Associations of Fat Mass and Fat Distribution With Bone Mineral Density in Non-Obese Postmenopausal Chinese Women Over 60 Years Old

Association between lean body mass to visceral fat mass ratio and bone mineral density in United States population: a cross-sectional study

BACKGROUND

Studies have explored the correlation between body composition and bone mineral density (BMD), but there has yet to be a consensus. Thus, the present study aims to comprehensively investigate the association between lean body mass, adipose tissue, and BMD.

METHODS

We conducted a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) (2011-2018) with 11,227 subjects. Multiple linear regression, smoothed curve fitting, threshold, and saturation effect analysis were used to explore the association between lean body mass, visceral fat mass, and BMD. Also, we used the lean body mass to visceral fat mass ratio (Log LM/VFM) as a proxy variable to analyze its association with BMD alone.

RESULTS

After adjusting for potential confounding factors, the results showed a positive correlation between lean mass and total BMD (for continuous: β = 0.078, P < 0.001; for quartile: β = 0.138, P < 0.001), while visceral fat mass was negatively correlated (for continuous: β = -0.027, P < 0.001; for quartile: β = -0.065, P < 0.001). A positive correlation was observed when the alternative variable Log LM/VFM was analyzed separately for its association with BMD (for continuous: β = 0.034, P < 0.001; for quartile: β = 0.084, P < 0.001). In addition, subgroup analyses for gender, age, body mass index, hypertension, and diabetes showed that all subgroups except the diabetes subgroup showed a substantial degree of robustness (P < 0.05). The smoothed curve fitting showed a nonlinear relationship between Log LM/VFM and BMD, and there was a threshold effect with a critical value of 2.60.

CONCLUSION

Maintaining a proper ratio of lean body mass and visceral fat mass is beneficial for increasing BMD.

Causal relationship between body mass index, type 2 diabetes and bone mineral density: Mendelian randomization

OBJECTIVE

To reveal the relationship between Body Mass Index(BMI), type 2 diabetes, and bone mineral density(BMD) using a mendelian randomization (MR) approach.

METHODS

GWAS data on BMI, type 2 diabetes, and BMD were selected from the IEU GWAS database at the University of Bristol.Univariable, multivariable, and mediated MR analyses were used to explore the relationship between BMI, type 2 diabetes, and BMD. beta(β) values were given, and three methods, including inverse variance weighting, MR-Egger regression, and weighted median, were used in this analysis.

RESULTS

Univariable mendelian randomization (UVMR) results showed that BMI and type 2 diabetes were positively associated with BMD. However, the association between BMI and BMD was insignificant in the multivariable Mendelian randomization (MVMR) analysis, while that between type 2 diabetes and BMD remained significant. Mediated MR analysis indicated that type 2 diabetes mediated the regulation of BMD by BMI.

CONCLUSION

This study provides evidence supporting a positive causal association between BMI, type 2 diabetes, and BMD. Type 2 diabetes acts as a mediator in the regulation of BMD by BMI, indicating that both BMI and type 2 diabetes exert a protective influence on BMD.

Association between Adiposity and Bone Mineral Density in Adults: Insights from a National Survey Analysis

Adiposity and bone mineral density (BMD) are closely associated. The aim of this research was to investigate the association between BMD and adiposity measures in adults, including gynoid percent fat (GPF), android percent fat (APF), total percent fat (TPF), visceral adipose tissue percent (VAT%), and total lean mass percent (TLM%). Participants (n = 11,615) aged 18 years and older were analyzed using data from the National Health and Nutrition Examination Survey (NHANES) spanning from 1999 to 2018. Associations between BMD and adiposity measures were investigated, and potential differences based on gender and age were explored. Significant negative associations were observed among TPF, APF, GPF, VAT%, and BMD in the fully adjusted models, while TLM% and BMD were positively associated. Stratifying by age and sex, TPF, GPF, and VAT% consistently demonstrated a negative correlation with BMD. In the young adult group, a TPF of 38.2% eliminated the negative correlation between BMD and TPF. Male BMD exhibited an inverted U-shaped relationship with APF, peaking at 35.6%, while a similar pattern was observed for the middle-aged group BMD and APF, with a peak at 31.7%. This large-sample research found a significant negative association between adiposity measures and BMD, providing valuable revelations regarding the intricate connection between adiposity and bone health.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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