The Association between Fat Mass, Lean Mass and Bone Mineral Density in Premenopausal Women in Korea: A Cross-Sectional Study

Association between normal-weight obesity and bone mineral density in older Korean adults: A population-based cross-sectional study

The effects of normal-weight obesity, which is defined as having a high level of body fat despite a normal body mass index, on the health of bones in older adults are poorly understood. This cross-sectional study examined the relationship between normal-weight obesity and bone mineral density in Korean adults aged 50 years or more (2815 men and 2744 women) from the 2008-2011 Korea National Health and Nutrition Examination Surveys. Between the ages of 50 and 69 years, individuals with normal-weight obesity had a higher risk of low bone mineral density (odds ratio = 1.596, 95 % confidence interval = 1.189-2.141, p = 0.002) compared with individuals with normal-weight non-obesity. However, no significant association between normal-weight obesity and bone mineral density was observed among people between the ages of 70 and 89 years. The study findings support the clinical significance of normal-weight obesity as a proxy biomarker to identify in primary care settings people who are at increased risk of developing osteoporosis at an early stage of aging.

Elevated circulating levels of IL-34 are strongly associated with osteoporosis

In this cross-sectional study, we observed a strong, age-independent association of circulating interleukin-34 (IL-34) levels with osteoporosis.

PURPOSE

The reported capacity of IL-34 to induce and enhance osteoclastogenesis suggests its potential involvement in the pathogenesis of osteoporosis. Our study aimed to evaluate whether there is an association between IL-34 expression and osteoporosis.

METHODS

We enrolled 30 women with osteoporosis and 230 age-matched non-osteoporotic women as a control group. Osteoporosis diagnosis was based on dual-energy X-ray absorptiometry (DXA) of the lumbar spine and femoral neck. Body composition parameters were assessed by the bioimpedance method. Plasma IL-34 levels were measured by ELISA.

RESULTS

In comparison with the control group, the mean plasma IL-34 levels were significantly higher in osteoporotic women (164.61 ± 36.40 pg/ml vs. 665.43 ± 253.67 pg/ml, p = 0.0002), whereas basal metabolic rate (BMR) was significantly lower (1422.03 ± 6.80 kcal vs. 1339.39 ± 17.52 kcal, p = 0.00007). Both variables remained statistically significant after adjustment for age (p < 0.001). We did not observe correlations between plasma IL-34 levels and body composition parameters in osteoporotic and control groups. Multiple logistic regression analysis with osteoporosis status as a dependent variable clearly showed that age, BMR and IL-34 levels were independently and significantly associated with osteoporosis. The calculated odds ratios (OR) were 1.66 (95% CI = 1.16-2.38) for IL-34 levels and 0.22 (95% CI = 0.07-0.65) for BMR.

CONCLUSION

The significant (fourfold) elevation of IL-34 plasma levels in osteoporosis patients suggests that circulating IL-34 could be used as a biomarker for osteoporosis.

Influence of Muscle Mass and Strength on Bone Mineralisation with Consideration of Sclerostin Concentration

Osteoporosis is a disease characterised by a reduction in bone strength due to increased porosity and impaired mineralisation. In our study, we investigated whether muscle strength and mass exert a significant effect on bone mineral density in young adult women. We also tested whether sclerostin can be used as an indicator in the assessment of bone mineralisation. The study included 111 patients. All patients had their bone mineral density determined in the L1-L4 section of the lumbar spine and in the whole skeleton. The parameters of fat mass (FM), lean body mass (LBM) and visceral fat mass (VF) were also determined. Metabolic activity of osteocytes was assessed by measuring the serum sclerostin concentration. There was a statistically significant association of both hands' muscle strength with all parameters expressing bone mineralisation. A statistically significant relationship was also obtained between BMD L1-L4 and the body mass components (FM, LBM). Sclerostin levels in the study did not differ between groups with normal and reduced bone mineral density. Muscle strength assessment may be a potential exponent of reduced bone mineral density, also used clinically in young adult women. The utility of sclerostin in the clinical assessment of bone mineralisation has not been demonstrated.

Association of Short-Term Changes in Menstrual Frequency, Medication Use, Weight and Exercise on Bone Mineral Density in College-Aged Women

To evaluate if experiencing a short-term exposure (18-months) to factors such as menstrual irregularities, dieting, changes in exercise or body weight, and medication usage is associated with bone mineral density (BMD) in college-aged females. A retrospective survey assessing health behaviors during a recent 18-month time period and a DXA scan were completed in 641 females. A total of 45.5% of participants reported amenorrhea during the 18-month time period. Those who experienced amenorrhea had lower femoral neck BMD (p = 0.018), trochanter (p = 0.018) and spine BMD (p = 0.022) compared to eumenorrheic women. Lifetime oral contraceptive usage longer than six months was negatively associated with BMD at femoral neck (p = 0.018) and total hip (p = 0.021). Women who lost weight trended towards having the lowest BMD at all sites compared to women who gained weight. Following a very-low calorie diet during the time period was negatively correlated with spine BMD (p = 0.001). Time spent in vigorous and very vigorous activity was weakly correlated with some hip BMD sites but time spent in extremely vigorous activity was not. In conclusion, females who experienced weight loss, amenorrhea, or a very low-calorie diet within an 18-month period of time in young adulthood had lower BMD. Additionally, oral contraceptive usage for longer than six months during their lifetime was associated with lower BMD.

The Relationship Between Bone Mineral Density and Body Composition Among Qatari Women With High Rate of Obesity: Qatar Biobank Data

Studies have reported inconsistent results for the relationship between body composition and bone mineral density (BMD) among women, especially those with a high rate of obesity. This study aims to examine the association between BMD and body composition among Qatari women. A cross-sectional study, using data from the Qatar Biobank (QBB), was conducted on 2,000 Qatari women aged 18 and over. Measurements were taken by dual-energy X-ray absorptiometry (DEXA) for body composition [visceral fat and android fat (AF)], gynoid fat (GF), trunk fat, total fat mass (TFM), total lean mass (LM) and bone mineral density (BMD), including the lumber spine, neck, femur and total body. The participants were divided into groups of normal and low BMD, based on their T-score. Non-linear regression analysis using the restricted cubic spline method was performed according to the T-score of the total BMD for the fat mass variables. Women with a low BMD (T-score <-1) had significantly lower body composition indicators. LM was positively correlated with BMD at the spine (r = 0.29, p < 0.001), neck (r = 0.32, p < 0.001), and femur (r = 0.28, p < 0.001), as well as total BMD (r = 0.29, p < 0.001) and T-score (r = 0.31, p < 0.001), while the correlatio between TFM and BMD was negative and weak (r = -0.05, <0.017). Results of the non-linear regression indicated that components of fat distribution (TFM, AF, GF and trunk fat) were positively associated with total body T-score. In the adjusted non-liner regression, only a slight increase in T-score was recorded with an increase in FM. The association between FM and BMD was non-linear, suggesting that FM may not be a strong protector of bones among women with high rate of obesity.

Association of androgen excess and bone mineral density in women with classical congenital adrenal hyperplasia with 21-hydroxylase deficiency

The relationship between androgen excess and bone health in patients with congenital adrenal hyperplasia (CAH) with 21-hydroxylase (21-OH) deficiency is not fully understood. This study demonstrated positive correlations between androgen hormones and bone mineral density (BMD) in CAH women with 21-OH deficiency.

PURPOSE

This study aims to assess BMD and its association with androgen excess in women with CAH.

METHODS

We enrolled 92 women with CAH with 21-OH deficiency and retrospectively reviewed their clinical features, hormone concentrations, body composition, glucocorticoid (GC) dose, and BMD.

RESULTS

BMD was not different according to the subtypes of CAH. BMD at the lumbar spine was lower in women with CAH with regular menstruation than those with irregular menstruation (1.081 vs. 1.165 g/cm², P < 0.05). BMD was lower in women with CAH with 17-hydroxyprogesterone (17-OHP) < 10 ng/mL than in those with ≥ 10 ng/mL (lumbar spine, 1.019 vs. 1.150 g/cm²; femur neck, 0.806 vs. 0.899 g/cm²; total hip, 0.795 vs. 0.943 g/cm²; all P < 0.05). After adjusting for age and BMI in correlation analyses, testosterone concentrations were positively correlated with lumbar spine, femur neck, and total hip BMD (r = 0.46, r = 0.38, and r = 0.35, respectively; all P < 0.05), while 17-OHP was positively correlated with lumbar spine BMD (r = 0.38, P < 0.01). In subgroup analysis, 17-OHP was positively correlated with BMD (lumbar spine, r = 0.22; femur neck, r = 0.22; total hip, r = 0.24; all P < 0.05) only in the group with a total cumulative dose of GC ≥ 156.0 g/m².

CONCLUSION

Androgen excess may have a protective effect on BMD in women with classic CAH and high cumulative doses of GC.

Association between body mass index, bone bending strength, and BMD in young sedentary women

The rationale was to determine whether body mass index (BMI) is a predictor of bone bending strength and bone mineral density (BMD) in young sedentary women. Results show that BMI is not a predictor of bone bending strength and that young women with low BMI also have low BMD.

INTRODUCTION

The purpose of this study was to determine whether body mass index (BMI) is a predictor of tibial or ulnar bending strength and bone mineral density (BMD) in sedentary women.

METHODS

Sedentary women (n = 34), age 19-27 years, with low BMI (LBMI < 18.5 kg/m², n = 16), and normal or high BMI (NHBMI between 18.5 and 29.9 kg/m², n = 18) participated as study subjects. Study outcomes included tibial and ulnar bending strength (EI in Nm²) using a non-invasive mechanical response tissue analyzer (MRTA); BMD and bone mineral content (BMC) of the whole body (WB), femoral neck (FN), total hip (TH), lumbar spine 1-4 (LS1-4), and ulna; and bone turnover biomarkers.

RESULTS

The LBMI group have lower (p < 0.01) body weight [group difference (Δ) = 32.0%], lean mass (LM) (Δ = 23.1%), fat mass (FM) (Δ = 77.2%), and tibial bending strength (Δ = 22.0%), compared to the NHBMI. The LBMI group also have lower (all p < 0.025) BMC in WB (Δ = 19.9%), FN (Δ = 20.1%) and TH (Δ = 19.0%), compared to the NHMBI, not in BMD results. Multivariate regression analysis shows that significant predictors of tibial bending strength are tibia length (adjusted R² = .341), age (adjusted R² = .489), ulna BMD (adjusted R² = .536), and LM (adjusted R² = .580). BMI was positively correlated with tibial EI (p < 0.05), height, weight, FM, LM, body fat% (all p < 0.01), and BMD of WB, FN, TH, and LS 1-4 (p < 0.05 or < 0.01).

CONCLUSIONS

Our results show that BMI is not a significant predictor of tibial or ulnar bending strength in young sedentary women.

The role of FSH in body composition in hematopoietic cell transplant recipients

BACKGROUND

Childhood cancer survivors who received a hematopoietic cell transplantation (HCT) are at increased risk for follicle-stimulating hormone (FSH) abnormalities, which may have a significant negative impact on bone health and body composition. This study's purpose was to examine FSH and body composition in HCT recipients, non-HCT recipients and healthy controls.

METHODS

The study included HCT recipients (n = 24), non-HCT recipients (n = 309), and a control group of healthy siblings (n = 211) all aged 9-18 years. A fasting blood sample was collected to measure FSH. All participants underwent a dual X-ray absorptiometry scan to assess total and regional percent fat, lean mass (LM), fat mass (FM), bone mineral content (BMC), bone mineral density (BMD), and visceral adipose tissue (VAT) mass.

RESULTS

FSH was significantly higher in HCT recipients compared to non-HCT recipients and healthy controls. HCT recipients had significantly lower total body weight, total LM, arm and leg LM, BMC and BMD compared to non-HCT recipients and healthy controls (p < .05). Non-HCT recipients had significantly higher total, trunk, android, gynoid, arm and leg FM compared to healthy controls. Also, healthy controls had significantly lower VAT mass compared to non-HCT recipients.

CONCLUSIONS

This study's results show that HCT recipients have significant reductions in BMD, worse body composition, and abnormal FSH levels compared to non-HCT recipients and healthy controls.

Association between body mass index and fragility fracture in postmenopausal women: a cross-sectional study using Korean National Health and Nutrition Examination Survey 2008-2009 (KNHANES IV)

BACKGROUND

The present study examined the relationship between body mass index (BMI) and the risk for fragility fractures in postmenopausal Korean women.

METHODS

Among subjects who participated in the 4th Korea National Health and Nutrition Examination Survey (2008-2009), 2114 women ≥ 40 years of age were included. BMI was based on standards set by the Korean Society for the Study of Obesity, as follows: < 18.5 kg/m², underweight; 18.5 ≤ to < 25 kg/m², normal weight; and ≥ 25 kg/m², obese. Subjects were also divided into three groups according to the location of fragility fracture: spine, hip, or wrist.

RESULTS

The mean (± SD) rate of fragility fracture was significantly different among the three groups: 5.9 ± 2.9% (underweight), 1.1 ± 0.3% (normal weight), and 3.0 ± 0.7% (obese) (p = 0.001). After correcting for age, family history, and treatment history of osteoporosis and rheumatoid arthritis, smoking and drinking status, and level of exercise, multivariable regression analysis revealed that the odds ratio for fragility fracture in the underweight group was 5.48 [95% confidence interval (CI) 1.80-16.73] and 3.33 (95% CI 1.61-6.87) in the obese group. After subdividing fragility fractures into vertebral and non-vertebral, the odds ratio for vertebral fracture in the underweight group was 5.49 (95% CI 1.31-23.09) times higher than that in the normal weight group; in the obese group, the non-vertebral fracture odds ratio was 3.87 (95% CI 1.45-10.33) times higher. Analysis of non-vertebral fractures in the obese group revealed an odds ratio for fracture 22.05 (95% CI 1.33-365.31) times higher for hip fracture and 3.85 (95% CI 1.35-10.93) times higher for wrist fracture.

CONCLUSIONS

Obesity and underweight increased the risk for fragility fractures in postmenopausal Korean women.

Lean mass and peak bone mineral density

Objectives

The association between body composition parameters and peak bone mineral density is not well documented. The aim of this study is to assess the relative contributions of lean mass and fat mass on peak bone mineral density (BMD).

Methods

The study involved 416 women and 334 men aged between 20 and 30 years who were participants in the population-based Vietnam Osteoporosis Study. Whole body composition parameters (eg, fat mass and lean mass) and BMD at the lumbar spine and femoral neck were measured by dual-energy X-ray absorptiometry. The association between lean mass and fat mass and BMD was analyzed by the linear regression model using the Least Absolute Shrinkage and Selection Operator (LASSO).

Results

Peak BMD in men was higher than women, and the difference was more pronounced at the femoral neck (average difference: 0.123 g/cm²; 95% confidence interval [CI] 0.105–0.141 g/cm²) than at the lumbar spine (average difference 0.019 g/cm²; 95% CI, 0.005–0.036 g/cm²). Results of LASSO regression indicated that lean mass was the only predictor of BMD for either men or women. Each kilogram increase in lean mass was associated with ∼0.01 g/cm² increase in BMD. Lean mass alone explained 16% and 36% of variation in lumbar spine and femoral neck BMD, respectively.

Conclusions

Lean mass, not fat mass, is the main determinant of peak bone mineral density. This finding implies that good physical activity during adulthood can contribute to the maximization of peak bone mass during adulthood.

Bone mineral density of proximal femur in adult Chinese females

OBJECTIVE

This study was designed to establish bone mineral density (BMD) reference data of proximal femur, research the effect of age, height and weight on BMD of proximal femur, and estimate the prevalence of osteoporosis in a Chinese female population. In addition we compared the results with Lebanese and USA white women reference data.

METHODS

Our study was conducted at one center, including 1578 Chinese women, aged 20-79years. We measured the BMD for proximal femur using dual-energy X-ray absorptiometry, and then established a reference database of proximal femur and set up regression equations of age, height and weight for BMD at proximal femur to research the effects of age, height and weight on BMD. After that, we calculated the standardized BMD and compared them with Lebanese and USA white women reference data.

RESULTS

The peak BMD occurred in the age range 30-39 years for femoral neck and Ward's triangle, and 40-49 years for trochanter in Chinese women, which were later than in Lebanese and USA white women. The BMD of proximal femur in Chinese women were lower than Lebanese and USA white women in most age ranges. Weight profoundly influenced BMD in all age groups, and age and height mainly effected BMD in older age groups. The standardized prevalence of osteoporosis among Chinese women of 50-79 years old was 9.6% in femoral neck, which was higher than Lebanese but lower than USA white women.

CONCLUSION

The BMD database of proximal femur in Chinese women we established is normative and different from Lebanese and USA white women reference data, which provides more reliable information on the prevalence of osteoporosis in China.

Analysing body composition as compositional data: An exploration of the relationship between body composition, body mass and bone strength

Human body composition is made up of mutually exclusive and exhaustive parts (e.g. %truncal fat, %non-truncal fat and %fat-free mass) which are constrained to sum to the same total (100%). In statistical analyses, individual parts of body composition (e.g. %truncal fat or %fat-free mass) have traditionally been used as proxies for body composition, and have been linked with a range of health outcomes. But analysis of individual parts omits information about the other parts, which are intrinsically co-dependent because of the constant sum constraint of 100%. Further, body mass may be associated with health outcomes. We describe a statistical approach for body composition based on compositional data analysis. The body composition data are expressed as logratios to allow relative information about all the compositional parts to be explored simultaneously in relation to health outcomes. We describe a recent extension to the logratio approach to compositional data analysis which allows absolute information about the total of the compositional parts (body mass) to be considered alongside relative information about body composition. The statistical approach is illustrated by an example that explores the relationships between adults' body composition, body mass and bone strength.

The Association between High Body Mass Index and Early Clinical Outcomes in Patients with Proximal Femur Fractures

Background: Fractures of the proximal femur constitute daily work in orthopedic trauma surgery. With the continuous increase of obesity in the general population, surgeons face several known technical challenges. The aim of this study was to investigate the association of high body mass index (BMI) in patients with proximal femur fractures with intra- and postoperative adverse events, as well as with functional outcomes after successful surgery. Methods: In this retrospective, single-center cohort study, 950 patients who sustained a fracture of the proximal femur (femoral neck fracture or trochanteric fracture) and underwent surgical treatment at our level I trauma center between 2003 and 2015 were included. Patient-specific data were obtained in regard to demographics, comorbidities, and fracture morphology. In-hospital postoperative complications (i.e., need for revision surgery, wound site infection, pneumonia, urinary tract infection, necessary transfusion, and deep-vein thrombosis) were analyzed, along with the length of hospitalization and overall mortality rate. Functional outcome was assessed using the Barthel index and the patient’s ability to walk on crutches. Mortality rate and need for revision surgery were assessed over a two-year time period. Any adverse event was correlated to one of the four WHO’s BMI groups. Results: The cohort included 80 (8.4%) underweight patients, 570 (60.0%) normal weight patients, 241 (25.4%) overweight patients, and 59 (6.2%) obese patients. We found more femoral neck fractures (506, or 53%) than trochanteric fractures (444, or 47%). In bivariate analysis, no significant difference was found in regard to overall mortality or postoperative complications. Hospitalization time (LOS) differed between the underweight (12.3 ± 4.8 days), normal (13.6 ± 7.8 days), overweight (14.2 ± 11.7 days), and obese patients (16.0 ± 9.7 days) (p = 0.040). Operation time increased stepwise with increasing BMI: underweight = 85.3 ± 42.9 min; normal weight = 90.2 ± 38.2 min; overweight = 99.9 ± 39.9 min; obese = 117.2 ± 61.5 min (p < 0.001). No significant difference was found by analyzing functional outcomes. However, patients with intermediate BMI levels (18.5–30 kg/m²) tended to achieve the best results, as represented by a higher Barthel index score and the patient’s ability to walk on crutches. Conclusion: Increased BMI in patients with proximal femur fractures is associated with both longer operation time and length of hospitalization (LOS). Postoperative mobilization and functional outcomes appear to follow a reversed J-curve distribution (with overweight patients showing the best functional results), whereas both obese and underweight patients have associated poorer function.

Bone Mineral Density of Femur and Lumbar and the Relation between Fat Mass and Lean Mass of Adolescents: Based on Korea National Health and Nutrition Examination Survey (KNHNES) from 2008 to 2011

It is most important to reach the maximum bone density in the childhood period to prevent developing osteoporosis; it is widely known that increased body weight has a positive correlation with bone density and that even though both the fat mass and lean mass have a significant impact on bone density, the latter mass has more importance for adults. Therefore, the study analyzed to identify the relationship between bone density and both fat mass and lean mass of Korean adolescents. Subjects were chosen among 21,303 people from the Korea National Health and Nutrition Examination Survey (KNHNES) between 2008 and 2011 that took a bone density checkup; as a result, 1454 teenagers aged between 12 and 18 were selected. Data analysis was performed in SAS ver. 9.4 (SAS Institute Inc., Cary, NC, USA) following the KNHNES and the weighted complex sample analysis was conducted; body fat mass and lean mass were divided into quintile groups, and to figure out the differences in bone density that were analyzed in six models adjusted by body weight (kg) and walking (yes/no), muscle strengthening exercises (yes/no), nutrition (intake of ca (g), and serum vitamin D (ng/mL)). Then, the generalized linear model (GLM) and trend test were conducted for each gender with a significance level of 0.05. The bone density differences of fat mass and lean mass were analyzed. The result of Model 6 considering all correction variables is as follows; in the case of male adolescents, the total femur and lumbar spine showed a significant difference (F = 13.120, p < 0.001; F = 12.900, p < 0.001) for fat mass, and the trend test showed that the figures significantly decreased (β = −0.030, p < 0.001; −0.035, p < 0.001). Meanwhile, for lean mass, the total femur and lumbar spine had a significant difference (F = 16.740, p < 0.001; F = 20.590, p < 0.001) too, but the trend test showed a significant increase (β = 0.054, p < 0.001; 0.057, p < 0.001). In the case of female adolescents, the lumbar spine (F = 3.600, p < 0.05) for lean mass showed a significant difference, and it also significantly rose in the trend test too (β = 0.020, p < 0.01). To sum up the results, for male adolescents, the bone density differences for fat mass (FM) and lean mass (LM) all had significant differences, but for female adolescents, only the lumbar spine for LM showed such a result. Meanwhile, both genders showed that LM had a more positive impact on bone density than FM.

Anti-fracture Efficacy of Monthly Risedronate Compared with That of Weekly Risedronate in Postmenopausal Korean Women with Osteoporosis: A Nationwide Cohort Study

Background

Intermittent dosing regimens for oral risedronate (once-monthly and once-weekly) were developed for patient convenience. While several studies have reported the anti-fracture efficacy of weekly dosing, few have assessed monthly dosing. The lower efficacy of monthly dosing has been previously suggested. The aim of this study was to compare the anti-fracture efficacy of monthly and weekly dosing.

Methods

We obtained information from the Korea National Health Insurance Service database from 2012 to 2017 of Korean women of ≥50 years of age who used weekly or monthly risedronate. We compared the time of occurrence of the first osteoporotic fracture after the first prescription of risedronate. Using a Cox proportional model, we assessed incidence rate ratios (IRRs) with 95% confidence intervals (CIs) for fractures at any site, and the hip, vertebral, and non-vertebral sites between both regimens. Propensity score weighting was used to balance the treatment groups.

Results

The study populations were distributed according to dosing frequency (monthly, 27,329; weekly, 47,652). There was no significant difference in the incidence rate of new fractures in any site (IRR, 1.008; 95% CI,0.963–1.055; P=0.737), hip (IRR, 0.999; 95% CI, 0.769–1.298; P=0.996), vertebral (IRR, 0.962; 95% CI, 0.890–1.040; P=0.330), or non-vertebral (1.022; 95% CI, 0.968–1.078; P=0.439) sites between monthly and weekly risedronate.

Conclusion

The anti-fracture efficacy at any site and the examined individual sites was similar for the monthly and weekly risedronate regimens. Large-scale randomized controlled trials are required for confirmation.

Determinants of Bone Health Status in a Multi-Ethnic Population in Klang Valley, Malaysia

Background and objectives: Studies on osteoporosis risk factors are limited in Malaysia, so this study assesses the factors associated with bone health assessed using dual-energy X-ray absorptiometry (DXA) among Malaysians aged ≥40 years. Subjects and Methods: Data on demography, medical history, dietary and lifestyle practices of 786 Malaysians (51.4% women) aged ≥40 years recruited in Klang Valley were obtained. Their body composition and bone health were determined using DXA. The association between risk factors and bone health status was assessed using binary logistic regression. Results: The prevalence of suboptimal bone health and osteoporosis was higher in women (59.4% and 16.1%) than men (40.8% and 8.4%). Overall, the predictors of suboptimal bone health and osteoporosis among the subjects were increased age and higher fat mass. Lower monthly income was positively associated with osteoporosis. Being menopausal was a risk factor for both suboptimal bone health and osteoporosis in women. Women with no formal education were more likely to get osteoporosis. Being a smoker and Chinese were positively related to suboptimal bone health among men. Meanwhile, predictors of osteoporosis among men were regular alcohol and dairy product consumption, higher fat mass and having a tertiary education. Conclusions: This study calls for immediate and effective interventions for middle-aged and elderly populations with risk factors to halt the progression of bone loss.

Bone Health and its Relation to Energy Intake, Fat Mass and its Distribution

BACKGROUND AND OBJECTIVES

Osteoporosis and obesity are two of the most important inter-related diseases worldwide. This study aimed to investigate impact of fat mass and its distribution on bone health in relation to energy intake among sample of Egyptian women.

MATERIALS AND METHODS

A cross-sectional study included 116 Egyptian women with age range 25-65 years old. They were classified according to the menopause into 2 groups: Pre-menopausal (n = 51) and post menopausal (n = 65). All participants have undergone anthropometric measurements, body composition, DEXA and laboratory investigations.

RESULTS

Among overweight/obese women, pre-menopausal women had significant higher values of BMR and BMD at both lumbar spines, neck of femur and significant lower values of central obesity (waist/hip ratio, waist/height ratio, visceral fat) and C-terminal peptides than postmenopausal ones. Among pre and post-menopausal women, BMD at both sites had significant positive correlations with obesity markers (BMI, waist and hip circumferences), fat mass, BMR, in addition to fat distribution, visceral fat, leptin among pre-menopausal women and C-terminal peptide among postmenopausal women. Among pre-menopausal women, BMR significantly explained 56% of the variations in BMD at neck of femur, while at lumbar spines the best model was BMI, BMR and waist circumference, which significantly explain 33% of the variations in BMD.

CONCLUSION

Bone health positively correlated with BMI, fat mass and its distribution and BMR, particularly at femur neck, among pre and post-menopausal Egyptian women. Overweight/obesity can be considered as a protective factor for bone health.

Associations between body mass index, body composition and bone density in young adults: findings from a southern Brazilian cohort

BACKGROUND

This study aimed to evaluate the association of body composition components and obesity with bone density.

METHODS

Prospective study with data on 2968 members of the 1993 Pelotas Birth Cohort from follow-ups at 18 and 22 years of age. Areal bone mineral density (aBMD, g/cm²) was evaluated for whole body, lumbar spine, and femoral neck at 22 years using dual-energy X-ray absorptiometry. Simple and multiple linear regression, stratified by sex, were used to assess the effect of BMI, fat mass (FMI) and lean mass index (LMI), evaluated at 18 and 22 years, and obesity trajectories classified by FMI and categorized as "never", "only at 18 years", "only at 22 years" or "always" on aBMD.

RESULTS

Among men, the largest coefficients were observed for BMI, followed by lean mass and fat mass. Compared to fat mass, lean mass presented the largest coefficients for all sites, with the strongest associations observed for the femoral neck (β: 0.035 g/cm²; 95% CI: 0.031; 0.039 for both follow-ups), while the largest effect for FMI was observed for whole-body aBMD at 18 years (β: 0.019 g/cm²; 95% CI: 0.014; 0.024). Among women, the strongest associations were observed for LMI. The largest coefficients for LMI and FMI were observed for femoral neck at age 18, presented β: 0.030 g/cm², 95% CI: 0.026, 0.034 for LMI and β: 0.012 g/cm²; 95% CI: 0.009; 0.015) for FMI. Men who were "always obese" according to FMI had smallest aBMD for spine (β: -0.014; 95%CI: - 0.029; - 0.001). Women who were obese "only at 18 years" had smallest aBMD for the whole-body (β: -0.013; 95%CI: - 0.023; - 0.002), whereas those who were obese "only at 22 years" had larger whole-body and femoral neck aBMD (β: 0.013; 95%CI: 0.009; 0.017 and β: 0.027; 95%CI: 0.016; 0.038, respectively) and those "always obese" for whole-body aBMD (β: 0.005; 95%CI: 0.001; 0.011) compared to the reference category.

CONCLUSIONS

The indexes were positively associated with aBMD in this sample. Fat mass had smaller positive influence on these outcomes than lean mass, suggesting the most important body composition component for bone density is the lean mass.