Divergent effects of obesity on bone health

Characterisation of the influence of dietary fat and sugar on bone health utilising densitometry, micro-computed tomography and histomorphometry

Obesogenic feeding can affect systemic metabolism and impact bone health and microarchitecture, but the findings of published studies often appear contradictory. This study aimed to compare the effects of a medium-fat/high-sugar (MF/HS) and a high-fat/high-fructose (HF/Fr) diet on the femora of weanling male Wistar rats, examining bone mineral content and density (BMC, BMD), cortical and cancellous bone microarchitecture and the cell populations within bone. Furthermore, we explored the correlations between circulating bone-targeting factors (in particular leptin, adiponectin and insulin) and bone parameters. Rats were assigned to one of three dietary groups (control: CON; MF/HS: OB1; HF/Fr: OB2; n = 12 each) for 17 weeks. Right-hand side femora were subjected to densitometry to measure BMC and BMD, and micro-computed tomography (μCT) was utilised to assess cortical and cancellous bone. Osteoblast (N.Ob), osteoclast (N.Oc), adipocyte (N.Ad) and chondrocyte numbers (N.Ch) were quantified histomorphometrically. Diet OB1 was largely beneficial to bone, while diet OB2 exerted detrimental effects on BMC, BMD, bone microarchitecture and bone cell populations. In cortical bone, N.Ob was positively correlated with BMD, cortical area and serum leptin. In cancellous bone, N.Ob was positively correlated with serum leptin and BMD, while N.Oc was negatively correlated with serum leptin. Overall, these findings support a role for endogenous circulating leptin in promoting bone formation. We conclude that the impact of different obesogenic diets may be driven by individual dietary effects on circulating factors, which may partly explain the contradictory reports in existing literature on the impact of HF and HS diets on bone.

Sugar-Sweetened Beverage Consumption and Height Loss in Adults: A Longitudinal Analysis in the EPIC-Norfolk Study

BACKGROUND

Height loss in aging has been recognized to reflect a decline in musculoskeletal health but not investigated in relation to dietary factors, such as sugar-sweetened beverages (SSBs), the consumption of which may deteriorate musculoskeletal health.

OBJECTIVES

This study aimed to evaluate the longitudinal association of habitual consumption of total SSBs and its subtypes with height loss and examine effect-modification by age, sex, and anthropometry.

METHODS

We evaluated 16,230 adults aged 40-79 y in the European Prospective Investigation into Cancer and Nutrition-Norfolk cohort. At baseline (1993-1997), SSB consumption (soft drinks, squashes, sweetened milk beverages, sweetened coffee/tea, and sweetened alcoholic beverages) was assessed using 7-d food diaries. Height was objectively measured at the baseline, second (1997-2000), and third (2004-2011) health checks. Multivariable linear regression was used to examine baseline SSB consumption and the rate of height change over the follow-up.

RESULTS

The median (IQR) height change was -1.07 (-2.09 to -0.28) cm/10 y. Adjusted for potential confounders including behavioral factors, medications, and baseline body mass index (BMI), total SSB consumption was associated with height loss (β: -0.024; 95% CI: -0.046, -0.001 cm/10 y per 250 g/d of SSB), and similar results were seen for the individual beverages, except for sweetened milk beverages (β: +0.07; 95% CI: -0.16, 0.30), with wide CIs. No effect-modification by prespecified factors was evident, except for baseline BMI (P-interaction = 0.037). Total SSB consumption was associated with height loss (-0.038; 95% CI: -0.073, -0.004) in participants with BMI ≤ 25 kg/m2 but not apparently in those with BMI > 25 kg/m2.

CONCLUSIONS

SSB consumption was modestly associated with height loss, particularly in adults with normal weight status.

Insufficient Bone Mineralization to Sustain Mechanical Load of Weight in Obese Boys: A Cross-Sectional Study

CONTEXT

The increase in bone mineral content (BMC) and density (BMD) measured by dual-energy x-ray absorptiometry (DXA) in obese children may not sustain the mechanical load associated with weight, and the factors influencing bone mineralization are not well known.

OBJECTIVE

We described bone mineralization in boys with overweight/obesity and leanness in relation to body composition.

METHODS

Cross-sectional study in the Pediatric Endocrinology Unit of Angers University Hospital with 249 overweight/obese boys aged 8-18 who underwent DXA and insulin, testosterone, and IGF-1 measurements. Bone mineralization was compared with data from 301 lean boys of similar age and height from NHANES 2011-2015, using the same DXA model. Path analyses were performed to evaluate factors associated with total body less head (TBLH) BMC.

RESULTS

The mean age- and height-adjusted difference in TBLH BMC between obese and lean boys was 241 ± 20 g/cm2. Each 1 kg/m2 increase in BMI was associated with +39 ± 6 g of TBLH BMC in lean subjects vs + 25 ± 3 g in obese subjects (P < .05). Each 1 kg/m2 increase in lean BMI (LBMI) was associated with +78 ± 5 g of TBLH BMC in lean and obese boys, and each 1 kg/m2 increase in fat mass index (FMI) was associated with a decrease of 9 ± 3 g of TBLH BMC. The TBLH BMC was directly positively influenced by LBMI and indirectly and positively influenced by IGF-1, testosterone, and insulin (mediated through height and LBMI). FMI indirectly influenced TBLH BMC, both positively through LBMI and negatively through its negative impact on IGF-1 and testosterone.

CONCLUSION

The increase in bone mineralization in obese children does not adapt to the increase in body mass.

Association between Metabolic Obesity Phenotypes and the Burden of Hospitalized Postmenopausal Patients Concomitant with Osteoporosis: A Retrospective Cohort Study Based on the National Readmission Database

BACKGROUND

The present definition of obesity based on body mass index (BMI) is not accurate and effective enough to identify hospitalized patients with a heavier burden, especially for postmenopausal hospitalized patients concomitant with osteoporosis. The link between common concomitant disorders of major chronic diseases such as osteoporosis, obesity, and metabolic syndrome (MS) remains unclear. Here, we aim to evaluate the impact of different metabolic obesity phenotypes on the burden of postmenopausal hospitalized patients concomitant with osteoporosis in view of unplanned readmissions.

METHODS

Data was acquired from the National Readmission Database 2018. The study population was classified into metabolically healthy non-obese (MHNO), metabolically unhealthy non-obese (MUNO), metabolically healthy obese (MHO), and metabolically unhealthy obese (MUO) patients. We estimated the associations between metabolic obesity phenotypes and 30- and 90-day unplanned readmissions. A multivariate Cox Proportional Hazards (PH) model was used to assess the effect of factors on endpoints, with results expressed as HR and 95% CI.

RESULTS

The 30-day and 90-day readmission rates for the MUNO and MUO phenotypes were higher than that of the MHNO group (all p < 0.05), whereas no significant difference was found between the MHNO and MHO groups. For 30-day readmissions, MUNO raised the risk mildly (hazard ratio [HR] = 1.110, p < 0.001), MHO had a higher risk (HR = 1.145, p = 0.002), and MUO further elevated this risk (HR = 1.238, p < 0.001). As for 90-day readmissions, both MUNO and MHO raised the risk slightly (HR = 1.134, p < 0.001; HR = 1.093, p = 0.014, respectively), and MUO had the highest risk (HR = 1.263, p < 0.001).

CONCLUSIONS

Metabolic abnormalities were associated with elevated rates and risks of 30- or 90-day readmission among postmenopausal hospitalized women complicated with osteoporosis, whereas obesity did not seem to be innocent, and the combination of these factors led to an additional burden on healthcare systems and individuals. These findings indicate that clinicians and researchers should focus not only on weight management but also metabolism intervention among patients with postmenopausal osteoporosis.

Relation between adipose tissue and the musculoskeletal unit in a group of postmenopausal women

Introduction

Involutional changes observed during aging increase rapidly in the postmenopausal period. These changes include body composition by affecting bone, muscle and fat tissue. A number of studies have investigated the mutual interaction between bone and muscle tissue, whereas adipose tissue had not been studied thoroughly.The aim of the present study was to assess the relation between fat tissue parameters and the musculoskeletal unit.

Material and methods

The study was conducted in a group of 120 postmenopausal women with an average age of 69 years (59-81; SD 5.3). All women had been asked to complete a questionnaire (medical history) and underwent a total body composition analysis [bone mineral density (BMD)] testing (spine and/or neck) followed by a handgrip test.

Results

The study revealed strong correlations between appendicular skeletal muscle mass index - appen.lean/height², visceral adipose tissue area (VAT) and fat/mass/height² index (r = 0.589 and 0.658 respectively; p < 0.001). The results were not supported by muscle strength (handgrip). The authors identified correlations between the bone parameters and adipose tissue but these were identified as weak or moderate (p < 0.05). Special emphasis should be placed on the relation between the trabecular bone score (TBS) and VAT area (r = -0.385, p < 0.001).

Conclusions

There is a strong dependence between muscle and adipose tissues. Despite the fact that the increase in fat is correlated with the growth of muscle tissue, it is not accompanied by better quality of the muscle (handgrip). Bone microarchitecture is more related to VAT area than neck/spine BMD.

Influence of Obesity on Bone Turnover Markers and Fracture Risk in Postmenopausal Women

Background and aims: The relationship between obesity and bone metabolism is controversial. In recent decades, the protective role of obesity in the development of osteoporosis is questioned. The aims of this study are the following: to evaluate the differences in bone turnover markers between postmenopausal women with and without obesity and to compare the risk of fracture at five years between these groups. Methods: An observational longitudinal prospective cohort study of postmenopausal women with obesity (O) (body mass index (BMI) > 30 kg/m2) and non-obesity (NoO) (BMI < 30 kg/m2) is designed. 250 postmenopausal women are included in the study (NoO: 124 (49.6%) and O: 126 (50.4%)). It measures epidemiological variables, dietary variables (calcium intake, vitamin D intake, smoking, alcohol consumption, and physical activity), biochemicals (β-crosslap, type I procollagen amino-terminal peptide (P1NP), 25OH-vitamin D, and parathyroid hormone (PTH)), anthropometric variables, and fracture data five years after the start of the study. The mean age is 56.17 (3.91) years. Women with obesity showed lower levels of vitamin D (O: 17.27 (7.85) ng/mL, NoO: 24.51 (9.60) ng/mL; p < 0.01), and higher levels of PTH (O: 53.24 (38.44−65.96) pg/mL, NoO: 35.24 (25.36−42.40) pg/mL; p < 0.01). Regarding the bone formation marker (P1NP), it was found to be high in women without obesity, O: 45.46 (34.39−55.16) ng/mL, NoO: 56.74 (45.34−70.74) ng/mL; p < 0.01; the bone resorption marker (β-crosslap) was found to be high in women with obesity, being significant in those older than 59 years (O: 0.39 (0.14) ng/mL, NoO 0.24 (0.09) ng/mL; p < 0.05). No differences are observed in the risk of fracture at 5 years based on BMI (OR = 0.90 (95%CI 0.30−2.72); p = 0.85). Conclusions: Postmenopausal women with obesity showed lower levels of bone formation markers; older women with obesity showed higher markers of bone resorption.

Bone microarchitecture, bone mineral density and bone turnover in association with glycemia and insulin action in women with prior gestational diabetes

OBJECTIVE

The aim of this cross-sectional study was to comprehensively assess bone health in women with prior gestational diabetes mellitus, including bone microarchitecture (TBS), bone mineral density (BMD, DXA) and bone turnover (osteocalcin).

DESIGN, PATIENTS AND MEASUREMENTS

Study participants underwent a detailed anthropometric, biochemical and hormone assessment, including insulin and osteocalcin measurement. BMD was measured at lumbar spine, femur neck and total hip using DXA and TBS derived from lumbar spine DXA images using TBS iNsight software.

RESULTS

A total of 240 women (mean age: 33.3 ± 5.0 years; median postpartum duration: 34 [interquartile range 13.0-54.5] months were evaluated. At the current visit, 115 (47.9%) and 36 (15%) women had prediabetes and diabetes, respectively. Women with dysglycemia (diabetes/prediabetes) had a higher BMD at all three sites, compared to those with normoglycemia; however, the difference was not statistically significant. Women with dysglycemia had a significantly lower TBS (1.32 ± 0.09 vs. 1.35 ± 0.09; p = .038). In the fully adjusted model, the odds ratio for association between diabetes and low TBS was 2.92 (95% confidence interval: 1.20, 7.08; p = .018). Women with dysglycemia had significantly lower serum osteocalcin levels (18.6 ± 8.5 ng/ml vs. 21.5 ± 9.7 ng/ml; p = .018). HOMA-IR (r = -.285, p < .001) was negatively correlated, while Matsuda index (r = .274, p < .001) and disposition index (r = .159, p = .016) were positively correlated with serum osteocalcin levels.

CONCLUSIONS

Bone health is affected early in the natural history of diabetes and is associated with an overall low bone turnover state.

Does the severity of obesity influence bone density, geometry and strength in adolescents?

BACKGROUND

Relationships between the severity of obesity and bone health remain underexplored.

OBJECTIVES

To compare whole-body and localized bone mineral content (BMC) and density (BMD), trabecular bone score (TBS) and hip geometry and strength between adolescents with obesity versus extreme obesity.

METHODS

This cross-sectional study included 154 adolescents (12-15 years, 62% females) who were classified as having obesity (OG, [95th-99th] percentile) or extreme obesity (EOG, >99th percentile). Fat mass (FM), lean mass (LM), BMC, BMD for total-body-less-head (TBLH), lumbar spine (LS), hip, TBS and geometric and strength indices at the narrow-neck (NN), femoral shaft (FS) and intertrochanteric regions (IT) were assessed by Dual-X-ray Absorptiometry (DXA).

RESULTS

There was no significant sex-interaction. For both sexes, TBLH BMC and BMD were not different between groups. TBS was lower in EOG compared with OG in both sexes in univariate analysis and after adjustment with maturation and body weight (p < 0.05). Hip BMD was significantly higher in the EOG compared to OG only after adjustment with maturation and fat mass percentage (p < 0.05 for men, p < 0.01 for women). For both sexes, TBLH, LS and hip BMC and BMD positively correlated with weight, BMI, LM and FM. TBS negatively correlated with BMI-percentile in both sexes, with a negative correlation with FM for males alone. Hip BMC and BMD, BMD, ACT and CSA at the three hip sites positively correlated with BMI-percentile in males.

CONCLUSIONS

Extreme obesity impacts bone health depending on anatomical sites, altering lumbar trabecular bone in both males and females adolescents.

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.

Type 2 diabetes and bone fragility- An under-recognized association

BACKGROUND AND AIMS

Diabetes and osteoporosis are common chronic disorders with growing prevalence in the aging population. Skeletal fragility secondary to diabetes increases the risk of fractures and is underestimated by currently available diagnostic tools like fracture risk assessment (FRAX) and dual-energy X-ray absorptiometry (DXA). In this narrative review we describe the relationship and pathophysiology of skeletal fragility and fractures in Type 2 diabetes (T2DM), effect of glucose lowering medications on bone metabolism and the approach to diagnosing and managing osteoporosis and bone fragility in people with diabetes (PWD).

METHODS

A literature search was conducted on PubMed for articles in English that focused on T2DM and osteoporosis or bone/skeletal fragility. Articles considered to be of direct clinical relevance to physicians practicing diabetes were included.

RESULTS

T2DM is associated with skeletal fragility secondary to compromised bone remodeling and bone turnover. Long duration, poor glycemic control, presence of chronic complications, impaired muscle function, and anti-diabetic medications like thiazolidinediones (TZD) are risk factors for fractures among PWD. Conventional diagnostic tools like DXA and FRAX tool underestimate fracture risk in diabetes. Presence of diabetes does not alter response to anti-osteoporotic treatment in post-menopausal women.

CONCLUSION

Estimation of fragility fracture risk should be included in standard of care for T2DM along with screening for traditional complications. Physicians should proactively screen for and manage osteoporosis in people with diabetes. It is important to consider effects on bone health when selecting glucose lowering agents in people at risk for fragility fractures.

Obesity, vitamin D status and physical activity: 1,25(OH)2D as a potential marker of vitamin D deficiency in obese subjects

BACKGROUND

Obesity has been regarded to be protective against fracture in spite of its association with low levels of vitamin D. Vitamin D is the key regulator of bone metabolism and its deficiency contributes to higher level of parathyroid hormone (PTH), leading to the activation of bone turnover.

METHODS

We studied 161 subjects of which 65 were young healthy subjects and 96 were elderly subjects. We measured creatinine, 25(OH)D, 1,25(OH)2D, PTH, albumin, and calcium plasma levels, we evaluated physical activity, and we calculated BMI. A sub-cohort of elderly subjects also underwent DXA scans.

RESULTS

Overweight and obese subjects, as well as underweight ones, had lower levels of vitamin D but normal serum concentrations of 1,25(OH)2D and PTH was higher in underweight and obese subjects. Moreover, we found a nonlinear relationship between body mass index (BMI) and PTH with a significant U-shaped exponential regression. Regardless of BMI, 25(OH)D mean levels were higher in subjects who practice physical activity.

CONCLUSIONS

These findings suggest that physical activity and BMI had a significant effect on the metabolism of bone and vitamin D, but the effect of BMI was different in underweight, normal weight or obese subjects. In obesity the real vitamin D deficiency could be estimate by serum 1,25(OH)2D concentrations whose lower levels contribute to the higher PTH production and consequently to bone loss and to a greater fracture risk.

Lean body mass, body fat percentage, and handgrip strength as predictors of bone mineral density in postmenopausal women

Objective:

This study was conducted to assess lean body mass, body fat percentage, and handgrip strength in the prediction of bone mineral density (BMD) in postmenopausal women.

Materials and Methods:

This cross-sectional study included 102 postmenopausal women aged between 45 and 80 years (mean age 58) who were screened for osteoporosis using a dual-energy X-ray absorptiometry scan at the lumbar spine. The lean body mass, body fat percentage, and handgrip strength were calculated.

Results:

The lean body mass, body fat percentage, and handgrip strength were having a positive association (correlation coefficient: 0.48, 0.29, and 0.3, respectively) with BMD.

Conclusion:

Lean body mass, body fat percentage, and handgrip strength can detect early loss of BMD in postmenopausal women leading to early screening for osteoporosis resulting in early interventions minimizing BMD loss over a much longer period after menopause.

Bone Mineral Density in Severely Obese Women: Health Risk and Health Protective Risk Factors in Three Different Bone Sites

Factors associated with bone mineral density (BMD) are poorly known in severely obese individuals i.e., a body mass index (BMI) > 35 kg/m2. The objectives of this study were to describe the bone health profile of severely obese Brazilian women, to identify the health risk and health protective factors for BMD in this group and to assess whether these factors vary according to three different bone sites. BMD was assessed using dual-energy X-ray absorptiometry (DXA). This study analyzed baseline data from 104 women who had an average BMI of 43.7 ± 4.5 kg/m2 and presented the following BMD status: 1.283 ± 0.094 g/cm2 for total body, 1.062 ± 0.159 g/cm2 for vertebral column and 1.195 ± 0.134 g/cm2 for hip. They took part in the "Effect of nutritional intervention and olive oil in severe obesity" randomized clinical trial (DieTBra Trial). The risk factors negatively associated with lower BMD were age ≥50 years for the three bone sites i.e., total body, vertebral column and hip. Smoking for total body BMD (p = 0.045); BMI ≥ 50kg/m2 for vertebral column and hip; menopause for hip; high C-reactive protein (CRP) levels (p = 0.049), insufficient zinc (p = 0.010) and previous fracture for vertebral column (p = 0.007). The protective factors positively associated with BMD were physical activity (≥150 min/week (p = 0.001)) for hip; type 2 diabetes mellitus (DM2) (p < 0.0001) total body and adequate vitamin D levels from food consumption (p = 0.039) for vertebral column. A BMI ≥ 50 kg/m2 was a risk factor for lower BMD. The findings showed that protective and risk factors varied by bone site. The original study is registered with ClinicalTrials.gov. (protocol number: NCT02463435).

Association between changes in bioactive osteocalcin and glucose homeostasis after biliopancreatic diversion

PURPOSE

Bone may regulate glucose homeostasis via uncarboxylated bioactive osteocalcin (ucOCN). This study explored whether changes in ucOCN and bone remodeling are associated with change in glucose homeostasis after biliopancreatic diversion (BPD).

METHODS

In this secondary exploratory analysis of a 1-year prospective observational study, 16 participants (11 men/5 women; 69% with type 2 diabetes; mean BMI 49.4 kg/m²) were assessed before, 3 days, 3 months and 12 months after BPD. Changes in plasma ucOCN and bone markers (C-terminal telopeptide (CTX), total osteocalcin (OCN)) were correlated with changes in insulin resistance or sensitivity indices (HOMA-IR; adipose tissue insulin resistance index (ADIPO-IR) and insulin sensitivity index (SI) from the hyperinsulinemic-euglycemic clamp), insulin secretion rate (ISR) from the hyperglycemic clamp, and disposition index (DI: SI × ISR) using Spearman correlations before and after adjustment for weight loss.

RESULTS

ucOCN was unchanged at 3 days but increased dramatically at 3 months (+257%) and 12 months (+498%). Change in ucOCN correlated significantly with change in CTX at 3 months (r = 0.62, p = 0.015) and 12 months (r = 0.64, p = 0.025) before adjustment for weight loss. It also correlated significantly with change in fasting insulin (r = -0.53, p = 0.035), HOMA-IR (r = -0.54, p = 0.033) and SI (r = 0.52, p = 0.041) at 3 days, and ADIPO-IR (r = -0.69, p = 0.003) and HbA_1c (r = -0.69, p = 0.005) at 3 months. Change in OCN did not correlate with any glucose homeostasis indices. Results were similar after adjustment for weight loss.

CONCLUSION

The increase in ucOCN may be associated with the improvement in insulin resistance after BPD, independently of weight loss. These findings need to be confirmed in larger, less heterogeneous populations.

Vitamin D Status in Children With Forearm Fractures: Incidence and Risk Factors

Introduction:

The association between vitamin D status and fracture characteristics in children remains ambiguous. We hypothesized that vitamin D deficient or insufficient children would have an increased risk of forearm fractures severe enough to require surgical management.

Methods:

One hundred children with low-energy forearm fractures were prospectively enrolled from a single hospital. Each participant answered a questionnaire focusing on the risk factors for vitamin D deficiency. Fractures were categorized as requiring nonsurgical or surgical management. Vitamin D status was based on the measurement of 25-hydroxyvitamin D (25(OH)D) concentration obtained during the clinic visit and compared between the two fracture groups.

Results:

The cohort exhibited a mean age of 9.8 ± 3.2 years (range: 3-15 years), comprising 65 (65%) men and 35 (35%) women. Overall, mean 25(OH)D was 27.5 ± 8.3 ng/mL. Using the Endocrine Society guidelines, 21% of patients were categorized as “vitamin D deficient” (25(OH)D ≤ 20 ng/mL) and 49% as “vitamin D insufficient” (25(OH)D: 21 to 29 ng/mL). Stratification by intervention revealed a mean 25(OH)D of 23.3 ± 8.8 ng/mL in the surgical group (n = 12) and 28.1 ± 8.1 in the nonsurgical group (n = 88) (P = 0.057). Fifty percent of the surgical group were “vitamin D deficient” compared with 17% of the nonsurgical group (P = 0.017). The relative risk of requiring surgical treatment in children with forearm fracture and vitamin D deficiency (25(OH)D < 20 ng/mL) was 3.8. 25(OH)D level, negatively correlated with body mass index (r = −0.21, P = 0.044); 9 surgical patients were overweight or obese (as defined by the criteria of the Centers for Disease Control and Prevention). 25(OH)D level was significantly lower in non-Caucasians compared with Caucasians (26.0 ± 7.2 versus 32.5 ± 9.9 ng/mL; P = 0.0008).

Discussion:

Vitamin D deficiency is common in children with forearm fractures and may be a contributing risk factor for forearm fractures requiring surgical management in children.

Conclusion:

Vitamin D deficiency and inefficiency are common in children with low energy forearm fractures, especially in obese children and in fractures requiring surgical treatment.

Factors associated with bone mineral density in adults: a cross-sectional population-based study

OBJECTIVE

This study aimed to analyze the association between lumbar spine, femoral neck, total hip bone mineral density (biophysical bone health assessment parameter), and sociodemographic, anthropometric, behavioral, and health condition factors in Brazilian adults.

METHOD

This is a cross-sectional, population-based study performed with individuals of both genders, aged between 20 and 59 (n=701). The dependent variables were evaluated by Dual Energy X-ray Absorptiometry. The independent variables were evaluated through a questionnaire, anthropometric evaluation and blood collection. The association between bone mineral density and the independent variables was evaluated by linear regression analysis. All analyses were stratified by gender.

RESULTS

Men presented higher bone mineral density than women. Bone mineral density was inversely associated with age range and directly associated with nutritional status in both genders and in the three bone sites analyzed. In addition, 25 Hydroxyvitamin D deficient status among men and contraceptive use among women were associated with lower bone mineral density, and a significant association was only found with lumbar spine bone mineral density in women.

CONCLUSION

The factors associated with bone health among men were age, skin color, nutritional status, and vitamin D status. For women, the associated factors with bone health were age, skin color, nutritional status and contraceptive use.

Genetic variants affecting bone mineral density and bone mineral content at multiple skeletal sites in Hispanic children

CONTEXT

Osteoporosis is a major public health burden with significant economic costs. However, the correlates of bone health in Hispanic children are understudied.

OBJECTIVE

We aimed to identify genetic variants associated with bone mineral density (BMD) and bone mineral content (BMC) at multiple skeletal sites in Hispanic children.

METHODS

We conducted a cross-sectional genome-wide linkage analysis, genome-wide and exome-wide association analysis of BMD and BMC. The Viva La Familia Study is a family-based cohort with a total of 1030 Hispanic children (4-19 years old at baseline) conducted in Houston, TX. BMD and BMC were measured by Dual-energy X-ray absorptiometry.

RESULTS

Significant heritability were observed for BMC and BMD at multiple skeletal sites ranging between 44 and 68% (P < 2.8 × 10-9). Significant evidence for linkage was found for BMD of pelvis and left leg on chromosome 7p14, lumbar spine on 20q13 and left rib on 6p21, and BMC of pelvis on chromosome 20q12 and total body on 14q22-23 (logarithm of odds score > 3). We found genome-wide significant association between BMC of right arm and rs762920 at PVALB (P = 4.6 × 10-8), and between pelvis BMD and rs7000615 at PTK2B (P = 7.4 × 10-8). Exome-wide association analysis revealed novel association of variants at MEGF10 and ABRAXAS2 with left arm and lumber spine BMC, respectively (P < 9 × 10-7).

CONCLUSIONS

We identified novel loci associated with BMC and BMD in Hispanic children, with strongest evidence for PTK2B. These findings provide better understanding of bone genetics and shed light on biological mechanisms underlying BMD and BMC variation.

Trabecular bone score and bone turnover markers in men with DISH: Data from the Camargo Cohort study

OBJECTIVE

Diffuse idiopathic skeletal hyperostosis (DISH) has been associated with an increased risk of vertebral fracture. To date, no studies have investigated the relationship between DISH and bone microstructure assessed by the trabecular bone score (TBS).

METHODS

Cross-sectional study, nested in a prospective population-based cohort. All men (968) aged≥50 years were included. Clinical covariates, DISH, TBS, serum bone turnover markers and bone mineral density (BMD) were analyzed.

RESULTS

Mean age of participants was 65 ± 9 years. 207 (21.6%) had DISH. DISH subjects were older, had higher body mass index (BMI) and abdominal perimeter, lower glomerular filtration rate (GFR), and higher prevalence of metabolic syndrome (MetS) than non-DISH (NDISH) subjects. Bone mineral density at the lumbar spine (LS-BMD) was significantly higher in the DISH group. TBS values were 1.317 [1.303-1.331] for DISH and 1.334 [1.327-1.341] for NDISH subjects, after adjusting by age, BMI, abdominal perimeter, arterial hypertension, diabetes mellitus, MetS, GFR, serum alkaline phosphatase (ALP), LS and femoral neck BMD (p = 0.03). Serum ALP levels were higher in DISH subjects, showing an inverse correlation with TBS that remained significant after adjusting by age and BMI.

CONCLUSIONS

TBS values were significantly lower in men with DISH irrespective of age, BMI and BMD, suggesting that the presence of DISH might be related to a worse trabecular microstructure.

Resistance Training for Older Adults: Position Statement From the National Strength and Conditioning Association

Fragala, MS, Cadore, EL, Dorgo, S, Izquierdo, M, Kraemer, WJ, Peterson, MD, and Ryan, ED. Resistance training for older adults: position statement from the national strength and conditioning association. J Strength Cond Res 33(8): 2019-2052, 2019-Aging, even in the absence of chronic disease, is associated with a variety of biological changes that can contribute to decreases in skeletal muscle mass, strength, and function. Such losses decrease physiologic resilience and increase vulnerability to catastrophic events. As such, strategies for both prevention and treatment are necessary for the health and well-being of older adults. The purpose of this Position Statement is to provide an overview of the current and relevant literature and provide evidence-based recommendations for resistance training for older adults. As presented in this Position Statement, current research has demonstrated that countering muscle disuse through resistance training is a powerful intervention to combat the loss of muscle strength and muscle mass, physiological vulnerability, and their debilitating consequences on physical functioning, mobility, independence, chronic disease management, psychological well-being, quality of life, and healthy life expectancy. This Position Statement provides evidence to support recommendations for successful resistance training in older adults related to 4 parts: (a) program design variables, (b) physiological adaptations, (c) functional benefits, and (d) considerations for frailty, sarcopenia, and other chronic conditions. The goal of this Position Statement is to a) help foster a more unified and holistic approach to resistance training for older adults, b) promote the health and functional benefits of resistance training for older adults, and c) prevent or minimize fears and other barriers to implementation of resistance training programs for older adults.

Factors associated with bone mineral content in adults: a population-based study

OBJECTIVE

To determine the association among bone mineral content, sociodemographic, anthropometric and behavioral factors, and health status of Brazilian adults.

METHODS

This was a cross-sectional, population-based study including 701 individuals from both sexes aged between 20 and 59 years. DEXA was used to evaluate dependent variable. The associations were evaluated using linear regression models stratified by sex.

RESULTS

When mean bone mineral content values were compared, we found significant differences related to sex and all the independent variables evaluated. In the adjusted models, we identified an inverse association between bone mineral content and age in both sexes. Among men, to be overweight and/or obese, be highly educated, and have almost sufficiency of 25(OH)D were associated with higher bone mineral content values. On the other hand, among women, to be non-white skin color, overweight and/or obese were associated with better bone health. The main factors associated with low total bone mineral density were advanced age, white skin color, low level of formal education, eutrophy, and 25(OH)D deficiency.

CONCLUSION

Our results may help to identify adults who are at higher risk, and these findings should be used as guidelines for prevention and early diagnosis.

Associations between the lipid profile and the lumbar spine bone mineral density and trabecular bone score in elderly Iranian individuals participating in the Bushehr Elderly Health Program: a population-based study

We hypothesized that the lipid profile or dyslipidemia may have an influence on the bone mineral density and bone microstructure in an elderly Iranian population. The results of this study showed some significant associations between the serum lipid levels and the lumbar spine and femoral areal bone mineral densities and the trabecular bone score (TBS).

PURPOSE

Serum lipid abnormalities are possible risk factors for cardiovascular diseases and osteoporosis. Our aim was to evaluate the associations between the lipid profile and the areal bone mineral density (aBMD) and trabecular bone score in an elderly Iranian population.

METHODS

The study subjects included 2426 elderly women and men participating in the second stage of the Bushehr Elderly Health program, a population-based prospective cohort study. The aBMDs of the lumbar spine and femoral neck and the lumbar spine texture were measured using dual-energy X-ray absorptiometry and the TBS algorithm, respectively. The associations between the lipid profiles and the aBMDs and TBSs were examined using multivariable linear regression analyses stratified by sex and adjusted for potential confounders.

RESULTS

In men, we found negative correlations between the lumbar spine aBMD and TBS and the total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels (TC: p < 0.001 and p < 0.006, HDL-C: p = 0.002 and p = 0.004, and LDL-C: p < 0.001 and p < 0.009, respectively). However, only the HDL-C level was negatively associated with the aBMD in women (p = 0.016). A positive and statistically significant correlation was found between the serum triglyceride (TG) level and the aBMD in the women (p < 0.001). The TG level and the TBS were not statistically significantly correlated in either sex, and the TBS was not correlated with any of the lipid values in women.

CONCLUSION

The results of this study showed some significant but generally weak associations between the lipid profile and the aBMD. The associations that were significant for both the men and the women included positive associations between the TG level and the femoral neck aBMD, as well as the HDL-C level and the femoral neck and lumbar spine aBMDs.

Lean Body Mass in the Prediction of Bone Mineral Density in Postmenopausal Women

Owing to conflicting results of the association between body composition and bone mineral density (BMD), we investigated the relationship between fat mass (FM), lean mass (LM), and BMD in New Zealand postmenopausal women. We hypothesized that increased LM will indicate a higher BMD. A cross-sectional study was performed examining the associations between body composition, anthropometric measures, activity energy expenditure, and bone health status (using dual-energy X-ray absorptiometry [DXA]). A total of 127 healthy postmenopausal women aged between 54 and 81 years. Both FM and LM were significantly associated with BMD at all sites. However, LM, not FM, was the strongest predictor of femoral neck (FN) BMD (β = 0.497, p < 0.001), hip BMD (β = 0.495, p < 0.001), spine BMD (β = 0.449, p < 0.001), and whole body BMD (β = 0.406, p < 0.001). Age was negatively associated with FN and hip BMD. LM was positively associated with FN, spine, hip, and whole body BMD. Our findings suggest the need to increase LM rather than FM highlighting the importance of physical activity for this age group.

Glycemic Control and Bone Turnover in Older Mexican Americans with Type 2 Diabetes

Altered bone quality, caused by underlying metabolic changes of type 2 diabetes (T2D), has been hypothesized to cause altered bone strength and turnover leading to increased fracture risk in T2D patients. Current understanding about changes in bone turnover markers in T2D patients is mainly based on studies focused on Caucasian men and women. However, Hispanic populations have the highest prevalence of both T2D and osteoporosis in the US. We investigated associations of glycemic control (in terms of glycated hemoglobin [HbA1c]) and bone turnover rate in 69 older (≥50 years) Mexican American Cameron County Hispanic Cohort (CCHC) participants with T2D. Multivariable analyses were conducted to assess the associations between HbA1c (%), serum osteocalcin (OC), and serum sclerostin. In agreement with published reports from other racial/ethnic populations, our study found that lower bone turnover (indicated by lower serum OC) occurred in Mexican American men with T2D who had poorer glycemic control. For the women in our study, we found no significant association between glycemic control and OC. In contrast, HbA1c was positively associated with sclerostin for women, with near significance (p = 0.07), while no association was found in men. We recommend screening Mexican American individuals with T2D, specifically those with poor glycemic control, for bone loss and fracture risk.

Endocrine-disrupting chemicals, epigenetics, and skeletal system dysfunction: exploration of links using bisphenol A as a model system

Early life exposures to endocrine-disrupting chemicals (EDCs) have been associated with physiological changes of endocrine-sensitive tissues throughout postnatal life. Although hormones play a critical role in skeletal growth and maintenance, the effects of prenatal EDC exposure on adult bone health are not well understood. Moreover, studies assessing skeletal changes across multiple generations are limited. In this article, we present previously unpublished data demonstrating dose-, sex-, and generation-specific changes in bone morphology and function in adult mice developmentally exposed to the model estrogenic EDC bisphenol A (BPA) at doses of 10 μg (lower dose) or 10 mg per kg bw/d (upper dose) throughout gestation and lactation. We show that F1 generation adult males, but not females, developmentally exposed to bisphenol A exhibit dose-dependent reductions in outer bone size resulting in compromised bone stiffness and strength. These structural alterations and weaker bone phenotypes in the F1 generation did not persist in the F2 generation. Instead, F2 generation males exhibited greater bone strength. The underlying mechanisms driving the EDC-induced physiological changes remain to be determined. We discuss potential molecular changes that could contribute to the EDC-induced skeletal effects, with an emphasis on epigenetic dysregulation. Furthermore, we assess the necessity of intact sex steroid receptors to mediate these effects. Expanding future assessments of EDC-induced effects to the skeleton may provide much needed insight into one of the many health effects of these chemicals and aid in regulatory decision making regarding exposure of vulnerable populations to these chemicals.

The Association of Fat and Lean Tissue With Whole Body and Spine Bone Mineral Density Is Modified by HIV Status and Sex in Children and Youth

BACKGROUND

HIV-infected (HIV-pos) male children/youth showed lower bone mineral density at sexual maturity than HIV-uninfected (HIV-neg) females. It is not known whether complications of HIV disease, including abnormal body fat distribution, contribute to lower bone accrual in male HIV-pos adolescents.

METHODS

In a cross-sectional study, we evaluated the relationship between body composition (fat and lean mass) and bone mass in HIV-pos and HIV-neg children/youth and determined if it is modified by HIV status and sex. We used generalized estimating equations to simultaneously model the effect of fat/lean mass on multiple bone outcomes, including total body bone mineral density and bone mineral content and spine bone mineral density. We evaluated effect modification by HIV and sex.

RESULTS

The analysis cohort consisted of 143 HIV-neg and 236 HIV-pos, of whom 55% were black non-Hispanic and 53% were male. Ages ranged from 7 to < 25 years. Half of the children/youth were at Tanner stage 1 and 20% at Tanner 5. Fat mass was more strongly positively correlated with bone mass in HIV-neg than HIV-pos children/youth and these relationships were more evident for total body bone than spine outcomes. Within HIV strata, fat mass and bone were more correlated in female than male children/youth. The relationship between lean mass and bone varied by sex, but not by HIV status.

CONCLUSIONS

HIV disease diminishes the positive relationship of greater fat mass on bone mass in children/youth. Disruptions in body fat distribution, which are common in HIV disease, may have an impact on bone accretion during pubertal development.

Relationship between ultrasound bone parameters, lung function, and body mass index in healthy student population

Low bone mineral density has been reported in paediatric and adult patients with different lung diseases, but limited data are available on the association between lung function and bone density in a healthy young population. We explored the predictors of association between bone mass and pulmonary function in healthy first-year university students, focusing on body mass index (BMI). In this cross-sectional study we measured bone density with ultrasound and lung function with spirometry in 370 university students (271 girls and 99 boys). Information on lifestyle habits, such as physical activity, smoking, and alcohol consumption were obtained with a questionnaire. All lung function and bone parameters were significantly higher in boys than in girls (P<0.001). Underweight students had a significantly lower forced vital capacity (FVC%) (P=0.001 girls; P=0.012 boys), while overweight students had a significantly higher FVC% than normal weight students (P=0.024 girls; P=0.001 boys). BMI significantly correlated with FVC% (P=0.001) and forced expiratory volume in 1 second (FEV1 %) in both genders (P=0.001 girls; P=0.018 boys) and with broadband ultrasound attenuation (BUA) in boys. There were no significant associations between any of the bone and lung function parameters either in boys or girls. The most important determinant of lung function and ultrasound bone parameters in our study population was body mass index, with no direct association between bone density and lung function.

The relationship between adiposity and bone density in U.S. children and adolescents

Objective

In adults, obesity has been associated with several health outcomes including increased bone density. Our objective was to evaluate the association between percent body fat and fat mass with bone mineral density (BMD) in a nationally representative population of children and adolescents.

Study design

A total of 8,348 participants 8–18 years of age from the National Health and Nutrition Examination Survey (NHANES) 1999–2006 had whole body DXA scans performed. We conducted linear regressions to examine the relationship between percent body fat and fat mass with outcome variables of total body, pelvic and lumbar spine areal BMD (aBMD), controlling for lean body mass and assessing for gender and race/ethnicity interactions.

Results

We found evidence of gender and race/ethnicity interactions with percent body fat and total fat mass for the different BMD areas. Generally, there were decreases in total body aBMD (p<0.001) and lumbar spine aBMD (p<0.001) with increasing percent body fat and total fat mass, with less consistent patterns for pelvic aBMD.

Conclusion

Our findings of regional differences in the relationship of adiposity to aBMD in children and adolescents with significant interactions by gender and race/ethnicity emphasizes the need for further investigations to understand the impact of adiposity on bone health outcomes.

Adipokines may mediate the relationship between resting metabolic rates and bone mineral densities in obese women

The researchers sought to test the possible link between resting metabolic rate and bone mineral density through four adipokines. Participants with lower resting metabolic rate (RMR) per kilogram demonstrated higher total bone mineral density (BMD), total T-score, and total Z-score. Omentin-1 had a mediatory effect on the relationship between RMR/kg of body weight and bone parameters.

INTRODUCTION

The previous results of studies regarding the links between obesity and bone health are controversial. For this reason, the researchers sought to test the possible link between RMR and BMD through the following four adipokines: vaspin, retinol binding protein 4, angiopoietin-like 6 (ANGPL6), and omentin-1.

METHODS

We enrolled 312 obese Iranian women (30 ≤ body mass index <40) in this cross-sectional study. In order to examine the association of serum adipokine levels with RMR and BMD, the participants were grouped based on RMR per body weight. Body composition, dietary intake, bone mineral density, and resting metabolic rate were assessed in all participants. Serum adipokine levels were quantified by the enzyme-linked immunosorbent assay (ELISA) method.

RESULTS

Low levels of RMR/kg were strongly associated with higher weight, body mass index, fat mass, and visceral fat levels. In fact, participants with an RMR/kg of body weight <20 kcal/24 h/kg were more obese (p < 0.05). Another noteworthy finding was that participants with lower RMR/kg demonstrated higher total BMD, total T-score, and total Z-score. Our results showed that omentin-1 had a mediatory effect on the relationship between RMR per kilogram of body weight and bone parameters (p < 0.05). Nevertheless, other adipokines such as vaspin, retinol-binding protein 4 (RBP4), and ANGPL6 did not affect the relationship between RMR and BMD (p > 0.05).

CONCLUSIONS

The inhibitory effect of omentin-1 on TNF-alpha seems to be able to reduce the amount of circulating leptin as adipokine, affecting energy expenditure and improving bone loss induced by estrogen deficiency and controlled effect of RMR on BMD.

Visceral fat measured by DXA is associated with increased risk of non-spine fractures in nonobese elderly women: a population-based prospective cohort analysis from the São Paulo Ageing & Health (SPAH) Study

The present study investigates the relationship between visceral fat measured by dual-energy X-ray absorptiometry (DXA) and the incidence of non-spine fractures in community-dwelling elderly women. We demonstrated a potential negative effect of visceral fat on bone health in nonobese women.

INTRODUCTION

The protective effect of obesity on bone health has been questioned because visceral fat has been demonstrated to have a deleterious effect on bone. The aim of this study was to investigate the association of visceral fat measured by DXA with the incidence of non-spine fractures in community-dwelling elderly women.

METHODS

This longitudinal prospective population-based cohort study evaluated 433 community-dwelling women aged 65 years or older. A specific clinical questionnaire, including personal history of a fragility fracture in non-spine osteoporotic sites, was administered at baseline and after an average of 4.3 years. All incidences of fragility fractures during the study period were confirmed by affected-site radiography. Visceral adipose tissue (VAT) was measured in the android region of a whole-body DXA scan.

RESULTS

The mean age was 72.8 ± 4.7 years, and 28 incident non-spine osteoporotic fractures were identified after a mean follow-up time of 4.3 ± 0.8 years. According to the Lipschitz classification for nutritional status in the elderly, 38.6 % of women were nonobese (BMI ≤ 27 kg/m²) and 61.4 % were obese/overweight. Logistic regression models were used to estimate the relationship between VAT and non-spine fractures in elderly women. After adjusting for age, race, previous fractures, and BMD, VAT (mass, area, volume) had a significant association with the incidence of non-spine fractures only in nonobese elderly women (VAT mass: OR, 1.42 [95 % CI, 1.09-1.85; p = 0.010]; VAT area: OR, 1.19 [95 % CI, 1.05-1.36; p = 0.008]; VAT volume: OR, 1.40 [95 % CI, 1.09-1.80; p = 0.009]).

CONCLUSION

This study suggests a potential negative effect of visceral adiposity on bone health in nonobese women.

BMI and BMD: The Potential Interplay between Obesity and Bone Fragility

Recent evidence demonstrating an increased fracture risk among obese individuals suggests that adipose tissue may negatively impact bone health, challenging the traditional paradigm of fat mass playing a protective role towards bone health. White adipose tissue, far from being a mere energy depot, is a dynamic tissue actively implicated in metabolic reactions, and in fact secretes several hormones called adipokines and inflammatory factors that may in turn promote bone resorption. More specifically, Visceral Adipose Tissue (VAT) may potentially prove detrimental. It is widely acknowledged that obesity is positively associated to many chronic disorders such as metabolic syndrome, dyslipidemia and type 2 diabetes, conditions that could themselves affect bone health. Although aging is largely known to decrease bone strength, little is yet known on the mechanisms via which obesity and its comorbidities may contribute to such damage. Given the exponentially growing obesity rate in recent years and the increased life expectancy of western countries it appears of utmost importance to timely focus on this topic.

Associations of anthropometric measures on breast cancer risk in pre- and postmenopausal women--a case-control study

Background

The type of silhouette and quantity of fat tissue are correlated with hormonal imbalance which plays a substantial role in breast carcinogenesis. The goal of the study was to investigate the association between various anthropometric characteristics and breast cancer risk.

Methods

Detailed anthropometric assessment was conducted on 487 women of whom 193 had diagnosed breast cancer and were consecutive patients in the Oncology Center, Cracow, Poland between 2002 and 2004. Measurements were divided into four categories: overall body size (body mass index [BMI], waist circumference [WC], waist-hip ratio [WHR]), regional body sizes (skinfold thicknesses, circumferences), thickness of the skeleton (widths, chest diameters), and body proportions. Additionally, results were analyzed in regard to menopausal status. Differences between groups were assessed using Student’s t test and Mann-Whitney’s test. Models of logistic regression for selected data were built to estimate the odds ratio. Results were considered statistically significant when the P value was less than 0.05.

Results

The BMI in both groups was negatively associated with the risk of cancer. Among premenopausal women, WHR increased the risk of breast cancer (WHR > 0.83, OR, 2.72; 95 % CI, 1.01–7.27). Anthropometric indices of hip-to-shoulder ratio in postmenopausal (≥84.2 mm, OR, 0.02; 95 % CI, 0.01–0.11) and trunk-to-height ratio in both premenopausal women (≥32.76, OR, 0.09; 95 % CI, 0.03–0.28) and postmenopausal women (≥32.76, OR, 0.13; 95 % CI, 0.05–0.33) were strongly related to a decreased risk of breast cancer. Thicknesses of the triceps and subscapular skinfolds increased the risk of breast cancer.

Conclusions

Women with breast cancer present with an obese type of silhouette with a specific concentration of fat tissue in the central and upper parts of the body.

Dietary restrictions, bone density, and bone quality

Caloric restriction (CR), protein restriction (PR), and specific amino acid restriction (e.g., methionine restriction (MR)) are different dietary interventions that have been confirmed with regard to their comprehensive benefits to metabolism and health. Based on bone densitometric measurements, weight loss induced by dietary restriction is known to be accompanied by reduced areal bone mineral density, bone mass, and/or bone size, and it is considered harmful to bone health. However, because of technological advancements in bone densitometric instruments (e.g., high-resolution X-ray tomography), dietary restrictions have been found to cause a reduction in bone mass/size rather than volumetric bone mineral density. Furthermore, when considering bone quality, bone health consists of diverse indices that cannot be fully represented by densitometric measurements alone. Indeed, there is evidence that moderate dietary restrictions do not impair intrinsic bone material properties, despite the reduction in whole-bone strength because of a smaller bone size. In the present review, we integrate research evidence from traditional densitometric measurements, metabolic status assays (e.g., energy metabolism, oxidative stresses, and inflammatory responses), and biomaterial analyses to provide revised conclusions regarding the effects of CR, PR, and MR on the skeleton.

Greater Adipose Tissue Distribution and Diminished Spinal Musculoskeletal Density in Adults With Cerebral Palsy

OBJECTIVES

To examine differences in adipose tissue distribution, lumbar vertebral bone mineral density (BMD), and muscle attenuation in adults with and without cerebral palsy (CP), and to determine the associations between morphologic characteristics.

DESIGN

Cross-sectional, retrospective analyses of archived computed tomography scans.

SETTING

Clinical treatment and rehabilitation center.

PARTICIPANTS

Adults (N=352) with CP (age, 38.8±14.4y; body mass, 61.3±17.1kg; Gross Motor Function Classification System levels, I-V) and a matched cohort of neurotypical adults. Of the 41 adults with CP included in the study, 10 were not matchable because of low body masses.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Computed tomography scans were assessed for visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) areas, psoas major area and attenuation in Hounsfield units (Hu), and cortical and trabecular BMDs.

RESULTS

Adults with CP had lower cortical (β=-63.41 Hu, P<.001) and trabecular (β=-42.24 Hu, P<.001) BMDs and psoas major areas (β=-374.51mm(2), P<.001) and attenuation (β=-9.21 Hu, P<.001) after controlling for age, sex, and body mass. Adults with CP had greater VAT (β=3914.81mm(2), P<.001) and SAT (β=4615.68mm(2), P<.001). Muscle attenuation was significantly correlated with trabecular (r=.51, P=.002) and cortical (r=.46, P<.01) BMD, whereas VAT was negatively associated with cortical BMD (β=-.037 Hu/cm(2), r(2)=.13, P=.03).

CONCLUSIONS

Adults with CP had lower BMDs, smaller psoas major area, greater intermuscular adipose tissue, and greater trunk adiposity than neurotypical adults. VAT and cortical BMD were inversely associated.

The Effects of Eight-Month Physical Activity Intervention on Vigilance Performance in Adult Obese Population

We aim to analyze the effects of an 8-month physical activity intervention on cardiorespiratory fitness, body mass index (BMI), and vigilance performance in an adult obese population. We conducted an 8-month physical activity intervention based on dance and rhythmic activities. The weekly frequency was 2 sessions of 1 hr per day. Training sessions were divided into 3 phases: a 10-min warm-up, 40 min of dance and rhythmic activities, and 10 min to cool-down. To assess cardiorespiratory fitness, participants performed a modified version of the 6-min walk test from the Senior Fitness Test battery (Larsson & Mattsson, 2001; Rikli & Jones, 1999). Vigilance performance was measured by means of the psychomotor vigilance task (PVT). Two measurements were performed immediately before and after the intervention. The results revealed that participants improved their cardiorespiratory fitness, BMI, and vigilance performance after the intervention. All in all, findings contribute new empirical evidence to the field that investigates the benefits of physical activity intervention on cognitive processes in obese population.

A cohort study of 4,190 patients treated with low-intensity pulsed ultrasound (LIPUS): findings in the elderly versus all patients

BACKGROUND

Patient age is one of many potential risk factors for fracture nonunion. Our hypothesis is that older patients (≥ 60) with fracture risk factors treated with low-intensity pulsed ultrasound (LIPUS) have similar heal rate (HR) to the population as a whole. We evaluate the impact of age in conjunction with other risk factors on HR in LIPUS-treated patients with fresh fracture (≤ 90 days old).

METHODS

The Exogen Bone Healing System is a LIPUS device approved in 1994 to accelerate healing of fresh fracture. After approval, the FDA required a Post-Market Registry to assess performance. Patient data collected from October 1994 until October 1998 were individually reviewed and validated by a registered nurse. Four distinct data elements were required to report a patient: date fracture occurred; date treatment began; date treatment ended; and a dichotomous outcome of healed v. failed, by clinical and radiological criteria. Data were used to calculate two derived variables; days to treatment (DTT) and days on treatment (DOT). Every validated fresh fracture patient with DTT, DOT, and outcome is reported.

RESULTS

The validated registry had 5,765 patients with fresh fracture; 73% (N = 4,190) are reported, while 13% of patients were lost to follow-up, 11% withdrew or were non-compliant, and 3% died or are missing outcome. Among treatment-compliant patients, HR was 96.2%. Logistic estimates of the odds ratio for healing are equivalent for patients age 30 to 79 years and all age cohorts had a HR > 94%. Open fracture, current smoking, diabetes, vascular insufficiency, osteoporosis, cancer, rheumatoid arthritis, and prescription NSAIDs all reduced HR, but older patients (≥ 60) had similar HRs to the population as a whole. DTT was significantly shorter for patients who healed (p < 0.0001).

CONCLUSIONS

Comorbid conditions in conjunction with aging can reduce fracture HR. Patients with fracture who used LIPUS had a 96% HR, whereas the expected HR averages 93%. Time to treatment was significantly shorter among patients who healed (p < 0.0001), suggesting that it is beneficial to begin LIPUS treatment early. Older patients (≥ 60) with fracture risk factors treated with LIPUS exhibit similar heal rates to the population as a whole.

Visceral adiposity is negatively associated with bone density and muscle attenuation

BACKGROUND

The storage of adipose tissue in ectopic compartments is a hallmark attribute linking greater body mass index (BMI) with cardiometabolic diseases. Despite ample evidence to confirm that increased visceral adipose tissue (VAT) deposition occurs with obesity, the interrelations between altered fat partitioning and regional muscle and bone quality are less well understood.

OBJECTIVE

We examined the association between adiposity and spinal muscle and bone quality across a large, heterogeneous cohort of adults.

DESIGN

We identified 8833 thoracic or abdominal computed tomography scans from patients in the University of Michigan Health System who were aged 18-64.9 y. We measured trabecular bone densities, cortical bone densities, VAT areas, and subcutaneous adipose tissue (SAT) areas at vertebral levels T7 to L5. Psoas muscle attenuation (an indicator of fat infiltration in muscle) was measured at the L4 level.

RESULTS

Muscle attenuation as well as trabecular and cortical bone densities revealed negative correlations with BMI, SAT, and VAT. The correlation between BMI and psoas attenuation was -0.321, between BMI and the density of cortical bone was -0.250, and between BMI and trabecular bone was -0.143 (all P < 0.001). However, correlations between VAT and lower muscle attenuation were stronger as were those between VAT and lower bone densities. Inverse correlations between VAT and densities of psoas muscle and cortical and trabecular bone were -0.460, -0.407, and -0.434, respectively (P < 0.001). Even after adjustment for age, sex, and BMI, partial correlations between VAT, muscle attenuation, and bone densities remained significant at -0.250, -0.119, and -0.216, respectively (P < 0.001).

CONCLUSIONS

Contrary to previous reports that high body mass is associated with increased bone quality, our data show a significant negative association between BMI and muscle and bone densities, suggesting fat infiltration into these tissues. More importantly, correlations between VAT and decreased bone and muscle densities remained statistically significant even after adjustment for age, sex, and BMI.

NADPH oxidases in bone homeostasis and osteoporosis

Bone formation and degradation are perfectly coordinated. In case of an imbalance of these processes diseases occur associated with exaggerated formation of new bone or bone loss as in osteoporosis. Most studies investigating osteoporosis either focus on osteoblast or osteoclast function and differentiation. Both processes have been suggested to be affected by reactive oxygen species (ROS). Besides a potentially harmful role of ROS, these small molecules are important second messengers. The family of NADPH oxidases produces ROS in a controlled and targeted manner, to specifically regulate signal transduction. This review will highlight the role of reactive oxygen species in bone cell differentiation and bone-loss associated disease with a special focus on osteoporosis and NADPH oxidases as specialized sources of ROS.

Estimated lean mass and fat mass differentially affect femoral bone density and strength index but are not FRAX independent risk factors for fracture

Although increasing body weight has been regarded as protective against osteoporosis and fractures, there is accumulating evidence that fat mass adversely affects skeletal health compared with lean mass. We examined skeletal health as a function of estimated total body lean and fat mass in 40,050 women and 3600 men age ≥50 years at the time of baseline dual-energy X-ray absorptiometry (DXA) testing from a clinical registry from Manitoba, Canada. Femoral neck bone mineral density (BMD), strength index (SI), cross-sectional area (CSA), and cross-sectional moment of inertia (CSMI) were derived from DXA. Multivariable models showed that increasing lean mass was associated with near-linear increases in femoral BMD, CSA, and CSMI in both women and men, whereas increasing fat mass showed a small initial increase in these measurements followed by a plateau. In contrast, femoral SI was relatively unaffected by increasing lean mass but was associated with a continuous linear decline with increasing fat mass, which should predict higher fracture risk. During mean 5-year follow-up, incident major osteoporosis fractures and hip fractures were observed in 2505 women and 180 men (626 and 45 hip fractures, respectively). After adjustment for fracture risk assessment tool (FRAX) scores (with or without BMD), we found no evidence that lean mass, fat mass, or femoral SI affected prediction of major osteoporosis fractures or hip fractures. Findings were similar in men and women, without significant interactions with sex or obesity. In conclusion, skeletal adaptation to increasing lean mass was positively associated with BMD but had no effect on femoral SI, whereas increasing fat mass had no effect on BMD but adversely affected femoral SI. Greater fat mass was not independently associated with a greater risk of fractures over 5-year follow-up. FRAX robustly predicts fractures and was not affected by variations in body composition.

The relationship between bioactive components in breast milk and bone mass in infants

Human breast milk (HBM) contains numerous bioactive components, recently shown to be associated with growth and body composition in breastfed offspring. Reciprocity in adipogenic and osteogenic pathways suggests bone mass may also be influenced by these components. The association between bioactive components found in HBM and bone mineral content (BMC), to our knowledge, is unknown. The purpose of this proof-of-principle study was to evaluate the association between specific bioactive components in HBM in exclusively breastfed infants and skeletal health in the first 6 months of life and examine potential gender differences in these associations. Thirty-five mother-infant dyads were followed from 1 to 6 months. The contents of a single breast expression were used for analyses of bioactive components (insulin, glucose, leptin, interleukin-6 and tumor necrosis factor-α (TNFα), whereas BMC was evaluated by dual-energy X-ray absorptiometry. In the total sample, there was a positive association between TNFα and BMC at 1 (P=0.004) and 6 months (P=0.007). When stratified by sex, females exhibited a positive association between BMC and glucose and an inverse relationship between BMC and TNF-α at 1 month with TNF-α strengthening (P=0.006) at 6 months. In males, at 6 months a positive relationship between BMC and HBM glucose and an inverse relationship with HBM leptin were observed with no associations observed at 1 month. Although preliminary, the associations between bioactive components in HBM highlight the importance HBM has on bone accretion. It is critically important to identify factors in HBM that contribute to optimal bone health.

Divergent effects of obesity on fragility fractures

Obesity was commonly thought to be advantageous for maintaining healthy bones due to the higher bone mineral density observed in overweight individuals. However, several recent studies have challenged the widespread belief that obesity is protective against fracture and have suggested that obesity is a risk factor for certain fractures. The effect of obesity on fracture risk is site-dependent, the risk being increased for some fractures (humerus, ankle, upper arm) and decreased for others (hip, pelvis, wrist). Moreover, the relationship between obesity and fracture may also vary by sex, age, and ethnicity. Risk factors for fracture in obese individuals appear to be similar to those in nonobese populations, although patterns of falling are particularly important in the obese. Research is needed to determine if and how visceral fat and metabolic complications of obesity (type 2 diabetes mellitus, insulin resistance, chronic inflammation, etc) are causally associated with bone status and fragility fracture risk. Vitamin D deficiency and hypogonadism may also influence fracture risk in obese individuals. Fracture algorithms such as FRAX^® might be expected to underestimate fracture probability. Studies specifically designed to evaluate the antifracture efficacy of different drugs in obese patients are not available; however, literature data may suggest that in obese patients higher doses of the bisphosphonates might be required in order to maintain efficacy against nonvertebral fractures. Therefore, the search for better methods for the identification of fragility fracture risk in the growing population of adult and elderly subjects with obesity might be considered a clinical priority which could improve the prevention of fracture in obese individuals.

Weight loss intervention trials in women with breast cancer: a systematic review

Obesity has been associated with poor health outcomes in breast cancer survivors. Thus, weight loss is recommended for overweight and obese survivors. We systematically reviewed studies (published up to July 2013) that evaluated behaviourally based, weight loss interventions in women with breast cancer exclusively. Completed randomized trials, single-arm trials and ongoing trials were reviewed. Within-group and between-group differences for weight loss were extracted, as was data on secondary outcomes, i.e. clinical biomarkers, patient-reported outcomes, adverse events. Ten completed randomized trials, four single-arm trials and five ongoing trials were identified. Statistically significant within-group weight loss was observed over periods of 2 to 18 months in 13 of the 14 trials, with six randomized and two single-arm trials observing mean weight loss ≥5%. Clinical biomarkers, psychosocial and patient-reported outcomes were measured in a small number of studies. No serious adverse events were reported. Only two trials assessed maintenance of intervention effects after the end-of-intervention and none reported on cost-effectiveness. The studies included in this review suggest that weight loss is feasible to achieve and is safe in women following treatment for breast cancer. Future studies should assess (and be powered for) a range of biomarker and patient-reported outcomes, and be designed to inform translation into practice.

Ketogenic diet for obesity: friend or foe?

Obesity is reaching epidemic proportions and is a strong risk factor for a number of cardiovascular and metabolic disorders such as hypertension, type 2 diabetes, dyslipidemia, atherosclerosis, and also certain types of cancers. Despite the constant recommendations of health care organizations regarding the importance of weight control, this goal often fails. Genetic predisposition in combination with inactive lifestyles and high caloric intake leads to excessive weight gain. Even though there may be agreement about the concept that lifestyle changes affecting dietary habits and physical activity are essential to promote weight loss and weight control, the ideal amount and type of exercise and also the ideal diet are still under debate. For many years, nutritional intervention studies have been focused on reducing dietary fat with little positive results over the long-term. One of the most studied strategies in the recent years for weight loss is the ketogenic diet. Many studies have shown that this kind of nutritional approach has a solid physiological and biochemical basis and is able to induce effective weight loss along with improvement in several cardiovascular risk parameters. This review discusses the physiological basis of ketogenic diets and the rationale for their use in obesity, discussing the strengths and the weaknesses of these diets together with cautions that should be used in obese patients.