Postmenopausal women with higher TSH values within the normal range present improved handgrip strength: a pilot study.

OBJECTIVE: To evaluate the possible association between thyroid function within the euthyroid range and musculoskeletal parameters as well as body composition in a sample of postmenopausal women. METHODS: This cross-sectional study included 96 postmenopausal women with serum thyroid-stimulating hormone (TSH) within the normal laboratory reference range. Fasting venous blood samples were obtained for biochemical/hormonal assessment. Bone status and body composition were measured using Dual Energy X-ray absorptiometry (DXA). Physical activity was quantified using the International Physical Activity Questionnaire (IPAQ) index. RESULTS: Serum TSH correlated with handgrip strength (HGS, r-coefficient = 0.233, p = .025), and total body bone mineral density (BMD) T-score values (r-coefficient = 0.321, p = .003). HGS measures were associated with BMD (r-coefficient = 0.415, p < .001), with bone mineral content (BMC, r-coefficient = 0.427, p < .001), and lean mass (r-coefficient = 0.326, p = .003). Women with low muscle strength, defined as HGS < 16 kg, had lower TSH levels than women with normal muscle strength (low vs. normal muscle strength, ANCOVA 1.13 ± 0.49 mU/L vs. 1.60 ± 0.83 mU/L, p = 0.024) independently of age, BMD, percentage of body fat or absolute lean mass. Multivariable linear regression analysis showed that HGS values were associated with TSH measurements (ß-coefficient = 0.246, p = .014) and BMD T-score values (ß-coefficient = 0.306, p = .002). All models were adjusted for age, body mass index (BMI), vitamin D, low-density lipoprotein cholesterol, current smoking, physical activity, and homeostasis model assessment of insulin resistance. CONCLUSIONS: In this sample of postmenopausal women, lower serum TSH values, within normal range, were associated with lower muscle strength compared to higher normal TSH values. Further research is needed to elucidate the significance of our preliminary findings.

Resistance training presents beneficial effects on bone development of adolescents engaged in swimming but not in impact sports: ABCD Growth Study.

BACKGROUND: Sports practice during adolescence is important to enhance bone development, although it may provide different effects depending on the mechanical impact present in the sport. Besides, resistance training (RT) may also induce bone changes directly (via muscle contractions) and indirectly (via myokines). However, there have been no studies analyzing the longitudinal influence of engaging in sport with and without added mechanical load. Thus, this study aims to analyze the combined effects of sports participation and resistance training on areal bone mineral density (aBMD) accrual in adolescent athletes participating in swimming and impact sports for 12-months. METHODS: This was a 12-month longitudinal study. The sample comprised 91 adolescents (21 females) aged 10 to 18 years, engaged in impact sports (basketball, tennis, track & field, baseball and gymnastics, n = 66) and non-impact sport (swimming, n = 25). The sample was divided according to resistance training participation: impact sports only (n = 45), impact sports + resistance training (n = 21), swimming-only (n = 17) and swimming + resistance training (n = 8). aBMD and soft tissues were measured using dual-energy X-ray absorptiometry. Generalized linear models analysis was used for the resistance training (RT) x type of sport interaction in predicting aBMD changes overtime, adjusting for maturation, sex and baseline aBMD. RESULTS: After 12-months, all groups showed a significant increase in aBMD, except for the swimming groups (regardless of resistant training), which showed a significant loss in spine aBMD (-0.045 [-0.085 to -0.004] g/cm2 in swimming-only and - 0.047 [-0.073 to -0.021] g/cm2 in swimming + RT). In comparisons between groups, only swimming + RT group, compared with swimming-only group presented higher upper limbs aBMD (0.096 g/cm2 [0.074 to 0.118] in swimming + RT vs. 0.046 [0.032 to 0.060] g/cm2 in swimming only; p < 0.05) and whole body less head (WBLH) aBMD (0.039 [0.024 to 0.054] g/cm2 in swimming + RT vs. 0.017 [0.007 to 0.027] g/cm2 swimming-only; p < 0.05). CONCLUSION: Despite the significant gain in aBMD in all groups and body sites after 12-months, except for the spine site of swimmers, the results indicate that participation in RT seems to improve aBMD accrual in swimmers at the upper limbs and WBLH.

Assessment of Biochemical Bone Turnover Markers in Polish Healthy Children and Adolescents.

BACKGROUND: Assessing bone turnover in paediatric populations is crucial for understanding the physiological changes occurring during skeletal development and identifying potential abnormalities. The objective of this study was to assess osteocalcin (OC), bone alkaline phosphatase (BALP), and C-terminal telopeptide of type I collagen (CTX-I) levels reflecting bone formation and resorption for age and sex in Polish healthy children and adolescents. MATERIALS AND METHODS: A total of 355 healthy normal-weight children and adolescents (46.5% girls) aged 1-18 years old were recruited. Total body less head (TBLH) and spine L1-L4 were used in children to assess bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA). Bone marker concentrations were determined by immunoenzymatic methods. RESULTS: Bone marker levels in girls and boys started with higher values in the first year of life and subsequently decreased until reaching a nadir during the prepubertal period. The pubertal peak values of bone markers were reached at 11-13 years old in boys and at 9-11 years old in girls. After puberty, the adolescents showed a gradual decline in bone marker concentrations to the values observed in adults. We found positive correlations between OC level and TBLH-BMD (r = 0.329, p = 0.002), TBLH-BMD Z-score (r = 0.245, p = 0.023), and L1-L4 BMD (r = 0.280, p = 0.009) in the prepubertal group. CONCLUSIONS: We showed serum levels of bone turnover markers-BALP, OC, and CTX-I-in relation to age and sex in healthy Polish children and adolescents. The age intervals of these markers for girls and boys aged 1-18 years old may be clinically useful in the assessment of bone metabolism in individuals with skeletal disorders.

Backscatter measurement of cancellous bone using the ultrasound transit time spectroscopy.

Recently, ultrasound transit time spectroscopy (UTTS) was proposed as a promising method for bone quantitative ultrasound measurement. Studies have showed that UTTS could estimate the bone volume fraction and other trabecular bone structure in ultrasonic through-transmission measurements. The goal of this study was to explore the feasibility of UTTS to be adapted in ultrasonic backscatter measurement and further evaluate the performance of backscattered ultrasound transit time spectrum (BS-UTTS) in the measurement of cancellous bone density and structure. First, taking ultrasonic attenuation into account, the concept of BS-UTTS was verified on ultrasonic backscatter signals simulated from a set of scatterers with different positions and intensities. Then, in vitro backscatter measurements were performed on 26 bovine cancellous bone specimens. After a logarithmic compression of the BS-UTTS, a linear fitting of the log-compressed BS-UTTS versus ultrasonic propagated distance was performed and the slope and intercept of the fitted line for BS-UTTS were determined. The associations between BS-UTTS parameters and cancellous bone features were analyzed using simple linear regression. The results showed that the BS-UTTS could make an accurate deconvolution of the backscatter signal and predict the position and intensity of the simulated scatterers eliminating phase interference, even the simulated backscatter signal was with a relatively low signal-to-noise ratio. With varied positions and intensities of the scatterers, the slope of the fitted line for the log-compressed BS-UTTS versus ultrasonic propagated distance (i.e., slope of BS-UTTS for short) yield a high agreement (r2 = 99.84%-99.96%) with ultrasonic attenuation in simulated backscatter signal. Compared with the high-density cancellous bone, the low-density specimen showed more abundant backscatter impulse response in the BS-UTTS. The slope of BS-UTTS yield a significant correlation with bone mineral density (r = 0.87; p < 0.001), BV/TV (r = 0.87; p < 0.001), and cancellous bone microstructures (r up to 0.87; p < 0.05). The intercept of BS-UTTS was also significantly correlated with bone densities (r = -0.87; p < 0.001) and trabecular structures (|r|=0.43-0.80; p < 0.05). However, the slope of the BS-UTTS underestimated attenuation when measurements were performed experimentally. In addition, a significant non-linear relationship was observed between the measured attenuation and the attenuation estimated by the slope of the BS-UTTS. This study demonstrated that the UTTS method could be adapted to ultrasonic backscatter measurement of cancellous bone. The derived slope and intercept of BS-UTTS could be used in the measurement of bone density and microstructure. The backscattered ultrasound transit time spectroscopy might have potential in the diagnosis of osteoporosis in the clinic.

Bone quality assessment in patients with healing mandibular fracture sites: a computed tomography investigation.

The objective of this retrospective study was to assess the bone quality of healing mandibular fracture sites by measuring the Hounsfield units (HU) on computed tomographic (CT) images obtained presurgery and postsurgery in patients treated with rigid internal fixation (RIF). The HU values of healing fracture sites were compared to those of corresponding nonfractured (control) sites on the opposing side and cervical vertebrae sites in the same patients. In total, 31 patients with 45 mandibular fractures treated with RIF underwent presurgical and postsurgical CT examinations. The scans performed after surgery (1, 3, 6, 12, or 18 months) were taken only when there was a need for radiographic evaluation due to a complaint of discomfort from the patient or when the surgeon needed to verify the postsurgical outcome, and each patient underwent only a single postsurgical CT. At the presurgical CT examination, the HU values were lower in the fracture sites than in the control sites. At 3 months postsurgery, the HU values in the fracture sites had increased as the mandibular bone healed. At 6 months postsurgery, the HU values in the fracture sites were higher than those of the control sites. At 12 and 18 months postsurgery, the HU values of both sites were similar. The HU values of the cervical vertebrae remained constant with time. These results suggest that, in patients who have been treated with RIF for mandibular bone fracture, HU values measured by CT vary across time, expressing the physiologic bone healing process.

Association of sarcopenia with osteoporosis in Chinese patients with type 2 diabetes.

BACKGROUND: People with type 2 diabetes mellitus (T2DM) present a higher tendency to develop sarcopenia and osteoporosis compared with the normal population. Currently, osteoporosis screening has been frequently performed among T2DM patients, but sarcopenia screening is relatively less, and the association between the two diseases remains unclear. Herein, this study aims to determine the association between sarcopenia and osteoporosis in Chinese T2DM patients. METHODS: This was a retrospective study of 678 patients with T2DM in the First Affiliated Hospital of Wenzhou Medical University. The bone mineral density (BMD) and muscle mass were measured by using dual-energy X-ray absorptiometry scanning. The diagnostic criteria of sarcopenia referred to the consensus by the Asia Working Group for Sarcopenia (AWGS). RESULT: Among T2DM patients, the proportion of the sarcopenia population complicated with osteoporosis was higher than that of the non-sarcopenia (30.9% vs. 8.6% in men and 46.9% vs. 33.9% in women), but only significantly in men. The BMD of the hip and femoral neck was positively correlated with skeletal muscle mass index (SMI), grip strength, and gait speed (P < 0.01). After adjusting all covariates, the association between sarcopenia and BMD showed odds ratios of 0.43 (95% CI:0.28-0.66) for the femoral neck and 0.49 (95% CI:0.32-0.73) for the hip. CONCLUSIONS: The BMD of the hip and femoral neck in T2DM patients is related to sarcopenia-related indicators and represents an independent protective factor for sarcopenia. To reduce the risk of falls, fractures, and weakness, it is necessary to take sarcopenia assessment in people with T2DM and osteopenia/osteoporosis.

Novel Biomarkers of Bone Metabolism.

Bone represents a metabolically active tissue subject to continuous remodeling orchestrated by the dynamic interplay between osteoblasts and osteoclasts. These cellular processes are modulated by a complex interplay of biochemical and mechanical factors, which are instrumental in assessing bone remodeling. This comprehensive evaluation aids in detecting disorders arising from imbalances between bone formation and reabsorption. Osteoporosis, characterized by a reduction in bone mass and strength leading to heightened bone fragility and susceptibility to fractures, is one of the more prevalent chronic diseases. Some epidemiological studies, especially in patients with chronic kidney disease (CKD), have identified an association between osteoporosis and vascular calcification. Notably, low bone mineral density has been linked to an increased incidence of aortic calcification, with shared molecules, mechanisms, and pathways between the two processes. Certain molecules emerging from these shared pathways can serve as biomarkers for bone and mineral metabolism. Detecting and evaluating these alterations early is crucial, requiring the identification of biomarkers that are reliable for early intervention. While traditional biomarkers for bone remodeling and vascular calcification exist, they suffer from limitations such as low specificity, low sensitivity, and conflicting results across studies. In response, efforts are underway to explore new, more specific biomarkers that can detect alterations at earlier stages. The aim of this review is to comprehensively examine some of the emerging biomarkers in mineral metabolism and their correlation with bone mineral density, fracture risk, and vascular calcification as well as their potential use in clinical practice.

How to Suppress Mineral Loss and Stimulate Anabolism in Postmenopausal Bones with Appropriate Timing of Exercise and Nutrients.

Background. Bone Health and Osteoporosis Foundation (BHOF) reports that as of 2023, approximately 10 million of older Americans have osteoporosis and another 44 million have low bone density. Osteoporosis is a serious handicap for the elderly and, in particular, for estrogen-deficient postmenopausal women, as it increases the risk of debilitating bone weakness and fractures. The BHOF recommendations for prevention of osteopenia, osteoporosis and bone fractures are to perform weight-bearing and muscle-strengthening exercises and to take recommended amounts of daily calcium and vitamin D. Methods. The purpose of this review is to describe and discuss recent evidence-based research on how to effectively utilize timing of exercise and calorie intake for stimulation of postmenopausal bone anabolism, and to provide this new information in the form of specific and actionable recommendations. Results. The five evidence-based recommendations are as follows: 1. Select an appropriate circadian time of day for exercise; 2. Increase walking speed to raise the movement momentum; 3. Eat a weight-maintenance meal one or two hours before the exercise bout; 4. Sustain the duration of walking activity (impulse) for 40 to 45 min; and 5. Repeat effective exercise stimulus 7 to 8 h after the first one to double the anabolic effect. Osteogenesis can also be increased with subthreshold mechanical loading, where needed, under several special circumstances. Conclusions. This review should provide pragmatic actionable pointers on how to utilize the idiosyncratic bone responsiveness to timing of movement and meals to prevent osteoporosis and encourage research toward a better understanding of how bone detects adequacy of a mechanical stimulus and determines duration of necessary rest to recover its sensitivity to mechanical stimulation and nutrients.

Bone involvement in the early stages of Parkinson's disease: a case-control study.

OBJECTIVE: To evaluate the qualitative and quantitative alterations of bone tissue in patients with early-stage Parkinson's disease (PD) and to measure the associations between bone mineral density (BMD), trabecular bone score (TBS) and physical performance. METHODS: This case-control study enrolled patients with early-stage PD and age-matched controls. BMDs for the left femoral neck (L-FN) and lumbar spine (LS) were measured. Bone microarchitecture for the LS was determined using TBS. Muscle performance was assessed using the short physical performance battery (SPPB). Patients and controls were stratified in two groups based on the SPPB score: a poor performance group (SPPB score ≤8) and high performance group (SPPB > 8). RESULTS: This study included 26 patients: 13 in the PD group and 13 age-matched controls. The mean ± SD BMD results in the PD group were: L1-L4 BMD = 0.935 ± 0.183 g/cm2; L-FN BMD = 0.825 ± 0.037 g/cm2; with bone microarchitecture degraded in four patients and partially degraded in three patients. TBS was significantly different in the patients with PD stratified according to SPPB. Among the controls, there was a significant difference in body mass index between the two SPPB groups. CONCLUSION: TBS might identify bone involvement earlier than BMD in the initial stages of PD.

Precision Errors and Monitoring Time Interval in Pediatric Muscle Imaging and Neuromuscular Performance Assessment.

OBJECTIVES: To determine precision errors and monitoring time intervals in imaged muscle properties and neuromuscular performance, and to explore growth-related factors associated with precision errors in children. METHODS: We included 35 children (mean age 10.5yrs) in the precision study cohort and 40 children (10.7yrs) in the follow-up study cohort. We assessed forearm and lower leg muscle properties (area, density) with peripheral quantitative computed tomography. We measured neuromuscular performance via maximal pushup, grip force, countermovement and standing long jump force, power, and impulse along with long jump length. We calculated precision errors (root-mean-squared coefficient of variation) from the precision cohort and monitoring time intervals using annual changes from the follow-up cohort. We explored associations between precision errors (coefficient of variation) and maturity, time interval (between repeated measures), and anthropometric changes using Spearman's rank correlation (p<0.05). RESULTS: Muscle measures exhibited precision errors of 1.3-14%. Monitoring time intervals were 1-2.6yrs, except muscle density (>43yrs). We identified only one association between precision errors and maturity (maximal pushup force: rho=-0.349; p=0.046). CONCLUSIONS: Imaging muscle properties and neuromuscular performance measures had precision errors of 1-14% and appeared suitable for follow-up on ~2yr scales (except muscle density). Maximal pushup force appeared more repeatable in mature children.

The Association between Obesity and Reduced Weight-Adjusted Bone Mineral Content in Older Adults: A New Paradigm That Contrasts with the Obesity Paradox.

The relationship between body weight and bone mass in the elderly remains unclear, and whether obesity is a protective factor is still a matter of debate. For this reason, the aim of this study is to assess the association between body mass index (BMI) and bone mineral content adjusted by body weight, expressed as a percentage (w-BMC%), and to test the validity of the obesity paradox in this context. A cohort of 1404 older adults was categorized according to the World Health Organization's BMI cut-off points and completed a total and segmental body composition measurement by means of a dual X-ray absorptiometry scan. Individuals with obesity displayed a lower mean w-BMC% (3.06 ± 0.44%; 2.60 ± 0.37%) compared to those who were normal-weight (3.95 ± 0.54%; 3.38 ± 0.48%) and overweight (3.06 ± 0.44%; 3.04 ± 0.37%) in both genders. Linear regression analysis also showed a negative association between BMI and w-BMC% in males (ß = -0.09; p < 0.001) and females (ß = -0.06; p < 0.001). Finally, among individuals with obesity, and after adjusting for age, the linear regression models revealed a significant decrease of 0.75% and 0.28% in w-BMC% for every one-unit increase in the trunk fat/appendicular lean mass ratio in both males (ß = -0.749; p < 0.0001) and females (ß = -0.281; p < 0.001). In conclusion, we suggest a new paradigm regarding the impact of obesity on bone mass, in which the former does not appear to be a protective factor of the latter, especially in individuals with central obesity and low muscle mass.

Machine learning predicts the risk of osteoporosis in patients with breast cancer and healthy women.

OBJECTIVE: In this study, we investigated the effects of endocrine therapy and related drugs on the body composition and bone metabolism of patients with breast cancer. Additionally, using body composition-related indicators in machine learning algorithms, the risks of osteoporosis in patients with breast cancer and healthy women were predicted. METHODS: We enrolled postmenopausal patients with breast cancer who were hospitalized in a tertiary hospital and postmenopausal women undergoing health checkups in our hospital between 2019 and 2021. The basic information, body composition, bone density-related indicators, and bone metabolism-related indicators of all the study subjects were recorded. Machine learning models were constructed using cross-validation. RESULTS: Compared with a healthy population, the body composition of patients with breast cancer was low in bone mass, protein, body fat percentage, muscle, and basal metabolism, whereas total water, intracellular fluid, extracellular fluid, and waist-to-hip ratio were high. In patients with breast cancer, the bone mineral density (BMD), Z value, and T value were low and the proportion of bone loss and osteoporosis was high. BMD in patients with breast cancer was negatively correlated with age, endocrine therapy status, duration of medication, and duration of menopause, and it was positively correlated with body mass index (BMI) and basal metabolism. The parameters including body composition, age, hormone receptor status, and medication type were used for developing the machine learning model to predict osteoporosis risk in patients with breast cancer and healthy populations. The model showed a high accuracy in predicting osteoporosis, reflecting the predictive value of the model. CONCLUSIONS: Patients with breast cancer may have changed body composition and BMD. Compared with the healthy population, the main indicators of osteoporosis in patients with breast cancer were reduced nonadipose tissue, increased risk of edema, altered fat distribution, and reduced BMD. In addition to age, duration of treatment, and duration of menopause, body composition-related indicators such as BMI and basal metabolism may be considerably associated with BMD of patients with breast cancer, suggesting that BMD status can be monitored in clinical practice by focusing on changes in the aforementioned indexes, which may provide a way to prevent preclinical osteoporosis.

Association between lumbar muscle size and bone mineral density in nonfractured postmenopausal women with and without osteoporosis.

OBJECTIVE: Estrogen deficiency in postmenopausal women is associated with bone loss and a decline in muscle mass. However, the associations between lumbar muscle size and bone mineral density (BMD) in postmenopausal women with and without osteoporosis remain unclear. The aim of this study was to investigate the associations between lumbar muscle size and BMD in nonfractured postmenopausal women with osteoporosis and those with osteopenia. METHODS: A total of 89 postmenopausal women with osteopenia (n = 53) and osteoporosis (n = 36) were retrospectively enrolled in this study from 2014 to 2022. All participants underwent lumbar magnetic resonance imaging and dual-energy absorptiometry within a month. The lean lumbar muscle sizes at different lumbar levels were quantitatively evaluated on axial T1-weighted images. The associations between lumbar muscle size and BMD were analyzed using Pearson's correlation analysis. RESULTS: The osteoporosis group had significantly smaller lean psoas muscle sizes than the osteopenia group. Based on the correlation analysis, the erector spinae and multifidus muscle sizes were significantly associated with lumbar and femoral neck BMDs in the osteoporosis group. However, no significant association was found between lean psoas muscle size and BMDs in the osteopenia group. Thus, the associations between lumbar muscle decline and bone loss differed between postmenopausal women with osteoporosis and those with osteopenia. CONCLUSIONS: The study findings suggest differences in the associations between BMD and lumbar muscle size between postmenopausal women with osteoporosis and those with osteopenia.

Establishing error bounds for internal calibration of quantitative computed tomography.

Opportunistic computed tomography (CT) scans, which can assess relevant osteoporotic bones of interest, offer a potential solution for identifying osteoporotic individuals. CT scans usually do not contain calibration phantoms, so internal calibration methods have been developed to create a voxel-specific density calibration that can be used in opportunistic CT. It remains a challenge, however, to account for potential sources of error in internal calibration, such as beam hardening or heterogeneous internal reference tissues. The purpose of this work was to introduce our internal calibration method that accounts for these variations and to estimate error bounds for the bone mineral density (BMD) measurements taken from internally calibrated scans. The error bounds are derived by incorporating a combination of a Monte Carlo simulation and standard error propagation into our previously established internal calibration method. A cohort of 138 clinical abdominal CT scans were calibrated for BMD assessment with a phantom placed in the field of view and used as the ground truth. Our modified internal calibration method provided error bounds on the same images and was tested to contain the ground truth phantom-calibrated BMD. This was repeated using 10 different internal reference tissue combinations to explore how error bounds are affected by the choice of internal tissue referents. We found that the tissue combination of air, skeletal muscle, and cortical bone yielded the most accurate BMD estimates while maintaining error bounds that were sufficiently conservative to account for sources of error such as beam hardening and heterogeneous tissue samples. The mean difference between the phantom BMD and the BMD resulting from the tissue combination of air, skeletal muscle and cortical bone was 2.12 mg/cc (0.06% BMD error) and 1.13 mg/cc (0.02 % BMD error) for the left and right femur, respectively. Providing error bounds for internal calibration provides a method to explore the influence of internal reference tissues and confidence for BMD estimates.

Abaloparatide is more potent than teriparatide in restoring bone mass and strength in type 1 diabetic male mice.

This study investigated the efficacy of the two FDA-approved bone anabolic ligands of the parathyroid hormone receptor 1 (PTH1R), teriparatide or human parathyroid hormone 1-34 (PTH) and abaloparatide (ABL), to restoring skeletal health using a preclinical murine model of streptozotocin-induced T1-DM. Intermittent daily subcutaneous injections of equal molar doses (12 pmoles/g/day) of PTH (50 ng/g/day), ABL (47.5 ng/g/day), or vehicle, were administered for 28 days to 5-month-old C57Bl/6 J male mice with established T1-DM or control (C) mice. ABL was superior to PTH in increasing or restoring bone mass in control or T1-MD mice, respectively, which was associated with superior stimulation of trabecular and periosteal bone formation, upregulation of osteoclastic/osteoblastic gene expression, and increased circulating bone remodeling markers. Only ABL corrected the reduction in ultimate load, which is a measure of bone strength, induced by T1-DM, and it also increased energy to ultimate load. In addition, bones from T1-DM mice treated with PTH or ABL exhibited increased ultimate stress, a material index, compared to T1-DM mice administered with vehicle. And both PTH and ABL prevented the increased expression of the Wnt antagonist Sost/sclerostin displayed by T1-DM mice. Further, PTH and ABL increased to a similar extent the circulating bone resorption marker CTX and the bone formation marker P1NP in T1-DM after 2 weeks of treatment; however, only ABL sustained these increases after 4 weeks of treatment. We conclude that at equal molar doses, ABL is more effective than PTH in increasing bone mass and restoring the cortical and trabecular bone lost with T1-DM, due to higher and longer-lasting increases in bone remodeling.

Post-Transplant Bone Disease in Kidney Transplant Recipients: Diagnosis and Management.

Kidney transplantation is the preferred gold standard modality of treatment for kidney failure. Bone disease after kidney transplantation is highly prevalent in patients living with a kidney transplant and is associated with high rates of hip fractures. Fractures are associated with increased healthcare costs, morbidity and mortality. Post-transplant bone disease (PTBD) includes renal osteodystrophy, osteoporosis, osteonecrosis and bone fractures. PTBD is complex as it encompasses pre-existing chronic kidney disease-mineral bone disease and compounding factors after transplantation, including the use of immunosuppression and the development of de novo bone disease. After transplantation, the persistence of secondary and tertiary hyperparathyroidism, renal osteodystrophy, relative vitamin D deficiency and high levels of fibroblast growth factor-23 contribute to post-transplant bone disease. Risk assessment includes identifying both general risk factors and kidney-specific risk factors. Diagnosis is complex as the gold standard bone biopsy with double-tetracycline labelling to diagnose the PTBD subtype is not always readily available. Therefore, alternative diagnostic tools may be used to aid its diagnosis. Both non-pharmacological and pharmacological therapy can be employed to treat PTBD. In this review, we will discuss pathophysiology, risk assessment, diagnosis and management strategies to manage PTBD after kidney transplantation.

Sex-specific association of low-renin hypertension with metabolic and musculoskeletal health in Korean older adults.

Introduction: Low-renin hypertension (LRH) accounts for approximately one-third of patients with hypertension and are more prevalent in women and the older adult population. Previous study has found a link between the renin-angiotensin-aldosterone system (RAAS) and sex hormones. However, there are insufficient data on the relationship between LRH and metabolic or musculoskeletal outcomes in older adults. Methods and materials: Among the 343 participants from a population-based cohort study conducted between May 2018 and August 2019, a total of 256 (86 men older than 50 years and 170 postmenopausal women) were included. The presence of LRH was defined as plasma renin activity (PRA) <1 ng/mL/h and systolic blood pressure (BP) ≥130 or diastolic BP ≥80 mmHg based on the 2017 ACC/AHA guidelines. Individuals with missing data, and those who had used medications that could affect PRA within the past six months were excluded. Bone mineral density (BMD), trabecular bone score (TBS), and appendicular lean mass (ALM) index were assessed using dual-energy X-ray absorptiometry; degraded TBS was defined as partially degraded to degraded levels (≤1.350). Muscle function was assessed according to the Asian Working Group for Sarcopenia guidelines. PRA was measured using radioimmunoassay. Results: The median age was 66 [61-72] years, and the body mass index (BMI) was 24.7 [23.0-26.4] kg/m2. Individuals with LRH, accounting for 34.8%, had lower diabetes mellitus; more dyslipidemia; and poorer muscle function, BMD, and TBS than those in the non-LRH group. In addition, PRA was positively correlated with C-peptide, HOMA-IR, TBS, and ALM index. After adjusting for covariates including age and BMI, LRH was negatively associated with femur neck T-score (adjusted ß = -0.30, 95% CI [-0.55 to -0.05], p = 0.021) and the presence of LRH was significantly associated with degraded TBS in women (adjusted odds ratio = 3.00, 95% CI [1.36-6.58], p = 0.006). Conclusion: Our findings suggest that LRH can influence clinical features and metabolic risk in older adults. Notably, LRH in postmenopausal women was linked to lower femur neck T-scores and degraded TBS, indicating sex-specific effects of LRH on bone health. Larger prospective studies are required to elucidate how changes in the RAAS affect metabolic and musculoskeletal outcomes in older adults.

Fully automated CT imaging biomarkers for opportunistic prediction of future hip fractures.

OBJECTIVE: Assess automated CT imaging biomarkers in patients who went on to hip fracture, compared with controls. METHODS: In this retrospective case-control study, 6926 total patients underwent initial abdominal CT over a 20-year interval at one institution. A total of 1308 patients (mean age at initial CT, 70.5 ± 12.0 years; 64.4% female) went on to hip fracture (mean time to fracture, 5.2 years); 5618 were controls (mean age 70.3 ± 12.0 years; 61.2% female; mean follow-up interval 7.6 years). Validated fully automated quantitative CT algorithms for trabecular bone attenuation (at L1), skeletal muscle attenuation (at L3), and subcutaneous adipose tissue area (SAT) (at L3) were applied to all scans. Hazard ratios (HRs) comparing highest to lowest risk quartiles and receiver operating characteristic (ROC) curve analysis including area under the curve (AUC) were derived. RESULTS: Hip fracture HRs (95% CI) were 3.18 (2.69-3.76) for low trabecular bone HU, 1.50 (1.28-1.75) for low muscle HU, and 2.18 (1.86-2.56) for low SAT. 10-year ROC AUC values for predicting hip fracture were 0.702, 0.603, and 0.603 for these CT-based biomarkers, respectively. Multivariate combinations of these biomarkers further improved predictive value; the 10-year ROC AUC combining bone/muscle/SAT was 0.733, while combining muscle/SAT was 0.686. CONCLUSION: Opportunistic use of automated CT bone, muscle, and fat measures can identify patients at higher risk for future hip fracture, regardless of the indication for CT imaging. ADVANCES IN KNOWLEDGE: CT data can be leveraged opportunistically for further patient evaluation, with early intervention as needed. These novel AI tools analyse CT data to determine a patient's future hip fracture risk.