Combined Impact of Positive Screen for Sarcopenia and Frailty on Physical Function, Cognition and Nutrition in the Community Dwelling Older Adult.

BACKGROUND: While sarcopenia and frailty independently contribute to functional impairment and disability, the combined impact resulting from their interplay is unclear. We investigated if functional, physical, cognitive, and nutritional measures were more adversely affected in community-dwelling older adults who were screened positive for both frailty and sarcopenia. METHODS: Using the FRAIL (≥1) and SARC-F (Strength, Assistance with walking, Rising from a chair, Climbing stairs, and Falls) (≥1) scales for screening, we categorized 200 participants (age, 67.9±7.9 years) as combined (both positive, 12.5%), intermediate (either positive, 25.5%), or robust (both negative, 62%). RESULTS: Comparisons of the three groups showed that the combined group had significantly worse functional ability (Frenchay Activities Index and Modified Barthel Index), physical performance (knee extension, gait speed, and Short Physical Performance Battery score), cognition/mood (Chinese Mini-Mental State Examination [CMMSE] score and Geriatric Depression Scale), and nutrition (Mini Nutritional Assessment [MNA] score) (p<0.05, one-way analysis of variance). Post-hoc comparisons revealed similar findings between the combined and robust groups, except for knee extension and CMMSE scores. Only MNA scores were significantly lower between the intermediate and robust groups. CONCLUSION: Functional ability, physical performance, and nutrition were more adversely affected in our study population of community-dwelling older adults who screened positive for both frailty and sarcopenia than in those who screened positive for either or neither, supporting the use of community screening for early detection and intervention for both frailty and sarcopenia as opposed to either alone.

Association of Monocyte Chemotactic Protein-1 and Dickkopf-1 with Body Composition and Physical Performance in Community-Dwelling Older Adults in Singapore.

OBJECTIVE: We aim to determine the association of monocyte chemotactic protein-1 (MCP-1) and dickkopft-1 (DKK-1) as potential biomarkers that may predict changes in body composition and physical performance in healthy older adults from Singapore. METHODS: Two-hundred community-dwelling older adults (mean age: 67.9 years; 68.5% females) were classified into elevated versus non-elevated groups based on quintile cut-offs of MCP-1 and DKK-1 levels (156.02 pg/mL and 606.31 pg/mL, respectively). Multiple linear regression was performed to examine the relationship between MCP-1 and DKK-1 with body composition and physical performance, adjusted for age, gender and ethnicity. RESULTS: MCP-1 was significantly associated with higher fat mass, fat mass index, percentage body fat, waist circumference and trunk-limb ratio for fat mass (all p<0.01), and repeated chair stand (p=0.004). DKK-1 was not associated with body composition and physical performance measures. Utilising the Asian Working Group for Sarcopenia (AWGS) 2019 criteria, there were 39 (19.5%) sarcopenia and 161 (80.5%) non-sarcopenia participants respectively, with MCP-1 levels significantly higher in sarcopenia compared with non-sarcopenia (p=0.046), but not for DKK-1 (p=0.525). CONCLUSIONS: Elevated MCP-1 are associated with changes in fat composition, physical performance and sarcopenia, suggesting its usefulness in identifying at-risk group with sarcopenic obesity.

Nutrition Mediates the Relationship between Osteosarcopenia and Frailty: A Pathway Analysis.

Osteosarcopenia is associated with increased risk of adverse outcomes such as falls and fractures. Its association with frailty is less well-described, particularly in independent community-dwelling older adults. Although nutrition plays a crucial role in maintaining bone and muscle health, the complex relationship between osteosarcopenia and nutrition in the pathogenesis of frailty remains to be elucidated. In this cross-sectional analysis of 230 independent, community-dwelling individuals (mean age 67.2 ± 7.4 years), we examined the associations between osteosarcopenia with nutritional status and frailty, and the mediating role of nutrition in the association between osteosarcopenia and frailty. Osteosarcopenia was defined as fulfilling both the Asian Working Group for Sarcopenia 2019 consensus definition (low relative appendicular skeletal muscle mass adjusted for height, in the presence of either of either low handgrip strength or slow gait speed) and T-score ≤ -2.5 SD on bone mineral densitometry. We assessed frailty using the modified Fried criteria and nutrition using the Mini-Nutritional Assessment. We performed multiple linear regression, followed by pathway analysis to ascertain whether nutrition mediates the relationship between osteosarcopenia and frailty. Our study population comprised: 27 (11.7%) osteosarcopenic, 35 (15.2%) sarcopenic, 36 (15.7%) osteoporotic and 132 (57.4%) normal (neither osteosarcopenic, sarcopenic nor osteoporotic). Osteosarcopenia (ß = 1.1, 95% CI 0.86-1.4) and sarcopenia (ß = 1.1, 95% CI 0.90-1.4) were significantly associated with frailty, but not osteoporosis. Nutrition mediated the association between osteosarcopenia and frailty (indirect effect estimate 0.09, bootstrap 95% CI 0.01-0.22). In conclusion, osteosarcopenia is associated with frailty and poorer nutritional status, with nutrition mediating the association between osteosarcopenia and frailty. Our findings support early nutritional assessment and intervention in osteosarcopenia to mitigate the risk of frailty.

Social Frailty Is Independently Associated with Mood, Nutrition, Physical Performance, and Physical Activity: Insights from a Theory-Guided Approach.

Notwithstanding the increasing body of evidence that links social determinants to health outcomes, social frailty is arguably the least explored among the various dimensions of frailty. Using available items from previous studies to derive a social frailty scale as guided by the Bunt social frailty theoretical framework, we aimed to examine the association of social frailty, independently of physical frailty, with salient outcomes of mood, nutrition, physical performance, physical activity, and life-space mobility. We studied 229 community-dwelling older adults (mean age 67.22 years; 72.6% females) who were non-frail (defined by the FRAIL criteria). Using exploratory factor analysis, the resultant 8-item Social Frailty Scale (SFS-8) yielded a three-factor structure comprising social resources, social activities and financial resource, and social need fulfilment (score range: 0-8 points). Social non-frailty (SNF), social pre-frailty (SPF), and social frailty (SF) were defined based on optimal cutoffs, with corresponding prevalence of 63.8%, 28.8%, and 7.4%, respectively. In logistic regression adjusted for significant covariates and physical frailty (Modified Fried criteria), there is an association of SPF with poor physical performance and low physical activity (odds ratio, OR range: 3.10 to 6.22), and SF with depressive symptoms, malnutrition risk, poor physical performance, and low physical activity (OR range: 3.58 to 13.97) compared to SNF. There was no significant association of SPF or SF with life-space mobility. In summary, through a theory-guided approach, our study demonstrates the independent association of social frailty with a comprehensive range of intermediary health outcomes in more robust older adults. A holistic preventative approach to frailty should include upstream interventions that target social frailty to address social gradient and inequalities.

Inter-muscular adipose tissue is associated with adipose tissue inflammation and poorer functional performance in central adiposity.

BACKGROUND: The presence of concomitant sarcopenia and obesity in sarcopenic obesity (SO) confers worse functional, morbidity and mortality outcomes compared to either alone. Excess adiposity and central redistribution of fats are associated with systemic inflammation and ectopic tissue fat infiltration in forms of Intermuscular adipose tissue (IMAT). Our study examines the profile of IMAT across a spectrum of body compositions and associations with physical performance and inflammatory biomarkers including Monocyte Chemoattractant Protein-1 (MCP-1), a novel biomarker of adipose tissue inflammation. METHODS: 187 community dwelling elderly participants were recruited and classified into 4 subgroups: normal, obese, sarcopenia and SO, using validated criteria for sarcopenia and waist circumference to define central obesity. We performed magnetic resonance imaging of mid-thigh sections to segment IMAT and muscle. Participants were assessed for muscle strength, physical performance and blood inflammatory biomarkers of interleukin-6, C-Reactive Protein and MCP-1. We examined correlation of IMAT(ratio) with muscle function measures and blood biomarkers. Multiple regression analyses were used to examine the association of body composition types and IMAT(ratio) with muscle function. RESULTS: IMAT(ratio) was highest in SO and obese groups. Overall, higher IMAT(ratio) is significantly associated with raised MCP-1, lower gait speed and muscle strength. SO had lowest scores in Short Physical Performance Battery (SPPB), gait speed, hand-grip and knee extension strength. IMAT(ratio) is independently associated with SPPB and handgrip strength, whilst SO is independently associated with muscle strength. CONCLUSION: Our results suggest the possible role of IMAT as a candidate imaging biomarker for adipose tissue inflammation and associated poorer functional outcomes in SO.

Automated assessment of thigh composition using machine learning for Dixon magnetic resonance images.

OBJECTIVES: To develop and validate a machine learning based automated segmentation method that jointly analyzes the four contrasts provided by Dixon MRI technique for improved thigh composition segmentation accuracy. MATERIALS AND METHODS: The automatic detection of body composition is formulized as a three-class classification issue. Each image voxel in the training dataset is assigned with a correct label. A voxel classifier is trained and subsequently used to predict unseen data. Morphological operations are finally applied to generate volumetric segmented images for different structures. We applied this algorithm on datasets of (1) four contrast images, (2) water and fat images, and (3) unsuppressed images acquired from 190 subjects. RESULTS: The proposed method using four contrasts achieved most accurate and robust segmentation compared to the use of combined fat and water images and the use of unsuppressed image, average Dice coefficients of 0.94 ± 0.03, 0.96 ± 0.03, 0.80 ± 0.03, and 0.97 ± 0.01 has been achieved to bone region, subcutaneous adipose tissue (SAT), inter-muscular adipose tissue (IMAT), and muscle respectively. CONCLUSION: Our proposed method based on machine learning produces accurate tissue quantification and showed an effective use of large information provided by the four contrast images from Dixon MRI.

The Case for Stage-Specific Frailty Interventions Spanning Community Aging to Cognitive Impairment.

OBJECTIVES: To explore factors associated with frailty across the continuum of healthy aging to cognitive impairment (mild cognitive impairment [MCI], mild and moderate Alzheimer disease [AD]). DESIGN: Cross-sectional study. SETTING: Senior activity centers and the outpatient memory clinic of a tertiary hospital. PARTICIPANTS: Community-dwelling and functionally independent adults aged 50 years and older and older adults attending the memory clinic with MCI, and mild and moderate AD diagnoses. METHODS: We recruited 299 participants comprising 200 cognitively healthy individuals, 16 with MCI, 68 with mild AD, and 15 with moderate AD. We collected measures of comorbidities, cognitive and functional performance, physical activity level, and anthropometric and nutritional status. Frailty was defined using Buchmann criteria, and sarcopenic obesity (SO) was defined using the Asian Working Group for Sarcopenia criteria and the revised National Cholesterol and Education Panel-obesity definition of waist circumference. Multiple logistic regression was performed to identify factors associated with frailty as a whole group and separately based on cognitive subgroups. RESULTS: There were 16.7% of patients who met frailty criteria. Frailty prevalence was lowest in the well elderly (3.5%) and subsequently followed a U-shaped prevalence from MCI to mild and moderate AD, respectively. Specific univariate differences were noted in age, hypertension, ischemic heart disease, depressive symptoms, social differences, and functional scores. Multivariable logistic regression showed age, cognitive status, and SO to be significantly associated with frailty status. Subgroup analysis showed only SO to be significant (odds ratio [OR] 15.55, 95% confidence interval [CI] 1.63-148.42) in well elderly and only cognition to be associated with frailty (OR 0.89, 95% CI 0.80-0.99) among the cognitively impaired. CONCLUSION: Our findings lend initial support to the case for stage-specific interventions for physical frailty with the focus on SO in healthy community-dwelling older persons and cognitive-based measures in older adults with cognitive impairment. The accurate clinical phenotyping would then set the stage for future potential investigative therapies along these specific lines, rather than an undifferentiated approach.

Monocyte chemoattractant protein-1: a proinflammatory cytokine elevated in sarcopenic obesity.

OBJECTIVE: Sarcopenic obesity (SO) is associated with poorer physical outcomes and functional status in the older adult. A proinflammatory milieu associated with central obesity is postulated to enhance muscle catabolism. We set out to examine associations of the chemokine monocyte chemoattractant protein-1 (MCP-1) in groups of older adults, with sarcopenia, obesity, and the SO phenotypes. METHODS: A total of 143 community dwelling, well, older adults were recruited. Cross-sectional clinical data, physical performance, and muscle mass measurements were collected. Obesity and sarcopenia were defined using revised National Cholesterol Education Program (NCEP) obesity guidelines and those of the Asian Working Group for Sarcopenia. Serum levels of MCP-1 were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: In all, 25.2% of subjects were normal, 15.4% sarcopenic, 48.3% obese, and 11.2% were SO. The SO groups had the lowest appendicular lean mass, highest percentage body fat, and lowest performance scores on the Short Physical Performance Battery and grip strength. The MCP-1 levels were significantly different, with the highest levels found in SO participants (P<0.05). CONCLUSION: Significantly raised MCP-1 levels in obese and SO subjects support the theory of chronic inflammation due to excess adiposity. Longitudinal studies will reveal whether SO represents a continuum of obesity causing accelerated sarcopenia and cardiovascular events, or the coexistence of two separate conditions with synergistic effects affecting functional performance.