Temporal Muscle Thickness: A Practical Approximation for Assessing Muscle Mass in Older Adults

OBJECTIVE

Ongoing research has evidenced the importance of muscle measurement in predicting adverse outcomes. Measurement of other muscles is promising in current research. This study aimed to determine the correlation between temporal muscle thickness (TMT) and appendicular lean soft tissue (ALSTI) in older adults.

DESIGN

Cross-sectional study.

SETTINGS AND PARTICIPANTS

Single cohort gathered in Gothenburg, Sweden, consisting of individuals born in 1944 (n = 1203).

METHODS

We studied 657 magnetic resonance images to measure TMT. Comparisons of TMT with dual-energy X-ray absorptiometry ALSTI (kg/m2) as a reference standard were performed. Finally, TMT associations with cognition evaluated using the Mini-Mental State Examination (MMSE), gait speed, and handgrip strength were explored with linear regressions.

RESULTS

The correlation between TMT and ALSTI was weak yet significant (r = 0.277, P < .001). TMT exhibited significant associations with MMSE (estimate = 0.168, P = .002), gait speed (estimate = 1.795, P < .001), and ALSTI (estimate = 0.508, P < .001). These associations varied when analyzed by sex. In women, TMT was significantly associated with gait speed (estimate = 1.857, P = .005) and MMSE (estimate = 0.223, P = .003). In men, TMT scores were significantly correlated with ALSTI scores (estimate = 0.571, P < .001).

CONCLUSION AND IMPLICATIONS

Repurposing head images can be an accessible alternative to detect muscle mass and ultimately detect sarcopenia. These studies have the potential to trigger interventions or further evaluation to improve the muscle and overall health of individuals. However, additional research is warranted before translating these findings into clinical practice.

Expanding access to fracture liaison services in Australia for people with minimal trauma fractures: a system dynamics modelling study

OBJECTIVES

To project how many minimal trauma fractures could be averted in Australia by expanding the number and changing the operational characteristics of fracture liaison services (FLS).

STUDY DESIGN

System dynamics modelling.

SETTING, PARTICIPANTS

People aged 50 years or more who present to hospitals with minimal trauma fractures, Australia, 2020-31.

MAIN OUTCOME MEASURES

Numbers of all minimal trauma fractures and of hip fractures averted by increasing the FLS number (from 29 to 58 or 100), patient screening rate (from 30% to 60%), and capacity for accepting new patients (from 40 to 80 per service per month), and reducing the proportion of eligible patients who do not attend FLS (from 30% to 15%); cost per fracture averted.

RESULTS

Our model projected a total of 2 441 320 minimal trauma fractures (258 680 hip fractures; 2 182 640 non-hip fractures) in people aged 50 years or older during 2020-31, including 1 211 646 second or later fractures. Increasing the FLS number to 100 averted a projected 5405 fractures (0.22%; $39 510 per fracture averted); doubling FLS capacity averted a projected 3674 fractures (0.15%; $35 835 per fracture averted). Our model projected that neither doubling the screening rate nor reducing by half the proportion of eligible patients who did not attend FLS alone would reduce the number of fractures. Increasing the FLS number to 100, the screening rate to 60%, and capacity to 80 new patients per service per month would together avert a projected 13 672 fractures (0.56%) at a cost of $42 828 per fracture averted.

CONCLUSION

Our modelling indicates that increasing the number of hospital-based FLS and changing key operational characteristics would achieve only moderate reductions in the number of minimal trauma fractures among people aged 50 years or more, and the cost would be relatively high. Alternatives to specialist-led, hospital-based FLS should be explored.

Linking sarcopenia, brain structure and cognitive performance: a large-scale UK Biobank study

Sarcopenia refers to age-related loss of muscle mass and function and is related to impaired somatic and brain health, including cognitive decline and Alzheimer's disease. However, the relationships between sarcopenia, brain structure and cognition are poorly understood. Here, we investigate the associations between sarcopenic traits, brain structure and cognitive performance. We included 33 709 UK Biobank participants (54.2% female; age range 44-82 years) with structural and diffusion magnetic resonance imaging, thigh muscle fat infiltration (n = 30 561) from whole-body magnetic resonance imaging (muscle quality indicator) and general cognitive performance as indicated by the first principal component of a principal component analysis across multiple cognitive tests (n = 22 530). Of these, 1703 participants qualified for probable sarcopenia based on low handgrip strength, and we assigned the remaining 32 006 participants to the non-sarcopenia group. We used multiple linear regression to test how sarcopenic traits (probable sarcopenia versus non-sarcopenia and percentage of thigh muscle fat infiltration) relate to cognitive performance and brain structure (cortical thickness and area, white matter fractional anisotropy and deep and lower brain volumes). Next, we used structural equation modelling to test whether brain structure mediated the association between sarcopenic and cognitive traits. We adjusted all statistical analyses for confounders. We show that sarcopenic traits (probable sarcopenia versus non-sarcopenia and muscle fat infiltration) are significantly associated with lower cognitive performance and various brain magnetic resonance imaging measures. In probable sarcopenia, for the included brain regions, we observed widespread significant lower white matter fractional anisotropy (77.1% of tracts), predominantly lower regional brain volumes (61.3% of volumes) and thinner cortical thickness (37.9% of parcellations), with |r| effect sizes in (0.02, 0.06) and P-values in (0.0002, 4.2e-29). In contrast, we observed significant associations between higher muscle fat infiltration and widespread thinner cortical thickness (76.5% of parcellations), lower white matter fractional anisotropy (62.5% of tracts) and predominantly lower brain volumes (35.5% of volumes), with |r| effect sizes in (0.02, 0.07) and P-values in (0.0002, 1.9e-31). The regions showing the most significant effect sizes across the cortex, white matter and volumes were of the sensorimotor system. Structural equation modelling analysis revealed that sensorimotor brain regions mediate the link between sarcopenic and cognitive traits [probable sarcopenia: P-values in (0.0001, 1.0e-11); muscle fat infiltration: P-values in (7.7e-05, 1.7e-12)]. Our findings show significant associations between sarcopenic traits, brain structure and cognitive performance in a middle-aged and older adult population. Mediation analyses suggest that regional brain structure mediates the association between sarcopenic and cognitive traits, with potential implications for dementia development and prevention.

The Conceptual Definition of Sarcopenia: Delphi Consensus from the Global Leadership Initiative in Sarcopenia (GLIS)

IMPORTANCE

Sarcopenia, the age-related loss of muscle mass and strength/function, is an important clinical condition. However, no international consensus on the definition exists.

OBJECTIVE

The Global Leadership Initiative in Sarcopenia (GLIS) aimed to address this by establishing the global conceptual definition of sarcopenia.

DESIGN

The GLIS steering committee was formed in 2019-21 with representatives from all relevant scientific societies worldwide. During this time, the steering committee developed a set of statements on the topic and invited members from these societies to participate in a two-phase International Delphi Study. Between 2022 and 2023, participants ranked their agreement with a set of statements using an online survey tool (SurveyMonkey). Statements were categorised based on predefined thresholds: strong agreement (>80%), moderate agreement (70-80%) and low agreement (<70%). Statements with strong agreement were accepted, statements with low agreement were rejected and those with moderate agreement were reintroduced until consensus was reached.

RESULTS

107 participants (mean age: 54 ± 12 years [1 missing age], 64% men) from 29 countries across 7 continents/regions completed the Delphi survey. Twenty statements were found to have a strong agreement. These included; 6 statements on 'general aspects of sarcopenia' (strongest agreement: the prevalence of sarcopenia increases with age (98.3%)), 3 statements on 'components of sarcopenia' (muscle mass (89.4%), muscle strength (93.1%) and muscle-specific strength (80.8%) should all be a part of the conceptual definition of sarcopenia)) and 11 statements on 'outcomes of sarcopenia' (strongest agreement: sarcopenia increases the risk of impaired physical performance (97.9%)). A key finding of the Delphi survey was that muscle mass, muscle strength and muscle-specific strength were all accepted as 'components of sarcopenia', whereas impaired physical performance was accepted as an 'outcome' rather than a 'component' of sarcopenia.

CONCLUSION AND RELEVANCE

The GLIS has created the first global conceptual definition of sarcopenia, which will now serve to develop an operational definition for clinical and research settings.

Fat as a Friend or Foe of the Bone

PURPOSE OF REVIEW

The objective of this review is to summarize the literature on the prevalence and diagnosis of obesity and its metabolic profile, including bone metabolism, focusing on the main inflammatory and turnover bone mediators that better characterize metabolically healthy obesity phenotype, and to summarize the therapeutic interventions for obesity with their effects on bone health.

RECENT FINDINGS

Osteoporosis and fracture risk not only increase with age and menopause but also with metabolic diseases, such as diabetes mellitus. Thus, patients with high BMI may have a higher bone fragility and fracture risk. However, some obese individuals with healthy metabolic profiles seem to be less at risk of bone fracture. Obesity has become an alarming disease with growing prevalence and multiple metabolic comorbidities, resulting in a significant burden on healthcare and increased mortality. The imbalance between increased food ingestion and decreased energy expenditure leads to pathological adipose tissue distribution and function, with increased secretion of proinflammatory markers and harmful consequences for body tissues, including bone tissue. However, some obese individuals seem to have a healthy metabolic profile and may not develop cardiometabolic disease during their lives. This healthy metabolic profile also benefits bone turnover and is associated with lower fracture risk.

Nutrient Intake and Its Association with Appendicular Total Lean Mass and Muscle Function and Strength in Older Adults: A Population-Based Study

Treatment options for sarcopenia are currently limited, and primarily rely on two main therapeutic approaches: resistance-based physical activity and dietary interventions. However, details about specific nutrients in the diet or supplementation are unclear. We aim to investigate the relationship between nutrient intake and lean mass, function, and strength. Data were derived from the Gothenburg H70 birth cohort study in Sweden, including 719,70-year-olds born in 1944 (54.1% females). For independent variables, the diet history method (face-to-face interviews) was used to estimate habitual food intake during the preceding three months. Dependent variables were gait speed (muscle performance), hand grip strength (muscle strength), and the appendicular lean soft tissue index (ALSTI). Linear regression analyses were performed to analyze the relationship between the dependent variables and each of the covariates. Several nutrients were positively associated with ALSTI, such as polyunsaturated fatty acids (DHA, EPA), selenium, zinc, riboflavin, niacin equivalent, vitamin B12, vitamin D, iron, and protein. After correction for multiple comparisons, there were no remaining correlations with handgrip and gait speed. Findings of positive correlations for some nutrients with lean mass suggest a role for these nutrients in maintaining muscle volume. These results can be used to inform clinical trials to expand the preventive strategies and treatment options for individuals at risk of muscle loss and sarcopenia.

Exploring new balance and gait factors that are associated with osteosarcopenia in patients with a previous fall and/or fracture history

Osteosarcopenic individuals have poor muscle function and increased bone fragility, which results in a severe detriment to health outcomes. Hence, there is a necessity to discover easily accessible factors associated with osteosarcopenia to develop timely interventions. This study aimed to determine new sensitive balance and/or gait variables that are associated with osteosarcopenia in a population of older people with a history of falls and/or fractures. In a cross-sectional cohort study, 306 men and women aged ≥65 years completed a series of questionnaires, clinical assessments and muscle strength and function tests. Subsequently, participants were separated into osteopenia, osteoporosis and osteosarcopenia, groups for comparison and further analysis. Osteosarcopenia performed worse than osteopenia and osteoporosis in grip strength, gait speed, physical function scores and in multiple gait and balance indices (p<0.001). During posturography testing, there were larger elliptical areas with eyes open (p = 0.003), and eyes closed (p = 0.043) and increased sway velocity on a firm platform (p = 0.007) in the osteosarcopenia group, compared to osteoporosis. Limits of stability and eyes open ellipse area significantly contributed to the multivariable model (p = 0.029 and p = 0.038, respectively), suggesting that these balance parameters, along with grip strength, may be useful in identifying older adults with osteosarcopenia from those with only osteopenia/osteoporosis. Older adults with osteosarcopenia and a history of falls and/or fractures demonstrated inferior strength, function, and gait characteristics. This study identified indices of balance that were sensitive discriminators for osteosarcopenia and could be easily implemented into routine assessment.

Using magnetic resonance imaging to measure head muscles: An innovative method to opportunistically determine muscle mass and detect sarcopenia

BACKGROUND

Sarcopenia is associated with multiple adverse outcomes. Traditional methods to determine low muscle mass for the diagnosis of sarcopenia are mainly based on dual-energy X-ray absorptiometry (DXA), whole-body magnetic resonance imaging (MRI) and bioelectrical impedance analysis. These tests are not always available and are rather time consuming and expensive. However, many brain and head diseases require a head MRI. In this study, we aim to provide a more accessible way to detect sarcopenia by comparing the traditional method of DXA lean mass estimation versus the tongue and masseter muscle mass assessed in a standard brain MRI.

METHODS

The H70 study is a longitudinal study of older people living in Gothenburg, Sweden. In this cross-sectional analysis, from 1203 participants aged 70 years at baseline, we included 495 with clinical data and MRI images available. We used the appendicular lean soft tissue index (ALSTI) in DXA images as our reference measure of lean mass. Images from the masseter and tongue were analysed and segmented using 3D Slicer. For the statistical analysis, the Spearman correlation coefficient was used, and concordance was estimated with the Kappa coefficient.

RESULTS

The final sample consisted of 495 participants, of which 52.3% were females. We found a significant correlation coefficient between both tongue (0.26) and masseter (0.33) with ALSTI (P < 0.001). The sarcopenia prevalence confirmed using the alternative muscle measure in MRI was calculated using the ALSTI (tongue = 2.0%, masseter = 2.2%, ALSTI = 2.4%). Concordance between sarcopenia with masseter and tongue versus sarcopenia with ALSTI as reference has a Kappa of 0.989 (P < 0.001) for masseter and a Kappa of 1 for the tongue muscle (P < 0.001). Comorbidities evaluated with the Cumulative Illness Rating Scale were significantly associated with all the muscle measurements: ALSTI (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.07-1.26, P < 0.001), masseter (OR 1.16, 95% CI 1.07-1.26, P < 0.001) and tongue (OR 1.13, 95% CI 1.04-1.22, P = 0.002); the higher the comorbidities, the higher the probability of having abnormal muscle mass.

CONCLUSIONS

ALSTI was significantly correlated with tongue and masseter muscle mass. When performing the sarcopenia diagnostic algorithm, the prevalence of sarcopenia calculated with head muscles did not differ from sarcopenia calculated using DXA, and almost all participants were correctly classified using both methods.

Does physical activity moderate the association between shorter leukocyte telomere length and incident coronary heart disease? Data from 54,180 UK Biobank participants

Telomere shortening is a biological aging hallmark. The effect of short telomere length may be targeted by increased physical activity to reduce the risk of multiple aging-related diseases, including coronary heart disease (CHD). The objective was to assess the moderation effect of accelerometer-based physical activity (aPA) on the association between shorter leukocyte telomere length (LTL) relatively in the population sample and incident CHD. Data were from the UK Biobank participants with well-calibrated accelerometer data for at least 6.5 days (n = 54,180). Relative mean LTL at baseline (5-6 years prior to aPA assessment) was measured in T/S ratio, using a multiplex quantitative polymerase chain reaction (qPCR) technology, by comparing the amount of the telomere amplification product (T) to that of a single-copy gene (S). aPA measures included total number of events (at least 10-s continued physical activity > 32 milligravities [mg]), total volume, mean duration, mean intensity, and peak intensity of all events. LTL, aPA measures, and their interactions were associated with incident CHD (mean follow-up 6.8 years) using Cox proportional hazards models adjusting for covariates. Longer LTL (relative to the sample distribution) was associated with reduced incidence of CHD (adjusted hazard ratio [aHR] = 0.94 per standard deviation [SD] increase in LTL, [95% CI, 0.90 to 0.99], P = .010). Incidence of CHD was reduced by higher total volume of aPA (aHR = 0.82 per SD increase in LTL, [95% CI, 0.71 to 0.95], P = .010) but increased by higher total number of events (aHR = 1.11 per SD increase in LTL, [95% CI, 1.02 to 1.21], P = .020) after controlling for other aPA measures and covariates. However, none of the interactions between LTL and aPA measures was statistically significant (P = .171).

Challenges in Delivering Effective Care for Older Persons with Fragility Fractures

Fragility fractures occur because of low-impact trauma or even spontaneously in individuals with osteoporosis. Caring for older persons with fragility fractures can present several challenges due to the unique needs and vulnerabilities of this population. Older individuals commonly have multiple medical conditions, such as osteoporosis, arthritis, cardiovascular diseases, and diabetes. These comorbidities can complicate fracture management and increase the risk of complications. Fracture repair through surgery may be more complex in older patients due to poor bone quality, decreased tissue elasticity, and higher chances of anesthesia complications. In addition, mobility and functional limitations post-fracture are highly prevalent in this population, affecting their independence and increasing their risk of institutionalization. Addressing these challenges requires a multidisciplinary approach involving orthopedic surgeons, geriatricians, physical and rehabilitation physicians, physiotherapists, occupational therapists, dieticians, social workers, and caregivers. Preventive measures, such as fall prevention strategies and osteoporosis management, can also play a vital role in reducing the incidence of fragility fractures in older persons.

Exercise as a Therapeutic Tool in Age-Related Frailty and Cardiovascular Disease: Challenges and Strategies

Understanding the link between heart disease and frailty in older adults is crucial. Although medical progress has extended life, it has not fully addressed the decline in function and quality of life in frail older people. Frailty is a state of vulnerability to health stressors that needs comprehensive solutions. Its assessment within health care, especially in cardiology, is important owing to its association with worse clinical outcomes. Recent evidence and guidelines suggest that the prescription of a comprehensive exercise regimen, tailored to progressively include strength, balance, mobility, and endurance training improves adherence, functionality, and health-related quality of life, in both acute and chronic cardiovascular diseases. In addition, exercise is a vital tool that improves function, targets frailty, and holistically affects the body's systems. Still, many frail people do not exercise enough, and when they do, they usually do not follow an appropriate plan tailored for better functional outcomes. Overcoming barriers and limitations in exercise enrollment and adherence through strategies such as automated cardiac rehabilitation referral, patient education, and eHealth tools can notably improve clinical outcomes.

The Interconnection Between Muscle and Bone: A Common Clinical Management Pathway

Often observed with aging, the loss of skeletal muscle (sarcopenia) and bone (osteoporosis) mass, strength, and quality, is associated with reduced physical function contributing to falls and fractures. Such events can lead to a loss of independence and poorer quality of life. Physical inactivity (mechanical unloading), especially in older adults, has detrimental effects on the mass and quality of bone as well as muscle, while increases in activity (mechanical loading) have positive effects. Emerging evidence suggests that the relationship between bone and muscle is driven, at least in part, by bone-muscle crosstalk. Bone and muscle are closely linked anatomically, mechanically, and biochemically, and both have the capacity to function with paracrine and endocrine-like action. However, the exact mechanisms involved in this crosstalk remain only partially explored. Given older adults with lower bone mass are more likely to present with impaired muscle function, and vice versa, strategies capable of targeting both bone and muscle are critical. Exercise is the primary evidence-based prevention strategy capable of simultaneously improving muscle and bone health. Unfortunately, holistic treatment plans including exercise in conjunction with other allied health services to prevent or treat musculoskeletal disease remain underutilized. With a focus on sarcopenia and osteoporosis, the aim of this review is to (i) briefly describe the mechanical and biochemical interactions between bone and muscle; (ii) provide a summary of therapeutic strategies, specifically exercise, nutrition and pharmacological approaches; and (iii) highlight a holistic clinical pathway for the assessment and management of sarcopenia and osteoporosis.

Assessment of Osteogenic Exercise Efficacy via Bone Turnover Markers in Premenopausal Women: A Randomized Controlled Trial

Assessing bone's response to physical activity interventions is challenging. This randomized controlled trial investigates if changes in bone turnover markers can offer an early evaluation of a physical activity intervention's effectiveness in improving bone mineral density (BMD) in premenopausal women. Participants in the intervention group (n = 27, with 24 completing the trial) were instructed to walk at least 10,000 steps every day on a brisk walk and to execute 60 jumps daily, each surpassing 4g of acceleration, using an accelerometer-based wearable device. Meanwhile, the control group (n = 26, with 18 completing the trial) continued with their usual lifestyle. Bone turnover markers, comprising of C-terminal telopeptide of Type I collagen, procollagen Type 1 N-terminal propeptide, and total osteocalcin (carboxylated and undercarboxylated) were measured at baseline and midway through the intervention (3 months). Dual-energy X-ray absorptiometry scans of the hip and lumbar spine were conducted at baseline and the end of the intervention (6 months) to estimate BMD. Analysis of covariance exhibited significant differences between groups in procollagen Type 1 N-terminal propeptide (-6.74 μg/L, p = .023) and C-terminal telopeptide of Type I collagen (-83 ng/L, p = .043) after 3 months, and in femoral neck BMD (+0.024 g/cm2, p = .016), total hip BMD (+0.036 g/cm2, p = .004), and lumbar spine BMD (+0.026 g/cm2, p = .020) after 6 months. A significant correlation (r = -.73; p < .001) was detected between reductions in C-terminal telopeptide of Type I collagen and increases in femoral neck BMD. In conclusion, this intervention improved BMD in premenopausal women, with bone turnover markers potentially useful for early intervention assessment, though further research is needed.

Associations between Osteosarcopenia and Falls, Fractures, and Frailty in Older Adults: Results From the Canadian Longitudinal Study on Aging (CLSA)

OBJECTIVE

To explore if older adults with osteosarcopenia are at a greater risk of falls, fractures, frailty, and worsening life satisfaction and activities of daily living (ADL) compared to those with normal bone mineral density (BMD) and without sarcopenia.

DESIGN

The baseline and 3-year follow-up of a longitudinal study.

SETTING AND PARTICIPANTS

Community-dwelling people aged 65 years or older in Canada.

METHODS

Caucasian participants 65 years or older that completed the Canadian Longitudinal Study on Aging (CLSA) 2015 baseline interview, physical measurements and 3-year follow-up were included. Osteopenia/osteoporosis was defined as BMD T score below -1 SD according to the World Health Organization, and sarcopenia was defined as low grip strength and/or low gait speed according to the Sarcopenia Definition Outcomes Consortium. Osteosarcopenia was defined as the coexistence of osteopenia/osteoporosis and sarcopenia. Self-reported incident falls and fractures in the last 12 months before the 3-year follow-up were measured. Frailty was assessed through the Rockwood Frailty Index (FI); life satisfaction through the Satisfaction With Life Scale (SWLS); and ADL through the Older American Resources and Services modules. Multivariable logistic and linear regression, including subgroup analyses by sex, were conducted.

RESULTS

The sample of 8888 participants (49.1% females) had a mean age (SD) of 72.7 (5.6) years. At baseline, neither osteopenia/osteoporosis nor sarcopenia (reference group) was present in 30.1%, sarcopenia only in 18.4%, osteopenia/osteoporosis only in 29.2%, and osteosarcopenia in 22.3%. Osteosarcopenia was significantly associated with incident falls and fractures in males [adjusted odds ratio (aOR), 1.90, 95% CI 1.15, 3.14, and aOR 2.60, 95% CI 1.14, 5.91, respectively] compared to males without osteopenia/osteoporosis or sarcopenia. Participants with osteosarcopenia had worsening ADL of 0.110 (estimated β coefficient 0.110, 95% CI 0.029, 0.192) and a decrease in their SWLS by 0.660 (estimated β coefficient -0.660, 95% CI -1.133, -0.187), compared to those without. Osteosarcopenia was not associated with frailty for both males and females.

CONCLUSIONS AND IMPLICATIONS

Osteosarcopenia was associated with self-reported incident falls and fractures in males and worse life satisfaction and ADL for all participants. Assessing and identifying osteosarcopenia is essential for preventing falls and fractures. Furthermore, it improves life satisfaction and ADL.

Differential responses to aging amongst the transcriptome and proteome of mesenchymal progenitor populations

The biological aging of mesenchymal stem cells is proposed to contribute to the development of a range of musculoskeletal and systemic diseases associated with older adults, such as osteoporosis, sarcopenia, and frailty. Despite this, little is understood about the specific mechanisms which drive this stem cell exhaustion, with most studies evaluating indirect effects of other aging changes, such as DNA damage, senescence, and inflammaging. In this study, we assess the transcriptomic and proteomic changes in three different populations of mesenchymal progenitor cells from older (50-70 years) and younger (20-40 years) individuals to uncover potential mechanisms driving stem cell exhaustion in mesenchymal tissues. To do this, we harvested primary bone marrow mesenchymal stem and progenitor cells (MPCs), circulating osteoprogenitors (COP), and adipose-derived stem cells (ADSCs) from younger and older donors, with an equal number of samples from males and females. These samples underwent RNA sequencing and label-free proteomic analysis, comparing the younger samples to the older ones. There was a distinct transcriptomic phenotype associated with the pooled older stem cells, indicative of suppressed proliferation and differentiation; however, there was no consistent change in the proteome of the cells. Older MPCs had a distinct phenotype in both the transcriptome and proteome, again consistent with altered differentiation and proliferation, but also a pro-inflammatory immune shift in older adults. COP cells showed a strong transcriptomic shift to pro-inflammatory signaling but no consistent proteomic phenotype. Similarly, ADSCs displayed transcriptomic shift in physiologies associated with cell migration, adherence, and immune activation, but no consistent proteomic change with age. These results show that there are underlying transcriptomic changes with stem cell aging that likely contribute to a decline in tissue regeneration; however, contextual factors such as the microenvironment and general health status also have a strong role in this.

Predicting Slow Walking Speed From a Pooled Cohort Analysis: Sarcopenia Definitions, Agreement, and Prevalence in Australia and New Zealand

BACKGROUND

Recent operational definitions of sarcopenia have not been replicated and compared in Australia and New Zealand (ANZ) populations. We aimed to identify sarcopenia measures that discriminate ANZ adults with slow walking speed (<0.8 m/s) and determine the agreement between the Sarcopenia Definitions and Outcomes Consortium (SDOC) and revised European Working Group for Sarcopenia in Older People (EWGSOP2) operational definitions of sarcopenia.

METHODS

Eight studies comprising 8 100 ANZ community-dwelling adults (mean age ± standard deviation, 62.0 ± 14.4 years) with walking speed, grip strength (GR), and lean mass data were combined. Replicating the SDOC methodology, 15 candidate variables were included in sex-stratified classification and regression tree models and receiver operating characteristic curves on a pooled cohort with complete data to identify variables and cut points discriminating slow walking speed (<0.8 m/s). Agreement and prevalence estimates were compared using Cohen's Kappa (CK).

RESULTS

Receiver operating characteristic curves identified GR as the strongest variable for discriminating slow from normal walking speed in women (GR <20.50 kg, area under curve [AUC] = 0.68) and men (GR <31.05 kg, AUC = 0.64). Near-perfect agreement was found between the derived ANZ cut points and SDOC cut points (CK 0.8-1.0). Sarcopenia prevalence ranged from 1.5% (EWGSOP2) to 37.2% (SDOC) in women and 1.0% (EWGSOP2) to 9.1% (SDOC) in men, with no agreement (CK <0.2) between EWGSOP2 and SDOC.

CONCLUSIONS

Grip strength is the primary discriminating characteristic for slow walking speed in ANZ women and men, consistent with findings from the SDOC. Sarcopenia Definitions and Outcomes Consortium and EWGSOP2 definitions showed no agreement suggesting these proposed definitions measure different characteristics and identify people with sarcopenia differently.

Classification of Fracture Risk in Fallers Using Dual-Energy X-Ray Absorptiometry (DXA) Images and Deep Learning-Based Feature Extraction

Dual-energy X-ray absorptiometry (DXA) scans are one of the most frequently used imaging techniques for calculating bone mineral density, yet calculating fracture risk using DXA image features is rarely performed. The objective of this study was to combine deep neural networks, together with DXA images and patient clinical information, to evaluate fracture risk in a cohort of adults with at least one known fall and age-matched healthy controls. DXA images of the entire body as, well as isolated images of the hip, forearm, and spine (1488 total), were obtained from 478 fallers and 48 non-faller controls. A modeling pipeline was developed for fracture risk prediction using the DXA images and clinical data. First, self-supervised pretraining of feature extractors was performed using a small vision transformer (ViT-S) and a convolutional neural network model (VGG-16 and Resnet-50). After pretraining, the feature extractors were then paired with a multilayer perceptron model, which was used for fracture risk classification. Classification was achieved with an average area under the receiver-operating characteristic curve (AUROC) score of 74.3%. This study demonstrates ViT-S as a promising neural network technique for fracture risk classification using DXA scans. The findings have future application as a fracture risk screening tool for older adults at risk of falls. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Circulating Osteoprogenitor Cells Have a Mixed Immune and Mesenchymal Progenitor Function in Humans

BACKGROUND

Circulating osteoprogenitors (COP) are a population of cells in the peripheral circulation that possess functional and phenotypical characteristics of multipotent stromal cells (MSCs). This population has a solid potential to become an abundant, accessible, and replenishable source of MSCs with multiple potential clinical applications. However, a comprehensive functional characterization of COP cells is still required to test and fully develop their use in clinical settings.

METHODS

This study characterized COP cells by comparing them to bone marrow-derived MSCs (BM-MSCs) and adipose-derived MSCs (ASCs) through detailed transcriptomic and proteomic analyses.

RESULTS

We demonstrate that COP cells have a distinct gene and protein expression pattern with a significantly stronger immune footprint, likely owing to their hematopoietic lineage. In addition, regarding progenitor cell differentiation and proliferation pathways, COP cells have a similar expression pattern to BM-MSCs and ASCs.

CONCLUSION

COP cells are a unique but functionally similar population to BM-MSCs and ASCs, sharing their proliferation and differentiation capacity, thus presenting an accessible source of MSCs with strong potential for translational regenerative medicine strategies.

Mortality, falls and slow walking speed are predicted by different muscle strength and physical performance measures in women and men

BACKGROUND

Different measures of muscle strength, physical performance and body size/composition are used in various sarcopenia definitions. This study investigated which baseline measures best predict incident mortality and falls, and prevalent slow walking speed in older women and men.

MATERIALS AND METHODS

Data for 899 women (mean age±standard deviation, 68.7 ± 4.3 years) and 497 men (69.4 ± 3.9 years) from the Dubbo Osteoporosis Epidemiology Study 2, comprising sixty variables for muscle strength (quadriceps strength), physical performance (walking speed, timed up and go (TUG) test, sit to stand (STS) test), body size (weight, height, body mass index) and body composition (lean mass, body fat) were included. Sex-stratified Classification and Regression Tree (CART) analyses calculated baseline variable accuracy for predicting incident mortality and falls, and prevalent slow walking speed (<0.8 m/s).

RESULTS

Over 14.5 years, 103/899 (11.5%) women and 96/497 (19.3%) men died, 345/899 (38.4%) women and 172/497 (34.6%) men had ≥1 fall, and 304/860 (35.3%) women and 172/461 (31.7%) had baseline slow walking speed (<0.8 m/s). CART models identified age and walking speed adjusted for height as the most important predictors for mortality in women, and quadriceps strength (with adjustments) as the most important predictor for mortality in men. In both sexes, STS (with adjustments) was the most important predictor for incident falls, and TUG test was the most important predictor for prevalent slow walking speed. Body composition measures were not important predictors for any outcome.

CONCLUSIONS

Muscle strength and physical performance variables and cut points predict falls and mortality differently in women and men, suggesting targeted sex-specific application of selected measures may improve outcome prediction in older adults.

The Impact of Interventional Weight Loss on Bone Marrow Adipose Tissue in People Living with Obesity and Its Connection to Bone Metabolism

This review focuses on providing physicians with insights into the complex relationship between bone marrow adipose tissue (BMAT) and bone health, in the context of weight loss through caloric restriction or metabolic and bariatric surgery (MBS), in people living with obesity (PwO). We summarize the complex relationship between BMAT and bone health, provide an overview of noninvasive imaging techniques to quantify human BMAT, and discuss clinical studies measuring BMAT in PwO before and after weight loss. The relationship between BMAT and bone is subject to variations based on factors such as age, sex, menopausal status, skeletal sites, nutritional status, and metabolic conditions. The Bone Marrow Adiposity Society (BMAS) recommends standardizing imaging protocols to increase comparability across studies and sites, they have identified both water-fat imaging (WFI) and spectroscopy (1H-MRS) as accepted standards for in vivo quantification of BMAT. Clinical studies measuring BMAT in PwO are limited and have shown contradictory results. However, BMAT tends to be higher in patients with the highest visceral adiposity, and inverse associations between BMAT and bone mineral density (BMD) have been consistently found in PwO. Furthermore, BMAT levels tend to decrease after caloric restriction-induced weight loss. Although weight loss was associated with overall fat loss, a reduction in BMAT did not always follow the changes in fat volume in other tissues. The effects of MBS on BMAT are not consistent among the studies, which is at least partly related to the differences in the study population, skeletal site, and duration of the follow-up. Overall, gastric bypass appears to decrease BMAT, particularly in patients with diabetes and postmenopausal women, whereas sleeve gastrectomy appears to increase BMAT. More research is necessary to evaluate changes in BMAT and its connection to bone metabolism, either in PwO or in cases of weight loss through caloric restriction or MBS, to better understand the role of BMAT in this context and determine the local or systemic factors involved.

Interactions Between HR-pQCT Bone Density and D3 Cr Muscle Mass (or HR-pQCT Bone Structure and HR-pQCT Muscle Density) in Predicting Fractures: The Osteoporotic Fractures in Men Study

We examined if an interaction exists between bone and muscle in predicting fractures in older men. Prospective data from the Osteoporotic Fractures in Men study was used to build Cox proportional hazards models. Predictors included HR-pQCT total volumetric BMD (Tt.BMD), trabecular BMD (Tb.BMD), cortical BMD (Ct.BMD) and cortical area (Ct.Ar) at distal radius/tibia, HR-pQCT muscle volume and density (diaphyseal tibia), D3 -creatine dilution (D3 Cr) muscle mass, and grip strength and leg force, analyzed as continuous variables and as quartiles. Incident fractures were self-reported every 4 months via questionnaires and centrally adjudicated by physician review of radiology reports. Potential confounders (demographics, comorbidities, lifestyle factors, etc.) were considered. A total of 1353 men (mean age 84.2 ± 4.0 years, 92.7% white) were followed for 6.03 ± 2.11 years. In the unadjusted (continuous) model, there were no interactions (p > 0.05) between any muscle variable (D3 Cr muscle mass, muscle volume, muscle density, grip strength or leg force) and Tt.BMD at distal radius/tibia for fractures (all: n = 182-302; nonvertebral: n = 149-254; vertebral: n = 27-45). No consistent interactions were observed when interchanging Tt.BMD for Tb.BMD/Ct.BMD or for Ct.Ar (bone structure) at the distal radius/tibia in the unadjusted (continuous) models. Compared with men in quartiles (Q) 2-4 of D3 Cr muscle mass and Q2-4 of distal tibia Tt.BMD, men in Q1 of both had increased risk for all fractures (hazard ratio (HR) = 2.00; 95% confidence interval [CI] 1.24-3.23, p = 0.005) and nonvertebral fractures (HR = 2.10; 95% CI 1.25-3.52, p < 0.001) in the multivariable-adjusted model. Confidence intervals overlapped (p > 0.05) when visually inspecting other quartile groups in the multivariable-adjusted model. In this prospective cohort study of older men, there was no consistent interactions between bone and muscle variables on fracture risk. Larger sample sizes and longer follow-up may be needed to clarify if there is an interaction between bone and muscle on fracture risk in men. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Safety and Efficacy of Testosterone Therapy on Musculoskeletal Health and Clinical Outcomes in Men: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials

OBJECTIVE

Age-related declines in muscle and bone, alongside a shift toward greater adiposity, contribute to falls and fracture risk. Testosterone is osteogenic, myogenic, and catabolic to fat. As such, we examined the effects of testosterone therapy on musculoskeletal health and clinical outcomes in men.

METHODS

Electronic databases (Medline, Embase, Web of Science, Central) were systematically searched for randomized controlled trials (RCTs) reporting on the effects of testosterone therapy versus placebo on any primary outcome (bone density, muscle mass, fat mass, muscle strength/physical performance) or secondary outcome (falls, fractures, disability, adverse events) in men (≥18 years). A random effects meta-regression examined the effects of testosterone on prespecified outcomes.

RESULTS

One thousand seven hundred twenty-eight men across 16 RCTs were included (mean age: 77.1 ± 7.6 years). Baseline mean serum testosterone ranged from 7.5 ± 0.3 to 18.9 ± 1.2 nmol/L. Compared to placebo, 6 months of testosterone therapy increased hip bone density and total lean mass, but effects for handgrip and total fat mass did not reach statistical significance. No significant effects of testosterone therapy on musculoskeletal outcomes were evident at 12 months. The limited number of RCTs reporting on adverse events/clinical outcomes, and the low incidence of these events across RCTs, prohibited statistical comparisons.

CONCLUSION

After 6 months, testosterone effectively increases hip bone density and total lean mass in men, but its effects are unclear for lumbar spine bone density and handgrip strength. Further, RCTs are needed to clarify the safety and efficacy of testosterone on musculoskeletal health and clinical outcomes.

Fourier-Transform Infrared Spectroscopy as a Screening Tool for Osteosarcopenia in Community-Dwelling Older Women

Osteosarcopenia is a complex geriatric syndrome characterized by the presence of both sarcopenia and osteopenia/osteoporosis. This condition increases rates of disability, falls, fractures, mortality, and mobility impairments in older adults. The purpose of this study was to analyze the Fourier-transform infrared (FTIR) spectroscopy diagnostic power for osteosarcopenia in community-dwelling older women (n = 64; 32 osteosarcopenic and 32 non-osteosarcopenia). FTIR is a fast and reproducible technique highly sensitive to biological tissues, and a mathematical model was created using multivariate classification techniques that denoted the graphic spectra of the molecular groups. Genetic algorithm and support vector machine regression (GA-SVM) was the most feasible model, achieving 80.0% of accuracy. GA-SVM identified 15 wave numbers responsible for class differentiation, in which several amino acids (responsible for the proper activation of the mammalian target of rapamycin) and hydroxyapatite (an inorganic bone component) were observed. Imaging tests and low availability of instruments that allow the observation of osteosarcopenia involve high health costs for patients and restrictive indications. Therefore, FTIR can be used to diagnose osteosarcopenia due to its efficiency and low cost and to enable early detection in geriatric services, contributing to advances in science and technology that are potential "conventional" methods in the future.

Safer medicines To reduce falls and refractures for OsteoPorosis (#STOP): a study protocol for a randomised controlled trial of medical specialist-initiated pharmacist-led medication management reviews in primary care

INTRODUCTION

Minimal trauma fractures (MTFs) often occur in older patients with osteoporosis and may be precipitated by falls risk-increasing drugs. One category of falls risk-increasing drugs of concern are those with sedative/anticholinergic properties. Collaborative medication management services such as Australia's Home Medicine Review (HMR) can reduce patients' intake of sedative/anticholinergics and improve continuity of care. This paper describes a protocol for an randomised controlled trial to determine the efficacy of an HMR service for patients who have sustained MTF.

METHOD AND ANALYSIS

Eligible participants are as follows: ≥65 years of age, using ≥5 medicines including at least one falls risk-increasing drug, who have sustained an MTF and under treatment in one of eight Osteoporosis Refracture Prevention clinics in Australia. Consenting participants will be randomised to control (standard care) or intervention groups. For the intervention group, medical specialists will refer to a pharmacist for HMR focused on reducing falls risk predominately through making recommendations to reduce falls risk medicines, and adherence to antiosteoporosis medicines. Twelve months from treatment allocation, comparisons between groups will be made. The main outcome measure is participants' cumulative exposure to sedative and anticholinergics, using the Drug Burden Index. Secondary outcomes include medication adherence, emergency department visits, hospitalisations, falls and mortality. Economic evaluation will compare the intervention strategy with standard care.

ETHICS AND DISSEMINATION

Approval was obtained via the New South Wales Research Ethics and Governance Information System (approval number: 2021/ETH12003) with site-specific approvals granted through Human Research Ethics Committees for each research site. Study outcomes will be published in peer-reviewed journals. It will provide robust insight into effectiveness of a pharmacist-based intervention on medicine-related falls risk for patients with osteoporosis. We anticipate that this study will take 2 years to fully accrue including follow-up.

TRIAL REGISTRATION NUMBER

ACTRN12622000261718.

The Role of the Kynurenine Pathway in the Pathophysiology of Frailty, Sarcopenia, and Osteoporosis

Tryptophan is an essential nutrient required to generate vitamin B3 (niacin), which is mainly involved in energy metabolism and DNA production. Alterations in tryptophan metabolism could have significant effects on aging and musculoskeletal health. The kynurenine pathway, essential in tryptophan catabolism, is modulated by inflammatory factors that are increased in older persons, a process known as inflammaging. Osteoporosis, sarcopenia, osteosarcopenia, and frailty have also been linked with chronically increased levels of inflammatory factors. Due to the disruption of the kynurenine pathway by chronic inflammation and/or changes in the gut microbiota, serum levels of toxic metabolites are increased and are associated with the pathophysiology of those conditions. In contrast, anabolic products of this pathway, such as picolinic acid, have demonstrated a positive effect on skeletal muscle and bone. In addition, physical activity can modulate this pathway by promoting the secretion of anabolic kynurenines. According to the evidence collected, kynurenines could have a promising role as biomarkers for osteoporosis sarcopenia, osteosarcopenia, and frailty in older persons. In addition, some of these metabolites could become important targets for developing new pharmacological treatments for these conditions.

Diagnostic power of relative sit-to-stand muscle power, grip strength, and gait speed for identifying a history of recurrent falls and fractures in older adults

PURPOSE

To compare the diagnostic value of relative sit-to-stand muscle power with grip strength or gait speed for identifying a history of recurrent falls and fractures in older adults.

METHODS

Data from an outpatient clinic included anthropometry (height/weight), bone density, 5 times sit-to-stand time (stopwatch and standardized chair), grip strength (hydraulic dynamometer), and gait speed (4 m). Relative sit-to-stand muscle power (W.kg^-1, normalised to body mass) was calculated using a validated equation. Outcomes of falls (past 1 year) and fractures (past 5 years) were self-reported and verified by medical records wherever possible. Binary logistic regression considering for potential confounders (age, sex, BMI, Charlson comorbidity index, femoral neck bone density) and receiver operating characteristics (ROC) curves were used in statistical analysis.

RESULTS

508 community-dwelling older adults (median age: 78 years, interquartile range: 72, 83, 75.2% women) were included. Compared to greater relative sit-to-stand muscle power (1.62-3.78W.kg^-1 for women; 2.03-3.90W.kg^-1 for men), those with extremely low relative sit-to-stand muscle power were 2.35 (95% CI 1.54, 3.60, p < 0.001) and 2.41 (95% CI 1.25, 4.65, p = 0.009) times more likely to experience recurrent falls and fractures, respectively, in fully adjusted model. Compared to grip strength or gait speed, relative sit-to-stand muscle power showed the highest area under the ROC curve for identifying recurrent falls (AUC: 0.64) and fractures (AUC: 0.62). All tests showed low diagnostic power (AUC: < 0.7).

CONCLUSION

Relative sit-to-stand muscle power performed slightly (but not statistically) better than grip strength or gait speed for identifying a history of recurrent falls and fractures in older adults. However, all tests showed low diagnostic power.

Cost-Effectiveness of the ENJOY Seniors Exercise Park for Older People: A Pre-Post Intervention Study

BACKGROUND

The Exercise interveNtion outdoor proJect in the cOmmunitY (ENJOY) Seniors Exercise Park program uses specialized outdoor equipment and a physical activity program to engage older people in physical activity, with multiple health benefits. We determined the cost-effectiveness of the ENJOY program.

METHODS

The economic evaluation compared health care utilization costs 6 months prior to and 6 months post ENJOY program participation. Incremental cost-utility analysis for the primary aim (quality of life) and incremental cost-effectiveness analysis for the secondary aim (falls) were used. Analyses took a societal perspective inclusive of Australian government-funded health care and pharmaceuticals in addition to hospitalizations, community-based nursing and allied health, and community services. Productivity costs were also calculated.

RESULTS

Fifty participants (average age 72.8 y [SD 7.4] and 78.0% [n = 39/50] women) were included. Participation in the ENJOY program reduced health care costs in the 6 months following the program: preintervention, $9764.49 (SD $26,033.35); postintervention, $5179.30 (SD $3826.64); observed postintervention reduction -$4.585.20 (95% confidence interval, -$12,113.99 to $2943.59; P = .227) without compromising quality of life (mean difference [MD] 0.011; 95% confidence interval, -0.034 to 0.056; P = .631) or increasing the likelihood of a fall (-0.5; 95% confidence interval, 0.00 to -0.50; P = .160). The ENJOY intervention is likely cost-effective.

CONCLUSIONS

Planning for shared community spaces should consider the benefits of a Seniors Exercise Park as part of the built environment.

Handgrip strength is associated with learning and verbal fluency in older men without dementia: insights from the NHANES

Low handgrip strength, a hallmark measure of whole-body strength, has been linked with greater odds of cognitive decline and dementia; however, conflicting findings, which could be due to population characteristics and choice of tools, such for the assessment of handgrip strength and cognitive function domains, also exist. Therefore, we examined the relationship of handgrip strength with a comprehensive list of tests to assess domains of cognitive function using a representative sample of US older men and women without neurodegenerative disorders such as dementia. We analyzed cross-sectional data from the US National Health and Nutrition Examination Survey (NHANES) between 2011 and 2014, with a study cohort of 777 older adults (380 men and 397 women) above 60 years of age. Handgrip strength was assessed using a handgrip dynamometer, while cognitive function was assessed through the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Word List Learning Test (WLLT), Word List Recall Test (WLRT), Intrusion Word Count Test (WLLT-IC and WLRT-IC), the Animal Fluency Test (AFT), and the Digit Symbol Substitution Test (DSST). Sex-stratified multiple linear regression analyses were performed upon covariate adjustment for age, ethnicity, socio-economic status, education, medical history, body mass index, physical activity, energy, protein, and alcohol intake. Maximal handgrip strength was positively associated with cognitive function scores, including CERAD WLLT (P = 0.009, R² = 0.146) and AFT (P = 0.022, R² = 0.024) in older men, but not in women (CERAD WLLT: P = 0.253, AFT: P = 0.370). No significant associations with CERAD WLLRT (men: P = 0.057, women: P = 0.976), WLLT-IC (men: P = 0.671, women: P = 0.869), WLLRT-IC (men: P = 0.111, women: P = 0.861), and DSST (men: P = 0.108, women: P = 0.091) were observed. Dose-response curves exhibited a prominent linear relationship between all significant associations after covariate adjustment, with no indication of a plateau in these relationships. In conclusion, higher handgrip strength was independently associated with better learning ability for novel verbal information and verbal fluency in US men over the age of 60 and without dementia. Longitudinal studies are required to confirm whether muscle strength independently predicts cognitive function changes in older adults in a sex-specific manner, and whether this connection is affirmed to the possibility of reverse causation due to declines in physical activity levels in the preclinical phase of dementia.

Undercarboxylated osteocalcin and ibandronate combination ameliorates hindlimb immobilization-induced muscle wasting

Immobilization leads to muscle wasting and insulin resistance, particularly during aging. Undercarboxylated osteocalcin (ucOC) has been suggested to improve muscle mass and glucose metabolism. Bisphosphonates, an anti-osteoporosis treatment, might protect muscle wasting independent of ucOC. We hypothesize that the combination of ucOC and ibandronate (IBN) treatments has superior protective effects against immobilization-induced muscle wasting and insulin resistance than either treatment alone. C57BL/6J mice were hindlimb-immobilized for two weeks, with injections of vehicle, ucOC (90 ng/g daily) and/or IBN (2 μg/g weekly). Insulin/oral glucose tolerance tests (ITT/OGTT) were performed. Immediately after immobilization, muscles (extensor digitorum longus [EDL], soleus, tibialis anterior [TA], gastrocnemius, and quadriceps) were isolated and measured for muscle mass. Insulin-stimulated glucose uptake (EDL and soleus) was examined. Phosphorylation/expression of proteins in anabolic/catabolic pathways were examined in quadriceps. Primary human myotubes derived from older adult muscle biopsies were treated with ucOC and/or IBN, then signaling proteins were analyzed. Combined treatment, but not individual treatments, significantly increased muscle weight/body weight ratio in immobilized soleus (31.7 %; p = 0.013) and quadriceps (20.0 %; p = 0.0008) muscles, concomitant with elevated p-Akt (S473)/Akt ratio (p = 0.0047). Combined treatment also enhanced whole-body glucose tolerance (16.6 %; p = 0.0011). In human myotubes, combined treatment stimulated greater activation of ERK1/2 (p = 0.0067 and 0.0072) and mTOR (p = 0.036), and led to a lesser expression of Fbx32 (p = 0.049) and MuRF1 (p = 0.048), than individual treatments. These findings suggest a potential therapeutic role of ucOC and bisphosphonates combination in protecting against muscle wasting induced by immobilization and aging. KEY POINTS: Undercarboxylated osteocalcin (ucOC) has been suggested to improve muscle mass and glucose metabolism. Bisphosphonates, an anti-osteoporosis treatment, might protect muscle wasting independent of ucOC. The combination treatment of ucOC and ibandronate was shown to exert greater therapeutic effect against immobilization-induced muscle wasting, and lead to greater activation of anabolic pathway and less expression of catabolic signaling proteins in myotubes derived from older adults, compared to individual treatments. The combination treatment was found to improve whole-body glucose tolerance. Our findings suggest a potential therapeutic role of ucOC and bisphosphonates combination in protecting against muscle wasting induced by immobilization and aging. Abstract figure legend Undercarboxylated osteocalcin (ucOC) and ibandronate (IBN) combination improves muscle mass and glucose disposal. Two weeks of hindlimb immobilization in mice led to leg muscle atrophy as well as muscle insulin resistance. Injections of both undercarboxylated osteocalcin (intraperitoneal [IP]) and ibandronate (subcutaneous [SC]) alleviated muscle wasting in a muscle type-specific manner. In addition, this combination treatment improved glucose disposal in mice. In both immobilized mouse muscle and human primary myotubes derived from older adults, the combination treatment with ucOC and IBN resulted in greater activation of proteins involved in anabolic signaling pathway, including Akt and mTORC1. In primary myotubes, this treatment reduced expression of proteins involved in catabolic signaling pathway, such as Fbx32 and MuRF1. These findings suggest that ucOC and bisphosphonates combination has a potential in treating muscle wasting and insulin resistance induced by immobilization and aging. This article is protected by copyright. All rights reserved.

Very Low and High Levels of Vitamin D Are Associated with Shorter Leukocyte Telomere Length in 148,321 UK Biobank Participants

Background: Shorter leukocyte telomere length (LTL) is observed in multiple age-related diseases, which are also associated with vitamin D deficiency (i.e., osteosarcopenia, neurocognitive disorders, cancer, osteoarthritis, etc.), suggesting a close association between vitamin D and LTL. In this study, we examined the relationship between vitamin D levels and LTL in older participants of the UK Biobank. Methods: Data were collected from the UK Biobank. Participants aged 60 and older (n = 148,321) were included. Baseline LTL was measured using a multiplex qPCR technique and expressed as the ratio of the telomere amplification product (T) to that of a single-copy gene (S) (T/S ratio). Serum 25-hydroxyvitamin D (25OHD) was stratified by z score and linked to LTL in a linear regression model adjusting for covariates. Results: Compared to the medium level, a low (in the range of 16.6 nmol/L, 29.7 nmol/L) or extremely low (≤16.6 nmol/L) level of serum 25OHD was associated with shorter LTL: 0.018 SD (standardized β = −0.018, 95% CI −0.033 to −0.003, p = 0.022) and 0.048 SD (standardized β = −0.048, 95% CI −0.083 to −0.014, p = 0.006), respectively. Additionally, the high serum 25OHD groups (>95.9 nmol/L) had 0.038 SD (standardized β = −0.038, 95% CI −0.072 to −0.004, p = 0.030) shorter mean LTL than the group with medium 25OHD levels. The associations above were adjusted for multiple variables. Conclusions: In this population-based study, we identified an inverted U-shape relationship between LTL and vitamin D status. Our findings could be affected by unmeasured confounders. Whether high or low vitamin D-associated shorter LTL is mechanistically related to age-related conditions remains to be elucidated.

Comparing the Fracture Profile of Osteosarcopenic Older Adults with Osteopenia/Osteoporosis Alone

PURPOSE

To determine whether osteosarcopenia is associated with a greater likelihood of recurrent fractures, as well as type of fracture, than osteopenia/osteoporosis or sarcopenia alone.

METHODS

Anthropometry (height/weight; scales and stadiometer), body composition (bone mineral density [BMD] and appendicular lean mass; dual-energy x-ray absorptiometry), grip strength (hydraulic dynamometer), and gait speed (4 m) were measured in an outpatient clinic. WHO definition for osteopenia/osteoporosis (BMD T-score below -1 SDs) while sarcopenia was defined by SDOC or EWGSOP2. Number and location of fractures within the past 5 years were self-reported and verified by medical records (unverified fractures excluded). Univariable and multivariable regressions were used to examine the association between the exposure and outcome while adjusting for confounders.

RESULTS

481 community-dwelling older adults (median age: 78, IQR: 72, 83; 75.9% women) were included. Prevalence of osteosarcopenia depended on the definition (SDOC: 179 (37.2%); EWGSOP2: 123 (25.6%)). In multivariable analysis adjusting for age, sex, alcohol, smoking, BMI, lowest BMD T-score, physical activity, and comorbidities, the likelihood of recurrent fractures (≥ 2 vs 0-1) was significantly higher in those with osteosarcopenia versus osteopenia/osteoporosis irrespective of the definition (SDOC: odds ratio [OR]: 1.63, 95% CI: 1.03, 2.59, p = 0.037; EWGSOP2: OR: 1.83, 95% CI: 1.12, 3.01, p = 0.016]. Associations with sarcopenia alone (SDOC: 10; EWGSOP2: 7) were not possible due to the extremely low prevalence of this condition in those with normal BMD.

CONCLUSION

Our data suggest osteosarcopenia is associated with a greater likelihood of recurrent fractures versus osteopenia/osteoporosis alone. Further studies are needed to evaluate the relationship with sarcopenia alone.

Using minimal clinically important differences to measure long-term transitions of osteosarcopenia: The New Mexico Aging Process Study

BACKGROUND/OBJECTIVE

By having a better understanding of transitions in osteosarcopenia, interventions to reduce morbidity and mortality can be better targeted. The aim of this study was to show the rationale and method of using minimal clinically important differences (MCID's) to classify transitions, and the effects of demographic variables on transitions in a 9-year follow-up data from the New Mexico Aging Process Study (NMAPS).

METHODS

Transitions were identified in four aspects of osteosarcopenia: bone mineral density (BMD), appendicular skeletal muscle mass/body mass index ratio (ASM/BMI), grip strength and gait speed. Transitions were identified using a MCID score. As there is currently no available MCID for BMD and ASM/BMI, those were determined using a distribution-based and an anchor-based method. Total transitions were calculated for all four measures of osteosarcopenia in all transition categories (maintaining a health status, beneficial transition, harmful transitions). Poisson regression was used to test for effects of demographic variables, including age, sex, physical activity, medication, and health status, on transitions.

RESULTS

Over the 9-year follow-up, a total of 2163 MCID-derived BMD transitions were reported, 1689 ASM/BMI transitions, 2339 grip strength transitions, and 2151 gait speed transitions. Additionally, some MCID-derived transition categories were associated with sex, age, and health status.

CONCLUSION

Use of MCID-derived transitions reflected the fluctuation and the dynamic nature of health in older adults. Future research should focus on transitions of modifiable markers in osteosarcopenia to design intervention trials.

The Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR) sarcopenia diagnosis and management task force: Findings from the consumer expert Delphi process

OBJECTIVES

To develop guidelines, informed by health-care consumer values and preferences, for sarcopenia prevention, assessment and management for use by clinicians and researchers in Australia and New Zealand.

METHODS

A three-phase Consumer Expert Delphi process was undertaken between July 2020 and August 2021. Consumer experts included adults with lived experience of sarcopenia or health-care utilisation. Phase 1 involved a structured meeting of the Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR) Sarcopenia Diagnosis and Management Task Force and consumer representatives from which the Phase 2 survey was developed. In Phase 2, consumers from Australia and New Zealand were surveyed online with opinions sought on sarcopenia outcome priorities, consultation preferences and interventions. Findings were confirmed and disseminated in Phase 3. Descriptive statistical analyses were performed.

RESULTS

Twenty-four consumers (mean ± standard deviation age 67.5 ± 12.8 years, 18 women) participated in Phase 2. Ten (42%) identified as being interested in sarcopenia, 7 (29%) were health-care consumers and 6 (25%) self-reported having/believing they have sarcopenia. Consumers identified physical performance, living circumstances, morale, quality of life and social connectedness as the most important outcomes related to sarcopenia. Consumers either had no preference (46%) or preferred their doctor (40%) to diagnose sarcopenia and preferred to undergo assessments at least yearly (54%). For prevention and treatment, 46% of consumers preferred resistance exercise, 2-3 times per week (54%).

CONCLUSIONS

Consumer preferences reported in this study can inform the implementation of sarcopenia guidelines into clinical practice at local, state and national levels across Australia and New Zealand.

Orthostatic hypotension and neurocognitive disorders in older women: Results from the EPIDOS cohort study

BACKGROUND

Although it is well-admitted that cardiovascular health affects cognition, the association between orthostatic hypotension (OH) and cognition remains unclear. The objectives of the present study were i) to determine among the EPIDOS cohort (EPIdémiologie de l'OStéoporose) whether OH was cross-sectionally associated with cognitive impairment at baseline, and ii) whether baseline OH could predict incident cognitive decline after 7 years of follow-up.

METHODS

Systolic and Diastolic Blood Pressure (SBP and DBP) changes while standing (ie, ΔSBP and ΔDBP, in %) were measured at baseline among 2,715 community-dwelling older women aged 75 years and older using no antihypertensive drugs from the French EPIDOS cohort. OH was defined as a decrease in SBP ≥20 mmHg and/or a decrease in DBP ≥10 mmHg within 3 min after standing. Cognitive impairment was defined as a Short Portable Mental Status Questionnaire (SPMSQ) score <8 (/10). Among those without cognitive impairment at baseline, a possible incident onset of cognitive decline was then sought after 7 years of follow-up among 257 participants.

RESULTS

Baseline ΔSBP was associated with baseline cognitive impairment (adjusted OR = 1.01, p = 0.047), but not with incident onset of cognitive decline after 7 years (adjusted OR = 0.98, p = 0.371). Neither baseline OH nor baseline ΔDBP were associated with cognitive impairment neither at baseline (p = 0.426 and p = 0.325 respectively) nor after 7 years (p = 0.180 and p = 0.345 respectively).

CONCLUSIONS

SBP drop while standing, but neither OH per se nor DBP drop while standing, was associated with baseline cognitive impairment in older women. The relationship between OH and cognitive impairment appears more complex than previously expected.

Sarcopenic obesity definitions and their associations with physical frailty in older Brazilian adults: data from the SARCOS study

Objective

To identify the obesity diagnosis with the highest association with physical frailty associated with sarcopenia EWGSOP II (sarcopenic obesity).

Subjects and methods

We performed a cross-sectional analysis of 371 community-dwelling older adults. Appendicular skeletal lean mass and total body fat (TBF) were assessed using dual-energy x-ray absorptiometry, and physical frailty was defined using Fried's criteria. The phenotypes were identified according to the presence of sarcopenia by EWGSOP II and obesity, which was diagnosed using two concepts: BMI obesity (BMI ≥ 30 kg/m²) and TBF obesity (percentage of TBF ≥ 35% for women and ≥ 25% for men). Finally, the association of each group with physical frailty was evaluated.

Results

The mean age was 78.15 ± 7.22 years. Sarcopenia EWGSOP II was diagnosed in 19.8% (n = 73), body mass index obesity was identified in 21.8% (n = 81), TBF obesity was identified in 67.7% (n = 251), and physical frailty was identified in 38.5% (n = 142). In a regression analysis for frailty, sarcopenic TBF obesity presented an odds ratio of 6.88 (95% confidence interval 2.60-18.24; p < 0.001).

Conclusion

In older Brazilian adults, sarcopenic obesity diagnosed by TBF obesity has a robust association with frailty and is independent of body mass index.

Consensus guidelines for sarcopenia prevention, diagnosis and management in Australia and New Zealand

BACKGROUND

Sarcopenia is an age-associated skeletal muscle condition characterized by low muscle mass, strength, and physical performance. There is no international consensus on a sarcopenia definition and no contemporaneous clinical and research guidelines specific to Australia and New Zealand. The Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR) Sarcopenia Diagnosis and Management Task Force aimed to develop consensus guidelines for sarcopenia prevention, assessment, management and research, informed by evidence, consumer opinion, and expert consensus, for use by health professionals and researchers in Australia and New Zealand.

METHODS

A four-phase modified Delphi process involving topic experts and informed by consumers, was undertaken between July 2020 and August 2021. Phase 1 involved a structured meeting of 29 Task Force members and a systematic literature search from which the Phase 2 online survey was developed (Qualtrics). Topic experts responded to 18 statements, using 11-point Likert scales with agreement threshold set a priori at >80%, and five multiple-choice questions. Statements with moderate agreement (70%-80%) were revised and re-introduced in Phase 3, and statements with low agreement (<70%) were rejected. In Phase 3, topic experts responded to six revised statements and three additional questions, incorporating results from a parallel Consumer Expert Delphi study. Phase 4 involved finalization of consensus statements.

RESULTS

Topic experts from Australia (n = 62, 92.5%) and New Zealand (n = 5, 7.5%) with a mean ± SD age of 45.7 ± 11.8 years participated in Phase 2; 38 (56.7%) were women, 38 (56.7%) were health professionals and 27 (40.3%) were researchers/academics. In Phase 2, 15 of 18 (83.3%) statements on sarcopenia prevention, screening, assessment, management and future research were accepted with strong agreement. The strongest agreement related to encouraging a healthy lifestyle (100%) and offering tailored resistance training to people with sarcopenia (92.5%). Forty-seven experts participated in Phase 3; 5/6 (83.3%) revised statements on prevention, assessment and management were accepted with strong agreement. A majority of experts (87.9%) preferred the revised European Working Group for Sarcopenia in Older Persons (EWGSOP2) definition. Seventeen statements with strong agreement (>80%) were confirmed by the Task Force in Phase 4.

CONCLUSIONS

The ANZSSFR Task Force present 17 sarcopenia management and research recommendations for use by health professionals and researchers which includes the recommendation to adopt the EWGSOP2 sarcopenia definition in Australia and New Zealand. This rigorous Delphi process that combined evidence, consumer expert opinion and topic expert consensus can inform similar initiatives in countries/regions lacking consensus on sarcopenia.

Osteoporosis and Bone Marrow Adipose Tissue

PURPOSE OF REVIEW

This review focuses on the recent findings regarding bone marrow adipose tissue (BMAT) concerning bone health. We summarize the variations in BMAT in relation to age, sex, and skeletal sites, and provide an update on noninvasive imaging techniques to quantify human BMAT. Next, we discuss the role of BMAT in patients with osteoporosis and interventions that affect BMAT.

RECENT FINDINGS

There are wide individual variations with region-specific fluctuation and age- and gender-specific differences in BMAT content and composition. The Bone Marrow Adiposity Society (BMAS) recommendations aim to standardize imaging protocols to increase comparability across studies and sites. Water-fat imaging (WFI) seems an accurate and efficient alternative for spectroscopy (¹H-MRS). Most studies indicate that greater BMAT is associated with lower bone mineral density (BMD) and a higher prevalence of vertebral fractures. The proton density fat fraction (PDFF) and changes in lipid composition have been associated with an increased risk of fractures independently of BMD. Therefore, PDFF and lipid composition could potentially be future imaging biomarkers for assessing fracture risk. Evidence of the inhibitory effect of osteoporosis treatments on BMAT is still limited to a few randomized controlled trials. Moreover, results from the FRAME biopsy sub-study highlight contradictory findings on the effect of the sclerostin antibody romosozumab on BMAT. Further understanding of the role(s) of BMAT will provide insight into the pathogenesis of osteoporosis and may lead to targeted preventive and therapeutic strategies.

Bone-muscle crosstalk following exercise plus Ursolic acid by myomiR-133a/Cx43-Runx2 axis in aged type 2 diabetes rat models

Natural bioactive compound, Ursolic acid (UA), plus different types of exercise may exert the action on glycemic control, leading to clinical benefits in the prevention and treatment of aging/diabetes-associated complications. So, this study examined the effects of eight weeks combination of 250 mg of UA per day per kilogram of body weight of rat as well as resistance/endurance training on miR-133a expression across serum, bone marrow, skeletal muscle, and Connexin 43 (Cx43)-Runt-related transcription factor 2 (Runx2) signaling axis in high-fat diet and low-dose streptozotocin-induced T2D (here, HFD/STZ-induced T2D). The study was conducted on 56 male Wistar rats (427 ± 44 g, 21 months old), having HFD/STZ-induced T2D randomly assigned into 7 groups of 8 including (1) sedentary non-diabetic old rats (C); (2) sedentary type 2 diabetes animal model (D); (3) sedentary type 2 diabetes animal model + UA (DU); (4) endurance-trained type 2 diabetes animal model (DE); (5) resistance-trained type 2 diabetes animal model (DR); (6) endurance-trained type 2 diabetes animal model + UA (DEU); and (7) resistance-trained type 2 diabetes animal model + UA (DRU). Resistance training included a model of eight weeks of ladder resistance training at 60-80% maximal voluntary carrying capacity (MVCC) for five days/week. Treadmill endurance exercise protocol included eight weeks of repetitive bouts of low-/high-intensity training with 30%-40% and 60%-75% maximal running speed for five days/week, respectively. UA Supplementary groups were treated with 500 mg of UA per kg of high-fat diet per day. The results revealed significant supplement and exercise interaction effects for the BM miR-133a (p = 0.001), the bone marrow Runx2 (p = 0.002), but not the serum miR-133a (p = 0.517), the skeletal muscle miR-133a (p = 0.097) and the Cx43 (p = 0.632). In conclusion, only eight weeks of resistance-type exercise could affect miR-133a profile in muscles and osteoblast differentiation biomarker RUNX2 in aged T2D model of rats. 250 mg of UA per kilogram of body weight rat per day was administered orally, less than the sufficient dose for biological and physiological impacts on osteoblast differentiation biomarkers in aged T2D model of rats following eight weeks.

Relationship Between Plasma Homocysteine and Bone Density, Lean Mass, Muscle Strength and Physical Function in 1480 Middle-Aged and Older Adults: Data from NHANES

Hyperhomocysteinemia induces oxidative stress and chronic inflammation (both of which are catabolic to bone and muscle); thus, we examined the association between homocysteine and body composition and physical function in middle-aged and older adults. Data from the National Health and Nutrition Examination Survey was used to build regression models. Plasma homocysteine (fluorescence immunoassay) was used as the exposure and bone mineral density (BMD; dual-energy X-ray absorptiometry; DXA), lean mass (DXA), knee extensor strength (isokinetic dynamometer; newtons) and gait speed (m/s) were used as outcomes. Regression models were adjusted for confounders (age, sex, race/Hispanic origin, height, fat mass %, physical activity, smoking status, alcohol intakes, cardiovascular disease, diabetes, cancer and vitamin B12). All models accounted for complex survey design by using sampling weights provided by NHANES. 1480 adults (median age: 64 years [IQR: 56, 73]; 50.3% men) were included. In multivariable models, homocysteine was inversely associated with knee extensor strength (β = 0.98, 95% CI 0.96, 0.99, p = 0.012) and gait speed (β = 0.85, 95% CI 0.78, 0.94, p = 0.003) and borderline inversely associated with femur BMD (β = 0.84, 95% CI 0.69, 1.03, p = 0.086). In the sub-group analysis of older adults (≥ 65 years), homocysteine was inversely associated with gait speed and femur BMD (p < 0.05) and the slope for knee extensor strength and whole-body BMD were in the same direction. No significant associations were observed between homocysteine and total or appendicular lean mass in the full or sub-group analysis. We found inverse associations between plasma homocysteine and muscle strength/physical function, and borderline significant inverse associations for femur BMD.

GDF-15 Is Associated with Poor Physical Function in Prefrail Older Adults with Diabetes

Introduction

Growth differentiation factor 15 (GDF-15) has been shown to be a metabolic and appetite regulator in diabetes mellitus (DM) and obesity. We aimed to investigate (i) the association between GDF-15 and DM with and without poor physical function independent of inflammation and (ii) the prediction model for poor physical function in prefrail older adults.

Methods

A cross-sectional study of 108-prefrail participants ≥60 years recruited for multidomain interventions. Data was collected for demographics, cognition, function, frailty, nutrition, handgrip strength (HGS), short physical performance battery (SPPB), and gait speed. Serum concentrations of GDF-15, IL-6, and TNF-α were measured. GDF-15 was classified into tertiles (T1, T2, and T3), and its association was studied with DM and physical function (DM poor physical function, DM no poor physical function, no DM poor physical function, and no DM no poor physical function).

Results

Compared with T1, participants in T3 were significantly older, had a lower education level, had almost three times higher prevalence of DM, slower gait speed, longer chair-stand time, and lower SPPB scores. On multivariate analysis, the odds of having both DM and poor physical performance compared to having no DM and no poor physical performance were significantly higher in GDF-15 T3 vs. GDF-15 T1 (aOR 9.7, 95% CI 1.4-67.7; p = 0.021), and the odds of having DM no poor physical function compared to having no DM and no poor physical performance were significantly higher in GDF-15 T2 (aOR 12.7, 95% CI 1.1-143.7; p = 0.040) independent of BMI, IL-6, TNF-α, nutrition, physical function, education, age, and gender.

Conclusion

The association of GDF-15 with DM-associated poor physical function is independent of inflammation in prefrail older adults. Its causal-association link needs to be determined in longitudinal studies.

Defining terms commonly used in sarcopenia research: a glossary proposed by the Global Leadership in Sarcopenia (GLIS) Steering Committee

METHODS

The aim of this paper is to define terms commonly related to sarcopenia to enable standardization of these terms in research and clinical settings. The Global Leadership Initiative in Sarcopenia (GLIS) aims to bring together leading investigators in sarcopenia research to develop a single definition that can be utilized worldwide; work on a global definition of sarcopenia is ongoing. The first step of GLIS is to develop the common terminology, or a glossary, that will facilitate agreement on a global definition of sarcopenia as well as interpretation of clinical and research findings.

RESULTS

Several terms that are commonly used in sarcopenia research are defined, including self-reported measures of function and ability; objective physical performance tests; and measures related to muscle function and size.

CONCLUSION

As new methods and technologies are developed, these definitions may be expanded or refined over time. Our goal is to promote this common language to describe sarcopenia and its components in clinical and research settings in order to increase clinical awareness and research interest in this important condition. We hope that the use of common terminology in sarcopenia research will increase understanding of the concept and improve communication around this important age-related condition.

Higher bone remodeling biomarkers are related to a higher muscle function in older adults: Effects of acute exercise

Bone and muscle are closely linked mechanically and biochemically. Bone hormones secreted during bone remodeling might be linked to muscle mass and strength maintenance. Exercise elicits high mechanical strain and is essential for bone health. However, the relationship between commonly used bone turnover markers (BTMs) and muscle function in community dwelling older adults remains unclear. It is also unknown how acute exercise with differing mechanical strain may affect BTMs, and whether baseline muscle function alters BTM responses differently. We tested the hypothesis that BTMs are associated with muscle function, and that acute exercise could change the circulating levels of BTMs. Thirty-five older adults (25 females/10 males, 72.8 ± 6.0 years) participated. Baseline assessments included body composition (DXA), handgrip strength and a physical performance test (PPT) (gait speed, timed-up-and-go [TUG], stair ascent/descent). Leg muscle quality (LMQ) and stair climb power (SCP) were calculated. Participants performed (randomized) 30 min aerobic (AE) (cycling 70%HR_Peak) and resistance (RE) (leg press 70%RM, jumping) exercise. Serum β-isomerized C-terminal telopeptides (β-CTX), procollagen of type I propeptide (P1NP), total osteocalcin (t)OC and ucOC were assessed at baseline and post-exercise. Data were analyzed using linear mixed models and simple regressions, adjusted for sex. At baseline, higher muscle strength (LMQ, handgrip) was related to higher P1NP, higher SCP was related to higher P1NP and β-CTX, and better physical performance (lower PPT) related to higher P1NP and β-CTX (p < 0.05). Exercise, regardless of mode, decreased β-CTX and tOC (all p < 0.05), while P1NP and ucOC remained unaltered. Higher baseline handgrip strength, SCP and LMQ was associated with lower post-exercise β-CTX responses, and poorer baseline mobility (increased TUG time) was associated with higher post-exercise β-CTX. Independently of exercise mode, acute exercise decreased β-CTX and tOC. Our data suggest that in older adults at baseline, increased BTM levels were linked to better muscle function. Altogether, our data strengthens the evidence for bone-muscle interaction, however, mechanisms behind this specific component of bone-muscle crostalk remain unclear.