Models of accelerated sarcopenia: critical pieces for solving the puzzle of age-related muscle atrophy

To Synthesize Hydroxyapatite by Modified Low Temperature Method Loaded with Bletilla striata Polysaccharide as Antioxidant for the Prevention of Sarcopenia by Intramuscular Administration

Oxidative stress has been suggested as an important factor in the progress of sarcopenia. The current treatments for sarcopenia have the disadvantages of insufficient effect or daily administration. Therefore, an alternative for effective, safety and long-term treatment may be a solution for unmet needs. Bletilla striata polysaccharide has been reported to have anti-oxidative and anti-inflammatory properties. In this study, we used Bletilla striata polysaccharide (BSP) combined with hydroxyapatite, a carrier. We hypothesized that the resulting combination (BSP-HAP) is a good formula for the controlled release of BSP via intramuscular (IM) administration, so as to prevent the worsening of presarcopenia or even recover from the early stage of the illness. In this research, BSP-HAP was synthesized by a modified low temperature co-precipitation process that would be beneficial for BSP loading. By conducting DCFDA, WST-1 and the Live/Dead assay, BSP-HAP is shown to be a biocompatible material which may release BSP by cells through the endocytosis pathway. Animal studies revealed that the rats treated with BSP-HAP could effectively recover muscle endurance, grip strength or fat/lean mass ratio from lipopolysaccharide (LPS)-induced sarcopenia. This study shows BSP delivered by BSP-HAP system has potential for application in the treatment and prevention of sarcopenia in the future.

Circulating Mediators of Apoptosis and Inflammation in Aging; Physical Exercise Intervention

Sarcopenia is an age-related loss of skeletal muscle mass caused by many cellular mechanisms and also by lifestyle factors such as low daily physical activity. In addition, it has been shown that sarcopenia may be associated with inflammation and cognitive impairment in old age. Regular exercise is key in reducing inflammation and preventing sarcopenia and diseases related to cognitive impairment. The study was designed to assess the impact of exercise training on circulating apoptotic and inflammatory markers of sarcopenia in older adults. Eighty older adults aged 70.5 ± 5.8 years were randomized to the physically active group who participated in a 10-month Tai-Chi training session (TC, n = 40) and the control group who participated in health education sessions (HE, n = 40). Tai-Chi training caused a significant decrease in fat mass (FM) by 3.02 ± 3.99%, but an increase in appendicular skeletal muscle mass index (ASMI) by 1.76 ± 3.17% and gait speed by 9.07 ± 11.45%. Tai-Chi training elevated the plasma levels of C-reactive protein (CRP), tumor necrosis factor (TNFα), and tumor necrosis receptor factor II (TNFRII), and decreased caspases 8 and 9. Despite the increase in TNFα, apoptosis was not initiated, i.e., the cell-free DNA level did not change in the TC group. The study demonstrated that Tai-Chi training significantly reduced the symptoms of sarcopenia through the changes in body composition and physical performance, and improvements in cytokine-related mechanisms of apoptosis.

Excess Glucose Impedes the Proliferation of Skeletal Muscle Satellite Cells Under Adherent Culture Conditions

Glucose is a major energy source consumed by proliferating mammalian cells. Therefore, in general, proliferating cells have the preference of high glucose contents in extracellular environment. Here, we showed that high glucose concentrations impede the proliferation of satellite cells, which are muscle-specific stem cells, under adherent culture conditions. We found that the proliferation activity of satellite cells was higher in glucose-free DMEM growth medium (low-glucose medium with a glucose concentration of 2 mM) than in standard glucose DMEM (high-glucose medium with a glucose concentration of 19 mM). Satellite cells cultured in the high-glucose medium showed a decreased population of reserve cells, identified by staining for Pax7 expression, suggesting that glucose concentration affects cell fate determination. In conclusion, glucose is a factor that decides the cell fate of skeletal muscle-specific stem cells. Due to this unique feature of satellite cells, hyperglycemia may negatively affect the regenerative capability of skeletal muscle myofibers and thus facilitate sarcopenia.

Sarcopenia and Cardiac Dysfunction

Although muscle loss is part of the natural course of human aging, sarcopenia has been associated with an increased risk of physical disability and mortality in older patients. Many heart failure patients concomitantly develop deficits in muscle mass and strength, resulting in decreased quality of life and exercise capacity. An underlying state of inflammation is central to the development of sarcopenia and muscle wasting in heart failure; however, additional research in human models is needed to further delineate the pathophysiology of muscle wasting in these patients. Previous studies have shed light on many of the potential targets for therapeutic intervention of sarcopenia in heart failure; however, physical exercise remains the prominent beneficial intervention. Future research must explore other therapeutic interventions in randomized, double-blind clinical trials, which may help to supplement exercise regimens. Sarcopenia shows promise as an easily measured predictor of outcomes after transcatheter aortic valve replacement.

Sarcopenia as a Prognostic Factor in Peripheral Arterial Disease: Descriptive Review

BACKGROUND

Determine the influence of sarcopenia on the prognosis of peripheral arterial disease (PAD).

METHODS

A systematic search of the PubMed and Cochrane Library databases was performed with the keywords and medical subject heading (MesH): "muscle, skeletal", "sarcopenia", "prognosis", "duration of stay", "death", "mortality", "patient readmission", "length of stay", "peripheral arterial disease", "intermittent claudication" and "critical limb ischemia". Papers published from January 2010 to October 2020 in English, French, Spanish and Portuguese were eligible for inclusion. The primary outcome was overall survival. Secondary outcomes included post-operative complications, amputation, length of hospital stay and hospital readmission.

RESULTS

Of 1071 papers, 8 articles and 1511 patients were included (68.96% male, mean age 71.83 years). Five papers found an inverse relationship between SM area and mortality. Matsubara (2015) found that the 5-year overall survival rates were lower for patients with sarcopenia (23.5% ± 0.18% vs 77.5% ± 0.09% P = 0.001). Matsubara (2016) registered 3-year cardiovascular event-free survival rates of 43.1% and 91.2% for patients with and without sarcopenia (P < 0.01). Juszczak (2018) found that survival was lower in patients with reduced total psoas area. Taniguchi (2019) found that 3-year overall survival rate was 60% for patients with sarcopenia and 87% for patients without sarcopenia (P < 0.05). Shimazoe (2019) concluded sarcopenia was a significant predictor of overall survival. Distinctly, Nyers (2017) concluded that higher ratio bilateral psoas area to L4 vertebral body was associated with an increased risk of death. Two other studies analyzed other characteristics of the SM (density and strength). McDermott (2012) and found that lower calf muscle density and strength were associated with an increase in mortality. Sugai (2019) concluded that patients with major cardiovascular and limb events had a lower SM density.

CONCLUSIONS

Lower SM area and mass seem to be associated with a higher mortality in PAD patients.

Pathophysiological mechanisms explaining poor clinical outcome of older cancer patients with low skeletal muscle mass

Low skeletal muscle mass is highly prevalent in older cancer patients and affects 5% to 89% depending on the type and stage of cancer. Low skeletal muscle mass is associated with poor clinical outcomes such as post-operative complications, chemotherapy toxicity and mortality in older cancer patients. Little is known about the mediating pathophysiological mechanisms. In this review, we summarize proposed pathophysiological mechanisms underlying the association between low skeletal muscle mass and poor clinical outcomes in older cancer patients including a) systemic inflammation; b) insulin-dependent glucose handling; c) mitochondrial function; d) protein status and; e) pharmacokinetics of anticancer drugs. The mechanisms of altered myokine balance negatively affecting the innate and adaptive immune system, and altered pharmacokinetics of anticancer drugs leading to a relative overdosage of anticancer drugs are best-substantiated. The effects of glucose intolerance and circulating mitochondrial DNA as a consequence of low skeletal muscle mass are topics of interest for future research. Restoring myokine balance through physical exercise, exercise mimetics, neuro-muscular activation and adapting anticancer drug dosing on skeletal muscle mass could be targeted approaches to improve clinical outcomes in older cancer patients with low skeletal muscle mass.

Sarcopenia and Menopause: The Role of Estradiol

During aging and menopausal transition in women, a progressive muscle degeneration (i.e. decrease in quality and muscle function) occurs. This muscle dysfunction, caused by decreased proliferation of muscle satellite cells, increased levels of inflammatory markers, and altered levels of sex hormones, exposes women to a raised incidence of sarcopenia. In this regard, hormonal balance and, in particular, estradiol, seems to be essential in skeletal muscle function. The role of the estradiol on satellite cells and the release of inflammatory cytokines in menopausal women are reviewed. In particular, estradiol has a beneficial effect on the skeletal muscle by stimulating satellite cell proliferation. Skeletal muscle can respond to estrogenic hormonal control due to the presence of specific receptors for estradiol at the level of muscle fibers. Additionally, estradiol can limit inflammatory stress damage on skeletal muscle. In this review, we primarily focused on the role of estradiol in sarcopenia and on the possibility of using Estradiol Replacement Therapy, which combined with nutritional and physical activity programs, can counteract this condition representing a valid tool to treat sarcopenia in women.

The Association Between Diabetes Mellitus and Risk of Sarcopenia: Accumulated Evidences From Observational Studies

AIM

We performed a meta-analysis of observational studies to evaluate the association between the presence of sarcopenia and HbA1c, prediabetes, diabetes and diabetic complications.

METHOD

The PubMed, Embase, Cochrane and Web of Science databases were searched from inception to May 2021. We included full-text English language articles that reported the prevalence of sarcopenia in patients with and without diabetes. Quality assessment was performed according to the Newcastle- Ottawa scale for observational studies.

RESULTS

Sixteen studies were included in the meta-analysis. Three studies showed that high HbA1c levels lead to loss of muscle mass, and one study involving prediabetes showed that people with prediabetes had lower muscle mass, strength, and performance than non-diabetic population. Seven studies showed that people with diabetes had a higher risk of sarcopenia than those without diabetes (combined OR: 2.09, 95% CI:1.62-2.70). The remaining five studies suggested that diabetic complications increased the risk of sarcopenia (combined OR: 2.09,95% CI:1.62-2.70).

CONCLUSION

High HbA1c levels, prediabetes, diabetes and diabetes complications were associated with an increased risk of sarcopenia. Therapeutic strategies addressed to avoid the conversion of IGT to diabetes and to optimize glycemic control are warranted to prevent or arrest sarcopenia in the diabetic population.

The impact of disease-related immobilization on thigh muscle mass and strength in older hospitalized patients

Background

We assessed the quantitative changes in muscle mass and strength during 2 weeks of hospitalization in immobile and mobile acutely ill hospitalized older adults.

Methods

Forty-one patients (82.4 ± 6.6 years, 73.0% females) participated in this prospective longitudinal observational study. Mobility status was defined according to walking ability as described in the Barthel-Index. Functional status, including handgrip strength and isometric knee-extension strength, and mid-thigh magnetic resonance imaging (MRI) measurements of cross-sectional area (CSA) were conducted on admission and at discharge.

Results

Twenty-two participants (54%) were immobile and 19 (46%) mobile. In all, 54.0 and 12.0% were at risk of malnutrition and malnourished, respectively. The median time between baseline and follow-up for MRI scans were 13 days in mobile and immobile participants (P = 0.072). Mid-thigh muscle and subcutaneous fat CSA significantly decreased by 3.9cm² (5.0%, P = 0.002) and 5.3cm² (5.7%, P = 0.036) during hospitalization whereas intermuscular fat remained unchanged in immobile subjects. No significant changes were observed in mobile patients. In a regression analysis, mobility was the major independent risk factor for changes in mid-thigh muscle CSA as a percentage of initial muscle area (P = 0.022) whereas other variables such as age (P = 0.584), BMI (P = 0.879), nutritional status (P = 0.835) and inflammation (P = 0.291) were not associated with muscle mass changes. There was a significant decrease in isometric knee extension strength (P = 0.002) and no change in handgrip strength (P = 0.167) in immobile patients whereas both parameters increased significantly over time in mobile patients (P = 0.048 and P = 0.012, respectively).

Conclusions

Two weeks of disease-related immobilization result in a significant loss of thigh muscle mass and muscle strength in older patients with impaired mobility. Concomitantly, there was a significant reduction of subcutaneous adipose tissue in immobile older hospitalized patients whereas no changes were observed in intermuscular fat among these patients. These data highlight the importance of mobility support in maintaining muscle mass and function in older hospitalized patients.

Associations between dietary patterns and physical fitness among Chinese elderly

OBJECTIVE

To explore the relationship between dietary patterns and physical fitness among older Chinese (≥60 years) individuals.

DESIGN

Cross-sectional survey. Dietary data were collected by a simplified semi-quantitative FFQ. The 30-s Chair Stand test (30sCST), 30-s Arm Curl test (30sACT), 8-foot Time Up-and-Go test (8fTUAGT) and 6-min Walking test (6mWT) were used to assess physical fitness. Dietary patterns were obtained by factor analysis. The association between dietary patterns and physical fitness was explored by multiple logistic regression.

SETTING

Six communities (villages) of three districts in Liaocheng City (Shandong Province, China).

PARTICIPANTS

A total of 596 residents were recruited from April to May 2017.

RESULTS

Among 556 residents who were finally enrolled, 196 were men (35 %) and 360 were women (65 %). Three dietary patterns were identified: 'Western', 'Vegetarian' and 'Modern'. The 30sACT revealed that men in the fourth quartile of the Western pattern were less likely to be classified in the 'high-level' group, but men in the fourth quartile of the Vegetarian pattern were classified in the high-level group. The 6mWT revealed that men in the fourth quartile of the Modern pattern were classified in the high-level group. These associations were independent of confounding factors.

CONCLUSIONS

Adherence to the Vegetarian pattern and Modern pattern may be protective factors for maintaining good physical fitness in older Chinese individuals. The Western pattern may lead to poor physical fitness in this population.

Association of Body Shape Index (ABSI) with Hand Grip Strength

Hand grip is a leading measure of muscle strength and general health, yet its association with body shape is not well characterized. Here, we examine correlations between grip strength, a body shape index (ABSI), and body mass index (BMI) in the 2011-2014 United States National Health and Nutrition Examination Survey cohorts. Grip strength was found to correlate negatively with ABSI (though positively with BMI), suggesting that those with a more central body profile tend to be weaker than others with the same weight. Individuals with low grip strength, as well as those with high ABSI, were more likely to die during follow up, whereas there was no association of BMI with mortality hazard. Transforming the grip strength, ABSI, and BMI by taking their logarithm prior to standardization did not meaningfully change the associations seen. These findings suggest that combining anthropometrics (ABSI, BMI) with grip strength may better identify individual mortality hazard in research studies and clinical practice.

Unraveling the Links Underlying Arterial Stiffness, Bone Demineralization, and Muscle Loss

The effects of elevated arterial stiffness on cardiovascular outcomes are widely studied, whereas the relation to noncardiovascular outcomes relevant to older persons, such as the effect on bones and muscles, is less well established. Arterial stiffness, bone demineralization, and muscle loss are all age-related processes with common risk factors, however, whether these are just parallel age-related alterations or whether these processes share common pathways is not yet understood. In this review, we outline previous literature using different assessments of arterial stiffness in various populations across the world to produce a comprehensive overview. Although there are many studies showing an association between arterial stiffness and loss of bone and muscle, the majority are cross-sectional and there is limited longitudinal evidence to justify causal conclusions. We also give an in-depth review of hypotheses and possible mechanisms which may underlie these associations including hormone dysregulation, impaired glucose metabolism, and inflammation. This narrative review highlights the associations between vessels, bones, and muscles with aging, offering insights into possible shared pathways.

Docosahexaenoic Acid, a Potential Treatment for Sarcopenia, Modulates the Ubiquitin-Proteasome and the Autophagy-Lysosome Systems

One of the characteristic features of aging is the progressive loss of muscle mass, a nosological syndrome called sarcopenia. It is also a pathologic risk factor for many clinically adverse outcomes in older adults. Therefore, delaying the loss of muscle mass, through either boosting muscle protein synthesis or slowing down muscle protein degradation using nutritional supplements could be a compelling strategy to address the needs of the world’s aging population. Here, we review the recently identified properties of docosahexaenoic acid (DHA). It was shown to delay muscle wasting by stimulating intermediate oxidative stress and inhibiting proteasomal degradation of muscle proteins. Both the ubiquitin–proteasome and the autophagy–lysosome systems are modulated by DHA. Collectively, growing evidence indicates that DHA is a potent pharmacological agent that could improve muscle homeostasis. Better understanding of cellular proteolytic systems associated with sarcopenia will allow us to identify novel therapeutic interventions, such as omega-3 polyunsaturated fatty acids, to treat this disease.

Optimizing Skeletal Muscle Anabolic Response to Resistance Training in Aging

Loss of muscle mass and strength with aging, also termed sarcopenia, results in a loss of mobility and independence. Exercise, particularly resistance training, has proven to be beneficial in counteracting the aging-associated loss of skeletal muscle mass and function. However, the anabolic response to exercise in old age is not as robust, with blunted improvements in muscle size, strength, and function in comparison to younger individuals. This review provides an overview of several physiological changes which may contribute to age-related loss of muscle mass and decreased anabolism in response to resistance training in the elderly. Additionally, the following supplemental therapies with potential to synergize with resistance training to increase muscle mass are discussed: nutrition, creatine, anti-inflammatory drugs, testosterone, and growth hormone (GH). Although these interventions hold some promise, further research is necessary to optimize the response to exercise in elderly patients.

Muscle mass gain is positively associated with functional recovery in patients with sarcopenia after stroke

OBJECTIVE

Intervention for treating sarcopenia is of great concern in clinical settings. The aim of this study was to investigate the relationship between changes in skeletal muscle mass and functional outcomes in patients with sarcopenia after stroke.

METHODS

A retrospective cohort study of stroke patients with sarcopenia consecutively admitted to a single center's convalescent rehabilitation wards was conducted from 2015 to 2018. Sarcopenia was defined as a loss of skeletal muscle mass index (SMI) with bioelectrical impedance and decreased muscle strength as measured by handgrip strength; cut-off values were adopted from the 2019 Asian Working Group for Sarcopenia. Changes in SMI during hospitalization were measured. Outcomes included the motor domain of Functional Independence Measure at discharge and its gain. Multivariate analysis determined whether the changes in SMI were associated with these outcomes.

RESULTS

During the study period, 272 stroke patients were enrolled. Of those, 120 patients (44%) (mean age 79 years, 70 females) were diagnosed with sarcopenia. The mean (SD) for changes in SMI was 0.2 (0.5) kg/m². Multiple linear regression analysis showed that changes in SMI were significantly associated with Functional Independence Measure - motor at discharge (β=0.175, P=0.003) and Functional Independence Measure - motor gain (β=0.247, P=0.003).

CONCLUSIONS

Muscle mass gain may be positively associated with functional recovery in patients with sarcopenia after stroke. Exercise and nutritional therapy to increase skeletal muscle mass, in addition to conventional stroke rehabilitation, is needed for these patients.

Physical Activity Scale for the Elderly (PASE) Score Is Related to Sarcopenia in Noninstitutionalized Older Adults

BACKGROUND AND PURPOSE

Sarcopenia, a loss of muscle mass and strength accompanying aging, is common in older adults who are not physically active. Nevertheless, the association between physical activity and sarcopenia has not been extensively studied. Therefore, we examined the relationship of both muscle mass and muscle strength with physical activity as quantified using the Physical Activity Scale for Elderly (PASE).

METHODS

PASE score, muscle mass by bioimpendiometry, and muscle strength by handgrip were evaluated in a cohort study of 420 older adult participants (mean age 82.4 [5.9] years), admitted to the Comprehensive Geriatric Assessment Center. Sarcopenia was assessed as indicated in the European Working Group on Sarcopenia in Older People (EWGSOP) consensus.

RESULTS

PASE score was lower in sarcopenic (40.2 [89.0]) than in non-sarcopenic (92.0 [52.4]) older adults (P < .001). Curvilinear regression analysis demonstrated that PASE score is related with muscle mass (R = 0.63; P < .001) and strength (R = 0.51; P < .001).

CONCLUSIONS

The present study indicates that PASE score is curvilinearly related to muscle mass and strength and that low PASE score identifies sarcopenic noninstitutionalized older adults. This evidence suggests that PASE score evaluated together with muscle mass and strength may identify older adults at high risk of sarcopenia.

Determinants of Adherence in Time-Restricted Feeding in Older Adults: Lessons from a Pilot Study

Time-restricted feeding (TRF) is a type of intermittent fasting in which no calories are commonly consumed for approximately 12-18 hours on a daily basis. The health benefits of this eating pattern have been shown in overweight adults, with improvements in cardiometabolic risk factors as well as the preservation of lean mass during weight loss. Although TRF has been well studied in younger and middle-aged adults, few studies have evaluated the effects of TRF in older adults. Thus, the goal of this study was to evaluate older-adult perspectives regarding the real-world advantages, disadvantages, and challenges to adopting a TRF eating pattern among participants aged 65 and over. A four-week single-arm pre- and post-test design was used for this clinical pilot trial TRF intervention study. Participants were instructed to fast for approximately 16 h per day with the daily target range between 14 and 18 h. Participants were provided with the TRF protocol at a baseline visit, along with a pictorial guide that depicted food items and beverages that were allowed and not allowed during fasting windows to reinforce that calorie-containing items were to be avoided. The trial interventionist called each participant weekly to promote adherence, review the protocol, monitor for adverse events, and provide support and guidance for any challenges faced during the intervention. Participants were instructed to complete daily eating time logs by recording the times at which they first consumed calories and when they stopped consuming calories. At the end of the intervention, participants completed an exit interview and a study-specific Diet Satisfaction Survey (Table 1) to assess their satisfaction, feasibility, and overall experience with the study intervention. Of the 10 participants who commenced the study (mean age = 77.1 y; 6 women, 4 men), nine completed the entire protocol. Seven of the ten participants reported easy adjustment to a 16-hour fast and rated the difference from normal eating patterns as minimal. Eight participants reported no decrease in energy during fasting periods, with greater self-reported activity levels in yardwork and light exercise. Adverse events were rare, and included transient headaches, which dissipated with increased water intake, and dizziness in one participant, which subsided with a small snack. The findings of the current trial suggest that TRF is an eating approach that is well tolerated by most older adults. Six participants, however, did not fully understand the requirements of the fasting regimen, despite being provided with specific instructions and a pictorial guide at a baseline visit. This suggests that more instruction and/or participant contact is needed in the early stages of a TRF intervention to promote adherence.

Factors associated with 36-month loss to follow-up and mortality outcomes among HIV-infected adults on antiretroviral therapy in Central Kenya

BACKGROUND

The scale-up of HIV treatment programs has resulted in a reduction in HIV-related morbidity and mortality. However, retention of patients in these programs remains a challenge in sub-Saharan Africa. Understanding factors associated with loss to follow-up (LTFU) and mortality outcomes is therefore important to inform targeted program interventions.

METHODS

A retrospective multi-cohort analysis of 23,890 adult patients on ART over 36 months of follow-up in Kenya was done. Multivariate logistic regression analysis was done to assess for factors associated with LTFU and mortality at 6, 12, 24, and 36 months of follow-up.

RESULTS

Majority, 67.7%, were female. At 36 months, 27.2% were LTFU and 13.5% had died. Factors associated with mortality at 36 months included older age (51 years and above) using 20-35 years as reference [(adjusted odds ratio [aOR], 1.51, 95% confidence interval (CI) 1.23-1.86, p < 0.001], being male (aOR, 1.59, 95% CI 1.39-1.83, p < 0.001), divorced using married as reference (aOR, 1.86, 95% CI 1.56-2.22, p < 0.001), having a body mass index (BMI) score of less than 18.5 kg/m2 using 18.5-24.9 kg/m2 as reference (aOR = 1.79, 95% CI 1.52-2.11, p < 0.001), and, World Health Organization stage III and IV using stage I as the reference (aOR, 1.94, 95% CI 1.43-2.63 and aOR, 4.24, 95% CI 3.06-5.87, p < 0.001 respectively). Factors associated with LTFU at 36 months included being young between 20 and 35 years (aOR, 1.49, 95% CI 1.40-1.59, p < 0.001) using 36-50 years as reference, being male (aOR, 1.19, 95% CI 1.12-1.27, p < 0.001), and being single or divorced using married as reference (aOR, 1.34, 95% CI 1.23-1.45 and aOR, 1.25, 95% CI 1.15-1.36, p < 0.001 respectively). Patients with baseline BMI of less than 18.5 kg/m2 using normal BMI as reference (aOR, 1.68, 95% CI 1.39-2.02, p < 0.001) were also likely to be LTFU.

CONCLUSIONS

Factors associated with LTFU and mortality were generally similar over time. Implementation of programs in similar settings should be tailored to gender, age profiles, nutritional, and, marital status of patients to address LTFU. In addition, programs should focus on the care of older patients to reduce the risk of mortality.

Perioperative nutritional supplementation and skeletal muscle mass in older hip-fracture patients

Older people with hip fractures are often malnourished at the time of fracture, which can have substantial influence on mortality and clinical outcomes, as well as functional outcome and quality of life. A close relationship between protein intake and muscle maintenance has been demonstrated. Skeletal muscle weakness is an independent risk factor for falls and fall-related injuries in the elderly and is an independent marker of prognosis. However, the effect of perioperative nutritional interventions on outcomes in elderly hip-fracture patients remains controversial. In this narrative review, an overview is presented of the existing literature on nutritional status and sarcopenia in elderly hip-fracture patients, clinical outcomes, and the effects of nutritional intervention on outcome and rehabilitation in this patient group.

Sarcopenia in relation to nutrition and lifestyle factors among middle-aged and older Korean adults with obesity

PURPOSE

To examine the prevalence of sarcopenic obesity (SO) and its association with nutrition and lifestyle factors.

METHODS

Data from the 2008-2011 Korea National Health and Nutrition Examination Survey for 3937 Korean individuals aged 40 years or older with obesity defined by the modified Asia-Pacific criteria (BMI ≥ 25 kg/m²) were used. Sarcopenia was defined as an appendicular skeletal muscle mass divided by weight (%) of < 1 SD below the sex-specific mean for young adults. Logistic regression models were used for the associations controlling covariates.

RESULTS

The prevalence of SO was 52.5%. The SO group had insufficient energy intake, protein, and antioxidant micronutrients, a lower overall dietary quality, a lower physical activity, and higher rates of negative psychological factors than the non-sarcopenic obesity group (p < 0.05). After controlling for covariates, having high mean adequacy ratio scores which was calculated by averaging the sum of the nutrient adequacy ratios had a 94% lower prevalence of SO in the older individuals. Low participation in aerobic exercises had a 74% higher prevalence of SO in the older aged group, and high participation in flexibility exercises had a 11% lower prevalence of SO in the middle-aged group. Interestingly, negative psychological factors were found only in the middle-aged adults with SO (p < 0.05).

CONCLUSION

Sarcopenia was present in over half of the middle-aged and older Korean adults with obesity. Having high dietary quality, increased physical activity, and positive psychological health were associated with a low prevalence of SO.

Framework for Considering Productive Aging and Work

OBJECTIVES

The U.S. population is experiencing a demographic transition resulting in an aging workforce. The objective of this article is to elucidate and expand an approach to keep that workforce safe, healthy, and productive.

METHODS

This article elucidates the framework for the National Center for Productive Aging at Work of the National Institute for Occupational Safety and Health. Subject matter experts used a snowball method to review published literature to substantiate elements in the framework.

RESULTS

Evidence-based literature supports a productive aging framework for the workforce involving the following elements: 1) life span perspective; 2) comprehensive and integrated approaches to occupational safety and health; 3) emphasis on positive outcomes for both workers and organizations; and 4) supportive work culture for multigenerational issues.

CONCLUSION

The productive aging framework provides a foundational and comprehensive approach for addressing the aging workforce.

Efficacy of Nutritional Interventions as Stand-Alone or Synergistic Treatments with Exercise for the Management of Sarcopenia

Sarcopenia is an age-related and accelerated process characterized by a progressive loss of muscle mass and strength/function. It is a multifactorial process associated with several adverse outcomes including falls, frailty, functional decline, hospitalization, and mortality. Hence, sarcopenia represents a major public health problem and has become the focus of intense research. Unfortunately, no pharmacological treatments are yet available to prevent or treat this age-related condition. At present, the only strategies for the management of sarcopenia are mainly based on nutritional and physical exercise interventions. The purpose of this review is, thus, to provide an overview on the role of proteins and other key nutrients, alone or in combination with physical exercise, on muscle parameters.

Aging- and obesity-related peri-muscular adipose tissue accelerates muscle atrophy

Sarcopenia due to loss of skeletal muscle mass and strength leads to physical inactivity and decreased quality of life. The number of individuals with sarcopenia is rapidly increasing as the number of older people increases worldwide, making this condition a medical and social problem. Some patients with sarcopenia exhibit accumulation of peri-muscular adipose tissue (PMAT) as ectopic fat deposition surrounding atrophied muscle. However, an association of PMAT with muscle atrophy has not been demonstrated. Here, we show that PMAT is associated with muscle atrophy in aged mice and that atrophy severity increases in parallel with cumulative doses of PMAT. We observed severe muscle atrophy in two different obese model mice harboring significant PMAT relative to respective control non-obese mice. We also report that denervation-induced muscle atrophy was accelerated in non-obese young mice transplanted around skeletal muscle with obese adipose tissue relative to controls transplanted with non-obese adipose tissue. Notably, transplantation of obese adipose tissue into peri-muscular regions increased nuclear translocation of FoxO transcription factors and upregulated expression FoxO targets associated with proteolysis (Atrogin1 and MuRF1) and cellular senescence (p19 and p21) in muscle. Conversely, in obese mice, PMAT removal attenuated denervation-induced muscle atrophy and suppressed upregulation of genes related to proteolysis and cellular senescence in muscle. We conclude that PMAT accumulation accelerates age- and obesity-induced muscle atrophy by increasing proteolysis and cellular senescence in muscle.

ULK2 is essential for degradation of ubiquitinated protein aggregates and homeostasis in skeletal muscle

Basal protein turnover, which largely relies on the degradation of ubiquitinated substrates, is instrumental for maintenance of muscle mass and function. However, the regulation of ubiquitinated protein degradation in healthy, nonatrophying skeletal muscle is still evolving, and potential tissue-specific modulators remain unknown. Using an unbiased expression analysis of 34 putative autophagy genes across mouse tissues, we identified unc-51 like autophagy activating kinase (Ulk)2, a homolog of the yeast autophagy related protein 1, as particularly enriched in skeletal muscle. Subsequent experiments revealed accumulations of insoluble ubiquitinated protein aggregates associated with the adaptors sequestosome 1 (SQSTM1, also known as p62) and next to breast cancer type 1 susceptibility protein gene 1 protein (NBR1) in adult muscles with ULK2 deficiency. ULK2 deficiency also led to impaired muscle force and caused myofiber atrophy and degeneration. These features were not observed in muscles with deficiency of the ULK2 paralog, ULK1. Furthermore, short-term ULK2 deficiency did not impair autophagy initiation, autophagosome to lysosome fusion, or protease activities of the lysosome and proteasome. Altogether, our results indicate that skeletal muscle ULK2 has a unique role in basal selective protein degradation by stimulating the recognition and proteolytic sequestration of insoluble ubiquitinated protein aggregates associated with p62 and NBR1. These findings have potential implications for conditions of poor protein homeostasis in muscles as observed in several myopathies and aging.-Fuqua, J. D., Mere, C. P., Kronemberger, A., Blomme, J., Bae, D., Turner, K. D., Harris, M. P., Scudese, E., Edwards, M., Ebert, S. M., de Sousa, L. G. O., Bodine, S. C., Yang, L., Adams, C. M., Lira, V. A. ULK2 is essential for degradation of ubiquitinated protein aggregates and homeostasis in skeletal muscle.

Large data and Bayesian modeling-aging curves of NBA players

Researchers interested in changes that occur as people age are faced with a number of methodological problems, starting with the immense time scale they are trying to capture, which renders laboratory experiments useless and longitudinal studies rather rare. Fortunately, some people take part in particular activities and pastimes throughout their lives, and often these activities are systematically recorded. In this study, we use the wealth of data collected by the National Basketball Association to describe the aging curves of elite basketball players. We have developed a new approach rooted in the Bayesian tradition in order to understand the factors behind the development and deterioration of a complex motor skill. The new model uses Bayesian structural modeling to extract two latent factors, those of development and aging. The interaction of these factors provides insight into the rates of development and deterioration of skill over the course of a player's life. We show, for example, that elite athletes have different levels of decline in the later stages of their career, which is dependent on their skill acquisition phase. The model goes beyond description of the aging function, in that it can accommodate the aging curves of subgroups (e.g., different positions played in the game), as well as other relevant factors (e.g., the number of minutes on court per game) that might play a role in skill changes. The flexibility and general nature of the new model make it a perfect candidate for use across different domains in lifespan psychology.

ADNP differentially interact with genes/proteins in correlation with aging: a novel marker for muscle aging

Activity-dependent neuroprotective protein (ADNP) is essential for embryonic development with ADNP mutations leading to syndromic autism, coupled with intellectual disabilities and motor developmental delays. Here, mining human muscle gene-expression databases, we have investigated the association of ADNP transcripts with muscle aging. We discovered increased ADNP and its paralogue ADNP2 expression in the vastus lateralis muscle of aged compared to young subjects, as well as altered expression of the ADNP and the ADNP2 genes in bicep brachii muscle of elderly people, in a sex-dependent manner. Prolonged exercise resulted in decreased ADNP expression, and increased ADNP2 expression in an age-dependent manner in the vastus lateralis muscle. ADNP expression level was further correlated with 49 genes showing age-dependent changes in muscle transcript expression. A high degree of correlation with ADNP was discovered for 24 genes with the leading gene/protein being NMNAT1 (nicotinamide nucleotide adenylyl transferase 1). Looking at correlations differentiating the young and the old muscles and comparing protein interactions revealed an association of ADNP with the cell division cycle 5-like protein (CDC5L), and an aging-muscle-related interactive pathway in the vastus lateralis. In the bicep brachii, very high correlation was detected with genes associated with immune functions as well as mitochondrial structure and function among others. Taken together, the results suggest a direct association of ADNP with muscle strength and implicate ADNP fortification in the protection against age-associated muscle wasting.

Insulin-Like Growth Factor-I Protects Against the Detrimental Effects of Advanced Glycation End Products and High Glucose in Myoblastic C2C12 Cells

Previous studies suggested that advanced glycation end products (AGEs) and insulin-like growth factor-I (IGF-I) are involved in the mechanism of diabetes-induced sarcopenia. In this study, we examined effects of treatments with AGEs and/or IGF-I for 24 h on myogenic differentiation and apoptosis in mouse myoblastic C2C12 cells. Real-time PCR and Western blot were performed to investigate mRNA and protein expressions, and apoptosis was examined by using a DNA fragment detection ELISA kit. AGE3 significantly decreased mRNA and protein expressions of MyoD and Myogenin, whereas IGF-I significantly increased them and attenuated the effects of AGE3. AGEs significantly decreased endogenous IGF-I mRNA expression and suppressed IGF-I-induced Akt activation. High glucose (22 mM) significantly increased mRNA expression of Rage, a receptor for AGEs, while IGF-I significantly decreased it. DNA fragment ELISA showed that AGE2 and AGE3 significantly increased apoptosis of C2C12 cells, whereas IGF-I significantly suppressed the AGE2- and AGE3-induced apoptosis. In contrast, high glucose enhanced AGE3-induced apoptosis. IGF-I significantly attenuated the effects of high glucose plus AGE3 on the mRNA and protein expressions of MyoD and Myogenin as well as the apoptosis. These findings indicate that AGEs inhibit myogenic differentiation and increase apoptosis in C2C12 cells, and that high glucose increases RAGE and enhances the AGE3-induced apoptosis, suggesting that AGEs and high glucose might contribute to the reduction of muscle mass and function. Moreover, IGF-I attenuated the detrimental effects of AGEs and high glucose in myoblastic cells; thus, IGF-I-Akt signal could be a therapeutic target of DM-induced sarcopenia.

Lipotoxicity, aging, and muscle contractility: does fiber type matter?

Sarcopenia is a universal characteristic of the aging process and is often accompanied by increases in whole-body adiposity. These changes in body composition have important clinical implications, given that loss of muscle and gain of fat mass are both significantly and independently associated with declining physical performance as well as an increased risk for disability, hospitalizations, and mortality in older individuals. This increased fat mass is not exclusively stored in adipose depots but may become deposited in non-adipose tissues, such as skeletal muscle, when the oxidative capacity of the adipose tissue itself is exceeded. The redistributed adipose tissue is thought to exert detrimental local effects on the muscle environment given the close proximity. Thus, sarcopenia observed with aging may be better defined in the context of loss of muscle quality rather than loss of muscle quantity per se. In this perspective, we briefly review the age-related physiological changes in cellularity, secretory profiles, and inflammatory status of adipose tissue which drive lipotoxicity (spillover) of skeletal muscle and then provide evidence of how this may affect specific fiber type contractility. We focus on biological contributors (cellular machinery) to contractility for which there is some evidence of vulnerability to lipid stress distinguishing between fiber types.

Different Cognitive Frailty Models and Health- and Cognitive-related Outcomes in Older Age: From Epidemiology to Prevention

Frailty, a critical intermediate status of the aging process that is at increased risk for negative health-related events, includes physical, cognitive, and psychosocial domains or phenotypes. Cognitive frailty is a condition recently defined by operationalized criteria describing coexisting physical frailty and mild cognitive impairment (MCI), with two proposed subtypes: potentially reversible cognitive frailty (physical frailty/MCI) and reversible cognitive frailty (physical frailty/pre-MCI subjective cognitive decline). In the present article, we reviewed the framework for the definition, different models, and the current epidemiology of cognitive frailty, also describing neurobiological mechanisms, and exploring the possible prevention of the cognitive frailty progression. Several studies suggested a relevant heterogeneity with prevalence estimates ranging 1.0–22.0% (10.7–22.0% in clinical-based settings and 1.0–4.4% in population-based settings). Cross-sectional and longitudinal population-based studies showed that different cognitive frailty models may be associated with increased risk of functional disability, worsened quality of life, hospitalization, mortality, incidence of dementia, vascular dementia, and neurocognitive disorders. The operationalization of clinical constructs based on cognitive impairment related to physical causes (physical frailty, motor function decline, or other physical factors) appears to be interesting for dementia secondary prevention given the increased risk for progression to dementia of these clinical entities. Multidomain interventions have the potential to be effective in preventing cognitive frailty. In the near future, we need to establish more reliable clinical and research criteria, using different operational definitions for frailty and cognitive impairment, and useful clinical, biological, and imaging markers to implement intervention programs targeted to improve frailty, so preventing also late-life cognitive disorders.

Preoperative low skeletal muscle mass as a risk factor for pharyngocutaneous fistula and decreased overall survival in patients undergoing total laryngectomy

Background

Low skeletal muscle mass (SMM) is associated with postoperative complications, prolonged hospital stay, and short overall survival (OS) in surgical oncology. We aimed to investigate this association in patients undergoing total laryngectomy (TL).

Methods

A retrospective study was performed of patients undergoing TL. SMM was measured using CT or MRI scans at the level of the third cervical vertebra (C3).

Results

In all, 235 patients were included. Low SMM was observed in 109 patients (46.4%). Patients with low SMM had more pharyngocutaneous fistulas (PCFs) than patients with normal SMM (34.9% vs 20.6%; P = .02) and prolonged hospital stay (median, 17 vs 14 days; P < .001). In multivariate analysis, low SMM (hazards ratio, 1.849; 95% confidence interval, 1.202‐2.843) and high N stage were significant prognosticators of decreased OS.

Conclusion

Low SMM is associated with PCF and prolonged hospital stay in patients undergoing TL. Low SMM is an independent prognostic factor for shorter OS.

Effect of Creatine Supplementation Dosing Strategies on Aging Muscle Performance

OBJECTIVE

This study compared the effects of different creatine supplementation dosages, independent of resistance training, on aging muscle performance and functionality.

DESIGN AND PARTICIPANTS

Using a double-blind, repeated measures design, participants were randomized to one of three groups: Creatine-High (CR-H; n=11; 0.3 g/kg/day of creatine + 0.1 g/kg/day of maltodextrin), Creatine-Moderate (CR-M: n=11; 0.1 g/kg/day of creatine + 0.3 g/kg/day of maltodextrin) or Placebo (PLA; n=11; 0.4 g/kg/day of maltodextrin) for 10 consecutive days.

MEASUREMENTS

The primary dependent variables measured at baseline and after supplementation included muscle strength (1-repetition maximum leg press, chest press, hand-grip), muscle endurance (leg press and chest press; maximal number of repetitions performed for 1 set at 80% and 70% baseline 1-repetition maximum respectively), and physical performance (dynamic balance).

RESULTS

There was a significant increase over time for muscle strength (Leg press: CR-H pre 161.5 ± 55.1 kg, post 169.2 ± 59.2 kg; CR-M pre 145.2 ± 47.7 kg, post 151.7 ± 45.0 kg; PLA pre 163.7 ± 51.5 kg, post 178.2 ± 65.6 kg, p = 0.001; Chest press: CR-H pre 57.0 ± 26.2 kg, post 58.8 ± 28.0 kg; CR-M pre 54.5 ± 27.9 kg, post 56.8 ± 30.1 kg; PLA pre 55.1 ± 26.9 kg, post 58.5 ± 30.1 kg, p = 0.001) and endurance (Leg press: CR-H pre 17.1 ± 6.0 reps, post 21.0 ± 7.2 reps; CR-M pre 24.1 ± 11.6 reps, post 29.1 ± 17.0 reps; PLA pre 23.8 ± 9.7 reps, post 29.5 ± 11.9 reps, p = 0. 001; Chest press: CR-H pre 15.6 ± 2.7 reps, post 18.9 ± 2.7 reps; CR-M pre 18.0 ± 5.0 reps, post 19.9 ± 7.1 reps; PLA pre 20.5 ± 6.2 reps, post 21.6 ± 5.5 reps, p = 0. 001), with no other differences.

CONCLUSION

Short-term creatine supplementation, independent of dosage and resistance training, has no effect on aging muscle performance.

Evaluation of Oxidative Stress Parameters and Antioxidant Status in Plasma and Erythrocytes of Elderly Diabetic Patients with Sarcopenia

OBJECTIVES

Oxidative stress may play a role in the pathogenesis of both sarcopenia and diabetes. Although the risk of sarcopenia is increased in people with type 2 diabetes, the relationship between sarcopenia oxidative stress and antioxidant status among the older diabetes population is not well studied. The aim of this present study was to evaluate the relationship between oxidative stress and antioxidant status and sarcopenia in elderly diabetic patients.

DESIGN

This was a cross-sectional designed study with a control group. A total of 60 type 2 diabetic elderly patients were enrolled in the study (30 sarcopenic and 30 controls).

MEASUREMENTS

Comprehensive geriatric assessments and anthropometric measurements were performed. Sarcopenia was diagnosed according to the European Working Group on Sarcopenia in Older People. Skeletal muscle mass was measured using bioelectrical impedance analysis. A handheld dynamometer was used for skeletal muscle strength measurements. Gait speed was measured using a 4 meter walking test. Plasma malondialdehyde (MDA), glutathione peroxidase (GSH-Px) and erythrocyte MDA, GSH-Px, superoxide dismutase (SOD), catalase and xanthine oxidase (XO) measurements were performed.

RESULTS

While plasma XO was significantly higher in sarcopenic individuals (0.406(0.225-0.775)) compared to controls (0.312(0.112-0.712)) (p=0.006), plasma GSH-Px was significantly lower in sarcopenic individuals (0.154(0.101-0.274)) compared to controls (0.204(0.12-.0312)) (p=0.003). Plasma XO (OR: 2.69 (CI 95% 0.13-52.76, p=0.041) and BMI (OR: 0.6 (CI 95% 0.41-0.89, p=0.009) were independently associated with sarcopenia of diabetes in multivariate analysis.

CONCLUSIONS

Only plasma XO was found to be independently associated with sarcopenia. XO can be important in the pathogenesis of sarcopenia in diabetes. Oxidative stress and antioxidant status might be associated with sarcopenia in diabetic older individuals but this association seems to be mediated by other factors. Further studies are needed on this subject.

Association between skeletal muscle mass and cardiorespiratory fitness in community-dwelling elderly men

BACKGROUND

Sarcopenia reduces physical ability and cardiorespiratory fitness (CRF), leading to poor quality of life.

AIM

The aim of this study was to investigate the relationship between skeletal muscle mass and CRF in elderly men.

METHODS

We assessed 102 community-dwelling men over 60 years old. Appendicular skeletal muscle mass (ASM) was determined using bioelectrical impedance analysis, and the skeletal muscle mass index (SMI) was calculated as ASM divided by the square of height. Subjects with an SMI less than 7.0 kg/m² were included in the sarcopenic group, as recommended by the Asian Working Group for Sarcopenia. To investigate CRF parameters, a cardiopulmonary exercise test was performed using the Bruce protocol. CRF parameters were subdivided into aerobic capacity, cardiovascular response, and ventilatory response.

RESULTS

Of the 102 subjects, 15 (14.7%) were included in the sarcopenic group. There were significant correlations between SMI and peak oxygen consumption (VO_2peak) (r = 0.597, p < 0.001), and between SMI and VO_2peak/weight (r = 0.268, p = 0.024). Moreover, there were positive correlations between SMI and first ventilatory threshold (VT1) (r = 0.352, p = 0.008) and between SMI and VT1/weight (r = 0.189, p = 0.039). Additionally, peak oxygen pulse (O₂pulse_peak) was significantly correlated with SMI (r = 0.558, p < 0.001). VO_2peak, VO_2peak/weight and O₂pulse_peak showed significant differences between the sarcopenic and non-sarcopenic groups (p < 0.05, all). In multiple linear regression analyses, the factor related to VO_2peak was SMI (β = 0.473, p < 0.001) and that related to O₂pulse_peak was also SMI (β = 0.442, p < 0.001).

DISCUSSION AND CONCLUSIONS

This study demonstrated that skeletal muscle mass might be closely associated with CRF. Therefore, sarcopenia should be appropriately managed to improve an individual's CRF.

Independent Association Between Cardio-Ankle Vascular Index and Sarcopenia in Older U.K. Adults

OBJECTIVES

To investigate the correlation between sarcopenia and arterial stiffness in Caucasians, centering on the relationship between skeletal mass index (SMI) and the cardio-ankle vascular index (CAVI) to assess the use of CAVI in predicting sarcopenia.

DESIGN CROSS-SECTIONAL SETTING

United Kingdom.

PARTICIPANTS

UK adults aged 45 years and over (N = 366, n = 177 male, n = 189 female).

MEASUREMENTS

Bioimpedance analysis was used to derive SMI. CAVI score was calculated using a vascular screening system. Handgrip strength was measured using a standard dynamometer.

RESULTS

Average CAVI was significantly correlated with SMI (correlation coefficient (r) = -0.285, p < .001), with higher correlation in women (r = -0.416, p < .001) than men (r = -0.214, p = .01). CAVI had the highest correlation with SMI from appendicular muscle (fat-free mass in men, r = -0.253, p = .002; predicted muscle mass in women, r = -0.436, p < .001). There was a significant difference in average CAVI between groups, with participants who were not sarcopenic having lower CAVI (8.98) than those who were sarcopenic (9.80) (p < .001, t-test). Linear regression was performed using SMI as the dependent variable. After adjustment for age, average CAVI was a significant predictor of SMI in women (beta = -0.332, p < .001) but not men.

CONCLUSION

Indices of sarcopenia are independently associated with a higher CAVI, with greater correlation in women than men. The CAVI can be used to assess overall vascular compliance and may be a useful operator-independent tool that can be used to measure sarcopenia and its cardiovascular implications in older adults. J Am Geriatr Soc 67:317-322, 2019.

Relationship Between Sarcopenia and Both Physical Activity and Lifestyle in Patients With Chronic Liver Disease

Background

Sarcopenia can affect the prognosis of patients with cirrhosis or hepatocellular carcinoma. Exercise therapy and nutritional therapy are carried out to prevent processing sarcopenia. In addition, changing lifestyle is also important. However, there are only few reports on the physical activities (PAs) and lifestyle of chronic liver disease patients and their association with sarcopenia. The aim of this study is to examine the relationship between sarcopenia in patients with chronic liver disease and both PA and lifestyle.

Methods

A total of 214 out-patients with chronic liver disease were enrolled into the present study. All patients were evaluated for with or without sarcopenia based on the sarcopenia diagnostic criteria of the Japan Society of Hepatology. Then, patient’s characteristics and laboratory parameters were divided into two groups with or without sarcopenia and compared. In continuous variable with significant difference in univariate analysis, cut-off value was calculated by receiver operating characteristic curve. We determined which factors were associated with sarcopenia in univariate analyses, and variables significant in the univariate analyses were entered in a multivariable logistic regression model.

Results

Patients with chronic liver disease had a prevalence of sarcopenia of 12.6% in this study. Sarcopenia patients were older (76.48 ± 6.69 versus 66.97 ± 11.19 years old; P < 0.01), had lower body mass index (BMI) (20.84 ± 2.44 versus 23.76 ± 3.72 kg/m²; P < 0.01), lower PA (6.6 (2.34 - 19.90) versus 16.5 (6.60 - 41.23) metabolic equivalents (METs)-h/week; P < 0.01) and longer total time sitting and lying on the day (7.43 ± 4.09 versus 5.68 ± 3.17 h/day; P = 0.01); retirement status (81.5% versus 48.1%; P < 0.01) and low frequency of driving (40% versus 20%; P = 0.01) were higher in sarcopenia patients than in non-sarcopenia patients. The independent predictive factors of sarcopenia, analyzed with logistic regression, were age (odds ratio (OR): 5.89, 95% confidence interval (CI): 2.15 - 16.20; P < 0.01), BMI (OR: 4.77, 95% CI: 1.87 - 12.10; P < 0.01) and PA (OR: 3.65, 95% CI: 2.15 - 16.20; P < 0.01).

Conclusion

Sarcopenia patients’ lifestyle characteristics were longer sedentary time and low frequency of driving, high retirement. Independent predictive factors of sarcopenia were elderly, low BMI and low PA. For these patients, intervention in the lifestyle for prevention of sarcopenia may be effective for patients with chronic liver disease.

Explanators of Sarcopenia in Individuals With Diabesity: A Cross-Sectional Analysis

BACKGROUND AND PURPOSE

Excess lower extremity intermuscular adipose tissue (IMAT), reduced strength, and functional limitations are common in obese individuals with and without diabetes (the former termed diabesity). Individuals with diabesity are particularly susceptible to accelerated sarcopenia, which may be underdiagnosed. The purpose of this study was to determine critical values for leg IMAT volume, plantar flexor (PF) muscle strength, and physical performance that help identify individuals with diabesity who have sarcopenia.

METHODS

Forty-three age- and sex-matched obese adults were studied: 12 with type 2 diabetes, 21 with diabetes and peripheral neuropathy, and 10 nondiabetic controls. Dual-energy x-ray absorptiometry-derived skeletal muscle index determined classification of sarcopenia. Leg fat (% IMAT), ankle (PF) peak torque, and power while ascending 10 steps, were used as explanators of sarcopenia. Receiver operating curves identified critical values for each explanator individually. Logistic regression models using all 3 explanators, and only PF torque and stair power, were also created. Receiver operating curve analyses identified the predicted probability that maximized each model's sensitivity and specificity. A leave-one-out cross validation was used to simulate the models' performance in an independent sample.

RESULTS AND DISCUSSION

Thirty-two participants were sarcopenic, and 11 were not. Critical values for individual explanators were 21% IMAT, 68 Nm PF torque, and 441 watts of stair power. Predicted probabilities of .76 and .67 were chosen as the optimal cutoff probabilities for the model combining all 3 explanators, and the model combining PF torque and stair power, respectively. The cross-validation analysis produced an accuracy of 82.4%, using the cutoff probability of .5, and an accuracy of 76.5% using the cutoff of 0.76. The area under the curve for the cross validation receiver operating curve analysis was 0.82. Critical values of leg % IMAT, PF torque, and stair power can classify individuals with diabesity as sarcopenic. The results of the cross validation give us confidence that the sample used in this study was representative of the target population, and suggests models created from this sample may perform well in externally derived data sets.

CONCLUSION

Clinicians may be able to use these critical values to select interventions that specifically target sarcopenia. Measures of % IMAT, PF torque, and stair power may offer a customized alternative to traditional sarcopenic classification systems, which may not be optimally suited to the common impairments among individuals with diabesity.

Reduced stress and improved physical functional ability in elderly with mental health problems following a horticultural therapy program

OBJECTIVES

This study aimed to determine the effects of a plant cultivation-based horticultural therapy program for elderly people with mental health problems.

DESIGN

Pre- and post-test design with experimental and control groups.

SETTING

Twenty-eight elderly Korean people with mental health problems participated from April to June 2017 at a farm located in Suwon, South Korea.

INTERVENTIONS

The participants were randomly assigned to either the control (n = 14) or horticultural therapy group (n = 14); the latter participated in once-weekly sessions of a previously designed 10-session horticultural therapy program.

MAIN OUTCOME MEASURES

The pre-test occurred 1 week before starting the horticultural therapy program. The post-test was completed within 1 week after finishing the final program session. Cortisol levels were measured in saliva samples collected from both groups. The Senior Fitness Test was used to assess physical functional ability in both groups.

RESULTS

In the horticultural therapy group, the cortisol levels decreased significantly from before to after the horticultural therapy program, and the post-test scores for six subtests of the Senior Fitness Test improved significantly. No significant improvements were seen in either measure in the control group.

CONCLUSIONS

This study demonstrates the potential ability of horticultural therapy to improve the stress levels and physical functional abilities of elderly people with mental health problems. In future studies, it would be interesting to verify the long-term effects of this horticultural therapy program and to compare its effects with regard to sex, age, and various mental symptoms.

Association between Sarcopenia and Metabolic Syndrome in Middle-Aged and Older Non-Obese Adults: A Systematic Review and Meta-Analysis

The associations between sarcopenia and metabolic syndrome (MetS) in non-obese middle-aged and older adults remain controversial. Thus, this meta-analysis aimed to evaluate the overall prevalence of MetS and the correlations between sarcopenia and MetS in middle-aged and older non-obese adults. We performed a systematic searched strategy using PUBMED, EMBASE and Web of Science databases for relevant observational studies investigating sarcopenia and MetS up to 11 May 2017. The polled prevalence of MetS and odds ratios with 95% confidence intervals (CI), as well as subgroup analyses were calculated using a random effects model. Twelve articles with a total of 35,581 participants were included. The overall prevalence of MetS was 36.45% (95% CI, 28.28–45.48%) in middle-aged and older non-obese adults with sarcopenia. Our analysis demonstrated a positive association between sarcopenia and MetS (OR = 2.01, 95% CI, 1.63–2.47). The subgroup analysis showed that both larger cohort size and the use of dual-energy X-ray absorptiometry to measure body composition can enhance the relationship. Our study revealed that a higher proportion of MetS in middle-aged and older non-obese people with sarcopenia. Moreover, sarcopenia was positively associated with MetS in this population. Further large-scale prospective cohort studies are needed to investigate the causality between sarcopenia and MetS.

Pathophysiological analyses of skeletal muscle in obese type 2 diabetes SDT fatty rats

Sarcopenia is the age-related decrease of muscle mass and function. Diabetes and obesity are known to be risk factors that exacerbate sarcopenia, but the underlying mechanism of diabetes-related sarcopenia is still unknown. Obese type 2 diabetes SDT fatty rats show early onset of severe diabetes and there have been no reports on the characteristics of their skeletal muscle. Therefore, pathophysiological analyses were performed for the skeletal muscle in these rats. Diabetic male SDT fatty rats were sacrificed at 8, 16, 24, 32 and 40 weeks of age. Age-matched Sprague Dawley (SD) rats were used as the normal control. In addition to biological blood parameters, the soleus and the extensor digitorum longus muscles were examined for muscle weight, histopathology, and protein synthesis and degradation. Muscle grip strength was also examined. These results revealed that the muscle weights of the SDT fatty rats were significantly decreased from 16 weeks of age. The mean cross-sectional area of muscle fibers in the SDT fatty rats decreased from 24 weeks of age. Increased intramyocellular lipid accumulation, identified by immunohistochemistry for adipophilin and TEM, was observed in the SDT fatty rats from 8 weeks of age. Plasma insulin-like growth factor (IGF)-1 levels and muscle strength in the SDT fatty rats decreased at 24 weeks of age and thereafter. These pathophysiological findings have been reported both in sarcopenia in aged humans and in patients with diabetes. In conclusion, the SDT fatty rat was considered to be a useful model for analysis of diabetes-related sarcopenia.

Flipping the Metabolic Switch: Understanding and Applying the Health Benefits of Fasting

OBJECTIVE

Intermittent fasting (IF) is a term used to describe a variety of eating patterns in which no or few calories are consumed for time periods that can range from 12 hours to several days, on a recurring basis. This review is focused on the physiological responses of major organ systems, including the musculoskeletal system, to the onset of the metabolic switch: the point of negative energy balance at which liver glycogen stores are depleted and fatty acids are mobilized (typically beyond 12 hours after cessation of food intake).

RESULTS AND CONCLUSIONS

Emerging findings suggest that the metabolic switch from glucose to fatty acid-derived ketones represents an evolutionarily conserved trigger point that shifts metabolism from lipid/cholesterol synthesis and fat storage to mobilization of fat through fatty acid oxidation and fatty acid-derived ketones, which serve to preserve muscle mass and function. Thus, IF regimens that induce the metabolic switch have the potential to improve body composition in overweight individuals. Moreover, IF regimens also induce the coordinated activation of signaling pathways that optimize physiological function, enhance performance, and slow aging and disease processes. Future randomized controlled IF trials should use biomarkers of the metabolic switch (e.g., plasma ketone levels) as a measure of compliance and of the magnitude of negative energy balance during the fasting period.

Physical Therapy Considerations for Chronic Kidney Disease and Secondary Sarcopenia

Chronic kidney disease (CKD) is a progressive condition that may negatively affect musculoskeletal health. These comorbidities may include malnutrition, osteoporosis, and decreased lean body mass. Secondary sarcopenia due to CKD may be associated with mobility limitations and elevated fall risk. Physical therapists are well-positioned among the health care team to screen for secondary sarcopenia in those with CKD and for the treatment of musculoskeletal comorbid conditions that may affect functional performance. Given the consequences of both low muscle mass and low bone mineral density, appropriate and timely physical therapy is important for fall risk assessment and intervention to minimize the susceptibility to bone fracture. While strength training has been studied less frequently than aerobic training for the management of secondary CKD conditions, evidence suggests that this patient population benefits from participation in strength training programs. However, the provision of a formal exercise prescription by a health care professional, along with formal implementation of an exercise program, may need to be more fully integrated into the standard plan of care for individuals with CKD.

Reversible Cognitive Frailty, Dementia, and All-Cause Mortality. The Italian Longitudinal Study on Aging

OBJECTIVES

Cognitive frailty, a condition describing the simultaneous presence of physical frailty and mild cognitive impairment, has been recently defined by an international consensus group. We estimated the predictive role of a "reversible" cognitive frailty model on incident dementia, its subtypes, and all-cause mortality in nondemented older individuals. We verified if vascular risk factors or depressive symptoms could modify this predictive role.

DESIGN

Longitudinal population-based study with 3.5- and 7-year of median follow-up.

SETTING

Eight Italian municipalities included in the Italian Longitudinal Study on Aging.

PARTICIPANTS

In 2150 older individuals from the Italian Longitudinal Study on Aging, we operationalized reversible cognitive frailty with the presence of physical frailty and pre-mild cognitive impairment subjective cognitive decline, diagnosed with a self-report measure based on item 14 of the Geriatric Depression Scale.

MEASUREMENTS

Incidence of dementia, its subtypes, and all-cause mortality.

RESULTS

Over a 3.5-year follow-up, participants with reversible cognitive frailty showed an increased risk of overall dementia [hazard ratio (HR) 2.30, 95% confidence interval (CI) 1.02-5.18], particularly vascular dementia (VaD), and all-cause mortality (HR 1.74, 95% CI 1.07-2.83). Over a 7-year follow-up, participants with reversible cognitive frailty showed an increased risk of overall dementia (HR 2.12, 95% CI 1.12-4.03), particularly VaD, and all-cause mortality (HR 1.39, 95% CI 1.03-2.00). Vascular risk factors and depressive symptoms did not have any effect modifier on the relationship between reversible cognitive frailty and incident dementia and all-cause mortality.

CONCLUSIONS

A model of reversible cognitive frailty was a short- and long-term predictor of all-cause mortality and overall dementia, particularly VaD. The absence of vascular risk factors and depressive symptoms did not modify the predictive role of reversible cognitive frailty on these outcomes.

Higher Muscle Strength Is Associated with Prolonged Survival in Older Patients with Advanced Cancer

BACKGROUND

Identifying predictors of treatment toxicity and overall survival (OS) is important for selecting patients who will benefit from chemotherapy. In younger patients with cancer, muscle mass and radiodensity are associated with treatment toxicity and OS. In this study, we investigated whether muscle mass, radiodensity, and strength were associated with treatment toxicity and OS in patients with advanced cancer aged 60 years or older.

MATERIALS AND METHODS

Before starting palliative chemotherapy, muscle mass and radiodensity were assessed using computed tomography scans and muscle strength was assessed using a hydraulic hand grip dynamometer. Treatment toxicity was defined as any toxicity resulting in dose reduction and/or discontinuation of treatment. Multiple logistic and Cox regression analyses were performed to study potential associations of muscle mass, radiodensity, and strength with treatment toxicity and OS, respectively.

RESULTS

The participants were 103 patients, with a mean age of 70 years, with advanced colorectal, prostate, or breast cancer. Muscle parameters were not significantly associated with treatment toxicity. Higher muscle strength was associated with longer OS (hazard ratio 1.03; 95% confidence interval 1.00-1.05). Muscle mass and radiodensity were not significantly associated with OS.

CONCLUSION

Higher muscle strength at the start of palliative chemotherapy is associated with significantly better OS in older patients with advanced cancer. None of the investigated muscle parameters were related to treatment toxicity. Future studies are needed to evaluate whether muscle strength can be used for treatment decisions in older patients with advanced cancer.

IMPLICATIONS FOR PRACTICE

This study in older patients with advanced cancer showed that adequate muscle strength is associated with longer overall survival. The results of this study imply that muscle strength might be helpful in estimating survival and therefore in identifying older patients who will benefit from anticancer treatment.

The effect of ARC ablation on skeletal muscle morphology, function, and apoptotic signaling during aging

Augmented apoptotic signaling can result in degradation of skeletal muscle proteins and loss of myonuclei, ultimately contributing to muscle atrophy and contractile dysfunction. Apoptosis repressor with caspase recruitment domain (ARC) is an anti-apoptotic protein highly expressed in skeletal muscle. Here we examined the role of ARC on age-related skeletal muscle apoptosis and wasting by utilizing an ARC-deficient mouse model. Aged mice displayed a number of morphological, phenotypic, and contractile alterations in both soleus and plantaris muscle with aging. Although no differences were found in proteolytic enzyme activity, ARC protein decreased while several anti-apoptotic proteins (e.g., BCL2, BCLXL, HSP70, and XIAP) and the release of mitochondrial housed protein (i.e., SMAC, AIF) increased in aged muscle. Importantly, ARC KO mice had low muscle weights and fewer fibers in soleus, with 2-year-old ARC KO mice displaying lower mitochondrial BCL2 protein along with augmented release of CYTC and SMAC in red/oxidative muscle. Overall, these results indicate that aged skeletal muscle undergoes atrophy as well as contractile and fiber type composition alterations despite an increase in anti-apoptotic protein expression. Although some mitochondrial-specific apoptotic alterations occurred in skeletal muscle due to ARC ablation over the lifespan, our data suggest that ARC may not have a large influence during skeletal muscle aging.

Association between sarcopenia with lifestyle and family function among community-dwelling Chinese aged 60 years and older

Background

Sarcopenia is defined as the age-related decline in skeletal muscle mass and function. The risk factors and causes of sarcopenia must be identified to develop prevention and treatment strategies for this syndrome. Our aim was to examine the association between sarcopenia with lifestyle and family function among community-dwelling Chinese people aged 60 years and older.

Methods

We conducted this study to evaluate sarcopenia among 834 community-dwelling Chinese individuals aged ≥60 years using the Asian Working Group for Sarcopenia (AWGS) criteria. The sociodemographic characteristics, food consumption patterns, habits of smoking, and alcohol consumption of the participants were collected using a general questionnaire, whereas physical activity was assessed using the International Physical Activity Questionnaire (IPAQ; long-form version). Family function was assessed using the Family APGAR scale. In addition, the association of sarcopenia with lifestyle and family function was examined using univariate and multivariate analyses.

Results

The total prevalence rate of sarcopenia was 10.6%. Female participants with sarcopenia had a lower frequency per week of nut consumption than those without sarcopenia (p < 0.05), whereas, for male participants, the differences in food consumption patterns of those with sarcopenia versus those without sarcopenia were not significant. Among the participants, the mean Family APGAR score was 8 (standard deviation [SD] = 0.92). For both sexes, participants with sarcopenia had lower family function scores than those without sarcopenia. In the multivariate model, after adjustment for all covariates, frequency per week of nut consumption (adjusted OR 0.724, 95% CI 0.532–0.985, P < 0.05) and Family APGAR score (adjusted OR 0.683, 95% CI 0.496–0.940, P = 0.019) were statistically significantly associated with sarcopenia. The relationship between other lifestyle habits and sarcopenia was not significant.

Conclusion

There was significant association between sarcopenia with intake of nuts and family function. Further studies should evaluate if adequate intake of nuts and a well-functioning family may be effective in lowering the risk of sarcopenia.