Osteoporosis in Indian women aged 40–60 years

Summary

The study investigates BMD pattern in Indian women aged 40–60 years through a retrospective assessment using DEXA scan of hip and spine of 1,282 asymptomatic Indian women. The Study group indicated high incidence of decreased bone mass and significantly lower BMD as compared to western and other Asian counterparts.

Introduction

An understanding of BMD pattern in women aged 40–60 years is crucial for prevention, diagnosis of osteoporosis and management of its complications in later life. Hence, the present study investigates BMD in Indian women aged 40–60 years for which no data exists in literature.

Method

A retrospective assessment of BMD by DEXA scan of hip and spine of 1,282 asymptomatic women in age group 40–60 was performed. Standardized BMD was calculated and compared with other population groups.

Results

Osteoporosis and osteopenia are widely prevalent among females of the 40–60 age group as a meager 35% of subjects had normal bone density. Average BMD of spine was 0.89 (SD 0.14) gm/cm² and average BMD of hip was 0.85(0.15) gm/cm². The correlation between BMD and age was negative. Spine DEXA was found to be more significant than hip DEXA (p value?<?0.0001) for osteoporosis assessment. Similarly, T scores of spine were more significantly correlated in this age group (p value?<?0.0001) for osteoporosis than hip T scores.

Conclusion

The study group indicated high incidence of decreased bone mass, and significantly lower BMD as compared to western and other Asian counterparts. This study emphasizes on early screening and treatment in study group to avoid long-term complications.     

Forearm bone mineral density changes during postpartum and the effects of breastfeeding, amenorrhea, body mass index and contraceptive use

Summary

Prospective cohort study performed to evaluate bone mineral density (BMD) changes up to 12?months postpartum of healthy women and its association with breastfeeding, contraceptive methods, amenorrhea, and body mass index (BMI). There is a trend in bone loss during the first 6?months with posterior recovery, with evidence of a protective effect of hormonal contraception.

Introduction

This study was conducted to evaluate bone mineral density (BMD) changes during postpartum period among healthy women and its association with breastfeeding, use of contraceptive methods, amenorrhea and body mass index (BMI).

Methods

A prospective cohort study including 100 healthy women. Distal BMD was measured 7–10?days, 3, 6, and 12?months postpartum at the nondominant forearm using dual-energy X-ray absorptiometry. Data about breastfeeding duration, amenorrhea, contraceptive use and BMI were collected.

Results

Seventy-eight women had a complete set of BMD measurements. The mean duration of exclusive breastfeeding was 125.9 (±66.6) days, with a median total lactation period of 263.5?days. The mean duration of amenorrhea was 164.2 (±119.2) days. BMD measurements showed a significant decrease in the distal radius, however with no significance in the ultradistal radius. When considering only the nonhormonal contraceptive users, the difference at 12?months was significant. Multivariate analysis of variance showed that both BMI and contraceptive use were significantly correlated with BMD. Multiple linear regression analysis showed significant correlation of distal radius with baseline BMD at the same site, pregestational BMI, age, years of schooling and difference in BMI. For ultradistal radius, there was a significant direct correlation with its baseline BMD and pregestational BMI.

Conclusions

There was a trend in bone loss during the first 6?months postpartum with posterior recovery. Also, hormonal contraceptive methods provided protection of bone loss. However, the long duration of breastfeeding and the follow-up were not sufficient to draw definitive conclusions on postweaning BMD conditions.     

Peak bone mineral density in Vietnamese women

Summary

This cross-sectional study showed that peak bone mineral density in Vietnamese women is comparable to that in Caucasian women; however, the prevalence of osteoporosis in post-menopausal Vietnamese women was slightly higher than in Caucasian women. The age of achieving peak bone mass in Vietnamese women was between 26 and 30 years.

Introduction

While peak bone mass and its determinants have been well-documented in Caucasian populations, little has been studied in Asian populations. The present study was designed to estimate the peak bone mineral density (BMD), age of its attainment, and to examine the prevalence of osteoporosis in Vietnamese women aged 50+.

Methods

The study was designed as a cross-sectional study with 328 women aged between 10 and 65 years (average age: 41) who were randomly selected from two districts around Hanoi city according to a stratified sampling scheme. BMD at the lumbar spine, femoral neck and total hip was measured by a DXA instrument (GE Lunar Prodigy, WI, USA). BMD was modeled as a cubic function of age, from which peak BMD and age at peak BMD were estimated. Bootstrap method was utilized to estimate the 95% confidence interval of peak BMD and age at peak BMD. From the peak BMD, T-score was calculated for each woman, and using the World Health Organization criteria, any woman with femoral neck BMD T-score ≤ -2.5 was classified as having osteoporosis.

Results

Peak BMD was estimated at 1.16 g/cm² (standard deviation [SD]: 0.13 g/cm²) at the lumbar spine, 1.02 g/cm² (SD 0.12) at the total hip, and 0.94 g/cm² (SD 0.11) at the femoral neck. In the cubic polynomial model, the age at peak BMD was estimated to range between 27 and 29 years. The prevalence of osteoporosis among those aged between 50 and 65 years was 23%. This prevalence was higher than in Chinese, Japanese, Korean and Caucasian populations.

Conclusion

These data suggest that although the peak BMD in Vietnamese women is comparable to, the prevalence of osteoporosis is higher than, in some other Asian and Caucasian women. It seems that osteoporosis is an important public health burden in Vietnam.     

Predictors of Bone Mineral Density Improvement in Patients Undergoing Parathyroidectomy for Primary Hyperparathyroidism

Introduction

Primary hyperparathyroidism (PHPT) results in increased bone turnover, resulting in bone mineral density (BMD) reduction and a predisposition towards fractures. Parathyroidectomy (PTX) is the only definitive cure.

Objective

The primary goals of this study were to investigate the impact of PTX on BMD in patients with PHPT and to identify factors associated with post-operative BMD improvement using a multivariate model.

Methods

Between 1999 and 2010, a total of 757 patients underwent PTX for treatment of PHPT; 123 patients had both a pre- and a post-operative dual-energy X-ray absorptiometry (DEXA) scan. A prospective database was queried to obtain information about patient demographics, medications, comorbidities, and pre- and post-operative laboratory values. A Cox regression model was used to stratify patients and to identify factors that independently predict BMD response following PTX in this patient population.

Results

Overall, mean percent change in BMD was +12.31 % at the spine, +8.9 % at the femoral neck (FN), and +8.5 % at the hip, with a mean follow-up of 2.3 ± 1.5 years. A total of 101 (82.1 %) patients had BMD improvement at their worst pre-operative site. In patients who improved, 69.9 % (n = 86) had >5 % increase. Factors associated with BMD improvement at the worst pre-operative site were as follows: male gender (hazard ratio [HR] 2.29; 95 % confidence interval [CI] 1.54–4.21); pre-operative BMD with T-score less than ?2.0 (HR 1.89; 95 % CI 1.11–2.39); age <55 years (HR 1.74; 95 % CI 1.14–2.25); BMD DEXA scan at >2.5 years post-operatively (HR 1.71; 95 % CI 1.09–2.17); history of previous fracture (HR 1.24; 95 % CI 1.05–1.92); and private insurance (HR 1.18; 95 % CI 1.06–2.1). The use of bisphosphonates, estrogens, vitamin D supplementation, or tobacco; obesity; history of previous PTX, serum calcium or parathyroid hormone levels were not independently associated with post-operative BMD improvement.

Conclusion

Osteoporosis is one of the established National Institutes of Health criteria for PTX in asymptomatic patients with PHPT, but BMD improvement is not consistently seen during the post-operative period. Gender, age, more severe pre-operative bone disease, and insurance status were all predictors for greater BMD improvement following PTX. Further studies with a rigorous post-operative BMD regimen are needed in order to validate these results.     

Short-term in vivo precision of BMD and parameters of trabecular architecture at the distal forearm and tibia

Summary

In vivo hr-pQCT precision was determined in 42 postmenopausal women using double baseline measurements from a multicenter trial of odanacatib. Errors, e.g., at the radius below 1.3% for BMD and below 6.3% for trabecular structure, were comparable to single-center results. Motion artifacts remain a challenge, particularly at the forearm.

Introduction

The short-term in vivo precision of BMD, trabecular bone structure, cortical thickness and porosity of the forearm and tibia was measured by hr-pQCT. Also the effect of image quality on precision was evaluated.

Methods

In 42 postmenopausal women (age 64.4?±?6.8?years) out of 214 subjects enrolled in a multi center advanced imaging phase III study of odanacatib (DXA spine or hip T-scores between ?1.5 and ?3.5), double baseline hr-pQCT (XtremeCT) measurements with repositioning were performed. The standard ultradistal location and a second, more proximally located VOI were measured at the radius and tibia to better assess cortical thickness and porosity. Image analysis and quality grading (grades: perfect, slight artifacts, pronounced artifacts, unacceptable) were performed centrally.

Results

At the radius RMS%CV values varied from 0.7% to 1.3% for BMD and BV/TV and from 5.6% to 6.3% for Tb.Sp, Tb.Th, Tb.N, and cortical porosity. Numerically at the tibia, precision errors were approx. 0.5% lower for BMD and 1% to 2% lower for structural parameters although most differences were insignificant. In the radius but not in the tibia, precision errors for cortical thickness were smaller at the distal compared to the ultradistal location (1% versus 2%).

Conclusions

BMD precision errors were lower than those for trabecular architecture and cortical porosity. Motion artifacts remain a challenge, particularly at the forearm. Quality grading remains subjective, and more objective evaluation methods are needed. Precision in the context of a multicenter clinical trial, with centralized training and scan analysis, was comparable to single-center results previously reported.     

Bone mineral density by DXA and HR pQCT can discriminate fracture status in men and women with stages 3 to 5 chronic kidney disease

Summary

Fractures are common in chronic kidney disease (CKD). We determined if bone mineral density testing by dual energy X-ray absorptiometry (DXA) and high resolution peripheral quantitative computed tomography (HR pQCT) could discriminate fracture status in CKD patients. Both tests were able to discriminate fracture status. Further, the addition of HR pQCT measurements to DXA measurements did not improve fracture discrimination.

Introduction

The optimal method to identify individuals with CKD at high fracture risk is unknown.

Methods

We determined if bone mineral density (BMD) by DXA and HR pQCT could discriminate fracture status in 211 adult men and women with stages 3 to 5 CKD, attending predialysis clinics in Toronto Canada, using logistic regression. Results are expressed as the odds ratio (OR) of fracture (prevalent vertebral and/or low trauma since age 40?years) per standard deviation decrease in the predictor adjusted for age, weight, sex, and CKD stage. We constructed receiver operating characteristic curves to examine the discriminative ability of BMD measures for fracture.

Results

Most participants were Caucasian men with a mean age of 63.3?±?15.5?years. There were 77 fractures in 74 participants. Decreases in BMD were associated with increased fracture risk: OR?=?1.56 (95% confidence interval (CI), 1.41 to 1.71) for BMD by DXA at the ultradistal radius, and OR?=?1.24 (95% CI, 1.12 to 1.36) for cortical area by HR pQCT. Further, while both tests were able to discriminate fracture status, the addition of HR pQCT measures to BMD by DXA did not improve fracture discrimination ability.

Conclusions

Among CKD patients not yet requiring renal replacement therapy, BMD by DXA is able to discriminate fracture status.     

Attenuation of Postmenopausal Bone Loss in Patients with Transient Hypoparathyroidism After Total Thyroidectomy

Background

Increased bone mineral density (BMD) has been reported in patients with postsurgical permanent hypoparathyroidism. Hypoparathyroidism may attenuate the high-turnover bone loss in postmenopausal women. We reported previously that patients who had transient hypoparathyroidism postoperatively were at subclinical hypoparathyroid (hP) status even 5 years after surgery. We hypothesized that patients with transient hypoparathyroidism (ThP) may have altered BMD.

Methods

A total of 140 women who underwent total thyroidectomy had BMD measurements of the lumbar spine, femoral neck, and radius 3 years after surgery. At surgery, 99 patients were ≥50 years and 41 were <50 years. They were divided into three groups according to their postoperative parathyroid function: There were 80 patients in the no hP (NhP) group, 54 in the ThP group, and 6 in the permanent hP (PhP) group.

Results

Among the 99 patients aged ≥50 years, 36 ThP patients had median Z scores of the BMD in all three areas (lumbar spine, femoral neck, radius) that were significantly higher (by 1.083, 0.533, and 1.047, respectively) than those in the 60 NhP patients aged ≥50 years. The BMDs in the three PhP patients ≥50 years were higher than those in the NhP and ThP patients, but the difference did not reach significance except for in the femoral neck. Multivariate logistic regression analyses showed that Z scores > 0 were significantly associated only with the presence of ThP postoperatively. In the patients <50 years, the BMD values were not significantly different among the three groups except at the radius in PhP patients, which was significantly lower than those of the other patients.

Conclusions

We found that ThP was associated with increased BMD in postmenopausal women. This may be due to attenuation of the high-turnover bone loss in postmenopausal women.     

Bone mineral density and parathyroid function in patients on maintenance hemodialysis

Background

The relationship between parathyroid function, an important determinant of bone turnover, and bone mineral density (BMD) in patients with chronic kidney disease is not fully understood. We wanted to analyze the association between BMD and parathyroid function in hemodialysis patients in details.

Methods

In a cross-sectional design, data from 270 patients (age 55 ± 15 years, 60% men, all Caucasian) on maintenance hemodialysis were analyzed. All patients underwent dual energy X-ray absorptiometry of the lumbar spine (LS), femoral neck (FN) and distal radius (DR). In addition to routine laboratory tests, blood samples were collected for iPTH, serum markers of bone metabolism (alkaline phosphatase, type I collagen crosslinked-C-telopeptide) and 25OH vitamin D.

Results

Based on Z-scores, bone mineral density was moderately reduced only at the femoral neck in the total cohort. The average Z-score of the ??low PTH?? group (iPTH < 100 pg/ml) was not different from the Z-score of patients with iPTH in the ??target range?? (100?C300 pg/ml) at any measurement site. While iPTH was negatively correlated with BMD at all measurement sites in patients with iPTH > 100 pg/ml (rho = ?0.255, ?0.278 and ?0.251 for LS, FN and DR, respectively, P < 0.001 for all), BMD was independent of iPTH in patients with iPTH < 100 pg/ml. Furthermore, iPTH was not associated with serum markers of bone metabolism, but these markers were negatively correlated with BMD in the ??low PTH?? group.

Conclusions

Low PTH levels are not associated with low BMD in patients with end-stage kidney disease. Furthermore, bone metabolism seems to be independent of iPTH in patients with relative hypoparathyroidism likely reflecting skeletal resistance to PTH.     

Comparison of the effects of three oral bisphosphonate therapies on the peripheral skeleton in postmenopausal osteoporosis: the TRIO study

Summary

We compared the effects of oral alendronate, ibandronate and risedronate on the central and peripheral skeleton over 2 years. We report differences in effect on the central skeleton but not on the peripheral skeleton. Greater effects were observed for ibandronate (and alendronate) than risedronate at the spine but not the hip.

Introduction

Generally, comparative clinical trials of bisphosphonates have examined changes in bone within central skeletal regions. We have examined the effects of bisphosphonate treatment on the peripheral skeleton.

Methods

We conducted a 2-year, open-label, parallel randomised control trial of three orally administered bisphosphonates, at their licensed dose, to examine and compare their effects on the peripheral skeleton using multiple modes of measurement. We studied 172 postmenopausal women (53–84 years) who had either a bone mineral density (BMD) T-score of? ≤??2.5 at the spine and/or total hip or ?Premenopausal women (33–40 years, n?=?226) were studied to monitor device stability.

Results

We measured central BMD of the lumbar spine, total hip, total body and forearm using dual-energy X-ray absorptiometry. We measured calcaneus BMD (using dual-energy X-ray absorptiometry plus laser), radius and tibia BMD (using peripheral quantitative computed tomography), finger BMD (using radiographic absorptiometry), and phalangeal and calcaneal ultrasound variables (using quantitative ultrasound). Mixed effects regression models were used to evaluate effects of time and treatment allocation on BMD change. By 2 years, there were significant increases (p?Conclusions The increases in lumbar spine and total body BMD were greater with ibandronate and alendronate than with risedronate. Treatment effects on peripheral measurements did not differ between the three bisphosphonates.     

Role of bone mineral density in predicting morphometric vertebral fractures in patients with HIV infection

Summary

This study investigated the bone of HIV patients both in terms of quantity and quality. It was found that HIV-infected patients did fracture independently of the degree of bone demineralization as in other forms of secondary osteoporosis.

Introduction

We aimed to determine the prevalence of vertebral fractures (VFs) in HIV patients who were screened by bone mineral density (BMD) and to explore possible factors associated with VFs.

Methods

This is a cross-sectional study that included HIV-infected patients recruited in the Clinic of Infectious and Tropical Diseases and that underwent BMD measurement by dual-energy X-ray absorptiometry (DXA) at the lumbar spine and hip (Lunar Prodigy, GE Healthcare). For the assessment of VFs, anteroposterior and lateral X-ray examinations of the thoracic and lumbar spines were performed and were centrally digitized. Logistic regression models were used in the statistical analysis of factors associated with VFs.

Results

One hundred thirty-one consecutive patients with HIV infection (93 M, 38 F, median age 51 years; range, 36-75) underwent BMD measurement: 25.2 % of patients showed normal BMD, while 45 % were osteopenic and 29.7 % osteoporotic. Prevalence of low BMD (osteopenia and osteoporosis) was higher in females as compared to males (90 vs 69 %) with no significant correlation with age and body mass index. VFs occurred more frequently in patients with low BMD as compared to patients with normal BMD (88.5 vs. 11.4 %; p?p?=?0.073). VFs were significantly associated with older age and previous AIDS events.

Conclusions

These results suggest a BMD 相似文献   

Positive skeletal effects of cladrin, a naturally occurring dimethoxydaidzein, in osteopenic rats that were maintained after treatment discontinuation

Summary

Effects of cladrin treatment and withdrawal in osteopenic rats were studied. Cladrin improved trabecular microarchitecture, increased lumbar vertebral compressive strength, augmented coupled remodeling, and increased bone osteogenic genes. A significant skeletal gain was maintained 4 weeks after cladrin withdrawal. Findings suggest that cladrin has significant positive skeletal effects.

Introduction

We showed that a standardized extract of Butea monosperma preserved trabecular bone mass in ovariectomized (OVx) rats. Cladrin, the most abundant bioactive compound of the extract, promoted peak bone mass achievement in growing rats by stimulating osteoblast function. Here, we studied the effects of cladrin treatment and withdrawal on the osteopenic bones.

Methods

Adult female Sprague–Dawley rats were OVx and left untreated for 12 weeks to allow for significant estrogen deficiency-induced bone loss, at which point cladrin (1 and 10 mg/kg/day) was administered orally for another 12 weeks. Half of the rats were killed at the end of the treatments and the other half at 4 weeks after treatment withdrawal. Sham-operated rats and OVx rats treated with PTH or 17β-estradiol (E2) served as various controls. Efficacy was evaluated by bone microarchitecture using microcomputed tomographic analysis and fluorescent labeling of bone. qPCR and western blotting measured mRNA and protein levels in bone and uterus. Specific ELISA was used for measuring levels of serum PINP and urinary CTx.

Results

In osteopenic rats, cladrin treatment dose dependently improved trabecular microarchitecture, increased lumbar vertebral compression strength, bone formation rate (BFR), cortical thickness (Cs.Th), serum PINP levels, and expression of osteogenic genes in bones; and reduced expression of bone osteoclastogenic genes and urinary CTx levels. Cladrin had no uterine estrogenicity. Cladrin at 10 mg/kg maintained acquired skeletal gains 4 weeks after withdrawal.

Conclusion

Cladrin had positive skeletal effects in osteopenic rats that were maintained after treatment withdrawal.     

Fracture risk among older men: osteopenia and osteoporosis defined using cut-points derived from female versus male reference data

Summary

We explored the effect of using male and female reference data in a male sample to categorise areal bone mineral density (BMD). Using male reference data, a large proportion of fractures arose from osteopenia, whereas using female reference data shifted the fracture burden into normal BMD.

Introduction

The purpose of this study was to describe fracture risk associated with osteopenia and osteoporosis in older men, defined by areal BMD and using cut-points derived from male and female reference data.

Methods

As part of the Geelong Osteoporosis Study, we followed 619 men aged 60–93 years after BMD assessments (performed 2001–2006) until 2010, fracture, death or emigration. Post-baseline fractures were radiologically confirmed, and proportions of fractures in each BMD category were age-standardised to national profiles.

Results

Based on World Health Organization criteria, and using male reference data, 207 men had normal BMD at the femoral neck, 357 were osteopenic and 55 were osteoporotic. Using female reference data, corresponding numbers were 361, 227 and 31. During the study, 130 men died, 15 emigrated and 63 sustained at least one fracture. Using male reference data, most (86.5 %) of the fractures occurred in men without osteoporosis on BMD criteria (18.4 % normal BMD, 68.1 % osteopenia). The pattern differed when female reference data were used; while most fractures arose from men without osteoporosis (88.2 %), the burden shifted from those with osteopenia (34.8 %) to those with normal BMD (53.4 %).

Conclusions

Decreasing BMD categories defined increasing risk of fracture. Although men with osteoporotic BMD were at greatest risk, they made a relatively small contribution to the total burden of fractures. Using male reference data, two-thirds of the fractures arose from men with osteopenia. However, using female reference data, approximately half of the fractures arose from those with normal BMD. Using female reference data to define osteoporosis in men does not appear to be the optimal approach.     

Time dependency of bone density estimation from computed tomography with intravenous contrast agent administration

Summary

Our study has demonstrated that in contrast-enhanced multi-detector computed tomography (MDCT)-based bone density measurements, the scan delay time after contrast agent administration is a statistically significant variable for the derivation of quantitative computed tomography (QCT)-equivalent bone mineral density (BMD) values.

Introduction

Earlier investigators have proposed to derive QCT-equivalent BMD values from contrast-enhanced MDCT scans by using a merely density-based conversion equation. The purpose of this study was to investigate whether the scan delay after intravenous (IV) contrast agent administration might affect BMD values derived in this way.

Methods

A retrospective data analysis was performed on 198 subjects who underwent standardized biphasic MDCT. Average densities values (in Hounsfield units) of lumbar vertebral bodies 1 to 3 (L1–L3) were compared between phases I and II of the biphasic MDCT scan. Furthermore, QCT-equivalent BMD (BMD_QCT) values were calculated using a previously published conversion equation.

Results

Paired t-test analysis revealed that IV contrast agent administration leads to a statistically significant increase (8.6 %; p?<?0.0001) in overall density of L1–L3 from phases I to II. Moreover, comparison of BMD_QCT values between phases I and II reveals a change from osteoporotic to osteopenic in 4.5 % of the study population and from osteopenic to normal for 11.1 % of the subjects. Furthermore, it was revealed that the density increase from phases I to II shows a weak, yet statistically significant (p?<?0.001) age dependency.

Conclusions

Our study demonstrates that the use of a mere density-based conversion equation for deriving BMD_QCT from MDCT scans ignores time dependency as an important variable. Furthermore, our results indicate that the actual age-dependent BMD itself might be another relevant variable that needs to be included in a MDCT-to-QCT conversion equation.     

Short- and Mid-term Changes in Bone Mineral Density After Laparoscopic Sleeve Gastrectomy

Background

Bariatric surgery is the most effective treatment for achieving a significant weight loss. Morbidities present a significant reduction after bariatric surgery, but it may also result in several health complications, related to nutritional deficiencies, including bone metabolism. Several studies have reported a decrease in bone mineral density (BMD), but most of them referring to malabsorptive procedures. Restrictive procedures do not imply changes in gastrointestinal anatomy, so that one may expect fewer metabolic disturbances.

Methods

We performed a retrospective observational study of all morbidly obese patients undergoing LSG between 2008 and 2011 at our institution. Bone densitometry was performed before surgery and 1 and 2 years after the intervention. Body size measurements, analytical variables and densitometric values in the lumbar spine (BMD, t score and z score) were investigated.

Results

Forty-two patients were included, 39females and 3males. Mean BMI was 51.21 kg/m². Mean excessive BMI loss was 79.9 % after 1 year and 80.6 % after 2 years. Mean BMD values for spine increased progressively, reaching statistical significance at 1 and at 2 years. Percentage of BMD increase was 5.7 % at 1 year and 7.9 % at 2 years. An inverse correlation was observed between BMD increase and parathyroid hormone (PTH) decrease and a direct correlation between BMD and vitamin D increase.

Conclusion

Bone mineral density showed a progressive increase during the first and second year after sleeve gastrectomy. BMD changes are not associated with weight loss, but showed a direct correlation with vitamin D and an inverse correlation with PTH levels.     

International variation in proximal femur bone mineral density

Summary

We observed higher proximal femur bone mineral density (BMD) in European women compared to average values derived from US Caucasian women in the National Health and Nutrition Examination Survey (NHANES) study. Across European centres, Parisian women had lower proximal femur BMD compared to women from Kiel or Sheffield.

Introduction

Proximal femur BMD of US adults (NHANES III) may not accurately reflect that of European women. We examined the heterogeneity of BMD across European and US Caucasian women and across different European populations.

Methods

Proximal femur BMD was measured in women ages 20–39 years (n?=?258) and 55–79 years (n?=?1,426) from three European centres. Cross-calibrated BMD for total hip, femoral neck, trochanter and intertrochanter were examined. International variation in BMD was assessed by comparing means and SDs in the European data with those from the US NHANES III study. European populations were stratified into 5-year age bands to establish individual centre reference intervals. Between-centre differences were assessed using ANOVA and post hoc Fisher’s least significant difference tests.

Results

European women had higher BMD than US women: The differences were 7.1% to 14.2% (p?<?0.001) and 0% to 3.9% (p?<?0.05) in the older and younger women, respectively. Standard deviations for BMD at the different sites were comparable to those for US women. Among older, but not younger European women, proximal femur BMD was significantly lower in French women (Paris) than in women from Germany (Kiel) or the UK (Sheffield) (difference?=?5.0% to 9.6%, p?<?0.05).

Conclusions

International variation in hip BMD does exist, with international and between-centre differences being less evident at the femoral neck.     

Missense polymorphisms of the WNT16 gene are associated with bone mass, hip geometry and fractures

Summary

Two missense polymorphisms of WNT16 were associated with hip bone mineral density (BMD), the buckling ratio of the femoral neck, calcaneal ultrasound and hip fractures in individuals under 80 years of age. These results confirm the association of the WNT16 gene with bone mass and osteoporotic fractures.

Introduction

Osteoporosis has a strong genetic component. Wnt ligands stimulate the differentiation of osteoblast precursors and play a major role in skeletal homeostasis. Therefore, the aim of this study was to explore the association of allelic variants of the WNT16 gene with BMD, other structural parameters of bone and osteoporotic hip fractures.

Methods

Six single nucleotide polymorphisms were analysed in 1,083 Caucasian individuals over 49 years of age.

Results

Two missense polymorphisms (rs2908004 and rs2707466) were associated with femoral neck BMD, with average differences across genotypes of 35 mg/cm² (p?=?0.00037 and 0.0015, respectively). Likewise, the polymorphisms were associated with calcaneal quantitative ultrasound parameters (p?=?0.00004 and 0.0014, respectively) and the buckling ratio, an index of cortical instability of the femoral neck (p?=?0.0007 and 0.0029, respectively). Although there were no significant differences in the genotype frequency distributions between 294 patients with hip fractures and 670 controls, among the subgroup under 80 years of age, TT genotypes were underrepresented in patients with fractures (odds ratio 0.50; CI 0.27–0.94).

Conclusion

Common missense polymorphisms of the WNT16 gene are associated with BMD at the hip, calcaneal ultrasound and the buckling ratio of the femoral neck, as well as with hip fractures in individuals under 80 years of age. Overall, these results confirm the association of the WNT16 locus with BMD identified in genome-wide association studies and support its role in determining the risk of osteoporotic fractures.     

The association between higher serum ferritin level and lower bone mineral density is prominent in women ≥45 years of age (KNHANES 2008–2010)

Summary

Data gathered from a nationally representative cohort demonstrate that higher serum ferritin levels are significantly associated with lower bone mass at various skeletal sites and the increased prevalence of osteoporosis and fractures, especially in women ≥45 years of age.

Introduction

Despite extensive in vitro and in vivo studies showing the detrimental effects of iron on bone metabolism, the clinical studies relating to osteoporosis-related phenotypes have not been evaluated extensively. In the present study, we investigated and compared the association between serum ferritin and bone mineral density (BMD), depending on the stratified age groups in both genders.

Methods

This is a population-based, cross-sectional study from the Korea National Health and Nutrition Examination Surveys, including 14,017 Koreans (6,817 men and 7,200 women) aged 10–80 years. BMD was measured using dual X-ray absorptiometry, and osteoporosis was diagnosed by the World Health Organization definition.

Results

Initially, we divided the subjects into three age groups, based on the patterns of age-related BMD changes in this national cohort (i.e., ≤24, 25–44, and ≥45 years old). Serum ferritin concentrations were inversely associated with BMD values at all measured sites after adjustment for confounders, only in women ≥45 years of age (P?=?0.041 to <0.001). Furthermore, when we divided these women into serum ferritin quartiles, the odds for prevalent osteoporosis and fractures were 1.55-fold (95 % CI?=?1.09–2.23) and 1.52-fold (95 % CI?=?1.02–2.27) higher, respectively, in subjects in the highest quartile compared with those in the lowest quartile.

Conclusions

These results provide the first clinical evidence that the associations between serum ferritin level and bone parameters could be the most prominent in women ≥45 years of age.     

Vertebral deformities and fractures are associated with MRI and pQCT measures obtained at the distal tibia and radius of postmenopausal women

Summary

We investigated the association of postmenopausal vertebral deformities and fractures with bone parameters derived from distal extremities using MRI and pQCT. Distal extremity measures showed variable degrees of association with vertebral deformities and fractures, highlighting the systemic nature of postmenopausal bone loss.

Introduction

Prevalent vertebral deformities and fractures are known to predict incident further fractures. However, the association of distal extremity measures and vertebral deformities in postmenopausal women has not been fully established.

Methods

This study involved 98 postmenopausal women (age range 60–88 years, mean 70 years) with DXA BMD T-scores at either the hip or spine in the range of ?1.5 to ?3.5. Wedge, biconcavity, and crush deformities were computed on the basis of spine MRI. Vertebral fractures were assessed using Eastell's criterion. Distal tibia and radius stiffness was computed using MRI-based finite element analysis. BMD at the distal extremities were obtained using pQCT.

Results

Several distal extremity MRI and pQCT measures showed negative association with vertebral deformity on the basis of single parameter correlation (r up to 0.67) and two-parameter regression (r up to 0.76) models involving MRI stiffness and pQCT BMD. Subjects who had at least one prevalent vertebral fracture showed decreased MRI stiffness (up to 17.9 %) and pQCT density (up to 34.2 %) at the distal extremities compared to the non-fracture group. DXA lumbar spine BMD T-score was not associated with vertebral deformities.

Conclusions

The association between vertebral deformities and distal extremity measures supports the notion of postmenopausal osteoporosis as a systemic phenomenon.     

Age-related decline in bone density among ethnically diverse older men

Summary

We compared rates of BMD decline in older men of diverse ethnic backgroud. The rate of bone loss was statistically equivalent between men of African and Caucasian descent.

Introduction

Race differences in peak bone mineral density (BMD) are well established, but the magnitude of bone loss among non-white men has not been well characterized. Our objective was to compare and contrast the rates of decline in BMD with aging among older men of different race/ethnic groups.

Methods

The rate of decline in hip BMD was measured by dual-energy X-ray absorptiometry (Hologic QDR-4500 W) with an average follow-up of 4.6?years in 3,869 Caucasian, 138 African American, 145 Asian, and 334 Afro-Caribbean men aged????65?years (Mean ages: 73?±?5, 70?±?4, 72?±?5, 71?±?5?years, respectively).

Results

The annual rate of decline in BMD at the femoral neck was ?0.32%, ?0.42%, ?0.09%, and ?0.44%/year for Caucasian, African American, Asian, and Afro-Caribbean men, respectively (p?<?0.05 for Caucasian versus Asian). Although men of African ancestry have higher peak BMD than Caucasians, rates of decline in BMD with aging appear to be statistically equivalent in our study. In contrast, Asian men experienced a slower rate of decline in BMD compared with Caucasians and African Americans.

Conclusion

More studies are needed to better define the natural history of and factors associated with bone loss among non-white men.     

Applying ethnic-specific bone mineral density T-scores to Chinese women in the USA

Summary

Caucasian reference data are used to classify bone mineral density in US women of all races. However, use of Chinese American reference data yields lower osteoporosis prevalence in Chinese women. The reduction in osteoporosis labeling may be relevant for younger Chinese women at low fracture risk.

Introduction

Caucasian reference data are used for osteoporosis classification in US postmenopausal women regardless of race, including Asians who tend to have lower bone mineral density (BMD) than women of white race. This study examines BMD classification by ethnic T-scores for Chinese women.

Methods

Using BMD data in a Northern California healthcare population, Chinese women aged 50–79 years were compared to age-matched white women (1:5 ratio), with femoral neck (FN), total hip (TH), and lumbar spine (LS) T-scores calculated using Caucasian versus Chinese American reference data.

Results

Comparing 4039 Chinese and 20,195 white women (44.8 % age 50–59 years, 37.5 % age 60–69 years, 17.7 % age 70–79 years), Chinese women had lower BMD T-scores at the FN, TH, and LS (median T-score 0.29–0.72 units lower across age groups, p?<?0.001) using Caucasian reference data. Using Chinese American BMD reference data resulted in an average +0.47, +0.36, and +0.48 units higher FN, TH, and LS T-scores, respectively, reducing the prevalence of osteoporosis (T-score?≤??2.5) in Chinese women at the FN (16.7 to 6.6 %), TH (9.8 to 3.2 %), and LS (23.2 to 8.9 %); osteoporosis prevalence at any one of three sites fell from 29.6 to 12.6 % (22.4 to 8.1 % for age 50–64 years and 43.2 to 21.0 % for age 65–79 years).

Conclusion

Use of Chinese American BMD reference data yields higher (ethnic) T-scores by 0.4–0.5 units, with a large proportion of Chinese women reclassified from osteoporosis to osteopenia. The reduction in osteoporosis labeling with ethnic T-scores may be relevant for younger Chinese women at low fracture risk.