Normative Data for Lean Mass Using FNIH Criteria in an Australian Setting

Safety, Feasibility, and Acceptability of a Multisite Individualized Exercise Intervention for People with Multiple Myeloma

INTRODUCTION

High rates of disease- and treatment-related symptoms, such as bone lesions, in people with multiple myeloma (MM) create uncertainty on the safety and feasibility of exercise. This study determined the safety, feasibility, and acceptability of an individualized exercise medicine program for people with MM at any disease stage.

METHODS

A multisite, randomized waitlist-controlled trial was conducted of an individualized, high-intensity aerobic, resistance, and impact-loading exercise program. The exercise sessions were supervised twice weekly by accredited exercise physiologists, with one additional unsupervised session per week, for 12 wk. Safety was determined by number of adverse and serious adverse events. Feasibility outcome measures were study eligibility, recruitment, adherence, and attrition. Acceptability was determined by qualitative interviews and subjective levels of enjoyment.

RESULTS

Of 203 people with MM screened, 88% were eligible, with 34% accepting participation (60 people) and 20% attrition for the between-group analysis, meeting a priori criteria (≥25% and <25%, respectively). No adverse or serious adverse events attributed to testing and/or exercise training were reported. Attendance at supervised exercise sessions was 98%, with 45% completion of the home-based exercise sessions. Adherence rates were 35%, 63%, and 34% for the aerobic, resistance, and impact-loading protocols, with 55%, 80%, and 37% of participants meeting a priori criteria (75% of protocol). Acceptability of the exercise program was high (mean, 82%; 95% confidence interval, 78%-87%) and highly supported by qualitative responses.

CONCLUSIONS

An individualized, high-intensity aerobic, resistance, and impact-loading exercise medicine program is safe and acceptable, and feasible by some measures for people with MM. Adherence to the prescribed exercise protocols was limited by comorbidities and disease symptoms. Strategies to improve unsupervised exercise completion are warranted in this population.

The longitudinal associations of sarcopenia definitions with functional deterioration: a comparative study

OBJECTIVE

Probable sarcopenia is a predictor of functional limitation in older adults. However, whether standard thresholds recommended by guides, or population-specific thresholds better predict impairment in functionality is an issue that needs to be enlightened. We aimed to study the associations of probable sarcopenia identified by the use of EWGSOP2 and population-specific thresholds with deterioration in functionality at follow-up and give prevalences of probable sarcopenia with different thresholds in older outpatients admitted to a tertiary health center.

METHODS

In this retrospective, longitudinal follow-up study, we assessed handgrip strength (HGS) at the admission with a Jamar hand-dynamometer and diagnosed probable sarcopenia with standard and population-specific thresholds, i.e., 27 kg/16 kg, and 35 kg/20 kg in males/females, respectively. We evaluated activities of daily living (ADL) and instrumental ADL (IADL), with Katz and Lawton scales, at the admission and follow-up. To study whether probable sarcopenia was a predictor of impaired functionality, we defined two models for Cox regression analysis. We performed adjustments for age, sex, and nutritional status (assessed by Mini-Nutritional Assessment-Short Form) in Model 1 and defined Model 2 by adding low gait speed and frailty to the variables in Model 1.

RESULTS

Among a total of 1970 patients, 195 had follow-up of median 560 days. The mean age was 75.5 ± 5.5, and 142 (72.8%) were female. In the basal evaluation, the prevalences of probable sarcopenia defined by the standard cut-offs and by population-specific cut-offs were 8.7% and 35.4%, respectively. In univariate analyses (Kaplan-Meier log-rank test), probable sarcopenia by population-specific cut-offs, but not EWGSOP2-cut-offs, was associated with deteriorations in both ADL (p = 0.04) and IADL (p < 0.001). In multivariate analyses, only the probable sarcopenia identified by population-specific cut-offs was independently associated with impairment in IADL in both models [HR (95%CI) = 1.88 (1.07-3.30), and 1.9 (1.04-3.6); for Model 1 and Model 2, respectively)].

CONCLUSION

Our findings suggested that the definition of probable sarcopenia identified by not standard, but population-specific thresholds more reliably predicted longitudinal deterioration of functionality in older outpatients. This finding might be considered as evidence supporting the use of population-specific cut-offs when the concern is sarcopenia diagnosis.

Guidance for assessment of the muscle mass phenotypic criterion for the Global Leadership Initiative on Malnutrition diagnosis of malnutrition

The Global Leadership Initiative on Malnutrition (GLIM) provides consensus criteria for the diagnosis of malnutrition that can be widely applied. The GLIM approach is based on the assessment of three phenotypic (weight loss, low body mass index, and low skeletal muscle mass) and two etiologic (low food intake and presence of disease with systemic inflammation) criteria, with diagnosis confirmed by any combination of one phenotypic and one etiologic criterion fulfilled. Assessment of muscle mass is less commonly performed than other phenotypic malnutrition criteria, and its interpretation may be less straightforward, particularly in settings that lack access to skilled clinical nutrition practitioners and/or to body composition methodologies. In order to promote the widespread assessment of skeletal muscle mass as an integral part of the GLIM diagnosis of malnutrition, the GLIM consortium appointed a working group to provide consensus-based guidance on assessment of skeletal muscle mass. When such methods and skills are available, quantitative assessment of muscle mass should be measured or estimated using dual-energy x-ray absorptiometry, computerized tomography, or bioelectrical impedance analysis. For settings where these resources are not available, then the use of anthropometric measures and physical examination are also endorsed. Validated ethnic- and sex-specific cutoff values for each measurement and tool are recommended when available. Measurement of skeletal muscle function is not advised as surrogate measurement of muscle mass. However, once malnutrition is diagnosed, skeletal muscle function should be investigated as a relevant component of sarcopenia and for complete nutrition assessment of persons with malnutrition.

How Well Do Low Population-Specific Values for Muscle Parameters Associate with Indices of Poor Physical Health? Cross-Sectional Data from the Geelong Osteoporosis Study

We aimed to examine associations between skeletal muscle deficits and indices of poor health. Cut-points for skeletal muscle deficits were derived using data from the Geelong Osteoporosis Study and definitions from the revised European Consensus on Definition and Diagnosis and the Foundation for the National Institutes of Health. Participants (n = 665; 323 women) aged 60–96 year had handgrip strength measured by dynamometry and appendicular lean mass by whole-body dual-energy X-ray absorptiometry. Physical performance was assessed using the Timed Up and Go test. Sex-specific cut-points were equivalent to two standard deviations below the mean young reference range from the Geelong Osteoporosis Study. Indices of poor health included fractures, falls, and hospitalisations. Low trauma fractures since age 50 year (excluding skull, face, digits) were self-reported and confirmed using radiological reports. Falls (≥1 in the past 12 months) and hospitalisations (past month) were self-reported. Logistic regression models (age- and sex-adjusted) were used to examine associations. Receiver Operating Characteristic curves were applied to determine optimal cut-points for handgrip strength, Timed Up and Go, appendicular lean mass/height2, and appendicular lean mass/body mass index that discriminated poor health outcomes. There were 48 participants (6.9%) with hospitalisations, 94 (13.4%) with fractures, and 177 (25.3%) with at least one fall (≥1). For all cut-points, low handgrip strength was consistently associated with falls. There was little evidence to support an association between low appendicular lean mass, using any cut-point, and indices of poor health. Optimal cut-offs for predicting falls (≥1) were: handgrip strength 17.5 kg for women and 33.5 kg for men; Timed Up and Go 8.6 s for women and 9.9 s for men; appendicular lean mass/height2 6.2 kg/m2 for women and 7.46 kg/m2 for men; and appendicular lean mass/body mass index 0.6 m2 for women and 0.9 m2 for men. In conclusion, muscle strength and function performed better than lean mass to indicate poor health. These findings add to the growing evidence base to inform decisions regarding the selection of skeletal muscle parameters and their optimal cut-points for identifying sarcopenia.

Guidance for assessment of the muscle mass phenotypic criterion for the Global Leadership Initiative on Malnutrition (GLIM) diagnosis of malnutrition

The Global Leadership Initiative on Malnutrition (GLIM) provides consensus criteria for the diagnosis of malnutrition that can be widely applied. The GLIM approach is based on the assessment of three phenotypic (weight loss, low body mass index, and low skeletal muscle mass) and two etiologic (low food intake and presence of disease with systemic inflammation) criteria, with diagnosis confirmed by any combination of one phenotypic and one etiologic criterion fulfilled. Assessment of muscle mass is less commonly performed than other phenotypic malnutrition criteria, and its interpretation may be less straightforward, particularly in settings that lack access to skilled clinical nutrition practitioners and/or to body composition methodologies. In order to promote the widespread assessment of skeletal muscle mass as an integral part of the GLIM diagnosis of malnutrition, the GLIM consortium appointed a working group to provide consensus-based guidance on assessment of skeletal muscle mass. When such methods and skills are available, quantitative assessment of muscle mass should be measured or estimated using dual-energy x-ray absorptiometry, computerized tomography, or bioelectrical impedance analysis. For settings where these resources are not available, then the use of anthropometric measures and physical examination are also endorsed. Validated ethnic- and sex-specific cutoff values for each measurement and tool are recommended when available. Measurement of skeletal muscle function is not advised as surrogate measurement of muscle mass. However, once malnutrition is diagnosed, skeletal muscle function should be investigated as a relevant component of sarcopenia and for complete nutrition assessment of persons with malnutrition.

Estimation of Whole-Body and Appendicular Lean Mass from Spine and Hip Dual Energy X-ray Absorptiometry: A Cross-Sectional Study

Whole-body dual X-ray absorptiometry (DXA) accurately measures lean mass but is not routinely used in clinical practice. Hip and spine DXA are used in the diagnosis of osteoporosis, and with the common co-occurrence of sarcopenia with osteoporosis, regional DXA scans provide an opportunity for assessment of lean mass. The aim of this study is to develop predictive equations for the estimation of whole-body lean mass (WBLM), appendicular lean mass (ALM) and whole-body fat mass (WBFM) from regional DXA scans. A total of 2427 participants (ages 20-96 year; 57.7% men) from the Geelong Osteoporosis Study who underwent both regional and whole-body DXA were included in the analysis. Using forward stepwise multivariable linear regression, percentage fat (spine%fat, hip%fat) values from lumbar spine and femoral neck DXA were used in combination with clinical data to develop and validate equations for the estimation of WBLM, WBFM and ALM. Mean age was 53.5 year (± 19.2), weight 78.2 kg (± 15.4), height 169.6 cm (± 9.4), WBLM 50.4 kg (± 11.1), ALM 22.8 kg (± 5.4) and WBFM 24.3 kg (± 10.4). Spine%fat (r = 0.21) and hip%fat (r = - 0.34) were correlated with whole-body lean mass (p < 0.001). Final predictive equations included age, sex, weight, height, spine%fat, and hip%fat and possessed high predictive value (Adj R² 0.91-0.94, RMSE 1.60-2.84 kg). K-fold cross-validation methods produced median root mean square error (RMSE) ranging from 1.59 to 2.81 kg for the three models. Regional DXA scans of the spine and hip can be used to estimate whole-body and appendicular lean mass, to assist in the identification of low muscle mass.

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.

Prevalence of Sarcopenia Employing Population-Specific Cut-Points: Cross-Sectional Data from the Geelong Osteoporosis Study, Australia

Background: Prevalence estimates for sarcopenia vary depending on the ascertainment criteria and thresholds applied. We aimed to estimate the prevalence of sarcopenia using two international definitions but employing Australian population-specific cut-points. Methods: Participants (n = 665; 323 women) aged 60–96 years old were from the Geelong Osteoporosis Study. Handgrip strength (HGS) was measured by dynamometers and appendicular lean mass (ALM) by whole-body dual-energy X-ray absorptiometry. Physical performance was assessed using gait speed (GS, men only) and/or the timed up-and-go (TUG) test. Using cut-points equivalent to two standard deviations (SDs) below the mean young reference range from the same population and recommendations from the European Working Group on Sarcopenia in Older People (EWGSOP), sarcopenia was identified by low ALM/height² (<5.30 kg for women; <6.94 kg for men) + low HGS (<16 kg women; <31 kg men); low ALM/height² + slow TUG (>9.3 s); low ALM/height² + slow GS (<0.8 m/s). For the Foundation for the National Institutes of Health (FNIH) equivalent, sarcopenia was identified as low ALM/BMI (<0.512 m² women, <0.827 m² men) + low HGS (<16 kg women, <31 kg men). Receiver Operating Characteristic curves were also applied to determine optimal cut-points for ALM/BMI (<0.579 m² women, <0.913 m² men) that discriminated poor physical performance. Prevalence estimates were standardized to the Australian population and compared to estimates using international thresholds. Results: Using population-specific cut-points and low ALM/height² + HGS, point-estimates for sarcopenia prevalence were 0.9% for women and 2.9% for men. Using ALM/height² + TUG, prevalence was 2.5% for women and 4.1% for men, and using ALM/height² + GS, sarcopenia was identified for 1.6% of men. Using ALM/BMI + HGS, prevalence estimates were 5.5–10.4% for women and 11.6–18.4% for men. Conclusions: This study highlights the range of prevalence estimates that result from employing different criteria for sarcopenia. While population-specific criteria could be pertinent for some populations, a consensus is needed to identify which deficits in skeletal muscle health are important for establishing an operational definition for sarcopenia.

Skeletal Muscle Health and Cognitive Function: A Narrative Review

Sarcopenia is the loss of skeletal muscle mass and function with advancing age. It involves both complex genetic and modifiable risk factors, such as lack of exercise, malnutrition and reduced neurological drive. Cognitive decline refers to diminished or impaired mental and/or intellectual functioning. Contracting skeletal muscle is a major source of neurotrophic factors, including brain-derived neurotrophic factor, which regulate synapses in the brain. Furthermore, skeletal muscle activity has important immune and redox effects that modify brain function and reduce muscle catabolism. The identification of common risk factors and underlying mechanisms for sarcopenia and cognition may allow the development of targeted interventions that slow or reverse sarcopenia and also certain forms of cognitive decline. However, the links between cognition and skeletal muscle have not been elucidated fully. This review provides a critical appraisal of the literature on the relationship between skeletal muscle health and cognition. The literature suggests that sarcopenia and cognitive decline share pathophysiological pathways. Ageing plays a role in both skeletal muscle deterioration and cognitive decline. Furthermore, lifestyle risk factors, such as physical inactivity, poor diet and smoking, are common to both disorders, so their potential role in the muscle-brain relationship warrants investigation.

Lower-limb muscle strength: normative data from an observational population-based study

BACKGROUND

The extent of muscle deterioration associated with ageing or disease can be quantified by comparison with appropriate reference data. The objective of this study is to present normative data for lower-limb muscle strength and quality for 573 males and 923 females aged 20-97 yr participating in the Geelong Osteoporosis Study in southeastern Australia.

METHODS

In this cross-sectional study, measures of muscle strength for hip flexors and hip abductors were obtained using a Nicholas manual muscle tester, a hand-held dynamometer (HHD; kg). Leg lean mass was measured by dual energy x-ray absorptiometry (DXA; kg), and muscle quality calculated as strength/mass (N/kg).

RESULTS

For both sexes, muscle strength and quality decreased with advancing age. Age explained 12.9-25.3% of the variance in muscle strength in males, and 20.8-24.6% in females; age explained less of the variance in muscle quality. Means and standard deviations for muscle strength and quality for each muscle group are reported by age-decade for each sex, and cutpoints equivalent to T-scores of - 2.0 and - 1.0 were derived using data from young males (n = 89) and females (n = 148) aged 20-39 years.

CONCLUSIONS

These data will be useful for quantifying the extent of dynapenia and poor muscle quality among adults in the general population in the face of frailty, sarcopenia and other age-related muscle dysfunction.