediatric bone mass scan could predict adult bone mass. We measured cortical bone mineral content (BMC [g]), bone mineral density (BMD [g/cm²]), and bone width (cm) in the distal forearm by single photon absorptiometry in 120 boys and 94 girls with a mean age of 10 years (range 3–17) and mean 28 years (range 25–29) later. We calculated individual and age-specific bone mass Z scores, using the control cohort included at baseline as reference, and evaluated correlations between the two measurements with Pearson’s correlation coefficient. Individual Z scores were also stratified in quartiles to register movements between quartiles from growth to adulthood. BMD Z scores in childhood and adulthood correlated in both boys (r = 0.35, p < 0.0001) and girls (r = 0.50, p < 0.0001) and in both children ≥10 years at baseline (boys r = 0.43 and girls r = 0.58, both p < 0.0001) and children <10 years at baseline (boys r = 0.26 and girls r = 0.40, both p < 0.05). Of the children in the lowest quartile of BMD, 58 % had left the lowest quartile in adulthood. A pediatric bone scan with a value in the lowest quartile had a sensitivity of 48 % (95 % confidence interval [CI] 27–69 %) and a specificity of 76 % (95 % CI 66–84 %) to identify individuals who would remain in the lowest quartile also in adulthood. Childhood forearm BMD explained 12 % of the variance in adult BMD in men and 25 % in women. A pediatric distal forearm BMD scan has poor ability to predict adult bone mass.     

Bone mineral density in girls and boys at different pubertal stages: relation with gonadal steroids, bone formation markers, and growth parameters

Puberty has a key role in bone development. During puberty, several nutritional and hormonal factors play a major role in this process. The aim of this study was to determine the changes in areal bone mineral density (BMD), gonadal steroids, bone formation markers, and growth parameters in healthy Turkish pubertal girls and boys at different pubertal stages. In additional, we aimed to detect the relationship between BMD, sex steroids, and growth parameters, and to reveal the most important determinant of BMD in the pubertal period. BMD of the lumbar spine and total body was performed by dual-energy X-ray absorptiometry (Lunar DPX series) in 174 healthy pubertal children (91 girls, 83 boys), aged 11–15 years. Height and weight were measured. Pubertal stages were assesed. Bone formation markers and gonadal steroids were measured. BMD values significantly increased until stage IV in girls. In boys, BMD values also increased during puberty (P < 0.05), but it was significantly higher in stage IV compared with that in other pubertal stages (P < 0.01). Testosterone levels increased until stage IV in both sexes, particularly in boys. Estrogen levels significantly increased during puberty in girls, whereas it was significantly higher at stage IV in boys (P < 0.001). Bone-specific alkaline phosphatase (BAP) level was higher in early and midpuberty, and decreased in late puberty in girls (P < 0.001). BAP level was higher in stage IV in boys. Osteocalcin level was shown not to change significantly in pubertal stages. There was a modest correlation between BMD values and estrogen and testosterone levels in boys. In girls, there was a correlation between BMD values and estrogen levels only (P < 0.05). Weight was significantly associated with BMD in both sexes (P < 0.05). Estrogen had a significant influence on BMD in boys and girls. In conclusion, bone mass increased throughout puberty in both sexes. Peak bone mass was not achieved in girls, but was obtained at stage IV in boys. Bone formation markers were good predictors of bone mass in girls, but not in boys. Estrogen level made the greatest contribution to bone mineral acquisition in boys and girls. The achievement of peak bone mass was sustained by estrogen in boys. The major independent determinant of BMD in both sexes was weight.     

Contribution of Fat-Free Mass and Fat Mass to Bone Mineral Density Among Reproductive-Aged Women of White,Black, and Hispanic Race/Ethnicity

The objective of the study was to evaluate the contribution of fat-free mass (FFM) and fat mass (FM) to bone mineral density (BMD) and bone mineral apparent density (BMAD) among reproductive-aged women. Dual-energy X-ray absorptiometry scans were performed on 708 healthy black, white, and Hispanic women, 16–33 yr of age. The independent effect of FFM and FM on BMD and BMAD and the interaction of body composition measurements with race/ethnicity and age, were evaluated. FFM correlated more strongly than FM with BMD at the lumbar spine (r = 0.52 vs r = 0.39, p < 0.01) and the femoral neck (r = 0.54 vs r = 0.41, p < 0.01). There was a significant positive association between bone density measures [ln(BMD) and ln(BMAD)] and both ln(FFM) and ln(FM). The association of FFM with spinal BMD was stronger in 16–24-yr-old women than in 25–33-yr-old women (p < 0.006). The effect of FFM on femoral neck BMD was greater in blacks (p < 0.043) than Hispanics, whereas the effect of FM on spinal BMD was less (p < 0.047). Both FM and FFM are important contributors to bone density although the balance of importance is slightly different between BMD and BMAD.     

Bone Loss from the Hand in Women Following Distal Forearm Fracture

Bone loss occurs after distal forearm fracture, but it is unclear if this bone loss is fully recovered. We designed a cross-sectional study to evaluate the time course of the bone loss from the hand after distal forearm fracture. We identified 40 women who had a fracture of the distal forearm within the previous 4.5 years. Their ages ranged from 42 to 81 (mean 64 years) and time since fracture 6 to 54 (mean 28 months). These were compared with 95 women (mean age 67, range 57 to 80 years) from a population-based cohort. Lumbar spine (LS) and hand bone mineral density (BMD) were measured in all subjects using a Hologic QDR 1000/W densitometer. Ultrasound of the fingers of both hands was measured in the forearm fracture group using a DBM Sonic 1200 R model. Compared to controls, LS BMD was decreased by 6.4% (p<0.001), non-fractured hand by 3.2% (p<0.001) and the fractured hand by 6.1% (p<0.001) in the forearm fracture group. The mean differernce in bone density between the fractured and non-fractured hand was 0.0207 g/cm², the average value for the non-fractured hand being 0.304 g/cm². The decement in hand BMD was equivalent to 6.2% (p<0.0001). The difference in hand BMD between the fractured and non-fractured side was greatest when the time since fracture was short; there was no further difference in hand BMD after 2 years. Ultrasound showed a mean difference of 18.7 m/s in amplitude-dependent speed of sound (AD-SoS) with the average value being 1893 m/s. A 1.0% decrease was observed in the fractured hand AD-SoS (p<0.05). A strong relationship was observed between AD-SoS and BMD in both hands (r= 0.70, p<0.001). We conclude that distal forearm fracture results in a significant decrease in hand BMD that is partially reversible. The decrease in hand BMD is reflected in the ultrasound properties of the finger phalanx. Received: 26 July 2000 / Accepted: 5 January 2001     

Calcaneal Ultrasound Imaging in Healthy Children and Adolescents: Relation of the Ultrasound Parameters BUA and SOS to Age, Body Weight, Height, Foot Dimensions and Pubertal Stage

We investigated the quantitative ultrasound (QUS) parameters broadband ultrasound attenuation (BUA) and speed of sound (SOS) measured in the posterior part of the calcaneus at the region of interest (ROI) with the lowest attenuation, using an ultrasound imaging device (UBIS 3000) in 491 healthy Caucasian children and adolescents (262 girls, 229 boys) between 6 and 21 years old. The relation of age, body weight, height, foot dimensions and pubertal stage to BUA and SOS was assessed. BUA increased nonlinearly with age in boys and girls, r ² being 0.44 (p<0.001) and 0.57 (p<0.001), respectively. SOS increased linearly with age in girls (r ²= 0.04, p<0.001). There was no significant increase in SOS in boys (r ²= 0.01, p>0.05). Heel width was significantly correlated with BUA (r= 0.20, p<0.005 in boys; r= 0.27, p<0.05 in girls) and with SOS (r=−0.19, p<0.005 in boys; r=−0.08, p<0.05 in girls). After downward adjustment of the ROI size according to foot length quartiles, significantly lower BUA and SOS values were found compared with those with the standard ROI size of 14 mm. After correction for heel width and adjustment of the ROI size based on foot length, BUA and SOS were significantly associated with age in boys (r ²= 0.36, p<0.001 and 0.06, p<0.05) and in girls (r ²= 0.53 and 0.06, both p<0.001). Tanner stage was significantly correlated with BUA (r= 0.62, p<0.001 in boys; r= 0.73, p<0.001 in girls) but not with SOS. BUA but not SOS increased significantly with the number of years since menarche (p<0.001). In a multiple stepwise regression analysis in boys, age, weight and foot length were independent predictors for BUA, and age and foot length for SOS. In girls, age and weight were independent predictors for BUA and age was the only independent predictor for SOS. After correction for age, pubertal stages and heel width were no longer determinants for QUS parameters in either boys or girls. In conclusion, BUA increased significantly with age in both sexes. SOS increased with age in both boys and girls, but the increase was small and not statistically significant in boys. SOS, as measured with the UBIS 3000 device, may therefore not be appropriate to assess skeletal status in healthy children. Whether SOS and BUA are affected in children with skeletal disorders has yet to be determined. In boys, age, weight and foot length were independent predictors for BUA and age and foot length for SOS. In girls, age and weight were independent predictors for BUA and age was the only independent predictor for SOS. In our opinion, children with small feet should be measured with a smaller ROI diameter than those with larger feet. Received: 28 October 1999 / Accepted: 19 June 2000     

Correlation between fat mass and blood pressure in healthy children

Obesity is a well-known risk factor for arterial hypertension. The aim of this study was to analyze which surrogate marker of adiposity, i.e., body mass index (BMI) or fat mass (FM), as measured by bioimpedance analysis (BIA), best correlated with blood pressure in healthy children. Body weight, height, and casual blood pressure (BP) were measured in 193 healthy children (103 boys), aged 8–16 years. Body composition was determined by BIA. The correlation between BMI and age was linear, whereas the correlation between percentage of FM and age was nonlinear and it was different in boys and girls. Blood pressure standard deviation scores (SDS) correlated with FM SDS (BIA) over the entire normal range (systolic: r = 0.26, p = 0.002; diastolic: r = 0.33, p < 0.01). An evaluation of the children based on BP (three groups: BP < 50th percentile, 50th < BP > 95th percentile; BP > 95th percentile) revealed that hypertensive children had a higher BMI (17.6 vs. 19.4 vs. 26.2 kg/m², respectively) and a greater FM (14.0 vs. 16.8 vs. 30.2%, respectively). In conclusion, the divergence in FM in healthy boys and girls can be determined by BIA but not by BMI. In healthy children, BP within the entire normal range correlated with FM, children with established hypertension presented with a significantly higher FM. The study points to FM as an important determinant of BP pressure in obese and non-obese children.     

Relative contribution of lean and fat mass component to bone mineral density in males

 We investigated the relative contribution of lean body mass (LBM) and body fat mass to bone mineral density (BMD) in 93 healthy Japanese male volunteers (mean age, 33.1 ± 6.9 years; range, 18–54 years). Age, height (Ht), weight (Wt), and body mass index (BMI, Wt/Ht²) were recorded. Body fat mass, percentage of body fat, body fat mass/Ht², LBM, LBM/Wt, LBM/Ht², and lumbar spine (L2–L4) and total body BMD (TBBMD) were measured by dual-energy X-ray absorptiometry. On the Pearson correlation test, LBM was positively correlated with L2–L4 BMD. LBM, LBM/Wt, and LBM/Ht² were positively correlated with TBBMD. However, body fat mass and body fat mass/Ht² were not correlated with lumbar spine and total body BMD. On the partial correlation test, LBM was still correlated with lumbar spine (r = 0.307, P < 0.05) and total body BMD (r = 0.545, P < 0.0001), irrespective of age and height, whereas body fat mass was not correlated with BMD of these sites (r = −0.069 and −0.169, respectively). We concluded that, in males, LBM is one of the significant determinants of BMD whereas body fat mass is a negligible BMD determinant. Received: February 15, 2002 / Accepted: July 5, 2002 Offprint requests to: T. Douchi     

Precision and Accuracy of Computed Digital Absorptiometry for Assessment of Bone Density of the Hand

Widespread osteoporosis testing and diagnosis are currently limited due to the high capital cost and reduced portability of many existing bone densitometry techniques. In this study we evaluated an inexpensive, low radiation, X-ray-based technique for assessing bone density of the middle phalanx. The technique, termed computed digital absorptiometry (CDA), is similar to radiographic absorptiometry (RA), using a single-energy X-ray source, an aluminum alloy step-wedge, and a charge-coupled device (CCD) detector system to automatically compute bone mineral content (BMC, g) and bone mineral density (BMD, g/cm²) in the middle phalanx of the third finger. The potential advantage of CDA over current RA techniques is that by using a filmless detector system, no off-site processing of radiographs is required and bone density results are obtained immediately after the test. Using human cadaveric specimens we determined the accuracy and short-term precision of CDA as well as its correlation with other hand and forearm bone densitometry methods. We obtained 26 cadaveric forearms (50% female, mean age 78 years, range 52–96 years). BMC and BMD of the middle phalanx of the third finger were determined using CDA and using RA. We assessed forearm BMC and BMD using single-energy and dual-energy X-ray absorptiometry (SXA and DXA). Precision of CDA was assessed by measuring ten of the specimens five times each with repositioning between measurements. Finally, the middle phalanx was dissected and incinerated to determine ash weight. BMC estimates from CDA and from RA were strongly correlated with ash weight (r = 0.89, p < 0.001 and r = 0.93, p < 0.001, respectively). The mean coefficients of variation using CDA were 1.36% and 0.70% for phalanx BMC and BMD, respectively. BMC and BMD measured by CDA were strongly correlated with hand and forearm bone mineral measurements performed by SXA, DXA and TA (r = 0.74–0.91). These results indicate that CDA accurately and precisely predicts BMC of the middle phalanx. Thus, with further clinical verification, this technique may prove to be a useful tool for the wide-spread testing and assessment of osteoporotic fracture risk.     

A 3-Year Physical Activity Intervention Program Increases the Gain in Bone Mineral and Bone Width in Prepubertal Girls but not Boys: The Prospective Copenhagen School Child Interventions Study (CoSCIS)

The aim of this study was to evaluate the effect of increasing the amount of time spent in physical education classes on bone mineral accrual and gain in bone size in prepubertal Danish children. A total of 135 boys and 108 girls, aged 6–8 years, were included in a school-based curriculum intervention program where the usual time spent in physical education classes was doubled to four classes (180 min) per week. The control group comprised age-matched children (62 boys and 76 girls) recruited from a separate community who completed the usual Danish school curriculum of physical activity (90 min/week). Dual-energy X-ray absorptiometry was used to evaluate bone mineral content (BMC; g), bone mineral density (g/cm²), and bone width at the calcaneus and distal forearm before and after 3 years of intervention. Anthropometrics and Tanner stages were evaluated on the same occasions. General physical activity was measured with an accelerometer worn for 4 days. In girls, the intervention group had a 12.5% increase (P = 0.04) in distal forearm BMC and a 13.2% increase (P = 0.005) in distal forearm scanned area compared with girls in the control group. No differences were found between the intervention and control groups in boys. Increasing the frequency of physical education classes for prepubertal children is associated with a higher accrual of bone mineral and higher gain in bone size after 3 years in girls but not in boys.     

Effects of Cigarette-Smoking on Bone Mass as Assessed by Dual-Energy X-ray Absorptiometry and Ultrasound

In order to elucidate the influence of nicotine smoking on bone mass in elderly women, bone mass was cross-sectionally assessed by dual energy X-ray absorptiometry (DXA) in total body, hip and lumbar spine, as well as with ultrasound of calcaneus and phalanges of the hand. Subjects were 1,042, 75-year old women, recruited on a population basis (Osteoporosis Prospective Risk Assessment (OPRA) study). We found bone mineral density (BMD) to be lower in hip (0.71 vs. 0.76 g/cm², p<0.0001 for femoral neck) and total body (0.96 vs. 1.02 g/cm², p<0.0001) in current smokers compared to never-smokers. There was no difference in BMD of the lumbar spine between current smokers and never-smokers. Bone mass as assessed by ultrasound of the calcaneus was lower for speed of sound (p<0.01), broadband ultrasound attenuation (p<0.0001) and stiffness (p<0.0001) in current smokers than in never-smokers. No differences were found for ultrasound measurements of the phalanges between smokers and never-smokers. Also, weight and current physical activity as assessed by a questionnaire differed significantly between current smokers and never-smokers.  There was no evident difference between former smokers and never-smokers in any of the skeletal regions assessed by DXA or ultrasound.  After correcting for differences in weight and physical activity, current smokers had lower BMD in all hip sites (p<0.05) and total body (p<0.01) compared to never-smokers. Ultrasound and BMD spine did not differ between these two groups after correction for weight and physical activity.  We conclude that nicotine smoking has a negative influence on bone mass independent of differences in weight and physical activity. This difference is detected by DXA but not by ultrasound measurements of the calcaneus or the phalanges. The present data are encouraging since no bone mass differences were found between former and never-smokers. Received: 29 March 2002 / Accepted: 2 July 2002     

The influence of ghrelin, adiponectin, and leptin on bone mineral density in healthy postmenopausal women

The association of body fat mass (FM) with bone mineral mass (BMC) and bone mineral density (BMD) has been attributed to a mechanical load exerted on the skeleton by FM and by the effect of different hormones. The aim of the present study was to determine whether there is a relationship between ghrelin, adiponectin, and leptin with BMC and BMD in healthy postmenopausal women (n = 88; age, 68.9 ± 6.8 years; body mass index, 27.4 ± 3.6 kg/m²). Body composition, BMC, and BMD were derived by dualenergy X-ray absorptiometry. Waist-to-hip (WHR) and waist-to-thigh (WTR) ratios were also obtained. Ghrelin was associated with total BMC (β = −0.945; P = 0.0001), total BMD (β = −0.959; P = 0.0001), lumbar spine BMD (β = −0.945; P = 0.0001), and femoral neck BMD (β = −0.957; P = 0.0001), and remained associated (P < 0.041) in different analyses that controlled for measured body composition and hormonal and insulin resistance values. However, the associations between ghrelin and measured bone mineral values were no longer significant (P > 0.149) when adjusted for body fat distribution values (WHR, WTR). Adiponectin was significantly related to total BMC (β = −0.931; P = 0.0001), total BMD (β = −0.940; P = 0.0001), lumbar spine BMD (β = −0.937; P = 0.0001), and femoral neck BMD (β = −0.940; P = 0.0001) values, and these relationships remained significant (P < 0.019) after adjusting for measured body fat, hormonal, and insulin resistance values but not when adjusted for fat-free mass (FFM; P > 0.106). In addition, significant associations of leptin with total BMC (β = 0.912; P = 0.0001), total BMD (β = 0.907; P = 0.0001), lumbar spine BMD (β = 0.899; P = 0.0001), and femoral neck BMD (β = 0.906; P = 0.0001) were found. These associations remained significant (P < 0.010) in different analyses that controlled for hormonal and insulin resistance values, but the associations between leptin and bone mineral values were no longer significant (P > 0.145) when adjusted for specific body composition values (WHR, WTR, FM, and FFM). In conclusion, it appears that the influence of plasma ghrelin, adiponectin, and leptin levels on BMC and BMD values is mediated or confounded by the specific body composition parameters in healthy postmenopausal women.     

Bone mineral density in weight lifters

Summary The effect of intense physical training on the bone mineral content (BMC) and soft tissue composition, and the development of these values after cessation of the active career, was studied in 40 nationally or internationally ranked male weight lifters. Nineteen were active and 21 had retired from competition sports. Fifty-two age- and sexmatched nonweight lifters served as controls. The bone mineral density (BMD) in total body, spine, hip, and proximal tibial metaphysis was measured with a Lunar Dual-energy X-ray absorptiometry (DXA) apparatus and the BMD of the distal forearm was measured with single photon absorptiometry (SPA). Seventeen of the lifters had been measured earlier with SPA in the forearm and 23 in the tibial condyle during their active career in 1975. The BMD was significantly higher in the weight lifters compared with the controls (10% in the total body P<0.001, 12% in the trochanteric region P<0.001, and 13% in the lumbar spine P<0.001). All measured regions except the head showed significant higher bone mass in the weight lifters compared with the controls. In older lifters, the difference from the controls seemed to increase in total body and lumbar vertebrae (BMD), but remained unchanged in the hip. Significant correlation was found between the SPA measurements in 1975 and the corresponding measurements 15 years later in both the forearm (r=0.51, P<0.05 at the 1-cm level and r=0.87, P<0.001 at the 6-cm level) and in the tibial condyle (r=0.61, P<0.01). There was no difference in BMD for any region between active and retired weight lifters that was not explained by difference in age. The weight lifters were on average 5 cm shorter but of the same weight as the controls. In the weight lifters, the body mass index (BMI) was increased as was the lean body mass, but not the fat content.     

SULT1E1 Genetic Polymorphisms Modified the Association between Phytoestrogen Consumption and Bone Mineral Density in Healthy Korean Women

Sulfotransferase 1E1 (SULT1E1) catalyze estrogen into sulfate conjugation and is involved in the metabolism of phytoestrogen. A community-based cross-sectional study was conducted on 397 Korean women, to evaluate the association between genetic polymorphisms of SULT1E1 and bone mineral density (BMD) and the combined effect of the genetic polymorphism and phytoestrogen intake for BMD in Korean women. BMDs of the distal radius and the calcaneus were measured by dual-energy X-ray absorptiometry. Genotypes of SULT1E1 IVS1-447 C>A, IVS4-1653 T>C, and *959 G>A were determined by the 5′-nuclease assay (TaqMan). Phytoestrogen intake was estimated by a food-frequency questionnaire validated against multiple 24-hour recalls. Women with the SULT1E1 *959 GG genotype had a 4.5% lower BMD at the distal radius (P _trend = 0.05) and a 7.9% lower BMD at the calcaneus compared to those with AA genotype (P _trend < 0.01), whereas the SULT1E1 IVS1-447 CC genotype and IVS4-1653 TT genotype were not associated with BMD. There was no significant trend of BMD with the numbers of CTG-containing haplotypes, but calcaneal BMDs significantly differed between SULT1E1 CTA-CTA haplotype and CTG-CCA haplotype (P < 0.05). When stratified by SULT1E1 genotype, the correlation between phytoestrogen consumption and BMD at the calcaneus was noteworthy in women with SULT1E1 *959 GG genotype (r = 0.25, P = 0.01) or SULT1E1 IVS 4-1653 TT genotype (r = 0.15, P = 0.02). This trend remained significant only in postmenopausal women (r = 0.36, P = 0.01) after multiple testing was corrected by the false discovery rate method. In conclusion, the genetic polymorphism of SULT1E1 *959 G > A was associated with BMD at the distal radius and calcaneus, and the association between phytoestrogen consumption and calcaneal BMD might be modified by this genetic polymorphism.     

Ultrasound and densitometry of the calcaneus correlate with the failure loads of cadaveric femurs

We assessed the bone mineral density (BMD) of 16 matched sets of cadaveric proximal femurs and feet using dual-energy x-ray absorptiometry (DXA). We also estimated the femoral neck length from the DXA scans. Quantitative ultrasound densitometry was used to measure the velocity of sound and broadband ultrasound attenuation (BUA) in the calcaneus of each foot. The proximal femurs were then tested to failure in a loading configuration designed to simulate a fall with impact to the greater trochanter. Femoral neck BMD and trochanteric BMD were strongly associated with the femoral failure load (r²=0.79 and 0.81, respectively; P<0.001), whereas femoral neck length was modestly correlated with femoral failure load (r²=0.27, P=0.04). Calcaneal BMD (r²=0.63, P<0.001) and BUA (r²=0.51, P=0.002) were also significantly associated with femoral failure load. Given the small sample size, we were unable to detect differences in the strength of the correlations between the independent parameters and femoral failure load. Using linear multiple regression analyses, the strongest predictor of femoral failure load was a combination of femoral neck BMD and femoral neck length (R²=0.85, P<0.001). Thus, it appears that both femoral and calcaneal bone mineral properties may be useful for identifying those persons at greatest risk for hip fracture.     

Forearm bone mineral density in patients with rheumatoid arthritis

 The aims of the present study were to determine whether patients with rheumatoid arthritis (RA) show significantly lower forearm bone mineral density (BMD) than sex- and age-matched healthy controls, and to identify significant factors that are associated with their BMD loss. One hundred eighty-four patients with RA and 185 sex- and age-matched healthy controls were enrolled in the study: 71 men 37–68 years of age (RA, 31; controls, 40), 129 premenopausal women 30–48 years of age (RA, 67; controls, 62), and 169 postmenopausal women 48–69 years of age (RA, 86; controls, 83). The correlation of forearm BMD, measured by dual energy X-ray absorptiometry with anatomic grade in the wrist, functional class, duration of disease, steroid use, modified health assessment questionnaire (HAQ) score for the upper and lower extremities, levels of serum C-reactive protein and rheumatoid factor, erythrocyte sedimentation rate, and years since menopause (YSM) were examined by multiple regression analysis. In men with RA, no clinical factors were significantly correlated with forearm BMD, and the BMD did not differ significantly from that in controls (0.329 ± 0.060 [mean ± SD] vs. 0.351 ± 0.069 g/cm²). In premenopausal women with RA, the HAQ score for the upper extremities was positively correlated with forearm BMD (P < 0.05), but the BMD did not differ significantly from that in controls (0.298 ± 0.085 vs. 0.324 ± 0.088 g/cm²); in postmenopausal women with RA, YSM and anatomic grade in the wrist were negatively correlated with forearm BMD (P < 0.01 and P < 0.05), and the BMD was significantly lower than in controls (0.192 ± 0.063 vs. 0.223 ± 0.076 g/cm², P < 0.01). These findings suggest that forearm BMD loss in patients with RA may be accelerated in women after menopause, and that YSM and disuse of the wrist may be significant determinants of their forearm BMD loss. Received: February 18, 2002/ Accepted: May 23, 2002