Sarcopenic obesity is associated with frailty among community-dwelling older adults: findings from the WCHAT study

Detecting sarcopenia in obesity: emerging new approaches

PURPOSE OF REVIEW

Sarcopenic obesity is a likely common, but certainly underestimated obesity phenotype, with an important negative clinical impact. Its definition and diagnosis have however remained elusive until recently.

RECENT FINDINGS

Substantial progress has been recently made in sarcopenic obesity diagnostic tools, with the first international consensus proposed by the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO). Very encouraging results emerge from initial implementation of the ESPEN-EASO algorithm. In addition, even more recent progress in global consensus on sarcopenia conceptual definition is likely to further enhance consistency in sarcopenic obesity identification. The latter Global Leadership Initiative on Sarcopenia (GLIS) initiative also adopted a new definition of muscle specific strength. Its inclusion in sarcopenia diagnostic constructs opens the possibility of its potential evaluation in sarcopenic obesity, also considering the emerging positive impact of obesity treatment and fat loss on muscle functional parameters.

SUMMARY

New consensus tools for sarcopenic obesity diagnosis are likely to improve awareness, understanding, identification and treatment of this under-recognized obesity phenotype.

Association of the dietary inflammatory index with sarcopenic obesity and frailty in older adults

OBJECTIVES

This study examined whether a higher dietary inflammatory index (DII®) is associated with the risk of sarcopenic obesity (SO) and frailty among Korean older adults.

METHODS

A total of 950 participants aged 70-84 years, who completed the baseline nutrition survey of the Korean Frailty and Aging Cohort Study, were included in the analysis. The DII, quantifying the dietary inflammatory potential, was calculated using 23 foods and nutrients as assessed by a 24-h dietary recall. SO was defined as the coexistence of sarcopenia (dual-energy X-ray absorptiometry-measured appendicular skeletal muscle mass index of < 7.0 for males; <5.4 for females) and abdominal obesity (waist circumference of ≥ 90 cm for males; ≥85 cm for females). Frailty status was assessed using the Fried frailty index (range, 0-5), a simple tool for defining frailty that consists of three or more of five frailty items. Multinomial logistic regression models were used to estimate odds ratios (ORs) with 95% confidence intervals (CIs), adjusting for confounders.

RESULTS

The prevalence of SO and frailty was 9.8% and 10.8%, respectively. The DII was significantly higher in the frail group (2.7) compared to the robust and SO groups (2.0 vs. 1.8) (P < 0.001). Among nutrients and foods included in the DII, the frail group exhibited lower vitamin E, niacin, vitamin B6, energy, and protein intakes than the robust and SO groups. Multivariable-adjusted OR (95% CI) for frailty versus robust (comparing DII tertile 3 to tertile 1) was 2.3 (1.1-4.8; P-trend = 0.02). However, no significant association was observed between the DII and SO (OR, 1.1; 95% CI, 0.5-2.1; P-trend = 0.6).

CONCLUSIONS

A higher DII score was associated with increased odds of frailty but not with SO in Korean older adults, suggesting that proinflammatory diets have a greater impact on frailty than that on SO in the older population.

Sarcopenic obesity and pre-sarcopenia contribute to frailty in community-dwelling Italian older people: data from the FRASNET study

BACKGROUND

The ageing process is characterized by a change of body composition with an increase of fat mass and a reduction of muscle mass. Above a certain threshold these alterations configure a condition named sarcopenic obesity (SO). SO is associated with physical frailty in Asian and Brazilian populations. SO impacts on physical frailty in other ethnic groups but its influence on general frailty which is multidimensional and includes cognitive, social and physical factors, remain insufficiently explored in the Italian population.

METHODS

Frailty was measured in community dwelling Italian older adults enrolled in the FRASNET study with the frailty index (FI). The FI quantifies frailty as the ratio of the number of present health deficits to the total number of health deficits considered. Regression analyses were performed to assess the association between body composition categories and frailty. Classification and regression tree models were run to evaluate the frailty predictors.

RESULTS

One Thousand One Hundred Fourteen participants of the FRASNET study were included in the present analysis. The sample was composed for the 60.5% by females and its median age was 72 years. The median FI score was 0.11 (IQR 0.07-0.20); 234 individuals (21%) were frail (FI ≥ 0.25). SO (B 0.074, 95% C.I. 0.05-0.1, p < 0.001) and pre-sarcopenia (without obesity B 0.03, 95% C.I, 0.007-0.044, p < 0.001, with obesity B 0.11, 95% C.I. 0.05-0.16, p < 0.001) were associated with frailty. Fat mass percentage predicted frailty in people aged 65-70 years whereas, muscle strength predicted general frailty in people aged 70-81 years.

CONCLUSION

Pre-sarcopenia and SO represent potentially treatable predictors of frailty.

Sarcopenic obesity in older adults: a clinical overview

Sarcopenic obesity is characterized by a concurrent decline in muscle mass and function, along with increased adipose tissue. Sarcopenic obesity is a growing concern in older adults owing to significant health consequences, including implications for mortality, comorbidities and risk of developing geriatric syndromes. A 2022 consensus statement established a new definition and diagnostic criteria for sarcopenic obesity. The pathophysiology of this condition involves a complex interplay between muscle, adipose tissue, hormonal changes, inflammation, oxidative stress and lifestyle factors, among others. Sarcopenic obesity is treated with a range of management approaches, such as lifestyle interventions, exercise, nutrition and medical therapies. Emerging therapies that were developed for treating other conditions may be relevant to sarcopenic obesity, including novel pharmacological agents and personalized approaches such as precision medicine. In this Review, we synthesize the current knowledge of the clinical importance of sarcopenic obesity, its assessment and diagnosis, along with current and emerging management strategies.

Prevalence of sarcopenic obesity in the older non-hospitalized population: a systematic review and meta-analysis

BACKGROUND

Sarcopenic obesity emerges as a risk factor for adverse clinical outcomes in non-hospitalized older adults, including physical disabilities, metabolic diseases, and even mortality. In this systematic review and meta-analysis, we investigated the overall SO prevalence in non-hospitalized adults aged ≥ 65 years and assessed the sociodemographic, clinicobiological, and lifestyle factors related to SO.

METHODS

We searched the PubMed, Embase, Cochrane Library, and Web of Science databases for studies reporting the prevalence of SO from database inception to October 2023. Two researchers independently screened the literature, evaluated the study quality, and extracted the data. Both fixed- and random-effects models were used in the meta-analysis to estimate the pooled SO prevalence and perform subgroup analyses. Publication and sensitivity bias analyses were performed to test the robustness of the associations.

RESULTS

Among 46 studies eligible for review and a total of 71,757 non-hospitalized older adults, the combined prevalence of SO was 14% (95% CI:11-17%, I2 = 99.5%, P < 0.01). Subgroup analysis according to lifestyle factors demonstrated that the SO prevalence was 17% (95% CI: 8-29%, I2 = 99.5%, P < 0.01) in older adults without exercise habits. Regarding clinicobiological factors, older adults with a history of falls (15% [95% CI: 10-22%, I2 = 82%, P < 0.01]), two or more chronic diseases (19% [95% CI: 10-29%, I2 = 97%, P < 0.01]), functional impairment (33% [95% CI: 29-37%, I2 = 0%, P = 0.95]), cognitive impairment (35% [95% CI: 9-65%, I2 = 83%, P = 0.02]), osteoporosis (20% [95% CI: 8-35%, I2 = 96%, P < 0.01]), high fasting glucose level (17% [95% CI: 1-49%, I2 = 98%, P < 0.01]), or the use of antipsychotics (13% [95% CI: 2-28%, I2 = 0%, P = 0.32]) exhibited a higher SO prevalence.

CONCLUSION

SO prevalence is high among non-hospitalized older adults, especially those with functional and cognitive impairments. Thus, SO is a potential problem for the aging population; implementation of planned interventions in the community is needed to reduce the prevalence and adverse outcomes of SO.

Approaching the Sarcopenic Patient with Nonalcoholic Steatohepatitis-related Cirrhosis

Sarcopenia is a well-known complication of chronic liver disease (CLD), and it is almost always observed in patients with cirrhosis, at least in those with decompensated disease. Since nonalcoholic fatty liver disease (NAFLD), recently renamed metabolic dysfunction-associated steatotic liver disease (MASLD), is becoming the leading cause of end-stage liver disease, a new scenario characterized by the frequent coexistence of NAFLD, obesity, and sarcopenia is emerging. Although it is not yet resolved whether the bidirectional relationship between sarcopenia and NAFLD subtends causal determinants, it is clear that the interaction of these two conditions is associated with an increased risk of poor outcomes. Notably, during the course of CLD, deregulation of the liver-muscle-adipose tissue axis has been described. Unfortunately, owing to the lack of properly designed studies, specific therapeutic guidelines for patients with sarcopenia in the context of NAFLD-related CLD have not yet been defined. Strategies aimed to induce the loss of fat mass together with the maintenance of lean body mass seem most appropriate. This can be achieved by properly designed diets integrated with specific nutritional supplementations and accompanied by adequate physical exercise. Future studies aiming to add to the knowledge of the correct assessment and approach to sarcopenia in the context of NAFLD-related CLD are eagerly awaited.

Individual and combined associations of sarcopenia, osteoporosis and obesity with frailty in a multi-ethnic asian older adult population

BACKGROUND

We explored the relationships between sarcopenia (SP), osteoporosis (OP), obesity (OB), (alone and in combination) with physical frailty (PF) in a multi-ethnic, population-based study of Asians aged ≥ 60 years.

METHODS

Participants were enrolled from the PopulatION HEalth and Eye Disease PRofile in Elderly Singaporeans Study (PIONEER) study. PF was defined using the modified Fried phenotype; SP using the Asian Working Group for Sarcopenia 2019; OP using bone mineral density scores; and OB using the fat mass index. Modified Poisson regression models investigated the associations between exposures and PF, and the relative excess rates of PF due to interactions (RERI) to determine synergistic or antagonistic interactions.

RESULTS

Of the 2643 participants, 54.8% was female; and 49.8%, 25.1%, 25.0% were Chinese, Indians, and Malays, respectively. 25%, 19.0% and 6.7% participants had OB only, SP only, and OP only, respectively. A total of 356 (17.5%), 151 (7.4%) and 97 (4.8%) had osteosarcopenia (OSP), sarcopenic obesity (SOB) and osteo-obesity (OOB), respectively; while 70 (3.5%) had all 3 morbid conditions (osteosarcopenic obesity, OSO). Both SP only and OB only were strongly associated with increased rates of PF (RR: 2.53, 95% CI: 1.95, 3.29; RR: 2.05, 95% CI: 1.58, 2.66 respectively); but not OP. Those with OSP, OOB and SOB were also associated with high risks of PF (RR: 2.82, 95% CI: 2.16, 3.68; RR: 2.34, 95% CI: 1.69, 3.23; and RR: 2.58, 95% CI: 1.95, 3.41, respectively) compared to robust individuals. Critically, individuals with OSO had the highest relative risk of having PF (RR: 3.06, CI: 2.28, 4.11). Only the sarcopenia-obesity interaction was significant, demonstrating negative synergism (antagonism). The concurrent presence of SP and OB was associated with a 100% lower rate of PF compared to the sum of the relatively rates of SP only and OB only.

CONCLUSION

The prevalence of SP, OB and OP, alone and combined, is substantial in older Asians and their early identification is needed to mitigate the risk of frailty. OB may interact with SP in an antagonistic manner to moderate rates of frailty. Further longitudinal studies are needed to address causality and mechanistic underpinnings our findings.

Sarcopenic Obesity Burden, Determinants, and Association With Risk of Frailty, Falls, and Functional Impairment in Older Adults With Diabetes: A Propensity Score Matching Analysis

BACKGROUND

Sarcopenic obesity (SO) is a medical and functional state characterized by the coexistence of excessive adipose tissue and sarcopenia inside an individual. Recent epidemiological studies suggest a rising prevalence of SO in patients with diabetes mellitus (DM) probably due to the conducive environment resulting from adipose tissue dysfunction and muscle wasting accelerated by insulin resistance, chronic inflammation, and altered protein metabolism. Individuals with SO may have higher risk of experiencing falls, frailty, and disabilities due to compromised musculoskeletal integrity, gait abnormalities, and reduced functional capacity. The primary study objective was to determine the prevalence and predictors of SO among older adults with a history of DM. The secondary objective was to assess the association of falls, frailty, and functional disability with SO in patients with DM.

METHODOLOGY

This cross-sectional study analyzed data from the nationally representative Longitudinal Aging Study in India (LASI) Wave 1, focusing on individuals aged 60 and above, with an emphasis on diabetes. SO was assessed using the Asian Working Group for Sarcopenia criteria. Propensity score matching (PSM), logistic regression, and mediation analysis were used to explore relationships between diabetes, SO, and health outcomes (falls, frailty, and disabilities).

RESULTS

Among 31,902 participants aged 60 and above, 14.26% had diabetes, and 17.67% of those with diabetes exhibited SO. Female gender (aOR = 2.63) and urban residence (aOR = 1.40) were significantly associated with higher odds of SO in individuals with diabetes. PSM analysis revealed a 9.0% higher likelihood of SO in older adults with DM than those without DM. SO was further linked to increased risk of falls, frailty, and various levels of activities of daily living (ADL) and instrumental activities of daily living (IADL) disabilities, with significant mediation effects ranging from 3.67% to 45.81%.

CONCLUSIONS

Diabetes substantially increases the risk of SO and associated functional disability with the risk of falls in older adults. Standard diabetes care should integrate health promotion especially nutrition to mitigate the risk of SO-linked functional disability and falls.

Sarcopenic Obesity and Risk of Disability in Community-Dwelling Japanese Older Adults: A 5-Year Longitudinal Study

OBJECTIVES

Previous studies have indicated that sarcopenic obesity is a risk factor for disability onset. However, these studies had disparities in terms of criteria for sarcopenia, study design, or study population. No longitudinal study has investigated the effect of sarcopenic obesity on disability onset in an Asian population using the Asian Working Group for Sarcopenia 2019 criteria for sarcopenia definition. Herein, we aimed to investigate the longitudinal effect of sarcopenic obesity on disability onset in Japanese older adults and extend the generalizability of results to other populations.

DESIGN

Longitudinal cohort study.

SETTING AND PARTICIPANTS

A total of 4197 Japanese older adults (mean age 74.6 ± 5.0 years, 54.2% women) formed our study population.

MEASUREMENTS

Sarcopenia was identified using the Asian Working Group for Sarcopenia 2019 algorithm. Obesity was determined when body fat percentage was ≥25%, or when visceral fat content was ≥100 cm2 for either sex. Disability onset was defined as a new case of long-term care insurance system certification for 5 years from baseline. Missing values were managed with multi-imputation. Cox proportional hazard regression analysis was used with disability onset as dependent variable and group (nonsarcopenia/nonobesity as a reference, nonsarcopenia/obesity, sarcopenia/non-obesity, possible sarcopenia/obesity, possible sarcopenia/non-obesity, sarcopenic obesity) as explanatory variable, and was adjusted for potential confounding factors.

RESULTS

When the nonsarcopenia/nonobesity group was used as the reference category, other groups such as possible-sarcopenia/nonobesity [hazard ratio (HR) 1.38, 95% confidential interval (95% CI) 1.29‒1.47, P < .028], possible-sarcopenia/obesity (HR 1.54, 95% CI 1.46‒1.62 P < .001), sarcopenia/nonobesity (HR 2.09, 95% CI 1.96‒2.23, P < .001), and sarcopenic obesity (HR 2.48, 95% CI 2.24‒2.75, P < .001) showed significantly increased HRs.

CONCLUSIONS AND IMPLICATIONS

The risk of disability onset because of sarcopenic obesity was exceedingly higher compared with sarcopenia alone among community-dwelling older adults in Japan The health providers should consider assessing the co-existence of sarcopenia and obesity to screen for the risk of disability onset in the community-dwelling population.

Waist-to-calf circumstance ratio and cognitive function among Chinese older adults: Mediating roles of physical performance and social activity

Background

In light of the potentially detrimental effects of central fat and decreased muscle mass on cognitive function, it would be beneficial to learn more about the mediating mechanisms underpinning the association between the two. The purpose of this study is to determine the association between waist-to-calf circumstance ratio (WCR) and cognitive function, as well as to investigate whether physical performance and social activity mediate the relationship between WCR and cognitive function among older Chinese adults.

Methods

An analysis of 9,652 older Chinese adults was conducted during the 2018 wave of the Chinese Longitudinal Health Longevity Survey (CLHLS). The Mini-Mental State Examination (MMSE) and a self-reported scale were used to measure cognitive function, physical performance, and social activity, respectively. Multiple linear regression and mediation analyses were conducted.

Results

The findings suggest that a high WCR had a significant negative association with cognitive function (B = -0.535, 95% CI: -0.754, -0.317). Mediation analysis revealed that a high WCR influenced old adults' cognitive function in three ways: first, through the partial mediating effect of physical performance (B = -0.270; 95% CI: -0.340, -0.203); second, through the partial mediating effect of social activity (B = -0.035; 95% CI: -0.055, -0.017); and third, through the serial mediating effects of physical performance and social activity (B = -0.021, 95% CI: -0.029, -0.015).

Conclusion

The study results suggest the adverse impact of a high WCR on older adults' cognitive function, and the possible mechanisms of physical performance and social activity by which the association takes place. Multidimensional health and social interventions aimed at improving physical, social, and cognitive functioning among older adults with sarcopenic obesity are recommended.