Dual-energy X-ray Absorptiometry Measurements Research Articles

End-to-End Semi-Supervised Opportunistic Osteoporosis Screening Using Computed Tomography.

Osteoporosis is the most common metabolic bone disease and can cause fragility fractures. Despite this, screening utilization rates for osteoporosis remain low among populations at risk. Automated bone mineral density (BMD) estimation using computed tomography (CT) can help bridge this gap and serve as an alternative screening method to dual-energy X-ray absorptiometry (DXA). The feasibility of an opportunistic and population agnostic screening method for osteoporosis using abdominal CT scans without bone densitometry phantom-based calibration was investigated in this retrospective study. A total of 268 abdominal CT-DXA pairs and 99 abdominal CT studies without DXA scores were obtained from an oncology specialty clinic in the Republic of Korea. The center axial CT slices from the L1, L2, L3, and L4 lumbar vertebrae were annotated with the CT slice level and spine segmentation labels for each subject. Deep learning models were trained to localize the center axial slice from the CT scan of the torso, segment the vertebral bone, and estimate BMD for the top four lumbar vertebrae. Automated vertebra-level DXA measurements showed a mean absolute error (MAE) of 0.079, Pearson's r of 0.852 (P<0.001), and R2 of 0.714. Subject-level predictions on the held-out test set had a MAE of 0.066, Pearson's r of 0.907 (P<0.001), and R2 of 0.781. CT scans collected during routine examinations without bone densitometry calibration can be used to generate DXA BMD predictions.

Association of serum sclerostin levels with marrow adiposity in postmenopausal women with glucocorticoid-induced osteoporosis

BackgroundGlucocorticoids and sclerostin act as inhibitors of the Wnt signaling pathway, thereby hindering bone formation. Given the pathway's intricate association with mesenchymal stem cells, the hypothesis suggests that heightened sclerostin levels may be intricately linked to an augmentation in marrow adiposity induced by glucocorticoids. This study endeavored to delve into the nuanced relationship between circulating sclerostin and bone marrow adipose tissue in postmenopausal women grappling with glucocorticoid-induced osteoporosis (GIO).MethodsIn this cross-sectional study, 103 patients with autoimmune-associated diseases underwent glucocorticoid treatment, boasting an average age of 61.3 years (standard deviation 7.1 years). The investigation encompassed a thorough assessment, incorporating medical history, anthropometric data, biochemical analysis, and dual-energy X-ray absorptiometry measurements of lumbar and femoral bone mineral density (BMD). Osteoporosis criteria were established at a T-score of -2.5 or lower. Additionally, MR spectroscopy quantified the vertebral marrow fat fraction.ResultsBMD at the femoral neck, total hip, and lumbar spine showcased an inverse correlation with marrow fat fraction (r = –0.511 to – 0.647, P < 0.001). Serum sclerostin levels exhibited a positive correlation with BMD at various skeletal sites (r = 0.476 to 0.589, P < 0.001). A noteworthy correlation emerged between circulating sclerostin and marrow fat fraction at the lumbar spine (r = –0.731, 95% CI, –0.810 to –0.627, P < 0.001). Multivariate analysis brought to light that vertebral marrow fat fraction significantly contributed to sclerostin serum concentrations (standardized regression coefficient ß = 0.462, P < 0.001). Even after adjusting for age, body mass index, physical activity, renal function, BMD, and the duration and doses of glucocorticoid treatment, serum sclerostin levels maintained a significant correlation with marrow fat fraction.ConclusionsCirculating sclerostin levels exhibited a noteworthy association with marrow adiposity in postmenopausal women grappling with GIO.

Reliability and Agreement Assessment of Sarcopenia Diagnosis through Comparison of Bioelectrical Impedance Analysis and Dual-Energy X-ray Absorptiometry.

A unified diagnostic criterion has yet to be established for sarcopenia. Therefore, we analyzed the reliability and validity of sarcopenia diagnosis using bioelectrical impedance analysis (BIA) compared with the gold standard, dual-energy X-ray absorptiometry (DEXA), and evaluated the predictive accuracy of BIA for diagnosis. The clinical trial, involving a total of 239 participants, was conducted between December 2018 and September 2019 on healthy volunteers without significant medical histories. The participants underwent health assessments, followed by sequential DEXA and BIA measurements. In both the low and normal appendicular skeletal muscle (ASM) groups, there were significant differences in the right arm, left arm, right leg, left leg, ASM, and ASM index (ASMI) between DEXA and BIA across all age groups (p < 0.05). BIA tended to overestimate compared to DEXA, but ASMI values for males and females were consistent with the criteria for sarcopenia. Bland-Altman analysis showed that each segment in both the low and normal ASM groups fell within the limits of agreement (LOA). The diagnosis of sarcopenia using BIA was significantly different from that using DEXA. However, it exhibited a significantly high correlation, fell within the LOA, and demonstrated high predictive accuracy. BIA can be considered an effective tool for diagnosing sarcopenia.

Off- to in-season body composition adaptations in elite male and female endurance and power event athletics competitors: an observational study

BackgroundMonitoring elite athletes’ body composition (BC) is vital for health and optimizing performance in sports emphasizing leanness, such as athletics. This study aims to investigate and compare sex- and event-specific off-to in-season BC changes in endurance and power event athletics competitors.MethodsElite male and female endurance athletes (> 800 m runners; n = 21) and power event athletes (sprinters, jumpers; n = 32) underwent dual-energy X-ray absorptiometry (DXA) scans for whole and regional lean mass (LM), fat mass (FM), bone mineral content (BMC), and density (BMD) during off-season (September-October) and in-season (April-May). Linear mixed models tested between-group off-season differences in BC, within-group off-season to in-season changes, and between-group differences in change. To assess meaningful or least significant changes (LSC) in BC, DXA precision errors were determined from two consecutive total body scans in a subsample of athletes (n = 30).ResultsMale athletes (n = 26) gained significantly (p < 0.05) more body mass (BM; mean difference 1.5 [95% confidence interval (CI):0.5–2.4] kg), LM (843 [95% CI:-253:1459] g), and trunk LM (756 [-502:1156] g) than female athletes (n = 27). The proportion of changes in athlete’s BC exceeding the LSC threshold for LM and trunk LM were 70% and 65% in males, and 48% and 26% in females. Significant (p < 0.05) within-group off-season to in-season increases in LM were found for male endurance and power athletes, and female power athletes. All groups significantly increased BMD (p < 0.05). Only male and female power athletes had significant in- to-off-season increases in BMC. 80% of all athletes who had a meaningful increase in BMC belonged to the power event group. No significant within- or between group change in FM was observed.ConclusionsThe present study found that male athletes gained more BM, LM and trunk LM than females. Within-group increases in regional and whole-body LM and BMC were predominantly found among power event competitors. Incorporating individual meaningful changes alongside traditional statistics provided additional insights into sex and event-group differences. Future research on elite athletic event groups should include DXA measurements closer to major outdoor-season competitions, coupled with site-specific measures (ultrasound, MRI) for better detection of subtle changes in LM and FM.

Running Event, Age, and Competitive Level as Predictors of Dual-Energy X-Ray Absorptiometry-Derived Body Composition and Bone Health Markers in Female Runners.

Wilson, LJ and Curtis, C. Running event, age, and competitive level as predictors of dual-energy x-ray absorptiometry-derived body composition and bone health markers in female runners. J Strength Cond Res XX(X): 000-000, 2024-The aim of this study was to assess the impact of running discipline, competitive level (COMP), and age on body composition measures in female athletes. A total of n = 51 female runners (age: 30.9 ± 5.7 years, stature: 166.7 ± 5.7 cm, and body mass (BM): 57.1 ± 8.2 kg) completed a full-body dual-energy x-ray absorptiometry (DXA) scan in a cross-sectional design. One-way ANOVA or Kruskal-Wallis was used to identify differences in DXA measures and independent variables. Stepwise regression determined the contribution of independent variables on DXA measures. Body fat percentage (BF%) and fat mass (FM) differed based on COMP (BF%: H(2) = 17.451; FM: H(2) = 17.406, both p ≤ 0.0001). Competitive level modestly predicted BF% and FM (BF%: R2adj = 0.316, F(1,50) = 22.660; FM: R2adj = 0.300, F(1,50) = 21.029, both p ≤ 0.0001). Bone mineral density (BMD) and BMD Z-score (BMDZ) did not differ between age, running discipline, or COMP (age: BMD: F(2,50) = 2.825, BMDZ: F(2,50) = 2.215; running discipline: BMD: F(3,50) = 1.145, BMDZ: F(3,50) = 1.474; COMP: BMD: F(2,50) = 0.074, BMDZ: F(2,50) = 1.297, all p ≤ 0.05). Age and running discipline modestly predicted BMD and BMDZ (BMD: R2adj = 0.179, F(1,50) = 5.264; BMDZ: R2adj = 0.173, F(1,50) = 4.545, both p ≤ 0.05). These findings indicate COMP may be a predictor of BF% and FM. Age and running discipline appear predictors of bone health markers. Such findings may enable medical and sport science practitioners to tailor interventions relating to realization of training adaptations, performance, and health.

Title: Sarcopenia assessed by DXA and hand-grip dynamometer: a potential marker of damage, disability and myokines imbalance in inflammatory myopathies.

To assess the ability of dual-energy X-ray absorptiometry (DXA) and hand-grip dynamometer to measure damage in inflammatory myopathies (IM). . Forty adult IM patients with a disease duration ≥12 months, low or no disease activity for ≥6 months, were prospectively enrolled. Thirty healthy age and sex-matched volunteers were enrolled as controls. Whole-body DXA and hand-grip dynamometer were used to measure muscle mass, grip strength and diagnose sarcopenia (EWGSOP2 criteria). Relationships between the results of strength in 12 muscles, functional tests, patient-reported disability, IMACS damage score, and history of the disease were assessed. The serum levels of potential molecular actors of the damage were measured. DXA and grip strength measurements took ≤20 min. Both muscle mass and grip strength were decreased in IM patients vs volunteers (-10% and -30% respectively) with a dispersion that varied widely (IQR -24.3% to + 7.8% and -51.3% to -18.9% respectively). Muscle mass and grip strength were non-redundantly correlated (r up to 0.6, p= 0.0001) with strength in 14 muscles (manual muscle test and hand-held dynamometer), functions (of limbs, respiratory and deglutition muscles), patient-reported disability, damage (extension and severity in muscular and extra-muscular domains), and blood-levels of several myokines. Seven IM patients (17.5%) were sarcopenic. They had the worst damage, functions impairment, disability and history of severe myopathy. Decreased irisin and osteonectin levels were associated with sarcopenia (AUC 0.71 and 0.80, respectively). DXA and hand-grip dynamometer are useful tools to assess damage in IM. Irisin and osteonectin may play a role in IM damage pathogenesis.

The distribution of breast density in women aged 18years and older.

Age and body mass index (BMI) are critical considerations when assessing individual breast cancer risk, particularly for women with dense breasts. However, age- and BMI-standardized estimates of breast density are not available for screen-aged women, and little is known about the distribution of breast density in women aged < 40. This cross-sectional study uses three different modalities: optical breast spectroscopy (OBS), dual-energy X-ray absorptiometry (DXA), and mammography, to describe the distributions of breast density across categories of age and BMI. Breast density measures were estimated for 1,961 Australian women aged 18-97years using OBS (%water and %water + %collagen). Of these, 935 women had DXA measures (percent and absolute fibroglandular dense volume, %FGV and FGV, respectively) and 354 had conventional mammographic measures (percent and absolute dense area). The distributions for each breast density measure were described across categories of age and BMI. The mean age was 38years (standard deviation = 15). Median breast density measures decreased with age and BMI for all three modalities, except for DXA-FGV, which increased with BMI and decreased after age 30. The variation in breast density measures was largest for younger women and decreased with increasing age and BMI. This unique study describes the distribution of breast density measures for women aged 18-97 using alternative and conventional modalities of measurement. While this study is the largest of its kind, larger sample sizes are needed to provide clinically useful age-standardized measures to identify women with high breast density for their age or BMI.

Fat and fat-free mass measurement agreement by dual-energy X-ray absorptiometry versus bioelectrical impedance analysis: Effects of posture and waist circumference.

Bioelectrical impedance analysis (BIA) operates under the assumption that the conductor has a uniform cylindrical shape. However, this assumption may be violated if measures are taken in the seated position, especially in people with a high waist circumference (WC). The aims of this research were to determine whether posture (supine, standing, and seated) and WC affect agreement between BIA and dual-energy X-ray absorptiometry (DXA) measures of fat mass (FM) and fat-free mass (FFM). Baseline data were collected from 28 adults (mean=61.4±6.9years, 64.3% female) with obesity (BMI 38.6±5.0kg/m2). Body composition was measured using BIA in the supine, standing, and seated positions and by DXA while supine. Intraclass correlation coefficient (ICC) analyses with two-way mixed effects and absolute agreement were performed to determine agreement. Point estimates were excellent for FM and FFM while supine, excellent for FM and good for FFM while standing, and moderate for FM and good for FFM while seated. BIA measures in the supine position resulted in the narrowest 95% confidence intervals compared with other positions. Better agreement was observed across all positions in participants with a WC below the median (118.3cm). Despite the potential pragmatic value of measuring with BIA in a seated position, the results of this analysis demonstrate the poorest agreement between DXA and BIA methods, especially in individuals with high WC. Findings from this study demonstrate that BIA, particularly when measured in a supine position, can serve as a viable alternative to DXA for measuring body composition in people with obesity.

The associations of "weekend warrior" and regularly active physical activity with abdominal and general adiposity in US adults.

This study examined the association between physical activity patterns and abdominal and general adiposity. Data were extracted among 20- to 59-year-old participants in the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018. Abdominal and general adiposity was assessed by dual-energy x-ray absorptiometry (DXA) and anthropometric measures. DXA-measured indicators were further normalized into z scores. Physical activity levels were collected by questionnaire and classified as inactive, "weekend warrior" (WW), and regularly active (RA). Survey linear regression models were used to assess associations between physical activity patterns and adiposity indicators. Among 9629 participants, 772 (8.2%) reported the WW pattern and 3277 (36.9%) reported the RA pattern. Compared with inactive, both WW and RA had lower DXA-measured abdominal adiposity (WW: β: -0.24, 95% CI: -0.38 to -0.10; RA: -0.18, 95% CI: -0.29 to -0.07), waist circumference (WW: β: -1.94, 95% CI: -3.16 to -0.73; RA: -1.31, 95% CI: -2.32 to -0.29), whole-body fat mass (WW: β: -0.16, 95% CI: -0.25 to -0.08; RA: -0.11, 95% CI: -0.18 to -0.04), and BMI (WW: β: -0.78, 95% CI: -1.27 to -0.28; RA: -0.47, 95% CI: -0.89 to -0.04). The WW pattern was associated with similarly lower abdominal and general adiposity to the RA pattern versus the inactive pattern.

DEXA-based Fat Mass with the Risk of Worsening Insulin Resistance in Adolescents: A 9-Year Temporal and Mediation Study.

Surrogate measures of childhood and adolescent obesity have impaired the understanding of body composition's relationship with insulin resistance in the young population. We aim to examine the longitudinal associations of directly measured total fat mass, trunk fat mass, and lean mass with the risk of hyperglycaemia, hyperinsulinemia, and insulin resistance from ages 15-24 years, the mediation path through which lipids and inflammation influence insulin resistance and whether increased fat mass temporally precede insulin resistance. We studied 3160 adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC), UK birth cohort, who had complete dual-energy Xray absorptiometry measure and fasting blood samples at age 15 years and repeated measures at ages 17- and 24-years clinic visit. Fasting glucose >6.1 mmol/L, insulin >11.78 mU/L, and homeostatic model assessment for insulin resistance (HOMA-IR) ≥75th percentile were categorized as hyperglycaemia, hyperinsulinemia, and high insulin resistance, respectively. Longitudinal associations were examined with generalized logit-mixed effect models, whilst mediation and temporal path analyses were examined using structural equation models, adjusting for cardiometabolic and other lifestyle factors. Among 3160 participants (51% female), fat mass and lean mass increased linearly in both males and females while glucose, insulin, and HOMA-IR had a U-shaped course from age 15 through 24 years. After full adjustment, each 1 kg cumulative increase in total fat mass [odds ratio 1.12 (95% confidence interval 1.11-1.13)] and trunk fat mass [1.21 (1.19-1.23)] from ages 15 through 24 years were associated with a progressively worsening risk of high insulin resistance as well as hyperglycaemia and hyperinsulinemia. The association of increased total fat mass with increased insulin resistance was partly mediated by triglycerides (9% mediation). In the temporal path analysis, higher total fat mass at age 15 years was associated with higher insulin resistance at 17 years, but not vice versa. Higher total fat mass at 17 years was bi-directionally associated with higher insulin resistance at 24 years. Mid-adolescence may be an optimal time for interrupting the worsening fat mass-insulin resistance pathologic cycle and attenuating the risk of progressively worsening metabolic dysfunction before young adulthood.

Validation of dual energy X-ray absorptiometry for longitudinal quantification of tumor burden in a murine model of pancreatic ductal adenocarcinoma.

Noninvasive imaging is central to preclinical, in vivo models of pancreatic ductal adenocarcinoma (PDAC). While bioluminescent imaging (BLI) is a gold standard, its signal is dependent on the metabolic activity of tumor cells. In contrast, dual energy X-ray absorptiometry (DEXA) is a direct measure of body composition. Thus, we aimed to assess its potential for longitudinal quantification of tumor burden versus BLI. We utilized the KCKO murine model of PDAC and subjected tumor-bearing (n = 20) and non-tumor control (NTC) (n = 10) animals to weekly BLI and DEXA measurements for up to 10 weeks. While BLI detected tumors at 1-week, it failed to detect tumor growth, displayed a decreasing trend overtime (slope = -9.0x108; p = 0.0028), and terminal signal did not correlate with ex vivo tumor mass (r = 0.01853; p = 0.6286). In contrast, DEXA did not detect elevated changes in abdominal cavity lean mass until week 2 post inoculation and tumors were not visible until week 3, but successfully quantified a tumor growth trend (slope = 0.7322; p<0.0001), and strongly correlated with final tumor mass (r = 0.9351; p<0.0001). These findings support the use of BLI for initial tumor engraftment and persistence but demonstrate the superiority of DEXA for longitudinal tumor burden studies. As tumor detection by DEXA is not restricted to luciferase expressing models, future studies to assess its value in various cancer models and as an in vivo outcome measure of treatment efficacy are warranted.

Problematic video gaming is negatively associated with bone mineral density in adolescents.

Adolescent bone health may be negatively impacted by problematic video gaming (PVG) due to factors such as prolonged screen time, poor sleep quality, and increased depression. Although sedentary behaviors have been linked to decreased bone mass, there is limited research on how PVG impacts bone health. We aimed to evaluate the association between PVG and bone mineral density (BMD) in adolescents by comparing the BMD z-scores of adolescents with and without PVG and by identifying PVG-related risk factors that may affect low BMD scores. This cross-sectional study took place between May 2019 and August 2021 with 110 adolescents who played video games for at least two hours per day. Data on screen time, game genre, tobacco, alcohol, caffeine consumption, and vigorous physical activity status were recorded. PVG was assessed using the Internet Gaming Disorder-Short Form (IGDS9-SF), with scores ≤ 16 comprising the control group and > 16 the PVG group. Sleep quality was assessed by Pittsburgh Sleep Quality Index, and depression was evaluated by Children's Depression Inventory. Dual-energy X-ray absorptiometry measurements of femoral neck and lumbar spine BMD were compared between the two groups. The mean age of the participants was 14.2 ± 1.8years, and 86.4% were males. The PVG group exhibited lower femoral neck z-scores (p = 0.013) and a higher proportion of adolescents with low femoral neck BMD risk (27.8% vs 9.7%, p = 0.041). Lumber spine z-scores did not differ (p = 0.271). Despite poorer depressive symptoms and sleep quality in the PVG group, they were not associated with low BMD risk (OR 1.02, 95% CI 0.97-1.08, p = 0.398 and OR 1.00, 95% CI 0.87-1.18, p = 0.972, respectively). Among all PVG-related risk factors, video game time (aOR = 1.22, 95% CI = 1.06-1.41, p = 0.006) and vigorous physical activity amount (aOR = 2.86, 95% CI = 0.93-8.76, p = 0.080) showed the strongest associations with femoral neck z-scores. Conclusion: The results of this study, showing a negative association between PVG and femoral neck BMD in adolescents, underscore the importance evaluating, monitoring, and supporting lower extremity bone health in adolescents with PVG. What is Known: • Adolescents with problematic video gaming are at risk for depression, impaired sleep; sedentary lifestyle; consumption of tobacco, alcohol, and drugs; and high caffeine intake. • These risk factors might lead to compromised bone health. What is New: • Problematic video gaming is associated with the low femoral neck bone mineral density risk in adolescents. • Extended video game time and reduced physical activity are found to be the primary risk factors.

Validity of bioelectric impedance analysis for body composition assessment in interstitial lung disease patients.

changes in body composition (BC) are common in interstitial lung disease, which leads to an increased risk of complications and infections, and are associated with poor quality of life and worse outcomes. BC assessment is important to identify malnutrition and sarcopenia. However, gold-standard techniques are not available in all clinical settings. this study aimed to evaluate the agreement and reliability of body composition estimated by bioelectric impedance analysis (BIA) and measured using dual-energy x-ray absorptiometry (DEXA) in women with interstitial lung disease. this is a cross-sectional study. BC (fat mass and appendicular skeletal muscle mass) were assessed using BIA multifrequency and DEXA in standardized conditions. Agreement and reliability between techniques were evaluated using Bland-Altman plots and the intraclass correlation coefficient (ICC). a total of 50 women were evaluated. No differences were observed for FM (BIA, 25.8 ± 10.2 kg and DEXA, 26.3 ± 10.0 kg, p = 0.77) and ASMM (BIA, 14.1 ± 2.7 kg and DEXA, 13.9 ± 2.3 kg, p = 0.83). Based on ICC, good reliability was observed for FM (ICC, 0.98) and ASMM (ICC, 0.93). BC estimated by BIA showed good agreement and reliability with DEXA measurements. In the absence of this method, BIA can replace the DEXA technique for body composition assessment.

Evaluation of Multi-Frequency Bioelectrical Impedance Analysis against Dual-Energy X-ray Absorptiometry for Estimation of Low Muscle Mass in Older Hospitalized Patients.

The accuracy of multi-frequency (MF) bioelectrical impedance analysis (BIA) to estimate low muscle mass in older hospitalized patients remains unclear. This study aimed to describe the ability of MF-BIA to identify low muscle mass as proposed by The Global Leadership Initiative on Malnutrition (GLIM) and The European Working Group on Sarcopenia in Older People (EWGSOP-2) and examine the association between muscle mass, dehydration, malnutrition, and poor appetite in older hospitalized patients. In this prospective exploratory cohort study, low muscle mass was estimated with MF-BIA against dual-energy X-ray absorptiometry (DXA) in 42 older hospitalized adults (≥65 years). The primary variable for muscle mass was appendicular skeletal muscle mass (ASM), and secondary variables were appendicular skeletal muscle mass index (ASMI) and fat-free mass index (FFMI). Cut-off values for low muscle mass were based on recommendations by GLIM and EWGSOP-2. MF-BIA was evaluated against DXA on the ability to estimate absolute values of muscle mass by mean bias, limits of agreement (LOA), and accuracy (5% and 10% levels). Agreement between MF-BIA and DXA to identify low muscle mass was evaluated with sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV). The association between muscle mass, dehydration, malnutrition, and poor appetite was visually examined with boxplots. MF-BIA overestimated absolute values of ASM with a mean bias of 0.63 kg (CI: -0.20:1.46, LOA: -4.61:5.87). Agreement between MF-BIA and DXA measures of ASM showed a sensitivity of 86%, specificity of 94%, PPV of 75% and NPV of 97%. Boxplots indicate that ASM is lower in patients with malnutrition. This was not observed in patients with poor appetite. We observed a tendency toward higher ASM in patients with dehydration. Estimation of absolute ASM values with MF-BIA should be interpreted with caution, but MF-BIA might identify low muscle mass in older hospitalized patients.

Radiofrequency Echographic Multispectrometry (REMS) can Overcome the Effects of Structural Internal Artifacts and Evaluate Bone Fragility Accurately.

This study measured bone mineral density (BMD) in a Japanese population using the novel non-ionizing system using radiofrequency echographic multispectrometry (REMS) and compared the results with those obtained using traditional dual-energy X-ray absorptiometry (DXA). We aimed to identify any discrepancies between measurements obtained using these instruments and identify the influencing factors. This cross-sectional study examined patients with osteoporosis treated at a single center from April to August 2023. We examined BMD assessment by DXA and REMS in lumbar spine and proximal femur. Patients were categorized into two groups: those with discrepancies between lumbar spine BMD measured by DXA and REMS, and those without. Semiquantitative evaluation of vertebral fractures and abdominal aortic calcification scoring were also performed and compared between the two groups, along with various patient characteristics. A total of 70 patients (88.6% female; mean age 78.39 ± 9.50years) undergoing osteoporosis treatment were included in the study. A significant difference was noted between DXA and REMS measurement of BMD and T-scores, with REMS recording consistently lower values. The discrepancy group exhibited a higher incidence of multiple vertebral fractures and increased vascular calcification than the non-discrepancy group. Multivariate analysis indicated that diabetes mellitus, severe vertebral fractures, and increased abdominal aortic calcification scores were significantly associated with discrepancies in lumbar spine T-scores. This study suggests that REMS may offer a more accurate measurement of BMD, overcoming the overestimation of BMD by DXA owing to factors such as vertebral deformities, abdominal aortic calcification, and diabetes mellitus.

The effect of femur positioning on dual-energy X-ray absorptiometry (DXA) measures and statistical shape and appearance modeling (SSAM) fracture risk assessments.

The diagnosis of osteoporosis using Dual-energy X-ray Absorptiometry (DXA) relies on accurate hip scans, whereby variability in measurements may be introduced by altered patient positioning, as could occur with repeated scans over time. The goal herein was to test how altered postures affect diagnostic metrics (i.e., standard clinical metrics and a newer image processing tool) for femur positioning. A device was built to support cadaveric femurs and adjust their orientation in 3° increments in flexion and internal/external rotation. Seven isolated femurs were scanned in six flexion postures (0° (neutral) to 15° of flexion) and eleven rotational postures (15° external to 15° internal rotation) while collecting standard clinical DXA-based measures for each scan. The fracture risk tool was applied to each scan to calculate fracture risk. Two separate one-way repeated measures ANOVAs (α = 0.05) were performed on the DXA-based measures and fracture risk prediction output. Flexion had a significant effect on T-score, Bone Mineral Density (BMD), and Bone Mineral Content (BMC), but not area, at angles greater than 12°. Internal and external rotation did not have a significant effect on any clinical metric. Fracture risk (as assessed by the image processing tool) was not affected by either rotation mode. Overall, this suggests clinicians can adjust patient posture to accommodate discomfort if deviations are less than 12 degrees, and the greatest care should be taken in flexion. Furthermore, the tool is relatively insensitive to postural adjustments, and as such may be a good option for tracking risk over repeated patient scans.

The Effect of a Compression Bandage on Dual Energy X-ray Absorptiometry Body Composition Scores

Background: Dual-energy X-ray absorptiometry (DXA) measures are affected by the noise produced by external factors such as textile compression found in loose clothing. The study aimed to determine the effect of a compression bandage (CB) on body composition (BC) assessed by DXA.Methods: Sixty volunteers (age=21.4±4.7yr.) underwent full-body DXA scans on a control (CTRL) condition and after wearing a 30-mmHg CB on the trunk, legs, and arms. ANOVA (2 genders by 2 experimental conditions) determined mean interactions in BC variables tissue body fat% (BF%), region body fat% (RBF%), body tissue (BT), fat mass (FM), lean mass (LM), bone mineral content (BMC), and total mass (TM). Absolute reliability in BC scores was studied by the typical error of the measurement (TEM), the coefficient of variability (CV), and Bland-Altman plots.Results: ANOVA interactions were found on tissue total BF% (p=0.049), RBF% (p=0.048), android lean mass (p=0.004), and android total mass (p=0.019). The CV was small for tissue BF% (2.61±0.93%, CI95%=0.79, 4.43%), RBF% (2.66±1.78%, CI95%=-0.83, 6.15%), BT (4.82±2.19%, CI95%=0.54, 9.10kg), FM (4.17±2.25%, CI95%=-0.24, 8.58kg), LM (3.25±2.44%, CI95%=-1.53, 8.04kg), BMC (4.81±2.96%, CI95%=-0.99, 10.62kg), and TM (2.84±2.80%, CI95%=-2.65, 8.33kg). Bland-Altman plots showed random error for BF%, LM, and BMC. A bias of 0.5% was observed on BF% in males.Conclusion: A CB worn during a full-body DXA scan elicited similar BC scores than not wearing it. The variation in scores was <10% for most BC variables, and a trivial bias of 0.5% in BF% was detected in male scores.

Comparative Analysis of CT Texture in Lumbar and Femur and Its Correlation with Bone Mineral Density and Content over Time: An Exploratory Study

Background: This research explores the application of morphometric texture analysis in chest Computed Tomography (CT) scans for determining Bone Mineral Content (BMC) and its temporal changes, both crucial in diagnosing osteoporosis. The study establishes an innovative approach to osteoporosis screening by leveraging Hounsfield Units (HUs) in CT scans to evaluate BMC, offering a comparison with dual-energy X-ray absorptiometry (DXA)-based BMC. Methods: A total of 806 instances (encompassing 379 individuals) were meticulously compiled from a sole institution, during the period stretching from 6 May 2012 to 30 June 2020. In this detailed analysis, each participant was subjected to a pair of chest CT scans, sequentially pursued by a DXA scan, spread over two years. Focused records of BMC values at the inaugural lumbar vertebra (L1) were secured from both the DXA and CT axial slices across all instances. A meticulous selection process pinpointed the largest trabecular section from the L1 vertebral body, whereupon 45 distinctive texture attributes were harvested utilizing gray-level co-occurrence matrix methodologies. Utilizing these amassed 45 attributes, a regression architecture was devised, aiming to forecast the precise BMC values individually. Moreover, an alternative regression framework was engaged, leveraging 90 distinct features, to gauge the BMC fluctuations observed between the duo of scans administered to each participant. Results: The precision of the cultivated regression frameworks was scrupulously assessed, benchmarking against the correlation coefficient (CC) and the mean absolute deviation (MAE) in comparison to the DXA-established references. The regression apparatus employed for estimating BMC unveiled a CC of 0.754 and an MAE of 1.641 (g), respectively. Conversely, the regression mechanism devoted to discerning the variations in BMC manifested a CC of 0.680, coupled with an MAE of 0.528 (g), respectively. Conclusion: The innovative methodology utilizing morphometric texture analysis in CT HUs offers an indirect, yet promising, approach for osteoporosis screening by providing estimations of BMC and its temporal changes. The estimations demonstrate moderate positive correlations with DXA measures, suggesting a potential alternative in circumstances where DXA scanning is limited.

Relationship between quadriceps muscle computed tomography measurement and motor function, muscle mass, and sarcopenia diagnosis.

The quadriceps muscle is one of the human body's largest and most clinically important muscles and is evaluated using mid-thigh computed tomography (CT); however, its relationship with motor function and sarcopenia remains unclear. Herein, we investigated the relationship between the cross-sectional area (CSA) of the quadriceps muscle, CT attenuation value (CTV), dual-energy X-ray absorptiometry muscle mass measurements, and muscle strength and motor function to evaluate the relationship between muscle mass loss and motor function decline, determine the diagnostic ability for sarcopenia, and confirm the usefulness of quadriceps muscle CT evaluation. A total of 472 middle-aged and older community dwellers (254 men and 218 women) aged ≥40 years (mean age: 62.3 years) were included in this study. The quantity and quality of the quadriceps muscle were assessed using CSA and CTV (CSA×CTV) as a composite index multiplied by quality and quantity. Age-adjusted partial correlations by sex with eight motor functions (knee extension muscle strength, power, normal walking speed, fast walking speed, grip strength, sit-up ability, balance ability, and reaction time) were evaluated, including correction methods for height, weight, and body mass index (BMI). Further, the accuracy of sarcopenia diagnosis was evaluated using appendicular muscle mass with dual-energy X-ray absorptiometry measurements, grip strength, and walking speed as the gold standard, and receiver operating characteristic curves were plotted to evaluate diagnostic performance. In men, CSA and CSA×CTV were significantly associated with seven of the eight motor functions (p<0.05), excluding only balance ability. BMI-corrected CSA was significantly correlated with all eight motor functions in men and women (p<0.05). In the diagnosis of sarcopenia based on skeletal muscle index, CSA (area under the curve (AUC) 0.935) and CSA×CTV (AUC 0.936) and their correction by height (CSA/height (AUC 0.917) and CSA×CTV/height (AUC 0.920)) were highly accurate and useful for diagnosis in men but moderately accurate in women (CSA (AUC 0.809), CSA×CTV (AUC 0.824), CSA/height (AUC 0.799), CSA×CTV/height (AUC 0.814)). The present results showed that a single CT image of the quadriceps muscle at the mid-thigh is useful for diagnosing sarcopenic changes, such as loss of muscle mass, muscle weakness, and muscle function.

Body composition in adults born preterm with very low birth weight

BackgroundStudies on body composition in preterm very low birth weight (VLBW < 1500 g) survivors are inconsistent and trajectories later in life unknown. We assessed body composition and its change from young to mid-adulthood in VLBW adults.MethodsWe studied 137 VLBW adults and 158 term-born controls from two birth cohorts in Finland and Norway at mean age 36 years. Body composition was assessed by 8-polar bioelectrical impedance. We compared results with dual-energy x-ray absorptiometry measurements at 24 years.ResultsIn mid-adulthood, VLBW women and men were shorter than controls. Fat percentage (mean difference in women 1.1%; 95% CI, –1.5% to 3.5%, men 0.8%; –2.0% to 3.6%) and BMI were similar. VLBW women had 2.9 (0.9 to 4.8) kg and VLBW men 5.3 (2.7 to 8.1) kg lower lean body mass than controls, mostly attributable to shorter height. Between young and mid-adulthood, both groups gained fat and lean body mass (p for interaction VLBW x age>0.3).ConclusionCompared with term-born controls, VLBW adults had similar body fat percentage but lower lean body mass, largely explained by their shorter height. This could contribute to lower insulin sensitivity and muscular fitness previously found in VLBW survivors and predispose to functional limitations with increasing age.ImpactIn mid-adulthood, individuals born preterm with very low birth weight had similar body fat percentage but lower lean body mass than those born at term. This was largely explained by their shorter height.First study to report longitudinal assessments of body size and composition from young to mid-adulthood in very low birth weight adults.Lower lean body mass in very low birth weight adults could contribute to lower insulin sensitivity and muscular fitness and lead to earlier functional limitations with increasing age.