Soft tissue composition and the risk of low bone mineral density: the Fourth Korea National Health And Nutrition Examination Survey (KNHANES IV-3), 2009

Adipopenia is associated with osteoporosis in community-dwelling non-underweight adults independent of sarcopenia

The effect of fat deficit on bone metabolism is understudied. This study showed that low body fat percent (adipopenia) in non-underweight community adults was associated with elevated odds of osteoporosis independent of low lean mass, highlighting potential clinical importance of adipopenia as an osteoporosis risk factor particularly in older adults.

PURPOSE

Although underweight is risk factor for osteoporosis, the association of low body fat percent (adipopenia) with osteoporosis in non-underweight adults remains unclear.

METHODS

Among individuals aged ≥ 50 years with body mass index ≥ 18.5 kg/m² in the Korean National Health and Nutrition Examination Survey 2008-2011, appendicular lean mass (ALM) and body fat percent (BFP) were measured using dual-energy x-ray absorptiometry. Low lean mass was defined as ALM/height² < 7.0 kg/m² and < 5.4 kg/m² in men and women, respectively. Osteoporosis was defined as a bone mineral density (BMD) T-score ≤ -2.5 at the lumbar spine, femoral neck, or total hip. Participants were grouped into adipopenia (BFP < 17% in men; < 30%, in women; 1 standard deviation below the mean), normal, and obesity (BFP > 30% in men; > 40% in women) groups.

RESULTS

Of the 5,830 participants (women 50.2%, mean age 63.9 years), 793 had adipopenia. The adipopenia group had a higher prevalence of osteoporosis (31%) than the normal (21%) or obesity groups (27%; p < 0.001). The presence of adipopenia was associated with 61% elevated odds of prevalent osteoporosis (p < 0.001) independent of low lean mass and covariates, which remained robust using different thresholds for adipopenia. Individuals with adipopenia and low lean mass had 3.5-fold elevated odds of osteoporosis compared to those with normal lean mass and fat percent. The association between adipopenia and osteoporosis was stronger in older women compared to middle-aged women (OR 1.93 vs. 0.99, P for interaction = 0.023).

CONCLUSION

Adipopenia was associated with osteoporosis in non-underweight adults, independent of low lean mass and covariates.

Body composition and bone mineral density in postmenopausal women with rheumatoid arthritis

Aim – to study the relationship between body composition and bone mineral density (BMD) in postmenopausal women with rheumatoid arthritis (RA).

Material and methods. 68 postmenopausal women, median age 59 [54; 63] years, with RA were included in the study. Bone mineral density (BMD) and body composition were assessed with dual energy X-ray absorptiometry.

Results. 33 (48.5%) women had osteopenia, and 17 (25.0%) – osteoporosis (OP). Low lean muscle mass was found in 10 (14.7%) patients. There were positive correlations between different areal BMD and body weight, trunk fat, trunk lean muscle mass and total lean muscle mass. In the multivariate linear regression analysis total lean muscle mass was associated with BMD of lumbar spine (β=0.638; p=0.001) and total hip (β=0.473; p=0.008), and appendicular lean muscle mass, estimated using the appendicular muscle index, with femoral neck BMD (β=0.360; p=0.014).

Conclusion. 73.5% of patients with RA had a reduced BMD, and 14.7% women – low muscle mass. The revealed significant association between the lean muscle mass and BMD of lumbar spine and proximal femur indicates the importance of detecting and correcting low lean muscle mass, as well as preventing its decline in order to prevent loss of BMD and osteoporotic fractures.

Bone mineral density in young adults: the influence of vitamin D status, biochemical indicators, physical activity and body composition

The aim of the study was to assess the associations of bone mineral density and bone mass with physical activity levels, vitamin D, phosphorus, magnesium, total cholesterol and triglyceride concentration and body composition in young women and men. Physical activity has the most significant effect on bone status especially in men.

PURPOSE

The aim of the study was to assess the associations of bone mineral density and bone mass with physical activity levels, vitamin D, phosphorus, magnesium, total cholesterol and triglyceride concentration and body composition in young women and men.

METHODS

One hundred subjects aged 19-24 years were included. Bone mineral density (BMD) in distal and proximal parts was evaluated by forearm densitometry. Body composition was analysed with the use of JAWON-Medical-x-scan. The following biochemical indicators were analysed: 25(OH) D and 1,25(OH)2D, magnesium, phosphorus, total cholesterol and triglycerides. Physical activity levels were assessed by interview.

RESULTS

Significant correlations between BMD and physical activity, skeletal muscle mass and body fat percentage were revealed in men. Among women, considerably weaker correlations of BMD with body composition and physical activity were noted than in men. BMD in the distal part correlated only with lean body mass, soft lean mass and body fat percentage. The strongest relationship between physical activity and bone mineral status parameters was noted for BMD in men. In women, physical activity did not affect BMD.

CONCLUSIONS

Physical activity has the most significant effect on bone status especially in men.

Body composition as a frailty marker for the elderly community

Background

Body composition (BC) in the elderly has been associated with diseases and mortality; however, there is a shortage of data on frailty in the elderly.

Objective

To investigate the association between BC and frailty, and identify BC profiles in nonfrail, prefrail, and frail elderly people.

Methods

A cross-sectional study comprising 235 elderly (142 females and 93 males) aged ≥65 years, from the city of Amparo, State of São Paulo, Brazil, was undertaken. Sociodemographic and cognitive features, comorbidities, medication, frailty, body mass index (BMI), muscle mass, fat mass, bone mass, and fat percent (%) data were evaluated. Aiming to examine the relationship between BC and frailty, the Mann–Whitney and Kruskal–Wallis nonparametric tests were applied. The statistical significance level was P<0.05.

Results

The nonfrail elderly showed greater muscle mass and greater bone mass compared with the prefrail and frail ones. The frail elderly had greater fat % than the nonfrail elderly. There was a positive association between grip strength and muscle mass with bone mass (P<0.001), and a negative association between grip strength and fat % (P<0.001). Gait speed was positively associated with fat mass (P=0.038) and fat % (P=0.002). The physical activity level was negatively associated with fat % (P=0.022). The weight loss criterion was positively related to muscle mass (P<0.001), bone mass (P=0.009), fat mass (P=0.018), and BMI (P=0.003). There was a negative association between fatigue and bone mass (P=0.008).

Discussion: Frailty in the elderly was characterized by a BC profile/phenotype with lower muscle mass and lower bone mass and with a higher fat %. The BMI was not effective in evaluating the relationship between BC and frailty. The importance of evaluating the fat % was verified when considering the tissue distribution in the elderly BC.

Is FEV(1) an indicator of low bone mineral density in adults? The Fifth Korea National Health and Nutrition Examination Survey

The association between forced expiratory volume in 1 s (FEV1) and bone mineral density (BMD) is heterogeneous in population-based studies. This study aimed to investigate this relationship when sex and menopausal status in women, BMD sites, and anthropometric measures were taken into account. In 3,975 Koreans (1,783 men, 662 premenopausal women, 1,530 postmenopausal women, aged 40-91 years) participating in the Fifth Korea National Health and Nutrition Examination Survey in 2010-2011, this relationship for BMD at femur (total and neck) and lumbar spine was examined in each subgroup after adjusting for age, smoking, and alcohol habit, physical activity, calcium intake, osteoporosis treatment, and anthropometry (weight and height, height and BMI, or height, lean mass, and fat mass). Airflow limitation (FEV(1) ≥ 80, 50-80, and < 50% of predicted FEV(1)) and lower vs. higher BMD using BMD values at site and subgroup-specific 10 percentile of BMD distribution were defined. In multiple regression analysis, the association between FEV(1) and BMD was significant in premenopausal women [B = 0.027-0.031 (total femur), 0.035-0.037 (femoral neck), p < 0.05] but not in other subgroups. In logistic regression analysis, severe airflow limitation was associated with lower BMD in postmenopausal women [OR 2.21-2.37 (total femur), 2.25 (femoral neck), p < 0.05] and premenopausal women (OR 2.14, 95% CI, 1.01-4.50 for femoral neck in height and body composition-adjusted model), but not exhibit these associations in men. As a whole, the associations with spine BMD were non-significant. Therefore, the associations were sex-, menopausal status in women-, and BMD site-specific, while the types of anthropometry had similar effects on the associations.

Gender Difference in Association Between Appendicular Skeletal Muscle Mass and Cardiometabolic Abnormalities in Normal-Weight and Obese Adults

The objective of this study was to investigate whether the relationships of appendicular muscle mass (ASM) with insulin resistance (IR) and metabolic syndrome (MS) vary by gender or obesity. Data of 10 146 normal-weight and obese men and women aged 19 to 93 years from the Korea National Health and Nutrition Examination Survey in 2009 and 2010 were analyzed. In normal-weight men and women, unadjusted odds ratio (OR) of being MS and IR significantly increased with lower ASM/wt. After adjusting for lifestyle factors, these ORs were still significant in normal-weight men but not in women. After controlling for other covariates, lower ASM/wt was related to higher risk for IR but not to MS in obese men. In obese women, relationship of lower ASM/wt with higher risk for MS disappeared after adjusting for covariates. Association between skeletal muscle mass and cardiometabolic abnormalities is dependent on gender and obesity in Korean adults.