Reduction of Resting Energy Expenditure and Sarcopenic Obesity in Adults with Overweight and Obesity: A Brief Report

Obesity-induced tissue alterations resist weight loss: A mechanistic review

Interventions aimed at weight control often have limited effectiveness in combating obesity. This review explores how obesity-induced dysfunction in white (WAT) and brown adipose tissue (BAT), skeletal muscle, and the brain blunt weight loss, leading to retention of stored fat. In obesity, increased adrenergic stimulation and inflammation downregulate β-adrenoreceptors and impair catecholaminergic signalling in adipocytes. This disrupts adrenergic-mediated lipolysis, diminishing lipid oxidation in both white and brown adipocytes, lowering thermogenesis and blunting fat loss. Emerging evidence suggests that WAT fibrosis is associated with worse weight loss outcomes; indeed, limiting collagen and laminin-α4 deposition mitigates WAT accumulation, enhances browning, and protects against high-fat-diet-induced obesity. Obesity compromises mitochondrial oxidative capacity and lipid oxidation in skeletal muscle, impairing its ability to switch between glucose and lipid metabolism in response to varying nutrient levels and exercise. This dysfunctional phenotype in muscle is exacerbated in the presence of obesity-associated sarcopenia. Additionally, obesity suppresses sarcolipin-induced sarcoplasmic reticulum calcium ATPase (SERCA) activation, resulting in reduced oxidative capacity, diminished energy expenditure, and increased adiposity. In the hypothalamus, obesity and overnutrition impair insulin and leptin signalling. This blunts central satiety signals, favouring a shift in energy balance toward energy conservation and body fat retention. Moreover, both obese animals and humans demonstrate impaired dopaminergic signalling and diminished responses to nutrient intake in the striatum, which tend to persist after weight loss. This may result in enduring inclinations toward overeating and a sedentary lifestyle. Collectively, the tissue adaptations described pose significant challenges to effectively achieving and sustaining weight loss in obesity.

Understanding sarcopenic obesity in young adults in clinical practice: a review of three unsolved questions

INTRODUCTION

Our aim was to summarize the available literature on three yet unsolved questions, namely: 1) the dilemma surrounding definition of sarcopenic obesity (SO), especially in young adults; 2) the potential impact of this phenotype on weight-loss programme outcomes; and 3) the strategies for optimum management (prevention/treatment) of SO in clinical practice.

EVIDENCE ACQUISITION

A literature review using the PubMed/Medline database was conducted, and data were summarized based on a narrative approach.

EVIDENCE SYNTHESIS

Firstly, SO can be screened by the 30-sec sit-to-stand test; ≤25 and ≤21; and confirmed by the ratio of (appendicular lean mass/Body Mass Index) ≤0.789 and 0.512 in males and females, respectively. Secondly, SO is associated with impaired physical fitness, reduced resting energy expenditure and an inactive lifestyle, that seems to negatively impact on weight-management outcomes, namely increasing early dropout and difficulty in maintaining weight loss in the long term. Finally, prevention/treatment of SO in young adults must be realized through tailored lifestyle intervention (diet+exercise) to preserve and improve strength and muscle mass, even where weight loss is necessary.

CONCLUSIONS

Our findings have clinical implications since they may help in screening, managing and improving the weight-loss outcomes of patients with SO in clinical settings.

Approaching Sarcopenic Obesity in Young and Middle-Aged Female Adults in Weight Management Settings: A Narrative Review

This paper presents a review of the available literature on sarcopenic obesity (SO) in young and middle-aged female adults with obesity in weight management settings. A literature review using the PubMed/Medline and Science Direct databases was conducted, and the data were summarized through a narrative approach. Firstly, some physical performance tests and questionnaires are available for screening young and middle-aged female adults with a high risk of SO. Secondly, these patients can undergo instrumental measurements such as dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA) to confirm or reject a diagnosis of SO, applying definitions that account for body mass. Thirdly, SO is a prevalent phenotype in females seeking weight management treatment, as well as being strongly associated (vs. non-SO) with obesity-related comorbidities that need to be promptly managed, initially with nutritional programs or/and in combination with medications. Finally, patients with SO have a reduced baseline resting energy expenditure and more sedentary behaviors, which seem to account for the relationship between SO and poorer weight management outcomes, such as a higher early dropout rate and major later difficulties in weight loss maintenance. Therefore, specific strategies for personalized weight management programs for patients with SO should be incorporated to determine a successful management of this phenotype.

Can Intentional Weight Loss Ameliorate Sarcopenia in Individuals with Obesity? A Longitudinal Interventional Study

Little remains known regarding the impact of weight loss on sarcopenic obesity (SO), and for this reason we aimed to assess the relationship between the two during a weight management program. Body composition was measured at baseline and six-month follow-up using the Tanita BC-418, and step measurements were obtained daily over a period of six months using an Omron HJ-320 pedometer, in 41 adults of both genders with obesity. The participants were then categorized according to the presence or absence of SO. After a significant weight loss, an improvement in the appendicular skeletal mass (ASM) to weight ratio (24.5 ± 3.5 vs. 26.2 ± 3.6, p < 0.01), indicated a decrease in the prevalence of SO by 12.2%. Moreover, these findings were confirmed by logistic regression analysis revealing a significant WL% ≥ 5% combined with an active lifestyle (i.e., ≥8000 steps/day), decreased the risk of SO by 91% (OR = 0.09; 95% CI: 0.02–0.56), after adjusting for age and gender. In conclusion, in a weight management setting, a personalized program for individuals with SO that incorporates new strategies in terms of weight loss and physical activity targets may be adopted to improve the sarcopenia-related index and reduce the prevalence of SO in this population.

The Relationship between Sarcopenic Obesity, Weight-Loss and Maintenance Outcomes during Obesity Management: Are Additional Strategies Required?

The lack of long-term maintenance of the weight loss achieved during weight-management programs is the major cause of failure in obesity treatments. The identification of factors related to this outcome has clinical implications. Therefore, we aimed to assess the relationship between sarcopenic obesity (SO) and the weight-loss percentage (WL%). The WL% was measured at the six-month follow-up and after more than 12 months, in 46 adult participants with obesity, during an individualized weight-management program where participants were categorized as having or not having SO at the baseline. At the six-month follow-up, participants with SO did not display a significant difference in terms of WL%, when compared to those without SO (-10.49 ± 5.75% vs. -12.73 ± 4.30%; p = 0.148). However, after a longer term (i.e., >12 months), the WL% appeared to be significantly lower in the former (SO vs. non-SO) (-7.34 ± 6.29% vs. -11.43 ± 4.31%; p = 0.024). In fact, partial correlation analysis revealed a relationship between SO at the baseline and a lower WL% after more than 12 months (ρ = -0.425, p = 0.009), after controlling for age, sex, and body mass index (BMI). Participants with SO appeared to face more difficulties in maintaining the achieved WL over a longer term (>12 months follow-up) by comparison with their counterparts (i.e., non-SO). Should this finding be replicated in larger-sample studies, new strategies should be adopted for these patients in order to improve this clinical outcome, especially during the weight-maintenance phase.

Association Between Sarcopenic Obesity and Metabolic Syndrome in Adults: A Systematic Review and Meta-Analysis

Background

In the last two decades, a new phenotype termed Sarcopenic Obesity (SO), in which sarcopenia and obesity coexist, has emerged.

Objective

The aim of this systematic review and meta-analysis was first to assess the prevalence of Metabolic syndrome (Mets) among individuals with and without SO, and second, to determine if SO may increase the relative risk of Mets.

Methods

This study was conducted in adherence to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines and the data were collated by means of meta-analysis and narrative synthesis.

Results

Twelve studies including a total of 11,308 adults with overweight or obesity of both genders met the inclusion criteria and were reviewed, revealing two main findings. First, a similar overall prevalence of Mets in individuals with SO (61.49%; 95% CI: 52.19-70.40) when compared to those without SO (56.74%; 95% CI: 47.32-65.93) was identified. Second, the presence of SO appears not to increase the risk of Mets with respect to those without SO (RR = 1.08, 95% CI: 0.99-1.17, p = 0.07).

Conclusion

No higher prevalence of Mets among individuals with SO when compared to those with obesity only, nor a significant association between SO and a higher risk of Mets was found.

Sarcopenic Obesity Predicts Early Attrition in Treatment-Seeking Patients with Obesity: A Longitudinal Pilot Study

Attrition is a major cause of failure in obesity treatment, which is still not fully understood. The identification of factors related to this outcome is of clinical relevance. We aimed to assess the relationship between sarcopenic obesity (SO) and early attrition. Early attrition was assessed at six months, and two groups of patients were selected from a large cohort of participants with overweight or obesity enrolled at the Outpatient Clinic of the Department of Nutrition and Dietetics at Beirut Arab University (Lebanon). Body composition was measured using a bioimpedance analyser (Tanita BC-418) and participants at baseline were categorized as having or not having SO. The “dropout group” included 72 participants (cases) compared to 31 participants (controls) in the “completer group”, with the former displaying a higher prevalence of SO than the latter (51.0% vs. 25.8%; p = 0.016). In the same direction, Poisson regression analysis showed that SO increased the relative risk of dropout by nearly 150% (RR = 1.45; 95% CI = 1.10–1.89; p = 0.007) after adjustment for age, gender, body mass index (BMI), age at first dieting, sedentary habits and weight-loss expectation. In conclusion, in a “real-world” outpatient clinical setting, the presence of SO at baseline increases the risk of dropout at six months. New directions of future research should be focused on identifying new strategies to reduce the attrition rate in this population.

The Impact of Sarcopenic Obesity on Health-Related Quality of Life of Treatment-Seeking Patients with Obesity

BACKGROUND

There is a paucity of studies on health-related quality of life (HRQoL) and sarcopenic obesity (SO).

OBJECTIVE

This study aimed to assess the potential association between SO and impaired HRQoL.

METHODS

The ORWELL 97 questionnaire was used to assess HRQoL and body composition was measured using a bioimpedance analyser (Tanita BC-418) in 130 patients with obesity, referred to the Nutritional and Weight Management outpatient clinic of Beirut Arab University in Lebanon. Participants were then categorized on the basis of the absence or presence of SO.

RESULTS

Sixty-four of the 130 participants met the criteria for SO (49.2%) and displayed significantly higher total ORWELL 97 scores than those in the group without SO (64.00 vs. 41.00, p=0.001), indicative of poorer HRQoL. Linear regression analysis showed that SO was associated with an increase in ORWELL 97 scores by nearly 24 units (β=24.35, 95% CI=11.45-37.26; p<0.0001). Moreover, the logistic regression analysis showed that SO increased the odds of clinically significant impairment of HRQoL (ORWELL 97 score ≥74.25) by nearly seven-fold (OR=7.37, 95% CI=1.92-28.39; p=0.004).

CONCLUSION

Our findings show that the presence of SO was associated with increased impairment of HRQoL that reaches clinical significance when compared to obesity only. Future studies are needed to clarify whether this may influence clinical outcomes. If this is shown to be the case, weight management programs should incorporate additional strategies to improve HRQoL in individuals with SO.

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.