Relationships Between Level and Change in Sarcopenia and Other Body Composition Components and Adverse Health Outcomes: Findings from the Health, Aging, and Body Composition Study

Sarcopenia-related traits and risk of falls in older adults: results from meta-analysis of cohort studies and Mendelian randomization analyses

BACKGROUND

Observational studies examining sarcopenia-related traits and fall risk remain controversial. Herein, we conducted meta-analyses of cohort studies triangulated with Mendelian randomization (MR) analyses to examine the potential causality between sarcopenia-related traits and risk of falls in older adults.

METHODS

Literature search across PubMed, Embase, and Cochrane Library was performed from inception to February 2023 to identify cohort studies examining sarcopenia-related traits (including hand strength, appendicular lean mass, and walking speed) and falls. We assessed the association between these traits and fall risk using random-effects models to calculate pooled odds ratios (OR) and 95% confidence intervals (CIs). MR analyses were conducted using summary statistics derived from the UK Biobank consortium for sarcopenia-related traits and FinnGen consortium for falls. The inverse-variance weighted method was used as primary analysis.

RESULTS

Our meta-analysis included 34 cohort studies. The combined analysis of sarcopenia-related traits revealed a 33% reduced fall risk with each unit increase in walking speed (OR 0.67, 95% CI 0.54-0.84) and a 2% decrease with each unit increase in hand strength (OR 0.98, 95% CI 0.97-0.99). However, appendicular lean mass had no significant effect on falls. In the MR analyses, only walking speed was causally associated with falls (OR 0.64, 95% CI 0.48-0.84). Hand strength and appendicular lean mass showed no statistically significant causal effect on falls.

CONCLUSION

Evidence from meta-analysis and MR suggests a strong association between walking speed and fall risk in older adults. However, the relationship between hand strength, appendicular lean mass, and falls has not yet been established.

Prevalence of Polypharmacy in Elderly Population Worldwide: A Systematic Review and Meta-Analysis

BACKGROUND

Polypharmacy (PP) is common in elderly population and associated with some adverse clinical outcomes and increases healthcare burdens. We performed this systemic review and meta-analysis to estimate worldwide prevalence of PP and explore associated factors in the elderly.

METHODS

The PubMed, Web of Science, Cochrane Library, and Ovid EMBASE databases were searched for studies published until May 30, 2022. We included observational studies representative of general patients aged ≥60 in which PP was defined as multiple drugs ≥5. Studies were excluded if only a particular group of the elderly population (e.g., with diabetes) were included. The primary outcome was the prevalence of PP. Random-effect models were employed to estimate the overall or variable-specific pooled estimates of PP. Secondary outcomes were hyperpolypharmacy (HPP, defined as multiple drugs ≥10) and PP prevalence based on different study years, genders, locations, populations, and so forth.

RESULTS

We included 122 original observational studies with an overall population of 57 328 043 individuals in the meta-analysis. The overall prevalence of PP and HPP in the elderly population worldwide was 39.1% (95% confidence interval [CI], 35.5%-42.7%) and 13.3% (95% CI, 10.4%-16.5%), respectively. The prevalence of PP in Europe, Oceania, North America, Asia, and South America was 45.8% (95% CI, 41.5%-50.2%), 45.5% (95% CI, 26.7%-64.3%), 40.8% (95% CI, 29.8%-51.6%), 29.0% (95% CI, 20.0%-38.0%), and 28.4% (95% CI, 24.0%-32.8%), respectively (p < 0.01). Multivariate meta-regressions showed geographical regions of Europe or North America, age ≥70, and residence from nursing homes were independently associated with higher PP prevalence.

CONCLUSIONS

Nearly 40% of the elderly population is exposed to PP. The prevalence of PP is significantly higher in elderly individuals aged 70 or older, in developed regions and in nursing homes. It is important to focus on avoiding inappropriate PP in this population to address the growing burden of PP.

Muscle parameters in fragility fracture risk prediction in older adults: A scoping review

Half of osteoporotic fractures occur in patients with normal/osteopenic bone density or at intermediate or low estimated risk. Muscle measures have been shown to contribute to fracture risk independently of bone mineral density. The objectives were to review the measurements of muscle health (muscle mass/quantity/quality, strength and function) and their association with incident fragility fractures and to summarize their use in clinical practice. This scoping review follows the PRISMA-ScR guidelines for reporting. Our search strategy covered the three overreaching concepts of 'fragility fractures', 'muscle health assessment' and 'risk'. We retrieved 14 745 references from Medline Ovid SP, EMBASE, Web of Science Core Collection and Google Scholar. We included original and prospective studies on community-dwelling adults aged over 50 years that analysed an association between at least one muscle parameter and incident fragility fractures. We systematically extracted 17 items from each study, including methodology, general characteristics and results. Data were summarized in tables and graphically presented in adjusted forest plots. Sixty-seven articles fulfilled the inclusion criteria. In total, we studied 60 muscle parameters or indexes and 322 fracture risk ratios over 2.8 million person-years (MPY). The median (interquartile range) sample size was 1642 (921-5756), age 69.2 (63.5-73.6) years, follow-up 10.0 (4.4-12.0) years and number of incident fragility fractures 166 (88-277). A lower muscle mass was positively/not/negatively associated with incident fragility fracture in 28 (2.0), 64 (2.5) and 10 (0.2 MPY) analyses. A lower muscle strength was positively/not/negatively associated with fractures in 53 (1.3), 57 (1.7 MPY) and 0 analyses. A lower muscle function was positively/not/negatively associated in 63 (1.9), 45 (1.0 MPY) and 0 analyses. An in-depth analysis shows how each single muscle parameter was associated with each fragility fractures subtype. This review summarizes markers of muscle health and their association with fragility fractures. Measures of muscle strength and function appeared to perform better for fracture risk prediction. Of these, hand grip strength and gait speed are likely to be the most practical measures for inclusion in clinical practice, as in the evaluation of sarcopenia or in further fracture risk assessment scores. Measures of muscle mass did not appear to predict fragility fractures and might benefit from further research, on D3-creatine dilution test, lean mass indexes and artificial intelligence methods.

Percepciones y experiencias de los adultos mayores con respecto a la actividad Sit-to-stand: Un estudio etnográfico de viabilidad previa

Resumen Objetivo: el propósito de este estudio de viabilidad previa fue examinar percepciones y experiencias con respecto a la actividad Sit-to-stand entre los adultos mayores de Brasil que viven en sus hogares en comunidades urbanas. Método: el método de exploración se enfocó en la etnografía. Se utilizó muestreo intencional para reclutar 20 adultos mayores. Se emplearon cinco medios para generar datos, a saber: encuestas sociodemográficas, observaciones participantes, entrevistas informales, entrevistas formales semiestructuradas y notas de campo. Para el análisis de los datos se recurrió a análisis de contenido cualitativo. Resultados: la experiencia de los adultos mayores con problemas de movilidad en relación con la actividad Sit-to-stand dependió de sus expectativas en torno a la movilidad, las cuales implicaron muchos factores que actuaron en conjunto para influenciar sus creencias y actitudes con respecto a la actividad, al igual que preferencias, conductas y percepciones culturales. Aparentemente, a los participantes de este estudio la actividad les resultó amena; sin embargo, los inconvenientes más notorios para adoptar la actividad Sit-to-stand surgió en la forma de déficits en sus necesidades personales e intrapersonales. Conclusión: las recomendaciones resultantes de los hallazgos del estudio indican la necesidad de diseñar estrategias de implementación para la intervención Sit-to-stand a la medida de las necesidades de este grupo poblacional específico.

Percepções e experiências de idosos com a atividade Sit-to-stand: Um estudo etnográfico de pré-viabilidade

Resumo Objetivo: o objetivo deste estudo de pré-viabilidade foi examinar percepções e experiências da atividade de Sit-to-stand com idosos brasileiros residentes em suas casas, no meio urbano. Método: o método exploratório foi etnografia focada. Foi utilizada a amostragem intencional para recrutar 20 idosos. Foram utilizados cinco meios de geração de dados: inquéritos sociodemográficos, observações participantes, entrevistas informais, entrevistas formais semiestruturadas e notas de campo. Os dados foram analisados mediante análise de conteúdo qualitativo. Resultados: a experiência dos idosos com problemas de mobilidade na realização da atividade Sit-to-stand dependia de suas expectativas de mobilidade envolvendo muitos fatores coordenados que, de forma conjunta, influenciaram suas crenças e atitudes em relação à atividade, suas preferências, seus comportamentos e percepções culturais. Os participantes deste estudo pareciam considerar a atividade aprazível; no entanto, as deficiências mais perceptíveis para o engajamento dos participantes na atividade Sit-to-stand surgiram de falhas em suas necessidades pessoais e intrapessoais. Conclusão: as recomendações geradas a partir dos achados do estudo convocam a concepção de estratégias de implementação da intervenção Sit-to-stand adaptadas às necessidades dessa população em particular.

Influence of 8 Weeks of Tabata High-Intensity Interval Training and Nanocurcumin Supplementation on Inflammation and Cardiorespiratory Health among Overweight Elderly Women

Nanocurcumin (NaC) and high-intensity interval training (HIIT) play crucial role in weight and inflammation control. The purpose of the current study was to evaluate the separate and combined effects of 8 weeks of Tabata-HIIT and NaC supplementation on the NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, long non-coding RNA myocardial infarction associated transcript (lncRNA MIAT) expression, body composition, and cardiorespiratory health in elderly overweight women. A total of 48 healthy overweight elderly women were randomly divided into four groups: NaC, Tabata-HIIT+Pla, Tabata-HIIT+NaC, and placebo. Participants underwent a Tabata HIIT program (2 days per week, at 80∼0% of maximal HR) and NaC supplementation (daily 80 mg in two 40 mg capsules) for 8 weeks. Blood sampling, cardiorespiratory hemodynamic responses, and body composition evaluations were obtained before and after treadmill stress testing at the baseline timepoint and following 8 weeks of intervention. The mRNA of lncRNA-MIAT and NLRP3 were measured by real-time polymerase chain reaction. After 8 weeks, a significant improvement was observed in body composition and cardiorespiratory hemodynamics in the Tabata-HIIT groups compared to the NaC alone and placebo groups (P<0.05). Tabata training, both with and without the addition of nano curcumin supplementation, did not result significant effect on the resting levels of lncRNA-MIAT expression (P>0.05). Nevertheless, NaC supplementation along with Tabata training led to a significant reduction in NLRP3 inflammasome. In addition, NaC supplementation in overweight/preobese women improved systemic inflammation during treadmill stress testing. These findings indicating the suppressive effects of non-pharmacologic interventions on the sympathetic system and downregulation of the inflammasome.

Muscle strength and physical performance contribute to and improve fracture risk prediction in older people: A narrative review

Osteoporotic fractures present a major health problem with an increasing prevalence in older people. Fractures are associated with premature mortality, reduced quality of life, subsequent fracture, and increased costs. Hence, it is crucial to identify those at higher risk of fracture. Fracture risk assessment tools incorporated clinical risk factors to improve fracture predictive power over BMD alone. However, fracture risk prediction using these algorithms remains suboptimal, warranting further improvement. Muscle strength and physical performance measurements have been associated with fracture risk. In contrast, the contribution of sarcopenia, the composite condition of low muscle mass, muscle strength and/or physical performance, to fracture risk is unclear. It is uncertain whether this is due to the problematic definition of sarcopenia per se or limitations of the diagnostic tools and cut-off points of the muscle mass component. The recent position statement from the Sarcopenia Definition and Outcomes Consortium confirmed the inclusion of muscle strength and performance in the definition of sarcopenia but not DXA-assessed lean mass. Therefore, clinicians should focus on functional assessment (muscle strength and performance) rather than muscle mass, at least as assessed by DXA, as predictors of fractures. Muscle strength and performance are modifiable risk factors. Resistance exercise improves muscle parameters in the elderly, potentially leading to reduced risk of falls and fractures in the general population and in those who sustained a fracture. Therapists may consider exercise intervention to improve muscle parameters and potentially reduce the risk of fractures. The aim of this review was to explore 1) the contribution of muscle parameters (i.e., muscle mass, strength, and physical performance) to fracture risk in older adults, and 2) the added predictive accuracy of these parameters beyond the existing fracture assessment tools. These topics provide the rationale for investigating strength and physical performance interventions to reduce fracture risk. Most of the included publications showed that muscle mass is not a good predictor of fracture risk, while poor muscle strength and performance are associated with an increased risk of fracture, particularly in men, independent of age, BMD, and other risk factors for fractures. Muscle strength and performance can potentially improve the predictive accuracy in men beyond that obtained by the fracture risk assessment tools, Garvan FRC and FRAX.

Older people's perceptions and experiences of older people with the Sit-to-stand activity: An ethnographic pre-feasibility study

OBJECTIVE

the purpose of this pre-feasibility study was to examine perceptions and experiences of a Sit-to-stand activity with urban Brazilian community-dwelling older people in their homes.

METHOD

the exploration method was focused ethnography. Purposive sampling was used to recruit 20 older people. Five means of data generation were used, namely: socio-demographic surveys, participant observations, informal interviews, formal semi-structured interviews, and field notes. Data analysis was qualitative content analysis.

RESULTS

the experience of mobility-challenged older people with the Sit-to-stand activity was dependent on their mobility expectations involving many factors that worked together to influence their beliefs and attitudes towards the activity, preferences, behaviors, and cultural perceptions. The participants of this study seemed to find the activity enjoyable; however, the most noticeable shortcomings for their engagement in the Sit-to-stand activity emerged as gaps in their personal and intrapersonal needs.

CONCLUSION

the recommendations generated from the study findings call for the design of implementation strategies for the Sit-to-stand intervention that are tailored to this particular population's needs.

Bidirectional associations of accelerometer-assessed physical activity and sedentary time with physical function among older English adults: the EPIC-Norfolk cohort study

To develop healthy ageing interventions, longitudinal associations between objectively assessed physical behaviours and physical function need to be better understood. We assessed associations between accelerometer-assessed total physical activity (PA), moderate-to-vigorous physical activity (MVPA), light physical activity (LPA), sedentary time and prolonged sedentary bout time, and clinically assessed physical function (grip strength, usual walking speed (UWS), chair stand speed) at two time-points in 3188 participants (≥ 60 years) of the EPIC-Norfolk study. Bidirectional associations were assessed using multivariable linear regression. Over an average of 6.1 years, baseline physical behaviours (greater total PA, MVPA and LPA, and less sedentary time) were associated with better subsequent walking and chair stand speed. Better baseline physical function was associated with better follow-up physical behaviours. There were no bidirectional associations between changes in physical behaviours and grip strength. Improvements in UWS were associated with improvements in all physical behaviours. Improvements in chair stand speed were associated with improvements in total PA, MVPA, and sedentary bout time. Improvements in physical behaviours were associated with improvements in UWS (3.1 cm/s/yr per 100 cpm/yr  total PA, 3.6 cm/s/yr per hr/day/yr MVPA, 2.5 cm/s/yr per hr/day/yr LPA, - 2.9 cm/s/yr per hour/day/yr sedentary time, and - 1.6 cm/s/yr per hr/day/yr prolonged sedentary bout time). Only improvements in total PA, MVPA and sedentary bout time were associated with improvements in chair stand speed. In conclusion, we found bidirectional associations between changes in some physical behaviours and physical function and between baseline physical behaviours and subsequent physical function, highlighting the importance of considering the full range of physical behaviours to promote healthy ageing.

Deep learning predicts all-cause mortality from longitudinal total-body DXA imaging

Background

Mortality research has identified biomarkers predictive of all-cause mortality risk. Most of these markers, such as body mass index, are predictive cross-sectionally, while for others the longitudinal change has been shown to be predictive, for instance greater-than-average muscle and weight loss in older adults. And while sometimes markers are derived from imaging modalities such as DXA, full scans are rarely used. This study builds on that knowledge and tests two hypotheses to improve all-cause mortality prediction. The first hypothesis is that features derived from raw total-body DXA imaging using deep learning are predictive of all-cause mortality with and without clinical risk factors, meanwhile, the second hypothesis states that sequential total-body DXA scans and recurrent neural network models outperform comparable models using only one observation with and without clinical risk factors.

Methods

Multiple deep neural network architectures were designed to test theses hypotheses. The models were trained and evaluated on data from the 16-year-long Health, Aging, and Body Composition Study including over 15,000 scans from over 3000 older, multi-race male and female adults. This study further used explainable AI techniques to interpret the predictions and evaluate the contribution of different inputs.

Results

The results demonstrate that longitudinal total-body DXA scans are predictive of all-cause mortality and improve performance of traditional mortality prediction models. On a held-out test set, the strongest model achieves an area under the receiver operator characteristic curve of 0.79.

Conclusion

This study demonstrates the efficacy of deep learning for the analysis of DXA medical imaging in a cross-sectional and longitudinal setting. By analyzing the trained deep learning models, this work also sheds light on what constitutes healthy aging in a diverse cohort.

Muscle Strength and Physical Performance Are Associated With Risk of Postfracture Mortality But Not Subsequent Fracture in Men

Muscle strength and physical performance are associated with incident fractures and mortality. However, their role in the risk of subsequent fracture and postfracture mortality is not clear. We assessed the association between muscle strength (grip strength) and performance (gait speed and chair stands time) and the risk of subsequent fracture and mortality in 830 men with low-trauma index fracture, who participated in the Osteoporotic Fractures in Men (MrOS) USA Study and had their index measurements assessed within 5 years prior to the index fracture. The annual decline in muscle strength and performance following index fracture, estimated using linear mixed-effects regression, was also examined in relation to mortality. The associations were assessed using Cox proportional hazards models adjusted for age, femoral neck bone mineral density (FN BMD), prior fractures, falls, body mass index (BMI), index fracture site, lifestyle factors, and comorbidities. Over a median follow-up of 3.7 (interquartile range [IQR], 1.3-8.1) years from index fracture to subsequent fracture, 201 (24%) men had a subsequent fracture and over 5.1 (IQR, 1.8-9.6) years to death, and 536 (65%) men died. Index measurements were not associated with subsequent fracture (hazard ratios [HRs] ranging from 0.97 to 1.07). However, they were associated with postfracture mortality. HR (95% confidence interval [CI]) per 1 standard deviation (1-SD) decrement in grip strength: HR 1.12 (95% CI, 1.01-1.25) and gait speed: HR 1.14 (95% CI, 1.02-1.27), and 1-SD increment in chair stands time: HR 1.08 (95% CI, 0.97-1.21). Greater annual declines in these measurements were associated with higher mortality risk, independent of the index values and other covariates. HR (95% CI) per 1-SD annual decrement in change in grip strength: HR 1.15 (95% CI, 1.01-1.33) and in gait speed: HR 1.38 (95% CI, 1.13-1.68), and 1-SD annual increment in chair stands time: HR 1.28 (95% CI, 1.07-1.54). Men who were unable to complete one or multiple tests had greater risk of postfracture mortality (24%-109%) compared to those performed all tests. It remains to be seen whether improvement in these modifiable factors can reduce postfracture mortality. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Endothelin-1-mediated miR-let-7g-5p triggers interlukin-6 and TNF-α to cause myopathy and chronic adipose inflammation in elderly patients with diabetes mellitus

Background: Diabetes and sarcopenia are verified as mutual relationships, which seriously affect the quality of life of the elderly. Endothelin-1 is well investigated, is elevated in patients with diabetes, and is related to muscle cellular senescence and fibrosis. However, the mechanism of ET-1 between diabetes and myopathy is still unclear. The aim of this study was to evaluate the prevalence of sarcopenia in the elderly with diabetes and to clarify its relationship with ET-1 molecular biological mechanism, progress as well as changes in muscle and fat.

Methods: We recruited 157 type 2 diabetes patients over 55 years old and investigated the prevalence of sarcopenia in diabetes patients and examined the association of ET-1 alterations with HbA1c, creatinine, or AMS/ht2. Next, sought to determine how ET-1 regulates inflammation in muscle cells by western blot and qPCR assay. Using XF Seahorse Technology, we directly quantified mitochondrial bioenergetics in 3T3-L1 cells.

Results: ET-1 was positively correlated with HbA1c, creatinine levels, and duration of disease, and negatively correlated with AMS/ht2. We found that ET-1 dose-dependently induces tumor necrosis factor-α (TNF-α) and interleukin (IL)-6β expression through the PI3K/AKT, and NF-κB signaling pathways in C2C12 cells. Also identified that TNF-α, IL-6β, and visfatin releases were found in co-cultured with conditioned medium of ET-1/C2C12 in 3T3-L1 cells. ET-1 also reduces the energy metabolism of fat and induces micro-environment inflammation which causes myopathy. ET-1 also suppresses miR-let-7g-5p expression in myocytes and adipocytes.

Conclusion: We describe a new mechanism of ET-1 triggering chronic inflammation in patients with hyperglycemia.

Effects of Vitamin D3 Supplementation and Resistance Training on 25-Hydroxyvitamin D Status and Functional Performance of Older Adults: A Randomized Placebo-Controlled Trial

Vitamin D status is associated with muscle strength and performance in older adults. To examine the additive effects of vitamin D3 supplementation during resistance training, 100 seniors (65–85 years) participated in a 16-week intervention. Besides a daily dose of 400 mg of calcium, participants received either 800 IU vitamin D3 per day (VDD), 50,000 IU vitamin D3 per month (VDM) or nothing (CON). After the initial loading phase of four weeks, all groups started a 10-week resistance training program. Assessments of 25-hydroxyvitamin D (25(OH)D) status, muscle strength endurance (30-s chair stand and arm curl tests), aerobic capacity (6-min walk test) and functional mobility (gait speed and timed up and go test) were undertaken at baseline, after four weeks and at the end of the study. 25(OH)D status significantly improved in VDD and VDM, but not in CON (time x group: p = 0.021), as 15.2% of CON, 40.0% of VDD and 61.1% of VDM reached vitamin D sufficiency (>30 ng/mL; p = 0.004). Chair stand test, arm curl test, 6-min walk test, gait speed and timed up and go test improved over the whole intervention period (p < 0.05), however only chair stand and arm curl test were selectively affected by resistance training (p < 0.001). Neither muscle strength endurance, nor functional mobility or aerobic capacity were modulated by vitamin D supplementation. Therefore, the mere amelioration of 25(OH)D status of older adults does not lead to an additive effect on muscular performance during RT.

Predictive factors of functional mobility in older women after 12 weeks of resistance training

To analyze the association between functional mobility and anthropometric and functional characteristics of older women after 12 weeks of resistance training. METHODS: Forty-seven community-dwelling older women underwent 12 weeks of supervised resistance training twice a week. The dependent variable (mobility measured by the Timed Up and Go test) and the independent variables (age, body mass index, fat-free mass of the lower limbs, waist circumference, peak knee torque at 60º/s, peak knee torque at 180º/s, functional reach test, and 30-second chair stand test) were measured before and after the intervention. RESULTS: A multivariate analysis showed that age, body mass index, waist circumference, and the 30-second stand test predicted 30% (R2 = 0.30; p = 0.001; F = 5.53) of the total variance regarding an improvement in mobility after resistance training (p < 0.0001; [95% CI 0.72–1.20]; the effect size was considered large [0.90]) when comparing women before and after the intervention. CONCLUSIONS: Age, body mass index, waist circumference, and the 30-second stand test predicted 30% of the increase in functional mobility.