Sarcopenic obesity: how do we treat it?

Association Between Reduced Daily Steps and Sarcopenic Obesity in Treatment-Seeking Adults With Obesity

Objectives: Understanding the condition that describes the coexistence of obesity and sarcopenia, termed sarcopenic obesity (SO), is becoming a scientific and clinical priority. In this study, we aimed to assess the prevalence of SO in treatment-seeking adults with obesity and investigate any potential association between SO and a sedentary lifestyle, expressed in terms of daily steps. Methods: In this cross-sectional, prospective observational study, body composition and daily steps measurements were obtained using a segmental body composition analyser (Tanita BC-418) and an Omron HJ-320 pedometer, respectively, in 111 adults of both genders with obesity (body mass index; BMI ≥ 30 kg/m²), referred to the Outpatient Clinic in the Department of Nutrition and Dietetics at Beirut Arab University (BAU) in Lebanon. The participants were then categorized according to the presence of absence of SO, defined as an appendicular lean mass divided by body weight (ALM/weight) × 100%) of less than 23.40 and 29.60 in females and males, respectively. Results: Fifty-five of the 111 participants with obesity, with a mean age of 39.62 ± 16.55 years and a mean BMI of 38.05 ± 5.33 kg/m² met the criteria for SO and displayed a significantly higher prevalence of inactivity (<5,000 daily steps), i.e., nearly double (54.5% vs. 32.1%; p = 0.017) and they had a lower mean number of daily steps than those in the group without SO (5,279 ± 2,641 vs. 6,732 ± 2,989; p = 0.008). Linear regression analysis showed that SO is associated with a lower number of daily steps by 1,421 (β = -1421.4; -2508.9, -333.9; p = 0.011) after adjusting for age, gender employment and the presence of cardiometabolic disease. Conclusion: Sarcopenic obesity affects nearly 50% of treatment-seeking adults with obesity. Moreover, it seems to be associated with a lower number of daily steps and a sedentary lifestyle. Future studies are needed to clarify whether this may influence clinical outcomes. If this is shown to be the case, weight management programmes should incorporate additional physical activity strategies in this population.

Understanding Sarcopenic Obesity in Terms of Definition and Health Consequences: A Clinical Review

BACKGROUND AND AIM

Research interests in a new phenotype termed as sarcopenic obesity (SO), which refers to a decrease in lean body mass and muscle strength associated with an increase in body fat deposition, have grown. However, neither SO definition nor its impact on health outcomes is clear. In the current paper, we aim to summarize the available literature on the dilemma surrounding the definition of SO, and the potential health consequences of this phenomenon on individuals with overweight and obesity.

METHODS

A literature review using the PubMed/Medline database was conducted and data were summarized by applying a narrative approach, based on clinical expertise in the interpretation of the available evidence base in the literature.

RESULTS

Some definitions that account for body mass (i.e., body weight, body mass index) seem to be more suitable for screening of SO and revealed as clinically useful. The association between SO and certain health outcomes has also been investigated, especially those related to obesity; however, little is known about the association of SO with psychosocial distress and health-related quality of life impairment, as well as harsh outcomes such as mortality.

CONCLUSION

International consensus regarding SO definition is needed, which would allow for a better understanding of its prevalence. Moreover, future investigations should be conducted in order to determine whether SO has an adverse effect (i.e., cause-effect relationship, in addition to association) on health. Once these issues are achieved, confirmed and clarified, evidenced-based protocols of treatment may become necessary to address the increase in the prevalence of obesity and sarcopenia worldwide.

Diagnosis of pre-sarcopenia from a single selectional crosscut at C3 region, using CT scans before radiotherapy

Introduction

Purpose: the main purpose of this study was to diagnose pre-sarcopenia in cancer patients who had lack of computed tomography (CT) abdominal images, with a newly discovered method based on cervical images. Material and methods: a sample of 37 patients with either lung cancer or a cancer that affected the upper digestive system underwent radiotherapy computed simulation which included measurements at C3 and L3 regions. Skeletal muscle mass (SMM) and skeletal muscle index (SMI) were determined by Hounsfield units and compared in both regions. Pre-sarcopenia was identified according to the cut-points currently established: ≤ 41 cm2/m2 in females, ≤ 43 cm2/m2 in males with a BMI ≤ 25 kg/m2, and ≤ 53 cm2/m2 in males with a BMI > 25 kg/m2. Results: the correlation of SMM and SMI between the C3 and L3 regions was R2 = 0.876 and R2 = 0.805, respectively. Moreover, there was a positive association (86.49%) in terms of the diagnosis of pre-sarcopenia according to both regions. In total, eleven pre-sarcopenic patients (29.37%) were identified; three of them being overweight (27.27%) and two of them being obese (18.18%). Conclusion: a single sectional cross at the level of C3 can be used for the diagnosis of pre-sarcopenia. This new method avoids unnecessary irradiation, saves hospital costs and detects malnutrition before starting radiotherapy treatment in cancer patients who have lack of CT abdominal imaging.

Association between sarcopenic obesity and higher risk of type 2 diabetes in adults: A systematic review and meta-analysis

BACKGROUND

The coexistence of sarcopenia and obesity is referred to as sarcopenic obesity (SO) and it has been hypothesized that the two components of SO may synergistically increase their negative effects. However, many uncertainties still surround this condition especially with regard to its potential negative effects on health outcomes.

AIM

To conduct a systematic review to determine the prevalence of sarcopenia among adults with overweight and obesity and to investigate whether SO was associated with a higher risk of type 2 diabetes (T2D).

METHODS

This study was conducted in adherence with the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Literature searches, study selection, methodology development and quality appraisal were performed independently by two authors and the data were collated by means of meta-analysis and narrative synthesis.

RESULTS

Of the 606 articles retrieved, 11 studies that comprised a total of 60118 adults with overweight and obesity of both genders met the inclusion criteria and were reviewed, revealing two main findings. First, the overall prevalence of sarcopenia is 43% in females and 42% in males who are with overweight and obesity. Secondly, the presence of SO increases the risk of T2D by 38% with respect to those without SO (OR = 1.38, 95%CI: 1.27-1.50).

CONCLUSION

A high prevalence of sarcopenia has been found among adults with overweight and obesity regardless of their gender and this condition seems to be associated with a higher risk of T2D. Clinician should be aware of this scenario in their clinical practice for the better management of both obesity and T2D.

Sarcopenic obesity in fatty liver

PURPOSE OF REVIEW

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steato hepatitis have an increasing prevalence among liver diseases. Overweight and obesity are frequently associated conditions in patients with fatty liver. Skeletal muscle mass depletion may also coexist with chronic liver disease even in obese patients. This review will focus on the relationship between sarcopenic obesity and fatty liver.

RECENT FINDINGS

Obesity and sarcopenia are frequently encountered in patients with NAFLD. Adipose tissue is able to release molecules (adipokines) that regulate lipid metabolism, interact with insulin sensitivity and may contribute to induce fibrogenesis in the liver. Skeletal muscle tissue is able to secrete myokines regulating muscle metabolism and insulin sensitivity. Myokines perturbation has been reported to influence adipose tissue mass and fat deposition in the liver. Sarcopenia has been reported as independent risk factor for the development of NAFLD, and for a more severe liver fibrosis in patients with NAFLD.

SUMMARY

The interaction between skeletal muscle, adipose tissue and the liver may play a role in the development of NAFLD. Sarcopenia and sarcopenic obesity are risk factors for the development of fatty liver and associated with more severe liver fibrosis. Management is not standardized, but dietary counseling and physical training have been proposed as promising strategies. Bariatric surgery may be considered in patients with severe 'resistant' obesity.

Optimal Protein Intake during Weight Loss Interventions in Older Adults with Obesity

Obesity rates in people 60 years and older are increasing. While obesity is linked with detrimental health risks, weight loss in this population has previously been considered controversial due to potential worsening of age-related sarcopenia. Protein intake during energy restriction has been linked to lean body mass preservation. No formal guidelines for optimal protein intake during structured weight loss interventions exist for this population, but it appears that the current Recommended Dietary Allowance of 0.8 grams per kilogram of body weight per day may be inadequate. The purpose of this review is to discuss optimal protein intake during structured weight loss interventions in persons 60 years and older with obesity and to present a framework for guidelines to be used by health professionals focusing on weight loss interventions in older adults. Goals for the amount, source, and timing of protein intake, from both food and supplements, are presented and discussed.

Mechanisms Underlying Metabolic Syndrome-Related Sarcopenia and Possible Therapeutic Measures

Although there are several reviews that report the interrelationship between sarcopenia and obesity and insulin resistance, the relation between sarcopenia and the other signs that compose the metabolic syndrome (MetS) has not been extensively revised. Here, we review the mechanisms underlying MetS-related sarcopenia and discuss the possible therapeutic measures proposed. A vicious cycle between the loss of muscle and the accumulation of intramuscular fat might be associated with MetS via a complex interplay of factors including nutritional intake, physical activity, body fat, oxidative stress, proinflammatory cytokines, insulin resistance, hormonal changes, and mitochondrial dysfunction. The enormous differences in lipid storage capacities between the two genders and elevated amounts of endogenous fat having lipotoxic effects that lead to the loss of muscle mass are discussed. The important repercussions of MetS-related sarcopenia on other illnesses that lead to increased disability, morbidity, and mortality are also addressed. Additional research is needed to better understand the pathophysiology of MetS-related sarcopenia and its consequences. Although there is currently no consensus on the treatment, lifestyle changes including diet and power exercise seem to be the best options.

Fluctuations in dietary intake during treatment for childhood leukemia: A report from the DALLT cohort

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. Nutritional morbidities are a persistent problem facing pediatric patients during and after treatment and age-gender groups that are at risk for nutritional conditions have not been clearly identified. Therapy is a contributing factor; however, the role of dietary intake remains largely unknown. Prior to conduct of interventional trials, an understanding of the effects of treatment on fluctuations in dietary intake is necessary.

METHODS

We enrolled 794 children with ALL in a prospective clinical trial. Dietary intake was collected with a food frequency questionnaire at diagnosis and throughout the course of treatment for pediatric ALL. Reported values were compared to the Dietary Recommended Intake (DRI), and normative values (NHANES). Hierarchical linear models and multilevel mixed-effects ordered logistic regression models were used to evaluate longitudinal changes in dietary intake; independent samples t-test with Bonferroni correction was performed to compare to NHANES.

RESULTS

Of the evaluable participants at each timepoint, dietary intake was obtained on 81% (n = 640), 74% (n = 580) and 74% (n = 558) at diagnosis, end of induction phase of treatment, and continuation, respectively. Despite exposure to corticosteroids, caloric intake decreased over therapy for most age-gender groups. Predictive models of excess intake found reduced odds of over-consuming calories (OR 0.738, P < 0.05); however, increased odds of over-consuming fat (OR 6.971, P < 0.001). When compared to NHANES, we consistently found that ≥1/3 of children were consuming calories in excess of normative values. For select micronutrients, a small proportion of participants were above or below the DRI at each time evaluated.

CONCLUSIONS

Our study suggests that dietary intake fluctuates during treatment for ALL as compared to age-gender recommended and normative values. Improving our understanding of nutrient fluctuations and dietary quality will facilitate subsequent analyses addressing relationships of dietary intake, toxicity, and survival.

Sodium-glucose cotransporter 2 inhibitor-induced changes in body composition and simultaneous changes in metabolic profile: 52-week prospective LIGHT (Luseogliflozin: the Components of Weight Loss in Japanese Patients with Type 2 Diabetes Mellitus) Study

AIMS/INTRODUCTION

It is unclear how changes in body composition induced by sodium-glucose cotransporter 2 (SGLT2) inhibitor treatment correlate with metabolic profile changes. We aimed to clarify how metabolic profile changes correlate with body component changes, and if SGLT2 inhibitor treatment causes sarcopenia and bone mineral content (BMC) loss.

MATERIALS AND METHODS

Moderately obese Japanese type 2 diabetes patients, treated with luseogliflozin for a year, were observed prospectively and evaluated for body composition changes. We analyzed the changes in the individual body components during treatment, and their correlation with other clinical variables.

RESULTS

The efficacy analysis set comprised 37 of 43 enrolled patients. The total fat mass significantly decreased early in the treatment at and after week 4, with a mean decrease of -1.97 kg (95% confidence interval -2.66 to -1.28) at week 24. The visceral fat area at week 24 showed an average downward trend, although this was not significant. The changes in visceral fat area in individual patients showed a significant negative correlation with the extent of the baseline visceral fat area (r = -0.399, P = 0.023). The skeletal muscle mass index showed a significant but small change at and after week 36. The BMC profile showed a transient significant decrease only at week 12. No significant change in BMC was noted at other time-points.

CONCLUSIONS

Luseogliflozin treatment brought about favorable changes in body composition and metabolism of moderately obese Japanese type 2 diabetes patients, accompanied by body fat reduction, and minimal muscle and BMC reduction.

Environmental risk factors and nonpharmacological and nonsurgical interventions for obesity: An umbrella review of meta-analyses of cohort studies and randomized controlled trials

BACKGROUND

Multiple environmental factors have been implicated in obesity, and multiple interventions, besides drugs and surgery, have been assessed in obese patients. Results are scattered across many studies and meta-analyses, and they often mix obese and overweight individuals.

MATERIALS AND METHODS

PubMed and Cochrane Database of Systematic Reviews were searched through 21 January 2017 for meta-analyses of cohort studies assessing environmental risk factors for obesity, and randomized controlled trials investigating nonpharmacological and nonsurgical therapeutic interventions for obesity. We excluded data on overweight participants. Evidence from observational studies was graded according to criteria that included the statistical significance of the random-effects summary estimate and of the largest study in a meta-analysis, the number of obesity cases, heterogeneity between studies, 95% prediction intervals, small-study effects and excess significance. The evidence of intervention studies for obesity was assessed with the GRADE framework.

RESULTS

Fifty-four articles met eligibility criteria, including 26 meta-analyses of environmental risk factors (166 studies) and 46 meta-analyses of nondrug, nonsurgical interventions (206 trials). In adults, the only risk factor with convincing evidence was depression, and childhood obesity, adolescent obesity, childhood abuse and short sleep duration had highly suggestive evidence. Infancy weight gain during the first year of life, depression and low maternal education had convincing evidence for association with paediatric obesity. All interventions had low or very-low-quality evidence with one exception of moderate-quality evidence for one comparison (no differences in efficacy between brief lifestyle primary care interventions and other interventions for paediatric obesity). Summary effect sizes were mostly small across compared interventions (maximum 5.1 kg in adults and 1.78 kg in children) and even these estimates may be inflated.

CONCLUSIONS

Depression, obesity in earlier age groups, short sleep duration, childhood abuse and low maternal education have the strongest support among proposed risk factors for obesity. Furthermore, there is no high-quality evidence to recommend treating obesity with a specific nonpharmacological and nonsurgical intervention among many available, and whatever benefits in terms of magnitude of weight loss appear small.

Oxidative muscles have better mitochondrial homeostasis than glycolytic muscles throughout life and maintain mitochondrial function during aging

Preservation of mitochondrial function, which is dependent on mitochondrial homeostasis (biogenesis, dynamics, disposal/recycling), is critical for maintenance of skeletal muscle function. Skeletal muscle performance declines upon aging (sarcopenia) and is accompanied by decreased mitochondrial function in fast-glycolytic muscles. Oxidative metabolism promotes mitochondrial homeostasis, so we investigated whether mitochondrial function is preserved in oxidative muscles. We compared tibialis anterior (predominantly glycolytic) and soleus (oxidative) muscles from young (3 mo) and old (28-29 mo) C57BL/6J mice. Throughout life, the soleus remained more oxidative than the tibialis anterior and expressed higher levels of markers of mitochondrial biogenesis, fission/fusion and autophagy. The respiratory capacity of mitochondria isolated from the tibialis anterior, but not the soleus, declined upon aging. The soleus and tibialis anterior exhibited similar aging-associated changes in mitochondrial biogenesis, fission/fusion, disposal and autophagy marker expression, but opposite changes in fiber composition: the most oxidative fibers declined in the tibialis anterior, while the more glycolytic fibers declined in the soleus. In conclusion, oxidative muscles are protected from mitochondrial aging, probably due to better mitochondrial homeostasis ab initio and aging-associated changes in fiber composition. Exercise training aimed at enriching oxidative fibers may be valuable in preventing mitochondria-related aging and its contribution to sarcopenia.

Association between Sarcopenic Obesity, Type 2 Diabetes, and Hypertension in Overweight and Obese Treatment-Seeking Adult Women

The last decade has seen a new condition that describes the coexistence of obesity and sarcopenia, termed sarcopenic obesity (SO). We aimed to assess the prevalence of SO in overweight and obese treatment-seeking adult women and the association with type 2 diabetes, hypertension, and dyslipidemia. A body composition assessment was conducted with an InBody bioimpedance analyser in 154 overweight and obese women referred to the Outpatient Clinic in the Department of Nutrition and Dietetics at Beirut Arab University (BAU) in Lebanon, and 30 normal-weight participants of similar age. The overweight and obese patients were then categorized as being with or without sarcopenia. Thirty-one out of the 154 overweight or obese participants met the criteria for SO and displayed a significantly higher prevalence of type 2 diabetes and hypertension than those without SO. Logistic regression analysis showed that SO increases the odds of having type 2 diabetes and hypertension by nearly 550% (odds ratio = 5.42, 95% confidence interval = 1.37⁻21.40, p < 0.05) after adjusting for central fat, eating habits, level of physical activity, and smoking. SO affects nearly 20% of treatment-seeking overweight and obese adult women. Moreover, SO seems to be strongly associated with type 2 diabetes and hypertension.

Sarcopenic Obesity: Definition, Health Consequences and Clinical Management

Over the last decade, a new condition, which occurs in the presence of both sarcopenia and obesity, has been termed “sarcopenic obesity”. The term describes the coexistence of obesity, defined as the increase in body fat mass deposition, and sarcopenia, defined as the reduction in lean mass and muscle strength. However, many uncertainties still surround the condition of sarcopenic obesity in terms of its definition, the adverse short- and long-term health effects (i.e., medical disease, psychosocial functioning, quality of life and mortality) and its clinical management. The aim of this short communication is to emphasize some crucial aspects that future research should take into account in order to avoid bias and misinterpretations and to underline that the study of sarcopenic obesity should be considered a scientific and clinical priority, as reported by the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO).

Sarcopenic obesity in cirrhosis-The confluence of 2 prognostic titans

Sarcopenia and obesity are 2 major health conditions with a growing prevalence in cirrhosis. The concordance of these 2 conditions, sarcopenic obesity, is associated with higher rates of mortality and impact on the metabolic profile and physical function than either condition alone. To date, there is little consensus surrounding the diagnostic criteria for sarcopenia, obesity or as a result, sarcopenic obesity in patients with cirrhosis. Cross-sectional imaging, although the most accurate diagnostic technique, has practical limitations for routine use in clinical practice. Management strategies are focused on increasing muscle mass and strength. The present review provides an overview of the diagnosis, pathophysiology, prognostic implications and management strategies available for sarcopenic obesity in cirrhosis. We also discuss the associated condition myosteatosis, the pathological accumulation of fat in skeletal muscle. Much work needs to be done to advance both clinical care and research in this area. Future directions require consensus definitions for sarcopenia, obesity and sarcopenic obesity, an expansion of our understanding of the complex pathogenesis of the muscle-liver-adipose tissue axis in cirrhosis and evidence to support management recommendations for nutrition, exercise and pharmacological therapies.

Physical performance measures in screening for reduced lean body mass in adult females with obesity

BACKGROUND & AIMS

Little is known about the reduction of lean body mass (LBM) in obesity, or how to identify it in standard clinical settings. We therefore aimed to assess the prevalence of low LBM in adult females with obesity, and to identify the reliability of simple tools for its screening in this population.

METHODS AND RESULTS

Dual-energy X-ray absorptiometry (DXA) body composition assessment was used to categorise 147 female participants with obesity as with or without low LBM, according to the new definition that takes into account both appendicular lean mass (ALM) and body mass index (BMI)-ALM/BMI <0.512. Participants were also administered the six-minute walking test, handgrip-strength test and 4-metre gait-speed test. Of the sample of 147 participants, 93 (63.3%) met the criteria for reduced LBM. Stepwise multivariate logistic regression analysis showed that the six-minute walking test was the only independent test associated with low LBM (OR = 0.992, 95%CI 0.987-0.998). Receiver operating characteristic (ROC) curve analysis found that the discriminating cut-off points of the tests considered were 470 m, 3.30 s (gait speed = 1.2 m/sec) and 23.5 kg respectively; the 4-metre gait-speed test seems to provide the best balance of sensitivity and specificity, and the greatest discriminatory power at 90% sensitivity.

CONCLUSIONS

Treatment-seeking adult females with obesity display a great prevalence of reduced LBM. The six-minute walking test was the only independent test associated with low LBM, but the 4-metre gait-speed test seems to be the most accurate functional test for screening for this condition in that population.

Exercise and Nutrition Strategies to Counteract Sarcopenic Obesity

As the population is aging rapidly, there is a strong increase in the number of individuals with chronic disease and physical limitations. The decrease in skeletal muscle mass and function (sarcopenia) and the increase in fat mass (obesity) are important contributors to the development of physical limitations, which aggravates the chronic diseases prognosis. The combination of the two conditions, which is referred to as sarcopenic obesity, amplifies the risk for these negative health outcomes, which demonstrates the importance of preventing or counteracting sarcopenic obesity. One of the main challenges is the preservation of the skeletal muscle mass and function, while simultaneously reducing the fat mass in this population. Exercise and nutrition are two key components in the development, as well as the prevention and treatment of sarcopenic obesity. The main aim of this narrative review is to summarize the different, both separate and combined, exercise and nutrition strategies so as to prevent and/or counteract sarcopenic obesity. This review therefore provides a current update of the various exercise and nutritional strategies to improve the contrasting body composition changes and physical functioning in sarcopenic obese individuals.

Effect of resistance training and protein intake pattern on myofibrillar protein synthesis and proteome kinetics in older men in energy restriction

KEY POINTS

Strategies to enhance the loss of fat while preserving muscle mass during energy restriction are of great importance to prevent sarcopenia in overweight older adults. We show for the first time that the integrated rate of synthesis of numerous individual contractile, cytosolic and mitochondrial skeletal muscle proteins was increased by resistance training (RT) and unaffected by dietary protein intake pattern during energy restriction in free-living, obese older men. We observed a correlation between the synthetic rates of skeletal muscle-derived proteins obtained in serum (creatine kinase M-type, carbonic anhydrase 3) and the synthetic rates of proteins obtained via muscle sampling; and that the synthesis rates of these proteins in serum revealed the stimulatory effects of RT. These results have ramifications for understanding the influence of RT on skeletal muscle and are consistent with the role of RT in maintaining muscle protein synthesis and potentially supporting muscle mass preservation during weight loss.

ABSTRACT

We determined how the pattern of protein intake and resistance training (RT) influenced longer-term (2 weeks) integrated myofibrillar protein synthesis (MyoPS) during energy restriction (ER). MyoPS and proteome kinetics were measured during 2 weeks of ER alone and 2 weeks of ER plus RT (ER + RT) in overweight/obese older men. Participants were randomized to consume dietary protein in a balanced (BAL: 25% daily protein per meal × 4 meals) or skewed (SKEW: 7:17:72:4% daily protein per meal) pattern (n = 10 per group). Participants ingested deuterated water during the consecutive 2-week periods, and skeletal muscle biopsies and serum were obtained at the beginning and conclusion of ER and ER + RT. Bulk MyoPS (i.e. synthesis of the myofibrillar protein sub-fraction) and the synthetic rates of numerous individual skeletal muscle proteins were quantified. Bulk MyoPS was not affected by protein distribution during ER or ER + RT (ER: BAL = 1.24 ± 0.31%/day, SKEW = 1.26 ± 0.37%/day; ER + RT: BAL = 1.64 ± 0.48%/day, SKEW = 1.52 ± 0.66%/day) but was ∼26% higher during ER + RT than during ER (P = 0.023). The synthetic rates of 175 of 190 contractile, cytosolic and mitochondrial skeletal muscle proteins, as well as synthesis of muscle-derived proteins measured in serum, creatine kinase M-type (CK-M) and carbonic anhydrase 3 (CA-3), were higher during ER + RT than during ER (P < 0.05). In addition, the synthetic rates of CK-M and CA-3 measured in serum correlated with the synthetic rates of proteins obtained via muscle sampling (P < 0.05). This study provides novel data on the skeletal muscle adaptations to RT and dietary protein distribution.

Characterization of Ageing- and Diet-Related Swine Models of Sarcopenia and Sarcopenic Obesity

Sarcopenia and sarcopenic obesity are currently considered major global threats for health and well-being. However, there is a lack of adequate preclinical models for their study. The present trial evaluated the suitability of aged swine by determining changes in adiposity, fatty acids composition, antioxidant status and lipid peroxidation, development of metabolic disturbances and structural changes in tissues and organs. Iberian sows with clinical evidence of aging-related sarcopenia were fed a standard diet fulfilling their maintenance requirements or an obesogenic diet for 100 days. Aging and sarcopenia were related to increased lipid accumulation and cellular dysfunction at both adipose tissue and non-adipose ectopic tissues (liver and pancreas). Obesity concomitant to sarcopenia aggravates the condition by increasing visceral adiposity and causing dyslipidemia, insulin resistance and lipotoxicity in non-adipose tissues. These results support that the Iberian swine model represents certain features of sarcopenia and sarcopenic obesity in humans, paving the way for future research on physiopathology of these conditions and possible therapeutic targets.

Obesity phenotypes and their paradoxical association with cardiovascular diseases

The pro-inflammatory state of the visceral adipose tissue (VAT) is supposed to accelerate cardiovascular (CV) and metabolic diseases in obese subjects. Some studies have recently reported an improved CV prognosis in certain obese and overweight patients as compared with leaner ones. This phenomenon, known as the "obesity paradox" (OP), has been described in many chronic diseases. This narrative review is based on the material searched for and obtained via PubMed and Web of Science up to May 2017. The search terms we used were: "obesity, paradox, adipose tissue" in combination with "cardiovascular, coronary heart disease, heart failure, arrhythmias". Using the current Body Mass Index (BMI)-based obesity definition, individuals with different clinical and biochemical characteristics are gathered together in the same category. Emerging evidence point to the existence of many "Obesity phenotypes" with different association with CV risk, accordingly to physical and life-style features. In this narrative review, we discussed if obesity phenotypes may be associated with a different CV risk, potentially explaining the OP. As a globally accepted definition of obesity is still lacking, we emphasized the need of a new approach, which should consider the heterogeneity of obesity. Better defining "obesities" and related CV risk is critical to markedly improve the classical BMI-based definition of obesity.

Free Fatty Acid Receptor 4 Mediates the Beneficial Effects of n-3 Fatty Acids on Body Composition in Mice

As populations continue to age worldwide, sarcopenic obesity has heightened interest due to its medical importance. Although much evidence now indicates that n-3 fatty acids (FAs) may have beneficial effects on body composition including fat and muscle, their exact mechanisms have not yet been elucidated. Because free FA receptor 4 (FFA4) has been reported to be a receptor for n-3 FAs, we hypothesized that the protective role of n-3 FAs on body composition could be mediated by FFA4. To test this possibility, we generated mice overexpressing n-3 FAs but lacking FFA4 by crossing fat-1 transgenic (fat-1 ^Tg+) and FFA4 knockout (Ffar4 ^-/-) mice. Because fat-1 ^Tg+ mice, in which n-6 is endogenously converted into n-3 FAs, contain high n-3 FA levels, they could be a good animal model for studying the effects of n-3 FAs in vivo. Male and female littermates were included in high-fat-diet- (HFD) and ovariectomy-induced models, respectively. In the HFD model, male fat-1 ^Tg+ mice had a lower percentage of fat mass and a higher percentage of lean mass than their wild-type littermates only when they had the Ffar4 ^+/+ not the Ffar4 ^-/- background. Female fat-1 ^Tg+ mice showed less increase of fat mass percentage and less decrease of lean mass percentage after ovariectomy than wild-type littermates. However, these effects on body composition were attenuated in the Ffar4 ^-/- background. Taken together, our results indicate that the beneficial effects of n-3 FAs on body composition were mediated by FFA4 and thus suggest that FFA4 may be a potential therapeutic target for modulating sarcopenic obesity.

Phenotypes of Obesity: How it Impacts Management

PURPOSE OF REVIEW

The worldwide prevalence of obesity is increasing. Obesity is strongly associated with many chronic health conditions that have been shown to improve with weight loss. However, counseling patients on weight loss can be challenging. Identifying specific aspects of weight management may personalize the conversation about weight loss and better address the individual patient's health goals and perceived barriers to change.

RECENT FINDINGS

Physical and behavioral phenotypes are being identified to better tailor treatment recommendations, given lack of efficacy of currently available interventions. The current review provides a summary of the evidence behind the management of several recognized clinical phenotypes, to include body fat distribution (e.g., central obesity), muscle mass (e.g., sarcopenic obesity of the elderly), and problematic eating behaviors (e.g., cravings). Identifying specific aspects of weight management may personalize the conversation about weight loss and better address the individual patient's health goals and perceived barriers to change.

Aerobic or Resistance Exercise, or Both, in Dieting Obese Older Adults

BACKGROUND

Obesity causes frailty in older adults; however, weight loss might accelerate age-related loss of muscle and bone mass and resultant sarcopenia and osteopenia.

METHODS

In this clinical trial involving 160 obese older adults, we evaluated the effectiveness of several exercise modes in reversing frailty and preventing reduction in muscle and bone mass induced by weight loss. Participants were randomly assigned to a weight-management program plus one of three exercise programs - aerobic training, resistance training, or combined aerobic and resistance training - or to a control group (no weight-management or exercise program). The primary outcome was the change in Physical Performance Test score from baseline to 6 months (scores range from 0 to 36 points; higher scores indicate better performance). Secondary outcomes included changes in other frailty measures, body composition, bone mineral density, and physical functions.

RESULTS

A total of 141 participants completed the study. The Physical Performance Test score increased more in the combination group than in the aerobic and resistance groups (27.9 to 33.4 points [21% increase] vs. 29.3 to 33.2 points [14% increase] and 28.8 to 32.7 points [14% increase], respectively; P=0.01 and P=0.02 after Bonferroni correction); the scores increased more in all exercise groups than in the control group (P<0.001 for between-group comparisons). Peak oxygen consumption (milliliters per kilogram of body weight per minute) increased more in the combination and aerobic groups (17.2 to 20.3 [17% increase] and 17.6 to 20.9 [18% increase], respectively) than in the resistance group (17.0 to 18.3 [8% increase]) (P<0.001 for both comparisons). Strength increased more in the combination and resistance groups (272 to 320 kg [18% increase] and 288 to 337 kg [19% increase], respectively) than in the aerobic group (265 to 270 kg [4% increase]) (P<0.001 for both comparisons). Body weight decreased by 9% in all exercise groups but did not change significantly in the control group. Lean mass decreased less in the combination and resistance groups than in the aerobic group (56.5 to 54.8 kg [3% decrease] and 58.1 to 57.1 kg [2% decrease], respectively, vs. 55.0 to 52.3 kg [5% decrease]), as did bone mineral density at the total hip (grams per square centimeter; 1.010 to 0.996 [1% decrease] and 1.047 to 1.041 [0.5% decrease], respectively, vs. 1.018 to 0.991 [3% decrease]) (P<0.05 for all comparisons). Exercise-related adverse events included musculoskeletal injuries.

CONCLUSIONS

Of the methods tested, weight loss plus combined aerobic and resistance exercise was the most effective in improving functional status of obese older adults. (Funded by the National Institutes of Health; LITOE ClinicalTrials.gov number, NCT01065636 .).

Prevalence of obesity, sarcopenic obesity and associated factors: A FIBRA Network study

Abstract Introduction: Sarcopenic obesity in older adults may lead to an inability to use muscles efficiently and has been associated with functional deficits and disabilities. Objective: To identify the prevalence of obesity and sarcopenic obesity (SO) among community-dwelling older adults, and to characterize associated sociodemographics, health conditions and functional performance. Methods: Study data are from the FIBRA Network database of the Federal University of Minas Gerais. There were 1,373 older adult participants, subdivided into three groups: 1) non-obese; 2) non-sarcopenic obese; and 3) sarcopenic obese (SO). The latter is defined as a BMI ≥30 kg/m2 and weak palmar grip strength (PGS). Results: The overall prevalence of obesity and SO among older adults was 25.85% and 4.44%, respectively, with levels of frailty and pre-frailty among at 36.1% and 59%, respectively. Gait speed (GS) was lower in the SO group as well, compared to the other groups. An average increase in GS of 0.1 m/sec reduced the likelihood of SO by 85.1%, in average. Sarcopenic obese older adults were 14.2 times more likely to be pre-fragile and 112.9 times more likely to be fragile than the other groups. Conclusion: The prevalence of obesity found in this study was higher than that in the general population, but similar to national statistics for the sample’s mean age and gender. SO was directly associated with frailty in advanced and instrumental activities of daily living as well as gait speed and significantly increased the likelihood of being pre-frail and frail. GS may be an extremely useful tool for monitoring the progress of SO in older adults.

Body Composition Outcomes of a Qigong Intervention Among Community-Dwelling Aging Adults

Aging causes various changes in body composition, which are critical implications for health and physical functioning in aging adults. The aim of this study was to explore the body composition outcomes of a qigong intervention among community-dwelling aging adults. This was a quasi-experimental study in which 90 participants were recruited. Forty-eight participants (experimental group) attended a 30-min qigong program 3 times per week for 12 weeks, whereas 42 participants (control group) continued performing their usual daily activities. The experimental group achieved a greater reduction in the fat mass percentage at the posttest, and exhibited increased fat-free mass, lean body mass percentage, and lean body mass to fat mass ratio compared with the controls. No difference between the two groups in body mass index, fat mass, and lean body mass was observed. These results indicated that the qigong intervention showed beneficial outcomes of body composition among community-dwelling aging adults.

Effects of a nutrition plus exercise programme on physical function in sarcopenic obese elderly people: study protocol for a randomised controlled trial

INTRODUCTION

With a rapidly ageing population, sarcopenic obesity, defined as decreased muscle mass and function combined with increased body fat, is a complex health problem. Although sarcopenic obesity contributes to a decline in physical function and exacerbates frailty in older adults, evidence from clinical trials about the effect of exercise and nutrition on this complex syndrome in Chinese older adults is lacking.

METHODS AND ANALYSIS

We devised a study protocol for a single-blind randomised controlled trial. Sarcopenia is described as age-related decline in muscle mass plus low muscle strength and/or low physical performance. Obesity is defined as a percentage of body fat above the 60th centile. Ninety-two eligible participants will be randomly assigned to a control group, nutrition group, exercise group and nutrition plus exercise group to receive an 8-week intervention and 12-week follow-up. The primary outcomes will be the change in short physical performance battery scores, grip strength and 6 m usual gait speed. The secondary outcomes will include basic activities of daily living scores, instrumental activity daily living scores, body composition and body anthropometric indexes. For all main analyses, the principle of intention-to-treat will be used.

ETHICS AND DISSEMINATION

This study was approved by the medical ethics committee of Zhejiang Hospital on 25 November 2015. The study will present data targeting the clinical effects of nutrition and exercise on physical function and body composition in a Chinese older population with sarcopenic obesity. The results will help to provide important clinical evidence of the role of complex non-pharmaceutical interventions for sarcopenic obese older people. The findings of this study will be submitted to peer-reviewed medical journals for publication and presented at relevant academic conferences.

TRIAL REGISTRATION NUMBER

ChiCTR-IOR-15007501; Pre-results.

Physical activity and sarcopenic obesity: definition, assessment, prevalence and mechanism

Sarcopenic obesity is the coexistance of sarcopenia and obesity. Modern sarcopenia definition includes low muscle mass, weak muscle strength (handgrip strength) and poor physical function (slow walking), although the clinical definition of each varies worldwide. The cut-points for low muscle mass for men and women using appendicular lean mass divided by height (kg/m2) are ≤7.0 and ≤5.4 in Asians, and ≤7.23 and ≤5.67 in Caucasians, respectively. The cut-points for weak handgrip strength (kg) for men and women are <26 and <18 in Asians, and <30 and <20 in Caucasians, respectively. The cut-point for slow walking is ≤0.8 m/s in men and women. Current data suggest the potential benefits of physical activity and fitness on sarcopenic obesity in older adults.

Effects of a progressive resistance exercise program with high-speed component on the physical function of older women with sarcopenic obesity: a randomized controlled trial

Background

Sarcopenic obesity is associated with disability in older people, especially in women. Resistance exercises are recommended for this population, but their efficacy is not clear.

Objective

To evaluate the effects of a progressive resistance exercise program with high-speed component on the physical function of older women with sarcopenic obesity.

Method

Twenty-eight women 65 to 80 years old, with a body mass index ≥30kg/m² and handgrip strength ≤21kg were randomly allocated to two groups. The experimental group underwent a 10-week resistance exercise program designed to improve strength, power, and endurance of lower-limb muscles, with open chain and closed chain exercises. The control group had their health status monitored through telephone calls. The primary outcomes were lower limb muscle performance measured by knee extensor strength, power and fatigue by isokinetic dynamometry, and mobility measured by the Short Physical Performance Battery and by gait velocity. The secondary outcome was health-related quality of life assessed by the SF-36 Questionnaire.

Results

The average rate of adherence was 85%, with few mild adverse effects. There were no significant between-group differences for any of the outcomes.

Conclusion

In this study, a progressive resistance exercise program with high-speed component was not effective for improving the physical function of older women with sarcopenic obesity.

Caloric restriction and aerobic exercise in sarcopenic and non-sarcopenic obese women: an observational and retrospective study

BACKGROUND

Sarcopenic obese (SO) individuals are a unique subset of subjects that combines obesity and sarcopenia. Traditional weight loss programmes including aerobic exercises may worsen their condition by further reducing their lean mass. The objective of this observational and retrospective study was to verify the effect of a mixed weight loss programme combining caloric restriction and exercise on body composition, and lipid-lipoprotein profile of obese women according to their sarcopenic status.

METHODS

One hundred and forty-six obese women (body mass index ≥ 30 kg/m(2) and fat mass ≥ 40%) participated to the 3 week usual and institutionalized weight-reducing programme combining a dietary plan (1400 ± 200 kcal/day) and aerobic exercise (1 h/day, 6 days/week) of a specialized medical institution. The lean body mass index (LMI; lean mass/height(2)) was calculated, and women in the lowest tertile of LMI were considered SO.

RESULTS

At baseline, SO women were older, and their body weight and LMI were lower than non-sarcopenic obese (N-SO) women (p < 0.05). N-SO and SO women similarly lost fat mass and improved their lipid-lipoprotein profile (p < 0.05), while differences in LMI between groups persisted at the end of the weight-reducing programme. Indeed, N-SO women lost lean mass (p < 0.05) while SO did not.

CONCLUSIONS

These findings suggest that a short weight loss programme combining caloric restriction and aerobic exercise may significantly reduce fat mass and improve lipid-lipoprotein profile in obese women, independently of their sarcopenic status. Such programmes may have deleterious effects on lean mass in N-SO subjects, only.

Skeletal muscle mass and body fat in relation to successful ageing of older adults: The multi-national MEDIS study

BACKGROUND

The determinants that promote successful ageing still remain unknown. The aim of the present work was to evaluate the role of skeletal muscle mass and body fat percentage (BF%), in the level of successful ageing.

METHODS

during 2005-2011, 2663 older (aged 65-100 years) from 21 Mediterranean islands and the rural Mani region (Peloponnesus) of Greece were voluntarily enrolled in the study. Appendicular skeletal muscle mass (ASM), skeletal muscle mass index (SMI) and BF% were calculated using population formulas. Dietary habits, energy intake, expenditure and energy balance were derived throughout standard procedures. A successful ageing index ranging from 0 to 10 was used.

RESULTS

The mean ASM mass was 24±6.0kg, the SMI was 0.84±0.21 and the BF% was 44%. Females had lower SMI and higher BF% in comparison with males, respectively [(SMI: 0.66±0.09 vs. 1.03±0.11; BF%: 51% vs. 34%, (p<0.001)]. High successful agers had better rates in ASM (p=0.01), SMI (p<0.001) and BF% (p<0.001), compared with the medium and low successful ones. Changes in SMI [b-coefficient (95% CI):2.14 (1.57 to 2.71)] were positively associated with successful ageing, while changes in BF% [b-coefficient (95% CI): -0.04 (-0.05 to -0.03)] were inversely associated with successful ageing. Results from sensitivity analysis showed that the effects of variations on body composition were consistent, less pronounced in the positive energy balance group and more pronounced among the oldest old.

CONCLUSIONS

Body composition changes seem to be associated with lower quality of life in the older adults, as measured through successful ageing.

Insulin resistance and sarcopenia: mechanistic links between common co-morbidities

Insulin resistance (IR) in skeletal muscle is a key defect mediating the link between obesity and type 2 diabetes, a disease that typically affects people in later life. Sarcopenia (age-related loss of muscle mass and quality) is a risk factor for a number of frailty-related conditions that occur in the elderly. In addition, a syndrome of 'sarcopenic obesity' (SO) is now increasingly recognised, which is common in older people and is applied to individuals that simultaneously show obesity, IR and sarcopenia. Such individuals are at an increased risk of adverse health events compared with those who are obese or sarcopenic alone. However, there are no licenced treatments for sarcopenia or SO, the syndrome is poorly defined clinically and the mechanisms that might explain a common aetiology are not yet well characterised. In this review, we detail the nature and extent of the clinical syndrome, highlight some of the key physiological processes that are dysregulated and discuss some candidate molecular pathways that could be implicated in both metabolic and anabolic defects in skeletal muscle, with an eye towards future therapeutic options. In particular, the potential roles of Akt/mammalian target of rapamycin signalling, AMP-activated protein kinase, myostatin, urocortins and vitamin D are discussed.

The FTO gene is associated with a paradoxically favorable cardiometabolic risk profile in frail, obese older adults

OBJECTIVE

Fat mass and obesity-associated (FTO) gene polymorphisms have been reported to be associated with differences in BMI, obesity, and type 2 diabetes. However, previous studies have been predominantly conducted in younger individuals across a spectrum of body weights, whereas little information is available on the older population. We examined the association of FTO gene polymorphisms with cardiometabolic risks among adults who were both obese (BMI≥30 kg/m) and older (age≥65 years).

METHODS

A total of 165 frail, obese older adults were genotyped for FTO (rs9939609 and rs8050136) single nucleotide polymorphisms and studied for associations with body weight and body composition, components and prevalence of the metabolic syndrome, insulin response to an oral glucose tolerance test, and levels of adipocytokines (e.g. leptin) and vitamin D.

RESULTS

Carriers of the A allele (CA/AA) of the FTO single nucleotide polymorphism rs8050136 had lower body weight, BMI, body fat, and trunk fat than those without the A allele (CC genotype; all P's<0.05). Moreover, genotype CA/AA was associated with lower levels of triglycerides and higher levels of high-density lipoprotein-cholesterol and carriers of this genotype showed a trend toward a lower waist circumference, resulting in a lower prevalence of metabolic syndrome than in CC genotype carriers. The insulin area under the curve during the oral glucose tolerance test was lower for genotype CA/AA. Despite the lower insulin levels, the glucose area under the curve was unchanged, resulting in a higher insulin sensitivity index. Leptin levels were also lower and adiponectin and 25-hydroxyvitamin levels tended to be higher for genotype CA/AA than for genotype CC. No differences were observed for rs9939609.

CONCLUSION

Unlike the results from studies in younger individuals, the risk A allele may confer a favorable cardiometabolic risk profile in obese older adults, suggesting selective survival of obese adults into old age. If confirmed in a larger sample of surviving obese older adults, these findings may have implications in the clinical approach to obesity in this population.

Prevalence of sarcopenic obesity in Germany using established definitions: Baseline data of the FORMOsA study

The prevalence of sarcopenic obesity in community-dwelling women 70 years and older according to established sarcopenia and obesity definitions averaged between 0 and 2.3 % and can thus be considered as relatively low. However, the converse argument that sarcopenic obesity was incompatible with an independent life cannot be confirmed.

INTRODUCTION

The primary aim of the study was to determine the prevalence of sarcopenic obesity (SO) in community-dwelling (CD) older females in Germany. The secondary aim was to assess whether these females really live independently and autonomously.

METHODS

A total of 1325 CD females 70 years and older living in the area of Erlangen-Nürnberg, Germany were assessed. Sarcopenia as defined by (a) the European Working Group on Sarcopenia in older people (EWGSOP) and (b) the International working group on Sarcopenia (IWGS) combined with obesity defined as (a) BMI ≥ 30 kg/m(2) (NIH) or (b) body-fat ≥ 35 % (WHO) was determined. In participants with SO, Barthel Index, care level and social network were retrospectively evaluated via personal interview.

RESULTS

Based on anthropometric data, family, education and social status, lifestyle, number and distribution of diseases and medication, the present cohort is representative for the corresponding German population. Sarcopenia prevalence was 4.5 % according to EWGSOP and 3.3 % according to the IWGS criteria. Obesity prevalence in our cohort averaged 19.8 % (BMI, NIH) and 63.8 % (body fat, WHO). The overlap between both factors (i.e. SO) ranged from 0 % (EWGSOP + NIH criteria) to 2.3 % (EWGSOP + WHO criteria). Factors that may represent limited autonomy or independence were very rarely identified in this SO cohort.

CONCLUSION

The prevalence of sarcopenic obesity in the CD (female) German population 70 years + is relatively low. With respect to our second research aim, the hypothesis that SO was incompatible with independent life was rejected. However, the latter finding should be addressed with more dedicated study designs.

Sarcopenic obesity and complex interventions with nutrition and exercise in community-dwelling older persons--a narrative review

One of the many threats to independent life is the age-related loss of muscle mass and muscle function commonly referred to as sarcopenia. Another important health risk in old age leading to functional decline is obesity. Obesity prevalence in older persons is increasing, and like sarcopenia, severe obesity has been consistently associated with several negative health outcomes, disabilities, falls, and mobility limitations. Both sarcopenia and obesity pose a health risk for older persons per se, but in combination, they synergistically increase the risk for negative health outcomes and an earlier onset of disability. This combination of sarcopenia and obesity is commonly referred to as sarcopenic obesity. The present narrative review reports the current knowledge on the effects of complex interventions containing nutrition and exercise interventions in community-dwelling older persons with sarcopenic obesity. To date, several complex interventions with different outcomes have been conducted and have shown promise in counteracting either sarcopenia or obesity, but only a few studies have addressed the complex syndrome of sarcopenic obesity. Strong evidence exists on exercise interventions in sarcopenia, especially on strength training, and for obese older persons, strength exercise in combination with a dietary weight loss intervention demonstrated positive effects on muscle function and body fat. The differences in study protocols and target populations make it impossible at the moment to extract data for a meta-analysis or give state-of-the-art recommendations based on reliable evidence. A conclusion that can be drawn from this narrative review is that more exercise programs containing strength and aerobic exercise in combination with dietary interventions including a supervised weight loss program and/or protein supplements should be conducted in order to investigate possible positive effects on sarcopenic obesity.

Optimizing Protein in the Older Adult

Aging is associated with specific physiological changes. One change that influences the functionality of an individual is the decrease in skeletal muscle. Research efforts to maintain skeletal muscle through dietary modifications have primarily focused on protein intake, including composition, quantity, and timing. Evidence demonstrates that adequacy, quality, and balance of protein intake are important; however, it should not replace the other dietary needs of the individual. The purpose of this article is to summarize the vast area of research regarding protein consumption in the aging population and place it in context of other nutritional concerns that affect this demographic. Efforts to educate older adults without providing overcomplicated guidelines will reduce the likelihood of individuals feeling overwhelmed, increasing dietary adherence.

Hypoenergetic diet-induced reductions in myofibrillar protein synthesis are restored with resistance training and balanced daily protein ingestion in older men

Strategies to enhance weight loss with a high fat-to-lean ratio in overweight/obese older adults are important since lean loss could exacerbate sarcopenia. We examined how dietary protein distribution affected muscle protein synthesis during energy balance (EB), energy restriction (ER), and energy restriction plus resistance training (ER + RT). A 4-wk ER diet was provided to overweight/obese older men (66 ± 4 yr, 31 ± 5 kg/m(2)) who were randomized to either a balanced (BAL: 25% daily protein/meal × 4) or skewed (SKEW: 7:17:72:4% daily protein/meal; n = 10/group) pattern. Myofibrillar and sarcoplasmic protein fractional synthetic rates (FSR) were measured during a 13-h primed continuous infusion of l-[ring-(13)C6]phenylalanine with BAL and SKEW pattern of protein intake in EB, after 2 wk ER, and after 2 wk ER + RT. Fed-state myofibrillar FSR was lower in ER than EB in both groups (P < 0.001), but was greater in BAL than SKEW (P = 0.014). In ER + RT, fed-state myofibrillar FSR increased above ER in both groups and in BAL was not different from EB (P = 0.903). In SKEW myofibrillar FSR remained lower than EB (P = 0.002) and lower than BAL (P = 0.006). Fed-state sarcoplasmic protein FSR was reduced similarly in ER and ER + RT compared with EB (P < 0.01) in both groups. During ER in overweight/obese older men a BAL consumption of protein stimulated the synthesis of muscle contractile proteins more effectively than traditional, SKEW distribution. Combining RT with a BAL protein distribution "rescued" the lower rates of myofibrillar protein synthesis during moderate ER.

Body mass index, Mini Nutritional Assessment, and their association with five-year mortality in very old people

OBJECTIVES

to investigate the prevalence of malnutrition and the association between Body Mass Index (BMI), Mini Nutritional Assessment (MNA) and five-year mortality in a representative population of very old (>85 years) people.

DESIGN

A prospective cohort study.

SETTING

A population-based study of very old people in northern Sweden and western Finland, living in institutional care or in the community.

PARTICIPANTS

Out of 1195 potential participants, 832 were included (mean age 90.2±4.6 years).

MEASUREMENTS

Nutritional status was assessed using BMI and MNA and the association of those two variables with five-year mortality was analyzed.

RESULTS

The mean BMI value for the whole population was 25.1±4.5 kg/m2, with no difference between genders (P=0.938). The mean MNA score was 22.5±4.6 for the whole sample, and it was lower for women than for men (P<0.001). Thirteen percent were malnourished (MNA<17) and 40.3% at risk of malnutrition (MNA 17-23.5) according to MNA. Also, 34.8% of those with a MNA score <17 still had a BMI value ≥22.2 kg/m2. A BMI value <22.2 kg/m2 and a MNA score<17 were associated with lower survival. The association with mortality seemed to be J-shaped for BMI, and linear for MNA.

CONCLUSIONS

Malnutrition according to MNA was common, but a substantial portion of those with a low MNA score still had a high BMI value, and vice versa. The association with mortality appeared to be J-shaped for BMI, and linear for MNA. The MNA seems to be a good measurement of malnutrition in very old people, and BMI might be misleading and could underestimate the prevalence of malnutrition, especially in women.

Synthesis and biological evaluation of novel structure-related hGHRH agonistic analogs

Activity and half-life play key roles in the application of GHRH analogues. The GHRH monomers produced in a solid synthesizer were incubated, respectively, in NH4OH solution and lyophilized to obtain their dimers. The activities, specificities, and receptor affinities of the GHRH dimers were evaluated in rGH release/inhibition, rACTH/LH/PRL release, pituitary homogenate binding, and fluorescent staining. Compared to hGHRH(1-44)NH2 (S), PP-hGHRH(1-44)-GGC-CGG-hGHRH(44-1)-PP (2D), P-hGHRH(1-44)-GGC-CGG-hGHRH(44-1)-P (2E), (1)P-hGHRH(2-44)-GGC-CGG-hGHRH(44-2)-(1)P (2F), or hGHRH(1-44)-GGC-CGG-hGHRH(44-1) (2Y) had potency of 104 ± 16.7%, 94 ± 32.6%, 114 ± 16.6%, or 122 ± 14.5% and similar specificities. The inhibition effect of GHIH on rGH stimulated by GHRH dimer was in dose-/time-dependent manner. The staining of FITC-labeled dimer showed cytomembrane distribution and the binding ranking was 2F>2D>2Y>2E>S. 2F presents the strongest activity and the highest affinity to pituitary cells. The dimer with (1)Pro-GHRH stimulates stronger rGH release than that with (1)Tyr-GHRH and the N-terminal single cyclic amino acid is required for the stimulation.

Weight loss and physical activity for disease prevention in obese older adults: an important role for lifestyle management

Weight loss in older adults has been a controversial topic for more than a decade. An obesity paradox has been previously described and the issue of weight status on health outcomes remains a highly debated topic. However, there is little doubt that physical activity (PA) has a myriad of benefits in older adults, especially in obese individuals who are inactive and have a poor cardiometabolic profile. In this review, we offer a critical view to clarify misunderstandings regarding the obesity paradox, particularly as it relates to obese older adults. We also review the evidence on PA and lifestyle interventions for the improvement of cardiorespiratory fitness, which can prevent disease and provide benefits to obese older adults, independent of weight changes.