Bone mineral density and broadband ultrasound attenuation with estrogen treatment of postmenopausal women.

The purpose of the current study was to determine the changes in lumbar spine, hip, and calcaneus bone mineral density (BMD), and in calcaneus broadband ultrasound attenuation (BUA) in early menopausal women and to assess the effects of estrogen replacement therapy (ERT) on bone mass at these sites over a 2-yr period. Fifty-three Caucasian women who were at least 6 mo postmenopausal were divided into two groups based on estrogen use. Twenty-one women, average age 53.0 +/- 0.6 yr and 2.9 +/- 0.3 yr since menopause, had been receiving estrogen in combination with progesterone for at least 6 mo prior to enrollment in the study. Thirty-two women, average age 52.7 +/- 0.8 yr and 2.8 +/- 0.3 yr since menopause, had never received ERT. During the 2-yr study, women not receiving ERT had significant decreases in BMD of the spine -2.3 +/- 0.6%, femoral neck -2.2 +/- 0.8%, and calcaneus -4.7 +/- 0.9%, and in BUA of the calcaneus -14.3 +/- 1.8%. ERT prevented the decreases in BMD at the spine +0.4 +/- 0.6% and calcaneus -2.3 +/- 1.1%, but did not prevent a significant decrease in bone mass at the femoral neck -1.9 +/- 0.8% and BUA at the calcaneus -17.8 +/- 3.2%. Neither group had significant decreases in total hip BMD. This study demonstrates again that ERT prevents the menopause-associated decreases in spine BMD. However, in this group of women, ERT did not prevent loss in femoral neck BMD or BUA. The results suggest that women being treated with estrogen for maintenance of BMD in early menopause need to be monitored to ensure efficacy of therapy, especially in the maintenance of femoral neck BMD.     

Calcium Plus Vitamin D Supplementation Has Limited Effects on Femoral Geometric Strength in Older Postmenopausal Women: The Women��s Health Initiative

Calcium plus vitamin D (CaD) supplementation has a modest but significant effect on slowing loss of femoral bone mass and reducing risk of hip fractures in adherent postmenopausal women. The goal of this study was to determine if CaD supplementation influences hip structural parameters that are associated with fracture risk. We studied 1,970 postmenopausal women enrolled in the Women??s Health Initiative randomized controlled trial of CaD at one of three bone mineral density (BMD) clinical centers. Hip structural analysis software measured BMD and strength parameters on DXA scans at three regions: femoral narrow neck, intertrochanter, and shaft. Random effects models were used to test the average differences in hip BMD and geometry between intervention and placebo. There was greater preservation of hip BMD at the narrow neck with CaD relative to placebo across 6?years of intervention. CaD also altered the underlying cross-sectional geometry at the narrow neck in the direction of greater strength, with small increases in cross-sectional area and section modulus and a decrease in buckling ratio with CaD relative to placebo. While trends at both the intertrochanter and shaft regions were similar to those noted at the narrow neck, no significant intervention effects were evident. There was no significant interaction of CaD and age or baseline calcium levels for hip structural properties. CaD supplementation is associated with modest beneficial effects on hip structural features at the narrow neck, which may explain some of the benefit of CaD in reducing hip fracture risk.     

Risk factors for longitudinal bone loss in elderly men and women: the Framingham Osteoporosis Study.

Few studies have evaluated risk factors for bone loss in elderly women and men. Thus, we examined risk factors for 4-year longitudinal change in bone mineral density (BMD) at the hip, radius, and spine in elders. Eight hundred elderly women and men from the population-based Framingham Osteoporosis Study had BMD assessed in 1988-1989 and again in 1992-1993. BMD was measured at femoral neck, trochanter, Ward's area, radial shaft, ultradistal radius, and lumbar spine using Lunar densitometers. We examined the relation of the following factors at baseline to percent BMD loss: age, weight, change in weight, height, smoking, caffeine, alcohol use, physical activity, serum 25-OH vitamin D, calcium intake, and current estrogen replacement in women. Multivariate regression analyses were conducted with simultaneous adjustment for all variables. Mean age at baseline was 74 years +/-4.5 years (range, 67-90 years). Average 4-year BMD loss for women (range, 3.4-4.8%) was greater than the loss for men (range, 0.2-3.6%) at all sites; however, BMD fell with age in both elderly women and elderly men. For women, lower baseline weight, weight loss in interim, and greater alcohol use were associated with BMD loss. Women who gained weight during the interim gained BMD or had little change in BMD. For women, current estrogen users had less bone loss than nonusers; at the femoral neck, nonusers lost up to 2.7% more BMD. For men, lower baseline weight and weight loss also were associated with BMD loss. Men who smoked cigarettes at baseline lost more BMD at the trochanter site. Surprisingly, bone loss was not affected by caffeine, physical activity, serum 25-OH vitamin D, or calcium intake. Risk factors consistently associated with bone loss in elders include female sex, thinness, and weight loss, while weight gain appears to protect against bone loss for both men and women. This population-based study suggests that current estrogen use may help to maintain bone in women, whereas current smoking was associated with bone loss in men. Even in the elderly years, potentially modifiable risk factors, such as weight, estrogen use, and cigarette smoking are important components of bone health.     

军事训练对青年男性军人股骨近端几何结构的影响

目的通过比较军人与非军人青年男性骨密度和髋关节几何结构的异同,探讨运动对处于骨量缓慢增长期的青年男性骨密度及骨力学结构的影响。方法回顾性纳入符合研究条件的60名青年男性军人和60名普通青年男性作为受试者。采用美国HOLOGIC双能X线骨密度仪(Dual energy X-ray absorptiometry,DXA)对受试者的腰椎和左髋关节骨密度进行检测,在分析骨密度的同时,利用髋关节结构分析(Hip strength analysis,HSA)软件在DXA扫描图像基础上得出股骨近端几何力学参数。结果军人组腰椎总体BMD、股骨颈BMD较普通青年对照组分别增加2.97%和6.45%,但两组腰椎骨密度差异无统计学意义(P0.05),两组间股骨颈骨密度差异有统计学意义(P0.05);股骨颈几何力学参数比较结果显示:军人组FNCSA、FN-CT大于普通青年对照组(P0.05),而FN-BR明显低于普通青年对照组(P0.01),差异均有统计学意义,两组CSMI、SM相关参数间差异均无统计学意义(P0.05)。结论运动可提高骨量缓慢增长期的骨密度值,同时可改善股骨颈近端骨几何结构,提高骨强度。即骨量增加与髋关节结构重塑同步,共同提高髋部骨强度。     

Retinol intake and bone mineral density in the elderly: the Rancho Bernardo Study.

Retinol is involved in bone remodeling, and excessive intake has been linked to bone demineralization, yet its role in osteoporosis has received little evaluation. We studied the associations of retinol intake with bone mineral density (BMD) and bone maintenance in an ambulatory community-dwelling cohort of 570 women and 388 men, aged 55-92 years at baseline. Regression analyses, adjusted for standard osteoporosis covariates, showed an inverse U-shaped association of retinol, assessed by food-frequency questionnaires in 1988-1992, with baseline BMD, BMD measured 4 years later, and BMD change. Supplemental retinol use, reported by 50% of women and 39% of men, was an effect modifier in women; the associations of log retinol with BMD and BMD change were negative for supplement users and positive for nonusers at the hip, femoral neck, and spine. At the femoral neck, for every unit increase in log retinol intake, supplement users had 0.02 g/cm2 (p = 0.02) lower BMD and 0.23% (p = 0.05) greater annual bone loss, and nonusers had 0.02 g/cm2 (p = 0.04) greater BMD and 0.22% (p = 0.19) greater bone retention. However, among supplement users, retinol from dietary and supplement sources had similar associations with BMD, suggesting total intake is more important than source. In both sexes, increasing retinol became negatively associated with skeletal health at intakes not far beyond the recommended daily allowance (RDA), intakes reached predominately by supplement users. This study suggests there is a delicate balance between ensuring that the elderly consume sufficient vitamin A and simultaneously cautioning against excessive retinol supplementation.     

Femur strength index predicts hip fracture independent of bone density and hip axis length

Introduction Proximal femoral bone strength is not only a function of femoral bone mineral density (BMD), but also a function of the spatial distribution of bone mass intrinsic in structural geometric properties such as diameter, area, length, and angle of the femoral neck. Recent advancements in bone density measurement include software that can automatically calculate a variety of femoral structural variables that may be related to hip fracture risk. The purpose of this study was to compare femoral bone density, structure, and strength assessments obtained from dual-energy X-ray absorbtiometry (DXA) measurements in a group of women with and without hip fracture. Methods DXA measurements of the proximal femur were obtained from 2,506 women 50 years of age or older, 365 with prior hip fracture and 2,141 controls. In addition to the conventional densitometry measurements, structural variables were determined using the Hip Strength Analysis program, including hip axis length (HAL), cross-sectional moment of inertia (CSMI), and the femur strength index (FSI) calculated as the ratio of estimated compressive yield strength of the femoral neck to the expected compressive stress of a fall on the greater trochanter. Results Femoral neck BMD was significantly lower and HAL significantly higher in the fracture group compared with controls. Mean CSMI was not significantly different between fracture patients and controls after adjustment for BMD and HAL. FSI, after adjustment for T score and HAL, was significantly lower in the fracture group, consistent with a reduced capacity to withstand a fall without fracturing a hip. Conclusion We conclude that BMD, HAL, and FSI are significant independent predictors of hip fracture.     

Proximal femur structural geometry changes during and following lactation

Human lactation is associated with transient decreases in bone mineral density (BMD). Bone strength is related to both mass and structural geometry. This study investigated longitudinal changes of hip bone strength during lactation using hip structural analysis (HSA), which determines hip structural geometry (including areal BMD, BMDa) from dual-energy X-ray absorptiometry scans (DXA). Forty-eight lactating women were studied longitudinally at the proximal femur using DXA at approximately 2 weeks postpartum, peak-lactation and post-lactation. Nonpregnant, nonlactating women (NPNL, n=23) were studied concurrently at baseline and after 1 year. Hip scans were analysed using HSA at the narrow neck, intertrochanter and proximal shaft. No significant change (>0.05) was observed in NPNL women for any measurement. In contrast, for lactating women BMDa decreased significantly from 2 weeks postpartum to peak-lactation at narrow neck (-2.8%), intertrochanter (-3.2%) and shaft (-1.4%). Cross-sectional area (CSA) decreased at narrow neck (-3.4%) and intertrochanter (-2.7%). There were no significant changes in bone width. Section modulus decreased at intertrochanter (-2.1%). At shaft, cortical thickness decreased (-1.7%) and buckling ratio increased (2.3%). By post-lactation, measurements were not significantly different from 2 weeks postpartum except for decrements in BMDa (-1.1%) and CSA (-1.2%) at the shaft. During the study, lactating women lost 5% of their body weight. Adjusting for weight changes decreased the magnitude and significance of HSA changes at peak-lactation and by post-lactation there were no significant differences from 2 weeks postpartum. Calcium intake was not a significant predictor of changes in HSA variables. In conclusion, lactation is associated with significant but transient changes in hip BMD and structural geometry. Changes in body weight but not calcium intake were associated with these changes. These small changes at the hip during lactation occurred mainly at internal surfaces and had minimal impact on bending or compressive strength.     

Femoral Bone Mineral Density, Neck-Shaft Angle and Mean Femoral Neck Width as Predictors of Hip Fracture in Men and Women

The effect of femoral bone mineral density (BMD) and several parameters of femoral neck geometry (hip axis length, neck–shaft angle and mean femoral neck width) on hip fracture risk in a Spanish population was assessed in a cross-sectional study. All parameters were determined by dual-energy X-ray absorptiometry. There were 411 patients (116 men, 295 women; aged 60–90 years) with hip fractures in whom measurements were taken in the contralateral hip. Controls were 545 persons (235 men, 310 women; aged 60–90 years) who participated in a previous study on BMD in a healthy Spanish population. Femoral neck BMD was significantly lower, and neck–shaft angle and mean femoral neck width significantly higher, in fracture cases than in controls. The logistic regression analysis adjusted by age, height and weight showed that a decrease of 1 standard deviation (SD) in femoral neck BMD was associated with an odds ratio of hip fracture of 4.52 [95% confidence interval (CI) 2.93 to 6.96] in men and 4.45 (95% CI 3.11 to 6.36) in women; an increase of 1 SD in neck–shaft angle of 2.45 (95% CI 1.73 to 3.45) in men and 3.48 (95% CI 2.61 to 4.65) in women; and an increase of 1 SD in mean femoral neck width of 2.15 (95% CI 1.55 to 2.98) in men and 2.40 (95% CI 1.79 to 3.22) in women. The use of a combination of femoral BMD and geometric parameters of the femoral neck except for hip axis length may improve hip fracture risk prediction allowing a better therapeutic strategy for hip fracture prevention. Received: 16 September 1999 / Accepted: 22 February 2000     

Association of Body Composition and Physical Activity with Proximal Femur Geometry in Middle-Aged and Elderly Afro-Caribbean Men:

Osteoporotic fractures are less prevalent in African Americans than in caucasians, possibly because of differences in bone structural strength. Bone structural adaptation can be attributed to changes in load, crudely measured as lean and fat mass throughout life. The purpose of this analysis was to describe the associations of leg lean mass, total body fat mass, and hours walked per week with femoral bone mineral density (BMD) and bone geometry in a cross-sectional sample of 1,748 men of African descent between the ages of 40 and 79 years. BMD, section modulus (Z), cross-sectional area (CSA), and subperiosteal width were measured from dual energy X-ray absortiometry (DXA) scans using the hip structural analysis (HSA) program. Multiple linear regression models explained 35% to 48% of the variance in bending (Z) and axial (CSA) strength at the femoral neck and shaft. Independent of all covariates including total body fat mass, one standard deviation increase in leg lean mass was significantly associated with a 5% to 8% higher Z, CSA, and BMD (P < 0.010) at the neck and shaft. The number of hours walked per week was not a strong or consistent independent predictor of bone geometry or BMD. We have shown that weight is the strongest independent predictor of femur BMD and geometric strength although the effect appears to be mediated by lean mass since leg lean mass fraction and total body fat mass fraction had significant and opposing effects at the narrow neck and shaft in this group of middle aged and elderly men.     

High parity is associated with increased bone size and strength

Some, but not all, studies report an association between decreased hip fracture risk and high parity despite similar bone mineral density (BMD). Our hypothesis was that bone size, a major determinant of bone strength, is greater in women with high parity compared with low parity or nulliparous women. A cross-sectional study of 168 Hutterite women aged 40–80 years was conducted. BMD, bone mineral content (BMC) and bone area of the total body (TB), hip, femoral neck (FN), and lumbar spine (LS) were measured, as well as bone geometry at the 4% and 20% distal radius and bending strength at 20% radius. Diet and activity recall and strength measurements were obtained. Of the 168 women, 42 (25%) were nulliparous while the remaining women reported 1 to 16 births (median=6). Of the 126 parous women, 122 (97%) breast-fed their infants (range 1.5–24 months). Hip, FN and LS BMD were not associated with either parity or months of breast-feeding. TB BMC and bone area (both, p <0.05) and FN bone area ( p <0.01) were associated with parity. FN bone area was 4% greater in women with 7+ vs 1–4 children. Torsional bending strength, which includes structural and material bone properties, at the 20% distal radius was greater with higher parity ( p =0.01). No bone measure was associated with average months of breast-feeding. High parity is associated with increased radial torsional bending strength and femoral neck size. The greater femoral neck size, without higher BMD, may explain the reduced hip fracture risk among women with high parity previously reported in some studies.     

Structural adaptation to changing skeletal load in the progression toward hip fragility: the study of osteoporotic fractures.

Longitudinal, dual-energy X-ray absorptiometry (DXA) hip data from 4187 mostly white, elderly women from the Study of Osteoporotic Fractures were studied with a structural analysis program. Cross-sectional geometry and bone mineral density (BMD) were measured in narrow regions across the femoral neck and proximal shaft We hypothesized that altered skeletal load should stimulate adaptive increases or decreases in the section modulus (bending strength index) and that dimensional details would provide insight into hip fragility. Weight change in the approximately 35 years between scan time points was used as the primary indicator of altered skeletal load. "Static" weight was defined as within 5% of baseline weight, whereas "gain" and 'loss" were those who gained or lost >5%, respectively. In addition, we used a frailty index to better identify those subjects undergoing changing in skeletal loading. Subjects were classified as frail if unable to rise from a chair five times without using arm support. Subjects who were both frail and lost weight (reduced loading) were compared with those who were not frail and either maintained weight (unchanged loading) or gained weight (increased loading). Sixty percent of subjects (n = 2,559) with unchanged loads lost BMD at the neck but not at the shaft, while section moduli increased slightly at both regions. Subjects with increasing load (n = 580) lost neck BMD but gained shaft BMD; section moduli increased markedly at both locations. Those with declining skeletal loads (n = 105) showed the greatest loss of BMD at both neck and shaft; loss at the neck was caused by both increased loss of bone mass and greater subperiosteal expansion; loss in shaft BMD decline was only caused by greater loss of bone mass. This group also showed significant declines in section modulus at both sites. These results support the contention that mechanical homeostasis in the hip is evident in section moduli but not in bone mass or density. The adaptive response to declining skeletal loads, with greater rates of subperiosteal expansion and cortical thinning, may increase fragility beyond that expected from the reduction in section modulus or bone mass alone.     

Cross-sectional geometry, bone strength, and bone mass in the proximal femur in black and white postmenopausal women.

Osteoporosis is characterized by both a low bone mass and a disruption of the architectural arrangement of bone tissue, leading to decreased skeletal strength and increased fracture risk. Although there are well-known ethnic differences in bone mass and fracture risk, little is known about possible ethnic differences in bone structure. Therefore, we studied cross-sectional geometry in the hip in a sample of postmenopausal black and white women in order to investigate ethnic differences that might contribute to differences in bone strength and ultimately hip fracture risk. We recruited 371 postmenopausal black and white women who were entering the Women's Health Initiative (WHI) clinical trials in Detroit. Bone density measurements of the proximal femur were done by dual-energy X-ray absorptiometry (DXA) using a Hologic 1000 Plus bone densitometer. The DXA data were used for hip structure analysis, which treats the entire proximal femur as a continuous curved beam from the proximal shaft to the femoral neck. This permits the analysis of cross-sectional geometric properties in two narrow regions corresponding to thin (5 mm) cross-sectional slabs seen on edge. The results indicate significant ethnic differences in bone density, cross-sectional geometry, and dimensional variables. Specifically, the black women have a significantly higher bone density in both locations (10.1% and 4.1% for the neck and shaft, respectively); greater cross-sectional geometric properties in the neck (ranging from 6.1% to 11.6%), but a smaller endocortical diameter in the neck (3.6%). There are fewer significant differences in cross-sectional geometry in the shaft location. Our data suggest that the spatial distribution of bone is arranged in the femoral neck to resist greater loading in black women compared with white women.     

Vitamin C supplement use and bone mineral density in postmenopausal women.

Vitamin C is known to stimulate procollagen, enhance collagen synthesis, and stimulate alkaline phosphatase activity, a marker for osteoblast formation. Studies of dietary vitamin C intake and the relation with bone mineral density (BMD) have been conflicting, probably because of the well-known limitations of dietary nutrient assessment questionnaires. The purpose of this study was to evaluate the independent relation of daily vitamin C supplement use with BMD in a population-based sample of postmenopausal women. Subjects were 994 women from a community-based cohort of whom 277 women were regular vitamin C supplement users. Vitamin C supplement use was validated. Daily vitamin C supplement intake ranged from 100 to 5,000 mg; the mean daily dose was 745 mg. Average duration of use was 12.4 years; 85% had taken vitamin C supplements for more than 3 years. BMD levels were measured at the ultradistal and midshaft radii, hip, and lumbar spine. After adjusting for age, body mass index (BMI), and total calcium intake, vitamin C users had BMD levels approximately 3% higher at the midshaft radius, femoral neck, and total hip (p < 0.05). In a fully adjusted model, significant differences remained at the femoral neck (p < 0.02) and marginal significance was observed at the total hip (p < 0.06). Women taking both estrogen and vitamin C had significantly higher BMD levels at all sites. Among current estrogen users, those also taking vitamin C had higher BMD levels at all sites, with marginal significance achieved at the ultradistal radius (p < 0.07), femoral neck (p < 0.07), and total hip (p < 0.09). Women who took vitamin C plus calcium and estrogen had the highest BMD at the femoral neck (p = 0.001), total hip (p = 0.05), ultradistal radius (p = 0.02), and lumbar spine. Vitamin C supplement use appears to have a beneficial effect on levels of BMD, especially among postmenopausal women using concurrent estrogen therapy and calcium supplements.     

Detrimental effect of oral contraceptives on parameters of bone mass and geometry in a cohort of 248 young women

The aim of this cross-sectional analysis was to examine the skeletal effects of low-dose monophasic oral contraceptive (OC) use in a cohort of 248 young Caucasian women aged 18-24 years. Areal bone mineral density (BMD) of the femoral neck and lumbar spine was evaluated by dual-energy X-ray absorptiometry. Volumetric BMD, bone mineral content (BMC), and bone geometry were assessed in the tibia by peripheral quantitative computed tomography (pQCT). The women were allocated into ever or never OC users, and also into 5 different OC groups according to duration and time of initiation of OC use. Women with >2 years of OC use and OC initiation within 3 years after menarche were characterized by 10% lower femoral neck areal BMD (P<0.001), 5% lower spine areal BMD (not significant, P=0.101), 7% lower distal tibial total BMC (P<0.05), and 6% lower total BMC at the tibial shaft (P<0.05) relative to never users. In addition, women who had ever used OCs had lower bone mass at the femoral neck and tibial shaft, despite similar age, height, weight, BMI, hours of exercise, and calcium intake compared with never users. At the tibial shaft, OC users showed reduced total cross-sectional area, and increased cortical BMD. In conclusion, our data suggest that OC use is associated with a detrimental effect on bone mass in young women, and provide further insight into the pathophysiological mechanisms involved.     

Effects of denosumab on the geometry of the proximal femur in postmenopausal women in comparison with alendronate.

Denosumab is a fully human monoclonal antibody against receptor activator of nuclear factor-kappaB ligand, an essential mediator of osteoclast activity and survival. In postmenopausal women with low bone mineral density (BMD), subcutaneous denosumab decreases bone resorption and increases BMD. This post hoc analysis reports on subjects treated for up to 24 months with denosumab 60mg 6 monthly (N=39), placebo (N=39), or open-label alendronate 70mg once weekly (N=38) in a phase 2 study. Hip scans were done by dual-energy X-ray absorptiometry at baseline, 12, and 24 months; these were analyzed with hip structural analysis software to evaluate BMD and cross-sectional geometry parameters at the narrowest segment of the femoral neck, the intertrochanter, and the proximal shaft. Geometric parameters and derived strength indices included bone cross-sectional area, section modulus, and buckling ratio. At 12 and 24 months denosumab and alendronate improved these parameters compared with placebo. Denosumab effects were greater than alendronate at the intertrochanteric and shaft sites. The magnitude and direction of the changes in structural geometry parameters observed in this study suggest that denosumab treatment may lead to improved bone mechanical properties. Ongoing phase 3 studies will determine whether denosumab reduces fracture risk.     

Bone cross-sectional geometry is not associated with atypical femoral fractures in Asian female chronic bisphosphonate users

IntroductionAtypical femoral fractures (AFF) tend to occur in Asian women with prolonged bisphosphonate exposure. Hip geometry is thought to contribute to the risk of AFF formation. We examined the hip structural geometry parameters in Asian female chronic bisphosphonate users who sustained an AFF and compared them to chronic bisphosphonate users who did not sustain any femoral fracture (NFF) and bisphosphonate-naïve patients who sustained an osteoporotic femoral fracture (OFF).Materials & methodsThirty-one patients with AFFs were gender and age-matched to 31 patients with NFFs and 49 patients with OFFs. The Hip Structural Analysis parameters analyzed were bone mineral density (BMD), cross-sectional area (CSA; a metric of resistance to axial compression), section modulus (SM; a metric of resistance to tensile loads), average cortical thickness (ACT; mean thickness of the femoral cortices), buckling ratio (BR; an index of likelihood of local buckling), and neck shaft angle (NSA; the angle between the neck and shaft axes). The regions analyzed were three cross-sections measured at the narrowest femoral neck diameter, the intertrochanteric area, and the proximal femoral shaft. One-way ANOVA with Bonferroni adjustment for multiple comparisons was used to compare parameters between the three patient groups, with statistical significance defined as p < 0.05.ResultsThere were no statistical differences in parameters between patients with AFFs and patients with NFFs at all measured regions. Patients with AFFs and NFFs had statistically higher BMD, CSA, ACT, SM values and lower BR values at the NN and IT regions than patients with OFFs. Additionally, patients with NFFs had statistically higher SM values at the IT region than patients with OFFs, while patients with AFFs had statistically higher BMD, CSA, and ACT values at the FS region. All other measured parameters were not statistically different between the groups.ConclusionsChronic bisphosphonate users with and without AFFs had similar femoral structural geometries. Unlike in other populations, varus neck shaft angles were not found to be associated with AFFs in Asian female chronic bisphosphonate users. Thus, bone cross-sectional geometry is not likely to be associated with AFFs in Asian female chronic bisphosphonate users. Hip Structural Analysis does not show an increased predilection for tensile failure in AFFs.     

Modifiable determinants of bone status in young women

The purpose of this study was to evaluate the contributions of exercise, fitness, body composition, and calcium intake during adolescence to peak bone mineral density and bone structural measurements in young women. University Hospital and 75 healthy, white females in the longitudinal Penn State Young Women's Health Study were included. Body composition, total body, and hip bone mineral density (BMD) were measured by dual-energy X-ray absorptiometry (DXA), exercise scores by sports-exercise questionnaire during ages 12-18 years, and estimated aerobic capacity by bike ergometry. Section modulus values (a measurement of bending strength) cross-sectional area (CSA), subperiosteal width, and cortical thickness were calculated from DXA scan data for the femoral neck and femoral shaft. Calcium intakes were calculated from 39 days of prospective food records collected at 13 timepoints between ages 12 and 20 years; supplemental calcium intakes were included. Section moduli at the femoral neck and shaft were correlated significantly with lean body mass, sports-exercise scores (R(2) = 0.07-0.19, p < 0.05), and aerobic capacity (R(2) = 0.06-0.57, p < 0.05). Sports-exercise scores correlated with BMD at the femoral neck and shaft. Average total daily calcium intake at age 12-20 years ranged from 486 to 1958 mg/day and was not significantly associated with total or regional peak BMD or bone structure measures at 20 years of age. It was shown that achievable levels of exercise and fitness have a favorable effect on BMD and section modulus of the femoral neck and femoral shaft in young adult women, whereas daily calcium intake of >500 mg in female adolescents appears to have little, if any effect.     

Racial/ethnic differences in bone mineral density among older women

The epidemiologic information regarding international differences in bone mineral density (BMD) in women is currently insufficient. We compared BMD in older women across five racial/ethnic groups in four countries. The femoral neck, total hip, and lumbar spine BMD were measured in women (aged 65–74 years) from the Study of Osteoporotic Fractures (SOF) (5,035 Caucasian women and 256 African American women in the US), the Tobago Women’s Health Study (116 Afro-Caribbean women), the Ms Os Hong Kong Study (794 Hong Kong Chinese women) and the Namwon Study (1,377 South Korean women). BMD was corrected according to the cross-site calibration results for all scanners. When compared with US Caucasian women, the age adjusted mean BMD measurements at the hip sites were 21–31 % higher among Tobago Afro-Caribbean women and 13–23 % higher among African American women. The total hip and spine BMD values were 4–5 % lower among Hong Kong Chinese women and 4–7 % lower among South Korean women compared to US Caucasians. The femoral neck BMD was similar in Hong Kong Chinese women, but higher among South Korean women compared to US Caucasians. Current/past estrogen use was a significant contributing factor to the difference in BMD between US versus non-US women. Differences in body weight partially explained the difference in BMD between Asian versus non-Asian women. These findings show substantial racial/ethnic differences in BMD even within African or Asian origin individuals, and highlight the contributing role of body weight and estrogen use to the geographic and racial/ethnic variation in BMD.     

Bone Mineral Density and Hip Axis Length in Singapore''s Multiracial Population

Ethnic differences in bone density and hip geometry are known to exist, even within the same population. A recent study in Singapore showed that there were significant racial differences in hip fracture rates, with Chinese having the highest incidence of hip fractures. The aim of this study was to compare the bone mineral density (BMD) and hip axis length in Chinese, Malay, and Indian women. A total of 1575 women aged 20-59 yr were recruited, of which 77.6% (1222) were Chinese, 7.7% (122) Malays, and 14.7% (231) Indians. There was no significant difference in peak BMD of both lumbar spine and femoral neck among the three ethnic groups. However, in the older age group (50-59 yr), both Chinese and Malay women had significantly lower femoral neck BMD compared to Indian women. There was no significant loss in BMD of the lumbar spine between the second and fifth decades in all the three races. Between the second and fifth decade, Chinese and Malay women had significant bone loss in the femoral neck of 6.6% and 8.2%, respectively, whereas Indian women did not show any significant bone loss. Chinese women had significantly longer hip axis length compared to either Malay or Indian women (9.87 +/- 0.52 cm vs 9.67 +/- 0.49 cm; p < 0.005; and 9.69 +/- 0.55 cm, p < 0.05, respectively). The initial findings suggest racial differences in bone density and hip geometry exist in the local community. Future research should include prospective, longitudinal studies to determine the age-related bone loss in these three racial groups. It is also important to investigate the differences of spine and hip fracture rates and their relationship with bone density and hip axis length.     

Association of Selective Serotonin Reuptake Inhibitors and Bone Mineral Density in Elderly Women

Depression and osteoporosis are 2 common comorbidities in geriatric patients. There are concerns about the deleterious effects of selective serotonin reuptake inhibitor (SSRI) antidepressant use on bone mineral density (BMD). We examined the association between SSRI use and BMD in elderly women (≥65?yr) referred to a geriatric osteoporosis clinic for bone health evaluation. Cross-sectional analyses using the general linear model were performed on data collected retrospectively from August 2010 to April 2015. A total of 250 women were seen during the study period. Of these, 140 women had complete data on BMD measurements: 22 (15.7%) used an SSRI and 118 (84.3%) did not. The 2 groups, SSRI users and SSRI nonusers, did not differ significantly across any of the covariates tested (age, ethnicity, body mass index, and past and present osteoporosis treatment medications). After adjusting for covariates, there was no difference in the BMDs at the femoral neck (p?=?0.887) or the spine (p?=?0.275) between the 2 groups. Similarly, no difference was seen in the T-scores between SSRI users and nonusers at the femoral neck (p?=?0.924) or at the spine level (p?=?0.393). Our study did not show an association between SSRI use and BMD among elderly women referred for bone health evaluation. Other studies in the literature have been inconclusive, and therefore, robust longitudinal studies are needed to further assess the interaction between SSRI use and predictors of fracture such as BMD, bone turnover markers, and genes involved in bone turnover. Until then, clinicians should closely monitor the bone health of long-term SSRI users.