Dual-energy X-ray Absorptiometer Research Articles

Appendicular Skeletal Muscle Mass in Older Adults Can Be Estimated With a Simple Equation Using a Few Zero-Cost Variables.

Assessing appendicular skeletal muscle (ASM) mass is crucial for the diagnosis of numerous pathologies related to the decline of muscle mass in old age, such as sarcopenia, malnutrition, or cachexia. The dual-energy X-ray absorptiometer (DEXA) radiological technique, which is the gold standard for its assessment, is particularly costly and not routinely used in clinical practice. The aim of this study was to derive computationally simple equations capable of estimating the DEXA-measured ASM at zero cost in older adult populations. We used the cross-sectional data collected by the National Health and Nutrition Examination Survey (NHANES) over 7years (1999-2006). The study sample included 16,477 individuals aged 18years and over, of which 4401 were over 60years old. We considered 38 nonlaboratory variables. For the derivation of the equations, we employed the Brain Project, an innovative artificial intelligence tool that combines genetic programming and neural networks. The approach searches simultaneously for the mathematical expression and the variables to use in the equation. The derived equations are useful to estimate the DEXA-measured ASM. A simple equation that includes the body weight of the patient as the sole variable can estimate the outcome of DEXA with an accuracy equivalent to previously published equations. When used to identify individuals over 60years old with muscle mass loss, it achieved an area under the curve (AUC) value of 0.85 for both males and females. The inclusion of sex and anthropometric data (thigh and arm circumference) improved the accuracy for male individuals (AUC 0.89). The model is also suitable to be applied to the general adult population of 18years of age or older. Using more than 3 variables does not lead to better accuracy. The newly proposed equations have better diagnostic accuracy than previous equations for the estimation of DEXA-measured ASM. They are readily applicable in clinical practice for the screening of muscle mass loss in the over 60-year-old population with nearly zero-cost variables. The most complex model proposed in this study requires only the inspection of a simple diagnostic chart to estimate the status of muscle mass loss.

Bone Quality Indices Correlate with Growth Hormone Secretory Capacity in Women Affected by Weight Excess: A Cross-Sectional Study.

Background/Objectives: Obesity can be associated with impaired growth hormone (GH) secretion, with possible negative repercussions on bone health. We aimed to investigate the relationships between GH secretory capacity, evaluated with GHRH + arginine stimulation test, and bone parameters, assessed with a dual-energy X-ray absorptiometer, in a population of adult female patients affected by overweight and obesity. Methods: We assessed 276 women affected by overweight or obesity referred to the High-Specialization Center for the Care of Obesity, Umberto I Polyclinic, between 2014 and 2019 with signs or symptoms of growth hormone deficiency (GHD). Results: A total of 97 patients were diagnosed with GHD, and 179 patients with normal GH secretion were considered our control group. GHD patients showed a significantly reduced trabecular bone score (TBS) (p = 0.01). Bone quality parameters corrected for body mass index (BMI) had a positive and significant linear correlation with stimulated GH secretory capacity. Conclusions: In conclusion, bone quality, evaluated by TBS and hip structural analysis, correlates with GH-stimulated secretory capacity. GHD may act as an additive factor in the alteration of bone microarchitecture in patients affected by obesity, who are already at a higher risk of fractures.

Features of Bone Mineral Density, Calcium-Phosphorus Metabolism and Bone Remodeling in Patients with Systemic Lupus Erythematosus

Introduction. Systemic lupus erythematosus (SLE) is a complex autoimmune disease with variable clinical manifestations associated with multiple autoantibodies formation and deposition of immune complexes, and other immune processes. Despite significant advances in treatment, the disease remains disabling, in particular, due to increased bone fragility and low-energy fractures. The study of bone remodeling in patients with SLE should help to improve the therapy and quality of their treatment. The aim of the study. To investigate the features of bone mineral density, calcium-phosphorus metabolism and bone remodeling in patients with systemic lupus erythematosus. Materials and methods. The study involved 123 women with SLE aged 21-51 years. The comparison group (CG) consisted of 25 women without SLE in premenopausal status of the appropriate age. The control group included 25 practically healthy women. In order to study bone mineral density (BMD), dual-energy X-ray densitometry (DXA) of the lumbar spine was performed using a dual-energy X-ray absorptiometer. For the study of calcium-phosphorus metabolism (CPM), total calcium (Ca), ionized Ca, phosphorus (P) in blood and Ca, P, creatinine in daily urine, as well as parathyroid hormone (PTH) and 25-hydroxyvitamin D in serum were determined. Markers of bone remodeling (osteocalcin, procollagen type 1 amino-terminal propeptide (P1NP) and isomerized C-terminal telopeptide (β-crosslaps) in serum were measured. To achieve the stated goal, the first step included the determination of bone damage prevalence in patients with the diagnosed SLE; the second step was directed towards the characterization the particular bone condition in patients with SLE based on the results of BMD, CPM indices and markers of bone remodeling assessment. Results and discussion. According to the results of DXA of the lumbar spine, 88 (71.54 %) women of the SG and only 8 (32.00 %) women of the CG had a decrease in BMD (p < 0.001). According to the mean values, the studied CPM indices of the SG patients, CG and control group wemen exposed no significant differences. Similarly, no significant differences were detected in the mean values of urinary phosphorus and in between blood PTH values in SG, CG, and control. The level of 25-hydroxyvitamin D was significantly lower in SG (15.14 ± 0.80 ng/ml) than in CG (19.62 ± 0.46 ng/ml) and control (22.38 ± 1.34 ng/ml) p < 0.05. The mean value of osteocalcin in woman with SLE was significantly lower than in CG and control (11.81 ± 0.49 ng/ml versus 18.61 ± 0.75 ng/ml and 19.28 ± 1.88, p < 0.001). No significant difference were detected in between the mean values of P1NP in SG, CG and control. The mean values of β-cross laps were significantly higher in patients with SLE (0.51 ± 0.02 ng/ml) compared to GC (0.26 ± 0.02 ng/ml) and control (0.28 ± 0.02 ng/ml), p < 0.001. Conclusions. Bone mineral density, calcium-phosphorus metabolism and bone remodeling in patients with systemic lupus erythematosus have peculiarities as follows: a significant decrease in bone mass in 71.54 % of patients, namely 18, 70 % - grade I osteopenia, 21.14 % - grade II osteopenia, 14.63 % - grade III osteopenia; 17.07 % - osteoporosis, increased calcium excretion, vitamin D deficiency, decreased osteoblastic and enhansed osteoclastic functions.

Synthetic phantoms enable calibration between abattoir based dual energy X-ray absorptiometers used for prediction of lamb carcass composition

Dual energy x-ray absorptiometry (DXA) devices were installed at two Australian abattoirs to predict computed tomography (CT) determined fat % and lean % of lamb carcasses. This study tested three algorithms developed for these devices, termed β1, β2 and β3, and assessed their accuracy and precision in predicting CT composition. Algorithm β3 included the use of a plastic phantom calibration block scanned by both DXA devices to adjust prediction equations, resulting in superior accuracy to the algorithms without phantom calibration (β1 and β2). When compared to the gold-standard CT composition, the bias of the DXA predictions was lowest when using algorithm β3 at the two sites (−1.17%, −0.49% for fat %, 0.11%, −0.37% for lean %). The difference of DXA composition predictions between sites was lowest when using algorithm β3, which demonstrated between site differences of 0.59 CT fat %, and 0.46 CT lean%. In contrast, algorithm β1 and β2 produced differences of 23.7% and 30.8% for CT fat, and 17.3% and 21.9% for CT lean between the two DXA devices. There was a small difference of 0.78% between the fat predictions of the first DXA image compared to the second DXA image for each carcass. The precision of predictions improved slightly using algorithm β3. This work demonstrates that the in-line DXA systems can produce comparable results across sites.

Dynamic correction of dual−energy x-ray absorptiometry images improves chain speed prediction of lamb composition in abattoirs

A prototype, on-line Dual Energy X-ray Absorptiometer (DXA) has shown high precision of the prediction of carcass composition for the purpose of improved sheep meat grading in the Australian lamb supply chain, albeit with small inaccuracies over time. These inaccuracies were present across hours, and more significantly across days, which were unacceptable for any accreditation of this device as an objective carcass measurement tool in Australia. This inaccuracy demanded the creation of a novel image−processing algorithm for the prototype DXA. This DXA was tested for repeatability of predictions of lamb carcass composition over minutes, hours, and days, using two developed image processing algorithms. There was high immediate repeatability for both algorithms when predicting lean muscle % in 40 lamb carcasses, with a maximum CV of 0.65% over five repeated scans. There was a decrease in the CV of the prediction of lean muscle % of 30 lambs scanned three times over a 48-h period from 5.93 to 1.19% when the superior algorithm was used. The inaccuracies of lean muscle % predictions were associated with increases in the unattenuated space pixel values in DXA images. Improvements of the current algorithm are required to demonstrate repeatability over time for the purpose of accreditation within the Australian sheep meat industry, and for possible expansion of this technology into international supply chains.

The effect of hyperlipidemia and body fat distribution on subclinical left ventricular function in obesity: a cardiovascular magnetic resonance study

BackgroundObesity is often associated with multiple comorbidities. However, whether obese subjects with hyperlipidemia in the absence of other complications have worse cardiac indices than metabolically healthy obese subjects is unclear. Therefore, we aimed to determine the effect of hyperlipidemia on subclinical left ventricular (LV) function in obesity and to evaluate the association of cardiac parameters with body fat distribution.Materials and methodsNinety-two adults were recruited and divided into 3 groups: obesity with hyperlipidemia (n = 24, 14 males), obesity without hyperlipidemia (n = 25, 13 males), and c ntrols (n = 43, 25 males). LV strain parameters (peak strain (PS), peak diastolic strain rate (PDSR), peak systolic strain rate) derived from cardiovascular magnetic resonance tissue tracking were measured and compared. Dual-energy X-ray absorptiometer was used to measure body fat distribution. Correlations of hyperlipidemia and body fat distribution with LV strain were assessed by multivariable linear regression.ResultsObese individuals with preserved LV ejection fraction showed lower global LV longitudinal, circumferential, and radial PS and longitudinal and circumferential PDSR than controls (all P < 0.05). Among obese patients, those with hyperlipidemia had lower longitudinal PS and PDSR and circumferential PDSR than those without hyperlipidemia (− 12.8 ± 2.9% vs. − 14.2 ± 2.7%, 0.8 ± 0.1 s−1 vs. 0.9 ± 0.3 s−1, 1.2 ± 0.2 s−1 vs. 1.4 ± 0.2 s−1; all P < 0.05). Multivariable linear regression demonstrated that hyperlipidemia was independently associated with circumferential PDSR (β = − 0.477, P < 0.05) in obesity after controlling for growth differences, other cardiovascular risk factors, and central fat distribution. In addition, android fat had an independently negative relationship with longitudinal and radial PS (β = − 0.486 and β = − 0.408, respectively; all P < 0.05); and visceral fat was negatively associated with longitudinal PDSR (β = − 0.563, P < 0.05). Differently, gynoid fat was positively correlated with circumferential PS and PDSR and radial PDSR (β = 0.490, β = 0.481, and β = 0.413, respectively; all P < 0.05).ConclusionHyperlipidemia is independently associated with subclinical LV diastolic dysfunction in obesity. Central fat distribution (android and visceral fat) has a negative association, while peripheral fat distribution (gynoid fat) has a positive association on subclinical LV function. These results suggest that appropriate management of hyperlipidemia may be beneficial for obese patients, and that the differentiation of fat distribution in different regions may facilitate the precise management of obese patients.Clinical trials registration Effect of lifestyle intervention on metabolism of obese patients based on smart phone software (ChiCTR1900026476).

Establishment of Obesity Diagnosis Criteria Using Body Volume Index of 3D BodyScanner

PURPOSE This study sought to establish obesity diagnosis criteria by using the Body Volume Index (BVI) by body part extracted through 3D BodyScanner.METHODS The body fat percentage was measured using Dual Energy X-ray Absorptiometer (DEXA) for 225 participants (male = 119, female = 106), and BVI for eight body parts was measured using 3D BodyScanner. Independent t-test and Receiver Operating Characteristic (ROC) analysis were conducted. ROC analysis calculated the Area Under the Curve (AUC), and the optimal cut-point by Youden's J index. Sensitivity, Specificity, Accuracy, Balanced Classification Rate (BCR), and F1-score (harmonic mean of recall and precision) values were calculated to verify the validity of the optimal cut-point.RESULTS A statistically significant difference was observed in BVI by body part according to whether obesity was present for both men and women, and the obese group higher than the normal group. The optimal cut-point for each body part to diagnose obesity was 7.96 for shoulder, 9.79 for chest, 7.15 for upper abdominal, 7.71 for lower abdominal, 14.89 for total abdominal, 9.79 for thigh, 5.70 for calf, and 74.96 for total body volume in men. In case of women, this was 6.04 for shoulder, 9.82 for chest, 4.96 for upper abdominal, 6.23 for lower abdominal, 11.63 for total abdominal, 8.88 for thigh, 4.05 for calf, and 58.15 for total body volume, and the accuracy was 0.6~0.9.CONCLUSIONS BVI is a useful indicator for diagnosing obesity. However, this can be applicable only to Asian adults since there may be differences depending on race or age.

THU416 Trabecular Bone Score, Bone Mineral Density, And Fractures In Patients Of Chronic Kidney Disease With And Without Diabetes Mellitus

Abstract Disclosure: V. Suryadevara: None. R. Kg: None. A. Prasad: None. V. Sunthoju: None. P. Ps: None. R. Govindarajalou: None. J. Sahoo: None. S. Kamalanathan: None. D. Naik: None. Background and objectives: Chronic kidney disease-mineral bone disease (CKD-MBD) is a common yet neglected long-term complication of CKD. The primary objective of this study was to compare the proportion of patients with low trabecular bone score (TBS) in the CKD patients with diabetes mellitus (CKD-DM) and the CKD patients without DM (CKD-NDM). The secondary objectives were to compare bone mineral density (BMD) and morphometric vertebral fractures (VF) between the two groups. Methods: Patients of CKD with an estimated glomerular filtration rate (eGFR) &amp;lt; 60 mL/min/1.73m2, and not initiated on maintenance hemodialysis were recruited in the study. They were classified into the CKD-DM or the CKD-NDM group based on the presence of DM. Both groups were matched for age and gender. A detailed history was taken, and a physical examination was done to rule out secondary causes of osteoporosis. Serum creatinine, electrolytes, 25 hydroxy vitamin [25 (OH)D], and intact parathyroid hormone (iPTH) were analysed. Areal BMD was assessed using Hologic Discovery Wi dual-energy X-ray absorptiometer. TBS was estimated from spine BMD images using TBS iNsight software v 3.1.1 (Medimaps, Geneva). A dorsolumbar spine radiograph was performed to look for morphometric VFs. Results: 306 participants with CKD (153- diabetic and 153 non-diabetic) were included. The baseline characteristics were comparable between the two groups except for a higher BMI [24.13 (21.9-27.5) vs 21.86 (19.7-24.4) kg/m2], higher waist circumference [92.5 (85-99) vs 85 (80-93) cm], higher eGFR [31 (15.5-42.5) vs 25 (13-34) ml/min/1.73m2], lower magnesium [2 (1.8-2.2) vs 2.1 (1.8-2.4) mg/dl], and lower 25(OH)D [28.82 (21.3-38.6) vs 36.11 (28.4-47.3) ng/ml] in the CKD-DM group. The proportion of patients with low bone turnover (iPTH levels &amp;lt; 80 pg/ml) was higher in the CKD-DM group (34.2% vs 27.1%). The proportion of patients with low TBS was similar between the two groups (39.86% vs 41.83%; p=0.727). The BMD at lumbar spine (LS) [0.977 (0.877-1.128) vs 0.945 (0.814-1.148) g/cm2; p=0.219] and distal forearm (FA) [0.689 (0.618-0.736) vs 0.661 (0.576-0.731) g/cm2; p = 0.053] were also comparable between the two groups. However, BMD at femur neck (FN) [0.707 (0.624-0.798) vs 0.665 (0.586-0.768) g/cm2; p=0.012] and total hip (TH) [0.862 (0.760-0.951) vs 0.811 (0.713-0.916) g/cm2; p=0.006] were higher in the CKD-DM group. The prevalence of morphometric VF was similar between the two groups (8.5% vs 5.2%; p=0.258). Conclusion: In this cohort of pre-dialysis stage 3-5 CKD patients, the prevalence of low TBS, BMD at LS and distal FA were similar between the CKD-DM and the CKD-NDM groups. The BMD at FN and TH was higher in CKD with DM compared to CKD without DM. Presentation: Thursday, June 15, 2023

Relationship Between Body Segment Mass and Running Performance in Well-Trained Endurance Runners.

This study examined the relationship between body segment mass and running performance in endurance runners. The total (muscle, fat, and bone masses), lean (muscle mass), and fat masses of the leg, arm, and trunk segments in 37 well-trained endurance runners were measured using dual-energy X-ray absorptiometer. The relative segment mass was calculated by normalizing the absolute mass to body mass. There were no significant correlations between absolute total, lean, and fat masses of all 3 segments and personal best 5000-m race time. No significant correlations were also observed between all 3 relative masses of the arm segment and personal best 5000-m race time. In contrast, medium positive correlations were observed between the relative total and lean masses of the leg segment and personal best 5000-m race time (r = .387 and .335, respectively, both P ≤ .031). Furthermore, large negative correlations were observed between the relative total and lean masses of the trunk segment and personal best 5000-m race time (r = -.500 and -.548, respectively, both P ≤ .002). These findings suggest that a mass distribution with smaller leg mass and greater trunk mass may be advantageous for achieving better running performance in endurance runners.

Menarche age exceed 17years and menopausal age smaller than 48years may affect prevalence of osteoporosis for Chinese women.

A cross-sectional, population-based study. The purpose of this study was to explore relationship between prevalence of osteoporosis and menarche age, menstrual cycle, menstrual period, menopausal age, and menopause years for women. From March to October 2016, the cluster sampling method was used to conduct an osteoporosis-related questionnaire survey on women aged 40-80 in two communities in Lanzhou City, Gansu, China, and bone mineral density(BMD)was carried out using the DTX-200 dual-energy X-ray absorptiometer produced by the US OSTEOMETER company. The relationship between prevalence of osteoporosis and menarche age, menstrual cycle, menstrual period, menopausal age, and menopause years were analyzed using logistic regression analysis. There were 2224 female participates enrolled in this study and average age was 61.60 ± 8.05years and total rate of prevalence was 32.73%; among them, different menarche age, menstrual cycle, menopausal years, and menopausal age have statistical differences with the prevalence of osteoporosis, but there is no statistical difference between different menstruation and the prevalence of osteoporosis. Single logistic regression analysis found that older menarche age, earlier menopausal age, and longer menopausal years were related factors for the prevalence of osteoporosis, while menarche age exceed 17years and menopausal age smaller than 48years are risk factors for osteoporosis for women in multivariate regression analysis. In China, ages at menarche and menopause are associated with prevalence of osteoporosis. Later, menarche and earlier menopause are associated with higher osteoporosis risk. Menarche and menopause history may help identify women with increased risk of developing osteoporosis.

Predictive ability of novel volumetric and geometric indices derived from dual-energy X-ray absorptiometric images of the proximal femur for hip fracture compared with conventional areal bone mineral density: the Japanese Population-based Osteoporosis (JPOS) Cohort Study.

To clarify whether volumetric and geometric indices derived from novel three-dimensional (3D) modeling of the hip using dual-energy X-ray absorptiometric (DXA) images improve hip fracture prediction relative to areal bone mineral density (aBMD). We examined 1331 women who had completed the baseline survey and at least one follow-up survey over 20 years (age 40-79 years at baseline). Each survey included aBMD measurement at the hip by DXA. Volumetric and geometric indices of the hip at baseline and the 10-year follow-up were estimated from DXA images using a 3D modeling algorithm. Incident hip fractures during the 20-year follow-up period were identified through self-report. Cox proportional hazards regression models allowing for repeated measurements of predictors and outcomes were constructed, and their predictive ability for hip fracture was evaluated using areas under receiver operating characteristic curves (AUCs) and net reclassification improvement (NRI) over aBMD at the femoral neck (FN) and total hip (TH) as references. During a median follow-up of 19.8 years, 68 incident hip fractures were identified (2.22/1000 person-years). A significantly larger AUC of trabecular volumetric BMD (vBMD) at the total hip (AUC = 0.741), femoral neck (AUC = 0.748), and intertrochanter (AUC = 0.738) and significant NRI (0.177, 0.149, and 0.195, respectively) were observed compared with FN-aBMD (AUC = 0.701), but not TH-aBMD. vBMD obtained from 3D modeling using routinely obtained hip DXA images significantly improved hip fracture risk prediction over conventional FN-aBMD, but not TH-aBMD. The Japanese Population-Based Osteoporosis (JPOS) Cohort Study was retrospectively registered as UMIN000032869 in the UMIN Clinical Trials Registry on July 1, 2018.

Visceral and subcutaneous adipose tissue, which one induced thyroid dysfunction in patients with morbid obesity.

Thyroid dysfunction in patients with morbid obesity usually resolves after bariatric surgery. However, the role of diverse types of adipose tissue in the process remains unknown. We aim to investigate the effects of visceral and subcutaneous fat on thyroid function in a Chinese population with morbid obesity who underwent sleeve gastrectomy (SG). University hospital, Shanghai, China METHODS: Repeated measurement data of thyroid hormone and body fat were collected at 0, 3, 6, 12, 24, and 36 months after sleeve gastrectomy. Dual-energy X-ray absorptiometer and quantitative computerized tomography (CT) were used to compute visceral fat and subcutaneous fat. Repeated measures correlation (rmmcorr) package was employed for correlation analysis with generalized additive mixed model (GAMM) determining the independent factors. Thyroid stimulating-hormone (TSH) showed notable decrease at 36 months after surgery, coupled with reduction of BMI (38.08 kg/cm2 versus 24.28 kg/cm2), C-reactive protein (CRP), visceral adipose tissue (786.74 cm2 versus 367.44 cm2), body fat rate, and waistline (118.13 cm versus 100.87 cm). Only visceral fat, diabetes, and CRP proved to be independent variables for TSH decline, without correlation with subcutaneous fat. The present study is first to report the effects of different types of body fat on thyroidfunction in a Chinese population with morbid obesity, revealing that loss of visceral fat is the key to improving endocrine and metabolic activity after bariatric surgery.

Effects of progressive elastic band resistance exercise for aged osteosarcopenic adiposity women.

Osteosarcopenic adiposity (OSA), which is described as the concurrent occurrence of osteopenia, sarcopenia, and adiposity, can lead to frailty and increase the risk of physical disability in elderly women. Progressive elastic band resistance exercise training (peRET) is considered a safe and feasible exercise intervention for elderly women with sarcopenic obesity. This study investigated the effects of elastic band resistance exercise on the physical capacity and body composition of elderly women with osteosarcopenic adiposity. A total of 15 and 12 women were randomly assigned to the experimental (12weeks of resistance exercise) and control groups (no exercise intervention), respectively. Lean mass (measured using a dual-energy X-ray absorptiometer) and physical capacity assessments (such as timed up and go test and single leg stance tests) were conducted at baseline, 12weeks (end of intervention), and 6months after the intervention. Outcome differences within the study and control groups were analyzed using repeated-measures analysis of variance with a post-hoc test. The Mann-Whitney U test was used to examine differences between groups at different time points. After the intervention, no body composition changes in muscle mass and fat were observed between the study and control groups. Moreover, muscle mass and fat body composition did not significantly differ at different time points. The bone density was higher in the study group, with a higher T-score than their baseline values, but did not significantly differ compared with the control group. The study group exhibited more improved physical function than the control group, but the effect did not last after 6months of follow-up. A 12-week progressive elastic band resistance training program effectively increased the physical capacity and improved the bone density; however, without persistent training, the positive effect diminished at 6-month follow-up.

Using dual energy X-ray absorptiometry to estimate commercial cut weights at abattoir chain-speed

This experiment assessed the ability of an on-line dual energy x-ray absorptiometer (DEXA) installed at a commercial abattoir to determine commercial cut weights in lamb carcases at abattoir chain-speed. 200 lamb carcases were scanned using a DEXA that was trained to predict the computed tomography determined proportions of fat, lean, and bone. Models were then trained using hot carcase weight and, DEXA fat% value or GR tissue depth to predict cut weight. Results from validation tests of DEXA models demonstrated excellent precision for predicting cut weight, in most cases describing more than 85% of the variation, and RMSE values that represented between 5 and 13% of the average weight of each cut. For most cuts these weight predictions were superior to those informed by GR tissue depth. This precision was maintained upon validation. Additional analyses utilised pixel information from the fore, saddle, and hind sections of DEXA images. This further enhanced the predictive power of cut weight models.

Diagnostic Central Obesity Indexes Cut - Off Point Values Determined with Dual-Energy X-Ray Absorptiometry in Cushing's and Obese Women.

The aim of this study was to develop quantiative criteria for defining visceral obesity and to establish dual-energy X-ray absorptiometric (DXA) diagnostic cut-off points (CP) for normal and abnormal values of the central obesity indexes (COI) that best differentiate extreme visceral obesity in Cushing's syndrome (CS) from non CS obese and non obese women. COI1-4 values calculated as a ratio of android to gynoid tissue mass, fat mass and their % were determined in 4 groups, each consisting of 18 women: 1st group of CS, 2nd group of obese women (O1) not different according to their age and BMI from CS, 3rd group of obese women (O2) with BMI of 35 ± 1.2 kg and 4th group of non obese healthy women (C) with normal BMI. Diagnostic accuracy (DG) of CP values of COI1m-4m indexes of abdominal obesity and CP values of COI1n-4n indexes of normal body fat distribution (BFD) was determined. COI1-4 indexes values were highly significantly different among the 4 examined groups and were significantly highest in CS patients and lowest in group C (p < 0.0001). COI1m-4m CP values differentiated extreme visceral, abdominal obesity in CS with highest DG as well as COI1n-4n CP values differentiated normal BFD in group C. COI1m CP of 0.55 best differentiated CS from O1 for DG of 100%. COI2n of 0.38 best differentiated C from CS and O2 for highest DG of 100% compared to O1 because of the significantly higher BMI and COI1n-4n values in O2 that were associated with more pronounced abdominal obesity and highly significantly positive correlation with BMI. DXA cut-off point values of indexes COI1m-4m and COI1n-4n were established as diagnostic indexes and criteria useful in discovering extreme abdominal and normal BFD. COI1m CP value of 0.55 was discovered as a diagnostic criterion of extreme abdominal obesity and COI2n of 0.38 as a diagnostic criterion of normal BFD that excluded abdominal obesity. The other indexes COI1m-4m and COI1n-4n CP values had also high DG in discovering abdominal and normal body fat distribution.

D2 dopamine receptor gene (DRD2) Taq1A (rs1800497) affects bone density

Schizophrenia patients are susceptible to lower bone mineral density (BMD). However, studies exploring the genetic effects are lacking. Genes that affect the activity of antipsychotics may be associated with BMD, particularly in patients receiving long-term antipsychotic treatment. We aimed to explore the relationship between the dopamine receptor D2 (DRD2) gene Taq1A (rs1800497) polymorphism and BMD in chronic schizophrenia patients. We recruited schizophrenia patients (n = 47) and healthy controls (n = 39) from a medical center in Taiwan and collected data that may affect BMD. Patients’ BMD was measured by dual-energy X-ray absorptiometer (DEXA). DRD2 rs1800497 was genotyped through polymerase chain reaction–Restriction Fragment Length Polymorphism (PCR–RFLP). Among all participants, subjects with DRD2 rs1800497(T;T) allele had lower DEXA T score and DEXA Z score compared to those with rs1800497(C;T) and rs1800497(C;C) alleles (p = 0.008, 0.003, respectively). In schizophrenia patients, subjects with rs1800497(T;T) allele also had lower DEXA Z score compared to the other two alleles (p = 0.045). Our findings suggest that individuals with the DRD2 rs1800497(T;T) had lower BMD than those with the rs1800497(C;T) and rs1800497(C;C) genotypes. Therefore, genes should be considered as one of the risk factors of lower BMD.

Comparison of the associations between appendicular lean mass adjustment methods and cardiometabolic factors

Background and aimsTo compare the cross-sectional and longitudinal associations between appendicular lean mass (ALM) and cardiometabolic risk factors according to body-size adjustment methods and the contributions of genetic and/or environmental factors to the correlations between those traits. Methods and resultsRegression coefficients per sex-specific 1 standard deviation in bodyweight (wt), body mass index (BMI), or height-squared (ht2) adjusted ALM (assessed using a dual-energy X-ray absorptiometer (DXA) and a bioelectrical impedance analyzer (BIA) at baseline)/changes in these indices (assessed using BIA) were compared in terms of their associations with blood pressure (BP), lipid profiles, and insulin resistance profiles in 2655 participants for cross-sectional analysis and 332 participants for longitudinal analysis (follow-up time, 32.2 ± 7.9 months). A bivariate genetic analysis of the genetic/environmental cross-trait correlations was conducted to determine their cross-sectional relationships. After adjusting for sociodemographic factors, health behaviors, and BMI in the analysis for ALM/ht2, ALM/wt and ALM/BMI had favorable associations with all cardiometabolic risk factors, while ALM/ht2 had favorable associations with some risk factors. In longitudinal associations, changes in ALM/wt and ALM/BMI had inverse associations with increments of lipid profiles, insulin, and homeostasis model assessment of insulin resistance (HOMA), while change in ALM/ht2 did not have associations with increments of cardiometabolic risk factors. ALM/ht2 had genetic correlations with seven of nine risk factors; ALM/wt and ALM/BMI had correlations with three and one risk factors, respectively. ConclusionALM/wt and ALM/BMI are better indicators for cardiometabolic risk factors; genetic factors may contribute more to the correlations between ALM/ht2 and those traits.

Protein-enriched Meals At Breakfast Increase Muscle Accretion In Healthy Young Men Undergoing 12-week Resistance Training

While daily protein intake has been reported to be essential for muscle regulation, the breakdown of daily protein intake in individuals is typically the lowest at breakfast and skewed towards dinner. Skewed protein intake pattern and inadequate protein intake at breakfast was reported to be a negative factor for muscle regulation, and no study has examined the effects of protein intake pattern at each meal on anabolic response such as muscle hypertrophy. PURPOSE: This study aimed to examine whether a protein-enriched meal at breakfast to achieve adequate protein intake at all 3 meals is more effective for muscle accretion compared to typical protein intake pattern, skewed protein intake towards dinner. METHODS: This 12-week, parallel-group randomized clinical trial included 26 men (means ± SEs; age, 20.8 ± 0.4 years; BMI, 21.8 ± 0.4 kg/m2). The participants were divided into 2 groups: HBR (n = 12), consuming a protein-enriched meal at breakfast to achieve adequate protein intake at all 3 meals; LBR (n = 14), consuming a provided meal at breakfast to achieve adequate protein intake at lunch and dinner. The participants performed 12-week supervised resistance training (RT) program 3 times/week (3 sets of 8-12 repetitions at 75-80% of one repetition maximum for 5 exercises). We used dual-energy X-ray absorptiometer to measure total fat-free mass (TotalFFM). RESULTS: No significant difference in TotalFFM was observed between the 2 groups at baseline (HBR vs LBR: 52.4 ± 1.3 vs 53.4 ± 1.2 kg). After completing the 12-week diet plan and RT program, both the groups gained significant TotalFFM (2.1 ± 0.2 kg, 4.0 ± 0.4%), with the HBR group having greater changes in TotalFFM than the LBR group [HBR vs LBR, 2.5 ± 0.3 vs 1.8 ± 0.3 kg; P = 0.056; cohen’s d = 0.795 (Large effect size)]. CONCLUSIONS: Protein-enriched meal at breakfast to achieve adequate protein intake at all three meals is more effective than skewed protein intake at dinner for RT-induced muscle hypertrophy. This work was supported by the Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research (no. 17H02183 to S. Fujita).

Protective role of serum uric acid for bone loss in postmenopausal women

Researchers had found that there is an association between oxidative stress and osteoporosis. Postmenopausal osteoporosis causes major public health problems. Since Uric acid has strong antioxidant properties, it will improve bone quality. This cross-sectional observational study was done to determine the association of Uric Acid and Bone Mineral Density of 75 healthy postmenopausal women who came for a master health checkup. The mean age was 60.5 years. After ethical clearance and informed consent, women were recruited for the study at Saveetha Medical Hospital Chennai. Women with medical conditions or who were using drugs affecting bone metabolism or uric acid were excluded. Basic investigations were Hb, serum UA, blood urea, serum creatinine, serum calcium and alkaline phosphatase, blood glucose and glycosylated Hb. Total Cholesterol, HDL, LDL, VLDL, 25 hydroxy Vitamin D were also done. Serum UA levels were graded as &lt;3.9, 3.9–4.9, 5–6.1, and ≥6.2 mg/dl. Bone Mineral Density (BMD) was calculated with Dual Energy X-ray Absorptiometer (DXA). Osteoporosis was defined as BMD T-score −2.5 and below. BMD with a T-score of -1 −2.5 was classified as osteopenia (WHO). In women with high UA, there were significantly higher levels of low-density lipoprotein, and calcium, as compared to women with low UA group (p&lt;0.05). High UA group, as compared to the low UA group, also had lower levels of high-density lipoprotein (p&lt;0.001). Women with higher Uric acid levels had lower BMI, lesser years of duration of Menopause and increased BMD. Serum UA level had a positive correlation with the Lumbar BMD T score and Right Femoral Neck BMD T Score. In UA &gt;5.4mg/dl group Osteoporosis was nil.

Validation of a Multielectrode Bioelectrical Impedance Analyzer With a Dual-Energy X-Ray Absorptiometer for the Assessment of Body Composition in Older Adults.

Changes in body composition are related to mobility, fall risk, and mortality, especially in older adults. Various devices and methods exist to measure body composition, but bioelectrical impedance analysis (BIA) has several advantages. The purpose of this study was to validate a common BIA device with a dual-energy X-ray absorptiometer (DXA) in older adults and develop prediction equations to improve the accuracy of the BIA measurements. The participants were 277 older adults (162 women and 115 men; age 73.9 ± 5.8 years) without a history of cancer and without a history of severe medical or mental conditions. Individuals fasted 12hr before BIA and DXA measurement. The correlations between the two methods for appendicular lean mass (ALM), fat-free mass (FFM), and percentage body fat (%BF) were .86, .93, and .92, respectively, adjusting for age and sex. The mean percentage error (DXA-InBody) and mean absolute percentage error were -12% and 13% for ALM, -13% and 13% for FFM, and 16% and 17% for %BF. The prediction equations estimated ALM, FFM, and %BF; sex was coded as 1 for male and 0 for female: DXAALM=0.0673+(0.6732×BIAALM)+(2.33507×sex)+(0.13349×BMI),R2=.94;DXAFFM=0.72323+(0.72384×BIAFFM)+(3.675012×sex)+(0.2816×BMI),R2=.97;andDXA%BF=15.8896+(0.64694×BIA%BF)-(3.99945×sex)+(0.13824×BMI),R2=.91 Although highly correlated, BIA overestimated FFM, and ALM and underestimated %BF compared with DXA. An application of prediction equations eliminated the mean error and reduced the range of individual error across the sample. Prediction equations may improve BIA accuracy sufficiently to substitute for DXA in some cases.