Treadmill induced belt-accelerations may not accurately evoke the muscle responses to obstacle trips in older people.

BACKGROUND: Treadmill belt-accelerations are a commonly utilised surrogate for tripping, but their physiological validity is unknown. This study examined if a treadmill belt-acceleration induces lower limb muscle activation responses similar to a trip on a walkway. METHODS: 38 older people (65+ years) experienced one treadmill belt-acceleration and one walkway obstacle trip in random order. Muscle responses were assessed bilaterally using surface electromyography on the rectus femoris (RF), tibialis anterior (TA), semitendinosus (ST) and gastrocnemius medial head (GM). Unperturbed muscle activity, post-perturbation onset latency, peak magnitude, time to peak and co-contraction index (CCI) were examined. RESULTS: Muscle activity in the right ST was greater during unperturbed walking on the treadmill compared to walkway (P=0.011). Compared to a treadmill belt-acceleration, a walkway trip elicited faster onset latencies in all muscles; greater peak magnitudes in the left RF, TA, GM and right GM; faster time to peaks in the left TA and right GM; and lower knee and ankle muscle CCI (P<0.05). CONCLUSIONS: Walkway trips and treadmill belt-accelerations elicit distinct muscle activation patterns. While walkway trips induced faster and larger muscle responses, treadmill belt-accelerations involved greater co-contraction. Therefore, treadmill belt-accelerations may not accurately simulate the muscle responses to trips.

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.

The effects of optic flow on postural stability: Influence of age and fall risk.

BACKGROUND: Optic flow provides dynamic information relating to body position and motion with respect to visual frames of reference. This study investigated the effects of optic flow stimuli presented in four directions on postural stability in young and older adults. METHODS: Twenty-five young (20-40 years) and 51 older (≥65 years) people participated in this study, with the older group classified into low fall risk (n = 27), and high fall risk (n = 24) sub-groups. While standing in a dark room, participants viewed static scattered white dots for 30 s, followed by 30 s periods of optic flow consisting of white dots "moving" in one of four flow directions, randomised: radial expansion and contraction, circular anti-clockwise and clockwise. Centre of pressure (CoP) position, postural sway in anteroposterior (AP) and mediolateral (ML) axes, and muscle activity of tibialis anterior (TA), gastrocnemius medialis (GM) and tensor fascia latae (TFL) were recorded. RESULTS: Across groups, the four optic flow stimuli induced increased AP sway and three of the four optic flow stimuli induced increased ML sway, with concomitant increases in muscle activity, indicating optic flow stimuli induced a generalised destabilising, rather than a direction-specific, effect. Only one optic flow condition (radial contraction) induced a change in average CoP position, and this may reflect the adoption of a protective stance position to avoid a backward fall. Optic flow destabilised postural control more in older people compared with younger people, and radial expansion stimuli destabilised ML postural control more in the older high fall risk group compared with the older low fall risk group. CONCLUSION: Optic flow stimuli have a generalised destabilising effect on postural control across groups as shown by non-directional specific increases in postural sway and muscular activity. Optic flow stimuli have a greater impact on postural stability in older compared with younger adults and this is more pronounced in the ML plane for older people at increased risk of falls.

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.

Impact of pathological conditions on postural reflex latency and adaptability following unpredictable perturbations: A systematic review and meta-analysis.

BACKGROUND: Pathological conditions can impair responses to postural perturbations and increase risk of falls. RESEARCH QUESTION: To what extent are postural reflexes impaired in people with pathological conditions and can exercise interventions shorten postural reflexes? METHODS: MEDLINE, EMBASE, Scopus, SportDiscus and Web of Science were systematically searched for articles comparing muscle activation onset latency in people with pathological conditions to healthy controls following unpredictable perturbations including the effect of exercise interventions (registration: CRD42020170861). RESULTS: Fifty-three articles were included for systematic review. Significant delays in muscle activity onset following perturbations were evident in people with multiple sclerosis (n = 7, mean difference [MD]: 22 ms, 95% confidence interval [CI]: 11, 33), stroke (n = 10, MD: 34 ms, 95% CI: 19, 49), diabetes (n = 2, MD: 19 ms, 95% CI: 10, 27), HIV (n = 3, MD: 9 ms, 95% CI: 4, 14), incomplete spinal cord injury (n = 2, MD: 57 ms, 95% CI: 33, 80) and back and knee pain (n = 7, MD: 12 ms, 95% CI: 6, 18), but not in people with Parkinson's disease (n = 10) or cerebellar dysfunction (n = 4). Following exercise interventions, the paretic limb of stroke survivors (n = 3) displayed significantly faster muscle activation onset latency compared to pre-exercise (MD: -13 ms, 95% CI: -24, -4), with no significant changes in Parkinson's disease (n = 3). CONCLUSIONS: This systematic review demonstrated that postural reflexes are significantly delayed in people with multiple sclerosis (+22 ms), stroke (+34 ms), diabetes (+19 ms), HIV (+9 ms), incomplete spinal cord injury (+57 ms), back and knee pain (+12 ms); pathological conditions characterized by impaired sensation or neural function. In contrast, timing of postural reflexes was not impaired in people with Parkinson's disease and cerebellar dysfunction, confirming the limited involvement of supraspinal structures. The meta-analysis showed exercise interventions can significantly shorten postural reflex latencies in stroke survivors (-14 ms), but more research is needed to confirm this finding and in people with other pathological conditions.

Appendicular and mid-thigh lean mass are associated with muscle strength, physical performance, and dynamic balance in older persons at high risk of falls.

BACKGROUND: Falls in older persons are associated with muscle mass and strength alterations, which may also affect balance parameters. However, the most appropriate combined approach to assess muscle and balance components that predict falls in older persons is still lacking. RESEARCH QUESTION: We hypothesized that appendicular lean and/or mid-thigh mass and muscle strength and performance are positively associated with balance indices and fall risk in older persons. METHODS: Cross-sectional analyses of retrospective data from 260 participants with risk and/or history of falls examined at a Falls and Fracture Clinic. Assessments included a comprehensive clinical exam, bone densitometry and body composition by DXA, grip strength, gait speed, posturography, timed up and go (TUG) and four-square step (FSST) tests. Retrospective falls and fracture history was collected. Associations between appendicular and mid-thigh lean mass and muscle strength/performance vs balance indicators were determined before and after adjusting for age and gender. RESULTS: Mean age of participants was 78 ± 6.7 (65-96) years. Both appendicular and mid-thigh lean masses corrected for BMI (but not for height2), and muscle strength and performance measures are associated with better dynamic balance. Conversely, static balance indicators showed less consistent associations with lean mass. Only TUG and sit to stand time consistently showed significant associations with most static balance indicators. SIGNIFICANCE: Combined with strength and performance parameters, ALM and mid-thigh estimates adjusted by BMI strongly correlate with dynamic balance parameters and could become practical elements of falls risk assessment as well as markers of therapeutic response to falls prevention interventions.

Association between Circulating Osteoprogenitor Cells and Sarcopenia.

BACKGROUND: Circulating osteoprogenitor (COP) cells are a surrogate of the bone marrow mesenchymal stem cells with high levels observed in osteoporosis and the initial stages of fracture healing. Conversely, a low percentage of COP cells (%COP) is strongly associated with frailty and disability. However, it is unknown whether %COP is associated with sarcopenia, a musculoskeletal disease closely related to frailty. OBJECTIVES: This study sought to determine the associations between %COP and sarcopenia defined using the Sarcopenia Definitions and Outcomes Consortium (SDOC) criteria. METHODS: Data from a random sample of 73 community-dwelling older persons enrolled in the Nepean Osteoporosis and Frailty study (median age 74 years; 60% female) were analyzed. %COP was quantified by flow cytometry using selective gating of CD45/osteocalcin (OCN) + cells. Sarcopenia was defined using handgrip strength and gait speed with cut points as per the SDOC criteria. Linear regression was used for analysis. RESULTS: Sarcopenia was identified in 19% of participants, all of whom were frail. After adjusting for age, sex, and interleukin 6, sarcopenic participants had 36% lower %COP (95% confidence interval [CI] -56%, -6%, p = 0.024). Both grip strength and gait speed showed associations with %COP (p = 0.065 and 0.002, respectively); however, after adjusting for age and frailty, only gait speed remained associated with %COP (0.1 m/s increase in gait velocity was associated with a 5% increase in %COP cells (95% CI 0%, 10%, p = 0.052). CONCLUSIONS: High levels of %COP are associated with better muscle function. Future longitudinal studies are required to elucidate the clinical utility of %COP as a potential biomarker or disease stratifier for sarcopenia.

Frailty in Stroke-A Narrated Review.

This narrative review provides a summary introduction to the relationship between stroke and physical and cognitive frailty syndromes and the neuro-inflammatory similarities (including inflammaging) between the two. The review argues the potential effects of Post COVID-19 Neurological Syndrome (PCNS, also known as Long COVID) with similar pathophysiology. Many patients who have suffered from acute stroke experience long-lasting symptoms affecting several organs including fatigue, brain fog, reduced physical activity, loss of energy, and loss of cognitive reserve, culminating in the loss of independence and poor quality of life. This is very similar to the emerging reports of PCNS from different parts of the world. Stroke, particularly in older adults with comorbidities appears to impact the health and welfare of patients by reducing central neuronal input and neuromuscular function, with muscular atrophy and neuropsychiatric complications. The cumulative effects can potentially lead to a range of physical and cognitive frailty syndromes, which, in many cases may be attributed to persistent, maladapted, low grade, chronic inflammation. Meanwhile, post-COVID-19 Neurological Syndrome (also known as Long COVID Syndrome) appears to share a similar trajectory, adding further urgency for investigations into the mechanisms underlying this constellation of symptoms.

Prevalence of Sarcopenia and its Association with Antirheumatic Drugs in Middle-Aged and Older Adults with Rheumatoid Arthritis: A Systematic Review and Meta-analysis.

To examine the prevalence of sarcopenia and its association with antirheumatic drugs in adults with rheumatoid arthritis (RA). This review was registered on PROSPERO and followed PRISMA guidelines. Electronic databases were searched for studies reporting on the prevalence of sarcopenia in adults with RA using any muscle index (muscle mass, strength and/or physical performance) and cutpoints as recommended by established criteria (EWGSOP1/2, AWGS, FNIH, SDOC). The secondary objective was to investigate the relationship between RA, antirheumatic drugs, and sarcopenia. Among 2240 middle-aged and older adults with RA (mean age: 47.7 ± 5.5 to 75.0 ± 6.2 years, 83.8% women), the pooled prevalence of low muscle mass/sarcopenia was 30.2% [95% confidence interval (CI) 24.2-36.2%; 16 studies; I2: 89.2%]. Sub-group analysis showed a non-significant higher prevalence of low muscle mass alone (32.6%, 95% CI 25.0-40.3%; I2: 87.9%) versus consensus definitions of sarcopenia (25.4%, 95% CI 15.4-35.3%; I2: 91.2%, p = 0.255). In adults with RA, corticosteroid use was positively associated with sarcopenia [odds ratio (OR) 1.46, 95% CI 0.94-2.29, 7 studies; I2: 47.5%] while conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) was inversely associated (OR 0.70, 95% CI 0.52-0.94; 6 studies: I2: 0.00%) with this muscle disease. No association was found for biological/targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) (OR 0.83, 95% CI 0.54-1.30; 6 studies: I2: 47.6%). Sarcopenia is a common comorbidity of RA, and as such, clinicians should screen for this muscle disease in adults with RA. Further longitudinal studies are needed to understand the role of antirheumatic drugs (particularly type, dosing, and duration) in the development of sarcopenia.

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.

The prevention of osteoporosis and sarcopenia in older adults.

Osteoporosis and sarcopenia are common in older adults. Osteoporosis is a systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture. Bone fractures can result in changes in posture, pain, the need for surgical repair and functional impairment. Sarcopenia is the progressive and generalized loss of skeletal muscle mass, strength and/or physical performance. Older adults with sarcopenia experience increased risk of frailty, disability, hospitalizations, mortality, and a reduced quality of life. In this narrative review we provide guidance regarding the prevention of both osteoporosis and sarcopenia, including interventions that prevent both conditions from occurring, recommended screening and treatment to prevent progression.

Education, occupation and operational measures of sarcopenia: Six years of Australian data.

OBJECTIVES: To examine associations of education and occupation with handgrip strength (HGS), lower limb strength (LLS) and appendicular lean mass (ALM). METHODS: Measures of HGS, LLS and ALM (dual-energy X-ray absorptiometry) were ascertained at baseline in 1090 adults (50-80 years, 51% women), ~3 and 5 years. Education and occupation were self-reported, the latter categorised as high-skilled white collar (HSWC), low-skilled white collar (LSWC) or blue collar. Separate general estimating equations were performed. RESULTS: The highest education group had greater HGS than the middle (0.33 psi) and lowest (0.48 psi) education groups, and 0.34 kg greater ALM than the lowest education group. HGS was 0.46 psi greater for HSWC than LSWC groups. Compared to LSWC groups, LLS was 5.38 and 7.08 kg greater in HSWC and blue-collar groups. Blue-collar and HSWC groups each had ~ 0.60-0.80kg greater ALM than LSWC. CONCLUSION: Progressive muscle loss can be prevented by targeted intervention; thus, we suggest clinical attention be directed towards specific social groups.

Diagnosis, prevalence, and clinical impact of sarcopenia in COPD: a systematic review and meta-analysis.

Sarcopenia prevalence and its clinical impact are reportedly variable in chronic obstructive pulmonary disease (COPD) due partly to definition criteria. This review aimed to identify the criteria used to diagnose sarcopenia and the prevalence and impact of sarcopenia on health outcomes in people with COPD. This review was registered in PROSPERO (CRD42018092576). Five electronic databases were searched to August 2018 to identify studies related to sarcopenia and COPD. Study quality was assessed using validated instruments matched to study designs. Sarcopenia prevalence was determined using authors' definitions. Comparisons were made between people who did and did not have sarcopenia for pulmonary function, exercise capacity, quality of life, muscle strength, gait speed, physical activity levels, inflammation/oxidative stress, and mortality. Twenty-three studies (70% cross-sectional) from Europe (10), Asia (9), and North and South America (4) involving 9637 participants aged ≥40 years were included (69.5% men). Sarcopenia criteria were typically concordant with recommendations of hEuropean and Asian consensus bodies. Overall sarcopenia prevalence varied from 15.5% [95% confidence interval (CI) 11.8-19.1; combined muscle mass, strength, and/or physical performance criteria] to 34% (95%CI 20.6-47.3; muscle mass criteria alone) (P = 0.009 between subgroups) and was greater in people with more severe [37.6% (95%CI 24.8-50.4)] versus less severe [19.1% (95%CI 10.2-28.0)] lung disease (P = 0.020), but similar between men [41.0% (95%CI 26.2-55.9%)] and women [31.9% (95%CI 7.0-56.8%)] (P = 0.538). People with sarcopenia had lower predicted forced expiratory volume in the first second (mean difference -7.1%; 95%CI -9.0 to -5.1%) and poorer exercise tolerance (standardized mean difference -0.8; 95%CI -1.4 to -0.2) and quality of life (standardized mean difference 0.26; 95%CI 0.2-0.4) compared with those who did not (P < 0.001 for all). No clear relationship was observed between sarcopenia and inflammatory or oxidative stress biomarkers. Incident mortality was unreported in the literature. Sarcopenia is prevalent in a significant proportion of people with COPD and negatively impacts upon important clinical outcomes. Opportunities exist to optimize its early detection and management and to evaluate its impact on mortality in this patient group.

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.

Age-Related Increases in Marrow Fat Volumes have Regional Impacts on Bone Cell Numbers and Structure.

The increasing levels of bone marrow fat evident in aging and osteoporosis are associated with low bone mass and attributed to reduced osteoblastogenesis. Local lipotoxicity has been proposed as the primary mechanism driving this reduction in bone formation. However, no studies have examined the correlation between high levels of marrow fat volumes and changes in local cellularity. In this study, we hypothesize that areas of bone marrow with high fat volumes are associated with significant changes in cell number within a similar region of interest (ROI). Inbred albino Louvain (LOU) rats, originating from the Wistar strain, have been described as a model of healthy aging with the absence of obesity but expressing the typical features of age-related bone loss. We compared local changes in distal femur cellularity and structure in specific ROI of undecalcified bone sections from 4- and 20-month-old male and female LOU rats and Wistar controls. Our results confirmed that older LOU rats exhibited significantly higher fat volumes than Wistar rats (p < 0.001). These higher fat volume/total volume were associated with lower trabecular number (p < 0.05) and thickness (p < 0.05) and higher trabecular separation (p < 0.05). In addition, osteoblast and osteocyte numbers were reduced in the similar ROI containing high levels of adiposity, while osteoclast number was higher compared to control (p < 0.03). In summary, marrow ROIs with a high level of adiposity were associated with a lower bone mass and changes in cellularity explaining associated bone loss. Further studies assessing the levels of lipotoxicity in areas of high local marrow adiposity and identifying molecular actors involved in this phenomenon are still required.

Associations between osteoporosis, the severity of sarcopenia and fragility fractures in community-dwelling older adults.

PURPOSE: To investigate the association between bone mineral density (BMD) and the severity of sarcopenia using the revised European Working Group on Sarcopenia in Older People (EWGSOP2) definition. METHODS: BMD [dual energy X-ray absorptiometry (DXA)], appendicular lean mass (DXA), handgrip strength (hydraulic dynamometer) and gait speed (over 4-m) were used to screen for osteoporosis and sarcopenia. Participants were categorized as osteoporotic according to the World Health Organization definition (T score ≤ - 2.5), and classified with probable sarcopenia or confirmed sarcopenia according to the EWGSOP2 criteria. Fasting biochemistry profile, fragility fractures, malnutrition index, geriatric depression scale and fear of falling, were also measured using validated procedures. RESULTS: A total of 484 community-dwelling older adults (69.6% women) with a median age of 76 years [Interquartile range (IQR) 70-81] were included in this study. Osteoporosis prevalence increased from 47.6% in non-sarcopenia to 65.5% in probable sarcopenia and 78.1% in those with confirmed sarcopenia (p < 0.05). After adjusting for age, sex and vitamin D in multivariate models, osteoporosis was associated with a greater risk of confirmed sarcopenia [odds ratio (OR) 2.885, 95% CI 1.155, 7.204, p = 0.023]. The number of fragility fractures was also higher in those with confirmed sarcopenia versus those without (p = 0.013), but this finding did not remain significant in adjusted models (p = 0.078). CONCLUSION: Prevalence of osteoporosis increased across the severity of sarcopenia, and osteoporosis was associated with a greater risk of sarcopenia. As such, health care professionals should screen for sarcopenia in those with low BMD.

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.

Osteocalcin and its forms across the lifespan in adult men.

PURPOSE: Osteocalcin (OC), an osteoblast-specific secreted protein expressed by mature osteoblasts, is used in clinical practice and in research as a marker of bone turnover. The carboxylated (cOC) and undercarboxylated (ucOC) forms may have a different biological function but age-specific reference ranges for these components are not established. Given the different physiological roles, development of reference ranges may help to identify people at risk for bone disease. METHODS: Blood was collected in the morning after an overnight fast from 236 adult men (18 to 92 years old) free of diabetes, antiresorptive, warfarin or glucocorticoid use. Serum was analyzed for total osteocalcin (tOC) and the ucOC fraction using the hydroxyapatite binding method. cOC, ucOC/tOC and cOC/tOC ratios were calculated. Reference intervals were established by polynomial quantile regression analysis. RESULTS: The normal ranges for young men (≤30 years) were: tOC 17.9-56.8 ng/mL, ucOC 7.1-22.0 ng/mL, cOC 8.51-40.3 ng/mL (2.5th to 97.5th quantiles). Aging was associated with a "U" shaped pattern for tOC, cOC and ucOC levels. ucOC/tOC ratio was higher, while cOC/tOC ratio was lower in men of advanced age. Age explained ∼31%, while body mass index explained ∼4%, of the variance in the ratios. CONCLUSIONS: We have defined normal reference ranges for the OC forms in Australian men and demonstrated that the OC ratios may be better measures, than the absolute values, to identify the age-related changes on OC in men. These ratios may be incorporated into future research and clinical trials, and their associations with prediction of events, such as fracture or diabetes risk, should be determined.

Balance training using virtual reality improves balance and physical performance in older adults at high risk of falls.

PURPOSE: Exercise programs designed for falls prevention have been proven effective in reducing falls by approximately 21%. Virtual reality may provide a viable alternative intervention for falls prevention. This study compared the effects of virtual reality training using the Balance Rehabilitation Unit (BRU) versus exercise using a modified Otago Exercise Programme (EX) on improving balance and physical performance in the short-term restorative care setting of the Gait and Balance Gym (Gabagym). PATIENTS AND METHODS: This was a pre- and post-intervention study of 195 participants (median age 78 years, IQR 73-84; 67% female) who presented with a risk and/or history of falls. Participants were assigned to either EX (n=82) or BRU (n=63). Supervised sessions occurred twice a week for 6 weeks. Participants receiving interventions were compared to a separate group (n=50) with similar characteristics who did not receive any intervention. Balance and physical performance were assessed at initial and final attendance and included the 5 Times Sit to Stand (5STS) test, Timed Up and Go (TUG), gait speed and posturography assessment using the BRU. Fear of falling was assessed using the Falls Efficacy Scale. Handgrip strength and adherence were also monitored. RESULTS: Post-intervention, EX and BRU groups achieved similar improvements and reported similar adherence rates (71% vs 72%, respectively). Both intervention groups improved in balance and physical performance measures. Both interventions showed significantly better improvement than the non-intervention group in TUG (p<0.001), gait speed (p=0.021), limits of stability in posturography assessment (p=0.008), FES-I score (p=0.013) and handgrip strength (p=0.021). Only the BRU group improved control of static posture in the eyes closed (p=0.002) and foam eyes closed (p=0.006) tasks. CONCLUSION: This study highlights the potential use of virtual reality as a practical alternative to improve outcomes of balance training for reduction of falls risk in older adults.