Low bone turnover and low bone density in a cohort of adults with Down syndrome

Summary

Increased incidence of osteoporosis in Down syndrome has been reported, but etiology is not established. We report low bone turnover markers and bone mineral density (BMD) in a cohort of people with Down syndrome without consistent clinical risk factors. Our results should guide future studies and treatments for this common problem.

Introduction

To better understand the etiology for osteoporosis in Down syndrome (DS), we measured bone density by dual-energy X-ray absorptiometry (DXA) and circulating biochemical markers of bone formation and resorption in a cohort of 30 community-dwelling DS adults.

Methods

Seventeen males and 13 females followed in the University of Arkansas Down Syndrome Clinic were evaluated by DXA to estimate BMD and underwent phlebotomy to measure serum procollagen type-1 intact N-terminal propeptide (P1NP) to evaluate bone formation, and serum C-terminal peptide of type-I collagen (CTx) to evaluate bone resorption.

Results

Seven of 13 DS females and 12 of 17 DS males had low bone mass at one of measured sites (z?≤??2.0). When data were grouped by age, males had apparent osteopenia earlier than females. The mean P1NP in the normal group was 19.2?±?5.2 ng/ml vs. 2.2?±?0.9 ng/ml in the DS group (P?=?0.002). Serum CTx levels in the normal group were 0.4?±?0.1 ng/ml vs. 0.3?±?0.1 ng/ml (P?=?0.369).

Conclusions

Low BMD in adults with DS is correlated with a significant decrease in bone formation markers, compared to controls without DS, and is independent of gender. These data suggest that diminished osteoblastic bone formation and inadequate accrual of bone mass, with no significant differences in bone resorption, are responsible for the low bone mass in DS. These observations question the use of antiresorptive therapy in this population and focus attention on increasing bone mass by other interventions.     

Milk consumption throughout life and bone mineral content and density in elderly men and women

Summary

Association between bone mineral density and bone mineral content in old age and milk consumption in adolescence, midlife, and old age was assessed. The association was strongest for milk consumption in midlife: those drinking milk daily or more often had higher bone mineral density and content in old age than those drinking milk seldom or never.

Introduction

The role of lifelong milk consumption for bone mineral density (BMD) and bone mineral content (BMC) in old age is not clear. Here we assess the association between hip BMD and BMC in old age and milk consumption in adolescence, midlife, and current old age.

Methods

Participants of the Age, Gene/Environment Susceptibility-Reykjavik Study, aged 66–96 years (N?=?4,797), reported retrospective milk intake during adolescence and midlife as well as in current old age, using a validated food frequency questionnaire. BMC of femoral neck and trochanteric area was measured by volumetric quantitative computed tomography and BMD obtained. Association was assessed using linear regression models. Differences in BMC, bone volume, and BMD in relation to milk intake were portrayed as gender-specific Z-scores.

Results

Men consuming milk?≥?once/day during midlife had 0.21 higher Z-scores for BMD and 0.18 for BMC in femoral neck (95 % confidence interval 0.05–0.39 and 0.01–0.35, respectively) compared with?<?once/week. Results were comparable for trochanter. For women the results were similar, with slightly lower differences according to midlife milk consumption. For current and adolescent milk consumption, differences in Z-scores were smaller and only reached statistical significance in the case of BMD for current consumption in men, while this association was less pronounced for BMC.

Conclusions

Our data suggest that regular milk consumption throughout life, from adolescence to old age, is associated with higher BMC and BMD in old age, with no differences seen in bone volume. The strongest associations are seen for midlife milk consumption in both genders.     

Diagnostic evaluation of bone densitometric size adjustment techniques in children with and without low trauma fractures

Summary

Several established methods are used to size adjust dual-energy X-ray absorptiometry (DXA) measurements in children. However, there is no consensus as to which method is most diagnostically accurate. All size-adjusted bone mineral density (BMD) values were more diagnostically accurate than non-size-adjusted values. The greatest odds ratio was estimated volumetric BMD for vertebral fracture.

Introduction

The size dependence of areal bone density (BMD_a) complicates the use of DXA in children with abnormal stature. Despite several size adjustment techniques being proposed, there is no consensus as to the most appropriate size adjustment technique for estimating fracture risk in children. The aim of this study was to establish whether size adjustment techniques improve the diagnostic ability of DXA in a cohort of children with chronic diseases.

Methods

DXA measurements were performed on 450 children, 181 of whom had sustained at least one low trauma fracture. Lumbar spine (L₂–L₄) and total body less head (TBLH) Z-scores were calculated using different size adjustment techniques, namely BMD_a and volumetric BMD for age (bone mineral apparent density (BMAD)); bone mineral content (BMC) and bone area for height; BMC for bone area; BMC for lean mass (adjusted for height); and BMC for bone and body size.

Results

Unadjusted L₂–L₄ and TBLH BMD_a were most sensitive but least specific at distinguishing children with fracture. All size adjustments reduced sensitivity but increased post-test probabilities, from a pre-test probability of 40 % to between 58 and 77 %. The greatest odds ratio for fracture was L₂–L₄ BMAD for a vertebral fracture and TBLH for lean body mass (LBM) (adjusted for height) for a long bone fracture with diagnostic odds ratios of 9.3 (5.8–14.9) and 6.5 (4.1–10.2), respectively.

Conclusion

All size adjustment techniques improved the predictive ability of DXA. The most accurate method for assessing vertebral fracture was BMAD for age. The most accurate method for assessing long bone fracture was TBLH for LBM adjusted for height.     

Effect of alendronate in elderly patients after low trauma hip fracture repair

Summary

One year of once weekly alendronate, when given shortly after the surgical repair of a hip fracture, produces reductions in bone markers and increases proximal femoral bone density. The therapy was well tolerated.

Introduction

Hip fracture is the most devastating type of osteoporotic fracture and increases notably the risk of subsequent fractures. The aim of this paper was to evaluate the effects of 1 year therapy with a weekly dose of alendronate in the bone mineral density and bone markers in elderly patients after low trauma hip fracture repair.

Methods

Two hundred thirty-nine patients (81?±?7 years; 79.8% women) were randomized to be treated either with calcium (500 mg/daily) and vitamin D₃ (400 IU/daily; Ca–Vit D group) or with alendronate (ALN, 70 mg/week) plus calcium and vitamin D₃ (500 mg/daily and 400 IU/daily, respectively; ALN + Ca–Vit D group).

Results

One hundred forty-seven (61.5%) patients completed the trial. Alendronate increased proximal femoral bone mineral density (BMD) in the intention-to-treat analysis (mean difference (95% confidence interval); total hip 2.57% (0.67; 4.47); trochanteric 2.96% (0.71; 5.20), intertrochanteric 2.32% (0.36; 4.29)), but the differences were not significant in the BMD of the femoral neck (0.47%; (?2.03; 2.96) and the lumbar spine (0.69%; (?0.86; 2.23)). Bone turnover markers decreased during alendronate treatment.

Conclusion

The present study demonstrates for the first time the anti-resorptive efficacy of alendronate given immediately after surgical repair in an elderly population with recent hip fracture. This effect should positively affect the rate of subsequent fractures.     

Vitamin D2 from light-exposed edible mushrooms is safe, bioavailable and effectively supports bone growth in rats

Summary

Widespread poor vitamin D status, a health risk for bone disease, increases the need for new food sources of vitamin D. Light-exposed edible mushrooms synthesize vitamin D₂. Bioavailability, safety, and efficacy of high levels of vitamin D₂ from mushrooms to support bone health was established in chronically fed growing rats.

Introduction

Poor vitamin D status from reduced sun exposure is made worse by limited access to vitamin D-containing foods. Exposing white button mushrooms to ultraviolet B (UVB) light markedly increases their vitamin D₂ content, creating a new food source of vitamin D. We used a growing rat model to determine safety, bioavailability, and efficacy in support of bone growth by vitamin D₂ from UVB-exposed mushrooms.

Methods

We fed 150 weanling female rats one of five diets for 10 weeks, all formulated on AIN-93 G. Control diets contained no mushrooms either with or without vitamin D₃. Other diets contained 2.5% and 5.0% of UVB-exposed or -unexposed mushrooms. Safety of the high levels of vitamin D₂ from mushrooms was assessed by animal growth and by Von Kossa staining for soft tissue calcification. Bioavailability was determined from changes in circulating levels of 25-hydroxyvitamin D [25(OH)D] and parathyroid hormone (PTH). Efficacy in support of bone growth was determined from measures of femur bending properties, size, mineralization, and microarchitecture.

Results

Diets containing 2.5% and 5.0% light-exposed mushrooms significantly raised 25(OH)D and suppressed PTH levels compared to control-fed rats or rats fed 5.0% mushroom unexposed to light. Microarchitecture and trabecular mineralization were only modestly higher in the light-treated mushroom-fed rats compared to the controls. Von Kossa staining revealed no soft tissue calcification despite very high plasma 25(OH)D.

Conclusions

Vitamin D₂ from UVB-exposed mushrooms is bioavailable, safe, and functional in supporting bone growth and mineralization in a growing rat model without evidence of toxicity.     

Bone mass and density in preadolescent boys with and without Down syndrome

Summary

Preadolescent boys with Down syndrome at 7–10 years of age have lower bone mass and density in the pelvis than age-matched children without Down syndrome. However, bone mass and density of total body less head and lumbar spine are not different between these two groups.

Introduction

This study aimed to assess bone mineral content (BMC) and density (BMD) in preadolescent boys with and without Down syndrome (DS) at 7–10 years of age.

Methods

Eleven preadolescent boys with DS and eleven age-matched children without DS participated in this study. Dual-energy X-ray absorptiometry was used to measure BMC and BMD in whole body and lumbar spine. Both BMC and BMD of total body less head (TBLH) and lumbar spine (vertebrae L2–L4) were compared between the two groups, with and without adjusting for physical characteristics such as bone area, body height, and total lean mass. Two bone mineral apparent density (BMAD) variables were calculated to estimate volumetric BMD in the lumbar spine.

Results

Both BMC and BMD in the pelvis were lower in the DS group, after adjusting for physical characteristics. However, with and without adjusting for physical characteristics, the two groups were not different in BMC and BMD of the arms, legs, and TBLH from the whole body scan and in BMC, BMD, and BMAD of the lumbar spine from the lumbar spine scan.

Conclusions

These findings indicate that the pelvis may be the first site to show the significant difference in BMC and BMD between preadolescent boys with and without DS. It also suggests that significantly lower BMC and BMD in whole body and lumbar spine, which is usually observed in young adults with DS, may not occur before adolescence.     

Femur neck bone mineral density and fracture risk by age,sex, and race or Hispanic origin in older US adults from NHANES III

Summary

We provide the first reference values for bone mineral content and bone mineral density according to age and sex in Iranian children and adolescents. The prevalence of hypovitaminosis D was high, and levels of physical activity were low in our sample. Multiple regression analyses showed age, BMI, and Tanner stage to be the main indicators of bone mineral apparent density.

Purpose

Normal bone structure is formed in childhood and adolescence. The potential determinants which interact with genetic factors to influence bone density include gender, nutritional, lifestyle, and hormonal factors. This study aimed to evaluate bone mineral content (BMC) and the bone mineral density (BMD) and factors that may interfere with it in Iranian children.

Methods

In this cross-sectional study, 476 healthy Iranian children and adolescents (235 girls and 241 boys) aged 9–18 years old participated. BMC and BMD of the lumbar spine, femoral neck, and total body were measured by dual-energy X-ray absorptiometry using a Hologic Discovery device, and bone mineral apparent density (BMAD) of the lumbar spine and the femoral neck were calculated.

Results

We present percentile curves by age derived separately for BMC, BMD, and BMAD of the lumbar spine, left femoral neck, and total body excluding the head for boys and girls. Maximum accretion of BMC and BMD was observed at ages of 11–13 years (girls) and 12–15 years (boys).The prevalence of hypovitaminosis D was high and physical activity was low in our participants. However, in multiple regression analyses, age, BMI, and Tanner stage were the main indicators of BMD and BMAD

Conclusion

These normative data aid in the evaluation of bone density in Iranian children and adolescents. Further research to evaluate the evolution of BMD in Iranian children and adolescents is needed to identify the reasons for significant differences in bone density values between Iranian populations and their Western counterparts.     

Bone health status of premenopausal healthy adult females in Pakistani females

Summary

Bone health status in healthy premenopausal females was assessed. We found high bone turnover in 36.8?% and vitamin D deficiency and insufficiency in 82.8 and 16.1?%, respectively, and secondary hyperparathyroidism in 25.9?% of the subjects. This is alarming as there is inability to achieve peak bone mass and predisposes to osteoporosis risk.

Purpose

This study aimed to assess bone health status in healthy females by using biochemical markers of bone metabolism in blood [N-telopeptide of type I collagen (NTx), 25-hydroxyvitamin D (25OHD), and plasma intact parathyroid hormone (iPTH)].

Material and methods

One hundred and seventy-four healthy premenopausal female volunteers were recruited from an urban residential area in Karachi. Demographic details were collected on a preformed questionnaire. Blood samples for the estimation of serum NTx, 25OHD, and plasma iPTH were taken in a fasting state. Data were analyzed using Statistical Package for Social Sciences 16.0. A p value of <0.05 was considered as significant.

Results

High bone turnover, as depicted by NTx, was seen in 36.8?% cases. Vitamin D deficiency, insufficiency, and sufficiency were seen in 82.8, 16.1, and 1.1?% respectively. Secondary hyperparathyroidism was present in 25.9?% of the subjects, while others had blunted PTH response. Significant correlates of bone health were serum 25OHD levels, duration of sun exposure, and the practice of wearing veil (p value?<?0.001).

Conclusion

Bone turnover is high with high prevalence of vitamin D deficiency in apparently healthy premenopausal females predisposing them to higher risk for development of osteoporosis.     

Bone mineral density and bone turnover in non-cirrhotic patients with chronic hepatitis C and sustained virological response to antiviral therapy with peginterferon-alfa and ribavirin

Summary

Patients with chronic hepatitis C have low bone mineral density and increased bone resorption related to serum transaminase levels. Elevated serum soluble tumor necrosis factor (sTNFR-55) receptor levels may play a role in the bone mass loss in these patients. Bone mass is improved and bone turnover normalized in patients who respond to antiviral therapy with interferon and ribavirin.

Introduction

Low bone mineral density (BMD) has been described in patients with chronic hepatitis C (HCV). The study objective was to evaluate the effect of antiviral therapy on BMD and bone metabolism in non-cirrhotic HCV patients with sustained virological response.

Methods

We conducted a prospective study in 36 consecutive outpatients from the general community with non-cirrhotic HCV and an early and sustained virological response to peginterferon-alfa and ribavirin therapy. Determinations of BMD (dual X-ray absorptiometry at lumbar spine and femoral neck) and biochemical measurements of bone metabolism and sTNFR-55 were made at baseline, after 24 and 48 weeks of antiviral therapy, and at 48 weeks after the end of treatment.

Results

Patients had a significantly reduced BMD, which significantly increased during the follow-up. Serum levels of sTNFR-55 and bone turnover markers were increased at baseline and significantly reduced at all subsequent time points. We found an inverse correlation between BMD and both serum aminotransferase levels and urine deoxypyridinoline (D-pyr) and a positive correlation between serum aminotransferases and both urine D-Pyr and serum sTNFR-55.

Conclusions

Patients with chronic hepatitis C have low bone mass associated with increased bone resorption, and some relationship can be expected between serum aminotransferase levels and the degree of bone mass loss. Bone mass may be improved and bone turnover normalized in patients who respond to antiviral therapy. Elevated serum sTRFR-55 levels may play a role in the bone mass loss of these patients.     

Vitamin D status and physical activity interact to improve bone mass in adolescents. The HELENA Study

Summary

The effects of vitamin D concentrations on bone mineral content in adolescents are still unclear. Vitamin D and physical activity (PA) may interact to determine bone mineral content (BMC) in two possible directions; 25(OH)D sufficiency levels improve BMC only in active adolescents, or PA increases BMC in individuals with replete vitamin D levels.

Introduction

The effects of suboptimal 25-hydroxycholecalciferol (25(OH)D) concentrations on BMC in adolescents are still unclear. The main aim of this study was to evaluate the influence of 25(OH)D on BMC in adolescents, considering the effect of body composition, sex, age, Tanner stage, season, calcium and vitamin D intakes, physical fitness and PA.

Methods

Serum 25(OH)D concentrations, anthropometric measurements, dual energy X-ray absorptiometry measurements, calcium and vitamin D intakes, PA and physical fitness were obtained in 100 Spanish adolescents (47 males), aged 12.5–17.5?years, within the framework of the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study. Relations were examined using ANCOVA and regression analyses including BMC as dependent variable.

Results

Linear regression of BMC suggested that 25(OH)D concentrations independently influenced total and leg BMC after controlling for age, sex, lean mass, seasonality and calcium intake (B?=?0.328, p?B?=?0.221, p?p?Conclusions Vitamin D and PA may interact to determine BMC. 25(OH)D sufficiency levels improve bone mass only in active adolescents, or PA has a positive influence on BMC in individuals with replete vitamin D levels.     

Premenopausal women with idiopathic low-trauma fractures and/or low bone mineral density

Introduction

In men, idiopathic osteoporosis (IOP) is often associated with low serum insulin-like growth factor (IGF-1) and reduced bone formation. The characteristics of premenopausal women with IOP are not well defined. We aimed to define the clinical, reproductive, and biochemical characteristics of premenopausal women with unexplained osteoporosis.

Methods

This is a cross-sectional study of 64 women with unexplained osteoporosis, 45 with fragility fractures, 19 with low bone mineral density (BMD; Z-score less than or equal to ?2.0) and 40 normal controls. The following are the main outcome measures: clinical and anthropometric characteristics, reproductive history, BMD, gonadal and calciotropic hormones, IGF-1, and bone turnover markers (BTMs).

Results

Subjects had lower BMI and BMD than controls, but serum and urinary calcium, serum estradiol, vitamin D metabolites, IGF-1, and most BTMs were similar. Serum parathyroid hormone (PTH) and the resorption marker, tartrate-resistant acid phosphatase (TRAP5b), were significantly higher in both groups of subjects than controls and directly associated in all groups. Serum IGF-1 and all BTMs were directly associated in controls, but the association was not significant after controlling for age. There was no relationship between serum IGF-1 and BTMs in subjects. There were few differences between women with fractures and low BMD.

Conclusions

Higher serum TRAP5b and PTH suggest that increased bone turnover, possibly related to subclinical secondary hyperparathyroidism could contribute to the pathogenesis of IOP. The absence of differences between women with fractures and those with very low BMD indicates that this distinction may not be clinically useful to categorize young women with osteoporosis.     

Calcium and vitamin D for osteoprotection in children with new-onset nephrotic syndrome treated with steroids: a prospective,randomized, controlled,interventional study

Background

There are no robust guidelines on strategies to prevent the adverse skeletal effects of glucocorticoids in children.

Objectives

To evaluate the role of prophylactic calcium and vitamin D on bone health in children with new-onset nephrotic syndrome (NS) treated with short-term (12 weeks), high-dose glucocorticoids.

Methods

Prospective, randomized, controlled, single blind, interventional study conducted on 41 steroid-naïve pre-pubertal children (29 boys, 12 girls). All children received prednisolone for 12 weeks (60 mg/m²/day daily for 6 weeks, followed by 40 mg/m²/day alternate days for 6 weeks). Recruited children were randomized into the intervention group (IG; vitamin D 1,000 IU/day and elemental calcium 500 mg/day) and the control group (CG). Bone mineral content (BMC) and bone mineral density (BMD) at the lumbar spine (L1–L4) were estimated at baseline and at 12 weeks. Mean percentage changes in BMC and BMD in IG and CG were compared.

Results

Children in the IG showed an increase of 11.2 % in BMC versus the CG, who showed an 8.9 % fall (p?<?0.0001). Net intervention-attributable difference in BMC was 20.1 %. BMD increased in both groups (IG 2.8 % vs CG 0.74 %), but the difference was not statistically significant (p?=?0.27).

Conclusions

Short-term, high-dose glucocorticoid therapy decreases the BMC of the lumbar spine in steroid-naïve children with NS. Vitamin D and calcium co-administration not only prevents this decline, but also enhances BMC of the lumbar spine.     

Effect of whole body vibration (WBV) therapy on bone density and bone quality in osteopenic girls with adolescent idiopathic scoliosis: a randomized, controlled trial

Summary

The aim of this randomized controlled trial was to determine whether whole body vibration (WBV) therapy was effective for treating osteopenia in adolescent idiopathic scoliosis (AIS) patients. Results showed that WBV was effective for improving areal bone mineral density (aBMD) at the femoral neck of the dominant side and lumbar spine BMC in AIS subjects.

Introduction

AIS is associated with osteopenia. Although WBV was shown to have skeletal anabolic effects in animal studies, its effect on AIS subjects remained unknown. The objective of this study was to determine whether WBV could improve bone mineral density (BMD) and bone quality for osteopenia in AIS subjects.

Methods

This was a randomized, controlled trial recruiting 149 AIS girls between 15 and 25 years old and with bone mineral density (BMD) Z-scores <?1. They were randomly assigned to the Treatment or Control groups. The Treatment group (n?=?61) stood on a low-magnitude high-frequency WBV platform 20 min/day, 5 days/week for 12 months. The Control group (n?=?63) received observation alone. Bone measurement was done at baseline and at 12 months: (1) aBMD and BMC at femoral necks and lumbar spine using dual-energy X-ray absorptiometry (DXA) and (2) bone quality including bone morphometry, volumetric BMD (vBMD), and trabecular bone microarchitecture using high-resolution peripheral quantitative computed tomography (HR-pQCT) for nondominant distal radius and bilateral distal tibiae.

Results

The Treatment group had numerically greater increases in all DXA parameters with a statistically significant difference being detected for the absolute and percentage increases in femoral neck aBMD at the dominant leg (0.015 (SD?=?0.031)g/cm², 2.15 (SD?=?4.32)%) and the absolute increase in lumbar spine BMC (1.17 (SD?=?2.05)g) in the Treatment group as compared with the Control group (0.00084 (SD?=?0.026)g/cm², 0.13 (SD?=?3.62)% and 0.47 (SD?=?1.88)g, respectively). WBV had no significant effect for other bone quality parameters.

Conclusions

WBV was effective for improving aBMD at the femoral neck of the dominant side and lumbar spine BMC in AIS subjects.     

Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women

Summary

We have investigated whether low-dose vitamin K2 supplements (menaquinone-7, MK-7) could beneficially affect bone health. Next to an improved vitamin K status, MK-7 supplementation significantly decreased the age-related decline in bone mineral density and bone strength. Low-dose MK-7 supplements may therefore help postmenopausal women prevent bone loss.

Introduction

Despite contradictory data on vitamin K supplementation and bone health, the European Food Safety Authorities (EFSA) accepted the health claim on vitamin K’s role in maintenance of normal bone. In line with EFSA’s opinion, we showed that 3-year high-dose vitamin K1 (phylloquinone) and K2 (short-chain menaquinone-4) supplementation improved bone health after menopause. Because of the longer half-life and greater potency of the long-chain MK-7, we have extended these investigations by measuring the effect of low-dose MK-7 supplementation on bone health.

Methods

Healthy postmenopausal women (n?=?244) received for 3 years placebo or MK-7 (180 μg MK-7/day) capsules. Bone mineral density of lumbar spine, total hip, and femoral neck was measured by DXA; bone strength indices of the femoral neck were calculated. Vertebral fracture assessment was performed by DXA and used as measure for vertebral fractures. Circulating uncarboxylated osteocalcin (ucOC) and carboxylated OC (cOC) were measured; the ucOC/cOC ratio served as marker of vitamin K status. Measurements occurred at baseline and after 1, 2, and 3 years of treatment.

Results

MK-7 intake significantly improved vitamin K status and decreased the age-related decline in BMC and BMD at the lumbar spine and femoral neck, but not at the total hip. Bone strength was also favorably affected by MK-7. MK-7 significantly decreased the loss in vertebral height of the lower thoracic region at the mid-site of the vertebrae.

Conclusions

MK-7 supplements may help postmenopausal women to prevent bone loss. Whether these results can be extrapolated to other populations, e.g., children and men, needs further investigation.     

Non-linear relationship between serum 25-hydroxyvitamin D concentration and subsequent hip fracture

Summary

Serum 25-OH vitamin D levels were compared in 254 hip fracture subjects and 2,402 matched control subjects. There was a significant inverse association between 25-OH vitamin D and hip fracture only between 0 and 70 nmol/L.

Introduction

Vitamin D is integral to bone metabolism, however the utility of serum 25-OH vitamin D as a risk marker for hip fractures is controversial.

Methods

We conducted a case–control study of patients admitted to the hospitals with hip fractures in Calgary, Alberta, (catchment population 1.4 million) between January 1, 2007 and August 31, 2011. We searched the laboratory information system of Calgary Laboratory Services for serum 25-OH vitamin D levels within 6 months prior to admission on patients admitted to hospital with hip fractures. Cases were identified through the Calgary Laboratory Services laboratory information system and were matched to controls for age, sex, and month of testing. The hip fracture–25-OH vitamin D association was examined using multiple linear and spline regression.

Results

Of 305 subjects initially identified with hip fractures, serum 25-OH vitamin D levels were available for 254 (83 %). These were matched to 2,402 control subjects. We observed a significant (p?<?0.01) non-linear relationship such that 25-OH vitamin D was inversely associated with hip fracture only below 70 nmol/L (odds ratio?=?0.81 per 10 nmol/L increase; 95 % CI 0.86–0.93).

Conclusions

The utility of 25-OH vitamin D level as a risk marker for hip fracture depends on the cut-off level used and was of potential use only for lower levels of 25-OH vitamin D.     

Efficacy and safety of monthly oral minodronate in patients with involutional osteoporosis

Summary

Monthly minodronate at 30 or 50?mg had similar efficacy as 1?mg daily in terms of change in bone mineral density (BMD) and bone turnover markers with similar safety profiles. This new regimen provides patients with a new option for taking minodronate.

Introduction

Minodronate at a daily oral dose of 1?mg has been proven to have antivertebral fracture efficacy. In the present study, the efficacy and safety of oral minodronate at monthly doses of either 30?mg or 50?mg were compared with a daily dose of 1?mg.

Methods

A total of 692 patients with involutional osteoporosis were randomized to receive minodronate at either 30 or 50?mg monthly or a daily dose of 1?mg. The primary endpoint was the percent change from baseline in lumbar spine (LS) BMD at 12?months. Total hip BMD, bone turnover markers, serum calcium (Ca), and parathyroid hormone (PTH) levels were also evaluated.

Results

Minodronate at monthly doses of 30 or 50?mg were noninferior to the 1?mg daily dose in terms of change in LS-BMD. Changes in total hip BMD were also comparable. Although a transient decrease in serum Ca and increase in PTH levels were observed in all three groups at slightly different magnitudes and time courses, changes in bone turnover markers were comparable among the different dosage groups with a similar time course. Safety profiles were also comparable.

Conclusion

Minodronate at monthly doses of 30 or 50?mg has similar efficacy to the daily 1?mg dose in terms of BMD and bone turnover markers with similar tolerability.     

Socioeconomic status and bone health in community-dwelling older men: the CHAMP Study

Summary

The association between socioeconomic status (SES) and bone health, specifically in men, is unclear. Based upon data from the large prospective Concord Health in Ageing Men Project (CHAMP) Study of community-dwelling men aged 70?years or over, we found that specific sub-characteristics of SES, namely, marital status, living circumstances, and acculturation, reflected bone health in older Australian men.

Introduction

Previous studies reported conflicting results regarding the relationship between SES and bone health, specifically in men. The main objective of this study was to investigate associations of SES with bone health in community-dwelling men aged 70?years or over who participated in the baseline phase of the CHAMP Study in Sydney, Australia.

Methods

The Australian Socioeconomic Index 2006 (AUSEI06) based on the Australian and New Zealand Standard Classification of Occupations was used to determine SES in 1,705 men. Bone mineral density and bone mineral content (BMC) were determined by dual-energy X-ray absorptiometry. Bone-related biochemical and hormonal parameters, including markers of bone turnover, parathyroid hormone, and vitamin D, were measured in all men.

Results

General linear models adjusted for age, weight, height, and bone area revealed no significant differences across crude AUSEI06 score quintiles for BMC at any skeletal site or for any of the bone-related biochemical measures. However, multivariate regression models revealed that in Australian-born men, marital status was a predictor of higher lumbar BMC (???=?0.07, p?=?0.002), higher total body BMC (???=?0.05, p?=?0.03), and lower urinary NTX-I levels (??=?0.08, p?=?0.03), while living alone was associated with lower BMC at the lumbar spine (??=?0.05, p?=?0.04) and higher urinary NTX-I levels (??=0.07, p?=?0.04). Marital status was also a predictor of higher total body BMC (???=?0.14, p?=?0.003) in immigrants from Eastern and South Eastern Europe. However, in immigrants from Southern Europe, living alone and acculturation were predictors of higher femoral neck BMC (???=?0.11, p?=?0.03) and lumbar spine BMC (???=?0.10, p?=?0.008), respectively.

Conclusions

Although crude occupation-based SES scores were not significantly associated with bone health in older Australian men, specific sub-characteristics of SES, namely, marital status, living circumstances, and acculturation, were predictors of bone health in both Australia-born men and European immigrants.     

Individual site-specific bone mineral density gain in normocalcemic primary hyperparathyroidism

Summary

In this study, we show that successful parathyroidectomy is followed at 1 year by a significant individual bone mineral density (BMD) gain in nearly half of normocalcemic PHPT patients with reduced bone mass. Alkaline phosphatase levels above median were identified as an independent predictor of individual BMD gain in normocalcemic PHPT patients.

Introduction

The aims of this study were to assess bone mineral density (BMD) gains after parathyroidectomy (PTX) in normocalcemic primary hyperparathyroidism (PHPT) at the individual level and to identify predictors of BMD gain after PTX in this context.

Methods

Longitudinal cohort study of 55 PHPT patients referred for low bone mass and mild abnormalities of calcium/phosphorus metabolism, and successfully treated by PTX. BMD gain at 1 year was considered significant if ≥0.030 g/cm² at one site or more, without any equivalent BMD loss at another site. A logistic regression analysis was performed to identify predictive factors of individual BMD gain.

Results

Among the 55 PHPT patients included, 29 patients with hypercalcemia, 36 patients with normocalcemic PHPT, defined by normal pre-PTX serum total (albumin-corrected) calcium (tCa), including 15 patients with normal ionized calcium (iCa), were identified. At 1 year of PTX, an individual BMD gain was observed in 73.7 % of hypercalcemic, 44.4 % of normocalcemic, and 46 % of PHPT patients with both normal tCa and iCa. Site-specific BMD gains were most important at the spine and hip in all subgroups including patients with normal iCa. Alkaline phosphatase activity above median, which reflects high bone turnover, was predictive of individual BMD gain, both in the overall cohort (OR?=?4.9, 95 % CI 1.3–18.9), and in the normocalcemic group: OR?=?8.4, 95 % CI 1.4–56.6.

Conclusions

Successful PTX is followed at 1 year by a significant individual BMD gain in nearly half of normocalcemic PHPT patients with osteoporosis. ALP levels above median could contribute to the therapeutic decision in this context.     

Automated 3D trabecular bone structure analysis of the proximal femur—prediction of biomechanical strength by CT and DXA

Summary

The standard diagnostic technique for assessing osteoporosis is dual X-ray absorptiometry (DXA) measuring bone mass parameters. In this study, a combination of DXA and trabecular structure parameters (acquired by computed tomography [CT]) most accurately predicted the biomechanical strength of the proximal femur and allowed for a better prediction than DXA alone.

Introduction

An automated 3D segmentation algorithm was applied to determine specific structure parameters of the trabecular bone in CT images of the proximal femur. This was done to evaluate the ability of these parameters for predicting biomechanical femoral bone strength in comparison with bone mineral content (BMC) and bone mineral density (BMD) acquired by DXA as standard diagnostic technique.

Methods

One hundred eighty-seven proximal femur specimens were harvested from formalin-fixed human cadavers. BMC and BMD were determined by DXA. Structure parameters of the trabecular bone (i.e., morphometry, fuzzy logic, Minkowski functionals, and the scaling index method [SIM]) were computed from CT images. Absolute femoral bone strength was assessed with a biomechanical side-impact test measuring failure load (FL). Adjusted FL parameters for appraisal of relative bone strength were calculated by dividing FL by influencing variables such as body height, weight, or femoral head diameter.

Results

The best single parameter predicting FL and adjusted FL parameters was apparent trabecular separation (morphometry) or DXA-derived BMC or BMD with correlations up to r?=?0.802. In combination with DXA, structure parameters (most notably the SIM and morphometry) added in linear regression models significant information in predicting FL and all adjusted FL parameters (up to R _adj?=?0.872) and allowed for a significant better prediction than DXA alone.

Conclusion

A combination of bone mass (DXA) and structure parameters of the trabecular bone (linear and nonlinear, global and local) most accurately predicted absolute and relative femoral bone strength.