Pathogenesis and Management of Sarcopenia

The shift of the paradigm between ageing and diseases

In the area of the Medical Sciences, the chronological age has always been, and still is, an indicator by which we try to understand the health status of an individual. However, besides considering people born with an already expressed disease, each human genome has sequence alterations called predisposing mutations; carriers of such genetic alterations have an increased risk of contracting diseases during their life. In addition, the exposome, i.e. the totality of environmental noxae (“hits”) to which our body is exposed throughout life (through ingestion, breathing, body surface hits, and psychosociological stress agents, etc.) contributes to increase gradually but inexorably the frailty of an organism, and this process is usually referred to as “physiological ageing”. This position paper proposes that we invert our visual angle and view the passage-of-time not as the cause of diseases, but consider the genome alterations present at birth and the noxae received during our life as the real major causes of ageing. The Biomedical Sciences are now increasingly unraveling the etiopathogenesis of most chronic degenerative diseases; thus, it will be possible to monitor and treat those that most contribute to the increased frailty of each person, which is now referred to with the misnomer “physiological ageing”. These concepts are not banal; indeed, they imply that we must try to avoid the causes of alterations that result later in chronic degenerative diseases. Thus, we should shift our attention from the cure to the prevention of alterations/diseases also to improve both the length and quality of our life. Moreover, this approach involves real personalized or individualized medicine, thus conferring a more direct benefit to each of us by finalizing either the cure or the monitoring of diseases.

Role of Helicobacter pylori infection in the manifestation of old age-related diseases

Helicobacter pylori is one of the most prevalent infection worldwide. It affects individuals of different age groups. Elderly people tend to resist eradication treatment and worsening of infection can lead to several gastric and non-gastric pathologies. Aging-associated cellular and molecular alteration can increase the risk of other pathologies such as osteoporosis, Alzheimer's disease, Parkinson's disease, respiratory and renal dysfunction, and cancer in geriatric patients, more than other age groups. This review article highlights some of the most common old age diseases and the role of H. pylori infection as a risk factor to worsen the conditions, presented by the molecular evidences of these associations. These studies can help clinicians to understand the underlying pathogenesis of the disease and identify high-risk patients, aiding clearer diagnosis and treatment.

Radiologically Defined Sarcopenia Affects Survival in Head and Neck Cancer: A Meta-Analysis

OBJECTIVE

To determine whether radiologically defined sarcopenia at the C3 or L3 level as measured by computed tomography or magnetic resonance imaging is prognostic of overall survival (OS) in head and neck cancers (HNCs).

METHODS

Literature searches of PubMed, Embase, and Scopus were conducted on July 12, 2019, to include articles written in the English language with no constraints on publication date. To be included in the analysis, articles had to report the prognostic impact of skeletal muscle mass measured radiologically at the C3 or L3 vertebral level in HNC patients; hazard ratios (HRs) for OS; 95% confidence intervals (CIs); be from a clinical trial, cohort, or case-control study; and have English full-text availability. Articles were reviewed in consensus by two reviewers, with disagreements reviewed by a third reviewer. Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis Of Observational Studies in Epidemiology Checklist guidelines were used for reporting. Study quality assessment was performed using Quality In Prognosis Studies tool. The random-effects DerSimonian and Laird method was used for meta-analysis.

RESULTS

Ten articles, nine retrospective and one prospective, were included in this meta-analysis (n = 2,181 patients). Significant differences were found in OS for HNC patients with sarcopenia (HR = 1.98; 95% CI: 1.64-2.39; P < .00001). No heterogeneity was detected in either the overall or subgroup analyses.

CONCLUSIONS

Radiologically defined sarcopenia is a negative predictor of OS in patients with HNC. Early detection of sarcopenia in cancer patients may help guide nutritional and adjuvant support to improve treatment outcomes.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:333-341, 2021.

Sarcopenia is Independently Associated with an Increased Risk of Peptic Ulcer Disease: A Nationwide Population-Based Study

Background and objective: Although obesity is associated with an increased risk of peptic ulcer disease (PUD), no study has evaluated the association of PUD with sarcopenia. The aim of this study was to evaluate the association of sarcopenia and obesity with PUD. Material and Methods: Data from the Korean National Health and Nutrition Examination Survey (KNHANES) IV and V for 2007–2012 were used. PUD history, dietary, alcohol consumption, smoking, physical activity patterns, and other socioeconomic factors were analyzed. Sarcopenia index (appendicular skeletal muscle mass (kg) ÷ body mass index (kg/m2)) and body fat mass were determined by dual-energy X-ray absorptiometry. Univariate and multivariate analyses were performed to evaluate the association of sarcopenia with the prevalence of PUD. Results: The 7092 patients were divided into the sarcopenic obesity (SO, n = 870), sarcopenic non-obesity (n = 2676), non-sarcopenic obesity (NSO, n = 2698), and non-sarcopenic non-obesity (NSNO, n = 848) groups. The prevalence of PUD in these groups was 70 (7.9%), 170 (7.4%), 169 (6.3%), and 47 (3.8%), respectively (p < 0.001). A crude analysis revealed that the prevalence of PUD was 2.2-fold higher in the SO group than in the NSNO group (odds ratio (OR), 2.2; 95% confidence interval (CI), 1.5–3.2), the significance of which remained after adjustment for age, sex, body mass index, and HOMA-IR (homeostatic model assessment insulin resistance) score (OR, 1.9; 95% CI, 1.3–2.7). Conclusion: In conclusion, in this nationally representative cohort, the combination of muscle and fat mass, as well as obesity, was associated with an increased risk of PUD.

The Role of Physical Activity for the Management of Sarcopenia in People Living with HIV

Sarcopenia is a physiopathological process associated with aging, caused by reduction of muscle strength, muscle quality and physical performance, and associated with an increased risk of falls, physical disability and premature death. There is no effective treatment for sarcopenia, but physical exercise seems to be highly effective at counteracting the decline in muscle mass and strength associated with aging. Recently, sarcopenia has been recognized as an emerging issue in people living with HIV (PLWH). Despite adequate treatment with combination antiretroviral therapy (cART), PLWH may exhibit an early occurrence of some aging-related conditions, including sarcopenia, frailty and falls, and this is likely resulting from high rates of comorbidities, high-risk behaviours, chronic immune activation and cART-specific factors. In this review, we discuss the potential mechanisms and the clinical relevance of sarcopenia in PLWH, and present data from longitudinal studies of physical activity in this population. Despite none of these studies having specifically addressed the benefits of physical exercise on sarcopenia, there is evidence that exercise is effective to increase aerobic capacity and muscle strength, and to improve body composition and inflammatory outcomes in PLWH. Therefore, the expected benefits of physical exercise are likely to translate into a successful and specific intervention for prevention and treatment of sarcopenia in this population.

Osteosarcopenic obesity, the coexistence of osteoporosis, sarcopenia and obesity and consequences in the quality of life in older adults ≥65 years-old in Greece

OBJECTIVE

We investigated the coexistence of sarcopenia and obesity in older adults≥65 years diagnosed with osteoporosis and the association with Quality of Life (QoL).

METHODS

A Cross-sectional survey has been performed on a randomized sample of 50 diagnosed osteoporotic elderly people from both sexes (Men=16; Women=34).

MEASUREMENTS

Quantitative ultrasound was conducted to identify osteoporosis and defined with a T score ≤2.5. Validated anthropometric equations were used in order to estimate body fat percentage and skeletal muscle mass so as to detect the reallocation of body fat and lean muscle. 10m gait speed and hand grip strength was measured in order to diagnose sarcopenia according to European Society for Clinical Nutrition and Metabolism (ESPEN) algorithm. The evaluation of QoL was conducted using a QoL questionnaire specific to osteoporosis. The data were analyzed with descriptive statistics and a chi-square test was performed to examine if Osteosarcopenic Obesity (OSO) is sex related and the correlation between OSO and QoL.

RESULTS

From the 50 participants, 40%(n=19) were classified as people with OSO and 60%(n=31) without OSO. From n=19 people that experienced OSO women represent 20% (n=9) and men 18% (n=9); with the latter had a greater decline in muscle mass than women, while women had lower BMD than men according to the z score. OSO is not related with sex (p>.05) and there is no significant association between OSO and QoL (p> .05 for all the domains of QoL questionnaire).

CONCLUSION

Osteoporosis in the elderly often coexists with reduced muscle mass and muscle strength as well as an increase in adiposity and was independently associated with QoL. People that experience OSO presenting lower functionality that increases the risk for falls and bone fractures originated from the decline in bone and muscle mass, and increased adiposity. Increased awareness of OSO may help develop efficient interventions and public health policies for healthier and more active elderly people.

Care plans for the older heart failure patient

Heart failure (HF) professionals are managing an older population with multiple, often interconnected comorbidities. The average age of the HF patient has increased substantially and many have a number of comorbidities. For the older HF patient, diligent planning of care has the potential to reduce hospitalization, improve quality of life and mortality; nevertheless, this vital component is often overlooked. Frailty, cachexia, sarcopenia, and cognitive impairment are all common in the older HF patient and require special care considerations. Many older HF patients live for many years with troublesome symptoms that could be better addressed through the incorporation of a palliative approach to care. Effective care plans can help patients maximize their health potential through both lifestyle and pharmacological interventions. However, current evidence remains scarce on what constitutes an optimal plan, therefore further studies are urgently needed. We review the care that could be implemented for the complex older HF patient with comorbidities.

Inflammaging as a common ground for the development and maintenance of sarcopenia, obesity, cardiomyopathy and dysbiosis

Sarcopenia, obesity and their coexistence, obese sarcopenia (OBSP) as well as atherosclerosis-related cardio-vascular diseases (ACVDs), including chronic heart failure (CHF), are among the greatest public health concerns in the ageing population. A clear age-dependent increased prevalence of sarcopenia and OBSP has been registered in CHF patients, suggesting mechanistic relationships. Development of OBSP could be mediated by a crosstalk between the visceral and subcutaneous adipose tissue (AT) and the skeletal muscle under conditions of low-grade local and systemic inflammation, inflammaging. The present review summarizes the emerging data supporting the idea that inflammaging may serve as a mutual mechanism governing the development of sarcopenia, OBSP and ACVDs. In support of this hypothesis, various immune cells release pro-inflammatory mediators in the skeletal muscle and myocardium. Subsequently, the endothelial structure is disrupted, and cellular processes, such as mitochondrial activity, mitophagy, and autophagy are impaired. Inflamed myocytes lose their contractile properties, which is characteristic of sarcopenia and CHF. Inflammation may increase the risk of ACVD events in a hyperlipidemia-independent manner. Significant reduction of ACVD event rates, without the lowering of plasma lipids, following a specific targeting of key pro-inflammatory cytokines confirms a key role of inflammation in ACVD pathogenesis. Gut dysbiosis, an imbalanced gut microbial community, is known to be deeply involved in the pathogenesis of age-associated sarcopenia and ACVDs by inducing and supporting inflammaging. Dysbiosis induces the production of trimethylamine-N-oxide (TMAO), which is implicated in atherosclerosis, thrombosis, metabolic syndrome, hypertension and poor CHF prognosis. In OBSP, AT dysfunction and inflammation induce, in concert with dysbiosis, lipotoxicity and other pathophysiological processes, thus exacerbating sarcopenia and CHF. Administration of specialized, inflammation pro-resolving mediators has been shown to ameliorate the inflammatory manifestations. Considering all these findings, we hypothesize that sarcopenia, OBSP, CHF and dysbiosis are inflammaging-oriented disorders, whereby inflammaging is common and most probably the causative mechanism driving their pathogenesis.

Frailty and Sarcopenia in Older Patients Receiving Kidney Transplantation

Kidney transplantation is the treatment of choice for most of the patients with end-stage renal disease (ESRD). It improves quality of life, life expectancy, and has a lower financial burden to the healthcare system in comparison to dialysis. Every year more and more older patients are included in the kidney transplant waitlist. Within this patient population, transplanted subjects have better survival and quality of life as compared to those on dialysis. It is therefore crucial to select older patients who may benefit from renal transplantation, as well as those particularly at risk for post-transplant complications. Sarcopenia and frailty are frequently neglected in the evaluation of kidney transplant candidates. Both conditions are interrelated complex geriatric syndromes that are linked to disability, aging, comorbidities, increased mortality, and graft failure post-transplantation. Chronic kidney disease (CKD) and more importantly ESRD are characterized by multiple metabolic complications that contribute for the development of sarcopenia and frailty. In particular, anorexia, metabolic acidosis and chronic low-grade inflammation are the main contributors to the development of sarcopenia, a key component in frail transplant candidates and recipients. Both frailty and sarcopenia are considered to be reversible. Frail patients respond well to multiprofessional interventions that focus on the patients' positive frailty criteria, while physical rehabilitation and oral supplementation may improve sarcopenia. Prospective studies are still needed to evaluate the utility of formally measuring frailty and sarcopenia in the older candidates to renal transplantation as part of the transplant evaluation process.

Musculoskeletal losses in patients with ankylosing spondylitis

Ankylosing spondylitis (AS) is one of the most common autoinflammatory diseases that lead to early disability and high premature mortality rates. Along with lower bone mineral density, patients with AS are characterized by muscle mass decrease, such as sarcopenia. Musculoskeletal losses due to chronic immune inflammation and limited physical functioning significantly worsen prognosis and result in an increased risk of falls and fractures in patients with AS.

The review considers the pathogenetic mechanisms of the relationship between AS and sarcopenia and the main approaches to treating degenerative changes in muscle tissue in patients with AS.

The Role of the Molecular Clock in Promoting Skeletal Muscle Growth and Protecting against Sarcopenia

The circadian clock has a critical role in many physiological functions of skeletal muscle and is essential to fully understand the precise underlying mechanisms involved in these complex interactions. The importance of circadian expression for structure, function and metabolism of skeletal muscle is clear when observing the muscle phenotype in models of molecular clock disruption. Presently, the maintenance of circadian rhythms is emerging as an important new factor in human health, with disruptions linked to ageing, as well as to the development of many chronic diseases, including sarcopenia. Therefore, the aim of this review is to present the latest findings demonstrating how circadian rhythms in skeletal muscle are important for maintenance of the cellular physiology, metabolism and function of skeletal muscle. Moreover, we will present the current knowledge about the tissue-specific functions of the molecular clock in skeletal muscle.

Accuracy and prognostic ability of the SARC-F questionnaire and Ishii's score in the screening of sarcopenia in geriatric inpatients

Sarcopenia remains poorly managed in clinical practice due to the lack of simple and accurate screening tools. This study aimed to identify the cutoff values of the SARC-F questionnaire and Ishii's score using the variables age, grip strength, and calf circumference in older inpatients in China to compare the accuracy of the two methods and to explore their predictive ability for adverse outcomes (rehospitalization, falls, fracture, and death). Hospitalized patients (n=138) aged ≥60 years were included. The accuracy of the two tools was evaluated using the reference diagnosis recommended by the Asian Working Group on Sarcopenia (assessing patients with measurements of muscle mass, handgrip strength, and usual gait speed). Follow-up data were obtained by telephone and clinical visits combined with the inpatient medical record system after discharge for at least one year. The results showed that the SARC-F score reached the highest Youden's index when a score of 3 was set as the cutoff value. Ishii's score presented a higher accuracy than SARC-F (area under the receiver operating curve: 0.78 vs 0.64, P=0.01). The Kaplan-Meier survival analysis demonstrated a higher cumulative incidence of rehospitalization in sarcopenic individuals compared to non-sarcopenic individuals according to SARC-F (log-rank test, P<0.001). Cox analysis revealed that SARC-F was an independent risk factor for rehospitalization (adjusted hazard ratio: 4.23, 95%CI: 2.12-9.79, P<0.001). The SARC-F and Ishii's scores might facilitate the early detection of sarcopenia and help identify older adults at risk for adverse outcomes in clinical practice.

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.

Women Reduce the Performance Difference to Men with Increasing Age in Ultra-Marathon Running

Age and sex are well-known factors influencing ultra-marathon race performance. The fact that women in older age groups are able to achieve a similar performance as men has been documented in swimming. In ultra-marathon running, knowledge is still limited. The aim of this study was to analyze sex-specific performance in ultra-marathon running according to age and distance. All ultra-marathon races documented in the online database of the German Society for Ultra-Marathon from 1964 to 2017 for 50-mile races (i.e., 231,980 records from 91,665 finishers) and from 1953 to 2017 for 100-mile races (i.e., 107,445 records from 39,870 finishers) were analyzed. In 50-mile races, race times were 11.74 ± 1.95 h for men and 12.31 ± 1.69 h for women. In 100-mile races, race times were 26.6 ± 3.49 h for men and 27.47 ± 3.6 h for women. The sex differences decreased with older age and were smaller in 100-mile (4.41%) than in 50-mile races (9.13%). The overall age of peak performance was 33 years for both distances. In summary, women reduced the performance difference to men with advancing age, the relative difference being smaller in 100-mile compared to 50-mile races. These findings might aid coaches and ultra-marathon runners set long-term training goals considering their sex and age.

Efficacy of Xianling Gubao capsule in treating sarco-osteopenia: Protocol for a systematic review and meta-analysis

BACKGROUND

Sarco-osteopenia (SOP) is a new type of geriatric syndrome, resulting from the combination of sarcopenia (SP) and osteoporosis (OP). Xianling Gubao capsule (XLGBC), made from several traditional Chinese medicine, is reported to have a therapeutic effect on diseases of bones and joints. This protocol will be designed to assess the efficacy of XLGBC in the treatment of SOP.

METHODS

Relevant randomized controlled trial literatures evaluating the effect of XLGBC on patients with SOP will be obtained by searching the following 7 electronic databases: Cochrane Library, PubMed, Embase, Chinese National Knowledge Infrastructure (CNKI), Chinese Scientific Journal Database (VIP), Chinese Biomedical and Medical Database (CBM), and Wanfang Database, from inception to March 2019. The primary outcomes will be bone mineral density, skeletal muscle mass index, handgrip strength, and gait speed. Stata V.13.0 software will be used for data synthesis and analysis, sensitivity analysis, subgroup analysis, and risk of bias assessment. Reporting bias will be evaluated utilizing a funnel, with Egger tests assessing funnel plot symmetries. Quality of evidence will be evaluated according to guidance of the Recommendations Assessment, Development, and Evaluation guideline.

RESULT

This study will provide a rational synthesis of current evidences for XLGBC on SOP.

CONCLUSION

The conclusion of this study will provide evidence to judge the effectiveness and safety of XLGBC on SOP.

ETHICS AND DISSEMINATION

This systematic review will be contributed to peer-reviewed publications, aiming to provide evidence about efficacy of XLGBC on SOP.

TRIAL REGISTRATION NUMBER

CRD42019128223.

Plasma Transthyretin as A Biomarker of Sarcopenia in Elderly Subjects

Skeletal muscle (SM) mass, the chief component of the structural compartment belonging to lean body mass (LBM), undergoes sarcopenia with increasing age. Decreased SM in elderly persons is a naturally occurring process that may be accelerated by acute or chronic nutritional deficiencies and/or inflammatory disorders, declining processes associated with harmful complications. A recently published position paper by European experts has provided an overall survey on the definition and diagnosis of sarcopenia in elderly persons. The present review describes the additional contributory role played by the noninvasive transthyretin (TTR) micromethod. The body mass index (BMI) formula is currently used in clinical studies as a criterion of good health to detect, prevent, and follow up on the downward trend of muscle mass. The recent upsurge of sarcopenic obesity with its multiple subclasses has led to a confused stratification of SM and fat stores, prompting workers to eliminate BMI from screening programs. As a result, investigators are now focusing on indices of protein status that participate in SM growth, maturation, and catabolism that might serve to identify sarcopenia trajectories. Plasma TTR is clearly superior to all other hepatic biomarkers, showing the same evolutionary patterns as those displayed in health and disease by both visceral and structural LBM compartments. As a result, this TTR parameter maintains positive correlations with muscle mass downsizing in elderly persons. The liver synthesis of TTR is downregulated in protein-depleted states and suppressed in cytokine-induced inflammatory disorders. TTR integrates the centrally-mediated regulatory mechanisms governing the balance between protein accretion and protein breakdown, emerging as the ultimate indicator of LBM resources. This review proposes the adoption of a gray zone defined by cut-off values ranging from 200 mg/L to 100 mg/L between which TTR plasma values may fluctuate and predict either the best or the worst outcome. The best outcome occurs when appropriate dietary, medicinal and surgical decisions are undertaken, resuming TTR synthesis which manifests rising trends towards pre-stress levels. The worst occurs when all therapeutic means fail to succeed, leading inevitably to complete exhaustion of LBM and SM metabolic resources with an ensuing fatal outcome. Some patients may remain unresponsive in the middle of the gray area, combining steady clinical states with persistent stagnant TTR values. Using the serial measurement of plasma TTR values, these last patients should be treated with the most aggressive and appropriate therapeutic strategies to ensure the best outcome.

Association between sarcopenia and rheumatological diseases

Sarcopenia (“sarx” for muscle, “penia” for loss) is an important problem in the elderly. Although muscle loss is a part of natural aging, excessive loss that limits physical activity is considered pathological. Sarcopenia is associated with age, malnutrition, physical inactivity, inflammatory stress and hormonal changes. Although relationships between sarcopenia and various chronic inflammatory diseases have been shown, the role of rheumatologic disease in sarcopenia development is currently unknown. Our aim in this mini-review was to increase the awareness of clinicians to sarcopenia, and to evaluate studies in which the relationship between sarcopenia and rheumatologic diseases was investigated. We also aimed to determine whether the available literature was sufficient to confirm a strong relationship between these conditions. Although our findings showed that diseases such as rheumatoid arthritis, osteoarthritis and systemic sclerosis may have a role in sarcopenia development and progress, the methodologies and results of the majority of studies were insufficient in determining direct causal relationships. We believe future studies would benefit from focusing on the factors and causes of sarcopenia, with a goal of determining the factors associated with rheumatologic disease that are most effective in sarcopenia development.

Validity and Reliability of the Newly Developed Surface Electromyography Device for Measuring Muscle Activity during Voluntary Isometric Contraction

Objective

The purpose of this study was to establish the validity and reliability of the newly developed surface electromyography (sEMG) device (PSL-EMG-Tr1) compared with a conventional sEMG device (BTS-FREEEMG1000).

Methods

In total, 20 healthy participants (10 males, age 30.3 ± 2.9 years; 10 females, age 22.3 ± 2.7 years) were recruited. EMG signals were recorded simultaneously on two devices during three different isometric contractions (maximal voluntary isometric contraction (MVIC, 40% MVIC, 80% MVIC)). Two trials were performed, and the same session was repeated after 1 week. EMG amplitude recorded from the dominant biceps brachii (BB) and rectus femoris (RF) muscles was analyzed for reliability using intrasession intraclass correlation coefficient (ICC). Concurrent validity of the two devices was determined using Pearson's correlation coefficient.

Results

Nonnormalized sEMG data showed moderate to very high reliability for all three contraction levels (ICC = 0.832–0.937 (BB); ICC = 0.814–0.957 (RF)). Normalized sEMG values showed no to high reliability (ICC = 0.030–0.831 (BB); ICC = 0.547–0.828 (RF)). sEMG signals recorded by the PSL-EMG-Tr1 showed good to excellent validity compared with the BTS-FREEEMG1000, at 40% MVIC (r = 0.943 (BB), r = 0.940 (RF)) and 80% MVIC (r = 0.983 (BB); r = 0.763 (RF)).

Conclusions

The PSL-EMG-Tr1 was performed with acceptable validity. Furthermore, the high accessibility and portability of the device are useful in adjusting the type and intensity of exercise.

The prevalence of muscle wasting (sarcopenia) in peritoneal dialysis patients varies with ethnicity due to differences in muscle mass measured by bioimpedance

BACKGROUND/OBJECTIVES

Sarcopenia is associated with increased mortality. European and North American recommended screening for low muscle mass uses gender specific cut points, with no adjustment for ethnicity. We wished to determine whether the prevalence of sarcopenia was altered by ethnicity in peritoneal dialysis (PD) patients.

SUBJECTS/METHODS

We measured appendicular lean mass indexed to height (ALMI) in PD patients by segmental bioimpedance and determined sarcopenia using different cut off points for reduced muscle mass.

RESULTS

We measured ALMI in 434 PD patients, 55.1% males, mean age 55.3 ± 16.2 years, 32.3% diabetic, 54.1% white, 23.7% Asian, 19.1% black. ALMI was lower in Asian women, compared to white and black women (6.4 ± 1.1 vs. 6.6 ± 1.0 and 6.9 ± 1.4 kg/m²), and lower in Asian men (7.5 ± 1.3 vs. 8.5 ± 1.2 and 8.7 ± 1.3 kg/m²), p < 0.001. Depending on the ALM/ALMI cut point; the prevalence of sarcopenia was greater in Asian patients (25.6-41.2% using North American or European cut points) compared to white (12.3-18.7%) and black patients (3.8-15.7%), p < 0.001, but <11% when using Asian-specific cut points. The prevalence of sarcopenia obesity (BMI ≥ 30 kg/m²) was <3%, for all groups. There was no association with duration of PD, dialysis prescription, residual renal function or small solute clearances.

CONCLUSIONS

There is no universally agreed consensus definition for loss of muscle mass (sarcopenia) and current European and North American recommended cut points for screening are adjusted only for gender. As body composition differs also with age and ethnicity, then ideally cut points should be based on age, gender and ethnicity normative values.

Gender, Success, and Drop-Out during a Resistance Exercise Program in Community Dwelling Old Adults

Background

Resistance exercise training can be effective against sarcopenia. We identified predictors of drop-out and compared physical outcomes between men and women after such training.

Methods

Subjects (N = 236, 73.7 ± 5.7 years) participated in a 12-week resistance exercise program. Outcome variables were measured at baseline and endpoint.

Results

Drop-out was 11.9% and not significantly different between genders. Drop-outs were significantly older and had poorer strength and physical function in comparison to completers. Anthropometrics, QoL, and cognitive function were not related to drop-out. According to multivariate analysis, gait speed and physical activity were the strongest predictors of drop-out. After the training, gains in lean mass or appendicular muscle were significantly higher in men than women; however relative gains in appendicular muscle as well as absolute improvements in strength and function were similar in men and women, respectively.

Conclusions

Participants who drop out are older, have poorer physical function, and are less physically active. Old women do not drop out more frequently than men and show meaningful improvements in relevant outcomes similar to men after such a training program. The trial is registered at the US National Library of Medicine (NCT01074879).

Upping the ante: working harder to address physical inactivity in older adults

PURPOSE OF REVIEW

Physical inactivity in older adults is associated with declining functional capacity, sarcopenia, metabolic changes, and cognitive changes. Current Physical Activity Guidelines recommend 150 min of moderate-intensity exercise along with strengthening and balance exercises. Despite the guidelines there is little evidence of a population-based change in physical activity.

RECENT FINDINGS

There is a growing body of research investigating the use of high-intensity interval training in older adult to improve health-related outcomes. Research indicates that high-intensity interval training confers greater benefit than moderate-intensity exercise and is acceptable and safe for older adults and those with various noncommunicable diseases.

SUMMARY

A major challenge to health systems is the growing number of people surviving into older age, many of whom have more than one noncommunicable disease. Physical inactivity is a modifiable risk factor for the development of noncommunicable diseases. Increasing participation in physical activity interventions, particularly those at a high intensity, appears to be a safe and feasible approach to reducing the demand on healthcare systems into the future.

Inflammation and age-associated skeletal muscle deterioration (sarcopaenia)

Ageing is accompanied by chronic inflammatory responses due to elevated circulatory inflammatory cytokine production. Several inflammatory cytokines have been shown to be responsible for a decrease in muscle mass. However, little is known about the possible relationship between inflammation and sarcopaenia. This review aims to summarise the existing evidence about inflammation and sarcopaenia. Sarcopaenia is defined as an age-related decrease of muscle mass and/or muscle strength; it is caused by multiple factors, such as skeletal muscle atrophy, neuromuscular junction degeneration, hormone imbalance, cytokine imbalance, protein synthesis and proteolysis. Several inflammatory cytokines have been considered to promote muscle loss; C-reactive protein levels are significantly upregulated in sarcopaenia and sarcopenic obesity, and high levels of interleukin-6 are associated with reduced muscle mass and muscle strength (the administration of interleukin-6 could lead to a reduction in muscle mass). Up-regulation of tumour necrosis factor-α expression is also related to the development of sarcopaenia. Signalling pathways, such as protein kinase B/mammalian target of rapamycin, Janus kinase/signal transducer and activator of transcription-5 and signal transducer and activator of transcription 3 signalling, involved in muscle metabolism are regulated by insulin-like growth factor-1, tumour necrosis factor-α and interleukin-6 respectively. In conclusion, the inflammatory cytokines produced during chronic inflammation due to ageing, may influence their respective related pathways, thus leading to age-related muscle deterioration.

The translational potential of this article

This review can provide more information for sarcopaenia medicine research in terms of anti-inflammation therapy.

Vitamin B12 deficiency might be related to sarcopenia in older adults

Sarcopenia and dynapenia are related to repeated falls, mobility restriction, depression, frailty, increased mortality and morbidity. The aim of this study is to evaluate the relationship between vitamin B12 deficiency and sarcopenia in older adults. 403 patients, who attended to outpatient clinic and underwent comprehensive geriatric assessment, were included study. All cases' skeletal muscle mass (SMM), walking speed and hand grip strength were recorded by bioimpedance, 4meter walking test and hand dynamometer respectively. The diagnosis of sarcopenia was defined according to the criteria of the European Working Group on Sarcopenia in Older People. Sarcopenia was accepted low SMM with low handgrip strength or low physical performance. Dynapenia was defined as handgrip strength <30kg (men) and <20kg (women). The prevalence of sarcopenia and dynapenia was 24.8% and 32.0%, respectively. In the patients with sarcopenia, mean age, osteoporosis and frailty were higher, and MMSE, and instrumental ADL scores were lower than the patients without sarcopenia (p<0.05). The frequency of sarcopenia and dynapenia were 31.6% and 35.4%, respectively, in patients with vitamin B12 levels <400pg/mL. In addition lean body mass, total skeletal mass and skeletal muscle mass index were lower in the patients with vitamin B12 levels <400pg/mL compared to higher than 400pg/mL (p<0.05). Sarcopenia, which results in lots of negative clinical outcomes in older adults, might be related to vitamin B12 deficiency. Therefore, these patients should be periodically examined for vitamin B12 deficiency due to the potential negative clinical outcomes such as sarcopenia in older adults.