Body Dual-energy X-ray Absorptiometry Research Articles

Discovering the Individualized Factors Associated with Sarcopenia and Sarcopenic Obesity Phenotypes-A Machine Learning Approach.

The literature shows how sarcopenia often occurs along with different phenotypes based either on the concomitant presence of adipose tissue excess (i.e., sarcopenic obesity, SO), or osteopenia/osteoporosis (osteosarcopenia, OS), or the combination of the two conditions, so-called osteosarcopenic obesity (OSO). This research aimed to assess the prevalence of sarcopenia phenotypes (SO, OS, OSO), their associated risk factors and their health impact in a population of out- and inpatients living in the North of Italy. Male and female subjects aged ≥18 years were enrolled for the study. A blood sample was collected to measure targeted blood makers. A comprehensive anthropometric clinical assessment (height, weight, Body Mass Index, BMI and Dual Energy X-ray Absorptiometry, DXA) was performed to measure ponderal, bone, fat, and muscle status. A total of 1510 individuals participated to the study (females, n = 1100; 72.85%). Sarcopenia was the most prevalent phenotype (17%), followed by osteosarcopenia (14.7%) and sarcopenic obesity. Only 1.9% of the sample was affected by OSO. According to logistic regression analysis, sarcopenia was associated with age, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) (positively) and BMI, Iron (Fe), Total Cholesterol, albumin (%), albumin (g), and gamma proteins (negatively). Sarcopenic obesity was associated with age, ferritin, ESR, CRP (positively) and BMI, Fe, and albumin (%) (negatively). Osteosarcopenia was associated with age, ESR (positively) and BMI, Total Cholesterol, albumin (%), albumin (g), and Ca (negatively). Osteosarcopenic obesity was associated with glycemia and gamma-glutamyl transferase (gGT) (positively). According to random forest analysis, a higher BMI was the most important protective factor for sarcopenia, for sarcopenic obesity (along with Iron) and for osteosarcopenia (along with albumin). Moreover, osteosarcopenic obesity was positively associated with GgT and glycaemia. The possibility of gaining such information, especially in the younger population, could help to prevent the onset of such diseases and best fit the patient's needs, according to a precision-medicine approach.

Effect of six weeks of resistance training on bone preservation in older adults: a randomized control trial.

It has been established that chronic resistance exercise contributes to positive changes to bone in older adults. This study evaluated the effect of 6weeks of resistance exercise with either elastic bands or dumbbells vs. a control period on bone morphology of older adults. Fifty-seven adults (mean ± SD; age = 66.5 ± 7.09 yrs; height = 165.2 ± 10.6cm; body mass = 74.5 ± 14.6kg) were randomized into three groups (dumbbell, elastic, or control). Participants underwent a total body dual-energy X-ray absorptiometry (DXA) scan for total body and segmental bone mineral content (BMC) and bone mineral density (BMD) before and following 6-week intervention. Age-matched Z-scores for BMD and BMC were recorded. Data were analyzed using two-way repeated measures ANOVAs and 0.05 significance level. BMCarm improved for the dumbbell group (p = 0.016) after the training, with no change in BMD for any group (p > 0.05). Additionally, significant (time x treatment group) interaction (p = 0.024) of age-matched Z-scores indicated an improvement in only the dumbbell group after 6weeks (p = 0.015), with no change in the elastic group despite them having greater Z-scores than the control group. This study is the first to demonstrate acute normative adaptations as dumbbell-based programs may promote positive maintenance of bone metrics over 6weeks, despite the lack of significant change in absolute BMC or BMD. Adults did not lose relative bone mass with acute exercise using dumbbells as the external load applied and this may lead to positive changes following chronic training. There was no bone-related impact from elastic bands, suggesting a weighted load or force produced relative to gravity is beneficial.

OR10-01 Discordance Between Body Mass Index and Dual-energy X-ray Absorptiometry Based Adiposity Measures Among United States Adults

Abstract Disclosure: A. Visaria: None. T. Sindhu: None. T. Dharamdasani: None. Background: Body Mass Index (BMI) is a widely used, albeit flawed, surrogate measure for adiposity. Whether the extent of discordance between BMI, true adiposity, and body fat distribution is different by race is unknown. We sought to describe the racial differences in BMI and dual-energy x-ray absorptiometry (DEXA) based adiposity measures among a nationally representative sample of adults. Methods: We identified non-pregnant U.S. adults 20-59 years from the 2011-2018 National Health and Nutrition Examination Survey (NHANES) with whole body DEXA scan data. BMI was categorized into ethnicity-specific (non-Asian: underweight<18.5, normal=18.5-24.9, overweight=25-29.9, obese≥30 kg/m2, Asian: <18.5, 18.5-22.9, 23-27.4, 27.5+) categories. DEXA scans were performed using Hologic Discovery densitometers, analyzed by Hologic software (APEX v4.0), and verified by expert reviewers. Total body fat % (BF%), android-to-gynoid fat ratio, and leg fat % (% of total BF in legs) were calculated. Among adults classified as normal/overweight via BMI, we estimated odds of obesity (BF% ≥25% in male, ≥32% in female) by race (non-Hispanic White [NHW], non-Hispanic Black [NHB], Asian, Hispanic, and Other) using multivariable logistic regression. We estimated mean DEXA adiposity measures by race using multivariable linear regression. Analyses were adjusted for confounders & the survey design. Results: Among 9,784 participants (mean age 39y [SD, 11], 61% NHW, 49% female), 36% had BMI≥30 and 74% had obesity per BF%. Among normal BMI adults, 44% of NHW, 27% of NHB, 49% of Hispanic, and 49% of Asians had obesity as per BF% (p<0.001). Among overweight BMI adults, the adjusted mean (SE) android-to-gynoid fat ratio was 1.01 (0.01) for NHW, 0.97 (0.01) for NHB, 1.05 (0.01) for Hispanics, and 1.04 (0.01) for Asians (p<0.001). Among normal BMI adults, the adjusted mean (SE) android-to-gynoid fat ratio was 0.84 (0.01) for NHW, 0.85 (0.01) for NHB, 0.89 (0.01) for Hispanics, and 0.91 (0.01) for Asians (p<0.001 for NHW vs. Asian, Hispanic). The adjusted mean leg fat % was 39.2% (0.1) for NHW, 40.9% (0.2) for NHB, 37.3% (0.2%) for Hispanics, and 36.7% (0.2) for Asians (p<0.001), Overweight BMI NHBs had 58% lower odds of obesity compared to NHW (aOR [95% CI]; NHB: 0.42 [0.32, 0.54], Hispanic: 1.26 [0.97, 1.64], Asian: 0.81 [0.63, 1.05]). Conclusion: Nearly 3 in 4 young-to-middle-aged U.S. adults have obesity via total body fat percentage estimated from DEXA scans. Despite ethnicity-specific BMI cutoffs, normal BMI Asian Americans, as well as Hispanics, were more likely to have obesity, and more likely to have a greater proportion of abdominal fat than NHW. On the other hand, NHB had significantly lower likelihood of obesity at normal/overweight BMI ranges, and lower proportion of abdominal fat. These suggest that BMI alone may not be sufficient to detect metabolically unhealthy adiposity, especially in Asian Americans and Hispanics. Presentation: Friday, June 16, 2023

SAT399 Are Gender-affirming Hormone Therapy Duration And Body Mass Index Associated With Bone Mineral Density In Transgender And Gender Diverse Adults?

Abstract Disclosure: S.J. Iwamoto: None. J.D. Rice: None. N.J. Nokoff: None. K.L. Moreau: None. M. Cornier: None. M.E. Wierman: None. M.P. Mancuso: None. M.S. Rothman: None. Background: Sex steroids play crucial roles in bone mineral density (BMD) accrual and maintenance. Data on gender-affirming hormone therapy’s (GAHT) bone effects in transgender and gender diverse (TGD) adults have been limited to non-U.S. cohorts with higher gonadectomy and smoking rates. A higher prevalence of low BMD has been seen in TGD adults prior to initiating feminizing, compared to masculinizing, GAHT (fGAHT, mGAHT). Both fGAHT and mGAHT maintain lumbar spine (LS) BMD and increase Z-scores. Adult femoral neck (FN) and total hip (TH) site data are limited. The associations of GAHT duration and body mass index (BMI) with bone health among U.S. TGD adults are understudied. Objectives: To evaluate the associations between BMDs and Z-scores with GAHT duration and BMI among nonsmoking TGD adults aged 18-40 years, without prior gonadectomy, taking estrogen+spironolactone (fGAHT) or testosterone (mGAHT) for >1 year. Hypotheses: BMDs and Z-scores among fGAHT and mGAHT are within expected male and female reference ranges. Increasing GAHT duration and BMI are each associated with increasing BMDs and Z-scores at FN, TH and LS sites. Methods: Cross-sectional study of FN, TH, and LS bone density outcomes measured by total body dual-energy X-ray absorptiometry (DXA) in 30 adults receiving GAHT within a metropolitan area. Means±standard deviations were calculated. Associations between BMDs and Z-scores and the predictors, GAHT duration and BMI, were estimated for each of the three sites using linear regression. Results: Among fGAHT (n=15, n=0 non-White or Hispanic, age 28.7±4.8 years, GAHT 3.1±2.1 years, estradiol 189.7±119.6 pg/mL, total testosterone 97.6±99.5 ng/dL), mean BMI was in the overweight range (27.6±6.4 kg/m2) and mean total body percent fat was 33.7±7.3%. Among mGAHT (n=15, n=3 non-White, n=2 Hispanic, age 28.5±5.7 years, GAHT 4.0±2.0 years, estradiol 46.8±24.0 pg/mL, total testosterone 544.6±332.8 ng/dL), mean BMI was also in the overweight range (BMI 25.3±5.9 kg/m2) and mean total body percent fat was 29.8±7.1%. Both fGAHT and mGAHT groups had BMDs and Z-scores within expected male and female reference ranges at all three sites. Increasing BMI among mGAHT, but not fGAHT, was associated with increasing FN and TH, not LS, BMDs and Z-scores using male and female references (p<0.05). GAHT duration was not associated with BMDs or Z-scores. Conclusions: Z-scores in nonsmoking TGD adults taking fGAHT or mGAHT for >1 year, without prior gonadectomy, and with average BMIs in the overweight range, were reassuringly within the expected ranges for age. Increasing BMI, but not GAHT duration, was associated with higher FN and TH, but not LS, BMDs and Z-scores among mGAHT only. Larger studies, especially prospective, are needed to understand the associations between body composition changes (for example, lean mass and fat mass), normal or low BMIs, and gonadectomy with BMDs and Z-scores. Presentation: Saturday, June 17, 2023

Multi-target landmark detection with incomplete images via reinforcement learning and shape prior embedding.

Medical images are generally acquired with limited field-of-view (FOV), which could lead to incomplete regions of interest (ROI), and thus impose a great challenge on medical image analysis. This is particularly evident for the learning-based multi-target landmark detection, where algorithms could be misleading to learn primarily the variation of background due to the varying FOV, failing the detection of targets. Based on learning a navigation policy, instead of predicting targets directly, reinforcement learning (RL)-based methods have the potential to tackle this challenge in an efficient manner. Inspired by this, in this work we propose a multi-agent RL framework for simultaneous multi-target landmark detection. This framework is aimed to learn from incomplete or (and) complete images to form an implicit knowledge of global structure, which is consolidated during the training stage for the detection of targets from either complete or incomplete test images. To further explicitly exploit the global structural information from incomplete images, we propose to embed a shape model into the RL process. With this prior knowledge, the proposed RL model can not only localize dozens of targets simultaneously, but also work effectively and robustly in the presence of incomplete images. We validated the applicability and efficacy of the proposed method on various multi-target detection tasks with incomplete images from practical clinics, using body dual-energy X-ray absorptiometry (DXA), cardiac MRI and head CT datasets. Results showed that our method could predict whole set of landmarks with incomplete training images up to 80% missing proportion (average distance error 2.29 cm on body DXA), and could detect unseen landmarks in regions with missing image information outside FOV of target images (average distance error 6.84 mm on 3D half-head CT). Our code will be released via https://zmiclab.github.io/projects.html.

Obesity and sarcopenic obesity characterized by low-grade inflammation are associated with increased risk for major depression in women.

We aimed to determine women's risk of major depressive disorder (MDD) in relation to obesity phenotypes characterized by levels of circulating high-sensitivity C-reactive protein (hsCRP). This population-based retrospective cohort study comprised 808 women (ages 20-84 y) recruited 1994-1997 and followed for a median 16.1 y (IQR 11.9-16.8). At baseline, body fat and lean tissue mass were measured by whole body dual-energy x-ray absorptiometry (DXA). Obesity was identified as high fat mass index (>12.9 kg/m2), body fat percentage (≥35%) and body mass index (≥30 kg/m2); sarcopenic obesity referred to a high ratio fat mass/fat-free mass (≥0.80). Systemic inflammation was operationalized as serum hsCRP concentration in the upper tertile (>2.99 mg/L). Obesity phenotypes were: non-obese + lowCRP, non-obese + highCRP, obese + lowCRP, and obese + highCRP. During follow-up, the Structured Clinical Interview for DSM-IV-TR (SCID-I/NP) was used to identify lifetime history of MDD and age of onset. Poisson regression models were used to estimate the MDD rate for each obesity phenotype during follow-up. Demographic, health and lifestyle factors were tested as potential confounders. During 11,869 p-y of follow-up, 161 (19.9%) women experienced an MDD episode. For obesity phenotypes based on fat mass index, models adjusted for baseline age and prior MDD, and non-obese + lowCRP as reference, RR for non-obese + highCRP was 1.21 (95% CI 0.80, 1.82), obese + lowCRP 1.46 (0.86, 2.47) and obese + highCRP 1.56 (1.03, 2.37). Patterns were similar for obesity by body fat percentage, body mass index and sarcopenic obesity. Consistently across different obesity definitions, this longitudinal study reports that women with both obesity and systemic inflammation are at increased risk of subsequent MDD. Future research should examine whether tackling this metabolically unhealthy obesity type - through, for example, lifestyle or medication approaches - can reduce depression risk.

Body metrics are associated with clinical, free-living, and self-report measures of mobility in a cohort of adults with obesity and multiple sclerosis

BackgroundObesity is associated with multiple sclerosis (MS) onset and may contribute to more rapid disability accumulation. Whether obesity impacts mobility in MS is uncertain. Some studies find that obesity in MS is associated with poorer mobility; other studies find no relationship. Discrepant findings may be due to differences in measurement and methodology. In the present study, we employ a comprehensive battery of anthropometric and mobility measures in a sample of people with MS and obesity. MethodsParticipants with MS (N = 74) completed a battery of adiposity measurements (weight, height, waist circumference, and full body dual-energy x-ray absorptiometry [DXA] scans). They also completed validated clinical, free-living (accelerometry), and self-report measures of mobility. Spearman's Rho correlations were used to examine the associations between mobility and obesity measures with Benjamini and Hochberg correction for multiple comparisons. Multiple linear regression was used to examine if adiposity predicted mobility outcomes in people with MS when controlling for age and disease duration. ResultsThe majority of participants (n = 70) were diagnosed with relapsing-remitting MS and reported mild MS-related disability on the Patient Determined Disease Steps (M = 0.77, SD = 1.1). Median BMI was 35.8 (SD = 5.4). Higher percentage body fat (measured via DXA) was associated with poorer self-reported physical functioning (rs = −0.52, p <0.001), less moderate-to-vigorous physical activity (rs = −0.24, p = 0.04), and worse performance on the Six Minute Walk Test (6MWT; rs = −0.44, p <0.001), the Timed 25 Foot Walk (T25FW; rs = 0.45, p <0.001), and the Timed Up and Go test (TUG; rs = 0.35, p = .003). Higher BMI and waist-to-height ratio (WtHR) were associated with worse outcomes on the 6MWT (BMI; rs = −0.35, p <0.01, WtHR; rs = −0.43, p <0.001), T25FW (BMI; rs = 0.32, p <0.01, WtHR; rs = 0.38, p <0.001), and the SF-36 (BMI; rs = −0.29, p <0.005, WtHR; rs = −0.31, p <0.05). Percentage body fat accounted for an additional 17 % of the variance in the T25FW and 6MWT performance, after controlling for age and disease duration. ConclusionHigher BMI, WtHR, and percentage body fat were associated with lower levels of mobility (T25FW and 6MWT) in people with MS who have class I, class II, and class III obesity. Higher percentage body fat was associated with significantly worse performance on clinical, free-living, and self-report measures of mobility in people with MS even when accounting for participant age and disease duration. These findings suggest that people with MS and obesity may show improved mobility with weight loss.

A nude mutant rat derived from Sprague Dawley-National Institute of Nutrition rat colony with normal thymus: A potential model for noncommunicable diseases.

A spontaneous mutant rat with a hairless phenotype and an intact thymus was discovered in a long-standing Sprague Dawley-National Institute of Nutrition (SD/NIN) rat colony at a national animal resource facility. We conducted extensive phenotypic and biochemical analyses on this mutant strain to determine its suitability as a preclinical model for immunocompetent testing in noncommunicable disease research. We subjected the mutant rats to strict and frequent phenotypic and genetic surveillance to accomplish this objective. The animals were assessed for food intake, body weight, blood cell profile, clinical chemistry, adipose tissue deposition, and bone mineral density (BMD) using total electrical body conductance (TOBEC) and dual-energy X-ray absorptiometry (DXA) analysis. Initially, only two hairless mutant rats, a male and a female, were born from a single dam in the SD/NIN rat strain. However, the results indicate that the mutant colony propagated from these unique pups displayed distinct phenotypic features and exhibited differences in feeding behavior, weight gain, and clinical biochemistry. The food conversion rate was significantly higher in nude females (2.8-fold) while 26% lower in nude males. Both sexes of nude rats had significantly higher triglycerides and lower glucose levels in females. However, glucose levels did not change in male nude rats. Furthermore, nude female and male rats had significantly lower fat (TOBEC) and bone mineral content (DXA). Nonetheless, BMD was only slightly lower (7%-8%) compared to the heterozygous groups. These findings indicate that the spontaneous mutant rat has the potential to serve as an immunopotent and modulatory testing system in pharmacokinetics/pharmacodynamics and toxicology, which can be further explored for therapeutic drug discovery.

Low skeletal muscle mass as an early sign in children with fabry disease

Background & aimsFabry disease (FD) is a rare X-linked metabolic storage disorder due to the deficiency of lysosomal α-galactosidase A which causes the accumulation of glycosphingolipids throughout the body. Underweight and low BMI have been occasionally reported in FD patients previously. Whether underweight is common in the early stage of FD and body composition analysis to determine the cause have not been reported.MethodsChildren who were diagnosed with FD in the Children’s Hospital of Zhejiang University School of Medicine from July 2014 to December 2022 were enrolled. Clinical data were obtained from medical records. Whole body dual energy X-ray absorptiometry scans (DXA) were used to assess body composition (fat mass, FM; fat free mass, FFM and bone mass) according to the International Society of Clinical Densitometry’s standard operating method. Whole body muscle mass was calculated as fat-free mass minus bone mass. Appendicular skeletal muscle mass (ASM) was calculated as the sum of the arm and the leg muscle mass. The FM, FFM, ULSM and LLSM indices were calculated by dividing the total FM, FFM, and upper and lower limb skeletal muscle mass (ULSM and LLSM) by the height squared.ResultsA total of eighteen children (14 boys and 4 girls) were enrolled. Thirteen boys had the classical phenotype, and five children (1 boy with the N215S mutation and 4 girls) had the late-onset phenotype. Seven children with the classical phenotype (53.8%) and two of the five children (40%) with the late-onset phenotype had abnormal BMIs. Sixteen of the eighteen children (88.9%) had a height in the normal range, suggesting that low BMI was mainly due to underweight. By DXA body composition analysis, the FMI was abnormal in 3 children (2 boys and 1 girl), and the FFMI was abnormal in 12 children (9 boys and 3 girls). For the classical phenotype, 2 of the 13 children (15.4%) had abnormal FMI values, while 10 (76.9%) had abnormal FFMI values. Eight patients (61.5%) with the classical phenotype had a significant reduction in muscle mass index, ASM index and LLSM index values compared with age- and sex- matched Chinese controls. Late-onset patients also had mild low skeletal muscle mass compared to controls. The results suggested that low skeletal muscle mass is common in early FD.ConclusionsThis is the first study to examine body composition and muscle mass in early Fabry disease patients. Low skeletal muscle mass is a common early symptom in children with Fabry disease, suggesting that skeletal muscle is significantly affected in the early stages of FD.

Bone mineral density and its relationship with ground reaction force characteristics during gait in young adults with Prader-Willi Syndrome

IntroductionThe incidence of osteopenia and osteoporosis is of concern in adults with Prader-Willi syndrome (PWS). Walking generates reaction forces that could stimulate bone mineralization and is popular in people with PWS. This study compared bone parameters and ground reaction forces (GRF) during gait between young adults with PWS and without PWS and explored associations between bone and GRFs during gait. Methods10 adults with PWS, 10 controls with obesity (OB) and 10 with normal weight (NW) matched on sex participated. Segmental and full body dual-energy x-ray absorptiometry scans provided femoral neck, spine, total body minus the head bone mineral density (BMD), bone mineral content (BMC). Vertical GRF, vertical impulse, posterior force and negative impulse were measured during 5 walking trials at a self-selected speed along a 10 m runway. ResultsMultivariate analyses of variance showed that adults with PWS (n = 7–8) had hip and body BMD and BMC comparable (p > .050) to NW and lower (p < .050) than OB. Adults with PWS showed slower speed than NW (p < .050) but similar to OB (p > .050). Adults with PWS presented lower absolute vertical GRF, vertical impulse and negative impulse than OB (p < .050). Pearson r correlations (p < .050) in those with PWS (n = 7–8) indicated that femoral neck BMC was associated with vertical GRF (r = 0.716), vertical impulse (r = 0.780), posterior force (r = −0.805), and negative impulse (r = −0.748). Spine BMC was associated with speed (r = 0.829) and body BMD was associated with speed (r = 0.893), and posterior force (r = −0.780). ConclusionsIncreased BMC in the femoral neck and body were associated with larger breaking forces during walking, a phenomenon normally observed at greater gait speeds. Faster walking speed was associated with greater BMC in the spine and body. Our preliminary results suggest that young adults with PWS could potentially benefit from faster walking for bone health; however, larger prospective studies are needed to confirm this.

Automated measurement of size of spinal curve in population-based cohorts: Validation of a method based on total body dual energy X-ray absorptiometry scans.

Scoliosis is spinal curvature that may progress to require surgical stabilisation. Risk factors for progression are little understood due to lack of population-based research, since radiographs cannot be performed on entire populations due to high levels of radiation. To help address this, we have previously developed and validated a method for quantification of spinal curvature from total body dual energy X-ray absorptiometry (DXA) scans. The purpose of this study was to automate this quantification of spinal curve size from DXA scans using machine learning techniques. To develop the automation of curve size, we utilised manually annotated scans from 7298 participants from the Avon Longitudinal Study of Parents and Children (ALSPAC) at age 9 and 5122 at age 15. To validate the automation we assessed (1) agreement between manual vs automation using the Bland-Altman limits of agreement, (2) reliability by calculating the coefficient of variation, and (3) clinical validity by running the automation on 4969 non-annotated scans at age 18 to assess the associations with physical activity, body composition, adipocyte function and backpain compared to previous literature. The mean difference between manual vs automated readings was less than one degree, and 90.4% of manual vs automated readings fell within 10°. The coefficient of variation was 25.4%. Clinical validation showed the expected relationships between curve size and physical activity, adipocyte function, height and weight. We have developed a reasonably accurate and valid automated method for quantifying spinal curvature from DXA scans for research purposes.

Metformin versus insulin for gestational diabetes: Adiposity variables and adipocytokines in offspring at age of 9 years

AimsTo compare body composition, visceral adiposity, adipocytokines, and low-grade inflammation markers in prepubertal offspring of mothers who were treated with metformin or insulin for gestational diabetes mellitus (GDM). Methods172 offspring of 311 mothers randomized to receive metformin (n = 82) or insulin (n = 90) for GDMwere studied at 9 years of age (follow-up rate 55%). Measurements included anthropometrics, adipocytokines, markers of the low-grade inflammation, abdominal magnetic resonance imaging (MRI), magnetic liver spectrometry (MRS), and whole body dual-energy X-ray absorptiometry (DXA). ResultsSerum markers of low-grade inflammation, visceral adipose tissue volume, total fat percentage, and liver fat percentage were similar between the study groups. Serum adiponectin concentration was higher in children in the metformin group compared to insulin group (median 10.37 vs 9.50 µg/ml, p = 0.016). This difference between groups was observed in boys only (median 12.13 vs 7.50 µg/ml, p < 0.001). Leptin/adiponectin-ratio was lower in boys in the metformin group than in the insulin group (median 0.30 vs 0.75; p = 0.016). ConclusionsMaternal metformin treatment for GDM had no effects on adiposity, body composition, liver fat, or inflammation markers in prepubertal offspring compared to maternal insulin treatment but was associated with higher adiponectin concentration and lower leptin/adiponectin-ratio in boys.

Acute exercise affects dual-energy X-ray absorptiometry body composition estimates but not standardised ultrasound measurements of subcutaneous adipose tissue.

Ultrasound has been demonstrated to be a highly accurate and reliable tool for measuring subcutaneous adipose tissue thickness and is robust against changes in hydration status or acute food or fluid intake. However, the effect of prior acute exercise is unexamined. This study examined the impact of an acute endurance exercise and resistance exercise session on standardised brightness-mode ultrasound measurements of subcutaneous adipose tissue thickness compared to skinfolds and dual-energy X-ray absorptiometry body composition estimates. In a randomised cross-over design, 30 active adults (24.2 ± 4.9 years) undertook physique assessment via standardised brightness-mode ultrasound, skinfolds and dual-energy X-ray absorptiometry before, immediately and 45 min after an acute endurance or resistance exercise session. The mean sum of eight subcutaneous adipose tissue thickness measured via standardised brightness-mode ultrasound increased (0.6 mm, p = 0.04) immediately postendurance exercise but was not meaningful when evaluated against the technical error of measurement of the investigator. A significant (p = 0.01) but not meaningful decrease in the sum of eight skinfolds occurred immediately (-1.1 ± 0.4 mm) and 45 min (-1.3 ± 0.4 mm) postresistance exercise. Comparatively, endurance exercise elicited a meaningful decrease of total mass (460 ± 30 g) and trunk lean mass (680 ± 90 g) dual-energy X-ray absorptiometry estimates. Findings from this study indicate standardised client presentation may be unnecessary when employing either standardised brightness-mode ultrasound or skinfolds for body composition assessment unlike dual-energy X-ray absorptiometry.

Influence of sex hormones status and type of training on regional bone mineral density in exercising females

ABSTRACT The primary objective of this study was to examine the influence of hormonal ovarian profile and training characteristics on spine, pelvis, and total body bone mineral density (BMD) in a group of well-trained females. Forty-two eumenorrheic females, twenty-eight monophasic oral contraceptive (OC) users and thirteen postmenopausal females participated in this study. Body composition was measured by total body dual-energy X-ray absorptiometry (DXA) to determine BMD of the areas of interest. Endurance-trained premenopausal females showed lower spine BMD compared to resistance-trained premenopausal females (1.03 ± 0.1 vs. 1.09 ± 0.09 g/cm2; p = 0.025). Postmenopausal females reported lower BMD level in comparison to eumenorrheic females in pelvis (1.079 ± 0.082 vs 1.19 ± 0.115 g/cm2; p = 0.005), spine (0.969 ± 0.097 vs 1.069 ± 0.109 g/cm2; p = 0.012) and total (1.122 ± 0.08 vs 1.193 ± 0.077 g/cm2; p = 0.018) and OC users whose duration of OC use was less than 5 years (OC < 5) in pelvis (1.235 ± 0.068 g/cm2; p < 0.001) and spine (1.062 ± 0.069 g/cm2; p = 0.018). In addition, lower BMD values were found in OC users who had been using OC for more than 5 years (OC ≥ 5) than eumenorrheic females in pelvis (1.078 ± 0.086 g/cm2; p = 0.029) and spine (0.966 ± 0.08 g/cm2; p = 0.05). Likewise, OC ≥ 5 showed lower values than and OC < 5 in pelvis (p = 0.004) and spine (p = 0.047). We observed a lower spine BMD value in premenopausal endurance-trained females compared to premenopausal resistance-trained females. Moreover, this research observed that prolonged use of OCs may reduce bone mass acquisition in the spine and pelvis, even in well-trained females. Finally, postmenopausal showed lower BMD despite being exercising women. Trial registration: ClinicalTrials.gov identifier: NCT04458662. Highlights Ovarian hormonal profile should be considered when assessing BMD in female athletes. The duration of oral contraceptive use influences spine and pelvis regional BMD in exercising females. Postmenopausal women show lower BMD when compared to premenopausal females despite being exercising females.

The Significance of Dual-Energy X-ray Absorptiometry (DXA) Examination in Cushing's Syndrome-A Systematic Review.

In recent years, the usefulness of dual-energy X-ray absorptiometry (DXA) as a valuable complementary method of assessing the content and distribution of adipose and lean tissue as well as bone mineral density and estimating the risk of fractures has been increasingly confirmed. The diagnosis and treatment of Cushing's syndrome remain challenging, and monitoring the effects of treatment is often necessary. DXA tests offer a potential solution to many problems related to the availability of a quick, detailed, and reliable analysis of changes in the content and distribution of individual body composition components. The article discusses total body DXA scans (FMI, VAT, ALMI), lumbar spine scans (VFA, TBS), and osteoporosis scans (BMD, T-score, Z-score)-all are of potential interest in Cushing's syndrome. The article discusses the use of the most important indicators obtained from a DXA test (FMI, VAT, ALMI, BMD, T-score, Z-score, VFA, TBS) and their clinical significance in Cushing's syndrome was verified. The literature from the last decade was used for the study, available in MEDLINE, Web of Science, and ScienceDirect.

Predicting soft tissue thicknesses overlying the iliac crests and greater trochanters of younger and older adults.

Soft tissues overlying the hip play a critical role in protecting against fractures during fall-related hip impacts. Consequently, the development of an efficient and cost-effective method for estimating hip soft tissue thicknesses in living people may prove to be valuable for assessing an individual's injury risk and need to adopt preventative measures. The present study used multiple linear stepwise regression to generate prediction equations from participant characteristics (i.e., height, sex) and anthropometric measurements of the pelvis, trunk, and thigh to estimate soft tissue thickness at the iliac crests (IC) and greater trochanters (GT) in younger (16-35 years of age: 37 males, 37 females) and older (36-65 years of age: 38 males, 38 females) adults. Equations were validated against soft tissue thicknesses measured from full body Dual-energy X-ray Absorptiometry scans of independent samples (younger: 13 males, 13 females; older: 13 males, 12 females). Younger adult prediction equations exhibited adjusted R2 values ranging from 0.704 to 0.791, with more explained variance for soft tissue thicknesses at the GT than the IC; corresponding values for the older adult equations were higher overall and ranged from 0.819 to 0.852. Predicted and actual soft tissue thicknesses were significantly correlated for both the younger (R2 = 0.466 to 0.738) and older (R2 = 0.842 to 0.848) adults, averaging ≤ 0.75cm of error. This research demonstrates that soft tissue thicknesses overlying the GT and IC can be accurately predicted from equations using anthropometric measurements. These equations can be used by clinicians to identify individuals at higher risk of hip fractures who may benefit from the use of preventative measures.

Total and regional appendicular skeletal muscle mass prediction from dual-energy X-ray absorptiometry body composition models

Sarcopenia, sarcopenic obesity, frailty, and cachexia have in common skeletal muscle (SM) as a main component of their pathophysiology. The reference method for SM mass measurement is whole-body magnetic resonance imaging (MRI), although dual-energy X-ray absorptiometry (DXA) appendicular lean mass (ALM) serves as an affordable and practical SM surrogate. Empirical equations, developed on relatively small and diverse samples, are now used to predict total body SM from ALM and other covariates; prediction models for extremity SM mass are lacking. The aim of the current study was to develop and validate total body, arm, and leg SM mass prediction equations based on a large sample (N = 475) of adults evaluated with whole-body MRI and DXA for SM and ALM, respectively. Initial models were fit using ordinary least squares stepwise selection procedures; covariates beyond extremity lean mass made only small contributions to the final models that were developed using Deming regression. All three developed final models (total, arm, and leg) had high R2s (0.88–0.93; all p < 0.001) and small root-mean square errors (1.74, 0.41, and 0.95 kg) with no bias in the validation sample (N = 95). The new total body SM prediction model (SM = 1.12 × ALM – 0.63) showed good performance, with some bias, against previously reported DXA-ALM prediction models. These new total body and extremity SM prediction models, developed and validated in a large sample, afford an important and practical opportunity to evaluate SM mass in research and clinical settings.

Multicompartment body composition analysis in older adults: a cross-sectional study

BackgroundDuring aging, changes occur in the proportions of muscle, fat, and bone. Body composition (BC) alterations have a great impact on health, quality of life, and functional capacity. Several equations to predict BC using anthropometric measurements have been developed from a bi-compartmental (2-C) approach that determines only fat mass (FM) and fat-free mass (FFM). However, these models have several limitations, when considering constant density, progressive bone demineralization, and changes in the hydration of the FFM, as typical changes during senescence. Thus, the main purpose of this study was to propose and validate a new multi-compartmental anthropometric model to predict fat, bone, and musculature components in older adults of both sexes.MethodsThis cross-sectional study included 100 older adults of both sexes. To determine the dependent variables (fat mass [FM], bone mineral content [BMC], and appendicular lean soft tissue [ALST]) whole total and regional dual-energy X-rayabsorptiometry (DXA) body scans were performed. Twenty-nine anthropometric measures and sex were appointed as independent variables. Models were developed through multivariate linear regression. Finally, the predicted residual error sum of squares (PRESS) statistic was used to measure the effectiveness of the predicted value for each dependent variable.ResultsAn equation was developed to simultaneously predict FM, BMC, and ALST from only four variables: weight, half-arm span (HAS), triceps skinfold (TriSK), and sex. This model showed high coefficients of determination and low estimation errors (FM: R2adj: 0.83 and SEE: 3.16; BMC: R2adj: 0.61 and SEE: 0.30; ALST: R2adj: 0.85 and SEE: 1.65).ConclusionThe equations provide a reliable, practical, and low-cost instrument to monitor changes in body components during the aging process. The internal cross-validation method PRESS presented sufficient reliability in the model as an inexpensive alternative for clinical field use.

Sex differences in muscle SIRT1 and SIRT3 and exercise + weight loss effects on muscle sirtuins.

The sirtuins, SIRT1 and SIRT3, are involved in the control of cellular processes to maintain metabolic homeostasis. The purpose of this study was to determine the effects of a 6-month aerobic training + weight loss program and hyperinsulinemia on SIRT1 and SIRT3 expression in skeletal muscle and to compare their expression between men and women. Thirty-five adult men (n = 18) and postmenopausal women (n = 17), (X ± SEM, age: 61 ± 1 years, BMI: 31.3 ± 0.7 kg/m2) completed 6 months 3×/week of aerobic exercise and 1×/week dietary instruction to induce weight loss (EX + WL). Participants had a VO2max test, vastus lateralis muscle biopsies at baseline and 2 h into a hyperinsulinemic-euglycemic clamp, a total body dual-energy X-ray absorptiometry scan, and abdominal computed tomography scan. Skeletal muscle SIRT1, SIRT3, and PGC1-α mRNA expression were quantified by qRT-PCR. Skeletal muscle SIRT1 and SIRT3 mRNA expression are higher in women than men (P < 0.005). Body weight, body fat, and abdominal obesity decreased and VO2max and glucose utilization (M) increased after EX + WL (P < 0.001). Basal SIRT1 decreased following EX + WL (P < 0.05). This change in basal SIRT1 was not related to changes in VO2max, M or fat mass, nor was it different by gender. Insulin stimulation increased SIRT1 expression (P < 0.001) and PGC1-α expression (P < 0.01) following EX + WL (insulin-basal post). Sex differences in the levels of these sirtuins did not affect changes with EX + WL. Skeletal muscle SIRT1 decreases after a long-term combined exercise and weight loss program in middle-aged and older adults.

A comparison of associations of body mass index and dual-energy x-ray absorptiometry measured percentage fat and total fat with global serum metabolites in young women.

Body mass index (BMI) does not directly measure adiposity, whereas dual-energy x-ray absorptiometry (DXA) provides valid direct estimates of adiposity. Therefore, this study evaluated usefulness of BMI as a measure of adiposity in serum metabolomics studies. A cross-sectional analysis was conducted of 202 women aged 25 to 29 years in the Dietary Intervention Study in Children Follow-Up Study. Heights and weights were measured, and body composition was quantified using clinical DXA protocols. Serum metabolomic profiling was performed by liquid chromatography-tandem mass spectrometry. Partial correlations of BMI, percentage fat (%FAT), and total fat (TOTFAT) with log transformed serum metabolites were calculated. There was significant overlap in the 93 metabolites that correlated with BMI, %FAT, and/or TOTFAT; 9 differently correlated with BMI and %FAT, whereas 15differently correlated with BMI and TOTFAT. Even for these metabolites, absolute differences were modest. Metabolite set enrichment analysis identified diacylglycerol and sphingolipid metabolism as overrepresented among metabolites significantly correlated with all three measures of adiposity. BMI can be a good proxy for DXA measured %FAT and TOTFAT in descriptive metabolomic studies of healthy, young White women. Larger studies in more diverse populations are needed to endorse more generalized conclusions.