Dietary Inflammatory Index and Dietary Diversity Score Associated with Sarcopenia and Its Components: Findings from a Nationwide Cross-Sectional Study

Little is known about the independent and joint effects of the energy-adjusted dietary inflammatory index (E-DII) and dietary diversity score (DDS) on sarcopenia and its components (low muscle mass, low muscle strength, and low physical performance). A total of 155,669 UK Biobank participants with ≥1 (maximum 5) 24 h dietary assessments were included in this cross-sectional analysis. We used logistic regression models to investigate the associations of E-DII and DDS with sarcopenia and its three components. We further examined the joint effects of E-DII and DDS on sarcopenia and its components using additive and multiplicative interaction analyses. We observed that lower E-DII and higher DDS were associated with lower odds of sarcopenia and its components. There were significant joint associations of E-DII and DDS with sarcopenia and low physical performance (p-interaction < 0.05) on the multiplicative interactive scale. Our study suggests that lower dietary inflammatory potential and higher dietary diversity might be important protective factors against sarcopenia and its components. More cases of sarcopenia and low physical performance might be preventable by adherence to a more anti-inflammatory diet combined with a higher dietary diversity.

Prevalence of and risk factors for sarcopenia in community-dwelling people: The Vietnam Osteoporosis Study

BACKGROUND

Sarcopenia is a geriatric disease characterized by the progressive and generalized loss of skeletal lean mass and strength with age. The prevalence of sarcopenia in the Vietnamese population is unknown. This study sought to estimate the prevalence of and risk factors for sarcopenia among community-dwelling individuals in Vietnam.

METHODS

This cross-sectional study is part of the ongoing Vietnam Osteoporosis Study project. The study involved 1308 women and 591 men aged 50 years and older as at 2015 (study entry). Whole-body dual-energy X-ray absorptiometry was used to measure the appendicular skeletal lean mass. Anthropometric and clinical data were collected using a structured questionnaire. Sarcopenia was defined according to the criteria proposed by the Asian Working Group for Sarcopenia in 2019. Logistic regression analysis was used to determine the association between potential risk factors and sarcopenia.

RESULTS

The prevalence of sarcopenia in women and men was 14% (n = 183) and 16% (n = 83), respectively. Age (odds ratio [OR] per 10 years = 1.37; 95% confidence interval [CI] 1.26-1.48) and being underweight (OR = 1.61; 95% CI 1.00-2.58) were independently associated with increased risk of sarcopenia. The combination of low physical activity, being underweight and advancing age accounted for ~27% of sarcopenic patients. However, most of the attributable fraction was due to ageing.

CONCLUSIONS

Sarcopenia is common in community-dwelling Vietnamese adults, particularly those with advancing age, who are underweight and with low physical activity.

Biomarkers associated with lower limb muscle function in individuals with sarcopenia: a systematic review

Lower limb muscle dysfunction is a key driver for impaired physical capacity and frailty status, both characteristics of sarcopenia. Sarcopenia is the key pathway between frailty and disability. Identifying biological markers for early diagnosis, treatment, and prevention may be key to early intervention and prevention of disability particularly mobility issues. To identify biological markers associated with lower limb muscle (dys)function in adults with sarcopenia, a systematic literature search was conducted in AMED, CINAHL, Cochrane Library, EMBASE, Medline, PubMed, Scopus, SPORTDiscus, and Web of Science databases from inception to 17 November 2021. Title, abstract, and full-text screening, data extraction, and methodological quality assessment were performed by two reviewers independently and verified by a third reviewer. Depending on available data, associations are reported as either Pearson's correlations, regression R² or partial R² , P value, and sample size (n). Twenty eligible studies including 3306 participants were included (females: 79%, males: 15%, unreported: 6%; mean age ranged from 53 to 92 years) with 36% in a distinct sarcopenic subgroup (females: 73%, males: 19%, unreported: 8%; mean age range 55-92 years). A total of 119 biomarkers were reported, categorized into: genetic and microRNAs (n = 64), oxidative stress (n = 10), energy metabolism (n = 18), inflammation (n = 7), enzyme (n = 4), hormone (n = 7), bone (n = 3), vitamin (n = 2), and cytokine (n = 4) markers) and seven lower limb muscle measures predominately focused on strength. Seven studies reported associations between lower limb muscle measures including (e.g. power, force, and torque) and biomarkers. In individuals with sarcopenia, muscle strength was positively associated with free testosterone (r = 0.40, P = 0.01; n = 46). In analysis with combined sarcopenic and non-sarcopenic individuals, muscle strength was positively associated with combined genetic and methylation score (partial R²  = 0.122, P = 0.03; n = 48) and negatively associated with sarcopenia-driven methylation score (partial R²  = 0.401, P < 0.01; n = 48). Biomarkers related to genetics (R²  = 0.001-0.014, partial R²  = 0.013-0.122, P > 0.05; n = 48), oxidative stress (r = 0.061, P > 0.05; n ≥ 77), hormone (r = 0.01, ρ = 0.052 p > 0.05, n ≥ 46) and combined protein, oxidative stress, muscle performance, and hormones (R²  = 22.0, P > 0.05; n ≥ 82) did not report significant associations with lower limb muscle strength. Several biomarkers demonstrated associations with lower limb muscle dysfunction. The current literature remains difficult to draw clear conclusions on the relationship between biomarkers and lower limb muscle dysfunction in adults with sarcopenia. Heterogeneity of biomarkers and lower limb muscle function precluded direct comparison. Use of international classification of sarcopenia and a set of core standardized outcome measures should be adopted to aid future investigation and recommendations to be made.

Sarcopenia and malnutrition: commonly occurring conditions in the older population

This article reviews the prevalence of loss of muscle mass and function, (sarcopenia) alongside malnutrition in the older population (>65 years). It outlines what is meant by both sarcopenia and malnutrition and looks at how these conditions can interact to cause detrimental outcomes in both underweight and overweight older adults. It also details some of the potential consequences of loss of muscle mass on the effective functioning of the human body and clinical outcomes and includes tips for nurses on how they can incorporate simple strategies into everyday care to both identify and treat patients at risk of sarcopenia and malnutrition.