Assessment of Fat distribution and Bone quality with Trabecular Bone Score (TBS) in Healthy Chinese Men

Areal bone mineral density, trabecular bone score and 3D-DXA analysis of proximal femur in psoriatic disease

Objectives

To evaluate bone mineral density (BMD) and bone quality, with assessment of the cortical and trabecular compartments, in patients with psoriasis (PsO) alone or with psoriatic arthritis (PsA).

Methods

Patients with PsA and patients with PsO alone were evaluated and compared to control subjects matched for age, sex and body mass index category. Areal BMD (aBMD) was determined for the lumbar spine, femoral neck, total hip and total body using dual-energy X-ray absorptiometry (DXA). Bone quality was evaluated by using trabecular bone score (TBS) at the lumbar spine, and by 3D DXA-based analysis (3D Shaper) for the proximal femur.

Results

One hundred ninety-six subjects including 52 patients with PsA and 52 patients with PsO and their respective paired controls were analyzed. Patients with PsA had comparable aBMD, TBS and 3D DXA analysis parameters compared to their paired controls. After adjustment for confounders, patients with PsO alone were characterized by a higher aBMD at the left femur and higher cortical 3D DXA derived parameters (total hip cortical surface BMD and total hip cortical thickness) than their paired controls. TBS was decreased in PsO compared to their controls.

Conclusion

Patients with PsA had normal bone mass and bone quality parameters. Patients with PsO were characterized by higher femoral neck bone density by DXA and cortical parameters by 3D DXA-based analysis, supporting no increased risk for hip fracture. Conversely, bone texture by TBS assessment was decreased in patients with PsO, which may be associated with impaired vertebral bone resistance.

Obesity and Skeletal Fragility

Skeletal fracture has recently emerged as a complication of obesity. Given the normal or better than normal bone mineral density (BMD), the skeletal fragility of these patients appears to be a problem of bone quality rather than quantity. Type 2 diabetes mellitus (T2DM), the incidence of which increases with increasing body mass index, is also associated with an increased risk for fractures despite a normal or high BMD. With the additional bone pathology from diabetes itself, patients with both obesity and T2DM could have a worse skeletal profile. Clinically, however, there are no available methods for identifying those who are at higher risk for fractures or preventing fractures in this subgroup of patients. Weight loss, which is the cornerstone in the management of obesity (with or without T2DM), is also associated with an increased risk of bone loss. This review of the literature will focus on the skeletal manifestations associated with obesity, its interrelationship with the bone defects associated with T2DM, and the available approach to the bone health of patients suffering from obesity.

Clinical Use of Trabecular Bone Score: The 2023 ISCD Official Positions

Osteoporosis can currently be diagnosed by applying the WHO classification to bone mineral density (BMD) assessed by dual-energy x-ray absorptiometry (DXA). However, skeletal factors other than BMD contribute to bone strength and fracture risk. Lumbar spine TBS, a grey-level texture measure which is derived from DXA images has been extensively studied, enhances fracture prediction independent of BMD and can be used to adjust fracture probability from FRAX® to improve risk stratification. The purpose of this International Society for Clinical Densitometry task force was to review the existing evidence and develop recommendations to assist clinicians regarding when and how to perform, report and utilize TBS. Our review concluded that TBS is most likely to alter clinical management in patients aged ≥ 40 years who are close to the pharmacologic intervention threshold by FRAX. The TBS value from L1-L4 vertebral levels, without vertebral exclusions, should be used to calculate adjusted FRAX probabilities. L1-L4 vertebral levels can be used in the presence of degenerative changes and lumbar compression fractures. It is recommended not to report TBS if extreme structural or pathological artifacts are present. Monitoring and reporting TBS change is unlikely to be helpful with the current version of the TBS algorithm. The next version of TBS software will include an adjustment based upon directly measured tissue thickness. This is expected to improve performance and address some of the technical factors that affect the current algorithm which may require modifications to these Official Positions as experience is acquired with this new algorithm.

Age, body composition parameters and glycaemic control contribute to trabecular bone score deterioration in acromegaly more than disease activity

Introduction

Impairment of bone structure in patients with acromegaly (AP) varies independently of bone mineral density (BMD). Body composition parameters, which are altered in patients with acromegaly, are important determinants of bone strength.

Purpose

The aim of this study was to examine BMD and lumbar trabecular bone score (TBS) by dual-energy X-ray absorptiometry (DXA) and to assess its relationship with disease activity, age, glucose metabolism, and body composition parameters.

Methods

This cross-sectional prospective study involved 115 patients with acromegaly (70 F, 45 M) and 78 healthy controls (CON) (53 F, 25 M) matched for age, gender, and BMI. Bone mineral density, TBS and body composition parameters were measured using DXA.

Results

AP presented with lower TBS compared to CON (1.2 ± 0.1 v 1.31 ± 0.1, P< 0.001). No significant correlation was observed between IGF-1/GH levels and TBS. Age, glycated haemoglobin, BMI, waist circumference, fat mass, and lean mass negatively correlated with TBS in both sexes. Multiple linear regression analysis of all these parameters revealed age and waist circumference as independent significant predictors of TBS in AP. We did not find difference in BMD (lumbar and femoral sites) between AP and CON nor between active and controlled AP. We observed negative correlation between age and BMD of the femoral neck and total hip (P < 0.001). Testosterone levels in males, BMI, waist circumference, fat mass, and lean mass positively correlated with BMD in AP, with stronger correlation between lean mass and BMD compared to fat mass.

Conclusion

Patients with acromegaly have lower TBS than controls, confirming impaired bone microarchitecture in acromegaly regardless of BMD. Age, body composition parameters and glucose metabolism contribute to TBS deterioration in AP more than disease activity itself.

Added value of waist circumference to body mass index for predicting fracture risk in obesity: a prospective study from the CARTaGENE cohort

Larger waist circumference is significantly associated with an increased risk of distal lower limb fractures in individuals aged 40-70 years with a body mass index within the normal or overweight category. Therefore, waist circumference provides additive information to body mass index for the identification of individuals at risk of obesity-related fractures.

INTRODUCTION

Waist circumference (WC) is a stronger risk factor of metabolic disorders than body mass index (BMI), but whether it holds true for fracture risk prediction remains unclear. We aimed to evaluate relationships between WC and fracture incidence within BMI categories and evaluate whether BMI modifies these relationships.

METHODS

Men and women aged 40-70 years from the CARTaGENE cohort were divided by BMI category at baseline: normal weight, overweight, and obesity. Incident fractures were identified over 7 years via linkage with healthcare administrative databases. Cox proportional hazard models estimated the relationships between WC and incident fractures at any site and by skeletal site within each BMI category. Results are reported as adjusted hazard ratios (95% confidence intervals) per 10 cm increase in WC. Effect modification was evaluated qualitatively by comparing relationships between BMI categories.

RESULTS

Of the 18 236 individuals included, 754 sustained a fracture. Significant relationships were found between WC and distal lower limb fractures in the normal (1.25 [1.08, 1.45]) and overweight (1.28 [1.07, 1.52]) BMI categories, but not in the obesity category. In the overweight category, we found an increased risk of distal upper limb fractures with increasing WC (1.49 [1.04, 2.15]). No significant relationship was observed regarding WC and fracture risk at any site or major osteoporotic fractures. An effect modification of BMI on the relationships between WC and distal lower limb fractures was observed.

CONCLUSION

WC provides both independent and additive information to BMI for the identification of individuals at risk of obesity-related fractures.

The effect of body size and composition on lumbar spine trabecular bone score in morphologically diverse subjects

AIM

The trabecular bone score (TBS) is a tool for assessing bone quality and health. Current TBS algorithm corrects for body mass index (BMI), as a proxy of regional tissue thickness. However, this approach fails to consider BMI inaccuracies due to individual differences in body stature, composition and somatotype. This study investigated the relationship between TBS and body size and composition in subjects with a normal BMI, but with large morphological diversity in body fatness and height.

METHODS

Young male subjects (n = 97; age 17.2±1.0 years), including ski jumpers (n = 25), volleyball players (n = 48) and non-athletes (controls n = 39), were recruited. The TBS was determined from L1-L4 dual-energy X-ray absorptiometry (DXA) scans using TBSiNsight software.

RESULTS

TBS correlated negatively with height and tissue thickness in the L1-L4 area in ski jumpers (r = -0.516 and r = -0.529), volleyball players (r = -0.525 and r = -0.436), and the total group (r = -0.559 and r = -0.463), respectively. Multiple regression analyses revealed that height, L1-L4 soft tissue thickness, fat mass and muscle mass were significant determinants of TBS (R2 = 0.587, p<0.001). L1-L4 soft tissue thickness explained 27% and height 14% of the TBS variance.

CONCLUSION

The negative association of TBS and both features suggests that a very low L1-L4 tissue thickness may lead to overestimation of the TBS, while tall stature may have the opposite effect. It seems that the utility of the TBS as a skeletal assessment tool in lean and/or tall young male subjects could be improved if tissues thickness in the lumbar spine area and stature instead of BMI were considered in the algorithm.

Gender-specific impacts of thigh skinfold thickness and grip strength for predicting osteoporosis in type 2 diabetes

BACKGROUND

Diabetes with co-existing bone fragility or osteoporosis is common in elderly patients, whereas is frequently underestimated.

METHODS

We conducted dual-energy x-ray absorptiometry (DXA) with 7-site skinfold (SF) and dominant hand grip strength measurements among patients with type 2 diabetes (T2DM) to assess their gender-specific associations. A total of 103 patients with T2DM (60 females and 43 males), aged between 50 and 80 years (median 68.0 years) were enrolled and 45 non-DM females were also included to compare with T2DM females.

RESULTS

Our results revealed osteoporosis was negatively correlated with grip strength in both genders, negatively correlated with lean mass solely in males and negatively correlated with fat mass (particular the gynoid fat mass and thigh SF thickness) in females. Via performing multivariable stepwise logistic regression, we identified grip strength in both genders and thigh SF thickness in females as predictors for osteoporosis. Receiver operating characteristic curve analysis further disclosed 20.5 mm female thigh skinfold thickness, 18.1 kg female grip strength and 29.0 kg male grip strength as reasonable cutoff levels for predicting osteoporosis in the Taiwanese patients with T2DM.

CONCLUSIONS

Patients with T2DM presented gender-specific associations between osteoporosis, body composition and grip strength. Grip strength and thigh SF thickness might serve as predictors for detection of osteoporosis in patients with T2DM.

Body composition, trabecular bone score and vertebral fractures in subjects with Klinefelter syndrome

BACKGROUND

Klinefelter syndrome (KS) frequently causes skeletal fragility characterized by profound alterations in bone microstructure with increased risk of fractures. Increased body fat mass associated with decreased body lean mass are frequent features of KS with possible detrimental effects on skeletal health. In this cross-sectional study, we evaluated the associations between body composition parameters, vertebral fractures (VFs) and trabecular bone score (TBS) in adult subjects with KS.

METHODS

Seventy-one adult males (median age 41 years, range 18-64) with 47, XXY KS were consecutively enrolled by two Endocrinology and Andrology Units (IRCCS Humanitas Research Hospital in Milan and ASST Spedali Civili in Brescia). Dual-energy X-ray absorptiometry (DXA) was performed to assess bone mineral density (BMD) at lumbar spine, femoral neck and total hip, TBS and body composition. Prevalence of VFs was assessed by quantitative morphometry on lateral spine X-rays.

RESULTS

VFs were detected in 14 patients (19.7%), without significant association with low BMD (p = 0.912). In univariate logistic regression analysis, VFs were significantly associated with truncal/leg fat ratio (OR 2.32 per tertile; 95% CI 1.05-5.15; p = 0.038), whereas impaired TBS (detected in 23.4% of subjects) was associated with older age at study entry (p = 0.001) and at diagnosis of disease (p = 0.015), body mass index (BMI; p = 0.001), waist circumference (p = 0.007), fat mass index (FMI; p < 0.001), FMI/lean mass index (LMI) ratio (p = 0.001). Prevalence of VFs was not significantly different between subjects with impaired TBS as compared to those with normal TBS (26.7 vs. 18.4%; p = 0.485). Skeletal end-points were not significantly associated with duration of testosterone replacement therapy and serum testosterone and 25hydroxyvitamin D values.

CONCLUSION

Body composition might influence bone quality and risk of VFs in subjects with KS.

Factors associated with trabecular bone score in postmenopausal women with type 2 diabetes and normal bone mineral density

BACKGROUND

Osteoporosis and type 2 diabetes (T2D) have been recognized as a widespread comorbidity leading to excess mortality and an enormous healthcare burden. In T2D, bone mineral density (BMD) may underestimate the risk of low-energy fractures as bone quality is reduced. It was hypothesized that a decrease in the trabecular bone score (TBS), a parameter assessing bone microarchitecture, may be an early marker of impaired bone health in women with T2D.

AIM

To identify clinical and body composition parameters that affect TBS in postmenopausal women with T2D and normal BMD.

METHODS

A non-interventional cross-sectional comparative study was conducted. Potentially eligible subjects were screened at tertiary referral center. Postmenopausal women with T2D, aged 50-75 years, with no established risk factors for secondary osteoporosis, were included. BMD, TBS and body composition parameters were assessed by dual-energy X-ray absorptiometry. In women with normal BMD, a wide range of anthropometric, general and diabetes-related clinical and laboratory parameters were evaluated as risk factors for TBS decrease using univariate and multivariate regression analysis and analysis of receiver operating characteristic (ROC) curves.

RESULTS

Three hundred twelve women were initially screened, 176 of them met the inclusion criteria and underwent dual X-ray absorptiometry. Those with reduced BMD were subsequently excluded; 96 women with normal BMD were included in final analysis. Among them, 43 women (44.8%) showed decreased TBS values (≤ 1.31). Women with TBS ≤ 1.31 were taller and had a lower body mass index (BMI) when compared to those with normal TBS (Р = 0.008 and P = 0.007 respectively). No significant differences in HbA1c, renal function, calcium, phosphorus, alkaline phosphatase, PTH and 25(ОН)D levels were found. In a model of multivariate linear regression analysis, TBS was positively associated with gynoid fat mass, whereas the height and androgen fat mass were associated negatively (all P < 0.001). In a multiple logistic regression, TBS ≤ 1.31 was associated with lower gynoid fat mass (adjusted odd ratio [OR], 0.9, 95% confidence interval [CI], 0.85-0.94, P < 0.001), higher android fat mass (adjusted OR, 1.13, 95%CI, 1.03-1.24, P = 0.008) and height (adjusted OR, 1.13, 95%CI, 1.05-1.20, P < 0.001). In ROC-curve analysis, height ≥ 162.5 cm (P = 0.04), body mass index ≤ 33.85 kg/m² (P = 0.002), gynoid fat mass ≤ 5.41 kg (P = 0.03) and android/gynoid fat mass ratio ≥ 1.145 (P < 0.001) were identified as the risk factors for TBS reduction.

CONCLUSION

In postmenopausal women with T2D and normal BMD, greater height and central adiposity are associated with impaired bone microarchitecture.

The association between body fat distribution and bone mineral density: evidence from the US population

OBJECTIVE

To investigate the association between different body fat distribution and different sites of BMD in male and female populations.

METHODS

Use the National Health and Nutrition Examination Survey (NHANES) datasets to select participants. The weighted linear regression model investigated the difference in body fat and Bone Mineral Density (BMD) in different gender. Multivariate adjusted smoothing curve-fitting and multiple linear regression models were used to explore whether an association existed between body fat distribution and BMD. Last, a subgroup analysis was performed according to age and gender group.

RESULTS

Overall, 2881 participants were included in this study. Compared to males, female participants had lower BMD (P < 0.05) and higher Gynoid fat mass (P < 0.00001), while there was no difference between Android fat mass (P = 0.91). Android fat mass was positively associated with Total femur BMD (Males, β = 0.044, 95% CI = 0.037, 0.051, P < 0.00001; Females, β = 0.044, 95% CI = 0.039, 0.049, P < 0.00001), Femoral neck BMD (Males, β = 0.034, 95% CI = 0.027, 0.041, P < 0.00001; Females, β = 0.032, 95% CI = 0.027, 0.037, P < 0.00001), and Total spine BMD (Males, β = 0.036, 95% CI = 0.029, 0.044, P < 0.00001; Females, β = 0.025, 95% CI = 0.019, 0.031, P < 0.00001). The Gynoid fat mass, subgroup analysis of age and ethnicity reached similar results.

CONCLUSION

Body fat in different regions was positively associated with BMD in different sites, and this association persisted in subgroup analyses across age and race in different gender.

Body Composition as a Modulator of Bone Health Changes in Patients with Inflammatory Bowel Disease

Background: Bone impairment of multifactorial etiology is a common feature in inflammatory bowel disease (IBD). Body composition parameters, which might be selectively modified in these patients, are important determinants of bone strength. Our aim was to investigate the relationship between components of body composition and bone parameters in IBD patients. Methods: This is a cross-sectional, retrospective study including 80 IBD patients (43 women, 37 men). Lumbar spine (LS), femoral neck (FN) and whole body DXA scans were performed to analyze regional bone mineral density (BMD), as well as body composition, including appendicular skeletal muscle mass index (ASMI), total and visceral fat mass (VAT). Trabecular bone score (TBS) was assessed using iNsight Software. Results: Twenty (25%) IBD patients had inadequate LS-BMD z scores (<=−2DS). Lean mass (LM) was a significant determinant of LS-BMD, after adjusting for age, gender, BMI and fat mass (p < 0.01), while fat mass% remained associated with FN-BMD (p < 0.01). TBS correlated positively with BMI (r = 0.24, p < 0.05), LS-BMD (r = 0.56, p < 0.001), ASMI (r = 0.34, p < 0.001) and negatively with VAT/total fat% (r = −0.27, p < 0.05). Multivariate analysis showed that ASMI, LS-BMD (positively) and VAT/total fat% (negatively) were independently associated with TBS. Conclusions: In IBD patients, skeletal muscle mass and fat percentage and distribution are important factors associated with bone health.

Lower trabecular bone score in type 2 diabetes mellitus: A role for fat mass and insulin resistance beyond hyperglycaemia

AIMS

To examine the clinical and biochemical determinants of trabecular bone score (TBS) in type 2 diabetes mellitus (T2DM) patients.

METHODS

Cross-sectional observational study in 137 T2DM patients (49-85 years). Whole-body fat percentage was estimated using the relative fat mass (RFM) equation. Bone mineral density (BMD) and TBS were assessed using dual-energy X-ray absorptiometry and TBS iNsight Software respectively.

RESULTS

T2DM patients showed significantly lower TBS values (P < 0.001) despite significantly higher lumbar spine BMD (LS-BMD) (P = 0.025) compared to controls. TBS values ​​were negatively correlated with body mass index (BMI) (P < 0.001), waist circumference (P < 0.001), and HOMA-2IR index (P = 0.004) and positively correlated with sex hormone-binding globulin (SHBG) (P = 0.01) and LS-BMD (P = 0.003). RFM was negatively associated with TBS in both males (P < 0.001) and females (P = 0.005). The multivariate analysis showed that RFM, HOMA2-IR (negative), SHBG, and LS-BMD (positive) were the variables independently associated with TBS. ROC analysis revealed RFM as the variable with the highest predictive value for risk of degraded bone microarchitecture.

CONCLUSIONS

The adiposity estimated by RFM may negatively affect TBS and this relationship may be influenced by insulin resistance and SHBG. RFM could act as a key estimator of degraded bone microarchitecture risk in the T2DM population.

Effect of metformin and insulin vs. placebo and insulin on whole body composition in overweight patients with type 2 diabetes: a randomized placebo-controlled trial

Some studies indicate potential beneficial effects of metformin on body composition and bone. This trial compared metformin + insulin vs placebo + insulin. Metformin treatment had a small but positive effect on bone quality in the peripheral skeleton, reduced weight gain, and resulted in a more beneficial body composition compared with placebo in insulin-treated patients with type 2 diabetes.

INTRODUCTION

Glucose-lowering medications affect body composition. We assessed the long-term effects of metformin compared with placebo on whole body bone and body composition measures in patients with type 2 diabetes mellitus.

METHODS

This was a sub-study of the Copenhagen Insulin and Metformin Therapy trial, which was a double-blinded randomized placebo-controlled trial assessing 18-month treatment with metformin compared with placebo, in combination with different insulin regimens in patients with type 2 diabetes mellitus (T2DM). The sub-study evaluates the effects on bone mineral content (BMC), density (BMD), and body composition from whole body dual-energy X-ray absorptiometry (DXA) scans which were assessed at baseline and after 18 months.

RESULTS

Metformin had a small, but positive, (p < 0.05) effect on subtotal, appendicular, and legs BMC and BMD compared with placebo. After adjustment for sex, age, vitamin D, smoking, BMI, T2DM duration, HbA1c, and insulin dose, the effects on appendicular BMC and BMD persisted (p < 0.05 for both). The changes in appendicular BMC and BMD corresponded approximately to a 0.7% and 0.5% increase in the metformin group and 0.4% and 0.4% decrease in the placebo group, respectively. These effects were mostly driven by an increase in BMC and BMD in the legs and a loss of BMC and BMD in the arms. During 18 months, all participants increased in weight, fat mass (FM), FM%, and lean mass (LM), but decreased in LM%. The metformin group increased less in weight (subtotal weight (weight-head) - 2.4 [- 3.5, - 1.4] kg, p value < 0.001) and FM (- 1.5 [- 2.3, - 0.8] kg, p value < 0.001) and decreased less in LM% (0.6 [0.2, 1.1] %, p value < 0.001) compared with the placebo group.

CONCLUSION

Metformin treatment had a small positive effect on BMC and BMD in the peripheral skeleton and reduced weight gain compared with placebo in insulin-treated patients with T2DM.

Factors associated with TBS worse than BMD in non-osteoporotic elderly population: Bushehr elderly health program

BACKGROUND

Bone mineral density (BMD) and trabecular bone score (TBS) are moderately correlated. TBS is sometimes used as an adjuvant to BMD in the fracture risk assessment. Some individuals with normal BMD or osteopenia, have more degraded TBS. We aimed to identify factors associated with TBS worse than BMD in the non-osteoporotic elderly population.

METHODS

The study subjects were selected from 2384 women and men aged ≥60 years participating in the second stage of the Bushehr Elderly Health program, a population-based prospective cohort study in Iran. The BMDs of different sites and the lumbar spine texture were measured using dual-energy X-ray absorptiometry and the TBS algorithm, respectively. Subjects were categorized based on their BMD and TBS status. Logistic regression was performed to identify the factors associated with "TBS worse than BMD" in non-osteoporotic individuals.

RESULTS

Of 1335 participants included in the study, 112 of 457 women, and 54 of 878 men had worse TBS than BMD. In multivariable analysis, TBS worse than BMD in women was statistically significantly associated with years since menopause (OR: 1.04 (1.00-1.07)) and waist circumference (OR: 1.09 (1.05-1.14)). However, in men, the condition was statistically significantly associated with waist circumference (OR: 1.10 (1.03-1.17)), current smoking (OR: 2.54 (1.10-5.84)), and HDL-C (OR: 1.03 (1.00-1.06)).

CONCLUSION

The results of the study show that higher waist circumference is associated with more degraded TBS than BMD in both men and women. Years passed since menopause and current smoking, respectively in women and men, were associated with more degraded TBS. Considering TBS values in older individuals with higher waist circumference, or a history of smoking despite normal BMDs might help more accurate assessment of bone health. However, further studies are required to confirm the benefit.

Bone characteristics and metabolic phenotypes of obesity in an Iranian Elderly population: Bushehr Elderly Health Program (BEHP)

INTRODUCTION

Obesity and osteoporosis are health problems with high impact on the morbidity and mortality rate. While the association between BMI and bone density is known, the combined effects of obesity and metabolic components on bone health have not yet been revealed. The objectives of this study were to determine the association between bone health and different phenotypes of obesity in an elderly population.

METHODS

This cross-sectional study was conducted on the data collected in the Bushehr Elderly Health Program (BEHP). The participants were classified in four groups based on the metabolic phenotypes of obesity (metabolic healthy obese (MHO), metabolic non-healthy non-obese (MNHNO), metabolic non-healthy obese (MNHO), and metabolic healthy non-obese (MHNO)). The association between osteoporosis and TBS and the metabolic phenotypes of obesity were assessed using multiple variable logistic regression models.

RESULTS

Totally, 2378 people (1227 women) were considered for analyses. The prevalence of MHNO, MHO, MNHNO, and MNHO were 902 (39.9%), 138 (6.1%), 758 (33.5%), and 464 (20.5%), respectively. In the multivariate logistic regression models, those with MHO (OR 0.22; 95% CI 0.12-0.36), MNHNO (OR 0.52; 95% CI 0.4-0.66), and MNHO phenotypes (OR 0.22; 95% CI 0.16-0.3) had a significantly lower risk of osteoporosis. Likewise, those having MHO (OR 2.38; 95% CI 1.51-3.76), MNHNO (OR 1.49; 95% CI 1.11-2), and MNHO (OR 2.50; 95% CI 1.82-3.42) phenotypes were found to had higher risk of low bone quality as confirmed by TBS.

CONCLUSIONS

The obese subjects have lower bone quality, regardless of their obesity phenotype.

Changes in spinal bone density, back muscle size, and visceral adipose tissue and their interaction following a multi-component exercise program in older men: secondary analysis of an 18-month randomized controlled trial

In middle-aged and older men, an 18-month multi-component exercise program improved spinal trabecular BMD, paraspinal, and psoas muscle cross-sectional area (CSA) but not visceral adipose tissue (VAT). However, changes in both muscle and VAT CSA were associated with changes in spinal BMD, independent of the exercise intervention.

INTRODUCTION

In older men, we previously reported that a multi-component exercise program improved lumbar spine (LS) trabecular volumetric BMD (Tb.vBMD) compared with no exercise. This study aimed to investigate the following: (1) the effect of the exercise program on paraspinal and psoas (back) muscle CSA and VAT, and 2) if any exercise-related changes in muscle CSA and/or VAT were associated with changes in spinal BMD.

METHODS

Men (n = 180) aged 50-79 years were randomized to an exercise or no-exercise group. Exercise involved high-intensity progressive resistance training (60-85% max) with weight-bearing impact exercise (3 days/week) for 18 months. Quantitative computed tomography was used to assess L1-L3 Tb.vBMD, paraspinal, and psoas muscle CSA and VAT.

RESULTS

Exercise resulted in a 2.6% ((95% CI, 1.1, 4.1), P < 0.01) net gain in back muscle CSA, but no effect on VAT (-1.6% (95% CI, -7.3, 4.2)) relative to no exercise. Robust regression indicated that percentage changes in Tb.vBMD were positively associated with changes (expressed as z-scores) in back muscle CSA in both the exercise (beta (β)-coefficient = 1.9, 95% CI 0.5, 3.2, P = 0.007) and no-exercise (β = 2.6, 95% CI, 1.1, 4.1, P = 0.001) group, and negatively with the changes in VAT (β = -2.0, 95% CI -3.3, -0.7, P = 0.003) in the exercise only group. There were no group differences in the slopes for the muscle-bone or VAT-bone relationships. Regression analysis (pooled data) revealed that back muscle CSA and VAT were independent predictors of the change in Tb.vBMD, explaining 14% of the variance.

CONCLUSION

A multi-component exercise program in middle-aged and older men improved spinal BMD and back muscle size but not visceral fat. However, changes in back muscle size and VAT were associated with the changes in spinal BMD, independent of exercise.

TRIAL REGISTRATION

ACTRN 12617001224314, 22/08/2017 retrospectively registered.

Reduction of visceral fat could be related to the improvement of TBS in diabetes mellitus

INTRODUCTION

Diabetes has been proposed as a risk factor for increased skeletal fragility. Visceral fat is known to yield adverse effects on bone metabolism in people with diabetes. We investigated the relationship between the change in visceral fat mass over time and TBS or BMD.

MATERIALS AND METHODS

This retrospective study enrolled 690 (male: 367; female: 323) subjects with type 2 diabetes mellitus. Visceral fat mass, lumbar and femoral neck BMD, and lumbar spine TBS were measured via dual-energy X-ray absorptiometry (DXA), including the follow-up data within a 3-year period.

RESULTS

TBS significantly increased as visceral fat mass decreased in both sexes (p < 0.001), whereas lumbar BMD and femoral neck BMD showed meaningful changes only in men. The multiple regression model with adjustment for age, weight, creatinine level, lipid profile, HbA1C, and status of osteoporosis medication use revealed that TBS and femoral neck BMD were correlated with visceral fat mass. However, regarding longitudinal changes, only the change in visceral fat mass had a significant relationship with TBS (males: β = - 0.298, p < 0.001; females: β = - 0.216, p < 0.001).

CONCLUSIONS

The results of this study may suggest the beneficial effect of controlling visceral fat mass on bone health in type 2 diabetes patients. Besides, DXA-derived TBS could be a useful diagnostic tool for evaluating the bone changes according to metabolic changes in type 2 diabetes, which are not entirely achieved with BMD.

Fat distribution may predict intra- or extra-capsular hip fracture in geriatric patients after falling

INTRODUCTION

Hip fractures can be divided into intra-capsular and extra-capsular fracture based on fracture location; these two types of fracture have different pathogeneses, treatments and prognoses. Many factors influence the patterns of hip fractures, including the injury mechanism, areal bone mineral density and the geometry of the hip. However, the relationship between body composition and hip fracture pattern has not yet been discussed. In this investigation, an analysis of the body compositions of geriatric patients with hip fractures were conducted to identify differences between fat and muscle distributions between patients with intra- and extra-capsular hip fractures.

MATERIAL AND METHODS

From December 2017 to February 2019, 139 patients with a hip fracture were prospectively enrolled in this study. The groups of patients that were diagnosed as having intra- and extra-capsular hip fractures were compared in terms of patient demographics, pre-operative laboratory data, bone mineral density (BMD) and body composition including muscle and fat distributions obtained using dual-energy X-ray absorptiometry (DXA) .

RESULTS

Eighty-six and 53 patients were diagnosed with intra-capsular and extra-capsular hip fractures, respectively. A significantly higher serum glucose level, a lower hemoglobin level, a lower T-score level in the proximal femur region, a lower T-score of all parts of interest, and a lower percentage fat content on the region of bilateral proximal hips (gynoid region) and in the lower limb region, were observed in patients with an extra-capsular hip fracture than in those with an intra-capsular hip fracture. However, with all confounding factors controlled for, only the T-score at the proximal femur, percentage fat content in the region of bilateral proximal hips and the ratio of android fat content to gynoid fat content (A/G ratio) are the most relevant factors in predicting the patterns of hip fracture in geriatric patients after falling.

CONCLUSION

This work demonstrates that lower fat content in the region of bilateral proximal hips and a lower BMD on the proximal femur may predict greater vulnerability of geriatric patients to extra-capsular rather than intra-capsular hip fracture after a falling accident.

Relationship of Two-Hour Plasma Glucose and Abdominal Visceral Fat with Bone Mineral Density and Bone Mineral Content in Women with Different Glucose Metabolism Status

BACKGROUND

Several studies have reported the relationship of diabetes mellitus (DM) and obesity with bone mineral density (BMD), but the conclusions remain unclear. This study aimed to provide more information for the relationship of plasma glucose and abdominal visceral fat (AVF) with BMD and bone mineral content (BMC) in women with different glucose metabolism status.

METHODS

Patients were screened by oral glucose tolerance test (OGTT) and were divided into three groups: normal glucose tolerance (NGT, n=132), pre-diabetes mellitus (pre-DM, n=28) and newly diagnosed type 2 DM (T2DM, n=27) groups. Plasma glucose concentrations, anthropometric measurements, body composition, and BMD were measured. Analysis of variance (ANOVA), pearson correlation, and multiple linear regression models were used to evaluate the relationship between BMD, plasma glucose, AVF, and other variables.

RESULTS

The percentage of subjects with osteoporosis or low BMD was 29.9%, and 66.7% subjects in T2DM group were significantly higher than that in the pre-DM (28.6%) and NGT (22.7%) groups (p=0.005 and p<0.001, respectively). Both BMD at femoral neck (FN) and lumbar spine (LS) of T2DM group were lower than those in NGT group (p=0.009 and p=0.003, respectively), and BMC of T2DM group was lower than those of NGT and pre-DM groups (p<0.001). The results of statistical analysis revealed that both two-hour plasma glucose (2-h PG) and age showed negative correlation with BMC, FN BMD, and LS BMD. AVF showed positive correlation with BMC and LS BMD. Furthermore, the lean mass (LM) showed independent positive effects on BMC.

CONCLUSION

Our findings suggest that 1) Age is a strong negative predictor of bone mass. 2) A direct negative effect of increasing 2-h PG might be more prominent at bone mass in women. 3) A moderate increase in AVF is beneficial to bone mass, while excessive increase might be harmful. 4) LM is a positive predictor of BMC.

Trabecular Bone Score in Obese and Nonobese Subjects With Primary Hyperparathyroidism Before and After Parathyroidectomy

CONTEXT

Obesity has been shown to be unfavorable to skeletal microarchitecture when assessed by trabecular bone score (TBS). The influence of adiposity on skeletal microstructure in primary hyperparathyroidism (PHPT) has not yet been evaluated.

OBJECTIVE

To investigate the effect of obesity on TBS and bone mineral density (BMD) in subjects with PHPT at baseline and through 2 years after parathyroidectomy.

DESIGN

Prospective observational study.

SETTING

Referral center.

PATIENTS OR OTHER PARTICIPANTS

Thirty men and women with PHPT undergoing parathyroid surgery.

MAIN OUTCOME MEASURES

TBS and BMD by dual-energy X-ray absorptiometry (DXA).

RESULTS

There were notable improvements in lumbar spine and femoral neck BMD in the obese (lumbar spine: 4.3 ± 4.7%, femoral neck: 3.8 ± 6.6%; P < 0.05 for both) and nonobese subjects (lumbar spine: 3.8 ± 5.6%, femoral neck 3.1 ± 5.0%; P < 0.05 for both) but no marked change in TBS in either group at 24 months postparathyroidectomy. Obese subjects had fully degraded TBS values compared with the nonobese subjects, whose TBS values were minimally below normal throughout the study (baseline: 1.199 ± 0.086 vs 1.327 ± 0.099, respectively; P = 0.003; 24 months: 1.181 ± 0.061 vs 1.352 ± 0.114, respectively; P = 0.001), despite improvements in BMD.

CONCLUSIONS

The detrimental effect of obesity on TBS, an index of bone quality, was demonstrated in subjects with PHPT. Obesity was associated with fully degraded skeletal microarchitecture as measured by TBS in PHPT, despite similar values in bone density by DXA compared with nonobese subjects. TBS values did not improve postparathyroidectomy in either obese or nonobese subjects.

The correlation between bone mineral density/trabecular bone score and body mass index, height, and weight

OBJECTIVES

This study investigated the correlation between bone mineral density (BMD)/trabecular bone score (TBS) and body mass index (BMI), height and weight in Korean adults.

METHODS

We enrolled 2555 female participants in their 20s-80s and 1631 male participants in their 20s-70s. Participants with history of previous vertebral surgeries or current vertebral diseases were excluded. Female and male participants were divided into osteoporosis group (n = 136 and n = 31, respectively), osteopenia group (n = 822 and n = 460, respectively), and normal group (n = 1596 and n = 1140, respectively) based on their BMD T-score. Dual-energy X-ray absorptiometry image analysis and linear regression analysis were conducted on each participant in each group to determine the P-value and the correlation between BMD T-score/TBS T-score and BMI, weight, and height.

RESULTS

We found a significant correlation between BMI and TBS in both male and female participants. In the male participants, the correlation coefficient increased progressively from the normal group to the osteoporosis group. In the female group, we observed a significant positive correlation between height and TBS, and in the male group a significant negative correlation between weight and TBS was observed.

CONCLUSIONS

BMI and weight are closely correlated to body fat content. BMD was positively correlated to BMI and weight, while TBS was negatively correlated to BMI and weight. Therefore, although BMI causes an increase in BMD, it appears to be negatively affecting bone quality.

Long-term hypovitaminosis D and secondary hyperparathyroidism outcomes of the Roux-en-Y gastric bypass: a systematic review

INTRODUCTION

Pre-operative Vitamin D deficiency is markedly prevalent in prospective bariatric surgery patients. While bariatric surgery leads to significant weight loss, it can exacerbate or prolong Vitamin D deficiency. We systematically reviewed the literature to assess whether secondary hyperparathyroidism is maintained in the medium to long term in patients following the Roux-en-Y gastric bypass.

METHODS

A comprehensive literature search was conducted through Medline, Embase, Scopus, Web of Science, Dare, Cochrane library and HTA database. The search terms used were bariatric surgery, gastric bypass and hyperparathyroidism.

RESULTS

Fourteen studies were included (n = 2688 subjects). Parathyroid hormone levels rose gradually from a mean pre-operative level of 5.69 ± 1.2 pmol/L to 6.36 ± 0.77 pmol/L, 7.59 ± 0.73 pmol/L and 8.29 ± 1.41 pmol/L at 2 years, between 2 and 5 years, and beyond 5 years, respectively. Vitamin D levels slowly fell to a mean of 20.50 ± 4.37 ng/mL and 20.76 ± 3.80 ng/mL between follow-up intervals 2-5 years and beyond 5, respectively.

CONCLUSION

It appears that hyperparathyroidism persists at 5-year follow-up after gastric bypass, despite most patients being supplemented with calcium and Vitamin D.

Trabecular Bone Score: A New DXA-Derived Measurement for Fracture Risk Assessment

Trabecular bone score (TBS) is a novel method that assesses skeletal texture from spine dual-energy X-ray absorptiometry (DXA) images. TBS improves fracture-risk prediction beyond that provided by DXA bone mineral density (BMD) and clinical risk factors, and can be incorporated to the Word Health Organization Fracture Risk Assessment tool (FRAX®) to enhance fracture prediction. There is insufficient evidence that TBS can be used to monitor treatment with bisphosphonates. TBS may be particularly helpful to assess fracture risk in diabetes. This article reviews technical and clinical aspects of TBS and its potential utility as a clinical tool to predict fracture risk.