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.

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.

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).

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.

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.

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.

Effects of 3 months of multi-nutrient supplementation on the immune system and muscle and respiratory function of older adults in aged care (The Pomerium Study): protocol for a randomised controlled trial.

INTRODUCTION: Immunosenescence leads to increased morbidity and mortality associated with viral infections and weaker vaccine responses. This has been well documented for seasonal influenza and the current pandemic with SARS-CoV-2 (COVID-19), which disproportionately impact older adults, particularly those in residential aged care facilities. Inadequate nutrient intakes associated with impaired immunity, respiratory and muscle function are likely to augment the effects of immunosenescence. In this study, we test whether the impact of inadequate nutrition can be reversed using multi-nutrient supplementation, consequently enhancing vaccine responses, reducing the risk of viral infections and improving respiratory and muscle function. METHODS AND ANALYSIS: The Pomerium Study is a 3-month, single-blind, randomised, controlled trial testing the effects of two daily servings of an oral multi-nutrient supplement (330 kcal, 20 g protein, 1.5 g calcium 3-hydroxy-3-methylbutyrate monohydrate (CaHMB), 449 mg calcium, 500 IU vitamin D3 and 25 vitamins and minerals) on the immune system and muscle and respiratory function of older adults in aged care in Melbourne, Australia. 160 older adults (≥75 years old) will be recruited from aged care facilities and randomised to treatment (multi-nutrient supplement) or control (usual care). The primary outcome is a change in T-cell subsets CD8 + and CD28null counts at months 1 and 3. Secondary outcomes measured at baseline and month 3 are multiple markers of immunosenescence (also at 1 month), body composition (bioimpedance), handgrip strength (dynamometer), physical function (short physical performance battery), respiratory function (spirometry) and quality of life (EQ-5D-5L). Incidence and complications of COVID-19 and/or viral infections (ie, hospitalisation, complications or death) will be recorded throughout the trial, including 3 months after supplementation is ceased. ETHICS AND DISSEMINATION: This study was approved by Melbourne Health Human Research Ethics Committee (Ref No. HREC/73985/MH-2021, ERM Ref No. RMH73985, Melbourne Health Site Ref No. 2021.115). Written informed consent will be obtained from participants. Results will be published in peer-reviewed journals and made available to key aged care stakeholders, including providers, residents, and government bodies. TRIAL REGISTRATION NUMBER: ACTRN12621000420842.

Factor analysis to determine relative contributions of strength, physical performance, body composition and muscle mass to disability and mobility disability outcomes in older men.

BACKGROUND: It is not known how measures of body composition, strength and physical performance are interrelated or how empirical groupings of these measures relate to disability and mobility disability. METHODS: Muscle mass was assessed by D3-creatine dilution (D3Cr muscle mass) in 1345 men (84.1 ± 4.1 years) enrolled in the Osteoporotic Fractures in Men (MrOS) study. Participants completed anthropomorphic measures, walk speed, grip strength, chair stands, and dual x-ray absorptiometry (DXA) estimated appendicular lean mass (ALM) and body fat percentage. Men reported limitations in mobility, activities of daily living (ADLs) and instrumental ADLs at initial and over 2.2 ± 0.3 years. Factor analysis reduced variables into related groups and negative binomial models calculated relative risk (RR) of factors with mobility and disability outcomes. RESULTS: Factor analysis reduced 10 variables into four factors: Factor 1, body composition, including ALM, body fat percentage, weight and muscle mass; Factor 2, body size and lean mass, including height, weight and ALM; Factor 3, muscle mass, strength and performance, including walk speed, chair stands, grip strength, and muscle mass; and Factor 4, lean mass and weight, including ALM and weight. Only Factor 3 was significantly associated (p-value < .001) with prevalent disability (RR per standard deviation increment in factor score (reflecting higher muscle mass, strength and physical performance) 0.44, 0.35-0.56) and mobility disability (RR 0.22, 0.17 0.28), and incident mobility disability (RR 0.37, 0.27-0.50). CONCLUSION: D3Cr muscle mass was the only body composition variable that co-segregated with strength and physical performance measures, and contributed to a factor that was associated with disability outcomes in older men.

Body composition reference ranges in community-dwelling adults using dual-energy X-ray absorptiometry: the Australian Body Composition (ABC) Study.

BACKGROUND: Reference ranges for lean mass (LM) and fat mass (FM) are essential in identifying soft tissue disorders; however, no such reference ranges exist for the most commonly used Hologic dual-energy X-ray absorptiometry (DXA) machine in Australia. METHODS: Cross-sectional study of community-dwelling adults (aged 18-88 years) who underwent a Hologic DXA scan at one of three commercialized densitometry centres in Australia. Age-specific and sex-specific percentile curves were generated for LM [LM, appendicular lean mass (ALM), ALM adjusted for height squared (ALM/h2 ), and ALM adjusted for body mass index (ALM/BMI)] and FM [FM, FM adjusted for height squared (FM/h2 ), appendicular fat mass, and android and gynoid fat] parameters using the LMS statistical method. Cutpoints equivalent to T-scores of -1, -2, and -2.5 standard deviations below the young mean reference group (20-29 years) were also generated for LM parameters. RESULTS: A total of 15 479 community-dwelling adults (54% men) with a median age of 33 years (interquartile range: 28, 42) were included. LM, ALM, and ALM/h2 remained stable until age 50, after which these parameters started to decline in both sexes. Compared with age 50, median percentiles of LM, ALM, and ALM/h2 declined by -5.9 kg, -3.7 kg, and -0.86 kg/m2 in men and by -2.5 kg, -1.8 kg, and -0.10 kg/m2 in women at age 70, respectively. Adjusting ALM for BMI (rather than height squared) resulted in different trends, with ALM/BMI decreasing from as early as age 20. Compared with age 20, median percentiles of ALM/BMI at age 40 declined by -0.10 kg/kg/m2 in men and by -0.06 kg/kg/m2 in women; and at age 70, ALM/BMI declined by -0.25 kg/kg/m2 in men and by -0.20 kg/kg/m2 in women. Cutpoints equivalent to T-scores of -1, -2, and -2.5 standard deviations for ALM/BMI were 1.01, 0.86, and 0.77 kg/kg/m2 in men and 0.70, 0.59, and 0.53 kg/kg/m2 in women, respectively. All FM parameters progressively increased from age 20 and continued up until age 70. CONCLUSIONS: We developed reference ranges for LM and FM parameters from Hologic DXA machines in a large cohort of Australian adults, which will assist researchers and clinicians in identifying soft tissue disorders such as obesity, sarcopenia, and cachexia.

Sarcopenia Definitions and Outcomes Consortium (SDOC) Criteria are Strongly Associated With Malnutrition, Depression, Falls, and Fractures in High-Risk Older Persons.

OBJECTIVES: Sarcopenia Definitions and Outcomes Consortium (SDOC) provides cut-points based on muscle weakness (low grip strength) and slowness (poor gait speed) for low-risk populations; however, it is unknown if these criteria apply to high-risk populations. We examined the association between SDOC criteria and important health status indicators in high-risk older persons. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: 356 community-dwelling older persons (median age: 79 years, interquartile range: 73, 83; 75.2% women) attending a falls and fractures clinic in Melbourne, Australia. METHODS: Grip strength (hydraulic dynamometer) and gait speed (over 4 m) were used to define sarcopenia using SDOC cut-points. Health measures included falls (past 1 year) and fractures (past 5 years) by self-report, and malnutrition, depression, balance confidence, fear of falling, static balance (limits of stability), dynamic balance (Four-Square Step Test), and body composition [body mass index and lean mass, fat mass, and bone density (via dual-energy x-ray absorptiometry)] were assessed using validated procedures. Fasting vitamin D and parathyroid hormone concentrations were measured by immunoassays. Participants were categorized as nonsarcopenic or sarcopenic based on the SDOC cut-points, and multivariate models were used to examine the association between sarcopenia and health status indicators while adjusting for confounding factors. RESULTS: After adjusting for covariates, sarcopenic older persons (n = 162, 45.5%) were positively associated with malnutrition [odds ratio (OR) 3.21, 95% confidence interval (CI) 1.63, 6.32], depression (OR 4.11, 95% CI 2.31, 7.29), fear of falling (OR 1.08, 95% CI 1.06, 1.10) as well as recurrent (2 or more) falls (OR 1.62, 95% CI 1.01, 2.59) and fractures (OR 2.26, 95% CI 1.17, 4.36), and negatively associated with poor balance confidence (OR 0.96, 95% CI 0.95, 0.97) (P < .05 vs nonsarcopenic). CONCLUSIONS AND IMPLICATIONS: SDOC criteria are strongly associated with important health status indicators in high-risk older persons, which strengthens the clinical utility of the SDOC in these populations.

A clinical guide to the pathophysiology, diagnosis and treatment of osteosarcopenia.

Advances in medicine have paved the way for older persons to live longer, but with more years spent living with disability and dependency. Many older persons are living with comorbidities such as osteoporosis (loss of bone mass) and sarcopenia (loss of muscle mass and function), two diseases that, when concurrent, form osteosarcopenia, a newly identified musculoskeletal syndrome. Osteosarcopenia impedes mobility and diminishes independence and thus quality of life. Evidence suggests the pathology of this syndrome comprises genetic polymorphisms, alterations in mechanotransduction, and localized or systemic crosstalk between growth factors and other proteins (myokines, osteokines, adipokines). As a direct result of an aging society, health outcomes such as falls and fractures will rise as the prevalence of osteosarcopenia increases. Two major risk factors for osteosarcopenia (other than age itself) are physical inactivity and poor nutrition. Addressing these modifiable risk factors can prevent, or at least delay, the onset of osteosarcopenia. Pharmaceutical treatments for osteosarcopenia are currently unavailable, although research trials are underway. This review provides an update from basic and clinical sciences on the biology, epidemiology (prevalence, risk factors and diagnosis) and treatments for osteosarcopenia, and recommends future research priorities to improve health outcomes for those living with or at risk of osteosarcopenia.

The diagnostic value of the Short Physical Performance Battery for sarcopenia.

BACKGROUND: Sarcopenia is defined as the age-related loss of muscle mass, strength, and physical performance. The original European Working Group on Sarcopenia in Older Persons (EWGSOP1) definition, and its revision (EWGSOP2), provide new cut-points and alternate measures for sarcopenia diagnosis. However, sarcopenia is rarely diagnosed in clinical settings owing to its labor-intensive diagnostic process. Given the Short Physical Performance Battery (SPPB) is a quick, easily administrable, and objective measure of muscle strength and physical performance, both of which are key components of sarcopenia, this study examined the diagnostic value of the SPPB for this muscle disease. METHODS: A cross-sectional analysis of 294 community-dwelling older persons (≥65 years) was conducted. Appendicular lean body mass [(ALM) divided by height squared (ALM/h2)], muscle strength (handgrip/sit to stand), and physical performance [gait speed, timed up and go (TUG) and SPPB] were assessed using validated procedures, while participants were diagnosed with sarcopenia following the EWGSOP1 and EWGSOP2 criteria. Diagnostic ability of the SPPB independently and combined with ALM/h2 for sarcopenia was determined using area under the curve (AUC). Potential cut-points were identified, and sensitivity and specificity calculated. RESULTS: Prevalence of sarcopenia ranged from 4 to 16% depending on the definition. The SPPB demonstrated moderate (AUC = 0.644-0.770) value in diagnosing sarcopenia, and a cut-point of ≤8points in SPPB performance resulted in high sensitivity (82-100%) but low specificity (36-41%) for diagnosing those with severe sarcopenia. CONCLUSIONS: The SPPB displayed acceptable value in diagnosing older adults with severe sarcopenia. Moreover, the high sensitivity of the SPPB when using the cut-point of ≤8 suggests it may be a favorable screening tool for sarcopenia in clinical settings where ALM measurements are not available.

Walking Speed and Muscle Mass Estimated by the D3-Creatine Dilution Method Are Important Components of Sarcopenia Associated With Incident Mobility Disability in Older Men: A Classification and Regression Tree Analysis.

OBJECTIVES: It is unknown whether muscle mass measured by the D3-creatine dilution method is a superior predictor of incident mobility disability than traditional components of sarcopenia definitions (including grip strength, walking speed, appendicular lean mass). The objective of this study was to determine the relative importance of strength; physical performance; and lean, fat, and muscle mass in predicting incident mobility disability in older men. DESIGN: Longitudinal cohort study of participants in the Osteoporotic Fractures in Men (MrOS) study. SETTING AND PARTICIPANTS: Muscle mass was assessed by D3-creatine dilution in 1098 men (aged 83.7 ± 3.7 years). Participants also completed anthropomorphic measures, 6-m walking speed (m/s), grip strength (kg), chair stands (seconds), and dual x-ray absorptiometry appendicular lean mass (ALM), and total body fat percentage. Men self-reported incident mobility disability defined by the development of an inability to complete at least one of walking 2-3 blocks, climbing 10 steps, or carrying 10 lb over 2.2 ± 0.3 years. METHODS: Classification and regression tree analysis was conducted to determine relative variable importance and algorithm cutpoints for predicting incident mobility disability. Given the proximity of walking speed with the primary outcome (mobility disability), analyses were conducted with and without walking speed. RESULTS: Walking speed followed by D3Cr muscle mass/weight were the most important variables (variable importance: 53% and 12%, respectively) in the prediction of self-reported incident mobility disability. D3Cr muscle mass was the most important variable in predicting incident mobility disability when walking speed was excluded, followed by chair stands (variable importance: 35% and 33%, respectively). Body fat percentage, ALM, and grip strength were not selected as nodes in either analysis and had low or negligible variable importance. CONCLUSIONS AND IMPLICATIONS: This study has provided valuable insights into the importance of different variables in predicting incident mobility disability in older men. Muscle mass by D3Cr may be a key tool for predicting the risk of negative outcomes in older adults in the future, particularly in post-acute and long-term care settings.

Osteosarcopenia: the Path Beyond Controversy.

PURPOSE OF REVIEW: Osteosarcopenia is commonly accepted as the presence of low muscle mass and function (sarcopenia) and low bone mineral density (osteopenia and osteoporosis). Osteosarcopenia remains a topic of controversy as researchers worldwide seek to elucidate whether osteosarcopenia is associated with greater risk of negative outcomes than its component parts. This review examines the latest research and controversies, and charts a path forward. RECENT FINDINGS: Osteosarcopenia may occur in 5-37% of community-dwelling adults over the age of 65. This wide range is driven by variation in population, setting, and definitions applied. These differences in study design have resulted in mixed findings in associations with adverse outcomes for older adults living with osteosarcopenia. Research into interventions to prevent or treat osteosarcopenia, such as exercise, protein supplementation, and pharmacotherapy, is in its infancy but examined herein. The absence of a consensus operational definition of sarcopenia, and inaccurate measures of muscle mass, has hampered global progress in the field. We present a case for the path forward by reflecting on our recent history.

Osteosarcopenia: epidemiology, diagnosis, and treatment-facts and numbers.

BACKGROUND: Osteosarcopenia, the presence of osteopenia/osteoporosis and sarcopenia, is an emerging geriatric giant, which poses a serious global health burden. METHODS AND RESULTS: The prevalence of osteosarcopenia ranges in community-dwelling older adults [5-37% (≥65 years)] with the highest rates observed in those with fractures (low-trauma fracture: ~46%; hip fracture: 17.1-96.3%). Among 2353 community-dwelling adults, risk factors associated with osteosarcopenia include older age [men: 14.3% (60-64 years) to 59.4% (≥75 years); women: 20.3% (60-64 years) to 48.3% (≥75 years), P < 0.05], physical inactivity [inverse relationship: 0.64, 95% confidence interval (CI) 0.46-0.88 (sexes combined)], low body mass index (inverse relationship: men: 0.84, 95% CI 0.81-0.88; women: 0.77, 95% CI 0.74-0.80), and higher fat mass (men: 1.46, 95% CI 1.11-1.92; women: 2.25, 95% CI 1.71-2.95). Among 148 geriatric inpatients, osteosarcopenic individuals demonstrate poorer nutritional status (mini-nutritional assessment scores: 8.50 ± 2.52 points, P < 0.001) vs. osteoporosis or sarcopenia alone, while among 253 older Australians, osteosarcopenia is associated with impaired balance and functional capacity [odds ratios (ORs): 2.56-7.19; P < 0.05] vs. non-osteosarcopenia. Osteosarcopenia also associates with falls (ORs: 2.83-3.63; P < 0.05), fractures (ORs: 3.86-4.38; P < 0.05), and earlier death [hazard ratio (1-year follow-up): 1.84, 95% CI; 0.69-4.92, P = 0.023] vs. non-osteosarcopenia. CONCLUSIONS: This syndrome is expected to grow in age-related and disease-related states, a likely consequence of immunosenescence coinciding with increased sedentarism, obesity, and fat infiltration of muscle and bone. Evidence suggests the pathophysiology of osteosarcopenia includes genetic polymorphisms, reduced mechanical loading, and impaired endocrine functioning, as well as altered crosstalk between muscle, bone, and fat cells. Clinicians should screen for osteosarcopenia via imaging methods (i.e. dual-energy X-ray absorptiometry) to quantify muscle and bone mass, in addition to assessing muscle strength (i.e. grip strength) and functional capacity (i.e. gait speed). A comprehensive geriatric assessment, including medical history and risk factors, must also be undertaken. Treatment of this syndrome should include osteoporotic drugs [bone anabolics/antiresorptives (i.e. teriparatide, denosumab, bisphosphates)] where indicated, and progressive resistance and balance exercises (at least 2-3 times/week). To maximize musculoskeletal health, nutritional recommendations [protein (1.2-1.5 g/kg/day), vitamin D (800-1000 IU/day), calcium (1300 mg/day), and creatine (3-5 g/day)] must also be met. It is anticipated that diagnosis and treatment for osteosarcopenia will become part of routine healthcare in the future. However, further work is required to identify biomarkers, which, in turn, may increase diagnosis, risk stratification, and targeted treatments to improve health outcomes.

The Joint Occurrence of Osteoporosis and Sarcopenia (Osteosarcopenia): Definitions and Characteristics.

OBJECTIVES: We sought to examine the associations of osteosarcopenia with physical performance, balance, and falls and fractures in community-dwelling older adults. Additionally, we aimed to determine which clinical outcomes are associated with specific components of osteosarcopenia. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: 253 participants (77% women; aged 77.9 ± 0.42 years) who presented for a falls and fractures risk assessment in Melbourne, Australia. METHODS: Participants were mobile, community-dwelling older adults (≥65 years) free of cognitive impairment. Body composition (via dual-energy x-ray absorptiometry), physical performance [via Timed Up and Go (TUG) and Short Physical Performance Battery (SPPB)], and balance [via Four-Square Step test (FSS) and posturography] were examined. Falls in the past year and fractures in the past 5 years were self-reported. Osteosarcopenia was defined as (1) low bone mineral density (BMD) [T score <-1 standard deviation (SD)] combined with sarcopenia and (2) osteoporosis (BMD T score ≤-2.5 SD) combined with severe sarcopenia. For sarcopenia, we employed the criteria of the European Working Group on Sarcopenia in Older People (EWGSOP1), the revised criteria (EWGSOP2), and that of the Foundation for the National Institutes for Health (FNIH). Kruskal-Wallis and logistic regression tests were used for statistical analysis. RESULTS: Osteosarcopenia was associated with worse SPPB, TUG, FSS, limit of stability, and falls and fractures history. Additionally, osteosarcopenia (using the severe sarcopenia classification) conferred an increased rate of falls [odds ratios (ORs) from 2.83 to 3.63; P < .05 for all] and fractures (ORs from 3.86 to 4.38; P < .05 for all) when employing the EWGSOP2 and FNIH definitions, respectively. CONCLUSIONS AND IMPLICATIONS: Compared with the nonosteosarcopenic group, those with osteosarcopenia had greater impairment of physical performance and balance. The EWGSOP2 and FNIH criteria resulted in the strongest associations with physical performance and self-reported falls and fractures.

The effect of protein supplements on functional frailty in older persons: A systematic review and meta-analysis.

BACKGROUND: The effect of protein supplementation in attenuating loss of muscle mass, strength and function in community-dwelling older people has been promising, however, its benefits in pre-frail and frail older people remains unclear. OBJECTIVE: To determine the effect of protein supplementation on muscle mass, strength and function in frail older people by reviewing and conducting meta-analysis of relevant randomized controlled trials (RCTs). DESIGN: This review was registered at PROSPERO (CRD42017079276) and conducted according to Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Using a pre-determined e-search strategy, we searched PubMed, Medline, EMBASE, CINAHL, LILACS, Web of Science, Cochrane and Scopus databases. Inclusion criteria were RCTs that assessed the effect of protein supplementation on muscle mass, strength and function in frail individuals aged ≥65 years. The main outcomes were lean body mass (LBM), handgrip, leg extension, leg press strength, short physical performance battery (SPPB) score, and gait velocity. RESULTS: Of the eight studies included in this review, 503 subjects were enrolled and four different protein supplements were assessed. Despite the variation in methodology, studies were homogenous with I-squared <10.0%. The meta-analysis showed no significant effect of protein supplementation on LBM (mean difference 1.17 kg, 95% CI: -1.97-4.3), handgrip (mean difference 0.15, 95% CI: -0.95-1.24), leg extension (mean difference -3.68 kg, 95% CI: -12.72-5.36), leg press (mean standardized difference 0.26 kg, 95% CI: -0.30-0.82), SPPB (mean difference 0.61, 95% CI: -0.02-1.23), or gait velocity (mean difference -0.20 m/s, 95% CI: -0.95-0.55). CONCLUSION: Protein supplementation alone does not significantly improve muscle mass, strength or function in pre-frail or frail older people.