Sarcopenia is a skeletal muscle disease characterised by low muscle mass, strength and/or impaired physical function that is associated with a wide range of adverse outcomes including osteoporosis, falls, fractures, disability, hospitalization, loss of independence and quality of life and mortality, if left untreated.(1, 2) This is also growing evidence linking sarcopenia to many other chronic conditions, including type 2 diabetes, fatty liver disease, cognitive impairment and dementia, certain cancers (and post- treatment outcomes), cardiovascular disease and impaired immunity.(3–4) Despite its significant impact, awareness and knowledge about this disease amongst healthcare professionals (and the general public), including how to identify and treat/manage sarcopenia, remains low. There are currently no approved pharmacological agents for the treatment sarcopenia, but there is moderate-to-high level evidence informing clinical practice guidelines that multifaceted interventions incorporating resistance-based training with adequate nutrition focusing on high quality protein or multi-nutrient protein-based supplements can prevent and manage this disease.(1, 5–6) Meta-analyses of randomised controlled trials consistently demonstrate that progressive resistance training (at least twice weekly) is the most effective approach to elicit gains in muscle mass and strength (independent of age), with the provision of dietary protein or multi- nutrient protein-based supplements providing small added benefits(7). Emerging evidence also indicates that minimal dose exercise strategies (e.g., resistance/strength “snacking” activities) and limiting sedentary behaviours (breaking up prolonged sitting) may help to attenuate age-related muscle loss. With regards to nutritional factors, most guidelines for older adults recommend a protein intake of 1.2 to 1.6 g/kg/d (25-30g of protein per meal) incorporating 3-4g of leucine to support muscle health. However, the benefits of protein alone on muscle-related outcomes are modest and appear mostly limited to those with insufficient (deficient) intakes (levels) and/or who are sarcopenic, frail and/or malnourished. A wide range of other nutritional-related factors (with and without exercise) have been investigated, including β-hydroxy β-methylbutyrate (HMB), vitamin D, creatine, antioxidants, omega-3 fatty acids, and phospholipids, as well as multi-nutrient supplements and various diets (Mediterranean diet), dietary patterns and foods (dairy products). There is also growing evidence that altering the gut microbiota and the use of probiotics, prebiotics and synbiotics may enhance muscle health. This presentation will provide an update of the evidence related to these factors to help guide decision making for clinical management and provide an overview of the current criteria used to identify poor muscle health and sarcopenia, including a new muscle health monitoring and management algorithm we have developed.

It is estimated that more than one-tenth of adults aged ≥60 years are now classified as having sarcopenic obesity (SO), a clinical condition characterised by the concurrent presence of sarcopenia (low muscle mass and weakness) and obesity (excessive fat mass). Independently, sarcopenia and obesity are associated with a high risk of numerous adverse health outcomes including CVD and neurological conditions (e.g. dementia), but SO may confer a greater risk, exceeding either condition alone. This imposes a substantial burden on individuals, healthcare systems and society. In recent years, an increasing number of observational studies have explored the association between SO and the risk of CVD; however, results are mixed. Moreover, the pathophysiology of SO is governed by a complex interplay of multiple mechanisms including insulin resistance, inflammation, oxidative stress, hormonal shifts and alteration of energy balance, which may also play a role in the occurrence of various CVD. Yet, the exact mechanisms underlying the pathological connection between these two complex conditions remain largely unexplored. The aim of this review is to examine the association between SO and CVD. Specifically, we seek to: (1) discuss the definition, epidemiology and diagnosis of SO; (2) reconcile previously inconsistent findings by synthesising evidence from longitudinal studies on the epidemiological link between SO and CVD and (3) discuss critical mechanisms that may elucidate the complex and potentially bidirectional relationships between SO and CVD.

Loss of skeletal muscle strength and mass (sarcopenia) is common in older adults and associated with an increased risk of disability, frailty and premature death. Finding cost-effective prevention and treatment strategies for sarcopenia for the growing ageing population is therefore of great public health interest. Although nutrition is considered an important factor in the aetiology of sarcopenia, its potential for sarcopenia prevention and/or treatment is still being evaluated. Nutrition research for sarcopenia utilises three main approaches to understand muscle-nutrition relationships, evaluating: single nutrients, whole foods and whole diet effects – both alone or combined with exercise. Applying these approaches, we summarise recent evidence from qualitative and quantitative syntheses of findings from observational and intervention studies of healthy older adults, and those with sarcopenia. We consider protein supplements, whole foods (fruits and vegetables) and the Mediterranean diet as exemplars. There is some evidence of beneficial effects of protein supplementation ≥ 0·8 g/kg body weight/d on muscle mass when combined with exercise training in intervention studies of healthy and sarcopenic older adults. In contrast, evidence for effects on muscle function (strength and physical performance) is inconclusive. There is reasonably consistent epidemiological evidence suggesting benefits of higher fruits and vegetables consumption for better physical performance. Similarly, higher adherence to the Mediterranean diet is associated with beneficial effects on muscle function in observational studies. However, intervention studies are lacking. This review discusses how current evidence may inform the development of preventive and intervention strategies for optimal muscle ageing and nutritional public policy aimed at combatting sarcopenia.

The impact of computed tomography-defined sarcopenia on outcomes in head and neck cancer has been well described. Sarcopenic obesity (SO) (depleted muscle mass combined with obesity) may pose a more serious risk than either condition alone. We investigated SO and its impact on survival and critical weight loss (≥ 5 %) in patients with head and neck cancer who received curative radiotherapy (± other modalities). Retrospective analysis of computed tomography cross-sectional muscle at cervical (C3), thoracic (T2) and lumbar (L3) regions was conducted. Patients were grouped by BMI and sarcopenia status based on established thresholds. A total of 413 patients were included for analysis, the majority having oropharyngeal carcinoma (52 %), and 56 % received primary concurrent chemoradiotherapy. The majority of the cohort (65 %) was overweight or obese (BMI ≥ 25 kg/m2). Sarcopenia was found in 43 %, with 65 % having SO (n 116), equating to 28 % of the whole cohort. Critical weight loss was experienced by 58 % (n 238). A significantly higher proportion of patients with SO experienced critical weight loss (n 70 v. 19, P < 0·001) and were four times more likely to do so during treatment (OR 4·1; 95 % CI 1·5, 7·1; P = 0·002). SO was not found to impact on overall or cancer-specific survival; however, in patients with sarcopenia, those with SO had better overall survival (median 9·1 v. 7·0 years; 95 % CI 5·2, 16·8; P = 0·021). SO at the time of presentation in patients with head and neck cancer is predictive of critical weight loss during treatment, and muscle evaluation can be useful in identifying patients at nutritional risk regardless of BMI and obvious signs of wasting.

Malnutrition is a key factor in metabolic syndrome (MS) and sarcopenia, assessing the nutritional status of these patients is a pressing issue. The purpose of this study was to clarify sarcopenia and sarcopenic obesity in patients with MS based on nutritional status. This was a case–control study between MS/non-MS. Body composition was measured by dual-energy X-ray absorptiometry. Muscle function was assessed by handgrip strength, five times sit-to-stand test, gait speed test and short physical performance battery (SPPB). The Mini Nutritional Assessment (MNA) was performed to assess the nutritional status in the participants in this study. Overall, a total of 56 % and 13 % of participants suffered from possible sarcopenia and sarcopenia, respectively. There was a higher rate of possible sarcopenic obesity in the MS group than in the non-MS group (48·9 % v. 24·7 %, P < 0·01), and all the sarcopenia participants in the MS group had sarcopenic obesity. MNA score was significantly associated with sarcopenia status (P < 0·01). The MNA combined with body fat score showed better acceptable discrimination for detecting sarcopenic obesity and sarcopenia in MS (AUC = 0·70, 95 % CI 0·53, 0·86). In summary, there was a higher prevalence of possible sarcopenic obesity in MS, and all the MS patients with sarcopenia had sarcopenic obesity in the present study. We suggest that the MNA should be combined with body fat percentage to assess the nutritional status of MS participants, and it also serves as a good indicator for sarcopenia and sarcopenic obesity in MS.

Hand grip strength (HGS) is an important diagnostic tool for sarcopenia and a reliable predictor for age-related chronic diseases and mortality. Interventions in nutrition have been shown as a low-cost strategy to maintain muscular strength and mass. However, there are limited data on the effect of diet on HGS in Southeast Asian populations. This study aims to investigate the association of diet quality with HGS weakness and asymmetry in a multi-ethnic population in Singapore. This cross-sectional study used data from the Singapore Multi-Ethnic Cohort (n = 1547). Dietary data were collected using a validated semi-quantitative FFQ and summarised as the Dietary Quality Index – International (DQI-I). HGS was calculated as the maximum value of six measurements from both hands. HGS weakness and asymmetry were defined using well-recognised criteria. Multivariable linear regression and logistic regression were utilised for continuous and binary outcomes, respectively, adjusting for age, sex, ethnicity, physical activity and smoking status. It was found that the highest quartile of DQI-I was significantly associated with higher HGS (β = 1·11; 95 % CI 0·41, 1·82; Pfor trend < 0·001) and lower odds of HGS asymmetry (OR = 0·71; 95 % CI 0·53, 0·94; Pfor trend = 0·035) and both HGS weakness and asymmetry (OR = 0·50; 95 % CI 0·32, 0·76; Pfor trend = 0·004). Among the different components of DQI-I, only dietary adequacy was significantly associated with higher HGS (Pfor trend < 0·001) and lower odds for both HGS weakness and asymmetry (Pfor trend = 0·006). Our findings support that DQI-I, an indicator of overall diet quality, can be used to provide dietary guidelines for prevention and management of muscle wasting, sarcopenia and frailty.

Nuts are an important component of a healthy diet, but little has been known about their effects on muscle health. Therefore, this study examined the association between nut consumption and low muscle strength among Korean adults. This cross-sectional analysis was conducted using single 24-h recall and handgrip strength data from 3962 younger adults 19–39 years, 6921 middle-aged adults 40–64 years and 3961 older adults ≥65 years participated in the seventh cycle (2016–2018) of the Korea National Health and Nutrition Examination Survey. Low muscle strength was defined as handgrip strength <28 kg for men and <18 kg for women. Sex-specific OR were obtained for younger, middle-aged and older adults using multivariable logistic regression analyses. About one in four Korean adults were consuming nuts (using a culinary definition) with peanut being the most frequently consumed type. After adjustment for age, BMI, total energy intake, household income, alcohol consumption, smoking, resistance exercise, medical history and dietary protein intake, nut consumption was associated with the lower risk of low muscle strength among older adults ≥65 years (men: OR 0·55, 95 % CI (0·38, 0·79); women: OR 0·69, 95 % CI (0·51, 0·93)); however, this association was not observed among younger adults 19–39 years or middle-aged adults 40–64 years. Our results suggest that consuming nuts might be beneficial in lowering the risk of low muscle strength among Korean older adults.

The association between sarcopenia and kidney function remains poorly investigated. We aimed to evaluate the associations between sarcopenia status and kidney function (rapid kidney function decline and chronic kidney disease (CKD)) in middle-aged and older Chinese population. A total of 9375 participants from the China Health and Retirement Longitudinal Study 2011 were included in the cross-sectional analyses. A total of 5864 participants with eGFRcr-cys ≥ 60 ml/min per 1·73 m2 at baseline were included in the longitudinal analyses and were followed up in 2015. Sarcopenia status was defined according to the Asian Working Group for Sarcopenia 2019 criteria. In the cross-sectional analyses, possible sarcopenia and sarcopenia were significantly associated with an increased risk of CKD. During the 4 years of follow-up, 359 (6·12 %) participants experienced rapid decline in kidney function and 126 (2·15 %) participants developed CKD. After multivariable adjustment of baseline eGFRcr-cys level and other risk factors, possible sarcopenia (OR, 1·33; 95 % CI 1·01, 2·12) and sarcopenia (OR, 1·49; 95 % CI 1·05, 2·12) were associated with an increased risk of primary outcome (composite of rapid decline in kidney function (annualised decline in eGFRcr-cys ≥ 5 ml/min per 1·73 m2) and progression to CKD (eGFRcr-cys < 60 ml/min per 1·73 m2). Individuals with low muscle mass or low muscle strength alone also had an increased risk of rapid decline in kidney function and progression to CKD.

The aim of the present study was to assess the seasonal relationship between serum 25(OH)D concentration, lean mass and muscle strength. This was a secondary data analysis of a subgroup of 102 postmenopausal women participating in the 2006–2007 D-FINES (Vitamin D, Food Intake, Nutrition and Exposure to Sunlight in Southern England) study. The cohort was assessed as two age subgroups: <65 years (n=80) and ≥65 years (n=22). Outcome measures included lean mass (DXA), muscle strength (handgrip dynamometry) and serum 25(OH)D concentration (enzymeimmunoassay). Derived outcomes included appendicular skeletal muscle mass (ASM) and relative appendicular skeletal muscle index (RASM). Sarcopenia status was assessed using the European Working Group on Sarcopenia in Older People 2018 criteria. Non-parametric partial correlation using BMI as a covariate was used to evaluate the study aims. There were no statistically significant associations between total lean mass, ASM or RASM and 25(OH)D in any group at any season. There was a trend for handgrip strength to be positively associated with serum 25(OH)D concentration. There was a trend showing a higher prevalence of sarcopenia in women ≥65 years. Sarcopenia status appeared transient for five women. In conclusion, the present study found no significant association between vitamin D status and functional indicators of musculoskeletal health, which were additionally not affected by season.

This study aimed to identify patterns of anthropometric trajectories throughout life and to analyse their association with the occurrence of sarcopenia in people from the Longitudinal Study of Adult Health (ELSA-Brasil). It is a cross-sectional study involving 9670 public servants, aged 38–79 years, who answered the call for new data collection and exams, conducted approximately 4 years after the study baseline (2012–2014). Data sequence analysis was used to identify patterns of anthropometric trajectory. A theoretical model was elaborated based on the directed acyclic graph (DAG) to select the variables of minimum adjustment in the analysis of the causal effect between trajectory and sarcopenia. Poisson regression with robust variance was adopted for data analysis. The patterns of change in the anthropometric trajectory were classified in stable weight (T1); change to normal weight (T2); change to excess weight (T3); weight fluctuation (T4) and change to low weight (T5). The prevalence of sarcopenia in men and women who changed the anthropometric path for the low weight was twice as large when compared to participants with a stable weight trajectory. A protective effect of the excess weight trajectory was observed for the occurrence of sarcopenia in them. The results pointed to the need for health policies that encourage the proper management of body components in order to prevent and control obesity, as well as to preserve the quantity and quality of skeletal muscle mass throughout life, especially in older adults.

Sarcopenia is more common in the elderly and causes adverse outcomes with increased morbidity and mortality. This prospective cohort study assessed the association of sarcopenia risk with the severity of COVID-19 at the time of admission and during hospitalisation and the length of hospital stay. Two hundred patients (aged ≥ 60 years) who were hospitalised for COVID-19 were enrolled using consecutive sampling between 29 December 2020 and 20 May 2021. The sarcopenia score of the patients was assessed using the Strength, Assistance in walking, Rising from a chair, Climbing stairs, and Falls questionnaire. The severity of COVID-19 was determined using the modified National Early Warning Score (m-NEWS) system for 2019 n-CoV-infected patients at admission (T1), day three (T2) and at discharge (T3). Data were analysed using SPSS, version 22 and STATA, version 14. Of the 165 patients included, thirty four (20·6 %) were at risk of sarcopenia. The length of hospital stay was slightly longer in patients with sarcopenia risk, but the difference was not significant (P = 0·600). The adjusted OR of respiratory rate (RR) > 20 /min at T1 for the sarcopenia risk group was 6·7-times higher than that for the non-sarcopenic group (P = 0·002). According to generalised estimating equations, after adjusting for confounding factors, the m-NEWS score was 5·6 units higher in patients at risk of sarcopenia (P < 0·001). Sarcopenia risk could exacerbate COVID-19 severity and increase RR at admission, as well as the need for oxygen therapy at discharge.

Few studies have examined the association between coffee consumption and muscle mass; their results are conflicting. Therefore, we examined the association between coffee consumption and low muscle mass prevalence. We also performed an exploratory investigation of the potential effect modification by demographic, health status-related and physical activity-related covariates. This cross-sectional study included 2085 adults aged 40–87 years. The frequency of coffee consumption was assessed using a self-administered questionnaire. Muscle mass was assessed as appendicular skeletal muscle mass/height2 using a multifrequency bioelectrical impedance analyser. We defined low muscle mass using cut-offs recommended by the Asian Working Group for Sarcopenia. Multivariable-adjusted OR for low muscle mass prevalence were estimated using a logistic regression model. The prevalence of low muscle mass was 5·4 % (n 113). Compared with the lowest coffee consumption group (< 1 cup/week), the multivariable-adjusted OR (95 % CI) of low muscle mass prevalence were 0·62 (0·30, 1·29) for 1–3 cups/week, 0·53 (0·29, 0·96) for 4–6 cups/week or 1 cup/d and 0·28 (0·15, 0·53) for ≥ 2 cups/d (P for trend < 0·001). There were no significant interactions among the various covariates after Bonferroni correction. In conclusion, coffee consumption may be inversely associated with low muscle mass prevalence.

Fatigue is defined as a symptom leading to the inability to continue functioning at the expected activity level. It is a highly prevalent symptom, challenging to frame into monodimensional pathophysiological mechanisms. As a result, fatigue is often underestimated in the clinical setting and is wrongly considered an unavoidable consequence of ageing. Several potential mechanisms responsible for fatigue have been proposed, including sleep patterns, autonomic nervous system abnormalities and biological complexity. Inflammation and mitochondrial dysfunction are among the most promising mechanisms through which malnutrition may cause fatigue. Not surprisingly, fatigue is highly prevalent in inflammatory conditions (e.g. COVID-19 infection). The nutritional status may also represent a critical factor in the development and presentation of fatigue, which may mimic the exhaustion of the individual's metabolic reserves. For example, the insufficient dietary intake of energy and proteins may determine the catabolism of body fat and muscles, disrupt the homeostatic balance and cause the onset of fatigue. It is necessary to conduct research on fatigue. By characterising its pathophysiological mechanisms, it will be possible to (1) support the design and development of targeted interventions, (2) improve the quality of life of many persons by acting on the symptom and (3) reduce the direct and indirect costs of a burdening condition typical of advancing age. In the present review, we provide an overview of the role that nutrition may play as a determinant of fatigue in older people, also in the context of the COVID-19 pandemic.

Sarcopenic obesity is defined as the presence of high fat mass and low muscle mass combined with low physical function, and it is closely related with the onset of cardiovasular diseases (CVD). The existing anthropometric indices, which are being utilised in clinical practice as predictors of CVD, may also be used to screen sarcopenic obesity, but their feasibility remained unknown. Using cross-sectional data of 2031 participants aged 70–84 years (mean age, 75·9 ± 3·9 years; 49·2 % women) from the Korean Frailty and Aging Cohort Study, we analysed the association of anthropometric indices, including body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR) and weight-adjusted waist index (WWI) with sarcopenic obesity. Body composition was measured using dual-energy X-ray absorptiometry. Higher WWI, WHtR and WC quartiles were associated with higher risk of sarcopenic obesity; the odds ratio (OR) of sarcopenic obesity were highest in the fourth quartile of the WWI (OR: 10·99, 95 % CI: 4·92–24·85, Pfor trend < 0·001). WWI provided the best diagnostic power for sarcopenic obesity in men (area under the receiver operating characteristic curve: 0·781, 95 % CI: 0·751–0·837). No anthropometric indices were significantly associated with sarcopenic obesity in women. WWI was the only index that was negatively correlated with physical function in both men and women. WWI showed the strongest association with sarcopenic obesity, defined by high fat mass and low muscle mass combined with low physical function only in older men. No anthropometric indices were associated with sarcopenic obesity in older women.