Determinants of Bone Mass and Insulin Resistance in Korean Postmenopausal Women: Muscle Area, Strength, or Composition?

Pharmacologic therapeutics in sarcopenia with chronic kidney disease

Inflammation, metabolic acidosis, renin-angiotensin system activation, insulin resistance, and impaired perfusion to skeletal muscles, among others, are possible causes of uremic sarcopenia. These conditions induce the activation of the nuclear factor-kappa B and mitogen-activated protein kinase pathways, adenosine triphosphate ubiquitin-proteasome system, and reactive oxygen species system, resulting in protein catabolism. Strategies for the prevention and treatment of sarcopenia in chronic kidney disease (CKD) are aerobic and resistance exercises along with nutritional interventions. Anabolic hormones have shown beneficial effects. Megestrol acetate increased weight, protein catabolic rate, and albumin concentration, and it increased intracellular water component and muscle mass. Vitamin D supplementation showed improvement in physical function, muscle strength, and muscle mass. Correction of metabolic acidosis showed an increase in protein intake, serum albumin levels, body weight, and mid-arm circumference. The kidney- gut-muscle axis indicates that dysbiosis and changes in gut-derived uremic toxins and short-chain fatty acids affect muscle mass, composition, strength, and functional capacity. Biotic supplements, AST-120 administration, hemodiafiltration, and preservation of residual renal function are alleged to reduce uremic toxins, including indoxyl sulfate (IS) and p-cresyl sulfate (PCS). Synbiotics reversed the microbiota change in CKD patients and decreased uremic toxins. AST-120 administration changed the overall gut microbiota composition in CKD. AST-120 prevented IS and PCS tissue accumulation, ameliorated muscle atrophy, improved exercise capacity and mitochondrial biogenesis, restored epithelial tight junction proteins, and reduced plasma endotoxin levels and markers of oxidative stress and inflammation. In a human study, the addition of AST-120 to standard treatment had modest beneficial effects on gait speed change and quality of life.

Medications and medical expenditures for diabetic patients with osteoporosis in Beijing, China: A retrospective study

AIMS

This study aimed to clarify the changes in treatment regimens and medical expenditures in diabetic patients with osteoporosis.

METHODS

We recruited 2,853,036 diabetic patients from the Beijing medical insurance database between 2016 and 2018. Among them, 406,221 patients also had osteoporosis. Clinical characteristics, treatment regimens, and medical costs were investigated in diabetic patients with and without osteoporosis.

RESULTS

Diabetes and osteoporosis were most prevalent in participants aged 45---84 years. Compared with diabetic patients without osteoporosis, those with osteoporosis were prone to developing comorbidities and diabetic complications. They often required multiple glucose-lowering drugs and had a higher rate of insulin use. Similarly, osteoporosis leads to an increased number of medications for non-hypoglycemia as well as higher healthcare costs. These medications and costs increased with the number of complications and comorbidities. Interestingly, from 2016 to 2018, although diabetic patients with osteoporosis took more drugs, medical costs were lower year by year.

CONCLUSIONS

Osteoporosis might contribute to a worse condition in diabetic patients, and this population often requires more medications with higher medical costs.

A Cross-Sectional Study on Gluteal Muscles in Patients with Ankylosing Spondylitis at Different Stages of Hip Involvement

Hip involvement in ankylosing spondylitis (AS) is associated with severe functional impairment, and early diagnosis can improve the disease prognosis. We investigated gluteal muscle cross-sectional area (CSA) and radiodensity at different stages of hip involvement and their associations with AS-related clinical and laboratory parameters. This cross-sectional study included 83 patients with AS and 83 age- and sex-matched controls. Patients with AS were divided into three groups according to the Bath Ankylosing Spondylitis Radiology Hip Index system. The CSA and radiodensity of the gluteus maximus, medius, and minimus muscles were measured using computed tomography images. Muscle parameters were compared, and their relationships with clinical and laboratory parameters were evaluated. For the gluteus maximus, patients with AS had a lower CSA than controls, regardless of the degree of hip involvement. For the gluteus medius and minimus, patients with moderate/advanced hip involvement had significantly lower CSA and radiodensity than those with mild to no hip involvement. The severity of hip involvement was negatively associated with muscle parameters. CSA of the gluteus maximus decreased in early-stage hip involvement without any changes in radiographs, while radiodensity decreased in the later stages. Muscle parameters on computed tomography may be a more sensitive indicator than radiographic findings.

Association between Relative Handgrip Strength and Insulin Resistance in Korean Elderly Men without Diabetes: Findings of the 2015 Korea National Health Nutrition Examination Survey

BACKGROUND

Evidence regarding the association between handgrip strength (HGS) and insulin resistance in a non-diabetic population is scarce. This study aimed to investigate the association between relative HGS and insulin resistance in older men without diabetes, using a representative sample of the Korean male population.

METHODS

The study population comprised 206 participants aged 65-80 years, selected from the 2015 Korea National Health and Nutrition Examination Survey. Insulin resistance was defined as the upper tertile of the homeostatic model assessment of insulin resistance (HOMA-IR). Odds ratios and 95% confidence intervals for insulin resistance were assessed using multiple logistic regression analyses after adjusting for confounding variables.

RESULTS

The prevalence of insulin resistance decreased with increasing relative HGS. The prevalence in the T1, T2, and T3 groups was 46.0%, 32.2%, and 26.4%, respectively. Compared with the individuals in the highest tertile of relative HGS, the odds ratio (95% confidence interval) for insulin resistance in individuals in the lowest quartile was 2.82 (1.10-7.21) after adjusting for age, smoking, alcohol consumption, aerobic exercise, resistance exercise, systolic blood pressure, total cholesterol, residential area, household income, and education level.

CONCLUSION

Lower relative HGS was inversely associated with an increased risk of insulin resistance in older Korean men without diabetes. In clinical practice, relative HGS, which is a simple and inexpensive tool, could be a useful measure for identifying older men with insulin resistance. Moreover, these findings suggest that muscle strengthening exercises should be considered to reduce insulin resistance and increase insulin sensitivity.

Altered features of body composition in older adults with type 2 diabetes and prediabetes compared with matched controls

BACKGROUND

Ageing is accompanied by muscle loss and fat gain, which may elevate the risk of type 2 diabetes (T2D). However, there is a paucity of data on the distribution of regional lean and fat tissue in older adults with T2D or prediabetes compared with healthy controls. The objective of this study was to compare regional body composition [by dual-energy x-ray absorptiometry (DXA)], muscle and subcutaneous adipose tissue (SAT) thicknesses (by ultrasound), and ultrasound-based muscle texture features in older adults with T2D or prediabetes compared with normoglycaemic controls.

METHODS

Eighteen adults > 60 years with T2D or prediabetes (T2D group) were individually matched to normoglycaemic participants [healthy matched (HM) group] for age (±5 years), sex, and body fat (±2.5%). In a single study visit, all participants received a whole-body DXA scan and ultrasound assessment of the abdomen and anterior thigh. At these two landmarks, we used ultrasound to measure muscle and SAT thickness, as well as texture features of the rectus femoris and rectus abdominis. We also conducted an exploratory subanalysis on a subset of participants (n = 14/18 in the T2D group and n = 10/18 in the HM group) who underwent additional assessments including strength testing of the knee extensors (using a Biodex dynamometer), and a fasting blood sample for the measurement of circulating markers of glucose metabolism [glucose, insulin, c-peptide, and the homoeostatic model assessment of insulin resistance (HOMA-IR)].

RESULTS

The T2D group was 72 ± 8 years old (mean ± SD), predominantly male (n = 15/18; 83%), and overweight (BMI: 27.8 ± 4.2 kg/m² , 33.2 ± 5.3% body fat). DXA-derived upper arm lean mass was 0.4 kg greater (P = 0.034), and leg fat mass was 1.4 kg lower (P = 0.048), in the T2D vs. HM group. Ultrasound-based texture features were distinct between the groups [rectus abdominis blob size: 0.07 ± 0.06 vs. 0.30 ± 0.43 cm² , P = 0.045; rectus femoris local binary pattern (LBP) entropy: 4.65 ± 0.05 vs. 4.59 ± 0.08 A.U., P = 0.007]. When all participants who underwent additional assessments were pooled (n = 24), we observed that certain ultrasound-based muscle texture features correlated significantly with muscle strength (rectus abdominis histogram skew vs. power during an isokinetic contraction at 60°/s: r = 0.601, P = 0.003) and insulin resistance (rectus femoris LBP entropy vs. HOMA-IR: r = 0.419, P = 0.042).

CONCLUSIONS

Our findings suggest a novel body composition phenotype specific to older adults with T2D or prediabetes. We are also the first to report that ultrasound-based texture features correspond with functional outcomes. Future larger scale studies are needed to uncover the mechanisms underpinning these regional body composition differences.

The relationship between insulin resistance, bone mineral density, and fracture risk in postmenopausal women

Background/Aim. Skeletal muscles and bones are essential tissues that, in addition to supporting the body, are the primary site of postprandial glucose intake, which is significantly associated with insulin resistance. The aim of this study was to determine the effect of insulin resistance on bone mineral density (BMD) and fracture risk and re-evaluate the relationship between muscle properties and BMD and insulin resistance in postmenopausal women in Serbia. Methods. Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) was calculated in postmenopausal women who were divided into two groups. The ?cut-off? value of insulin resistance for the group with ?Low HOMA-IR? was < 2, and for ?High HOMA-IR? > 2. Fat mass (FM), lean mass (LM), and BMD were measured on the hip and spine using a densitometer with dual-energy X-ray absorptiometry. Results. FM and LM had an evident impact on BMD. The decrease in LM and fat buildup was associated with a higher incidence of insulin resistance. A positive correlation was confirmed between HOMA-IR and BMD on the spine and hip, but there was no correlation between insulin resistance and fracture risk. Conclusion. LM and FM have significant effects on BMD. The association between LM, FM, BMD and the onset of insulin resistance in postmenopausal women is confirmed. However, women with higher insulin resistance levels and higher BMD do not have a lower fracture risk.

Handgrip strength is positively associated with bone mineral density in middle and aged adults: results from NHANES 2013-2014

Few studies have examined the association between handgrip strength and BMD in specific subgroups. Therefore, we examined the associations of handgrip strength with BMD aged ≥ 40 years and found that handgrip strength is associated with BMD which is independent of BMI, physical activity, and other potential confounders.

PURPOSE

Previous studies have revealed that handgrip strength is a measure of muscular fitness and is associated with fracture and bone mineral density (BMD) in adolescents and adults, with conflicting results. In addition, few studies have examined the association between handgrip strength in predefined subgroups such as sex, age, and physical activity in a whole population.

METHODS

We examined the associations of handgrip strength with BMD in 2720 adults (1359 men and 1361 women) aged ≥ 40 years (mean age, 58.6 ± 11.8 years) from the National Health and Nutrition Examination Survey (NHANES) 2013-2014. NHANES collects data via household interviews and direct standardized physical examinations conducted in specially equipped mobile examination centers. The date of final data collection was 2014 and the present data analysis was conducted in January to February 2020.

RESULTS

Handgrip strength was significantly associated with total femur (r = 0.482, P < 0.001) and femoral neck BMD (r = 0.427, P < 0.001) among all participants, respectively. After adjustment for age, sex, race, body mass index (BMI), physical activity, smoking, history of diabetes, history of hypertension, and history of high cholesterol, each unit (1 SD) of BMI-adjusted handgrip strength was positively associated with 0.026 g/cm² increase in total femur BMD (P < 0.001) and 0.027 g/cm² increase in femoral neck BMD (P < 0.001). There was a significant increasing trend in total femur and femoral BMD as handgrip strength increased from the lowest quartile to the highest quartile (P for trend < 0.001). For subgroup analysis, there were no significant interaction effects of handgrip strength with BMD between predefined subgroups (all P > 0.05).

CONCLUSIONS

High level of handgrip strength is associated with increased BMD. The association is independent of BMI, physical activity, and other potential confounders.

Evaluation of hemorheological parameters as biomarkers of calcium metabolism and insulin resistance in postmenopausal women

BACKGROUND

Calcium, vitamin D and insulin resistance are linked to osteoporosis and cardiovascular disease in menopause.

OBJECTIVE

Determine if hemorheological parameters related to blood viscosity in microcirculation are linked to calcium metabolism and insulin resistance in menopause.

METHODS

25-Hydroxyvitamin D (25(OH)D)), 1, 25-dihydroxyvitamin D3 (1, 25(OH)2D), parathyroid hormone, ionized calcium, glucose, insulin and hemoglobin A1c were measured in blood from 43 volunteers. Red blood cells (RBC) aggregation, RBC deformability and whole blood viscosity were also performed.

RESULTS

25(OH)D showed a positive correlation with RBC deformability 0.60 Pa. Subjects with 25(OH)D≤29.00 ng/mL had lower RBC deformability 0.60 Pa, and higher RBC aggregation and higher HOMA-IR. Ionized calcium showed a negative correlation with RBC aggregation. Subjects with ionized calcium ≤1.24 mmol/L showed higher RBC aggregation. There was a positive correlation between HOMA-IR and RBC aggregation and HOMA-IR showed a negative correlation with RBC deformability 0.30 Pa. Subjects with HOMA-IR <1.80 showed lower RBC aggregation and higher RBC deformability at 0.30 Pa, 0.60 Pa, 1.20 Pa, 3.0 Pa and 6.0 Pa.

CONCLUSION

Low 25(OH)D, low ionized calcium and high HOMA-IR are related to impaired hemorheology in menopause. RBC aggregation and deformability can be used as biomarkers of calcium metabolism and insulin resistance in menopause.

Predictors of Sarcopenia in an Obese Asian Population

Sarcopenia is associated with obesity and might also be responsible for other disorders. Here, we investigated the prevalence of sarcopenia and its predictors in obese subjects. Subjects who underwent a medical health checkup and living-related liver donors were recruited. Obesity was defined as body mass index (BMI) ≥25 kg/m². Muscle mass was assessed using computed tomography at the 3^rd lumbar vertebra. The lowest quartile of the lumbar skeletal muscle index (LSMI) was considered sarcopenia. Among 466 obese subjects, 53 (11.4%) had sarcopenia. Subjects with sarcopenia were significantly older (mean 66.6 vs. 53.3 years) and had a significantly higher prevalence of hypertension (62.3 vs. 46.0%) and diabetes (45.3 vs. 31.0%), higher fibrosis-4 (FIB-4) index (mean 1.57 vs. 1.16), and higher atherosclerotic cardiovascular disease (ASCVD) risk score (mean 22.86% vs. 11.15%), whereas they had a significantly lower prevalence of female gender (13.2% vs. 27.8%), lower BMI (mean 26.4 vs. 27.4 kg/m²), and lower LSMI (mean 43 vs. 56 cm²/m²) than subjects without sarcopenia (all P < 0.05). On multivariate analysis, higher BMI (odd ratio [OR] = 0.599, P = 0.001) was independently associated with a reduced risk of sarcopenia, whereas higher ASCVD risk scores (OR = 1.045, P < 0.001) were independently associated with an increased risk of sarcopenia. Sarcopenia is significantly associated with lower BMI and higher cardiovascular risk in an obese Asian population.

Relationship of Body Composition with the Strength and Functional Capacity of People over 70 Years

BACKGROUND

Aging is a multifactorial physiological phenomenon, in which a series of changes in the body composition occur, such as a decrease in muscle mass and bone mineral density and an increase in fat mass. This study aimed to determine the relationship of muscle mass, osteoporosis, and obesity with the strength and functional capacity of non-dependent people over 70 years of age.

METHODS

A cross-sectional study was designed, whose study population was all people aged over 70 years, living independently and attending academic and recreational programs. Muscle strength and functional capacity of the participants were assessed by isometric exercises of lower and upper limbs and by four tests taken from the Senior Fitness Test, respectively. Bone mineral density, total mass, fat mass, total lean mass, arms lean mass, legs lean mass, and appendicular lean mass (ALM) was calculated by dual energy X-ray absorptiometry. Differences in muscle strength and functional capacity, according to the sex, muscle mass, mineral bone density and fat mass, were measured by χ2 test, independent samples Student's t-test, analysis of covariance and a 2-factor analysis of covariance; Results: 143 subjects were included in the study group. Men and women with an adequate amount of ALM adjusted for body mass index (BMI) had a maximal dynamic biceps strength in a single repetition, a maximal isometric leg extension strength, a maximal dynamic leg extension strength in a single repetition, a maximum right hand grip strength and maximum hand grip strength (the highest). Significantly higher values were observed in the maximal isometric biceps' strength in men with osteoporosis. Obese men had less isometric strength in the biceps and took longer to perform the chair stand test; Conclusions: Men and women with an adequate amount of ALM adjusted for BMI obtained better results in tests of muscle strength and functional capacity. However, osteoporosis and obesity are not related to these parameters.

Physical performance and chronic kidney disease development in elderly adults: results from a nationwide cohort study

Sarcopenia, which is characterized by muscle mass and physical performance, is closely associated with morbidities and mortality, especially among the elderly. However, the effect of physical performance on chronic kidney disease (CKD) development is not yet fully elucidated. A total of 30,871 adults aged 66 years with preserved renal function who underwent health screening examinations were evaluated. Physical performance was assessed using a 3-m timed up and go (TUG) test and the one-leg stand (OLS) test. The primary outcome was the development of CKD, defined as at least two consecutive measurements of estimated glomerular filtration rate < 60 mL/min/1.73 m². The rates of mortality and incident CKD development were significantly elevated with increases in TUG test scores but not in OLS scores. In the Cox hazards model, the highest TUG test score tertile was associated with an increased risk for CKD development (hazard ratio, 1.23; 95% confidence interval, 1.10-1.38) compared with the lowest tertile. No significant relationship was observed between OLS score and incident CKD risk. Poor physical performance, assessed using the TUG test, was related to an increased risk of CKD development.