A systematic review and meta-analysis of the prevalence and correlation of mild cognitive impairment in sarcopenia

Mild cognitive impairment predicts the onset of Sarcopenia: a longitudinal analysis from the English Longitudinal Study on Ageing

BACKGROUND

Mild cognitive impairment (MCI) and sarcopenia are two common conditions in older people. It is not widely known if MCI could predict the onset of sarcopenia. Therefore, we aimed to investigate whether MCI could predict the occurrence of sarcopenia in a population of older adults.

METHODS

In the ELSA (English Longitudinal Study on Ageing), MCI was defined as the absence of dementia, preserved functional capacity and low performance in three objective cognitive tests. Sarcopenia was diagnosed as having low handgrip strength and low skeletal muscle mass index during follow-up. The longitudinal association between MCI at the baseline and incident sarcopenia was assessed using a multivariable logistic regression model, reporting the data as adjusted odds ratios (OR) and 95% confidence intervals (95%CI).

RESULTS

3,106 participants (mean age of 63.1 years; 55.3% males) were included. People with MCI reported significantly lower mean handgrip strength values and Skeletal Mass Index (SMI), as well as a higher prevalence of obesity at baseline. At baseline, 729 people had MCI and during the ten years follow-up period, 12.1% of the initial population included had sarcopenia. On multivariate analysis, adjusted for 18 potential confounders, the presence of MCI (OR = 1.236; 95%CI: 1.090-1.596, p = 0.01) significantly predicted the onset of sarcopenia during follow-up.

CONCLUSION

The presence of MCI at baseline was associated with a higher incidence of sarcopenia at ten-years follow-up, demonstrating a likely role of MCI as a predictor of the onset of sarcopenia in older people.

SuperAgers and centenarians, dynamics of healthy ageing with cognitive resilience

Graceful healthy ageing and extended longevity is the most desired goal for human race. The process of ageing is inevitable and has a profound impact on the gradual deterioration of our physiology and health since it triggers the onset of many chronic conditions like dementia, osteoporosis, diabetes, arthritis, cancer, and cardiovascular disease. However, some people who lived/live more than 100 years called 'Centenarians" and how do they achieve their extended lifespans are not completely understood. Studying these unknown factors of longevity is important not only to establish a longer human lifespan but also to manage and treat people with shortened lifespans suffering from age-related morbidities. Furthermore, older adults who maintain strong cognitive function are referred to as "SuperAgers" and may be resistant to risk factors linked to cognitive decline. Investigating the mechanisms underlying their cognitive resilience may contribute to the development of therapeutic strategies that support the preservation of cognitive function as people age. The key to a long, physically, and cognitively healthy life has been a mystery to scientists for ages. Developments in the medical sciences helps us to a better understanding of human physiological function and greater access to medical care has led us to an increase in life expectancy. Moreover, inheriting favorable genetic traits and adopting a healthy lifestyle play pivotal roles in promoting longer and healthier lives. Engaging in regular physical activity, maintaining a balanced diet, and avoiding harmful habits such as smoking contribute to overall well-being. The synergy between positive lifestyle choices, access to education, socio-economic factors, environmental determinants and genetic supremacy enhances the potential for a longer and healthier life. Our article aims to examine the factors associated with healthy ageing, particularly focusing on cognitive health in centenarians. We will also be discussing different aspects of ageing including genomic instability, metabolic burden, oxidative stress and inflammation, mitochondrial dysfunction, cellular senescence, immunosenescence, and sarcopenia.

The role of dietary fats on cognition and sarcopenia in the elderly

BACKGROUND AND OBJECTIVES

To elucidate the role of dietary fats on the relationship between mild cognitive impairment and sarcopenia and help identifying and preventing the decline of cognitive and muscle function in elderly individuals.

METHODS AND STUDY DESIGN

The study conducted involving a group of 1812 individuals between the ages of 61 and 92. Body composition and BMR were assessed by bioelectrical impedance analysis. Cognitive function and dietary nutrition were evaluated by neuropsychological assessments and questionnaire of food intake frequency. Lipidomics analysis was performed using UHPLC-Qtrap-MS/MS.

RESULTS

MCI and SA are mutual influencing factors, lower intake of MUFA, PUFA and higher intake of fat was associated with cognitive dysfunction and/or SA (p < 0.05). PUFA was important for MCI combined with SA (Compared with Q1, Q4 OR: 0.176, 95%CI: 0.058,0.533). Lipidomics analysis revealed that triacylglycerol (TAG) contain more carbon chains with saturated double bonds may be closely related to cognitive impairment and the progression of SA (p < 0.05). While, DAG with carbon chains of unsaturated double bonds is opposite.

CONCLUSIONS

Insufficient intake of unsaturated fatty acids was associated with the development of cognitive decline and the progression of SA. MUFA affecting muscle health, fats and PUFA has a greater impact on MCI combined with SA. Less MUFA intake and increasing saturated double-bonded fatty acid intake might be the key factors on promoting cognitive impairment and SA in the elderly. They have the potential to serve as prospective biomarkers indicating a higher risk of cognitive decline and/or SA in the elderly population.

Safeguarding vitality and cognition: The role of sarcopenia in intrinsic capacity decline among octogenarians from multiple cohorts

BACKGROUND

Sarcopenia and intrinsic capacity (IC) declines pose significant challenges to healthy aging, particularly in the rapidly growing octogenarian population. This study aimed to elucidate the relationship between sarcopenia and declines in IC across multiple cohorts of community-dwelling older adults.

METHODS

Data from four Taiwanese cohorts were analyzed. Sarcopenia was diagnosed based on the Asian Working Group for Sarcopenia (AWGS) 2019 criteria (algorithm 1: categorized as either having possible sarcopenia or not (robust); algorithm 2: categorized as robust, possible sarcopenia or sarcopenia). IC was operationalized using the World Health Organization's Integrated Care for Older People (ICOPE) framework (step 1 and step 2), encompassing six domains: locomotion, vitality, vision, hearing, cognition, and psychological well-being. Multivariable logistic regression models were adopted to assess the association between sarcopenia and IC decline.

RESULTS

Among 599 octogenarians (median age 82.2 years, 54.8% male), the prevalence of possible sarcopenia (algorithm 1) was 64.6%. When adopting algorithm 2, the prevalence of possible sarcopenia and sarcopenia was 46,2% and 32.1%, respectively. After adjusting for covariates, participants with possible sarcopenia or sarcopenia (algorithm 2) were more likely to exhibit declines in vitality (ICOPE Step 1: possible sarcopenia aOR 3.65, sarcopenia aOR 4.74; ICOPE Step 2: possible sarcopenia aOR 5.11, sarcopenia aOR 14.77) and cognition (ICOPE Step 1: possible sarcopenia aOR 2.40, sarcopenia aOR 2.12; ICOPE Step 2: possible sarcopenia aOR 2.02, sarcopenia aOR 2.51) compared to robust individuals.

CONCLUSIONS

This study underscores the robust association between sarcopenia and declines in vitality and cognition among octogenarians, highlighting the importance of sarcopenia screening and management in promoting healthy longevity in this vulnerable population.

Cognition as mediator of pulmonary function and risk of sarcopenia among older adults

BACKGROUND

The relationship between lung function and sarcopenia remains ambiguous. The primary aim of this study was to investigate the potential association between lung function and sarcopenia in the older adults, as well as to examine the mediating role of cognitive function in this relationship.

METHODS

The participants were selected from a nationally representative population-based cohort in China. The peak expiratory flow (PEF) measurement was used to evaluate the lung function in older persons. The sarcopenia was diagnosed using the guidelines of the Asian Working Group for Sarcopenia (AWGS) in 2019. The Cox proportional hazard model was utilized to perform primary analyses of the relationship between PEF and sarcopenia. The mediating effect of cognitive function was evaluated using the counterfactual mediation method.

RESULTS

This cohort study included 4,011 older adults (average age, 66.6 years; 53.3% males). During a follow-up period of 3.86 years, 349 individuals were diagnosed with sarcopenia. After adjusting for potential confounders, each one-standard-deviation increase in PEF was associated with a 28% reduction in the risk of sarcopenia (hazard ratio [HR]: 0.72; 95% confidence interval [CI]: 0.63, 0.80). There was a significant mediation of cognition for the association between PEF and incident sarcopenia, and the proportion mediated was 12.2% (95% CI: 4.5%, 23.1%).

CONCLUSIONS

Older adults with impaired lung function are more likely to develop sarcopenia. Nevertheless, cognition can explain only a small portion of this association. Thus, other potential pathways between lung function and sarcopenia must be elucidated.

[Convergent and discriminative validity of the Frail-VIG index with the Pfeiffer test in people cared for in home care]

INTRODUCTION

The Frail-VIG index-and the Pfeiffer test are measurements used in Primary Care for assessment frailty and the cognitive impairment screening. The Frail-VIG index is a multidimensional instrument that allows a rapid assessment of the degree of frailty in the context of clinical practice.

OBJECTIVE

Our aim was to investigate the convergent and discriminative validity of the Frail-VIG index with regard to Pfeiffer test value.

DESIGN

A cross-sectional study. SITE: Two urban Primary Health Care centres of the Catalan Institute of Health, Barcelona (Spain).

PARTICIPANTS

All people included under a home care programme during the year 2018. No exclusion criteria were applied.

MAIN MEASUREMENTS

We used the Frail-VIG index to measure frailty and the Pfeiffer test to cognitive impairment screening. Trained nurses administered both instruments during face-to-face assessments in a participant's home during usual care. The relationships between both instruments were examined using Pearson's correlation coefficient.

RESULTS

A total of 412 participants were included. Frail-VIG score and Pfeiffer test value were moderately correlated (r=0.564; P<0.001). Non-frail people had a lower risk of developing cognitive impairment than moderate to severe frail people. The value of the Pfeiffer test increased significantly as the Frail-VIG index score also increased.

CONCLUSIONS

Frail-VIG index demonstrated a convergent validity with the Pfeiffer test. Its discriminative validity was optimal, as their scores showed an excellent capacity to differentiate between people with a higher and lower risk of developing cognitive impairment. These findings provide additional pieces of evidence for construct validity of the Frail-VIG index.

Association of low muscle mass with cognitive function and mortality in USA seniors: results from NHANES 1999-2002

BACKGROUND

Sarcopenia and cognitive impairment have been linked in prior research, and both are linked to an increased risk of mortality in the general population. Muscle mass is a key factor in the diagnosis of sarcopenia. The relationship between low muscle mass and cognitive function in the aged population, and their combined impact on the risk of death in older adults, is currently unknown. This study aimed to explore the correlation between low muscle mass and cognitive function in the older population, and the relationship between the two and mortality in older people.

METHODS

Data were from the National Health and Nutrition Examination Survey 1999-2002. A total of 2540 older adults aged 60 and older with body composition measures were included. Specifically, 17-21 years of follow-up were conducted on every participant. Low muscle mass was defined using the Foundation for the National Institute of Health and the Asian Working Group for Sarcopenia definitions: appendicular lean mass (ALM) (< 19.75 kg for males; <15.02 kg for females); or ALM divided by body mass index (BMI) (ALM: BMI, < 0.789 for males; <0.512 for females); or appendicular skeletal muscle mass index (ASMI) (< 7.0 kg/m2 for males; <5.4 kg/m2 for females). Cognitive functioning was assessed by the Digit Symbol Substitution Test (DSST). The follow-up period was calculated from the NHANES interview date to the date of death or censoring (December 31, 2019).

RESULTS

We identified 2540 subjects. The mean age was 70.43 years (43.3% male). Age-related declines in DSST scores were observed. People with low muscle mass showed lower DSST scores than people with normal muscle mass across all age groups, especially in the group with low muscle mass characterized by ALM: BMI (60-69 years: p < 0.001; 70-79 years: p < 0.001; 80 + years: p = 0.009). Low muscle mass was significantly associated with lower DSST scores after adjusting for covariates (ALM: 43.56 ± 18.36 vs. 47.56 ± 17.44, p < 0.001; ALM: BMI: 39.88 ± 17.51 vs. 47.70 ± 17.51, p < 0.001; ASMI: 41.07 ± 17.89 vs. 47.42 ± 17.55, p < 0.001). At a mean long-term follow-up of 157.8 months, those with low muscle mass were associated with higher all-cause mortality (ALM: OR 1.460, 95% CI 1.456-1.463; ALM: BMI: OR 1.452, 95% CI 1.448-1.457); ASMI: OR 3.075, 95% CI 3.063-3.088). In the ALM: BMI and ASMI-defined low muscle mass groups, participants with low muscle mass and lower DSST scores were more likely to incur all-cause mortality ( ALM: BMI: OR 0.972, 95% CI 0.972-0.972; ASMI: OR 0.957, 95% CI 0.956-0.957).

CONCLUSIONS

Low muscle mass and cognitive function impairment are significantly correlated in the older population. Additionally, low muscle mass and low DSST score, alone or in combination, could be risk factors for mortality in older adults.

Nutrition intake modifies the association between pulmonary function and cognitive performance among elderly Americans from NHANES 2011-2012

PURPOSE

Nutrition intake is one of the modifiable risk factors for cognitive decline. Whether energy and protein intakes alter the association between pulmonary function (PF) and cognition has not been studied.

METHODS

We made use of information from the U.S. National Health and Nutrition Examination Survey (NHANES) 2011-2012. PF measures, including forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and peak expiratory flow (PEF), were calculated, whereas cognitive function was assessed through four tests: the Immediate Recall test (IRT), the Delayed Recall test (DRT), the Animal Fluency test (AFT) and the Digit Symbol Substitution test (DSST). Energy and protein intakes were measured using the 24-h dietary recall method. Weighted generalized linear regression was performed upon adjustment for covariates. Further interaction analyses were conducted to investigate the effect of energy and protein intakes on the association between PF and cognition.

RESULTS

We finally included 803 participants aged ≥ 60 years (54.4% female, weighted value). After adjusting for covariates, multiple measures (including FEV1, FVC, PEF, and composite PF) were all positively associated with better global cognition and the DSST score (P < 0.05). A stronger positive association between the DSST score and FEV1 (P for interaction = 0.001), FVC (P for interaction = 0.004), PEF (P for interaction = 0.003), and composite PF (P for interaction = 0.001) in lower energy intake. Similar results were observed in lower protein intake (all P for interaction < 0.05).

CONCLUSION

Higher PF was independently associated with improved specific components of cognitive function (i.e., the DSST score). The positive association between PF and the DSST score was stronger in individuals with lower energy and protein intakes.

Sarcopenia using muscle mass prediction model and cognitive impairment: A longitudinal analysis from the English longitudinal study on ageing

BACKGROUND

Literature on the association between sarcopenia and cognitive impairment is largely unclear and mainly limited to non-European populations. Therefore, the aim of this study is to explore if the presence of sarcopenia at the baseline could increase the risk of cognitive impairment in a large cohort of older people participating to the English Longitudinal Study of Ageing (ELSA), over ten years of follow-up.

METHODS

Sarcopenia was diagnosed as having low handgrip strength and low skeletal muscle mass index at the baseline, using a muscle mass prediction model; cognitive function was evaluated in the ELSA through several tests. The results are reported in the whole sample adjusted for potential baseline confounders and after matching sarcopenic and non-sarcopenic participants with a propensity score.

RESULTS

2738 people (mean age: 68.7 years, 54.4% males) were included. During the ten years of follow-up, sarcopenia was associated with significantly lower scores in memory (p < 0.001), verbal fluency (p < 0.001), immediate word recall (p <0.001), delayed word recall (p = 0.018), and in recall summary score (p < 0.001). After adjusting for eight potential confounders, the presence of sarcopenia was significantly associated with poor verbal fluency (odds ratio, OR= 1.417, 95% confidence intervals, CI= 1.181-1.700) and in propensity-score matched analyses (OR=1.272, 95%CI= 1.071- 1.511).

CONCLUSIONS AND IMPLICATIONS

Sarcopenia was found to be associated with a significantly higher incidence of poor cognitive status in a large population of elderly people followed up for 10 years, suggesting it may be an important potential risk factor for dementia.

The prevalence and factors associated with sarcopenia in Thai older adults: A systematic review and meta-analysis

Objective

This systematic review and meta-analysis aimed to assess the prevalence and identify factors associated with sarcopenia in older Thais.

Methods

Research studies were searched in online databases, including PubMed, Embase, Scopus, and Thai-Journal Citation Index. The articles included in this review were limited to being published between January 1, 2013 and January 31, 2023 and observational study designs. The research quality was evaluated using the Joanna Briggs Institute (JBI) critical appraisal tool for prevalence studies. A meta-analysis was performed using the JBI SUMARI software. The review protocol has been registered on PROSPERO with the assigned ID CRD42023420514.

Results

A total of 265 research articles were initially identified, out of which 17 articles were included in this study, including a total of 4,668 participants aged 60 years and over, consisting of 1,380 (29.6%) men and 3,288 (70.4%) women. The overall prevalence of sarcopenia in Thai older adults was 20.7% (95% CI 14.4%-27.8%). Subgroup analysis of the sarcopenia prevalence based on the study areas revealed that the prevalence was 33.4% (95% CI 28.7%-38.3%) in hospitalized individuals, 23.2% (95% CI 12.5%-35.9%) in outpatient clinic settings, and 17.3% (95% CI 9.4%-26.8%) in community-living older adults. Advanced age (OR = 4.60, 95% CI 3.07-6.91), being male (OR = 2.30, 95% CI 1.37-3.85), low body mass index (BMI) (OR = 8.95, 95% CI 6.05-13.25), and malnutrition (OR = 2.78, 95% CI 2.09-3.70) are strong predictors of sarcopenia in older adults in Thailand.

Conclusions

This systematic review represents the first assessment of the overall prevalence and factors associated with sarcopenia in Thai older adults, indicating its significant concern within this population. These findings are of importance for public health management aimed at preventing and managing sarcopenia in the country.

The longitudinal bidirectional association between sarcopenia and cognitive function in community-dwelling older adults: Findings from the China Health and Retirement Longitudinal Study

Background

Although an association between sarcopenia and cognitive function has been demonstrated, the directional association remains unclear. The present study aimed to evaluate the longitudinal reciprocal relationship and identify the possible temporal sequence between sarcopenia and cognitive function in older Chinese adults.

Methods

Data were collected from the China Health and Retirement Longitudinal Study (CHARLS) baseline survey in 2011 and the follow-up survey in 2015. Cognitive function was measured by episodic memory and executive function. Sarcopenia status (non-sarcopenia, possible sarcopenia and sarcopenia) was defined based on the Asian Working Group for Sarcopenia 2019 criteria. Linear regression analysis and ordinal logistic regression analysis were employed to investigate the relationship between baseline sarcopenia status and follow-up cognition, as well as the association of baseline cognition with follow-up sarcopenia status, respectively. A cross-lagged panel analysis was performed to simultaneously evaluate the bidirectional association and the strength of the temporal relationship.

Results

Of 2689 participants, the median age was 65.0 years and 1249 (46.5%) were female. After adjusting for potential confounders and baseline measurements, baseline sarcopenia status was dose-dependently associated with subsequent cognitive scores (β = -0.45; P for trend = 0.001), and baseline cognitive scores (in tertiles) were also dose-dependently associated with subsequent sarcopenia status (odds ratio (OR) = 0.86; P for trend = 0.017). The cross-lagged panel analysis indicated that the standardised effect size of sarcopenia status on cognitive function (β = -0.09; P < 0.001) is larger relative to the effect of cognitive function on sarcopenia status (β = -0.05; P = 0.019).

Conclusions

There is a longitudinal, bidirectional relationship between sarcopenia status and cognitive function in older Chinese adults. Sarcopenia is likely the driving force in these dynamic associations. These findings imply that interventions in either sarcopenia or cognitive decline may have the ability to generate reciprocal benefits over time. More research is warranted to confirm these findings and to further elucidate underlying causal pathways.

Sarcopenia and diabetes-induced dementia risk

This study aimed to investigate whether sarcopenia independently increases the risk of diabetes-induced dementia in elderly individuals diagnosed with type 2 diabetes mellitus. The study cohort consisted of a large sample of elderly individuals aged 60 years and above, who were diagnosed with type 2 diabetes mellitus between 2008 and 2018. To minimize potential bias and achieve covariate balance between the sarcopenia and non-sarcopenia groups, we employed propensity score matching. Various statistical analyses, including Cox regression models to assess dementia risk and associations, competing risk analysis to account for mortality and Poisson regression analysis for incidence rates, were used. Before propensity score matching, the study included 406 573 elderly type 2 diabetes mellitus patients, with 20 674 in the sarcopenia group. Following propensity score matching, the analysis included a total of 41 294 individuals, with 20 647 in the sarcopenia group and 20 647 in the non-sarcopenia group. Prior to propensity score matching, elderly type 2 diabetes mellitus patients with sarcopenia exhibited a significantly higher risk of dementia (adjusted hazard ratio: 1.12, 95% confidence interval: 1.07-1.17). After propensity score matching, the risk remained significant (adjusted hazard ratio: 1.14, 95% confidence interval: 1.07-1.21). Incidence rates of dementia were notably higher in the sarcopenia group both before and after propensity score matching, underscoring the importance of sarcopenia as an independent risk factor. Our study highlights sarcopenia as an independent risk factor for diabetes-induced dementia in elderly type 2 diabetes mellitus patients. Advanced age, female gender, lower income levels, rural residency, higher adapted diabetes complication severity index and Charlson Comorbidity Index scores and various comorbidities were associated with increased dementia risk. Notably, the use of statins was linked to a reduced risk of dementia. This research underscores the need to identify and address modifiable risk factors for dementia in elderly type 2 diabetes mellitus patients, offering valuable insights for targeted interventions and healthcare policies.

Knowledge mapping of exercise and physical activity research in older adults: Hotspots, bursts, and trends of the last decade

Background and objectives

Global aging has increased the importance of health management in older adults. Exercise is a crucial strategy for healthy aging and has led to numerous scientific advancements due to its impact on age-related illnesses. We aim to investigate the research hotspots, bursts of knowledge base, and trends in the field of exercise and physical activity in older adults over the past decade and present them in a visual manner.

Methods

We searched and retrieved data from the Web of Science database, and performed a bibliometric analysis of publications on exercise and physical activity research in older adults from 2013 to 2022. We evaluated the current status and hotspots through co-occurrence analysis using VOSviewer. The evolution and bursts of knowledge base were assessed through co-citation analysis using CiteSpace. Thematic evolution was analyzed using the bibliometrix package to discover keyword trends. The attribution and collaboration of countries/regions, institutions and authors were also analyzed.

Results

A total of 27,820 publications were included. Publications on exercise and physical activity in older adults increased from 1755 records in 2013-3737 records in 2022 annually. In co-occurrence analysis of keywords, 5 major clusters were revealed: sarcopenia, cognition, frailty, mental health, and rehabilitation. Co-citation analysis reveals that the knowledge base has evolved from references focused on frailty, dementia, and physical activity before 2016 to references focus on sarcopenia, cognition and sedentary behavior after 2020. Among the top 10 high-frequency keywords, sarcopenia demonstrated a consistent and significant upward trend, with its percentage increasing from 8.7 % (82 times) in 2016 to 12.2 % (236 times) in the most recent year, making it the most frequently used keyword. Frailty ranked second, starting at 5.6 % (41 times) in 2013 and gradually rising to 11.7 % (225 times) in 2022. The most productive country, institution and author were the USA (8212 publications), the University of Pittsburgh(501 publications), and Brendon Stubbs(94 publications), respectively.

Discussion

Publications on exercise and physical activity for older adults have surged in the last decade, accompanied by a shift in the knowledge base. Regional disparities in the academic output in this field need to be addressed in the future to promote healthy aging.

Physical Activity Mediates the Relationship Between Sarcopenia and Cognitive Function Among Older Adults in Nursing Homes

Purpose

Sarcopenia and physical activity are significant factors influencing cognitive function. However, few studies have examined their underlying mechanisms between the three conditions. The aim of the study is to examine the mediating role of physical activity in the relationship between sarcopenia and cognitive function in elderly nursing home residents.

Materials and Methods

A total of 420 older adults aged 60 years and above in nursing homes participated in this study. Sarcopenia was defined following the Asian Sarcopenia Working Group (AWGS) 2019 criteria. Cognitive function was assessed by the Mini-Mental State Examination (MMSE). Multiple linear regression analysis was employed to explore the relationships between sarcopenia, cognitive function and physical activity. Mediation analyses were performed to examine whether physical activity moderates the relationship between sarcopenia and cognitive function, with the use of PROCESS macro version 4.0.

Results

A total of 386 older adults were included in the analysis (mean age 80.30 years), 175 (45.3%) were assessed as cognitive impairment, and sarcopenia was more common in those with cognitive impairment (p < 0.01). The linear regression analysis indicated that there were significant associations between sarcopenia and physical activity (β = -0.285, p = 0.012), physical activity and cognitive function (β = 0.218, p < 0.001), and sarcopenia and cognitive function (β = -0.245, p = 0.021). Mediating effects of physical activity on the association between sarcopenia and cognitive function were observed in participants, with 20.2% of partial mediating effect.

Conclusion

The results of the study suggest physical activity may partially buffer the adverse effects of sarcopenia on cognitive impairment among the older adults in nursing homes. Accordingly, engagement in physical activity can help to preserve cognitive function among those with sarcopenia.

Alzheimer's disease with frailty: Prevalence, screening, assessment, intervention strategies and challenges

Alzheimer's disease (AD) is a neurodegenerative disorder that affects millions worldwide and is expected to surge in prevalence due to aging populations. Frailty, characterized by muscle function decline, becomes more prevalent with age, imposing substantial burdens on patients and caregivers. This paper aimed to comprehensively review the current literature on AD coupled with frailty, encompassing prevalence, screening, assessment, and treatment while delving into the field's challenges and future trajectories. Frailty and AD coexist in more than 30% of cases, with hazard ratios above 120% indicating a mutually detrimental association.Various screening tools have emerged for both frailty and AD, including the Fried Frailty Phenotype (FP), FRAIL scale, Edmonton Frailty Scale (EFS), Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Clock Drawing Test (CDT), and General Practitioner Assessment of Cognition (GPCOG). However, none has solidified its role as the definitive gold standard. The convergence of electronic health records and brain aging biomarkers heralds a new era in AD with frailty screening and assessment. In terms of intervention, non-pharmacological strategies spanning nutrition, horticulture, exercise, and social interaction, along with pharmacological approaches involving acetylcholinesterase inhibitors (AChEIs), N-methyl-D-aspartate (NMDA) receptor antagonists, and anti-amyloid beta-protein medications, constituted cornerstones for treating AD coupled with frailty. Technological interventions like repetitive transcranial magnetic stimulation (rTMS) also entered the fold. Notably, multi-domain non-pharmacological interventions wield considerable potential in enhancing cognition and mitigating disability. However, the long-term efficacy and safety of pharmacological interventions necessitate further validation. Diagnosing and managing AD with frailty present several daunting challenges, encompassing low rates of early co-diagnosis, limited clinical trial evidence, and scarce integrated, pioneering service delivery models. These challenges demand heightened attention through robust research and pragmatic implementation.

The association between regional adiposity, cognitive function, and dementia-related brain changes: a systematic review

Background

Adiposity has been previously associated with cognitive impairment and Alzheimer's disease and related disorders (ADRD). Body mass index (BMI) is the most common measure of global adiposity, but inconsistent results were found since it is a global measurement. BMI does not represent regional fat distribution which differs between sexes, race, and age. Regional fat distribution may contribute differently to cognitive decline and Alzheimer's disease (AD)-related brain changes. Fat-specific targeted therapies could lead to personalized improvement of cognition. The goal of this systematic review is to explore whether regional fat depots, rather than central obesity, should be used to understand the mechanism underlying the association between adiposity and brain.

Methods

This systematic review included 33 studies in the English language, conducted in humans aged 18 years and over with assessment of regional adiposity, cognitive function, dementia, and brain measures. We included only studies that have assessed regional adiposity using imaging technics and excluded studies that were review articles, abstract only or letters to editor. Studies on children and adolescents, animal studies, and studies of patients with gastrointestinal diseases were excluded. PubMed, PsychInfo and web of science were used as electronic databases for literature search until November 2022.

Results

Based on the currently available literature, the findings suggest that different regional fat depots are likely associated with increased risk of cognitive impairment, brain changes and dementia, especially AD. However, different regional fat depots can have different cognitive outcomes and affect the brain differently. Visceral adipose tissue (VAT) was the most studied regional fat, along with liver fat through non-alcoholic fatty liver disease (NAFLD). Pancreatic fat was the least studied regional fat.

Conclusion

Regional adiposity, which is modifiable, may explain discrepancies in associations of global adiposity, brain, and cognition. Specific regional fat depots lead to abnormal secretion of adipose factors which in turn may penetrate the blood brain barrier leading to brain damage and to cognitive decline.

Association between masseter muscle volume, nutritional status, and cognitive status in older people

OBJECTIVES

Clinical evidence has suggested that oral function is associated with cognitive, physical, and nutritional status of older people. A smaller volume of masseter, a crucial muscle for mastication, was associated with frailty. It has remained unknown if smaller masseter is associated with cognitive impairment. The current study investigated the association between masseter muscle volume, nutritional status, and cognitive status in older people.

MATERIALS AND METHODS

We recruited 19 patients with mild cognitive impairment (MCI), 15 patients with Alzheimer's disease (AD), and 28 sex and age-matched non-cognitive impairment (non-CI) older subjects. The number of missing teeth (NMT), masticatory performance (MP), maximal hand-grip force (MGF), and calf circumference (CC) were assessed. The masseter volume index (MVI) was calculated based on the masseter volume measured using magnetic resonance imaging.

RESULTS

The MVI was significantly lower in the AD group, compared to the MCI as well as the non-CI group. Multiple regression analyses revealed that the MVI was significantly associated with nutritional status (as indexed by CC) in the analysis of combination of NMT, MP, and the MVI. Moreover, the MVI was a significant predictor of CC only in patients with cognitive impairment (i.e., MCI+AD) but not in the non-CI group.

CONCLUSIONS

Our findings suggested that in addition to the NMT and MP, masseter volume is a critical oral factor associated with cognitive impairment.

CLINICAL RELEVANCE

Reduction of MVI should be carefully monitored for patients with dementia and frailty, to whom a lower MVI may indicate worse nutrient intake.

Sarcopenia Screened with SARC-F and Subjective Memory Complaints Are Independently Associated with Increased Risk of Incident Dementia among Cognitively Unimpaired Older Adults

OBJECTIVES

The main aim of this study was to examine the association of sarcopenia and subjective memory complaints with the incidence of dementia in a population-based cohort of cognitively unimpaired older adults.

DESIGN

Three-year longitudinal study.

SETTINGS AND PARTICIPANTS

A total of 2163 community-dwelling persons aged 65 years or older who participated in the National Health Interview Survey in Taiwan, 2017.

MEASUREMENTS

Sarcopenia was determined based on SARC-F, a self-reported symptom-based questionnaire that includes five components: strength, assistance walking, rise from a chair, climb stairs, and falls. Two questions ("Do you have difficulties with your memory or attention?" and "Do you have difficulties with your memory only or attention only or both?") were used to screen for subjective memory complaints (SMCs). The incidence of dementia was determined by data linkage to the Taiwan National Health Insurance claims database from 2018 to 2020.

RESULTS

Among the 2163 participants without dementia at baseline, 135 had incident dementia during the 3-year follow-up, giving a crude incidence rate of 6.2% (135/2163). Compared to participants free from sarcopenia and SMCs, the adjusted hazard ratio for incident dementia was 1.83 (95% confidence interval [CI]: 1.23-2.72) for SMCs alone, 2.40 (95% CI: 1.17-4.93) for sarcopenia alone, and 2.49 (95% CI: 1.21-5.11) for coexisting SMCs and sarcopenia.

CONCLUSIONS

Our results indicate that sarcopenia screened with SARC-F and SMCs independently predict the cognitively unimpaired older adults at risk of incident dementia. Our findings highlight the importance of screening not only for cognitive but also muscle deficits to identify those at increased risk of incident dementia.

Relationship between Social Support, Sarcopenia, and Cognitive Impairment in Chinese Community-Dwelling Older Adults

BACKGROUND

Cognitive impairment and sarcopenia have become important challenges for the growing aging population. Social support has been shown to protect against cognitive impairment, but its impact on sarcopenia remains unknown. The purpose of this study was to explore the correlation between social support, sarcopenia, and cognitive impairment in Chinese older adults.

METHOD

A multi-stage whole group sampling method was used to conduct a cross-sectional survey of 720 community-dwelling older people in Shanghai. The definition of sarcopenia was in accordance with the criteria of the Asian Working Group for Sarcopenia (AWGS) 2019. Cognitive impairment was evaluated using a computerized neuropsychological assessment device that had been previously validated. Social support was assessed using the Social Support Rate Scale. Logistic regression analyses were conducted to explore the relationship between social support cognitive impairment and sarcopenia, fully adjusting for all potential confounding factors.

RESULTS

Our study found that 230 (31.94%) of the participants had cognitive impairment and 97 (13.47%) of the participants had sarcopenia. The mean social support score was 35.10 ± 7.54. Besides, the results showed that cognitive impairment was associated with sarcopenia (OR:1.650, 95% CI: 1.048, 2.596, P=0.030) after adjusting for confounding factors. Older adults with high level social support had the lowest risk of cognitive impairment (OR: 0.297, 95% CI: 0.115, 0.680, P=0.021) and sarcopenia (OR: 0.113, 95% CI: 0.031, 0.407, P=0.001), respectively.

CONCLUSION

Our analysis revealed that high level social support was negatively associated with sarcopenia and cognitive impairment. These findings provide strong support for the health promotion effect of social networks against sarcopenia and cognitive impairment in Chinese community-dwelling older adults, with important implications for healthcare policy makers.