Dual-energy X-ray Absorptiometry Research Articles

Agreement between fat-free mass from bioelectrical impedance analysis and dual-energy X-ray absorptiometry and their use in estimating resting metabolic rate in resistance-trained men.

This study aimed to determine the agreement between fat-free mass (FFM) estimates from bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA) and their use in estimating resting metabolic rate (RMR) in men undergoing resistance training. Thirty healthy resistance-trained men (22.7 ± 4.4 years, 70.0 ± 8.7 kg, 174.6 ± 6.7 cm, and 22.9 ± 2.3 kg/m2) were evaluated. The equation developed by Tinsley et al. (RMR = 25.9 × fat-free mass [FFM] + 284) was adopted to calculate the RMR. DXA was used as the reference method for FFM. Furthermore, FFM was also estimated by BIA using a spectral device. No significant difference (p > 0.05) was observed between DXA (1884.2 ± 145.5 kcal) and BIA (1849.4 ± 167.7 kcal) to estimate RMR. A positive and significant correlation (r = 0.89, p < 0.05) was observed between DXA and BIA estimates of RMR. The mean difference between methods indicated that BIA presented a bias of -34.8 kcal. These findings suggest that using FFM derived from DXA or BIA results in similar RMR estimates in resistance-trained men.

Trabecular bone score norms in Asian-Indians and associations with serum 25(OH)D and parathyroid hormone.

There is limited information on population-specific norms of trabecular-bone-score (TBS) and its associated factors. Here, we provide norms of TBS in Asian-Indians and its relationship with serum 25-hydroxyvitamin D [25(OH)D] and intact-parathyroid hormone (iPTH). TBS, bone-mineral-density (BMD), and vertebral-fractures (VFs) were assessed using dual-energy X-ray absorptiometry in 923 healthy Asian-Indians (aged 20-60 years). Serum 25(OH)D, iPTH, T4/TSH,, glycosylated-haemoglobin (HbA1c) were measured and associations with TBS assessed using multivariable linear regression. Subjects with BMD Z-score ≤ -2.0 or ≥2.0 at any sites, VFs, TSH > 10.0 or <0.05 µIU/ml, blood-glucose >11.1 mmol/L or HbA1c > 8.0% were excluded for generating Asian-Indian norms. TBS norms were generated in 744 healthy Asian-Indians (M:F,389:385). The cut-offs generated for 'normal', 'partially-degraded', and 'degraded' TBS were >1.305, 1.204-1.305 and <1.204, respectively. Mean TBS was lower in females than males (p < .001). There was 75% congruency in TBS categories between Asian-Indian and existing norms. Specificity (97.8 vs. 77.9%, p < .001) and diagnostic-accuracy (97.8% vs. 78.4%, p < .001) of TBS to detect osteoporosis were higher with Asian-Indian norms. The sensitivity of 'partially-degraded' TBS to diagnose osteopenia was also higher with Asian-Indian norms. In multivariable regression, gender, body-mass-index (BMI), BMD-L1-L4, serum PTH, daily dietary-calorie intake and calcium intake were associated with TBS. Though 25(OH)D inversely correlated with PTH, 25(OH)D was not associated with TBS. This study provides norms for TBS in Asian-Indians with gender-specific differences. Increasing age and higher BMI were associated with lower TBS. Associations of TBS with circulating PTH and/or 25(OH)D need confirmation in further studies.

Associations of childhood physical activity and screen time with cardiometabolic health in preteens who were born to mothers with previous macrosomic delivery: Findings from the ROLO longitudinal birth cohort study.

Macrosomia (birthweight ≥4 kg) may alter the associations of physical activity (PA) and screen time (ST) throughout childhood with later cardiometabolic risk. To investigate associations of PA and ST over a 4-6-year follow-up period with cardiometabolic outcomes in preteens (9-11-year-olds) who were born to mothers with previous macrosomic delivery. This is an analysis of 402 preteens from the ROLO study, who were born to mothers that previously delivered an infant with macrosomia. Parental-reported measures of PA and ST were obtained in early childhood at 5-years of age. Preteen self-reported PA, parental-reported ST, anthropometry, dual-energy x-ray absorptiometry, blood pressure, heart rate, cardiorespiratory endurance, and blood biomarkers were obtained at 9-11-years. Crude and adjusted linear regression models explored associations and the interaction of birthweight was investigated in all models. Early childhood PA and ST at the 5-year follow-up were not related to preteen cardiometabolic outcomes. In adjusted models, higher preteen PA was associated with lower sum of skinfolds (B = -3.00, 95% CI -5.98, -0.02, p = 0.048) and higher cardiorespiratory endurance (B = 0.50, 95% CI 0.20, 0.80, p = 0.001) at the same time point. No strong evidence for modification by birthweight was found. Higher preteen PA may have potential benefits for cardiometabolic health, irrespective of birthweight.

The difference in bone mineral density between femur and tibia is related to tibia deformation in endstage knee osteoarthritis

BackgroundThis study investigated bone mineral density (BMD) around the knee joint to clarify the mechanism by which tibia deformation exceeds that of the femur in patients with end-stage knee osteoarthritis (KOA). MethodsWe retrospectively analyzed 193 patients who underwent total knee arthroplasty for end-stage KOA with varus alignment. Preoperative T-score of the femur neck and femur total using dual-energy X-ray absorptiometry (DXA) and hounsfield units (HU) of the distal femur and proximal tibia using computed tomography (CT) were measured to asess the BMD. HU was measured by dividing the femur and tibia into medial, lateral, and total parts, respectively. Patients with medial proximal tibial angle (MPTA) ≥ 85° were considered ‘group 1′, and MPTA < 85° were ‘group 2′. The HU between femur and tibia were compared in group 1. T-score, HU, and HU difference between group 1 and group 2 were compared. ResultsThe HU of the proximal tibia was lower than that of the distal femur (femur lateral > femur medial > tibia medial > tibia lateral). T-score (femur neck, femur total) and HU (femur lateral, femur total, tibia lateral) were lower in group 2 than in group 1. There was no difference in femur-tibia HU difference between groups. ConclusionThe medial tibia collapse more than the medial femur in varus endstage KOA was associated with the lower BMD of the proximal tibia than that of the distal femur, and the MPTA collapse was affected by the absolute value of BMD rather than by the femur-tibia BMD difference.

Metabolic and hepatic phenotypes in sarcopenic obesity and impact of bariatric surgery

Background & AimsSarcopenic obesity (SO) is associated with cardiometabolic disorders and steatotic liver disease and carries major health risks. We assessed the hepatic and metabolic clinical phenotype associated with SO in patients with obesity undergoing bariatric surgery (BS). We also evaluated whether weight-loss and metabolic improvement post-surgery differ between patients with and without SO. Methods972 consecutive patients from a single-center BS cohort who underwent whole-body dual-energy X-ray absorptiometry (DXA) and peri-operative liver biopsy were included. SO was diagnosed using the AIM-SO score, an AI-assisted unbiased clustering algorithm based on body composition. One-year post-surgery, 862 patients were reassessed for AIM-SO score changes. ResultsPre-operatively, 207 (21.3%) patients were diagnosed with SO. These patients had significantly higher prevalence of type-2 diabetes (T2D), arterial hypertension and obstructive sleep apnea (OSA) compared to patients without SO (all p≤0.003). Patients with SO had more severe liver damage: higher grades of moderate/advanced steatosis (64.2% vs. 47.3%), steatohepatitis (44.4% vs. 32.3%) and advanced fibrosis (12.1% vs. 6.0%) (all p≤0.01). One-year post-BS, 58.5% of patients had remission of SO. Patients with persistent SO exhibited less weight-loss than those with SO remission (–23.8 kg vs. –29.1 kg, p<0.001) and had lower rates of remission for T2D (41.9% vs. 69.8%), arterial hypertension (20.8% vs. 45.3%), and metabolic syndrome (47.6% vs. 75.0%) (all p≤0.009). ConclusionThe DXA-based AIM-SO score identifies patients with SO who are at greater risk of hepatic and cardiometabolic comorbidities, and predicts less favorable weight-loss and metabolic improvements post-BS.

Tenofovir Disoproxil Fumarate/Emtricitabine Prophylaxis Has No Effect on Bone Mineral Density and Bone Mineral Content in African Breastfeeding Women Receiving Pre-Exposure Prophylaxis for HIV.

Tenofovir disoproxil fumarate (TDF) when used as preexposure prophylaxis (PrEP) in pregnancy is considered safe overall however there is insufficient evidence of its effect on maternal bone. We compared bone mineral density (BMD) and content (BMC) at the lumbar spine (LS) and hip of African breastfeeding women exposed and not exposed to TDF-containing PrEP in a randomized control trial (RCT). This is a secondary data analysis of an RCT where pregnant women were randomized to initiating PrEP in pregnancy or delayed initiation of PrEP until breastfeeding cessation. BMD and BMC at the LS and hip were measured using dual-energy x-ray absorptiometry (DXA) at 6, 26, 50, and 74 weeks postpartum. In an exploratory analysis, BMD at the hip and LS were evaluated against varying Tenofovir (TFV) levels during pregnancy. Of 300 women in the RCT who had a DXA at 6 weeks postpartum, 102 (66%) women in the Immediate PrEP arm and 105 (72%) in the Delayed PrEP arm had a 74-week DXA scan. Adjusting for breastfeeding duration and body mass index (BMI), there were no significant differences in BMD or BMC at the hip and LS between treatment arms. There was no consistent dose-effect of TFV-DP detected during pregnancy on BMD at the hip (p=0.231) or the LS (p=0.277). After adjusting for breastfeeding and BMI, TDF when given as oral preexposure prophylaxis during pregnancy had no deleterious effect on BMD and BMC at the hip and LS of African breastfeeding women.

Research on DXA bone density measurements and trabecular bone scores in Chinese men and women with obesity before and after bariatric surgery.

Dual energy X-ray absorptiometry (DXA) was used to analyze body composition, bone mineral density (BMD) parameters and the trabecular bone score (TBS) in patients with obesity before, 3 months after and 1 year after bariatric surgery as a method to evaluate the changes in BMD and skeletal microarchitecture (MA) in patients with obesity after bariatric surgery and to provide a basis for further accurate assessment of the bone health status of this population and subsequent treatment. This study was a retrospective analysis of 41 patients that underwent DXA imaging before, 3 months after and maximum 1 year after bariatric surgery. The follow-up rate in both periods was 100%. First, the changes in BMD and TBS before and after surgery were compared between patients grouped by sex and obesity degree. Secondly, the correlations between the TBS or BMD and body composition 1 year after surgery were analyzed. The BMD and TBS were within the normal range after bariatric surgery. Changes in the BMD and TBS were related to time, the degree of obesity and sex. Changes in the TBS were closely related to changes in the BMD, and the trends in the changes in the BMD were basically the same among the different groups of individuals with obesity of different sexes. A negative correlation was observed between the TBS and fat percentage (total body, leg, trunk, android area), as well as the lumbar spine Z-score in patients 1 year after bariatric surgery (p < 0.05). Bariatric surgery in patients with obesity has no obvious adverse effects on BMD or TBS. DXA can be used to better evaluate the changes in BMD and MA in patients with obesity after bariatric surgery, providing a basis for the clinical evaluation of post-bariatric surgery efficacy in these individuals and subsequent accurate assessment of the bone health status and treatment of this population.

Sarcopenic obesity in survivors of childhood acute lymphoblastic leukemia: prevalence, risk factors, and implications for cancer survivors.

Sarcopenic obesity, characterized by increased adiposity with low skeletal muscle mass, contributes to frailty and the development of chronic disease. Data on sarcopenic obesity in survivors of childhood acute lymphoblastic leukemia (cALL) is limited. A cross-sectional study on 65 cALL survivors (7-18years, > 2years from treatment completion) was conducted on cALL survivors with the primary outcome to determine the prevalence of sarcopenic obesity. Sarcopenic obesity was defined as patients with a positive Fat Mass Index (FMI) z-score with a negative Skeletal Muscle Index (SMI) z-score, measured using a Dual-Energy Xray Absorptiometry (DXA) scan. In addition, we assessed the factors associated with sarcopenic obesity by multivariable regression analysis. The mean (± SD) age was 12.9 (± 3.2) years, the median (Interquartile Range) time since diagnosis was 6.5 (5.9;8) years, and 66% received cranial radiotherapy. Central obesity, insulin resistance, and metabolic syndrome were seen in 21.5%, 23.1%, and 21% respectively. DXA-derived body composition variables revealed higher fat percentage despite normal body mass index (BMI) and lower muscle mass compared to the general population. Sarcopenic obesity was seen in 21 (34%) of survivors. On multivariable regression analysis, age at diagnosis (OR: 0.95 (95% CI: 0.92-0.98), p = 0.02), central obesity (OR: 18.99 (95% 2.32-155.5), p = 0.006) and insulin resistance (OR: 10.2 (95% CI: 1.75-59.09), p = 0.01) were associated with sarcopenic obesity. Sarcopenic obesity, an early clinical indicator for metabolic disease despite normal BMI, was significantly worse in children diagnosed with ALL at a younger age and was associated with central obesity and insulin resistance, which may contribute to adverse outcomes later in life.

Vertebral Bone Quality Score as a Predictor of Subsequent Fractures After Cement Augmentation for Osteoporotic Vertebral Compression Fracture.

Dual-energy X-ray absorptiometry (DXA) T-scores have been shown to predict fragility fractures in population-based studies. Recently, a novel MRI-based vertebral bone quality (VBQ) score has been proposed, showing better predictability for fragility fractures compared with DXA T-scores. The aim of this study was to explore the correlation between VBQ scores and DXA T-scores and to determine the impact of VBQ scores on the risk of subsequent fragility fractures after cement augmentation for osteoporotic vertebral compression fracture (OVCF). Between January and December 2018, 251 consecutive patients who received cement augmentation for OVCF were included in the study. VBQ scores were calculated using noncontrast T1-weighted MRI. Correlations between VBQ and T-scores were assessed. Patients were divided into 2 groups based on the presence or absence of subsequent fragility fractures after cement augmentation: (1) no Subsequent fracture group and (2) subsequent fracture group. Comparisons between the groups were conducted, and risk factors of subsequent fractures were evaluated using multivariable logistic regression analysis. Of the patients, 42 (16.7%) experienced subsequent fractures after cement augmentation. The VBQ score showed moderate correlations with the T-score of the hip (r = -0.523, P < .001) and the T-score of the lumbar spine (r = -0.383, P < .001). The subsequent fracture group had a significantly higher VBQ score (4.02 ± 0.56 vs 3.52 ± 0.62, P < .001) and a worse T-score of hip (-3.06 ± 1.28 vs -2.42 ± 0.98, P = .004). In the multivariable analysis, the VBQ score was the only independent predictor of subsequent fractures with 2.799 odds ratio (1.342 to 5.841, P = .006). In patients who received cement augmentation for OVCF, the VBQ score is significantly correlated with the DXA T-score and may be a more reliable predictor of subsequent fragility fractures.

Accuracy of Fat Mass and Muscle Mass Measured by Bioelectrical Impedance Analysis in Predicting Osteoporosis in Older Adults

Background: Osteoporosis is a prevalent bone disease characterized by reduced bone mineral density (BMD) and increased fracture risk. This study aimed to evaluate the accuracy of fat mass (FM) and muscle mass measured by bioelectrical impedance analysis (BIA) in predicting osteoporosis in older adults. Methods: A cross-sectional study was conducted on 109 outpatients aged 60 years and older. FM parameters (total fat mass, visceral fat level, and fat mass index [FMI]) and muscle mass parameters (total muscle mass, appendicular skeletal muscle mass [ASM], and appendicular skeletal muscle mass index [ASMI]) were measured using BIA. Osteoporosis was diagnosed based on BMD measurements using dual-energy X-ray absorptiometry (DXA). Receiver operating characteristic (ROC) curves were used to determine cut-off points and assess the accuracy of BIA parameters in predicting osteoporosis. Results: The prevalence of osteoporosis was 52.3% (n=57). The optimal cut-off points for predicting osteoporosis were: total fat mass &gt;36.25%, visceral fat level &gt;12.05, FMI &gt;7.82 kg/m2, total muscle mass &lt;37.82 kg, ASM &lt;16.795 kg, and ASMI &lt;6.895 kg/m2. Among the FM parameters, visceral fat level had the highest accuracy (AUC = 60.9%, sensitivity = 64.9%, specificity = 78.8%) while FMI had the lowest (AUC = 53.5%, sensitivity = 56.1%, specificity = 57.7%). For muscle mass parameters, ASM showed the highest accuracy (AUC = 74.0%, sensitivity = 70.2%, specificity = 76.9%). Conclusion: BIA-derived FM and muscle mass parameters, particularly visceral fat level and ASM can be used to predict osteoporosis in older adults with good accuracy. This non-invasive and accessible method may be useful as a screening tool for osteoporosis, especially in settings where DXA is unavailable.

Body Composition and Incident High-Intensity Back Pain and/or High Disability: A 10-Year Prospective Population-Based Male Cohort.

Back pain poses a significant global burden, within which individuals with more severe symptoms consume higher healthcare expenses than those with lesser back pain. Whether measures of body composition predict high-intensity back pain and/or high-disability in population-based cohorts is unknown. This study aimed to examine the association between body composition at baseline and their change in the prior 5 years (between 2001-2005 and 2006-2010) and incident high-intensity back pain and/or high-disability in long-term follow-up, 10 years later (2016-2021) in a population-based cohort of men. This study examined men with no or low-intensity back pain and disability (Graded Chronic Pain Scale) at back pain study baseline (2006-2010) within the Geelong Osteoporosis Study. Those developing high-intensity pain and/or high disability at follow-up (2016-2021) were identified. Weight, body mass index (BMI), abdominal circumferences, fat mass and lean mass (dual energy X-ray absorptiometry) were assessed prebaseline (2001-2005) and at baseline. The association of body composition at baseline and change in body composition from prebaseline to baseline with incident high-intensity pain and/or high disability at follow-up were examined using multivariable logistic regression. Of 695 participants with no or low-intensity pain and disability at baseline, 441 (62.3%) completed follow-up with a mean age of 54.3 ± 14.1 years: 37 (8.3%) developed high-intensity pain and/or high-disability, 33 (7.5%) developed high-intensity pain and 14 (3.2%) high disability. No measures of body composition at baseline were associated with incident high-intensity pain and/or high disability at follow-up in the whole population. In subgroup analysis, among men aged over 60 years, but not younger, higher lean mass was associated with decreased likelihood of high-intensity pain and/or high-disability (odds ratio [OR] 0.86, 95% confidence interval [CI] 0.76, 0.97, interaction p < 0.001). In the whole population, examination of the relationship between change in measures of body composition between prebaseline and baseline, only a one unit increase in BMI, equivalent to 3.1-kg weight gain, was associated with increased incident high disability (OR 1.63, 95% CI 1.06, 2.51). In a population-based sample, without severe back pain and disability, in older men aged ≥60 years, higher lean mass was protective of incident high-intensity pain and/or high disability. An increase in BMI, over 5 years, equivalent to 3.1-kg weight gain, was associated with incident back pain related high disability 10 years later. These results demonstrate another detrimental consequence of weight gain and highlight the importance of maintaining muscle mass in older men.

Assessing bone quality in hounsfield units using computed tomography: what value should be used to classify bone as normal or osteoporotic?

The purpose of this study was to investigate threshold values for classifying bone as normal or osteoporotic based on Computed Tomography (CT) Hounsfield Units (HU) and to determine if clinically applicable values could be derived to aid spine surgeons evaluating bone quality using CT. This literature review was completed using PubMed and Ovid (MedLine), using syntax specific to bone quality and CT. The included articles were original clinical studies assessing bone quality and utilized composite L1-L4 HU values compared against dual-energy X-ray absorptiometry (DEXA) values. Extracted data study descriptors, CT measurement technique, and CT threshold values. CTs were measured from L1-L4 using either axial or sagittal images, and must classify their bone quality findings for any of the following 3 categories: normal, osteopenia, or osteoporosis. This review located 34 studies measuring bone density using CT with threshold values, of which, 10 were included in the final review. Number of patients ranged from 74 to 283 and cohort ages from 20s to 70.6 years. CT threshold values for assessing normal and osteoporotic bone quality ranged from 150 to 179 and 87 to 155, respectively. From combining values across studies, a HU value of ≥ 170 HU was associated with normal bone and ≤ 115 HU with osteoporosis. There is variation in HU values used to differentiate normal from compromised bone quality, even after limiting studies. For patients with HU values between or near 170 or 115 HU, a DEXA scan may be warranted for further evaluation. With ongoing investigation in this area, threshold values for classifying bone quality using CT will be continually refined.

Associations of linear growth and weight gain in the first 2 years with bone mass at 4 years of age in children in Dhaka, Bangladesh.

Growth faltering is widespread in many low- and middle-income countries, but its effects on childhood bone mass accrual are unknown. The objective of this study was to estimate associations between length (conditional length-for-age z-scores, cLAZ) and weight (conditional weight-for-age z-scores, cWAZ) gain in 3 age intervals (ages 0-6, 6-12, 12-24 months) with dual-energy x-ray absorptiometry (DEXA)-derived measures of bone mass (total-body-less-head (TBLH) bone mineral content (BMC), areal bone mineral density (aBMD), and bone area) at 4 years of age. Associations between interval-specific growth parameters (cLAZ and cWAZ) and bone outcomes were estimated using linear regression models, adjusted for maternal, child, and household characteristics. Data collection occurred in Dhaka, Bangladesh. 599 healthy children enrolled in the BONe and mUScle Health in Kids Study. cLAZ in each age interval was positively associated with TBLH BMC, aBMD, and bone area at 4 years; however, associations attenuated towards null upon adjustment for concurrent height-for-age z-scores (HAZ) at age 4 years and confounders. cWAZ from 0-6 and 6-12 months was not associated with bone mass, but every SD increase in cWAZ between 12-24 months was associated with greater BMC (7.6g; 95%CI:3.2, 12.0) and aBMD (0.008g/cm2; 95%CI:0.003, 0.014) after adjusting for concurrent WAZ, HAZ, and confounders. Associations of linear growth (birth to 2 years) with bone mass at age 4 years were explained by concurrent HAZ. Weight gain in the second year of life may increase bone mass independently of linear growth in settings where growth faltering is common.

Gut microbiota and short-chain fatty acids signatures in postmenopausal osteoporosis patients: A retrospective study

Studies have shown that gut microbiota (GM) and its metabolites, short-chain fatty acids (SCFAs), are associated with the development of postmenopausal osteoporosis (PMO). This study explored the clinical and laboratory evidence of the relationship of GM and SCFAs to PMO and attempted to determine the potential mechanism of action. 18 patients (Collected from the First Affiliated Hospital of Guangdong Pharmaceutical University between January 2021 and August 2021) were included in this retrospective study, including 10 PMO women and 8 healthy young women as the healthy control (HC) group from Guangzhou, China. Bone mineral density (BMD) was determined by dual-energy X-ray absorptiometry. The composition of GM and its metabolites, SCFAs, in the fecal samples were measured by 16S rRNA gene sequencing and gas chromatography/mass spectrometry analysis, respectively. Compared with healthy control, PMO group had significantly decreased BMD in lumbar spines 1-4 (BMD_L) and femoral neck (BMD_F). 16S rRNA gene sequencing revealed that, compared with healthy control, PMO group had a markedly decreased abundance in Subdoligranulum, Norank_f_Muribaculaceae, and Alistipes at the genus level. Gas chromatography/mass spectrometry analysis indicated that the concentration of propanoic acid significantly dropped in PMO group. Additionally, we found that Subdoligranulum, Norank_f_Muribaculaceae, and Alistipes were positively correlated with BMD_L. Subdoligranulum and Norank_f_Muribaculaceae were also positively correlated BMD_F and propanoic acid, while Subdoligranulum is the only species that presented a strong correlation with the levels of acetic acid and butyric acid. Our findings indicated that, in postmenopausal women, there were evident changes in GM and SCFAs, and these changes were found correlated with patients’ BMD. These correlations provide novel insights into the underlying mechanism of PMO development, representative of early diagnostic markers and therapeutic targets that may improve the bone health in postmenopausal women.

High prevalence of osteoporosis among virally suppressed older people (≥60 years) living with HIV.

Our objective was to evaluate bone mineral density (BMD) among older people living with HIV at the time of enrolment into a clinical trial in Kenya. The bictegravir/emtricitabine/tenofovir alafenamide (BFTAF) Elderly Study is a clinical trial among virally suppressed people living with HIV aged ≥60 years randomized to switch to BFTAF or continue their pre-enrolment regimen. At enrolment, dual-energy x-ray absorptiometry (DXA) of the lumbar spine, total hip, and femoral neck was performed and T-scores calculated for BMD. Osteoporosis was defined as T-score -2.5 or lower and osteopenia as T-score between -1 and -2.5. Fracture risk was calculated based on clinical risk factors (not including BMD), considering HIV as a secondary cause of osteoporosis, and the correlation between FRAX®-HIV and BMD assessed. Between February and May 2022, a total of 296 participants were enrolled. All were Black African, 147 (49.7%) were female, the median age was 64 years (range 60-77), and 280 (94.6%) were on tenofovir disoproxil fumarate. The median BMD of lumbar spine, total hip, and femoral neck was 0.87 g/cm2 (interquartile range [IQR] 0.78-0.99), 0.89 g/cm2 (IQR 0.79-1.01), and 0.75 g/cm2 (IQR 0.67-0.84), respectively, with median T-scores of -1.9 (IQR -2.8 to -0.7), -1.0 (IQR -1.9 to -0.3), and -1.5 (IQR -2.2 to -0.9), respectively. Osteoporosis and osteopenia were found in 37.5% and 47.3% of participants, respectively. Major osteoporotic fracture and hip fracture 10-year median probabilities using FRAX®-HIV were 3.4% (IQR 2.8-4.6) and 1.0% (IQR 0.7-1.3). Correlation coefficients between these FRAX®-HIV probabilities and femoral neck BMD were -0.204 for major osteoporotic fracture and -0.338 for hip fracture. The prevalence of osteoporosis is high among older people living with HIV in Kenya, where DXA is not readily available and risk calculation without BMD had low correlation with measured BMD values. Additional data are required on the impact of investment in fracture risk assessment and treatment, including population-specific risk calculators.

Serum IL-6 and TGF-β1 concentrations as diagnostic biomarkers in elderly male patients with osteoporosis.

This research is intended to evaluate the correlations of serum IL-6 and TGF-β1 concentrations with bone density and turnover markers as well as their diagnostic value in elderly male patients with osteoporosis (OP). A retrospective analysis was conducted on 335 elderly men (≥ 60years; 90 with normal bone mass, 120 osteopenia cases, and 125 OP cases). Lumbar spine/femoral neck BMD values were measured using dual-energy X-ray absorptiometry. Correlations of serum IL-6 and TGF-β1 concentrations with bone density and bone turnover markers in OP patients were analyzed utilizing Pearson or Spearman correlation coefficients. Independent influencing factors for OP were identified by logistic multivariate regression analysis. The diagnostic value of serum IL-6 and TGF-β1 was assessed with ROC curves and MedCalc software. Smoking history, drinking history, lumbar spine BMD, femoral neck BMD, PINP, and β-CTX markedly differed among the normal bone mass, osteopenia, and OP groups. Elevated IL-6 and reduced TGF-β1 concentrations were observed in serum samples of OP. Serum IL-6 concentrations was inversely associated with bone density markers but positively lined to bone turnover markers. Conversely, serum TGF-β1 was positively related to bone density markers but negatively associated with bone turnover markers. Smoking history, PINP, and IL-6, were identified as independent risk factors while lumbar spine BMD, femoral neck BMD, and TGF-β1 were independent protective markers for OP. The combined assessment of serum IL-6 and TGF-β1 showed superior diagnostic performance for OP. Serum IL-6 in combination with TGF-β1 exhibits good diagnostic performance for OP. Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

Upper limb muscle strength and wheelchair-related abilities following an exoskeleton-assisted walking programme in individuals with chronic spinal cord injury: An exploratory study.

To measure the potential effects of an overground exoskeleton-assisted walking programme on upper limb strength and mass, as well as on wheelchair propulsion performances and abilities in individuals with chronic spinal cord injury. Prospective, single-group, pre-post intervention study. Ten individuals with chronic (≥ 18 months) spinal cord injury who use a wheelchair as their primary mode of locomotion and who had little-to-no motor function in the lower limbs. Individuals completed a progressive 16-week exoskeleton-assisted walking programme (34 × 1-h sessions, 1-3 sessions/week). Upper limb muscle strength was measured with dynamometers (isokinetic, Jamar). Upper limb lean mass (dual-energy X-ray absorptiometry) was used to calculate relative strength. Field tests (20-m wheelchair propulsion, and slalom test) and the Wheelchair Skills Test Questionnaire determined performances and abilities. Wilcoxon signed-rank tests were used with the following criteria: p < 0.1, effect size ≥ 0.5, and relative variation > 5%. Only natural velocity during the 20-m wheelchair propulsion test (i.e., fundamental wheelchair ability) changed following the intervention (p = 0.01, effect size = 0.82, relative variation = +14.5%). Overall, upper limb muscle function did not significantly and meaningfully change following the exoskeleton-assisted walking programme in this population. Additional research is needed to verify how changes in training volume would affect strength and advanced wheelchair-related abilities and performance, as well as the response in individuals who are deconditioned or novices to wheelchair use (e.g., subacute spinal cord injury).

Association of obstructive sleep apnea with bone metabolism in older adults: a hospital-based study

PurposeObstructive sleep apnea (OSA) significantly affects patients’ quality of life; however, the mechanisms, such as its effects on bone mineral density (BMD) and bone turnover marker (BTM) expression, remain unclear. In this study, we investigated the relationships among OSA, BMD, and (BTMs) in older adults.MethodsThis retrospective study enrolled 260 participants (114 women; 44.5%). Data of an established system (Alice NightOne) were used to diagnose OSA and analyze nocturnal hypoxia. Participants were divided into four groups according to respiratory event index (REI) (control, < 5 times/hour; mild OSA, 5–15 times/hour; moderate OSA 15–30 times/hour; severe OSA ≥ 30 times/hour). BMD were mesured by dual-energy x-ray absorptiometry. BTMs including bone specific alkaline phosphatase (BALP), tartrate-resistant acid phosphatase 5b (TRAP-5b) were collected.ResultsPatients with OSA had higher BMD at first lumbar vertebra, left and right femur than those without (all p < 0.05). REI was positively correlated with BMD at the first lumbar vertebra (r = 0.181, p = 0.006), left femur (r = 0.160, p = 0.014), and right femur (r = 0.243, p < 0.001). In participants with body mass index (BMI) of 18–24 kg/m2 (N = 96), the correlation between REI and BMD at the left femur(r = 0.251, p = 0.019) and right femur (r = 0.258, p = 0.018) remained. Multiple regression analysis showed that OSA was significantly associated with osteoporosis (p = 0.034, 95% confidence interval, 0.092–0.100, odds ratio, 0.092). MSaO2 was positively correlated with TRAP5b (r = 0.560, p = 0.007). In participants with a BMI of ≥ 24 kg/m2(N = 164), MSaO2 was negatively correlated with BALP (r = −0.331, p = 0.034). No significant association between REI and BMD was observed.ConclusionsOSA and hypoxia were associated with higher BMD in older adults in BMI of 18–24 kg/m2 but not in participants with a BMI of ≥ 24 kg/m2. This study suggests a negative association between OSA and osteoporosis in non-overweight and obese population. BMI played an important role. The study’s findings could help exploration mechanisms of osteoporosis and promoting its treatment.

Effect of vitamin D, omega-3 supplementation, or a home exercise program on muscle mass and sarcopenia: DO-HEALTH trial.

We aimed to investigate the effect of daily supplemental vitamin D, omega-3s, and a thrice-weekly home exercise program, alone or in combination, on change of appendicular lean muscle mass index (ALMI) and incident sarcopenia in older adults. This is a secondary endpoint analysis of a 3-year randomized, double-blind, placebo-controlled trial with a 2 × 2 × 2 factorial design among 2157 community-dwelling, healthy adults aged 70 + years, from 2012 to 2018 (DO-HEALTH). Participants were randomized to 2000 IU/d vitamin D and/or 1 g/d marine omega-3s and/or exercise. Change in ALMI over 3 years was calculated in all participants who underwent dual energy X-ray absorptiometry (DXA) (n = 1495) using mixed effect models. Incident sarcopenia was analyzed based on the Sarcopenia Definitions and Outcomes Consortium in all non-sarcopenic participants (n = 1940). Among 1495 participants (mean age 74.9 (sd 4.4); 63.3% were women; 80.5% were at least moderately physically active at baseline) mean gait speed at baseline was 1.2 m/s (sd 0.3), mean ALMI at baseline was 6.65 (SD 0.95) in women, and 8.01 (SD 0.88) kg/m2 in men. At year 3, average change of ALMI was -0.09 (sd 0.34) kg/m2 (-1.35%) in women and - 0.17 (sd 0.33) kg/m2 (-2.0%) in men. None of the treatments individually or in combination had a benefit on ALMI change compared to control over 3 years, with omega-3s showing a small protective effect on ALMI at year 1 only (-0.021 vs. no-omega-3s -0.066 kg/m2, p = 0.001). Of 1940 non-sarcopenic participants at baseline, 88 (4.5%) developed incident sarcopenia over 3 years. None of the treatments individually or in combination reduced the odds of incident sarcopenia compared with placebo. Among healthy, physically active older adults, ALMI and incidence of sarcopenia were not improved by treatment of daily 2000 IU vitamin D, daily 1 g omega-3s, or a simple home exercise program compared with control over 3 years.

Validation of Ultrasound Measurement of Vastus Lateralis for Appendicular Skeletal Muscle Mass in Chronic Kidney Disease Patients with Hemodialysis.

Chronic kidney disease patients undergoing hemodialysis (HD) are at a high risk of developing sarcopenia. This study aimed to validate the performance of ultrasound (US) measurements of the vastus lateralis (VL) for estimating muscle mass and diagnosing sarcopenia in CKD patients with HD. Forty-six patients were enrolled in this study. Muscle thickness (MT) and echo intensity (EI) of VL, physical performance, and biochemical markers were collected to establish a linear regression model for predicting appendicular skeletal muscle mass (ASM), using dual-energy X-ray absorptiometry (DXA) as the reference standard. The model's performance was validated, and its diagnostic accuracy for sarcopenia was also evaluated. An ASM prediction model was derived: -20.17 + 1.90 × MT_VL (cm) + 1.58 × male + 0.16 × Height (cm) + 0.09 × Weight (kg) + 0.05 × Age (year), with a standard estimated error of 1.44 kg and adjusted R-squared of 0.84. The model exhibited high correlation and an acceptable limit of agreement, compared to DXA measurement. EI displayed a negative correlation with ASM and MT. The ASM adjusted with BMI demonstrated superior performance in diagnosing sarcopenia compared to the ASM adjusted with height. Ultrasound provides a cost-effective bedside tool for evaluating muscle conditions in HD patients.