Sarcopenic obesity in older adults: aetiology, epidemiology and treatment strategies

Obesity and visceral fat: Survival impact in high-grade endometrial cancer

BACKGROUND

Obesity is an important risk factor for the development of endometrial cancer (EC). Recent data showed that body fat distribution might be more relevant than Body Mass Index (BMI). High visceral fat percentage was shown to be an independent predictor for survival in EC, but mainly included grade 1-2 EC.

OBJECTIVE

To evaluate body fat distribution and its relation to outcome in high-grade endometrial cancer.

METHODS

Retrospective study in women diagnosed with high-grade EC between February 2006 and August 2017 at the Royal Cornwall Hospital who had abdominal CT-scan as part of routine diagnostic work-up. Subcutaneous abdominal fat volumes and visceral abdominal fat volumes were quantified based on CT-scan measurements, and visceral fat percentage calculated.

RESULTS

A total of 176 patients with high-grade EC were included. The median age was 70 years and median BMI was 29.4 kg/m². The majority of patients had non-endometrioid endometrial cancer (NEEC; 62 %). High visceral fat percentage was associated with poor overall- and disease-specific survival (p = 0.006 and p = 0.026 respectively) in NEEC patients, but not in high-grade endometrioid EC (EEC). The most frequent obesity comorbidities hypertension and diabetes mellitus were significantly associated with high BMI and high visceral fat percentage.

CONCLUSION

In high-grade EC, high visceral fat percentage was an independent predictor of poor survival only in NEEC. The strong correlation between high visceral fat and obesity-related comorbidities might be reflective of an unhealthy macroenvironment.

[Aging: a global, multidimensional and preventive approach]

Aging is physiological and begins very early. It can be accelerated by our lifestyle and by chronic diseases. There are over 300 "theories" of aging and many animal models have been developed ranging from yeast to more complex organisms. Civil age is not a reflection of an individual's physiological age. Starting from the age of 30 a decrease in organ function can be observed. The aging of an individual leads him to 3 states: vigourous, polypathological and dependent or frail. The state of fragility is reversible. We have to be an actor in our aging and no longer suffer it. The centenarians of the blue zones have achieved, culturally, active aging which has led them to successful aging.

Nonalcoholic fatty liver disease and sarcopenia: pathophysiological connections and therapeutic implications

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is currently one of the most common liver diseases worldwide. Recent data suggest that loss of skeletal muscle mass and function (i.e. sarcopenia) is highly prevalent and frequently overlooked in NAFLD patients. Experimental and clinical data suggest that the relationship between NAFLD and sarcopenia is pathophysiologically complex and bi-directional and there is a growing interest in unveiling how sarcopenia could influence NAFLD development and progression.

AREAS COVERED

PubMed/MEDLINE was searched for articles related to concomitant occurrence of NAFLD and sarcopenia between January 2013 and April 2020. Areas covered in this review include: (1) updated sarcopenia diagnosis strategy, (2) discussion of current data on pathophysiological connections between NAFLD and sarcopenia, and (3) analysis of current and future therapeutic implications of this knowledge.

EXPERT OPINION

Clinical studies describe a consistent association between NAFLD and sarcopenia, although a cause-effect relation remains to be determined. Active implementation of current diagnosis algorithms and optimized treatment can prevent sarcopenia related complications in subjects with NAFLD. Pathogenic pathways implicated in this relation are multiple and complex, a better understanding of them can provide novel biomarkers and targeted therapies that will hopefully have an important impact in NAFLD management.

Exploring the Impact of Obesity on Skeletal Muscle Function in Older Age

Sarcopenia is of important clinical relevance for loss of independence in older adults. The prevalence of obesity in combination with sarcopenia ("sarcopenic-obesity") is increasing at a rapid rate. However, whilst the development of sarcopenia is understood to be multi-factorial and harmful to health, the role of obesity from a protective and damaging perspective on skeletal muscle in aging, is poorly understood. Specifically, the presence of obesity in older age may be accompanied by a greater volume of skeletal muscle mass in weight-bearing muscles compared with lean older individuals, despite impaired physical function and resistance to anabolic stimuli. Collectively, these findings support a potential paradox in which obesity may protect skeletal muscle mass in older age. One explanation for these paradoxical findings may be that the anabolic response to weight-bearing activity could be greater in obese vs. lean older individuals due to a larger mechanical stimulus, compensating for the heightened muscle anabolic resistance. However, it is likely that there is a complex interplay between muscle, adipose, and external influences in the aging process that are ultimately harmful to health in the long-term. This narrative briefly explores some of the potential mechanisms regulating changes in skeletal muscle mass and function in aging combined with obesity and the interplay with sarcopenia, with a particular focus on muscle morphology and the regulation of muscle proteostasis. In addition, whilst highly complex, we attempt to provide an updated summary for the role of obesity from a protective and damaging perspective on muscle mass and function in older age. We conclude with a brief discussion on treatment of sarcopenia and obesity and a summary of future directions for this research field.

Personalised treatment for older adults with cancer: The role of frailty assessment

It is widely accepted in clinical practice that chronological age is a poor predictor of treatment tolerance and outcomes in older adults with cancer. Intrinsic vulnerability is more a function of underlying frailty, rather than chronological age. Frailty is a state of increased vulnerability to stressors, such as cancer and its treatment, which can lead to adverse health outcomes for patients. Capturing this heterogeneity in reserve capacity is the cornerstone of management in geriatricmedicine, but remains poorly understood or adopted in radiation oncology. A two-step approach, using a shorter screening tool, followed by full assessment for those who need it, is the mostresourceful way of implementing frailty assessment in radiotherapy departments. It is important for radiation oncology professionals to identify frailty and to use this information in multidisciplinary decision making in order to develop a personalised radiotherapy approach for the older person. There are many ways we can effectively use this information, such as considering treatment fractionation schedules that would limit the burden of travel for those with social frailty, or reviewing the range of modalities at our disposal, which might limit toxicity in the older person at high risk of deterioration during treatment. Frailty assessment is not carried out in many radiotherapy departments presently, but there are many international models to use as exemplars as to how it may be implemented in clinical practice. There are many opportunities for further research and role development in this field at the current time.

Sarcopenia in cancer: Risking more than muscle loss

Sarcopenia is characterised by progressive and extensive skeletal muscle degeneration and is associated with functional decline. Sarcopenia has primary and secondary aetiology, arising as a result of the ageing process or through chronic cytokine-mediated inflammation (associated with health conditions including cancer), respectively. Diagnosis of sarcopenia is dependent upon detection of reduced skeletal muscle strength, mass and performance. A combination of non-radiological and radiological methods can be used to assess each of these in turn to accurately diagnose sarcopenia. Sarcopenia is known to adversely affect outcomes of patients with various forms of cancer. Early identification of sarcopenia is imperative in improving patient care and overall prognosis. Various interventions, such as resistance exercise, nutritional support, and amino acid and vitamin supplementation have shown promise in the management of sarcopenia. However, further insight into novel interventions and indeed, assessment of the benefits of management of sarcopenia in terms of survival, are required to better support cancer patients.

Validation of a description of sarcopenic obesity defined as excess adiposity and low lean mass relative to adiposity

BACKGROUND

This study aims to assess the construct validity of a body composition-defined definition of sarcopenic obesity based on low appendicular lean mass relative to fat mass (ALMIFMI ) and high fat mass index (FMI) and to compare with an alternative definition using appendicular lean mass index (ALMI) and percent body fat (%BF).

METHODS

This is a secondary analysis of two cohort studies: the National Health and Examination Survey (NHANES) and the Health, Aging, and Body Composition study (Health ABC). Sarcopenic obesity was defined as low ALMIFMI combined with high FMI and was compared with a widely used definition based on ALMI and %BF cut-points. Body composition Z-scores, self-reported disability, physical functioning, and incident disability were compared across body composition categories using linear and logistic regression and Cox proportional hazards models.

RESULTS

Among 14, 850 participants from NHANES, patients with sarcopenic obesity defined by low ALMIFMI and high FMI (ALMIFMI -FMI) had above-average FMI Z-scores [mean (standard deviation): 1.00 (0.72)]. In contrast, those with sarcopenic obesity based on low ALMI and high %BF (ALMI-%BF) had below-average FMI Z-scores. A similar pattern was observed for 2846 participants from Health ABC. Participants with sarcopenic obesity based on ALMIFMI -FMI had a greater number of disabilities, worse physical function, and a greater risk of incident disability compared with those defined based on ALMI-%BF.

CONCLUSIONS

Body composition-defined measures of sarcopenic obesity defined as excess adiposity and lower-than-expected ALMI relative to FMI are associated with functional deficits and incident disability and overcome the limitations of using %BF in estimating obesity in this context.

COVID-19 and Acute Sarcopenia

The COVID-19 pandemic has had a devastating global impact, with older adults being most at risk of death from the disease. However, acute sarcopenia occurs in survivors of COVID-19; older adults and the most critically unwell patients are the most at risk. Acute sarcopenia is an under-recognised condition of acute muscle insufficiency, defined by declines in muscle function and/or quantity within six months, usually following a stressor event. This commentary reviews definition and mechanisms of acute sarcopenia in COVID-19 and suggests recommendations for research and clinical practice. Research should now focus on the longer-term consequences of acute sarcopenia in patients who have suffered from COVID-19. At the same time, clinicians need to be increasingly aware of the condition, and measurements of muscle strength, quantity, and physical performance should be embedded into clinical practice. Clinicians should consider the risks of acute sarcopenia when weighing up the risks and benefits of treatment (e.g. dexamethasone), and instigate multidisciplinary treatment including dietetics input.

Obesity, self-reported symptom severity, and quality of life in people with atrial fibrillation: A community-based cross-sectional survey

BACKGROUND AND AIMS

Intentional weight loss may reduce symptom severity of atrial fibrillation (AF) in relatively young AF patients with overweight. We examined whether symptom severity and quality of life (QoL) are associated with weight status in the general population with AF.

METHODS AND RESULTS

Patients with electrocardiogram-confirmed AF completed validated questionnaires: the EuroQol 5 Dimensions QoL questionnaire and the Toronto Atrial Fibrillation Severity Scale (AFSS). The AFSS assessed the AF burden scoring on AF-related symptoms and the total AF burden measured as a combination of duration, frequency, and severity of an irregular heartbeat. Generalized liner models examined the association of body mass index (BMI) with AF severity and QoL adjusting for confounders. Between 2018 and 2019, 882 of 1901 (46%) mailed questionnaires were returned completed. Participants had a mean (SD) age of 74 (10) years old and a BMI of 27.4 (5.6) kg/m². Sixteen percent reported having never experienced an irregular heartbeat. A 5 kg/m² higher BMI was associated with a 0.65 (95%CI: 0.25 to 1.06) higher symptom score, where 3 points represent a clinically relevant change in state. A 5 kg/m² higher BMI was associated with a -1.61 (95%CI: -2.72 to -0.50) lower QoL score. The coefficient of the total AF burden for a 5 kg/m² higher BMI was 0.17 (95% CI: -0.01 to 0.68).

CONCLUSION

BMI was positively associated with symptoms and negatively associated with one of the two measures of QoL, but not with the total AF burden. However, the strength of association was small and not clinically meaningful.

Trajectories of Body Composition during Advanced Aging in Consideration of Diet and Physical Activity: A 20-Year Longitudinal Study

This prospective study investigates age-dependent changes in anthropometric data and body composition over a period of two decades in consideration of physical activity and diet in community-dwelling subjects ≥60 years. Overall, 401 subjects with median follow-up time of 12 years were examined. Fat-free mass (FFM) and fat mass (FM) were analyzed using bioelectrical impedance analysis. Physical activity was assessed via a self-administered questionnaire. Dietary intake was examined by 3-day dietary records. Linear mixed-effects models were used to analyze the influence of age, sex, physical activity and energy/protein intake on anthropometric data and body composition by considering year of entry, use of diuretics and diagnosis of selected diseases. At baseline, median values for daily energy and protein intakes were 8.5 megajoule and 81 g and physical activity index was 1.7. After adjusting for covariates, advancing age was associated with parabolic changes indicating overall changes from age 60 to 90 years in women and men in body mass: −4.7 kg, −5.0 kg; body mass index: +0.04 kg/m², −0.33 kg/m²; absolute FFM: −2.8 kg, −3.5 kg; absolute FM: −1.8 kg, −1.2 kg and waist circumference: +16 cm, +12 cm, respectively. No age-dependent changes were found for upper arm circumference and relative (%) FFM. Dietary and lifestyle factors were not associated with changes in anthropometric or body composition parameters. In summary, the results indicate non-linear age-dependent changes in anthropometric data and body composition, which are largely unaffected by the degree of habitual physical activity and dietary protein intake in well-nourished community-dwelling subjects.

Lactobacillus-fermented milk products attenuate bone loss in an experimental rat model of ovariectomy-induced post-menopausal primary osteoporosis

AIM

In this study, we investigated the anti-osteoporotic effect of two fermented milk products (FMPs) fermented by Lactobacillus plantarum A41 and Lactobacillus fermentum SRK414 on a rat model of ovariectomy-induced post-menopausal primary osteoporosis.

METHODS AND RESULTS

The two Lactobacillus FMPs increased the bone volume and bone mineral density (BMD) in ovariectomized (OVX) rats, and normalized the bone biomarkers in the serum. Additionally, they altered the gene expression levels of bone-metabolism-related markers. Furthermore, the two Lactobacillus FMPs downregulated bone-apoptosis-related genes stimulated by ovariectomy. Interestingly, the Lactobacillus FMPs decreased the levels of inflammation markers in the serum, bone, ileum and colon of the rats. Gut bacterial populations were also affected upon FMP treatment due to increase in the abundance of the genus Lactobacillus and Faecalibacterium prausnitzii.

CONCLUSIONS

Milk products fermented by L. plantarum A41 and L. fermentum SRK414 can exhibit anti-osteoporotic effects on post-menopausal osteoporosis via regulating the expression of bone-metabolism-related markers.

SIGNIFICANCE AND IMPACT OF THE STUDY

The two Lactobacillus FMPs used in the study can be an ideal method that has its potential of treating post-menopausal osteoporosis instead of drug treatments.

Obesity and muscle may have synergic effect more than independent effects on brain volume in community-based elderly

OBJECTIVE

To evaluate the individual and combined effects of obesity and muscle mass on brain volume in a community-dwelling healthy older population.

METHODS

One thousand two hundred nine participants (M:F = 574:635, mean age 63.6 ± 6.9 years) were included. The cross-sectional area of visceral fat (VF), the height-adjusted appendicular skeletal muscle mass (ASM/height²), and the ratio of thigh muscle to visceral fat (TM/VF) represented obesity, muscle mass, and their integrated value, respectively. Linear regression analysis was performed to establish associations between 215 brain compartment volumes and VF, ASM/height², and TM/VF after adjusting for covariates.

RESULTS

On regression analysis, TM/VF had a positive correlation to the volumes of temporal lobe and cerebellum. TM/VF was associated with volumes of 10 subcompartments. TM/VF was positively correlated with the volumes of left entorhinal cortex, right temporal pole and inferior temporal gyrus related to cognition (p < 0.05, respectively), and the volumes of cerebellum and right pallidum related to movement (p < 0.05, respectively). However, VF had a negative correlation to temporal lobe volume and ASM/height² had no significant correlation to any of the brain lobes. VF and ASM/height² were correlated with volumes of 5 subcompartments and one subcompartment, respectively, CONCLUSIONS: TM/VF reflects the integrated effect of obesity and muscle mass and is associated with the volume of more brain regions compared to indices of obesity or muscle mass alone. The positive effect of muscle mass and the negative effect of obesity change the volumes of brain regions related to cognition and movement which were not significantly affected by obesity or muscle mass alone.

KEY POINTS

• If obesity and muscle mass were considered together, we could find more significant brain volume changes which were not found in obesity or muscle alone. • The ratio of thigh muscle to visceral fat was positively correlated with the volumes of entorhinal cortex, temporal pole, and inferior temporal gyrus related to cognition. • The ratio of thigh muscle to visceral fat was positively correlated with the volumes of cerebellum and pallidum related to movement.

Clinical screening and identification of sarcopenic obesity in adults with advanced knee osteoarthritis

BACKGROUND AND AIMS

Sarcopenic obesity (defined as low muscle mass and strength with high adiposity) requires attention in adults with advanced knee osteoarthritis (OA) due to implications on treatment outcomes. This study aimed to identify muscle function measures and patient characteristics associated with the presence of low muscle mass that could be used to screen and detect sarcopenic obesity in patients with knee OA in the clinical setting.

METHODS

Cross-sectional study of patients with knee OA and a body mass index (BMI) ≥30 kg/m². Body composition was measured in n = 151 patients (59% female, mean age 65.1 ± 7.9 years) using dual-energy x-ray absorptiometry. Appendicular skeletal muscle mass (ASM) adjusted by BMI and below established sex-specific cut-points was used to differentiate low muscle mass. Muscle function was assessed by 4-m gait speed, 6 min walk test, and maximal grip strength (absolute, and relative, adjusted by BMI). Logistic regression was used to assess the relationship between muscle function measures, patient characteristics, and low muscle mass. Receiver operating characteristic curves and area under the curve (AUC) were used to examine the final model and identify potential clinical cut-points.

RESULTS

Sex and relative grip strength were associated with low muscle mass (AUC 0.774, p < 0.001). Cut-points for low relative grip strength (<0.65 kg/m² in females and <1.1 kg/m² in males) were distinguished and used in combination with low muscle mass to screen and identify sarcopenic obesity. Patients with both low relative grip strength and low muscle mass (sarcopenic obesity) had impaired mobility and quality of life.

CONCLUSION

Relative grip strength shows promise as a clinical screening measure for sarcopenic obesity in patients with knee OA.

High Visceral Fat Area Attenuated the Negative Association between High Body Mass Index and Sarcopenia in Community-Dwelling Older Chinese People

The association between obesity and sarcopenia remains controversial. The present study was conducted to explore the associations among body mass index (BMI), visceral fat area (VFA), and sarcopenia in older people and analyze their potential mechanisms. This cross-sectional study included 861 community-dwelling older Chinese people from three regions of China. BMI, VFA, muscle mass, muscle strength, physical performance, body composition, and metabolic markers were measured. Muscle mass and muscle strength were positively correlated with BMI, but were negatively correlated with VFA. Simple overweight/obesity was negatively associated with sarcopenia (OR = 0.07, 95% CI = 0.03~0.18), and the OR value was lower than combined obesity (OR = 0.16, 95% CI = 0.09~0.28). Fat free mass and total body protein were positively associated with high BMI but negatively associated with high VFA. Furthermore, high VFA was adversely associated with some metabolic risk factors of sarcopenia. Combination of BMI and VFA increased diagnostic efficiency of low muscle mass and sarcopenia. In conclusion, high BMI was negatively associated with sarcopenia, while high VFA attenuated the negative association between high BMI and sarcopenia. The opposite association may partially be attributed to their different associations with body composition and metabolic risk factors of sarcopenia. Therefore, bedsides BMI, VFA and its interaction with BMI should be considered in sarcopenia prevention.

Cross-Talk between Diet-Associated Dysbiosis and Hand Osteoarthritis

Hand osteoarthritis (OA) is a degenerative joint disease which leads to pain and disability. Recent studies focus on the role of obesity and metabolic syndrome in inducing or worsening joint damage in hand OA patients, suggesting that chronic low-grade systemic inflammation may represent a possible linking factor. The gut microbiome has a crucial metabolic role which is fundamental for immune system development, among other important functions. Intestinal microbiota dysbiosis may favour metabolic syndrome and low-grade inflammation-two important components of hand OA onset and evolution. The aim of this narrative is to review the recent literature concerning the possible contribution of dysbiosis to hand OA onset and progression, and to discuss the importance of gut dysbiosis on general health and disease.

Prevalence and risk factors of primary sarcopenia in community-dwelling outpatient elderly: a cross-sectional study

No previous study has investigated the prevalence and risk factors for primary sarcopenia in outpatient setting. This study aims to evaluate the prevalence and factors associated with primary sarcopenia in outpatient elderly. Additionally, we compared the severity of sarcopenia based on the 2014 and 2019 Asian Working Group for Sarcopenia (AWGS) criteria. This cross-sectional study was performed in 330 subjects aged over 60 years in an outpatient setting. The muscle strength, muscle performance and muscle mass were assessed using the handheld dynamometer, 6-m gait speed, and bioelectrical impedance analysis, respectively. The prevalence of sarcopenia was 10% as per the 2014 and 2019 AWGS criteria. The development of sarcopenia was positively correlated with the age with an odds ratio (OR) of 6.87 [95% confidence interval (CI) 1.63–28.88] in the middle-old group (70–79 years), and 13.71 (95%CI 3.66–51.41; p = 0.009) in the very old group (≥ 80 years). Prefrailty and low physical activity were significantly associated with sarcopenia with an OR of 4.75 (95%CI 1.90—11.89) in prefrailty, 15.35 (95%CI 1.69–139.47) in the middle activity group, and 17.99 (95%CI 1.95–165.73) in the lowest activity group. In conclusion, primary sarcopenia was found in one-tenth of outpatient elderly. Age, prefrailty, and low activity were independent factors associated with sarcopenia.

Incident Impaired Cognitive Function in Sarcopenic Obesity: Data From the National Health and Aging Trends Survey

Objectives

The prevalence of obesity with sarcopenia is increasing in adults aged ≥65 years. This geriatric syndrome places individuals at risk for synergistic complications that leads to long-term functional decline. We ascertained the relationship between sarcopenic obesity and incident long-term impaired global cognitive function in a representative US population.

Design

A longitudinal, secondary data set analysis using the National Health and Aging Trends Survey.

Setting

Community-based older adults in the United States.

Participants

Participants without baseline impaired cognitive function aged ≥65 years with grip strength and body mass index measures.

Methods

Sarcopenia was defined using the Foundation for the National Institutes of Health Sarcopenia Project grip strength cut points (men <35.5 kg; women <20 kg), and obesity was defined using standard body mass index (BMI) categories. Impaired global cognition was identified as impairment in the Alzheimer's Disease-8 score or immediate/delayed recall, orientation, clock-draw test, date/person recall. Proportional hazard models ascertained the risk of impaired cognitive function over 8 years (referent = neither obesity or sarcopenia).

Results

Of the 5822 participants (55.7% women), median age category was 75 to 80, and mean grip strength and BMI were 26.4 kg and 27.5 kg/m², respectively. Baseline prevalence of sarcopenic obesity was 12.9%, with an observed subset of 21.2% participants having impaired cognitive function at follow-up. Compared with those without sarcopenia or obesity, the risk of impaired cognitive function was no different in obesity alone [hazard ratio (HR) 0.98; 95% confidence interval (CI) 0.82-1.16]), but was significantly higher in sarcopenia (HR 1.60; 95% CI 1.42-1.80) and sarcopenic obesity (HR 1.20; 95% CI 1.03-1.40). There was no significant interaction term between sarcopenia and obesity.

Conclusions

Both sarcopenia and sarcopenic obesity are associated with an increased long-term risk of impaired cognitive function in older adults.

Role of Oxidative Stress in Hepatic and Extrahepatic Dysfunctions during Nonalcoholic Fatty Liver Disease (NAFLD)

Nonalcoholic fatty liver disease (NAFLD) is a pathology that contains a broad liver dysfunctions spectrum. These alterations span from noninflammatory isolated steatosis until nonalcoholic steatohepatitis (NASH), a more aggressive form of the disease characterized by steatosis, inflammatory status, and varying liver degrees fibrosis. NAFLD is the most prevalent chronic liver disease worldwide. The causes of NAFLD are diverse and include genetic and environmental factors. The presence of NASH is strongly associated with cirrhosis development and hepatocellular carcinoma, two conditions that require liver transplantation. The liver alterations during NAFLD are well described. Interestingly, this pathological condition also affects other critical tissues and organs, such as skeletal muscle and even the cardiovascular, renal, and nervous systems. Oxidative stress (OS) is a harmful state present in several chronic diseases, such as NAFLD. The purpose of this review is to describe hepatic and extrahepatic dysfunctions in NAFLD. We will also review the influence of OS on the physiopathological events that affect the critical function of the liver and peripheral tissues.

Melatonin supplementation in the management of obesity and obesity-associated disorders: A review of physiological mechanisms and clinical applications

Despite the evolving advances in clinical approaches to obesity and its inherent comorbidities, the therapeutic challenge persists. Among several pharmacological tools already investigated, recent studies suggest that melatonin supplementation could be an efficient therapeutic approach in the context of obesity. In the present review, we have amalgamated the evidence so far available on physiological effects of melatonin supplementation in obesity therapies, addressing its effects upon neuroendocrine systems, cardiometabolic biomarkers and body composition. Most studies herein appraised employed melatonin supplementation at dosages ranging from 1 to 20 mg/day, and most studies followed up participants for periods from 3 weeks to 12 months. Overall, it was observed that melatonin plays an important role in glycaemic homeostasis, in addition to modulation of white adipose tissue activity and lipid metabolism, and mitochondrial activity. Additionally, melatonin increases brown adipose tissue volume and activity, and its antioxidant and anti-inflammatory properties have also been demonstrated. There appears to be a role for melatonin in adiposity reduction; however, several questions remain unanswered, for example melatonin baseline levels in obesity, and whether any seeming hypomelatonaemia or melatonin irresponsiveness could be clarifying factors. Supplementation dosage studies and more thorough clinical trials are needed to ascertain not only the relevance of such findings but also the efficacy of melatonin supplementation.

Prospective study on sedentary behaviour patterns and changes in body composition parameters in older women: A compositional and isotemporal substitution analysis

BACKGROUND & AIMS

The aims of this study were to examine the prospective compositional associations between sedentary behaviour (SB) patterns and longitudinal changes in body composition parameters, and to use compositional isotemporal substitution modelling to analyse the longitudinal changes in body composition parameters associated with time reallocation from SB to physical activity (PA) in older women.

METHODS

The study included women aged 60 years and older (n = 182) with valid data at baseline and at the subsequent 7-year follow-up. For both time points, the ActiGraph GT1M accelerometer was used for SB and PA assessments and multi-frequency bioimpedance analysis was used to assess the body composition parameters related to adiposity and muscle mass. Compositional regression models were used to analyse the associations between proportion of time spent in sedentary bouts of different duration and longitudinal changes in body composition parameters. A compositional isotemporal substitution model was created to estimate the differences in body composition parameters associated with one-to-one time reallocations between baseline SB and PA.

RESULTS

A significant increase in fat mass index (β_ilr1 = 0.61, 95% confidence interval [CI]: 0.18, 1.04) and visceral adipose tissue (β_ilr1 = 6.01, 95% CI: 1.52, 10.5) was associated with a higher baseline proportion of time spent in long sedentary bouts (i.e. sedentary bout of ≥30 min). Reallocating 1 h/week and 3.5 h/week from the time spent in long sedentary bouts in favour of light PA was associated with a significant decrease in fat mass index by 0.78% (95% CI: 0.24, 1.32) and 3.13% (95% CI: 0.97, 5.29), respectively. No association was found for indicators of muscle mass.

CONCLUSIONS

This study suggests that long-term adiposity status could be improved by increasing the proportion of time spent in light PA at the expense of time spent in prolonged SB. This finding may help in designing more effective and feasible interventions for the maintenance of healthy body composition in advanced age.

Addressing Obesity to Promote Healthy Aging

The population worldwide is aging and prevalence of obesity in this population is increasing. The range of consequences that effect these at-risk patients include increased risk of falls, fractures, reduced quality of life, and cognitive decline. This article describes the epidemiology of obesity, risks and benefits of weight loss, and importance of treating obesity to help promote healthy aging. Health care professionals should encourage older adults with obesity to implement healthy lifestyle behaviors including exercise and diet routine. Treating obesity in older adults mitigates the significant public health crisis, and reduces health care utilization and risk of long-term adverse events.

Are body fat and inflammatory markers independently associated with age-related muscle changes?

BACKGROUND & AIMS

A growing number of studies have shown that body fat and inflammation are associated with age-related changes in body muscle composition. However, most of these studies did not control for potential confounders. The aim was to determine whether there is an association between body fat and inflammatory cytokines with muscle mass/strength decline in community-dwelling older adults.

METHODS

Anthropometric, physical and functionality variables were collected. Nutritional status was assessed by the MNA form. Dynapenia was assessed with handgrip strength on the dominant hand using a dynamometer. Sarcopenia was determined using adapted criteria from the European Working Group on Sarcopenia in Older People 2 (EWGSOP2). Inflammatory cytokines were evaluated in plasma using a multiplex assay. Associations to muscle mass/strength decline were analyzed using a multinominal logistic regression, adjusted for potential confounders.

RESULTS

We recruited a convenience sample of 311 adults aged 60 years or older. Most of subjects were sufficiently active females with a median age of 68 years (interquartile range [IQR], 64-74 years), whereas about a half (46.3%) were at risk of malnutrition. The prevalence of dynapenia was 38.3%, whereas sarcopenia was 13.2%. After controlling for potential confounders, we found that relative fat mass index is independently associated with sarcopenia. Loss of strength was independently associated only with female sex, lower physical activity, worse nutrition and IL-10/TNF-α ratio, whereas female sex, an insufficiently active lifestyle and relative fat mass index were the key determinants of sarcopenia.

CONCLUSIONS

These findings highlight the importance of physical activity and healthy diet as effective interventions to prevent muscle mass/strength decline, and points to IL-10/TNF-α ratio and body fat as independently associated factors for dynapenia and sarcopenia, respectively.

Scientific evidence underlying contraindications to the ketogenic diet: An update

First identified as a feasible treatment for intractable epilepsy, the ketogenic diet (KD) has recently gained popularity thanks to growing evidence on applications such as weight loss, most importantly, but also NAFLD, cancer, neurologic conditions and chronic pain. As with any treatment, whether pharmacologic or not, the KD might not be an appropriate intervention for every individual, and a number of contraindications have been proposed, now deeply rooted into clinical practice, excluding de facto many patients that could benefit from its use. However, many of these concerns were expressed due to the absence of clinical studies conducted on fragile populations, and an assessment of lately emerged evidence relative to KD safety is currently lacking and much needed. We herein provide a critical revision of the literature behind each safety alert, in order to guide through the treatment options in the case of subjects with an indication to the KD and a borderline safe situation. Based on available evidence, the possible use of this diet as a therapeutic intervention should be assessed on a patient-to-patient basis by adequately skilled medical doctors, keeping in mind current recommendations, but reading them through the knowledge of the current state of the art.

Barriers to eating are associated with poor physical function in older women

Older adults have physical and social barriers to eating but whether this affects functional status is unknown. We examined associations between eating barriers and physical function in the Women's Health Initiative (WHI). In 2012-14, a subset of alive and participating women (n = 5910) completed an in-home examination including the Short Physical Performance Battery (SPPB) (grip strength, balance, timed walking speed, chair stand). WHI participants complete annual mailed questionnaires; the 2013-14 questionnaire included items on eating alone, eating < two meals/day, dentition problems affecting eating, physical difficulties with cooking/shopping and monetary resources for food. Linear regression tested associations of these eating barriers with SPPB, adjusting for BMI, age, race/ethnicity, and medical multimorbidities. Over half (56.8%) of participants were ≥ 75 years, 98.8% had a BMI ≥ 25.0 kg/m2 and 66% had multimorbidities. Eating barriers, excluding eating alone, were associated with significantly lower total (all p < .001) and component-specific, multivariate-adjusted SPPB scores (all p < .05). Compared to no barriers, eating < two meals/day (7.83 vs. 8.38, p < .0002), dentition problems (7.69 vs. 8.38, p < .0001), inability to shop/prepare meals (7.74 vs. 8.38, p < .0001) and insufficient resources (7.84 vs. 8.37 p < .001) were significantly associated with multivariate-adjusted mean SPPB score < 8. Models additionally adjusting for Healthy Eating Index-2010 had little influence on scores. As barriers increased, scores declined further for grip strength (16.10 kg for 4-5 barriers, p = .001), timed walk (0.58 m/s for 4-5 barriers, p = .001) and total SPPB (7.27 for 4-5 barriers, p < .0001). In conclusion, in this WHI subset, eating barriers were associated with poor SPPB scores.

3D UTE bicomponent imaging of cortical bone using a soft-hard composite pulse for excitation

PURPOSE

To evaluate 3D UTE bicomponent imaging of cortical bone ex vivo and in vivo using a newly designed soft-hard composite pulse for excitation.

METHODS

Chemical shift artifacts, presenting as fat-water oscillation or combination-induced signal oscillation, significantly reduce the accuracy of quantitative UTE bicomponent analysis of cortical bone. To achieve fat suppression for more reliable bicomponent analysis, a newly developed soft-hard excitation pulse was used with UTE imaging and compared with a single rectangular pulse excitation without and with a conventional fat saturation (FatSat) module. These 3 sequences were applied to 8 bovine bone samples without marrow fat, 3 bovine bone samples with marrow fat, and tibial midshafts of 5 healthy human volunteers. Bicomponent analyses were performed in both ex vivo and in vivo studies.

RESULTS

The soft-hard pulse provided comparable fat suppression, but much reduced bone signal attenuation compared with the FatSat module. Better bicomponent T 2 ∗ fitting was also achieved with the soft-hard excitation pulse because it greatly reduced chemical shift artifacts and outperformed the single rectangular pulse without or with FatSat. Although the FatSat module reduced fat signals and related fat-water oscillation, the water signals were significantly attenuated with more than 40% reduction due to direction saturation. For the inner layer of tibial midshaft in healthy volunteers, fitting errors increased from 3.78% for the soft-hard pulse to 11.43% and 5.16%, respectively, for the single rectangular pulse without and with the FatSat module.

CONCLUSION

The 3D UTE sequence with a new soft-hard excitation pulse allows more reliable bicomponent imaging of cortical bone.

A Community-Based Feasibility Study of Weight-Loss in Rural, Older Adults with Obesity

This study was a 12-week feasibility weight-loss intervention consisting of caloric restriction and aerobic/resistance exercise in older adults with obesity (body mass index ≥ 30 kg/m²) in a geographically isolated area. Primary outcomes assessed weight and physical function. Mean age was 71.0 ± 5.1 years (67% female). Individuals completed 100% of all assessments, attended 88% of the physical therapy classes and 89% of the nutrition sessions. Level of satisfaction (5-point Likert) was high (5.0, 1 - low; 5 - high). Weight decreased from 93.7 ± 9.7 to 89.4 ± 4.0 kg (p < 0.001). Mean BMI and waist circumference decreased, respectively, from 35.4 ± 3.4 to 33.6 ± 3.7 (p < 0.001), and 116.3 ± 7.5 to 108.7 ± 9.2 cm (p = 0.002). Grip strength, gait speed, and 5-times sit-to-stand time all improved from 29.2 ± 7.5 to 35.2 ± 6.7 kg (p = 0.006), 1.16 ± 0.21 to 1.35 ± 0.23 m/s (p = 0.004), and 12.5 ± 4.0 to 9.6 ± 1.7s (p = 0.02). The intervention was feasible and acceptable, and holds promise in promoting weight loss with a concomitant improvement in physical function in older adults.

Roux-en-Y Gastric Bypass in Patients >60 Years of Age: Morbidity and Short-Term Outcomes

BACKGROUND

Obesity is a common disease in the elderly population, and bariatric surgery is the most effective intervention to achieve significant and sustainable weight loss. Many bariatric programs have established an arbitrary cutoff at the age of 60 to 65 years. The aim of this study was to evaluate the safety and short-term outcomes of Roux-en-Y gastric bypass (RYGB) in patients older than 60 years.

PATIENTS AND METHODS

We conducted a retrospective cohort study of patients who underwent RYGB from 2004 to 2019 in a single center. Logistic and linear multivariate regressions were made to compare complications and short-term outcomes between patients aged > 60 years and < 60 years. The statistical significance was set at p ≤ 0.05.

RESULTS

From 849 patients who underwent a primary RYGB, 57 were > 60 years of age. Overall, early and late complications were similar in both groups, except for unexpected intensive care unit (ICU) admission which was more frequent in the > 60 years group. Excess body weight loss (%EWL) and percentage total weight loss (%TWL) at 1 year in patients > 60 years old were 76.6 ± 21.8% and 30.73 ± 6.8%, respectively. Figures for the same parameters in the control group were 81.7 ± 19.9% (p = 0.09) and 34.3 ± 7.2 (p = 0.001), respectively.

CONCLUSIONS

In our experience, an age > 60 is not related to higher rates of overall early and late complications after RYGB. Comorbidity remission rates are similar to those in younger patients. Elderly patients had lower total weight loss at 1 year, but the %EWL was similar in both groups.

The Optimal Nutritional Programme for Bariatric and Metabolic Surgery

PURPOSE OF REVIEW

Bariatric surgery is the most effective treatment for severe and complex obesity; however, the risk of developing nutrient deficiencies varies based upon the type of surgery, degree of malabsorption, and level of nutrition intervention. There are numerous factors that can impact the nutrition status of a patient during their pre- and postoperative journey. We review the critical components and considerations needed in order to provide optimal nutrition care for patients with bariatric surgery.

RECENT FINDINGS

A dietitian, specializing in bariatric surgery, is the best equipped healthcare provider to prepare and support patients in achieving and maintaining optimal nutrition status. We present best practices for both the pre- and postoperative nutrition-related phases of a patient's journey. The dietitian specialist is integral in the assessment and ongoing nutrition care of patients with bariatric surgery. Further consideration should be given to enable access for lifelong follow-up and monitoring.

Differential effects of sodium-glucose cotransporter 2 inhibitor and low-carbohydrate diet on body composition and metabolic profile in obese diabetic db/db mice

INTRODUCTION

Treatment using sodium-glucose cotransporter (SGLT) 2 inhibitor and low-carbohydrate diet (LCD) for obesity and type 2 diabetes are similar in terms of carbohydrate limitation. However, their mechanisms of action differ, and the effects on the body remain unclear. We investigated the effects of SGLT2 inhibitor and LCD on body composition and metabolic profile using the db/db mouse model for obesity and type 2 diabetes.

RESEARCH DESIGN AND METHODS

Eight-week-old male db/db mice were divided into four groups: mice receiving normal diet and vehicle or canagliflozin (Cana) administration and mice receiving LCD and vehicle or Cana administration for 8 weeks. Consumed calories were adjusted to be equal among the groups.

RESULTS

Both Cana administration and LCD feeding resulted in significant weight gain. Cana administration significantly decreased plasma glucose levels and increased plasma insulin levels with preservation of pancreatic β cells. However, LCD feeding did not improve plasma glucose levels but deteriorated insulin sensitivity. LCD feeding significantly reduced liver weight and hepatic triglyceride content; these effects were not observed with Cana administration. Combined treatment with LCD did not lead to an additive increase in blood β-ketone levels.

CONCLUSIONS

SGLT2 inhibitors and LCD exert differential effects on the body. Their combined use may achieve better metabolic improvements in obesity and type 2 diabetes.

Identification of common cardiometabolic alterations and deregulated pathways in mouse and pig models of aging

Aging is the main risk factor for cardiovascular and metabolic diseases, which have become a global concern as the world population ages. These diseases and the aging process are exacerbated in Hutchinson–Gilford progeria syndrome (HGPS or progeria). Here, we evaluated the cardiometabolic disease in animal models of premature and normal aging with the aim of identifying alterations that are shared or specific to each condition. Despite differences in body composition and metabolic markers, prematurely and normally aging mice developed heart failure and similar cardiac electrical abnormalities. High‐throughput proteomics of the hearts of progeric and normally aged mice revealed altered protein oxidation and glycation, as well as dysregulated pathways regulating energy metabolism, proteostasis, gene expression, and cardiac muscle contraction. These results were corroborated in the hearts of progeric pigs, underscoring the translational potential of our findings, which could help in the design of strategies to prevent or slow age‐related cardiometabolic disease.

Dietary weight-loss interventions for the management of obesity in older adults

The obesity epidemic has reached old age in most industrialized countries, but trials elucidating the benefits and risks of weight reduction in older adults above 70 years of age with obesity remain scarce. While some findings demonstrate a reduced risk of mortality and other negative health outcomes in older individuals with overweight and mild obesity (i.e. body mass index (BMI) < 35 kg/m²), other recent research indicates that voluntary weight loss can positively affect diverse health outcomes in older individuals with overweight and obesity (BMI > 27 kg/m²), especially when combined with exercise. However, in this age group weight reduction is usually associated with a reduction of muscle mass and bone mineral density. Since uncertainty persists as to which level overweight or obesity might be tolerable (or even beneficial) for older persons, current recommendations are to consider weight reducing diets only for older persons that are obese (BMI ≥ 30 kg/m²) and have weight-related health problems. Precise treatment modalities (e.g. appropriate level of caloric restriction and indicated dietary composition, such as specific dietary patterns or optimal protein content) as well as the most effective and safest way of adding exercise are still under research. Moreover, the long-term effects of weight-reducing interventions in older individuals remain to be clarified, and dietary concepts that work for older adults who are unable or unwilling to exercise are required. In conclusion, further research is needed to elucidate which interventions are effective in reducing obesity-related health risks in older adults without causing relevant harm in this vulnerable population.

Pathogenesis and clinical management of obesity-related knee osteoarthritis: Impact of mechanical loading

Obesity-related osteoarthritis (OA) is a complex, multifactorial condition that can cause significant impact on patients' quality of life. Whilst chronic inflammation, adipocytokines and metabolic factors are considered to be important pathogenic factors in obesity related OA, there has been limited investigation into the biomechanical impact of obesity on OA development. This review aims to demonstrate that mechanical factors are the major pathological cause of obesity-related OA. The effect of obesity on pathological changes to the osteochondral unit and surrounding connective tissues in OA is summarized, as well as the impact of obesity-related excessive and abnormal joint loading, concomitant joint malalignment and muscle weakness. An integrated therapeutic strategy based on this multi-factorial presentation is presented, to assist in the management of obesity related OA.

THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE

Despite the high prevalence of obesity-related OA, there is no specific guideline available for obesity-related OA management. In this review, we demonstrated the pathological changes of obesity-related OA and summarized the impact of biomechanical factors by proposing a hypothetical model of obesity-related OA change. Therapeutic strategies based on adjusting abnormal mechanical effects are presented to assist in the management of obesity-related OA.

Exploiting common aspects of obesity and cancer cachexia for future therapeutic strategies

Obesity and cancer cachexia are diseases at opposite ends of the BMI. However, despite the apparent dichotomy, these pathologies share some common underlying mechanisms that lead to profound metabolic perturbations. Insulin resistance, adipose tissue lipolysis, skeletal muscle atrophy and systemic inflammation are key players in both diseases. Several strategies for pharmacological treatments have been employed in obesity and cancer cachexia but demonstrated only limited effects. Therefore, there is still a need to develop novel, more effective strategies. In this review we summarize existing therapies and discuss potential novel strategies that could arise by bridging common aspects between obesity and cachexia. We discuss the potential role of macrophage manipulation and the modulation of inflammation by targeting Nuclear Receptors (NRs) as potential novel therapeutic strategies.

Effect of Angiotensin System Inhibitors on Physical Performance in Older People - A Systematic Review and Meta-Analysis

Objective

Preclinical and observational data suggest that angiotensin converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARBs) may be able to improve physical performance in older people via direct and indirect effects on skeletal muscle. We aimed to summarize current evidence from randomised controlled trials in this area.

Design

Systematic review and meta-analysis.

Setting and Participants

Randomized controlled trials enrolling older people, comparing ACEi or ARB to placebo, usual care or another antihypertensive agent, with outcome data on measures of physical performance.

Methods

We searched multiple electronic databases without language restriction between inception and the end of February 2020. Trials were excluded if the mean age of participants was <65 years or treatment was targeting specific diseases known to affect muscle function (for example heart failure). Data were sought on measures of endurance and strength. Standardized mean difference (SMD) treatment effects were calculated using random-effects models with RevMan software.

Results

Eight trials (952 participants) were included. Six trials tested ACEi, 2 trials tested ARBs. The mean age of participants ranged from 66 to 79 years, and the duration of treatment ranged from 2 months to 1 year. Trials recruited healthy older people and people with functional impairment; no trials specifically targeted older people with sarcopenia. Risk of bias for all trials was low to moderate. No significant effect was seen on endurance outcomes [6 trials, SMD 0.04 (95% CI –0.22 to 0.29); P = .77; I² = 53%], strength outcomes [6 trials, SMD –0.02 (95% CI –0.18 to 0.14), P = .83, I² = 21%] or the short physical performance battery [3 trials, SMD –0.04 (95% CI –0.19 to 0.11), P = .60, I² = 0%]. No evidence of publication bias was evident on inspection of funnel plots.

Conclusions and Implications

Existing evidence does not support the use of ACE inhibitors or angiotensin receptor blockers as a single intervention to improve physical performance in older people.

Respiratory Muscle Strengths and Their Association with Lean Mass and Handgrip Strengths in Older Institutionalized Individuals

The study of reduced respiratory muscle strengths in relation to the loss of muscular function associated with ageing is of great interest in the study of sarcopenia in older institutionalized individuals. The present study assesses the association between respiratory muscle parameters and skeletal mass content and strength, and analyzes associations with blood cell counts and biochemical parameters related to protein, lipid, glucose and ion profiles. A multicenter cross-sectional study was performed among patients institutionalized in nursing homes. The respiratory muscle function was evaluated by peak expiratory flow, maximal respiratory pressures and spirometry parameters, and skeletal mass function and lean mass content with handgrip strength, walking speed and bioimpedance, respectively. The prevalence of reduced respiratory muscle strength in the sample ranged from 37.9% to 80.7%. Peak expiratory flow significantly (p < 0.05) correlated to handgrip strength and gait speed, as well as maximal inspiratory pressure (p < 0.01). Maximal expiratory pressure significantly (p < 0.01) correlated to handgrip strength. No correlation was obtained with muscle mass in any of parameters related to reduced respiratory muscle strength. The most significant associations within the blood biochemical parameters were observed for some protein and lipid biomarkers e.g., glutamate-oxaloacetate transaminase (GOT), urea, triglycerides and cholesterol. Respiratory function muscle parameters, peak expiratory flow and maximal respiratory pressures were correlated with reduced strength and functional impairment but not with lean mass content. We identified for the first time a relationship between peak expiratory flow (PEF) values and GOT and urea concentrations in blood which deserves future investigations in order to manage these parameters as a possible biomarkers of reduced respiratory muscle strength.

Sarcopenic Obesity and Activities of Daily Living in Stroke Rehabilitation Patients: A Cross-Sectional Study

Reports investigating the relationship between sarcopenic obesity and activities of daily living in older patients with stroke were limited. This study aimed to examine the prevalence of sarcopenic obesity and its association with activities of daily living in older post-stroke patients in convalescent rehabilitation wards. This study was performed in older post-stroke patients admitted to convalescent rehabilitation wards between January 2017 and March 2019. Sarcopenia was diagnosed based on the skeletal muscle mass index and hand grip strength according to the criteria of the 2019 Asian Working Group for Sarcopenia. Obesity was diagnosed according to the body fat percentage; ≥27% in men, ≥38% in women. The primary outcome was the Functional Independence Measure (FIM) score upon admission, which was analyzed using multiple linear regression. In total, 376 participants (women 44%; mean age 77.5 years) were analyzed and classified as normal (22%), simple obesity (17%), sarcopenia without obesity (32%), and sarcopenic obesity (28%). The presence of sarcopenic obesity was independently associated with the FIM score (95% CI, -16.157 to -5.353), whereas simple obesity and sarcopenia without obesity were not. In conclusion, sarcopenic obesity was independently associated with lower activities of daily living capability in older patients with stroke.

Weight change and risk of the foundation of National Institute of Health Sarcopenia-defined low lean mass: Data from the National Health and Nutrition examination surveys 1999-2004

BACKGROUND

Self-reported weight change may lead to adverse outcomes. We evaluated weight change with cutpoints of low lean mass (LLM) in older adults.

METHODS

Of 4984 subjects ≥60 years from NHANES 1999-2004, we applied LLM cutoffs of appendicular lean mass (ALM):body mass index (BMI) males<0.789, females<0.512. Self-reported weight was assessed at time of survey, and questions asked participants their weight one and 10 years earlier, and at age 25. Weight changes were categorized as greater/less/none than 5%. Logistic regression assessed weight change (gain, loss, no change) on LLM, after adjustment.

RESULTS

Of 4984 participants (56.5% female), mean age and BMI were 71.1 years and 28.2 kg/m2. Mean ALM was 19.7 kg. In those with LLM, 13.5% and 16.3% gained/lost weight in the past year, while 48.9% and 19.4% gained/lost weight in the past decade. Compared to weight at age 25, 85.2 and 6.1% of LLM participants gained and lost ≥5% of their weight, respectively. Weight gain over the past year was associated with a higher risk of LLM (OR 1.35 [0.99,1.87]) compared to weight loss ≥5% over the past year (0.89 [0.70,1.12]). Weight gain (≥5%) over 10-years was associated with a higher risk of LLM (OR 2.03 [1.66, 2.49]) while weight loss (≥5%) was associated with a lower risk (OR 0.98 [0.76,1.28]). Results were robust compared to weight at 25 years (gain OR 2.37 [1.76,3.20]; loss OR 0.95 [0.65,1.39]).

CONCLUSION

Self-reported weight gain suggests an increased risk of LLM. Future studies need to verify the relationship with physical function.

Dietary citrus and/or its extracts intake contributed to weight control: Evidence from a systematic review and meta-analysis of 13 randomized clinical trials

Randomized controlled trials, being published in English and investigating the associations of at least 4 weeks intervention of citrus and/or its extracts on weight loss among adults, were searched from PubMed, Web of Science, Scopus, and Cochrane by June 2019 to conduct a meta-analysis. Thirteen articles, including 921 participants, were selected and evaluated by modified Jadad scale. Pooled results by the random-effects model showed that citrus and/or its extracts administration significantly reduced 1.280 kg body weight (95% CI: -1.818 to -0.741, p = 0.000, I2 = 81.4%), 0.322 kg/m2 BMI (95% CI: -0.599 to -0.046, p = 0.022, I2 = 87.0%), 2.185 cm WC (95% CI: -3.804 to -0.566, p = 0.008, I2 = 98.3%), and 2.137 cm HC (95% CI: -3.775 to -0.500, p = 0.011, I2 = 96.2%), respectively, but no significantly decreased effects on WHR and body fat were observed. Subgroup analysis deduced the different effects of study location, intervention duration on body weight associated indices. No publication bias was observed. Our meta-analysis supported the beneficial effects of citrus and/or its extracts supplement on body weight control, and future well-designed studies are required to firmly establish the clinical efficacy of citrus and/or its extracts intervention on body weight.

Muscle, Bone, and Fat Crosstalk: the Biological Role of Myokines, Osteokines, and Adipokines

PURPOSE OF REVIEW

Skeletal muscle and bone are connected anatomically and physiologically, and play a crucial role in human locomotion and metabolism. Historically, the coupling between muscle and bone has been viewed in light of mechanotransduction, which dictates that the mechanical forces applied to muscle are transmitted to the skeleton to initiate bone formation. However, these organs also communicate through the endocrine system, orchestrated by a family of cytokines namely myokines (derived from myocytes) and osteokines (derived from bone cells). A third player in this biochemical crosstalk is adipose tissue and the secretion of adipokines (derived from adipocytes). In this review, we discuss the bidirectional effects of myokines and osteokines on muscle and bone metabolism, and the impact of adipokines on both of these secretory organs.

RECENT FINDINGS

Several myokines, notably, IL6, irisin, IGF-1, BDNF, myostatin, and FGF2 exert anabolic/catabolic effects on bone, while the osteokines osteocalcin and sclerostin have shown to induce muscle anabolism and catabolism, respectively. Adipokines, such as leptin, resistin, adiponectin, and TNFα (released from adipose tissue), can also modulate muscle and bone metabolism. Contrarily, exercise-mediated release of lipolytic myokines (IL6, irisin, and LIF) stimulates thermogenesis by promoting the browning of adipocytes. Myokines, osteokines, and adipokines exert autocrine/paracrine effects locally as well as through the endocrine system, to regulate muscle, bone, and fat metabolism. Reductions in physical activity and increases in energy intake, both linked with aging, leads to adipocyte hypertrophy and the recruitment of immunological cells (macrophages). In turn, this releases pro-inflammatory adipokines which induces chronic low-grade inflammation (LGI), a key player in the pathology of several diseases. However, exercise-induced stimulation of bioactive cytokines, through muscle-bone-fat crosstalk, increases muscle anabolism, bone formation, mitochondrial biogenesis, glucose utilization, and fatty acid oxidation, and attenuates chronic LGI.

The Role of Imaging Biomarkers in the Assessment of Sarcopenia

BACKGROUND

The diagnosis of sarcopenia through clinical assessment has some limitations. The literature advises studies that include objective markers along with clinical assessment in order to improve the sensitivity and specificity of current diagnostic criteria. The decrease of muscle quality precedes the loss of quantity, so we studied the role magnetic resonance imaging biomarkers as indicators of the quantity and quality of muscle in sarcopenia patients.

METHODS

a cross-sectional analysis was performed to analyze what MR-derived imaging parameters correlate better with sarcopenia diagnostic criteria in women of 70 years of age and over (independent walking and community-dwelling women who were sarcopenic in accordance with EWGSOP criteria with muscle mass adjusted to Spanish population were chosen).

RESULTS

The study included 26 women; 81 ± 8 years old. A strong correlation was obtained between cineanthropometric variables (BMI; thigh perimeter and fat mass) and imaging biomarkers (muscle/fat ratio, fatty infiltration, muscle T2*, water diffusion coefficient, and proton density fat fraction) with coefficients around 0.7 (absolute value).

CONCLUSIONS

Knowing the correlation of clinical parameters and imaging-derived muscle quality indicators can help to identify older women at risk of developing sarcopenia at an early stage. This may allow taking preventive actions to decrease disability, morbidity, and mortality in sarcopenia patients.

Impact of Protein Intake in Older Adults with Sarcopenia and Obesity: A Gut Microbiota Perspective

The continuous population increase of older adults with metabolic diseases may contribute to increased prevalence of sarcopenia and obesity and requires advocacy of optimal nutrition treatments to combat their deleterious outcomes. Sarcopenic obesity, characterized by age-induced skeletal-muscle atrophy and increased adiposity, may accelerate functional decline and increase the risk of disability and mortality. In this review, we explore the influence of dietary protein on the gut microbiome and its impact on sarcopenia and obesity. Given the associations between red meat proteins and altered gut microbiota, a combination of plant and animal-based proteins are deemed favorable for gut microbiota eubiosis and muscle-protein synthesis. Additionally, high-protein diets with elevated essential amino-acid concentrations, alongside increased dietary fiber intake, may promote gut microbiota eubiosis, given the metabolic effects derived from short-chain fatty-acid and branched-chain fatty-acid production. In conclusion, a greater abundance of specific gut bacteria associated with increased satiation, protein synthesis, and overall metabolic health may be driven by protein and fiber consumption. This could counteract the development of sarcopenia and obesity and, therefore, represent a novel approach for dietary recommendations based on the gut microbiota profile. However, more human trials utilizing advanced metabolomic techniques to investigate the microbiome and its relationship with macronutrient intake, especially protein, are warranted.

Sex-Specific Energy Intakes and Physical Activity Levels According to the Presence of Metabolic Syndrome in Korean Elderly People: Korean National Health and Nutrition Examination Survey 2016-2018

This study aimed to analyze the differences in energy intake and physical activity (PA) levels according to sex and the presence of metabolic syndrome (MetS) among elderly people in Korea. Data of 3720 elderly people (aged >65 years) were obtained from the Korean National Health and Nutrition Examination Survey (2016–2018). We analyzed PA levels (occupational and recreational PA) and energy intakes (carbohydrate, protein, and fat). The MetS group showed lower levels of moderate intensity recreational PA and place movement than the non-MetS group (p < 0.05); in the MetS group, PA levels were significantly lower in women than in men (p < 0.05). The intakes of total energy, carbohydrate, fat, and protein were lower in the MetS group than in the non-MetS group (p < 0.001). Both the non-MetS and MetS groups showed lower energy intakes in women than men (p < 0.001). Our study shows that elderly people, especially women, with MetS have significantly lower total PA levels and total energy intakes. We confirmed the importance of increased PA and proper nutritional intake in elderly people. Therefore, it is believed that practical measures such as nutrition education and nutrition guidance and PA education are urgently needed to reduce the incidence of MetS among the elderly.

Both ghrelin deletion and unacylated ghrelin overexpression preserve muscles in aging mice

Sarcopenia, the decline in muscle mass and functionality during aging, might arise from age-associated endocrine dysfunction. Ghrelin is a hormone circulating in both acylated (AG) and unacylated (UnAG) forms with anti-atrophic activity on skeletal muscle. Here, we show that not only lifelong overexpression of UnAG (Tg) in mice, but also the deletion of ghrelin gene (Ghrl KO) attenuated the age-associated muscle atrophy and functionality decline, as well as systemic inflammation. Yet, the aging of Tg and Ghrl KO mice occurs with different dynamics: while old Tg mice seem to preserve the characteristics of young animals, Ghrl KO mice features deteriorate with aging. However, young Ghrl KO mice show more favorable traits compared to WT animals that result, on the whole, in better performances in aged Ghrl KO animals. Treatment with pharmacological doses of UnAG improved muscle performance in old mice without modifying the feeding behavior, body weight, and adipose tissue mass. The antiatrophic effect on muscle mass did not correlate with modifications of protein catabolism. However, UnAG treatment induced a strong shift towards oxidative metabolism in muscle. Altogether, these data confirmed and expanded some of the previously reported findings and advocate for the design of UnAG analogs to treat sarcopenia.

Sarcopenic obesity: Myokines as potential diagnostic biomarkers and therapeutic targets?

Sarcopenic obesity (SO) is a condition characterized by the occurrence of both sarcopenia and obesity and imposes a heavy burden on the health of the elderly. Controversies and challenges regarding the definition, diagnosis and treatment of SO still remain because of its complex pathogenesis and limitations. Over the past few decades, numerous studies have revealed that myokines secreted from skeletal muscle play significant roles in the regulation of muscle mass and function as well as metabolic homeostasis. Abnormalities in myokines may trigger and promote the pathogenesis underlying age-related and metabolic diseases, including obesity, sarcopenia, type 2 diabetes (T2D), and SO. This review mainly focuses on the role of myokines as potential biomarkers for the early diagnosis and therapeutic targets in SO.