Plasma fatty acid biomarkers are associated with gait speed in community-dwelling older adults: The Three-City-Bordeaux study

Overfeeding polyunsaturated fat compared with saturated fat does not differentially influence lean tissue accumulation in individuals with overweight: a randomized controlled trial

BACKGROUND

Fatty acids may influence lean tissue volume and skeletal muscle function. We previously reported in young lean participants that overfeeding PUFA compared with SFA induced greater lean tissue accumulation despite similar weight gain.

OBJECTIVES

In a double-blind randomized controlled trial, we aimed to investigate if the differential effects of overfeeding SFA and PUFA on lean tissue accumulation could be replicated in individuals with overweight and identify potential determinants. Further, using substitution models, we investigated associations between SFA and PUFA concentrations with lean tissue volume in a large population-based sample (UK Biobank).

METHODS

Sixty-one males and females with overweight [BMI (kg/m2): 27.3 (interquartile range (IQR), 25.4-29.3); age: 43 (IQR, 36-48)] were overfed SFA (palm oil) or n-6 (ω-6) PUFA (sunflower oil) for 8 wk. Lean tissue was assessed by MRI. We had access to n = 13,849 participants with data on diet, covariates, and MRI measurements of lean tissue, as well as 9119 participants with data on circulating fatty acids in the UK Biobank.

RESULTS

Body weight gain mean (SD) was similar in PUFA (2.01 ± 1.90 kg) and SFA (2.31 ± 1.38 kg) groups. Lean tissue increased to a similar extent [0.54 ± 0.93 L and 0.67 ± 1.21 L for PUFA and SFA groups, respectively, with a difference between groups of 0.07 (-0.21, 0.35)]. We observed no differential effects on circulating amino acids, myostatin, or IL-15 and no clear determinants of lean tissue accumulation. Similar nonsignificant results for SFA and PUFA were observed in UK Biobank, but circulating fatty acids demonstrated ambiguous and sex-dependent associations.

CONCLUSIONS

Overfeeding SFA or PUFA does not differentially affect lean tissue accumulation during 8 wk in individuals with overweight. A lack of dietary fat type-specific effects on lean tissue is supported by specified substitution models in a large population-based cohort consuming their habitual diet. This trial was registered at clinicaltrials.gov identifier as NCT02211612.

Omega-3 polyunsatured fatty acids and physical performance across the lifespan: a narrative review

Background and Aims

Physical performance is a major contributor of mobility and independence during older life. Despite a progressive decline in musculoskeletal function starts from middle age, several factors acting during the life-course can negatively influence musculoskeletal functional capacities. Lifestyle interventions incorporating nutrition and physical exercise can help maximizing the muscle functional capacities in early life as well as preserving them later in life. Among various dietary compounds, omega-3 polyunsaturated fatty acids (PUFAs) are gaining growing attention for their potential effects on muscle membrane composition and muscle function. Indeed, several pathways are enhanced, such as an attenuation of pro-inflammatory oxidative stress, mitochondrial function, activation of the mammalian target of rapamycin (mTOR) signaling and reduction of insulin resistance.

Methods

We performed a narrative review to explore the existing literature on the relationship between omega-3 PUFAs and physical performance across the life-course.

Results

Growing evidence from randomized controlled trials (RCTs) suggests beneficial effects of omega-3 PUFAs on muscle function, including physical performance parameters in mid to later life. On the other hand, despite a direct association in early life is not available in literature, some mechanisms by which omega-3 PUFAs may contribute to improved adult physical performance could be hypothesized.

Conclusion

Omega-3 PUFAs are gaining growing attention for their positive effect on muscle function parameters. The integration of physical function measures in future studies would be of great interest to explore whether omega-3 PUFAs could contribute to improved muscle function, starting from early life and extending throughout the lifespan. However, larger and high-quality RCTs are needed to fully elucidate the beneficial effects of omega-3 PUFAs supplementation on muscle mass and function.

Shared plasma metabolomic profiles of cognitive and mobility decline predict future dementia

Experiencing decline in both cognition and mobility is associated with a substantially higher dementia risk than cognitive decline only. Metabolites associated with both cognitive and mobility declines may be early predictors of dementia and reveal specific pathways to dementia. We analyzed data from 2450 participants initially free of dementia who had 613 metabolites measured in plasma in 1998-1999 (mean age = 75.2 ± 2.9 years old, 37.8% Black, 50% women) from the Health, Aging and Body Composition study. Dementia diagnosis was determined by race-specific decline in 3MS scores, medication use, and hospital records through 2014. Cognition and mobility were repeatedly measured using 3MS and a 20-m walking test up to 10 years, respectively. We examined metabolite associations with changes in 3MS (n = 2046) and gait speed (n = 2019) using multivariable linear regression adjusted for age, sex, race, and baseline performance and examined metabolite associations with dementia risk using Cox regression. During a mean follow-up of 9.3 years, 534 (21.8%) participants developed dementia. On average, 3MS declined 0.47/year and gait declined 0.04 m/sec/year. After covariate adjustment, 75 metabolites were associated with cognitive decline, and 111 metabolites were associated with gait decline (FDR-adjusted p < 0.05). Twenty-six metabolites were associated with both cognitive and gait declines. Eighteen of 26 metabolites were associated with dementia risk (p < 0.05), notably amino acids, glycerophospholipids (lysoPCs, PCs, PEs), and sphingolipids. Results remained similar after adjusting for cardiovascular disease or apolipoprotein E ɛ4 carrier status. During aging, metabolomic profiles of cognitive decline and mobility decline show distinct and shared signatures. Shared metabolomic profiles suggest that inflammation and deficits in mitochondria and the urea cycle in addition to the central nervous system may play key roles in both cognitive and mobility declines and predict dementia. Future studies are warranted to investigate longitudinal metabolite changes and metabolomic markers with dementia pathologies.

Nutrition as the foundation for successful aging: a focus on dietary protein and omega-3 polyunsaturated fatty acids

Skeletal muscle plays a critical role throughout the aging process. People living with sarcopenia, a progressive and generalized loss of skeletal muscle mass and function, often experience diminished quality of life, which can be attributed to a long period of decline and disability. Therefore, it is important to identify modifiable factors that preserve skeletal muscle and promote successful aging (SA). In this review, SA was defined as (1) low cardiometabolic risk, (2) preservation of physical function, and (3) positive state of wellbeing, with nutrition as an integral component. Several studies identify nutrition, specifically high-quality protein (eg, containing all essential amino acids), and long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), as positive regulators of SA. Recently, an additive anabolic effect of protein and n-3 PUFAs has been identified in skeletal muscle of older adults. Evidence further suggests that the additive effect of protein and n-3 PUFAs may project beyond skeletal muscle anabolism and promote SA. The key mechanism(s) behind the enhanced effects of intake of protein and n-3 PUFAs needs to be defined. The first objective of this review is to evaluate skeletal muscle as a driver of cardiometabolic health, physical function, and wellbeing to promote SA. The second objective is to examine observational and interventional evidence of protein and n-3 PUFAs on skeletal muscle to promote SA. The final objective is to propose mechanisms by which combined optimal intake of high-quality protein and n-3 PUFAs likely play a key role in SA. Current evidence suggests that increased intake of protein above the Recommended Dietary Allowance and n-3 PUFAs above the Dietary Guidelines for Americans recommendations for late middle-aged and older adults is required to maintain skeletal muscle mass and to promote SA, potentially through the mechanistical target of rapamycin complex 1 (mTORC1).

Causal associations of plasma omega-3 polyunsaturated fatty acids with sarcopenia-related traits: a two-sample Mendelian randomization study

OBJECTIVE

To evaluate the causal effect of plasma omega-3 polyunsaturated fatty acids (PUFAs) on sarcopenia-related traits (lean mass, grip strength and walking pace) utilizing two-sample Mendelian randomization (MR) approach.

METHODS

Based on genome-wide association study (GWAS) summary statistics, we performed two-sample MR applying the inverse variance weighted (IVW) as the primary method, supplemented with four additional sensitivity analyses. Furthermore, multivariable MR (MVMR) was applied to assess these associations independent of alcohol drinking, type 2 diabetes (T2D), triglycerides (TG), estimated glomerular filtration rate (eGFR) and C-reactive protein (CRP).

RESULTS

In univariable MR, the IVW analysis suggested no significant causal effect of genetically determined plasma omega-3 PUFAs on fat-free mass (right leg: β = 0.01, 95% CI = -0.02 to 0.05, P = 0.375; left leg: β = 0.01, 95% CI = -0.02 to 0.04, P = 0.446; right arm: β = 0.01, 95% CI = -0.02 to 0.05, P = 0.376; left arm: β = 0.01, 95% CI = -0.02 to 0.04, P = 0.384; trunk:β = 0.02, 95% CI = -0.02 to 0.06, P = 0.283; whole: β = 0.01, 95% CI = -0.03 to 0.04, P = 0.631), grip strength (right hand: β = -0.01, 95% CI = -0.03 to 0.01, P = 0.387; left hand: β = -0.01, 95% CI = -0.02 to 0.01, P = 0.553) and walking pace (β = 0.00, 95% CI = -0.01 to 0.02, P = 0.575), and sensitive analysis generated similar non-significant results. Furthermore, the MVMR revealed no independent causal association.

CONCLUSIONS

Genetically determined plasma omega-3 PUFAs have no causal effect on sarcopenia-related traits.

Fish Oil Supplementation with Resistance Exercise Training Enhances Physical Function and Cardiometabolic Health in Postmenopausal Women

Menopause is a condition associated with an increased risk of dysregulation in cardiovascular and metabolic health among older women. While fish oil (FO) has garnered great attention for its health-enhancing properties, its potential for enhancing cardiometabolic health in this demographic remains to be established. The purpose of this study was to determine the clinical efficacy of an 8 wk administration of FO combined with programmed resistance exercise training (RET) on physical function and risk factors associated with cardiometabolic health in healthy older women. Twenty, healthy, older women were randomly assigned to one of the two experimental groups: resistance training with placebo (RET-PL) or RET with fish oil (RET-FO). Physical function, blood pressure (BP), triglyceride (TG), and systemic inflammation and oxidative stress biomarkers were assessed before and after the intervention. Statistical significance was set at p ≤ 0.05. Physical function was greatly enhanced in both RET and RET-FO. Handgrip strength substantially increased only in RET-FO. RET-FO exhibited significant decreases in BP, TG, inflammatory cytokines (TNF-α and IL-6), and oxidative stress (MDA and 8-OHdG) levels, while no detectable changes were found in RET-PL. Our findings indicate that FO administration during 8 wks of RET appears to enhance muscle function and lower risk factors linked to cardiometabolic disorders in postmenopausal women.

Protectin DX as a therapeutic strategy against frailty in mice

Frailty in aging is driven by the dysregulation of multiple biological pathways. Protectin DX (PDX) is a docosahexaenoic acid (DHA)-derived molecule that alleviates many chronic inflammatory disorders, but its potential effects on frailty remain unknown. Our goal is to identify age-related impairments in metabolic systems and to evaluate the therapeutic potential of PDX on frailty, physical performance, and health parameters. A set of 22-month-old C57BL/6 male and female mice were assigned to vehicle (Old) or PDX daily gavage treatment for 9 weeks, whereas 6-month-old (Adult) mice received only vehicle. Forelimb and hindlimb strength, endurance, voluntary wheel activity and walking speed determined physical performance and were combined with a frailty index score and body weight loss to determine frailty status. Our data shows that old vehicle-treated mice from both sexes had body weight loss paralleling visceromegaly, and Old females also had impaired insulin clearance as compared to the Adult group. Aging was associated with physical performance decline together with higher odds of frailty development. There was also age-driven mesangial expansion and glomerular hypertrophy as well as bone mineral density loss. All of the in vivo and in vitro impairments observed with aging co-occurred with upregulation of inflammatory pathways and Myc signaling as well as downregulation of genes related to adipogenesis and oxidative phosphorylation in liver. PDX attenuated the age-driven physical performance (strength, exhaustion, walking speed) decline, promoted robustness, prevented bone losses and partially reversed changes in hepatic expression of Myc targets and metabolic genes. In conclusion, our data provides evidence of the beneficial therapeutic effect of PDX against features of frailty in mice. Further studies are warranted to investigate the mechanisms of action and the potential for human translation.

Dietary profiling of physical frailty in older age phenotypes using a machine learning approach: the Salus in Apulia Study

PURPOSE

Growing awareness of the biological and clinical value of nutrition in frailty settings calls for further efforts to investigate dietary gaps to act sooner to achieve focused management of aging populations. We cross-sectionally examined the eating habits of an older Mediterranean population to profile dietary features most associated with physical frailty.

METHODS

Clinical and physical examination, routine biomarkers, medical history, and anthropometry were analyzed in 1502 older adults (65 +). CHS criteria were applied to classify physical frailty, and a validated Food Frequency Questionnaire to assess diet. The population was subdivided by physical frailty status (frail or non-frail). Raw and adjusted logistic regression models were applied to three clusters of dietary variables (food groups, macronutrients, and micronutrients), previously selected by a LASSO approach to better predict diet-related frailty determinants.

RESULTS

A lower consumption of wine (OR 0.998, 95% CI 0.997-0.999) and coffee (OR 0.994, 95% CI 0.989-0.999), as well as a cluster of macro and micronutrients led by PUFAs (OR 0.939, 95% CI 0.896-0.991), zinc (OR 0.977, 95% CI 0.952-0.998), and coumarins (OR 0.631, 95% CI 0.431-0.971), was predictive of non-frailty, but higher legumes intake (OR 1.005, 95%CI 1.000-1.009) of physical frailty, regardless of age, gender, and education level.

CONCLUSIONS

Higher consumption of coffee and wine, as well as PUFAs, zinc, and coumarins, as opposed to legumes, may work well in protecting against a physical frailty profile of aging in a Mediterranean setting. Longitudinal investigations are needed to better understand the causal potential of diet as a modifiable contributor to frailty during aging.

Intake of omega-3 polyunsaturated fatty acids and fish associated with prevalence of low lean mass and muscle mass among older women: Analysis of Korea National Health and Nutrition Examination Survey, 2008-2011

The effects of dietary n-3 PUFA and fish on the risk of sarcopenia and muscle mass remain unclear. The present study investigated the hypothesis that intake of n-3 PUFA and fish is negatively associated with the prevalence of low lean mass (LLM) and positively correlated with muscle mass in older adults. Data from the Korea National Health and Nutrition Examination Survey, 2008-2011, 1,620 men and 2,192 women aged over 65 years were analyzed. LLM was defined as appendicular skeletal muscle mass divided by body mass index < 0.789 kg for men and <0.512 kg for women. Women and men with LLM consumed less eicosapentaenoic acid (EPA) docosahexaenoic acid (DHA) and fish. In women, but not men, the prevalence of LLM was associated with the intake of EPA and DHA (odds ratio, 0.65; 95% confidence interval, 0.48-0.90; p = 0.002) and fish (odds ratio, 0.59; 95% confidence interval, 0.42-0.82; p < 0.001). Muscle mass was also positively associated with the intake of EPA, DHA (p = 0.026), and fish (p = 0.005) in women, but not men. α-Linolenic acid intake was not associated with the prevalence of LLM and was not correlated with muscle mass. The findings suggest that consumption of EPA, DHA, and fish are negatively associated with the prevalence of LLM, and positively correlated with muscle mass in Korean older women, but not in older men.

Study on the Association Between Dietary Habits, Patterns and Frailty of the Elderly: A Cross-Sectional Survey from Communities in China

Objective

The purpose of this study was to explore the effects of Chinese dietary habits and patterns on frailty among elderly people in Xi’an the community. We also sought to provide dietary suggestions for prevention of frailty.

Methods

A cross-sectional survey was conducted and participants were divided into three groups: non-frail group, pre-frail group, and frail group. Our sample included 100 individuals randomly selected from each group for the dietary survey. Information regarding general socio-demographic characteristics and the types and quantity of food intake in the past 3 days was collected by a questionnaire. Factor analysis was used to identify dietary patterns; multiple logistic regression analysis was used to explore the correlation between dietary pattern and frailty.

Results

(1) 1693 elderly individuals were screened. The prevalence of pre-frailty and frailty was 41.0% and 16.2%, respectively. (2) Two dietary patterns were defined: ordinary dietary pattern and high-fat dietary pattern. Compared with the high-fat diet, the intake of iron, vitamin E, polyunsaturated fatty acids, and legume protein was significantly lower in the ordinary diet (P < 0.05). (3) Multivariate regression analysis showed that the ordinary dietary pattern score was positively correlated with frailty, which was consistent after adjusting for confounding factors (P < 0.05).

Conclusion

The low-fat and low-protein diet was positively correlated with the risk of frailty. Appropriate increase in fat and protein intake can help improve the frailty of the elderly in China.

Metabolites Associated with Memory and Gait: A Systematic Review

We recently found that dual decline in memory and gait speed was consistently associated with an increased risk of dementia compared to decline in memory or gait only or no decline across six aging cohorts. The mechanisms underlying this relationship are unknown. We hypothesize that individuals who experience dual decline may have specific pathophysiological pathways to dementia which can be indicated by specific metabolomic signatures. Here, we summarize blood-based metabolites that are associated with memory and gait from existing literature and discuss their relevant pathways. A total of 39 eligible studies were included in this systematic review. Metabolites that were associated with memory and gait belonged to five shared classes: sphingolipids, fatty acids, phosphatidylcholines, amino acids, and biogenic amines. The sphingolipid metabolism pathway was found to be enriched in both memory and gait impairments. Existing data may suggest that metabolites from sphingolipids and the sphingolipid metabolism pathway are important for both memory and gait impairments. Future studies using empirical data across multiple cohorts are warranted to identify metabolomic signatures of dual decline in memory and gait and to further understand its relationship with future dementia risk.

Dietary omega-3 polyunsaturated fatty acid and alpha-linolenic acid are associated with physical capacity measure but not muscle mass in older women 65-72 years

Purpose

The aim was to investigate the cross-sectional association of dietary omega-3 polyunsaturated fatty acids PUFA (alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA)) intake with multiple physical functions, muscle mass and fat mass in older women.

Method

Study subjects were 554 women from the Osteoporosis Risk Factor and Prevention Fracture Prevention Study, with dietary intake assessed with 3-day food record. Body composition was measured by dual-energy X-ray absorptiometry. Physical function measures included walking speed 10 m, chair rises, one leg stance, knee extension, handgrip strength and squat. Short physical performance battery (SPPB) score was defined based on the European working group on sarcopenia criteria.

Results

The multivariable adjusted models showed statistically significant associations for dietary ALA with higher SPPB (β = 0.118, P = 0.024), knee extension force at baseline (β = 0.075, P = 0.037) and lower fat mass (β = − 0.081, P = 0.034), as well as longer one-leg stance (β = 0.119, P = 0.010), higher walking speed (β = 0.113, P = 0.047), and ability to squat to the ground (β = 0.110, P = 0.027) at baseline. Total dietary omega-3 PUFA was associated with better SPPB (β = 0.108, P = 0.039), one-leg stance (β = 0.102, P = 0.041) and ability to squat (β = 0.110, P = 0.028), and with walking speed (β = 0.110, P = 0.028). However, associations for dietary EPA and DHA with physical function and body composition were not significant.

Conclusion

Dietary omega-3 and ALA, but not EPA and DHA, were positively associated with muscle strength and function in older women. The intake of omega-3 and its subtypes was not associated with muscle mass. Longitudinal studies are needed to show whether omega-3 intake may be important for muscle function in older women.

Simple carbohydrate intake and higher risk for physical frailty over 15 years in community-dwelling older adults

Insulin resistance is a major mechanism involved in the onset of physical frailty (PF). Although rich carbohydrate diets may promote insulin resistance, few studies have examined their association with PF risk. This study aimed to investigate the spectrum of carbohydrate exposure, including carbohydrate intake (simple, complex, and total), glycemic load (measure of the diet-related insulin-demand), and adherence to a low-carbohydrate diet with the incident risk of PF in community-dwelling older adults. Baseline carbohydrate exposure was assessed in non-frail participants of the Three-City-Bordeaux cohort using a 24H dietary recall. Over 15 years of follow-up, participants were screened for PF, defined by the FRAIL scale (≥3 criteria out of Fatigue, Resistance, Ambulation, Illnesses, and weight Loss). Associations were estimated using mixed-effects logistic models adjusted for sex, age, education, smoking status, alcohol consumption, depressive symptomatology, global cognitive performances, and protein and energy intakes. The sample included 1,210 participants (62% females, mean age 76 years). Over the follow-up, 295 (24%) incident cases of PF were documented (28% in females, 18% in males). Higher intake of simple carbohydrates was significantly associated with greater odds of incident PF (per 1-SD increased: OR = 1.29; 95% CI = 1.02-1.62), specifically among males (OR = 1.52; 95% CI = 1.04-2.22). No association was observed with complex or total carbohydrate intake, glycemic load, or low-carbohydrate diet. Among the whole carbohydrate exposure, only higher consumption of simple carbohydrates in older age was associated with a higher risk of developing PF. Further studies are required to explore underlying mechanisms.

Potentially modifiable risk factors for slow gait in community-dwelling older adults: A systematic review

PURPOSE

Slow gait speed in older adults is associated with increased risk for falls and fractures, functional dependence, multimorbidity, and even mortality. The risk of these adverse outcomes can be reduced by intervening on potentially modifiable risk factors. The purpose of this systematic review was to identify potentially modifiable risk factors associated with slow gait speed and clinically meaningful gait speed decline in older community-dwelling adults.

METHODS

Literature searches were conducted in MEDLINE, EMBASE, and CINAHL, Google Scholar, and in the bibliographies of retrieved articles.

RESULTS

Forty studies met the inclusion criteria for qualitative review. Study designs were cross-sectional and longitudinal. Operational definitions of 'slow gait' and 'meaningful gait speed decline' were variable and based on sample distributions (e.g. quartiles), external criteria (e.g. < 0.8 m/s), and dynamic changes over time (e.g. ≥ 0.05 m/s decline per year). Twenty-six potentially modifiable risk factors were assessed in at least two studies. The risk factors most commonly investigated and that showed significant associations with slow gait and/or meaningful gait speed decline include physical activity, education, body mass index-obesity, pain, and depression/depressive symptoms.

CONCLUSION

Our results suggest that there are modifiable targets to maintain gait speed that are amenable to potential treatment.

Association Between Erythrocyte Levels of n-3 Polyunsaturated Fatty Acids and Risk of Frailty in Community-Dwelling Older Adults: The Korean Frailty and Aging Cohort Study

BACKGROUND

Inflammation is a major risk factor for frailty, but n-3 polyunsaturated fatty acids (PUFA) has been suggested as an anti-inflammatory agent. The present study aimed to investigate the hypothesis that the higher erythrocyte levels of long-chain n-3 PUFA were associated with lower odds of frailty and frailty criterion.

METHODS

Cross-sectional analysis from the Korean Frailty and Aging Cohort Study, a total of 1,435 people aged 70-84 years were included. Sex- and age-stratified community residents, drawn in urban and rural regions nationwide, were eligible for participation in the study. All participants were categorized as frail and nonfrail according to the Cardiovascular Health Study index.

RESULTS

The likelihood of frailty was inversely associated with the erythrocyte levels of eicosapentaenoic acid (EPA; odds ratio [OR] per unit 0.33; 95% confidence interval [CI] 0.14-0.77; p for trend = .002) and docosahexaenoic acid (DHA; OR per unit 0.42; 95% CI 0.20-0.87; p for trend = .018). Among each frailty criterion, the likelihood of slow walking speed was associated with erythrocyte levels of EPA and DHA, and the likelihood of exhaustion was inversely associated with the erythrocyte levels of DHA.

CONCLUSIONS

The present study showed that the frailty and frailty criterion were significantly associated with lower erythrocyte levels of long-chain n-3 PUFA, suggesting that lower n-3 PUFA could be a marker for the risk of frailty.

Frailty syndrome: A target for functional nutrients?

Frailty is a late life phenotype characterized by a decline in physiological reserve across several organ systems, resulting in the increased susceptibility to endogenous and/or exogenous stressors. Although the etiology of frailty remains poorly understood, an interconnected network of putative mechanisms linked to the ageing process has been proposed. However, frailty is a dynamic process that may be prevented, delayed, or even reversed. The syndromic nature of frailty requires a multidomain approach, such as proper nutrition, as part of modifiable environmental factors, and represents one of the most promising and least costly ways to prevent and reduce frailty among older adults. Nutrient deficiencies have been consistently associated with frailty; however, mounting evidence also supports the hypothesis that beyond the traditional nutritional value, specific dietary components may exert function-enhancing effects and mitigate the extent of frailty. Thus, further mechanistic studies, along with large clinical trials, are imperative to establish the exact role of functional nutrients in the clinical management of frailty. Here, we provide a contemporary discussion of how emerging functional nutrients may contribute to modify the trajectory of the frailty syndrome.

Omega-3 Long-Chain Polyunsaturated Fatty Acids: Are They Beneficial for Physical and Cognitive Functioning in Older Adults?

BACKGROUND

There is equivocal evidence about beneficial properties of omega-3 long-chain polyunsaturated fatty acids (ω-3 LCPUFA) for older adults.

OBJECTIVE

This study investigated the relationship between circulating ω-3 LCPUFA, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels and their corresponding dietary intakes with cognition and physical function in a cohort of community-dwelling older adults at risk of dementia.

METHODS

A cross-sectional analysis was conducted among 142 community-dwelling older adults (60-85 years) with subjective memory complaints. Erythrocyte fatty acids (ω-3 LCPUFA) and the omega-3 index were measured; dietary DHA and EPA were assessed with a LCPUFA specific questionnaire. Cognition was measured using the Cogstate computerised battery and Trail-making tests. Muscle strength was assessed by grip strength and physical function via the four-square step test, 30-second sit-to-stand, timed up-and-go test, and 4-m walk test. Multiple regression analysis was used to assess the relationship between erythrocyte ω-3 LCPUFA, dietary intake, cognitive and physical function.

RESULTS

Higher dietary DHA and EPA were associated with better global cognitive function (DHA: β=0.164, p=0.042; EPA: β=0.188, p=0.020). Higher dietary EPA was associated with better attention/psychomotor composite scores (β=0.196, p=0.024), mobility (four-square step test: β=-0.202, p=0.015) and gait speed (4m walk test: β=-0.200, p=0.017). No associations were found between erythrocyte ω-3 LCPUFA and cognitive or functional performance measures.

CONCLUSIONS

In community-dwelling older adults with subjective memory complaints, higher dietary ω-3 LCPUFA intake was associated with better cognitive and physical function, supporting the evidence that ω-3 fatty acids play a role in optimising physical and cognitive health during ageing.

Effects of Omega-3 Fatty Acids on Muscle Mass, Muscle Strength and Muscle Performance among the Elderly: A Meta-Analysis

There is increasing evidence showing the role of fatty acids and their derived lipid intermediates in the regulation of skeletal muscle mass synthesis and function. However, the role of omega-3 fatty acids remains unclear. Therefore, we conducted a meta-analysis to evaluate the potential effects of omega-3 fatty acids on sarcopenia-related performances among the elderly. Eligible literature and reports of randomized controlled trials were comprehensively searched from the PubMed, Cochrane Library, ClinicalTrials.gov, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases until July 2018. A total of 10 articles were available for the meta-analysis. There were minor benefits for muscle mass gain (0.33 kg; 95% CI: 0.05, 0.62) and timed up and go performance (−0.30 s; 95% CI: −0.43, −0.17). Subgroup analyses regarding muscle mass and walk speed indicated that omega-3 fatty acid supplements at more than 2 g/day may contribute to muscle mass gain (0.67 kg; 95% CI: 0.16, 1.18) and improve walking speed, especially for those receiving more than 6 months of intervention (1.78 m/sec; 95% CI: 1.38, 2.17). Our findings provide some insight into the effects of omega-3 fatty acids on muscle mass, especially for those taking supplements at more than 2 g/day. We also observed that a long period of omega-3 fatty acids supplementation may improve walking speed.

Association of Fish Oil and Physical Activity on Mobility Disability in Older Adults

PURPOSE

This study aimed to examine whether long-term fish oil (FO) supplementation is associated with a lower risk of mobility disability and enhances benefits of physical activity (PA).

METHODS

A total of 1635 sedentary adults age 70 to 89 yr from the Lifestyle Interventions and Independence for Elders single-blinded randomized, multicenter clinical trial, which compared a structured PA program to a health education program. Primary outcome was incident major mobility disability (MMD), defined by loss of ability to walk 400 m, measured every 6 months for an average of 2.6 yr. Secondary outcomes included persistent mobility disability, Short Physical Performance Battery, 400-m walk speed, and grip strength.

RESULTS

A third of participants reported using FO at baseline (456 (28%); mean age, 78.5 yr; 70.5% women). MMD was experienced by 131 participants (28.7%) in the FO group and 405 (34.4%) participants in the nonuser group. After adjusting for confounders, FO supplementation was associated with a lower risk (HR, 0.78; 95% confidence interval (CI), 0.64-0.96) of incident MMD. However, there was no interaction (P = 0.19) between FO supplementation and PA intervention for MMD. For the secondary outcome of persistent mobility disability, the intervention association differed by supplementation (P = 0.002) with PA intervention associations of (HR, 1.36; 95% CI, 0.83-2.23) for users and (HR, 0.61; 95% CI, 0.46-0.81) for nonusers. Changes in physical performance outcomes were not modified by baseline FO supplementation or combination with PA.

CONCLUSIONS

FO supplementation was associated with a lower risk of MMD in low to moderate functioning older adults. However, supplementation did not enhance the benefit of PA on risk of mobility disability. These results are hypothesis generating and need to be confirmed in randomized trials.

Nutrition and frailty: Current knowledge

PURPOSE OF THE REVIEW

Nutrition, as part of lifestyle and modifiable environmental factors, constitutes an interesting approach for the prevention of geriatric syndromes. The objective of this review was to examine the most recent evidence on the association between nutrition, from dietary patterns to specific nutrients, and frailty, before the onset of disability, among elderly individuals.

RECENT FINDINGS

Based on available epidemiological studies, three meta-analyses published in 2018 have outlined a protective effect of greater adherence to a Mediterranean-type diet (MeDi) on the risk for frailty, with up to a 60% reduction in risk. Several studies focusing on particular food groups, macronutrients and micronutrients have also been published and have highlighted that a protein intake of 1 g/kg in body weight per day should be fulfilled (except for patients suffering from kidney or hepatic dysfunction) and that vitamin deficiencies should be avoided. Available interventional studies of nutritional supplements and/or physical activity programs have mainly been limited to disabled participants to date.

SUMMARY

Research efforts should target both developing a better understanding of the mechanisms underlying frailty and improving detection tools and the effectiveness of intervention studies, alongside efforts to address the specific needs of older people. For instance, ensuring an adequate nutritional status, by fighting the age-related increased prevalence of undernutrition or sarcopenic obesity, should be privileged.

Effect of Long-Term Omega 3 Polyunsaturated Fatty Acid Supplementation with or without Multidomain Lifestyle Intervention on Muscle Strength in Older Adults: Secondary Analysis of the Multidomain Alzheimer Preventive Trial (MAPT)

Background: The benefits of long-term omega 3 polyunsaturated fatty acid (ω3-PUFA) supplementation on muscle strength in older adults remains to be investigated. Objectives: We assessed the effect of ω3-PUFA supplementation and a multidomain (physical activity, cognitive training, and nutritional advice), alone or in combination, compared with placebo, on muscle strength. We also hypothesized that ω3-PUFA supplementation resulted in additional benefit in participants with a low docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) erythrocyte level at baseline and high adherence to the multidomain intervention sessions. Design: We performed secondary analyses of the Multidomain Alzheimer Preventive Trial (MAPT), a 3-year, multicenter, randomized, placebo-controlled trial with four parallel groups. Participants were non-demented, aged 70 years or older. They were recruited in 13 memory clinics in France and Monaco between 30 May 2008 and 24 February 2011. Participants were randomly assigned to either ω3-PUFA alone (two capsules a day providing a total daily dose of 800 mg DHA and 225 mg EPA), ω3-PUFA plus the multidomain intervention (43 group sessions integrating advice for physical activity (PA), and nutrition, cognitive training, and three preventive consultations), the multidomain intervention plus placebo, or placebo alone. Our primary outcome was the change from baseline to 36 months of the muscle strength assessed with the repeated chair stand test and handgrip strength. Results: A total of 1680 participants (75.34 years ± 4.42) were randomized. In the modified intention-to-treat population (n = 1679), no significant differences at 3-year follow-up were observed in the repeated chair stand test score between any of the three intervention groups and the placebo group. The between-group differences compared with placebo were −0.05388 (−0.6800 to 0.5723; Standard Error, SE = 0.3192; p = 0.8660) for the ω3-PUFA group, −0.3936 (−1.0217 to 0.2345; SE = 0.3180; p = 0.2192) for the multidomain intervention plus placebo group, and −0.6017 (−1.2255 to 0.02222; SE = 0.2092; p = 0.3202) for the combined intervention group. No significant effect was also found for the handgrip strength. Sensitivity analyses performed among participants with low (DHA+EPA) erythrocyte level at baseline (first quartile vs. others) or highly adherent participants (≥75% of the multidomain intervention sessions) revealed similar results. Conclusion: Low dose ω3-PUFA supplementation, either alone or in combination with a multidomain lifestyle intervention comprising physical activity counselling, had no significant effects on muscle strength over 3 years in elderly people.

The role of omega-3 in the prevention and treatment of sarcopenia

Sarcopenia is a geriatric syndrome with increasing importance due to the aging of the population. It is known to impose a major burden in terms of morbidity, mortality and socio-economic costs. Therefore, adequate preventive and treatment strategies are required. Progressive resistance training and protein supplementation are currently recommended for the prevention and treatment of sarcopenia. Omega-3 polyunsaturated fatty acids (PUFAs) might be an alternative therapeutic agent for sarcopenia due to their anti-inflammatory properties, which target the ‘inflammaging’, the age-related chronic low-grade inflammation which is assumed to contribute to the development of sarcopenia. In addition, omega-3 PUFAs may also have an anabolic effect on muscle through activation of the mTOR signaling and reduction of insulin resistance. This narrative review provides an overview of the current knowledge about omega-3 PUFAs and their role in the prevention and treatment of sarcopenia. We conclude that there is growing evidence for a beneficial effect of omega-3 PUFAs supplementation in sarcopenic older persons, which may add to the effect of exercise and/or protein supplementation. However, the exact dosage, frequency and use (alone or combined) in the treatment and prevention of sarcopenia still need further exploration.

Low Levels of Branched Chain Amino Acids, Eicosapentaenoic Acid and Micronutrients Are Associated with Low Muscle Mass, Strength and Function in Community-Dwelling Older Adults

BACKGROUND

Sarcopenia, the age-related decrease in muscle mass and function can result in adverse health outcomes and subsequent loss of independence. Inadequate nutrition is an important contributor to the aetiology of sarcopenia, and dietary strategies are studied to prevent or delay this geriatric syndrome.

OBJECTIVE

The present study investigated whether there is an association between biochemical nutrient status markers, muscle parameters and sarcopenia in community-dwelling older adults.

DESIGN

Data from the cross-sectional Maastricht Sarcopenia study (MaSS) were used, in which skeletal muscle index (SMI), 4 meter gait speed, 5 times chair stand and handgrip strength were assessed among older adults (n=227). Sarcopenia was defined following the algorithm of the European Working Group on Sarcopenia in Older People. Fasted blood samples were analyses on amino acids levels, RBC phospholipid profile, 25-hydroxyvitamin D (25(OH)D), α-tocopherol, magnesium and homocysteine were determined in fasted blood levels. Generalized linear modelling and logistic regression were used for data analysis.

RESULTS

Lower blood levels of essential amino acids (EAA), total branched-chain amino acids (BCAA) and leucine were associated with lower SMI (P<0.001), strength (P<0.001) and longer time to complete the chair stand (P<0.05), whereas no association was found for total amino acids (TAA). Lower levels of eicosapentaenoic acid (EPA), 25(OH)D and homocysteine were associated with lower muscle parameter values (P<0.05). No significant associations were found for SFA, MUFA, PUFA, n-3 and n-6 fatty acids, docosahexaenoic acid (DHA), α-tocopherol-cholesterol ratio and magnesium. Sarcopenia was more frequent among those with lower levels of leucine, BCAA, EAA, EPA, 25(OH)D and higher levels of homocysteine (P<0.05). Age and BMI were identified as relevant covariates. A robust association was only found for lower gait speed and lower 25(OH)D levels.

CONCLUSION

Compromised muscle parameters are associated with low blood values of specific amino acids, fatty acids, vitamin D and high homocysteine.

Dietary supplement intake among the elderly: hazards and benefits

PURPOSE OF REVIEW

A large percentage of older adults do not receive recommended amounts of many nutrients from food alone. Accordingly, the routine use of dietary supplements has become common among older persons. Although supplement use provides potential benefits by increasing nutrient intakes, there are potential drawbacks.

RECENT FINDINGS

Clinical studies have pointed to potential reductions in the risk to develop age-related diseases among older people who reported long-term use of multivitamin supplements. Higher plasma levels of omega-3 polyunsaturated fatty acids were also associated with fewer cardiovascular deaths in older people consuming omega-3 supplements. Dietary protein supplementation combined with exercise had a strong effect in preventing age-related muscle mass attenuation and leg strength loss in older people. Finally, beneficial effects of purified flavonoids on cognitive functions have been reported in some studies, whereas in a significant number of other studies, no such effect could be observed.

SUMMARY

The use of dietary supplements among older people has increased over the years due to the expectation of reducing the risk of developing chronic diseases. Although some dietary supplements may indeed fulfill some of these expectations, it would be unwise to assume that they are all efficacious and safe to use.

An Update on Protein, Leucine, Omega-3 Fatty Acids, and Vitamin D in the Prevention and Treatment of Sarcopenia and Functional Decline

Aging is associated with sarcopenia and functional decline, leading to frailty and disability. As a modifiable risk factor, nutrition may represent a target for preventing or postponing the onset of these geriatric conditions. Among nutrients, high-quality protein, leucine, vitamin D, and omega-3 polyunsaturated fatty acids (n-3 PUFA) are of particular interest for their demonstrated effects on skeletal muscle health. This narrative review aims to examine the recent observational and interventional evidence on the associations and the role of these nutrients in the muscle mass, strength, mobility, and physical function of free-living older adults, who are either healthy or at risk of frailty. Recent evidence supports a higher protein intake recommendation of 1.0⁻1.2 g/kg/day in healthy older adults; an evenly distributed mealtime protein intake or minimal protein per meal may be beneficial. In addition, vitamin D supplementation of 800⁻1000 IU, particularly when vitamin D status is low, and doses of ~3 g/day of n-3 PUFA may be favorable for physical function, muscle mass, and strength. Reviewed studies are highly heterogenous, yet the quantity, quality, and timing of intakes should be considered when designing intervention studies. Combined protein, leucine, vitamin D, and n-3 PUFA supplements may convey added benefits and may represent an intervention strategy in the prevention of sarcopenia and functional decline.

Omega-3 fatty acid levels in red blood cell membranes and physical decline over 3 years: longitudinal data from the MAPT study

Studies have shown that omega-3 polyunsaturated fatty acids (PUFAs) are associated with brain, cardiovascular, and immune function, as well as physical performance and bone health in older adults. So far, few studies have investigated the associations between PUFA status and performance-based tests of physical function. The objective of this study was to investigate the associations between the omega-3 PUFA levels (eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA)) in red blood cell (RBC) membranes and physical performance, in a sample of community-dwelling older adults. This is a longitudinal observational study using data from the Multidomain Alzheimer's Disease Trial (MAPT), a randomized, placebo-controlled trial. Four hundred participants from MAPT placebo group with available PUFA data were included. Omega-3 PUFA levels in RBC membranes were measured at baseline, and their percentage of total RBC membrane fatty acid content was calculated. We dichotomized the standardized omega-3 PUFA levels in RBC membranes as low (lowest quartile) vs. high (three upper quartiles). Gait speed (in m/s) and short physical performance battery (SPPB) score (range from 0 to 12, higher is better) were used to assess physical performance at baseline and after 6, 12, 24, and 36 months. Participants were 75.2 (± 4.3) years old and 68% were female. Bivariate analyses found that the characteristic of the participants in the lowest quartile of omega-3 PUFA levels (Q1) and those in the three upper quartiles (Q2-Q4) was not different at baseline; only those in Q1 were slightly older. In an unadjusted model, the difference in gait speed after 3 years of follow-up was significant (- 0.09 ± 0.03 m/s; p = 0.008) between participants in Q1 and those in Q2-Q4. In a model adjusted for age, gender, educational level, cognitive function, depressive status, body mass index, physical activity, grip strength, and their time interaction, this difference remained clinically relevant (- 0.07 ± 0.04 m/s; p = 0.075). No difference between the two groups was found for the SPPB score development over 3 years. Older adults with subjective memory complaints and in the lower quartile of omega-3 have a faster decline on gait speed compared to people in the three upper quartiles. Other longitudinal studies are needed to explore this association and to examine mechanisms.

Red blood cell membrane omega-3 fatty acid levels and physical performance: Cross-sectional data from the MAPT study

BACKGROUND & AIMS

Studies have shown that omega-3 polyunsaturated fatty acids (PUFAs) are associated with brain, cardiovascular and immune function, as well as physical performance and bone health in older adults. So far, few studies have highlighted the associations between PUFA status and performance-based tests of physical function. To study the associations between the omega-3 index (red blood cell (RBC) membrane content of omega-3 PUFAs, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) and physical performance measured with the Short Physical Performance Battery (SPPB) in a sample of community-dwelling older adults.

DESIGN

Cross-sectional study using the baseline data of the Multidomain Alzheimer's Disease Trial (MAPT), a randomized, placebo-controlled trial.

PARTICIPANTS AND MEASUREMENTS

1449 participants with available data on PUFAs were included. Omega-3 index and Short Physical Performance Battery (SPPB) scores were measured at enrollment and the omega-3 index expressed as the percentage of total fatty acid content was calculated. We also dichotomized the omega-3 index as low (lowest quartile) vs. high (three upper quartiles).

RESULTS

Participants were 75.2 (±4.4) years old, 64.5% were female. Bivariate analyses found that participants who were in the lowest omega-3 index quartile (Q1) had a SPPB score significantly lower than participants in the three other quartiles (Q2-Q4). However, adjusted (for age, gender, cognitive function, depressive status, Body Mass Index and grip strength) multiple linear regression showed that the omega-3 index-SPPB score association did not reach statistical significance [β = -0.166; (-0.346; 0.013); p = 0.07] in our sample.

CONCLUSION

This cross-sectional study found that participants with a low omega-3 index had worse performance-based test results of physical function than people with a high omega-3 index, but this association did not reach statistical significance once confounders were controlled for. Studies looking at the over-time associations between PUFA status and physical performance changes may shed more light on this topic.