Welcome to the ICD-10 code for sarcopenia

Sarcopenia: prevalence and its main risk factors in older women

Introduction: Sarcopenia is a major public health concern. It is defined as a progressive and gen­eralized skeletal muscle disorder that is associated with an increased likelihood of falls, fractures, physical disability, and ultimately, premature death.   Objective: The aim of the study was to assess the prevalence and determine the role of physical activity, nutrient intake, and selected risk factors for the development of sarcopenia in older women.   Methods: The study involved 302 women aged ≥65 years (mean age: 72.1± 5.9 years). Bioelectrical impedance analysis of body composition, static muscle strength measurements, Timed Up and Go test, and the assessment of current physical activity using accelerometers were performed. Diets were assessed using the 24-h recall method from two non-consecutive days. The energy and nutrient content of diets was calculated using the computer program DIETA 6.   Results: Sarcopenia was present in 28.8% of the women studied. The most important factor in the decrease in the risk of sarcopenia was protein intake ≥ 0.9 g/kg b.m. (OR=0.08;p<0.001), and physical activity ≥ 4000 steps/day. However, these results were not statistically significant (OR=0.58; p=0.08). Furthermore, the risk of developing sarcopenia increased as BMI (OR=1.36; p<0.001) or percent of body fat (OR=1.29; p<0.001) increased.

The Impact of Sarcopenia Onset Prior to Cancer Diagnosis on Cancer Survival: A National Population-Based Cohort Study Using Propensity Score Matching

PURPOSE

The relationship between the onset of sarcopenia prior to cancer diagnosis and survival outcomes in various types of cancer is not well understood. To address this gap in knowledge, we conducted a propensity score-matched population-based cohort study to compare the overall survival of cancer patients with and without sarcopenia.

PATIENTS AND METHODS

In our study, we included patients with cancer and divided them into two groups based on the presence or absence of sarcopenia. To ensure comparability between the groups, we matched patients in both groups at a ratio of 1:1.

RESULTS

After the matching process, our final cohort included 20,416 patients with cancer (10,208 in each group) who were eligible for further analysis. There were no significant differences between the sarcopenia and nonsarcopenia groups in terms of confounding factors such as age (mean 61.05 years versus 62.17 years), gender (52.56% versus 52.16% male, 47.44% versus 47.84% female), comorbidities, and cancer stages. In our multivariate Cox regression analysis, we found that the adjusted hazard ratio (aHR; 95% confidence interval [CI]) of all-cause death for the sarcopenia group compared to the nonsarcopenia group was 1.49 (1.43-1.55; p < 0.001). Additionally, the aHRs (95% CIs) of all-cause death for those aged 66-75, 76-85, and >85 years (compared to those aged ≤65 years) were 1.29 (1.23-1.36), 2.00 (1.89-2.12), and 3.26 (2.97-3.59), respectively. The aHR (95% CI) of all-cause death for those with a Charlson comorbidity index (CCI) ≥ 1 compared to those with a CCI of 0 was 1.34 (1.28-1.40). The aHR (95% CI) of all-cause death for men compared to women was 1.56 (1.50-1.62). When comparing the sarcopenia and nonsarcopenia groups, the aHRs (95% CIs) for lung, liver, colorectal, breast, prostate, oral, pancreatic, stomach, ovarian, and other cancers were significantly higher.

CONCLUSION

Our findings suggest that the onset of sarcopenia prior to cancer diagnosis may be linked to reduced survival outcomes in cancer patients.

Important Concepts in Protein Nutrition, Aging, and Skeletal Muscle: Honoring Dr Douglas Paddon-Jones (1969-2021) by Highlighting His Research Contributions

This review is a tribute to honor Dr Douglas Paddon-Jones by highlighting his career research contributions. Dr Paddon-Jones was a leader in recognizing the importance of muscle health and the interactions of physical activity and dietary protein for optimizing the health span. Aging is characterized by loss of muscle mass and strength associated with reduced rates of muscle protein synthesis (MPS) and the ability to repair and replace muscle proteins. Research from the team at the University of Texas Medical Branch in Galveston discovered that the age-related decline in MPS could be overcome by increasing the quantity or quality of dietary protein at each meal. Dr Paddon-Jones was instrumental in proposing and testing a "protein threshold" of ∼30 g protein/meal to optimize MPS in older adults. Dr Paddon-Jones demonstrated that physical inactivity greatly accelerates the loss of muscle mass and function in older adults. His work in physical activity led him to propose the "Catabolic Crisis Model" of muscle size and function losses, suggesting that age-related muscle loss is not a linear process, but the result of acute periods of disuse associated with injuries, illnesses, and bed rest. This model creates the opportunity to provide targeted interventions via protein supplementation and/or increased dietary protein through consuming high-quality animal-source foods. He illustrated that nutritional support, particularly enhanced protein quantity, quality, and meal distribution, can help preserve muscle health during periods of inactivity and promote health across the life course.

The accuracy of body mass index and calf circumference values when assessing sarcopenia in a multi-ethnic cohort of middle-aged and older adults: West China health and aging trend study results

Objective

This analysis was designed to explore the utility of body mass index (BMI) and calf circumference (CC) values in the diagnosis of sarcopenia.

Methods

A cross-sectional analysis of community-dwelling adults ≥50 years old was conducted. An InBody 770 bioimpedance analysis (BIA) device was used for measuring muscle mass, a grip-strength dynamometer was used to assess muscle strength, and a 4 m gait speed (GS) analysis was used to gauge physical function. The Asian Working Group for Sarcopenia (AWGS) 2019 criteria were used to define sarcopenia. The cut-off values for BMI and CC were based on the computed Younden's index values and AWGS 2019 criteria, respectively. The area under the ROC curves (AUC), specificity, sensitivity, and positive and negative predictive values (PPV and NPV) were calculated to establish the value of BMI and CC for the diagnosis of sarcopenia.

Results

In total, the data of 4177 participants ≥50 years of age were analyzed. These included 2668 (63.9%) females and 1509 (36.1%) males. Of these participants, 946 (22.6%) met the criteria for sarcopenia, including 408 (27%) males and 538 (20.2%) females. The sensitivity, specificity, and NPVs obtained when using BMI and CC values to predict sarcopenia were as follows: 84.03%/65.51%/0.90 and 74.76%/83.51%/0.87, respectively, in males; 87.36%/64.12%/0.94 and 78.25%/82.09%/0.93, in females. The respective AUC values for BMI and CC in males were 0.83 (0.80-0.85) and 0.85 (0.83-0.88), while in females they were 0.85 (0.83-0.87) and 0.88 (0.87-0.90).

Conclusions

These data suggest that BMI and CC can both serve as accurate predictors of sarcopenic incidence in a multi-ethnic population ≥50 years of age. The specificity values for BMI were relatively low in both males and females, however, underscoring the relative advantages of measuring CC when assessing individual sarcopenia risk.

Bmi-1 Overexpression Improves Sarcopenia Induced by 1,25(OH)2 D3 Deficiency and Downregulates GATA4-Dependent Rela Transcription

Sarcopenia increases with age, and an underlying mechanism needs to be determined to help with designing more effective treatments. This study aimed to determine whether 1,25(OH)₂ D₃ deficiency could cause cellular senescence and a senescence-associated secretory phenotype (SASP) in skeletal muscle cells to induce sarcopenia, whether GATA4 could be upregulated by 1,25(OH)₂ D₃ deficiency to promote SASP, and whether Bmi-1 reduces the expression of GATA4 and GATA4-dependent SASP induced by 1,25(OH)₂ D₃ deficiency in skeletal muscle cells. Bioinformatics analyses with RNA sequencing data in skeletal muscle from physiologically aged and young mice were conducted. Skeletal muscles from 2-month-old young and 2-year-old physiologically aged wild-type (WT) mice and 8-week-old WT, Bmi-1 mesenchymal transgene (Bmi-1^Tg ), Cyp27b1 homozygous (Cyp27b1^-/- ), and Bmi-1^Tg Cyp27b1^-/- mice were observed for grip strength, cell senescence, DNA damage, and NF-κB-mediated SASP signaling of skeletal muscle. We found that muscle-derived Bmi-1 and vitamin D receptor (VDR) decreased with physiological aging, and DNA damage and GATA4-dependent SASP activation led to sarcopenia. Furthermore, 1,25(OH)₂ D₃ deficiency promoted DNA damage-induced GATA4 accumulation in muscles. GATA4 upregulated Rela at the region from -1448 to -1412 bp at the transcriptional level to cause NF-κB-dependent SASP for aggravating cell senescence and muscular dysfunction and sarcopenia. Bmi-1 overexpression promoted the ubiquitination and degradation of GATA4 by binding RING1B, which prevented cell senescence, SASP, and dysfunctional muscle, and improved sarcopenia induced by 1,25(OH)₂ D₃ deficiency. Thus, Bmi-1 overexpression improves sarcopenia induced by 1,25(OH)₂ D₃ deficiency, downregulates GATA4-dependent Rela transcription, and sequentially inhibits GATA4-dependent SASP in muscle cells. Therefore, Bmi-1 overexpression could be used for translational gene therapy for the ubiquitination of GATA4 and prevention of sarcopenia. © 2023 American Society for Bone and Mineral Research (ASBMR).

Serum creatinine/cystatin C ratio is a predictor of all-cause mortality for older adults over 80 years

Objective

Sarcopenia is a prevalent condition in the senior population and has been related to adverse outcomes. This study aimed to investigate the performance of the serum creatinine/cystatin C ratio (Cr/CysC) in predicting all-cause mortality in elders over 80 years.

Methods

A total of 486 older patients over 80 were enrolled in this study. Calf circumference (CC) and handgrip strength (HGS) were carried out for each patient. All the participants accepted serum creatinine and cystatin C test. The primary clinical outcome was all-cause mortality during an over-4-year follow-up.

Results

During an over 4-year follow-up, 200 participants died. The non-survivors had a significantly lower baseline Cr/CysC level than the survivors (62.6 ± 13.1 vs. 71.4 ± 14.5 P < 0.001). The lowest Cr/CysC quartile group (Q1) had a significantly higher mortality rate than their counterparts (Q1 vs. Q2-4, 62.8% vs. 33.2%, P < 0.001). The Cr/CysC level was positively correlated with CC (R² = 0.17, P < 0.001) and HGS (R² = 0.19, P < 0.001). Moreover, survival curve was significantly worse in the lowest Cr/CysC quartile (Log-rank test χ² = 21.09, P < 0.001). After adjustment for potential confounders, age (HR, 1.10; 95% CI, 1.06-1.14, P < 0.001), coronary heart disease (HR, 1.49; 95% CI, 1.01-2.21, P = 0.045), and lowest Cr/CysC (HR, 1.59; 95% CI, 1.12-2.24, P = 0.009) were independent factors of all-cause mortality during the over-4-year follow-up.

Conclusion

Cr/CysC, also known as Sarcopenia Index, could be used as a predictor of all-cause mortality in older adults over 80 years.

The Effects of Protein and Supplements on Sarcopenia in Human Clinical Studies: How Older Adults Should Consume Protein and Supplements

Sarcopenia is a condition in which muscle mass, strength, and performance decrease with age. It is associated with chronic diseases such as diabetes, cardiovascular disease, and hypertension, and contributes to an increase in mortality. Because managing sarcopenia is critical for maintaining good health and quality of life for the elderly, the condition has sparked concern among many researchers. To counteract sarcopenia, intake of protein is an important factor, while a lack of either protein or vitamin D is a major cause of sarcopenia. In addition, essential amino acids, leucine, β-hydroxy β-methylbutyrate (HMB), creatine, and citrulline are used as supplements for muscle health and are suggested as alternatives for controlling sarcopenia. There are many studies on such proteins and supplements, but it is necessary to actually organize the types, amounts, and methods by which proteins and supplements should be consumed to inhibit sarcopenia. In this study, the efficacy of proteins and supplements for controlling sarcopenia according to human clinical studies is summarized to provide suggestions about how the elderly may consume proteins, amino acids, and other supplements.

A Sarcopenia Index Derived from Malnutrition Parameters in Elderly Haemodialysis Patients

(1) Background: Persons with chronic kidney disease may have sarcopenia characterized by the loss of muscle mass and loss of muscle strength. However, EWGSOP2 criteria to diagnose sarcopenia are technically challenging, especially in elderly persons on hemodialysis. Sarcopenia may be associated with malnutrition. We aimed at defining a sarcopenia index derived from malnutrition parameters for use in elderly haemodialysis patients. (2) Methods: A retrospective study of 60 patients aged 75 to 95 years treated with chronic hemodialysis was conducted. Anthropometric and analytical variables, EWGSOP2 sarcopenia criteria and other nutrition-related variables were collected. Binomial logistic regressions were used to define the combination of anthropometric and nutritional parameters that best predict moderate or severe sarcopenia according to EWGSOP2, and performance for moderate and severe sarcopenia was assessed by the area under the curve (AUC) of receiver operating characteristic (ROC) curves. (3) Results: The combination of loss of strength, loss of muscle mass and low physical performance correlated with malnutrition. We developed regression-equation-related nutrition criteria that predicted moderate sarcopenia (elderly hemodialysis sarcopenia index-moderate, EHSI-M) and severe sarcopenia (EHSI-S) diagnosed according to EWGSOP2 with an AUC of 0.80 and 0.866, respectively. (4) Conclusions: There is a close relationship between nutrition and sarcopenia. The EHSI may identify EWGSOP2-diagnosed sarcopenia from easily accessible anthropometric and nutritional parameters.

Aging, Physical Exercise, Telomeres, and Sarcopenia: A Narrative Review

Human aging is a gradual and adaptive process characterized by a decrease in the homeostatic response, leading to biochemical and molecular changes that are driven by hallmarks of aging, such as oxidative stress (OxS), chronic inflammation, and telomere shortening. One of the diseases associated with the hallmarks of aging, which has a great impact on functionality and quality of life, is sarcopenia. However, the relationship between telomere length, sarcopenia, and age-related mortality has not been extensively studied. Moderate physical exercise has been shown to have a positive effect on sarcopenia, decreasing OxS and inflammation, and inducing protective effects on telomeric DNA. This results in decreased DNA strand breaks, reduced OxS and IA, and activation of repair pathways. Higher levels of physical activity are associated with an apparent increase in telomere length. This review aims to present the current state of the art of knowledge on the effect of physical exercise on telomeric maintenance and activation of repair mechanisms in sarcopenia.

Impact of sarcopenia and myosteatosis on survival outcomes for patients with head and neck cancer undergoing curative-intent treatment

Malnutrition and sarcopenia are prevalent in patients with head and neck squamous cell carcinoma (HNSCC). Pre-treatment sarcopenia and adverse oncological outcomes in this population are well described. The impact of myosteatosis and post-treatment sarcopenia is less well known. Patients with HNSCC (n = 125) undergoing chemoradiotherapy, radiotherapy alone and/or surgery were assessed for sarcopenia and myosteatosis, using cross-sectional computed tomography (CT) imaging at the third lumbar (L3) vertebra, at baseline and 3 months post-treatment. Outcomes were overall survival (OS) at 12 months and 5 years post-treatment. One hundred and one participants had a CT scan evaluable at one or two time points, of which sixty-seven (66 %) participants were sarcopenic on at least one time point. Reduced muscle attenuation affected 93 % (n = 92) pre-treatment compared with 97 % (n = 90) post-treatment. Five-year OS favoured those without post-treatment sarcopenia (hazard ratio, HR 0·37, 95 % CI 0·16, 0·88, P = 0·06) and those without both post-treatment myosteatosis and sarcopenia (HR 0·33, 95 % CI 0·13, 0·83, P = 0·06). Overall, rates of myosteatosis were high at both pre- and post-treatment time points. Post-treatment sarcopenia was associated with worse 5-year OS, as was post-treatment sarcopenia in those who had myosteatosis. Post-treatment sarcopenia should be evaluated as an independent risk factor for decreased long-term survival post-treatment containing radiotherapy (RT) for HNSCC.

Sarcopenia Is Associated with an Increased Risk of Postoperative Complications Following Total Hip Arthroplasty for Osteoarthritis

Sarcopenia is a state of catabolic muscle wasting prevalent in geriatric patients. Likewise, osteoarthritis is an age-related musculoskeletal disease affecting patients with similar demographics. Late-stage hip osteoarthritis is often treated with total hip arthroplasty (THA). As sarcopenia influences the surgical outcomes, this study aimed to assess the impact of sarcopenia on the outcomes of THA. A 1:3 matched case-control study of sarcopenic to control patients was performed using a large national database. In total, 3992 patients were analyzed. Sarcopenic patients undergoing THA were more likely to experience dislocation (odds ratio (OR) = 2.19, 95% confidence interval (CI) 1.21-3.91) within 1 year of THA. Furthermore, sarcopenic patients had higher urinary tract infection rates (OR = 1.79, CI 1.32-2.42) and a greater risk of 90-day hospital readmission (hazard ratio (HR) = 1.39, CI 1.10-1.77). Sarcopenic patients experienced more falls (OR = 1.62, CI 1.10-2.39) and fragility fractures (OR = 1.77, CI 1.34-2.31). Similarly, sarcopenic patients had higher day of surgery costs (USD 13,534 vs. USD 10,504) and 90-day costs (USD 17,139 vs. USD 13,394) compared with the controls. Ultimately, sarcopenic patients undergoing THA experience higher rates of postoperative complications and incur greater medical costs. Given the potential risks, orthopedic surgeons may consider treating or reducing the severity of sarcopenia before surgery.

SARcopenia Assessment in Hypertension: The SARAH Study

OBJECTIVES

The aims of the study were to investigate the relationship between sarcopenia and renin-angiotensin system-related disorders and to explore the effects of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers on muscle mass/function and physical performance.

DESIGN

This multicenter, cross-sectional study was performed using ISarcoPRM algorithm for the diagnosis of sarcopenia.

RESULTS

Of the 2613 participants (mean age = 61.0 ± 9.5 yrs), 1775 (67.9%) were hypertensive. All sarcopenia-related parameters (except chair stand test in males) were worse in hypertensive group than in normotensive group (all P < 0.05). When clinical/potential confounders were adjusted, hypertension was found to be an independent predictor of sarcopenia in males (odds ratio = 2.403 [95% confidence interval = 1.514-3.813]) and females (odds ratio = 1.906 [95% confidence interval = 1.328-2.734], both P < 0.001). After adjusting for confounding factors, we found that all sarcopenia-related parameters (except grip strength and chair stand test in males) were independently/negatively related to hypertension (all P < 0.05). In females, angiotensin-converting enzyme inhibitors users had higher grip strength and chair stand test performance values but had lower anterior thigh muscle thickness and gait speed values, as compared with those using angiotensin II receptor blockers (all P < 0.05).

CONCLUSIONS

Hypertension was associated with increased risk of sarcopenia at least 2 times. Among antihypertensives, while angiotensin-converting enzyme inhibitors had higher muscle function values, angiotensin II receptor blockers had higher muscle mass and physical performance values only in females.

Consensus guidelines for sarcopenia prevention, diagnosis and management in Australia and New Zealand

BACKGROUND

Sarcopenia is an age-associated skeletal muscle condition characterized by low muscle mass, strength, and physical performance. There is no international consensus on a sarcopenia definition and no contemporaneous clinical and research guidelines specific to Australia and New Zealand. The Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR) Sarcopenia Diagnosis and Management Task Force aimed to develop consensus guidelines for sarcopenia prevention, assessment, management and research, informed by evidence, consumer opinion, and expert consensus, for use by health professionals and researchers in Australia and New Zealand.

METHODS

A four-phase modified Delphi process involving topic experts and informed by consumers, was undertaken between July 2020 and August 2021. Phase 1 involved a structured meeting of 29 Task Force members and a systematic literature search from which the Phase 2 online survey was developed (Qualtrics). Topic experts responded to 18 statements, using 11-point Likert scales with agreement threshold set a priori at >80%, and five multiple-choice questions. Statements with moderate agreement (70%-80%) were revised and re-introduced in Phase 3, and statements with low agreement (<70%) were rejected. In Phase 3, topic experts responded to six revised statements and three additional questions, incorporating results from a parallel Consumer Expert Delphi study. Phase 4 involved finalization of consensus statements.

RESULTS

Topic experts from Australia (n = 62, 92.5%) and New Zealand (n = 5, 7.5%) with a mean ± SD age of 45.7 ± 11.8 years participated in Phase 2; 38 (56.7%) were women, 38 (56.7%) were health professionals and 27 (40.3%) were researchers/academics. In Phase 2, 15 of 18 (83.3%) statements on sarcopenia prevention, screening, assessment, management and future research were accepted with strong agreement. The strongest agreement related to encouraging a healthy lifestyle (100%) and offering tailored resistance training to people with sarcopenia (92.5%). Forty-seven experts participated in Phase 3; 5/6 (83.3%) revised statements on prevention, assessment and management were accepted with strong agreement. A majority of experts (87.9%) preferred the revised European Working Group for Sarcopenia in Older Persons (EWGSOP2) definition. Seventeen statements with strong agreement (>80%) were confirmed by the Task Force in Phase 4.

CONCLUSIONS

The ANZSSFR Task Force present 17 sarcopenia management and research recommendations for use by health professionals and researchers which includes the recommendation to adopt the EWGSOP2 sarcopenia definition in Australia and New Zealand. This rigorous Delphi process that combined evidence, consumer expert opinion and topic expert consensus can inform similar initiatives in countries/regions lacking consensus on sarcopenia.

Comparison of surgical complications after curative surgery in patients with oral cavity squamous cell carcinoma and sarcopenia

BACKGROUND

The study aims to clarify the association of sarcopenia with perioperative and postoperative complications in oral cavity squamous cell carcinoma (OCSCC) patients undergoing curative surgery and to understand the reasons causing the poor oncologic outcomes for OCSCC.

METHODS

We conducted a propensity score matching study to investigate the association of perioperative and postoperative outcomes in OCSCC patients with sarcopenia and without sarcopenia. A retrospective analysis of a large national data set from the Taiwan Cancer Registry Database was conducted. At least two claims for patients with a principal diagnosis of sarcopenia within the 12-month preoperative period were defined as the criteria for sarcopenia diagnosis (ICD-10-CM code M62.84). Sarcopenia was diagnosed through the measurement of low muscle strength and low muscle mass by any one of the patient's attending orthopaedic physician, rehabilitation physician, family medicine specialist or geriatrician. A multivariate logistic regression model was used to calculate the perioperative, and postoperative major complications.

RESULTS

Our final cohort included 16 293 patients with OCSCC (10 862 and 5 431 in the sarcopenia and nonsarcopenia groups, respectively) who were eligible for further analysis. The sarcopenia group was 10.40% female and 89.60% male, and the nonsarcopenia group was 9.74% female and 90.26% male. The mean age ± standard deviation (SD) were 56.44 ± 11.14 and 56.22 ± 11.29 for sarcopenia and nonsarcopenia groups. OCSCC patients with sarcopenia undergoing curative surgery had a significantly higher blood transfusion rate and volume; longer intensive care unit (ICU) stay, and hospital stay; higher postoperative 30-day mortality (adjusted odds ratio [aOR]: 1.12, 95% confidence interval [CI] [1.07, 1.56]) and rates of pneumonia (aOR: 1.34, 95% CI [1.20, 1.50]), acute renal failure (aOR: 1.45, 95% CI [1.12, 1.87]) and septicaemia (aOR: 1.29, 95% CI [1.15, 1.45]); higher postoperative first-year mortality (aOR: 1.18, 95% CI [1.13, 1.51]) and rates of pneumonia (aOR: 1.43, 95% CI [1.30, 1.56]), acute myocardial infarction (aOR: 1.52, 95% CI [1.06, 2.18]) and septicaemia (aOR: 1.29, 95% CI [1.15, 1.45]).

CONCLUSIONS

OCSCC patients with sarcopenia might exhibit more perioperative and surgical complications than those without sarcopenia.

Limited physician knowledge of sarcopenia: A survey

BACKGROUND

Sarcopenia, a reduction in skeletal muscle mass and function, is a condition that contributes to functional decline and disability in older adults. Although research on this geriatric condition has developed rapidly in recent years, little work has been done to document whether practicing physicians are incorporating sarcopenia into their clinical practice.

METHODS

An online survey of 253 practicing U.S. physicians assessed knowledge of sarcopenia, use of the term in practice, motivation for screening patients, and diagnostic and treatment approaches. They were board certified in four practice areas: internal medicine (n = 69), family medicine (n = 69), geriatrics (n = 40), or physical medicine and rehabilitation (PM&R) (n = 75).

RESULTS

Less than 20% of internists and family medicine physicians reported being very familiar with the term sarcopenia, with substantially higher familiarity at this level reported among geriatricians (70%) and among PM&R specialists (41%). Two additional findings pointed to deficiencies in sarcopenia knowledge and practice: participants substantially overestimated the prevalence of sarcopenia in older adults (44% of participants reported an expected prevalence of >25%) compared to findings from published studies (indicating 10% of older adults experience sarcopenia); over 75% reported not typically using specific diagnostic criteria or being unsure if their approach utilized any specific criteria. When asked what terminology they use in a medical chart for a patient presenting with significant loss of muscle mass and strength, only 8% said sarcopenia.

CONCLUSIONS

Sarcopenia, a condition that can have a major impact on older adults as they age, has not been fully incorporated into the knowledge base and practices of active physicians. The survey data suggest that improving physician familiarity with sarcopenia and having universal agreement on criteria for diagnosis may increase the screening for and treatment of sarcopenia.

Effects of different intervention combined with resistance training on musculoskeletal health in older male adults with sarcopenia: A systematic review

Objectives

Nowadays, there is a significant increase in the elderly population in many countries around the world, and sarcopenia is one of the most common consequences of this with resistance training being one of the best treatments. Hence, this systematic review was conducted to determine what are the effects of different combinations of resistance training-based interventions on the musculoskeletal health of older male adults with sarcopenia.

Methods

This systematic review was performed following the PRISMA 2020 guidelines. The search was performed between February and August 2022 in three electronic databases: Pubmed (MEDLINE), Web of Science (WOS) and Scopus employing different keywords combined with Boolean operators. Only 13 articles were included out of the initial 1,019.

Results

The articles studied the effects of resistance training combined with other interventions, 6 articles combined it with protein and vitamin supplementation, 4 with protein supplements only, while 3 combined it with aerobic training, finding beneficial results mainly on strength, functionality, and body composition.

Conclusion

Resistance Training combined with Aerobic Training or nutritional supplements has better effects than Resistance Training alone in older male adults with sarcopenia.

Systematic review registration

https://www.crd.york.ac.uk/prospero/#recordDetails, identifier: CRD42022354184.

From Sarcopenia to Depressive Symptoms in Elderly: A Path Analysis

BACKGROUND

Sarcopenia is an age-related progressive, generalized skeletal muscle disorder involving the accelerated loss of muscle function and muscle mass. The aim of this study was to assess the complex relationship between sarcopenia, malnutrition, cognitive impairment, physical activity, and depression in the elderly, with the potential role of quality of life as a mediator in these associations.

METHODS

A cross-sectional study was conducted on a sample (n = 298) of elderly patients admitted to Special Hospital for Rehabilitation "Termal", Vrdnik, Serbia. Sarcopenia, the risk for malnutrition, cognitive impairment, physical activity, quality of life, and depressive symptoms were measured by standardized instruments. Additional data included sociodemographic characteristics. Simultaneous assessment of the direct and indirect relationships of all determinants was performed by path analysis.

RESULTS

A total of 40% (n = 120) of the elderly were diagnosed with sarcopenia, and 42.6% had depression symptoms. The risk of malnutrition was present in 23.5%, cognitive impairment in 5.4%, and a low level of physical activity was reported in 26.2% of elderly participants. The mean reported quality of life measured by Sarcopenia and Quality of Life Questionnaire was 60 (on the scale ranging from 0 to 100; where a higher score reflects a higher quality of life). The best-fitted model (χ2/DF = 1.885, NFI = 0.987, CFI = 0.993, GFI = 0.997, RMSEA = 0.055) highlighted the mediating effect of quality of life between sarcopenia, malnutrition, cognitive impairment, lower level of physical activities and depression. According to the model, quality of life was a direct negative predictor of depressive symptoms in the elderly, while malnutrition positively affected depression.

CONCLUSIONS

The presented path model may assist rehabilitation centers in developing strategies to screen for sarcopenia and risk of malnutrition, and promote physical activity in elderly, aiming to prevent their negative effects on mental health. For the elderly currently affected by sarcopenia, we consider regenerative medicine and stem cell therapy, which, in view of their etiology, could be a potential therapeutic strategy for sarcopenia.

Prevalence of characteristics associated with sarcopenia in elders: a cross-sectional study

Objectives:

to identify the prevalence and characteristics associated with sarcopenia in elders in Primary Health Care Units.

Methods:

cross-sectional study with 384 elders. To evaluate sarcopenia, we measured: strength and muscle mass, and physical performance. The elderly were classified as having: probable sarcopenia; sarcopenia; or severe sarcopenia. The chi-squared test and the multinomial logistic regression method were used.

Results:

the prevalence of probable sarcopenia was 25.52%; of sarcopenia, 11.98%; and of severe sarcopenia, 9.90%. Probable sarcopenia is 1.75 times more prevalent in men; osteoporosis is 2.16 times more prevalent in people with severe sarcopenia; polypharmacy is 1.57 times more likely in individuals with probable sarcopenia; and calf circumference below 31 cm is 2.24 times more likely in patients with sarcopenia and 2.19 times more likely in patients with severe sarcopenia.

Conclusions:

the highest prevalence was of probable sarcopenia, and the characteristics associated with sarcopenia were sex, osteoporosis, polypharmacy, overweight, obesity, and calf circumference.

The Role of Sarcopenia in Overactive Bladder in Adults in the United States: Retrospective Analysis of NHANES 2011-2018

PURPOSE

To investigate the association between sarcopenia and overactive bladder (OAB) in a United States adult population from 2011 to 2018, and whether sarcopenia can predict the risk of OAB.

MATERIALS AND METHODS

We analyzed data from the 2011-2018 National Health and Nutrition Examination Survey in a cross-sectional study(NHANES) of 8746 participants, of whom 1213 were diagnosed with OAB, we analyzed correlations by sex, age, race, education level, marital status, household income-to-poverty ratio, hypertension, diabetes, strenuous work activity, moderate work activity, strenuous recreational activity, moderate recreational activity, blood urea nitrogen, creatinine, and uric acid levels using restricted cubic spline plots of dose-response curves, univariate and multivariate Logistic regression. Models based on sex, age, education, household income to poverty ratio, hypertension, diabetes, sarcopenia index, and cotinine were developed and evaluated using Nomogram, calibration curves, receiver operating characteristic curves, and clinical decision curves.

RESULTS

Of the 1213 OAB patients, 388 (32.0%) were male and 825 (68.0%) were female. Univariate and multivariate Logistic regression analysis showed that sarcopenia index was negatively correlated with the prevalence of OAB (OR=0.084, 95% CI, 0.056 - 0.130, P <0.001;OR=0.456, 95%CI, 0.215-0.968, P= 0.0041). Dose curve analysis of the sarcopenia index and prevalence of OAB showed that the prevalence of OAB decreased significantly with increasing sarcopenia index. Sarcopenia was positively correlated with OAB (OR=2.400, 95%CI, 2.000 - 2.800, P <0.001;OR=1.46, 95%CI, 1.096 -1.953, P = 0.010). In addition, our model shows that sarcopenia can predict the prevalence of OAB (AUC = 0.750) and has some clinical decision-making implications.

CONCLUSION

Sarcopenia is positively associated with the risk of OAB in United States adults and can be used as a predictor of OAB prevalence.

The Association of Sarcopenia and Central Obesity with Mortality Risk in Patients with Chronic Kidney Disease - a 2-Year Observational Study

Background

Patients with chronic kidney disease (CKD) face numerous challenges regarding their nutritional status, including undernutrition, wasting, overweight, and obesity. However, there is a gap in the knowledge on the importance of nutritional status on the survival of CKD in patients along the spectrum of progression of CKD.

Objectives

This study aimed to investigate the association of several nutritional measures with all-cause mortality. The hypothesis was that indicators of nutritional status exceeding BMI are associated with increased mortality risk.

Methods

One-hundred seventy adult patients with predialysis CKD (n = 82), receiving hemodialysis (n = 42) or kidney transplantation (n = 46) were recruited from 2014 to 2019. At baseline, nutritional status was assessed by anthropometry, body composition, and muscle function by handgrip strength. Patient survival was assessed after a 2-y follow-up by Cox regression models adjusted for age, sex, and renal function and generalized additive models.

Results

Thirty-one patients (18%) died during the 2-y follow-up. Sarcopenia (n = 30) was associated with an increased risk of death (HR: 2.92; 95% CI: 1.24, 6.89), whereas central obesity (n = 82) was not associated with mortality (1.05; 0.51, 2.15) in the Cox regression analyses. An association between BMI and mortality risk per unit increase (0.97; 0.90, 1.05) was not observed. Other markers of nutritional status were inversely associated with mortality risk, including handgrip strength (0.89; 0.83, 0.95), mid-upper arm circumference (0.86; 0.78, 0.95), and phase angle (per 0.1 degree increase 0.86; 0.81, 0.92). In the generalized additive models, U-shaped relationships were observed between mortality risk and waist circumference and mid-upper arm muscle circumference, while BMI < 22 kg/m2 was associated with increased mortality risk.

Conclusions

Sarcopenia, but not central obesity was associated with total mortality in patients with CKD. The inclusion of muscle strength and mass measures in clinical practice should be considered.

Usefulness of muscle ultrasound in appendicular skeletal muscle mass estimation for sarcopenia assessment

The measurement of skeletal muscle mass is essential for the diagnosis of sarcopenia. Muscle ultrasonography has emerged as a useful tool for evaluating sarcopenia because it can be used to assess muscle quality and quantity. This study investigated whether muscle ultrasonography is effective for estimating appendicular skeletal muscle mass (ASM) and screening for sarcopenia. This study prospectively enrolled 212 healthy volunteers aged 40-80 years. ASM was measured using the bioelectrical impedance analysis. Muscle thickness (MT) and echo-intensity (EI) were measured in four muscles (biceps brachii, BB; triceps brachii, TB; rectus femoris, RF; biceps femoris, BF) on the dominant hand. A hold-out cross-validation method was used to develop and validate the ASM prediction equation. In the model development group, the ASM prediction equations were deduced as follows: estimated ASM for men (kg) = 0.167 × weight (kg) + 0.228 × height (cm) + 0.143 × MT of BF (mm)- 0.822 × EI to MT ratio of BB- 28.187 (R2 = 0.830) and estimated ASM for women (kg) = 0.115 × weight + 0.215 × height (cm) + 0.139 × MT of RF-0.638 × EI to MT ratio of BB- 23.502 (R2 = 0.859). In the cross-validation group, the estimated ASM did not significantly differ from the measured ASM in both men (p = 0.775; intraclass correlation coefficient [ICC] = 0.948) and women (p = 0.516; ICC = 0.973). In addition, multiple logistic regression analysis revealed that the ratios of EI to MT in the BF and RF muscles in men and MT in the BB muscle in women could be valuable parameters for sarcopenia screening. Therefore, our study suggests that muscle ultrasound could be an effective tool for estimating ASM and screening sarcopenia.

The impact of sarcopenia on the postoperative outcome in colorectal cancer surgery

Background and aim

Malnutrition-induced sarcopenia predicts poorer clinical outcomes for patients with cancer. Postoperative complications such as wound infection, anastomotic leak (AL), cardiorespiratory events are the most frequent and devastating postoperative complications in colorectal cancer surgery and are frequently associated with malnutrition.

Methods

We reviewed the recent available literature to assess the relationship between the patient nutritional status and sarcopenia in colorectal surgery. The PubMed database was searched for publications. The included studies were original articles, prospective and randomized trials, clinical, systematic reviews and meta-analyses. The information was structured in a narrative review form.

Results

A simple method to assess malnutrition is to define the presence of sarcopenia (skeletal muscle mass reduction and modified composition) by radiological image analysis. Quantifying the material composition and quality is a novel method in patient-specific therapy. This could be a new perspective in colorectal surgery to reduce postoperative mortality, improve surgical planning, and enhance clinical outcomes. A few recent studies have objectively investigated the presence of sarcopenia in colorectal cancer and its impact on morbidity and mortality, but sometimes the results are contradictory.

Conclusion

There is evolving research to find the most appropriate management method, surgeons must be aware of the existence of sarcopenia to identify this risk factor in the occurrence of postoperative complications in colorectal cancer surgery.

Identification and Functional Characterization of Metabolites for Skeletal Muscle Mass in Early Postmenopausal Chinese Women

Low skeletal muscle mass (SMM) is a crucial component of the sarcopenia phenotypes. In the present study, we aim to identify the specific metabolites associated with SMM variation and their functional mechanisms of decreased SMM in early postmenopausal women. We performed an untargeted metabolomics analysis in 430 early postmenopausal women to identify specific metabolite associated with skeletal muscle mass indexes (SMIes). Then, the potential causal effect of specific metabolite on SMM variation was accessed by one-sample Mendelian randomization (MR) analysis. Finally, in vitro experiments and transcriptomics bioinformatics analysis were conducted to explore the impact and potential functional mechanisms of specific metabolite on SMM variation. We detected 65 metabolites significantly associated with at least one SMI (variable importance in projection > 1.5 by partial least squares regression and p < .05 in multiple linear regression analysis). Remarkably, stearic acid (SA) was negatively associated with all SMIes, and subsequent MR analyses showed that increased serum SA level had a causal effect on decreased SMM (p < .05). Further in vitro experiments showed that SA could repress myoblast's differentiation at mRNA, protein, and phenotype levels. By combining transcriptome bioinformatics analysis, our study supports that SA may inhibit myoblast differentiation and myotube development by regulating the migration, adhesion, and fusion of myoblasts. This metabolomics study revealed specific metabolic profiles associated with decreased SMM in postmenopausal women, first highlighted the importance of SA in regulating SMM variation, and illustrated its potential mechanism on decreased SMM.

Are Skeletal Muscle Changes during Prolonged Space Flights Similar to Those Experienced by Frail and Sarcopenic Older Adults?

Microgravity exposure causes several physiological and psychosocial alterations that challenge astronauts' health during space flight. Notably, many of these changes are mostly related to physical inactivity influencing different functional systems and organ biology, in particular the musculoskeletal system, dramatically resulting in aging-like phenotypes, such as those occurring in older persons on Earth. In this sense, sarcopenia, a syndrome characterized by the loss in muscle mass and strength due to skeletal muscle unloading, is undoubtedly one of the most critical aging-like adverse effects of microgravity and a prevalent problem in the geriatric population, still awaiting effective countermeasures. Therefore, there is an urgent demand to identify clinically relevant biological markers and to underline molecular mechanisms behind these effects that are still poorly understood. From this perspective, a lesson from Geroscience may help tailor interventions to counteract the adverse effects of microgravity. For instance, decades of studies in the field have demonstrated that in the older people, the clinical picture of sarcopenia remarkably overlaps (from a clinical and biological point of view) with that of frailty, primarily when referred to the physical function domain. Based on this premise, here we provide a deeper understanding of the biological mechanisms of sarcopenia and frailty, which in aging are often considered together, and how these converge with those observed in astronauts after space flight.

Sarcopenia increases the risk of early biliary infection after percutaneous transhepatic biliary stent placement

Purpose

To assess the association between sarcopenia and the risk of early biliary infection (EBI) after percutaneous transhepatic biliary stent (PTBS) placement in patients with inoperable biliary tract cancer (BTC).

Patients and methods

In this single center, retrospective observational study, patients diagnosed with inoperable BTC undergoing PTBS placement between January 2013 and July 2021 were enrolled. Preoperative sarcopenia was defined based on skeletal muscle mass measured by computed tomography images on the level of third lumbar vertebra within one month before PTBS placement. Patients were divided into two groups in accordance with the status of sarcopenia. Univariate and further multivariate logistic analyses were performed to determine predictors for EBI. Stratified and interactive analyses were conducted to investigate the stability of results. Further receiver operating characteristic curve was performed to determine the predictive value of sarcopenia on EBI after PTBS placement.

Results

Totally, 134 patients were included in this retrospective study, with 45 (33.6%) patients characterized as sarcopenia. The incidence rate of EBI was 26.9% (36/134). Multivariate analyses demonstrated that sarcopenia [Odds ratio (OR), 2.75; 95%CI: 1.11-6.77; P=0.028], obstruction length (OR, 1.04; 95%CI: 1.00-1.08; P=0.030) and diabetes (OR, 2.46; 95%CI: 1.01-5.96; P=0.047) were significant predictors of EBI. There were no significant interactions in different subgroups (P for interaction > 0.05). Moreover, the areas under the curves (AUC) revealed that the combined index containing sarcopenia, obstruction length, and diabetes showed the better predictive value (AUC= 0.723) than either one alone.

Conclusion

Sarcopenia increased the risk of EBI in patients with inoperable BTC after PTBS placement. Preoperative assessment of sarcopenia may aid in risk stratification. Patients with sarcopenia should be given intensive monitoring.

Association of Dietary Protein Intake with Muscle Mass in Elderly Chinese: A Cross-Sectional Study

Most data regarding the association between dietary protein intake and muscle mass come from developed Western countries. This cross-sectional study investigates the association between the amount and distribution of dietary protein intake and muscle mass in elderly Chinese adults. This analysis includes 4826 participants aged 60 years and above from the dataset of the China Health and Nutrition Survey (CHNS) 2018. Protein intake data were assessed using 3-day, 24 h dietary recalls. Appendicular skeletal muscle mass (ASM) was obtained using the bioelectrical impedance analysis (BIA). Two-thirds of dietary protein intake comes from plant sources in the elderly Chinese population. The median total dietary protein intake was 60.5 g/d in low muscle mass participants for males and 52.5 g/d for females, which was lower than for their respective counterparts. Compared to the lowest quartile of protein intake, the highest total protein intake group had increased muscle mass by 0.96 kg among men and by 0.48 kg among women (p < 0.0001), and the highest vegetable protein intake group had increased muscle mass by 0.76 kg among men and by 0.35 kg among women (p < 0.0001). The amount of dietary protein intake with each meal was less than 20 g. High total protein intake and high plant-based protein intake were positively associated with higher muscle mass. A U-shape was observed between total dietary protein intake and low muscle mass risk in elderly Chinese adults. It should be encouraged to increase total daily protein intake to maintain muscle health.

The landscape of aging

Aging is characterized by a progressive deterioration of physiological integrity, leading to impaired functional ability and ultimately increased susceptibility to death. It is a major risk factor for chronic human diseases, including cardiovascular disease, diabetes, neurological degeneration, and cancer. Therefore, the growing emphasis on "healthy aging" raises a series of important questions in life and social sciences. In recent years, there has been unprecedented progress in aging research, particularly the discovery that the rate of aging is at least partly controlled by evolutionarily conserved genetic pathways and biological processes. In an attempt to bring full-fledged understanding to both the aging process and age-associated diseases, we review the descriptive, conceptual, and interventive aspects of the landscape of aging composed of a number of layers at the cellular, tissue, organ, organ system, and organismal levels.

Lower SMI is a risk factor for dysphagia in Japanese hospitalized patients with osteoporotic vertebral and hip fracture: A retrospective study

Objectives

Many patients with osteoporotic fragile fracture often suffer from dysphagia that results in malnutrition, further deterioration of physical strength, and rehabilitation difficulties. This study aims to investigate the risk factors for dysphagia in hospitalized patients with osteoporotic vertebral and/or hip fractures.

Methods

Between January 2020 and December 2021, 569 inpatients were managed for osteoporotic vertebral or hip fractures. Of these, 503 patients were analyzed and 66 were excluded as the required data could not be obtained or dysphagia with causative diseases such as cerebrovascular disease. The patients were divided into 2 groups: patients with dysphagia (P-group) and patients without dysphagia (N-group). We investigated gender, fracture site, age, systemic skeletal muscle mass index (SMI), bone mineral density (BMD), and body mass index (BMI) in early stage of hospitalization and studied their relationship with dysphagia.

Results

There were no significant differences in gender and fracture site between the 2 groups. A significant difference was observed in age, SMI, BMD, and BMI (P < 0.01). We performed a logistic regression analysis with the P-group as the objective variable and age, SMI, BMD, and BMI as explanatory variables. We divided objective groups into all patients, patients with vertebral fracture, patients with hip fracture, men, and women. SMI was an independent risk factor in all groups.

Conclusions

Lower SMI was a risk factor for dysphagia in hospitalized patients with osteoporotic vertebral and hip fractures. We carefully observed swallowing function of patients with decreased SMI to maintain the nutritional status and prevent rehabilitation difficulties.

Is age-related sarcopenia a real concern for my developing country?

Ageing is a distinctive feature of living organisms. With the modernization of human societies, including the development of science, technology and education, expected life expectancy at birth is being extended. This allows novel health-related conditions to gain particular interest amongst the field experts. Along comes sarcopenia, an age-related condition of global proportions that effects all populations, societies and countries. Several international working groups have been trying to identify the more appropriate and applicable sarcopenia definition and diagnostic criteria to follow. Contrary to the initial muscle mass-related context, the shift of attention to muscle strength by the revised European Working Group in Sarcopenia for Older People (EWGSOP2) was ground-breaking and potentially game-changing. The suggested diagnostic algorithm by the EWGSOP2 for case finding, diagnosing and quantifying the severity of cases further facilitated the applicability on clinical practices. Since being directly related to the ageing process, sarcopenia presents an issue of growing concern particularly within the high-income and developed world regions that are generally characterized with an increased life expectancy. In contrast, the developing world and their generally lower life expectancy do not always have sarcopenia amongst the top targeted health-related concerns. In such cases, the expected life expectancy and the populations' quality of life do not necessarily present an issue of major interest. Other serious medical concerns of acute state often eclipse the need for long-term health-related investments, shifting the interest towards only direct interventions and short-term planning. In conclusion, the emerging of sarcopenia as a serious age-related concern is finding care providers and healthcare systems from lower and middle-income countries (LMICs) unprepared. For the time being, it needs to be introduced and promoted in the developing world as a condition with direct life-threatening implications. Simple and creative forms of approach should be ideated and implemented in both scientific and clinical contexts (by researchers and care providers, respectively). The best practice to address this situation would be by empowering intradisciplinary and interdisciplinary collaborations, as well as facilitating interconnections between researches, healthcare practitioners and clients. This should help establish sarcopenia as a serious age-related condition that needs a multidisciplinary and multidimensional approach.

Prognostic value of creatinine-to-cystatin c ratio in patients with type 2 diabetes mellitus: a cohort study

BACKGROUND

The serum creatinine-to-cystatin C ratio (Scr/Scys) has been suggested as a surrogate marker of muscle mass and a predictor of adverse outcomes in many diseases. However, the prognostic value of Scr/Scys in patients with type 2 diabetes mellitus (T2DM) is unknown. The aim of this study is to assess the prognostic value of Scr/Scys in patients with T2DM.

METHODS

In this retrospective observational study, we enrolled 3668 T2DM patients undergoing coronary angiography (CAG). Serum creatinine (Scr) and serum cystatin C (Scys) levels were measured at admission. The study population was separated into low muscle mass (low-MM) and normal muscle mass (normal-MM) groups by Scr/Scys cut-off point. The association between muscle mass and long-term all-cause mortality was examined using Cox regression analysis.

RESULTS

During a median follow-up of 4.9 (3.0-7.1) years, a total of 352 (9.6%) patients died. The mortality was higher in patients with low-MM as compared with patients with normal-MM (11.1% vs. 7.3%; p < 0.001). Low muscle mass was associated with increased risk for long-term all-cause mortality, regardless of whether Scr/Scys were used as a continuous variable (adjusted hazard ratio: 1.08 [95% confidence interval (CI) 1.03 to 1.13]; p = 0.009) or a categorial variable (adjusted hazard ratio: 1.36 [95% CI 1.03 to 1.75]; p = 0.021).

CONCLUSION

Low muscle mass assessed by Scr/Scys was associated with increased risk of long-term all-cause mortality in diabetic patients.

Muscle mass loss is associated with physical dysfunction in patients with early rheumatoid arthritis

Background

Muscle mass loss is common in long-standing rheumatoid arthritis (RA). The aim was to explore the prevalence and effects of RA disease characteristics in patients with early RA.

Methods

This cross-sectional study was carried out based on a Chinese RA cohort and control subjects. The body composition (BC) was assessed using bioelectric impedance analysis. Myopenia was defined by an appendicular skeletal muscle mass index of ≤ 7.0 kg/m2 in men and ≤ 5.7 kg/m2 in women. Physical dysfunction was defined as a health assessment questionnaire disability index > 1. Propensity score matching was performed to balance age and gender differences among patients with early RA (disease duration ≤ 12 months) and established RA, and controls (with 1:3:3 matching).

Results

In total, 2017 controls and 1,008 patients with RA were recruited for this study. Among the patients with RA, there were 190 (18.8%) patients with early RA, with a median disease duration of 7 (4, 11) months. The matched patients with early RA (n = 160) showed a higher prevalence of myopenia than the matched controls (41.3 vs. 15.8%, P < 0.0167), but no difference was found in the matched patients with established RA (41.3 vs. 50.4%, P > 0.0167). Compared with the patients with established RA, the patients with early RA exhibited higher disease activity scores [disease activity score in 28 joints with four variables including C-reactive protein (DAS28-CRP): median 4.76 vs. 3.93, P < 0.001] and a higher prevalence of physical dysfunction (26.3 vs. 19.4%, P = 0.035). In the patients with early RA, patients with myopenia showed a higher prevalence of physical dysfunction than those without myopenia (41.3 vs. 15.5%, P < 0.001), among which walking and common daily activities were the most involved subdimensions. Multivariate logistic regression analysis showed that DAS28-CRP was positively associated with myopenia [adjusted odds ratio (AOR) 1.558, 95% CI (1.138-2.132)], and myopenia [AOR 2.983, 95% CI (1.192-7.465)] was independently associated with physical dysfunction in the patients with early RA.

Conclusion

Our data indicate the importance of early detection of muscle involvement in the early stage of RA and imply the significance of early aggressive control of disease activity for the prevention of myopenia and physical dysfunction in patients with early RA. Our study provides a new perspective on RA management.

Complementary combination of biomarkers for diagnosis of sarcopenia in C57BL/6J mice

AIMS

The objective of this study is to provide a reliable strategy for the diagnosis of sarcopenia based on a complementary combination of biomarkers from various approaches.

MATERIAL AND METHODS

A total of 30 C57BL/6J mice were used for the experiment, in which 15 young mice (YM) at 24 weeks old and 15 aged mice (AM) at 88 weeks old. Extracted features-based digital biomarkers from the electromyography activity of tibialis anterior muscles were evaluated by using receiver operating characteristic analysis. Extracted tissular proteins and circulating hormones based chemical biomarkers were investigated by using immunoblotting and enzyme-linked immunosorbent assay.

KEY FINDINGS

In terms of digital biomarkers, the feature-based classification of mice groups showed good performance (Feature A: AUC = 0.986, accuracy = 0.928) and (Feature B: AUC = 0.999, accuracy = 0.990). On the other hand, muscle-specific protein levels based chemical biomarkers (e.g. MuRF1, FoxO1, and perilipin2) were observed significantly increase with age. Pro-inflammatory cytokines based biomarkers extracted from muscle tissue and circulating plasma (e.g. TNF-α, IL-6, and IL-8) were significantly higher in case of AM group compared to YM group. Circulating hormone-based chemical biomarkers (e.g. cortisol/DHEA ratio and cathepsin D) presented a significant increase in concentrations with age. Circulating neurotransmitter based biomarkers (e.g. acetylcholine, serotonin, and histamine) also increased significantly in concentrations from YM to AM.

SIGNIFICANCE

A complementary combination of digital and chemical biomarkers covers multiple domains of sarcopenia to provide an effective strategy for the early diagnosis of sarcopenia.

Emerging Nutrition Approaches to Support the Mind and Muscle for Healthy Aging

This narrative review highlights recent advances and ongoing trials using nutrition approaches for healthy aging. Focus will be placed on nutrition therapies that target cognition ("the mind") and mobility ("the muscle"), both critical components to maintaining a high quality of life for older adults. For "the mind," two seemingly incongruent therapies are being investigated to improve cognition-the MIND diet (high in carbohydrates and anti-oxidant fruits and vegetables) and the ketogenic diet (low in carbohydrates, high in fats). For "the muscle," a focus on protein and energy intake has dominated the literature, yet a recent clinical trial supports the use of whole-grains as a tool to improve whole-body protein turnover-a primary regulator of lean body mass and muscle. Finally, emerging data and clinical trials on caloric restriction have solidified this strategy as the only nutritional approach to slow intrinsic factors of whole-body aging, which may positively impact both "the mind" and "the muscle."

Description and comparison of postoperative functioning of patients with hip fracture 2018 and 2008 at the Örebro University Hospital - a comparative cross-sectional study

Background

Hip fractures are a global problem, and it will probably increase. Hip fractures impair health aspects which creates demands on postoperative care. This study describes and compares patients with hip fracture in 2008 and in 2018. An increased knowledge of this group could be a basis how to optimize aftercare and dimension rehabilitation.

Methods

Using a comparative cross-sectional study to describe and compare patients with hip fracture from 2018 and 2008 at Örebro University Hospital regarding age, sex, multimorbidity, fracture type, surgical materials, surgery within 24 hours, length of stay, postoperative walking ability, physical activity level and hand grip strength. Data was collected from 76 patients with hip fracture from 2018 and 78 patients from 2008. Outcome measures considering functioning were walking ability (Functional Ambulation Categories), physical activity level (Classification system of physical activity) and hand grip strength (Jamar hand dynamometer). Statistical analyses used were hypothesis tests and regressions analysis.

Results

No differences in age, sex, fracture type, proportion of surgery within 24 hours or length of stay between the cohorts. The cohort 2018 had more multimorbidity in number of diagnoses and ASA-classification preoperatively. In 2018 70% of the participants were dependent in walking ability (physical human support) compared to 43% 2008 (p = 0.007). Proportion of physically inactive was 9% in 2018 compared to 21% 2008 (p = 0.047). Hand grip strength was 5.1 kg better in 2018 (p = 0.011). Adjusted for age, sex, ASA-classification (American Society of Anaesthesiologists Classification System), surgical materials and number of days between surgery and testing the cohort of 2018 had a lower odds to have independent walking ability and higher odds to be physical active. Differences in hand grip strength decreased to 4.7 kg. Participants in 2018 suffered significantly more multimorbidity.

Conclusions

Study indicated differences in patients’ postoperative functioning between 2018 and 2008 with more impaired walking ability, more multimorbidity, higher proportion of physically active and better hand grip strength 2018. The results are important for future reasoning regarding care needs of patients with hip fracture.

Global research in sarcopenia: High-cited papers, research institutions, funding agencies and collaborations, 1993-2022

BACKGROUND AND AIMS

This bibliometric analysis aims to analyze the high-cited papers (HCPs), those which have received >100 citations) on Sarcopenia to provide insight into publication performances and research characteristics of the literature.

METHODS

Global HCPs on Sarcopenia research were identified from the Scopus database from January 1993 to August 2022. VOSviewer, and Biblioshiny software were used to visualize the collaborative interaction among most productive countries, organizations, authors, and keywords. Select bibliometric measures were applied to evaluate the publication productivity and their influence in this area.

RESULTS

Out of 6219 publications on Sarcopenia only 398 were HCPs. These HCPs received an average of 271.7 citations per publication (CPP). The most productive organizations were the Università Cattolica del Sacro Cuore, Italy, and Jean Mayer USDA Human Nutrition Center on Aging, USA. The most impactful organizations in terms of CPP and relative citation index were CHU de Toulouse, France, and Università Cattolica del Sacro Cuore, Italy. The most productive authors were Landi F and Morley JE, and Anker SD from Italy and Germany respectively. The most impactful authors were: Cederholm T (Sweden), Cruz JAJ (Spain) and Rolland Y (France). There were few/no HCPs from South America, Africa, South Asia, and USSR.

CONCLUSION

Sarcopenia research has been predominantly done in USA, Europe, and China, and rarely from low and middle-income countries. Further focus of research should be on its etiopathogenesis (especially at the molecular level), prevalence in different communities, methods to diagnose it in early stages, and its cost-effective management.

Prescription of resistance training for sarcopenic older adults: Does it require specific attention?

Sarcopenia is an age-related neuromuscular disease characterized by substantial muscle atrophy, dynapenia and/or loss of physical function. Sarcopenia progression increases the risk for numerous negative events, including falls, disability, hospitalization, nursing home placement, and death. As such, this condition is recognized as an important topic in gerontology and geriatrics. The best approach to counteract the development and progression of sarcopenia is actively debated. Resistance training (RT) has received special attention in this context, owing to the large number of studies showing its ability to produce significant improvements in sarcopenia-related parameters. Recommendations to guide RT prescription for older adults with different conditions, including people who have traits of sarcopenia, have been published. Some authors have argued that RT guidelines for older adults are similar to one another, which may indicate that the presence of sarcopenia does not require specific physical exercise programs. However, older people with sarcopenia might present with peculiar physical, biomechanical, physiological, and psychosocial characteristics that, in our view, are not taken into adequate consideration in existing exercise guidelines. Here, we present evidence to support the view that RT prescription for older adults with sarcopenia is complex, multifactorial, and still needs more evidence.

Sarcopenia in urologic oncology: Identification and strategies to improve patient outcomes

Sarcopenia is the loss of muscle mass and function related to aging, undereating, disease conditions, or inactivity. Pre-existing sarcopenia diminishes the functional reserve of patients with cancer which increases their risk for frailty, cancer cachexia, and worse outcomes from treatments. The pathogenesis of sarcopenia is multi-factorial: opening opportunities for clinicians to work across disciplines to improve patient outcomes and quality of life. The purpose of this essay is to describe sarcopenia, discuss clinical screening and assessment for sarcopenia, and highlight potential interventions to manage sarcopenia in the urologic oncology population.

Portable Digital Monitoring System for Sarcopenia Screening and Diagnosis

Sarcopenia is a well-known highly prevalent muscle disease that severely impairs overall physical performance in elders, inducing a massive health-related economic burden. The widespread screening, diagnosis and treatment of sarcopenia are pivotal to restrain the disease progression and constrain its societal impact. Simple-to-use, portable, and reliable methods to evaluate sarcopenia are scarce, and sarcopenia-related assessments are typically done in several time-consuming stages. This study presents a portable digital system that enables a simple and intuitive method to evaluate sarcopenia-based on the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) algorithm-including the four Find-Assess-Confirm-Severity (FACS) steps. The system comprises a mobile application (app); two wireless devices: a dynamometer (Gripwise) and a skinfold caliper (Lipowise); and a back-end website. To find cases, the SARC-F questionnaire is applied. To assess sarcopenia, the handgrip strength and the sit-to-stand tests are performed with the Gripwise and an application-embedded stopwatch, respectively. To confirm cases, anthropometric measures are performed, and muscle quantity is estimated with Lipowise. Finally, to assess severity, the app stopwatch grants the gait speed test application, evaluating physical performance. This step-by-step sarcopenia assessment results in a final grading according to the cut-off points of the EWGSOP2 criteria. All data is automatically encrypted and exported into a GDPR-compliant cloud platform, in which healthcare professionals can access and monitor their patients through the internet.

Clinical assessment for diet prescription

Accurate nutritional assessment based on dietary intake, physical activity, genetic makeup, and metabolites is required to prevent from developing and/or to treat people suffering from malnutrition as well as other nutrition related health issues. Nutritional screening ought to be considered as an essential part of clinical assessment for every patient on admission to healthcare setups, as well as on change in clinical conditions. Therefore, a detailed nutritional assessment must be performed every time nutritional imbalances are observed or suspected. In this review we have explored different techniques used for nutritional and physical activity assessment. Dietary Intake (DI) assessment is a multidimensional and complex process. Traditionally, dietary intake is assessed through self-report techniques, but due to limitations like biases, random errors, misestimations, and nutrient databases-linked errors, questions arise about the adequacy of self-reporting dietary intake procedures. Despite the limitations in assessing dietary intake (DI) and physical activity (PA), new methods and improved technologies such as biomarkers analysis, blood tests, genetic assessments, metabolomic analysis, DEXA (Dual-energy X-ray absorptiometry), MRI (Magnetic resonance imaging), and CT (computed tomography) scanning procedures have made much progress in the improvement of these measures. Genes also plays a crucial role in dietary intake and physical activity. Similarly, metabolites are also involved in different nutritional pathways. This is why integrating knowledge about the genetic and metabolic markers along with the latest technologies for dietary intake (DI) and physical activity (PA) assessment holds the key for accurately assessing one's nutritional status and prevent malnutrition and its related complications.

Sarcopenia definition, diagnosis and treatment: consensus is growing

Sarcopenia is a skeletal muscle disorder that commonly occurs with advancing age as well as with a number of long-term conditions. Recognition in clinical practice is relatively recent but important because of the association between sarcopenia and a range of adverse effects on health including impaired mobility, increased morbidity and mortality. Originally characterised as loss of muscle mass, the definition has evolved to focus on loss of skeletal muscle function, particularly strength, through a number of international definitions such as that of the European Working Group on Sarcopenia in Older People most recently revised in 2019. Progress in the decades ahead is likely to be seen with regard to use of routine health data, prescription of resistance exercise, translation of biology and epidemiology into first in man studies for new treatments, and focus on sarcopenia in low and middle-income countries. Immediate next steps include the newly formed Global Leadership Initiative on Sarcopenia to develop international consensus on definition and diagnosis.

Population-based metagenomics analysis reveals altered gut microbiome in sarcopenia: data from the Xiangya Sarcopenia Study

BACKGROUND

Several studies have examined gut microbiota and sarcopenia using 16S ribosomal RNA amplicon sequencing; however, this technique may not be able to identify altered specific species and functional capacities of the microbes. We performed shotgun metagenomic sequencing to compare the gut microbiome composition and function between individuals with and without sarcopenia.

METHODS

Participants were from a community-based observational study conducted among the residents of rural areas in China. Appendicular skeletal muscle mass was assessed using direct segmental multi-frequency bioelectrical impedance and grip strength using a Jamar Hydraulic Hand dynamometer. Physical performance was evaluated using the Short Physical Performance Battery, 5-time chair stand test and gait speed with the 6 m walk test. Sarcopenia and its severity were diagnosed according to the Asian Working Group for Sarcopenia 2019 algorithm. The gut microbiome was profiled by shotgun metagenomic sequencing to determine the microbial composition and function. A gut microbiota-based model for classification of sarcopenia was constructed using the random forest model, and its performance was assessed using the area under receiver-operating characteristic curve (AUC).

RESULTS

The study sample included 1417 participants (women: 58.9%; mean age: 63.3 years; sarcopenia prevalence: 10.0%). β-diversity indicated by Bray-Curtis distance (genetic level: P = 0.004; taxonomic level of species: P = 0.020), but not α-diversity indicated by Shannon index (genetic level: P = 0.962; taxonomic level of species: P = 0.922), was significantly associated with prevalent sarcopenia. After adjusting for potential confounders, participants with sarcopenia had higher relative abundance of Desulfovibrio piger (P = 0.003, Q = 0.090), Clostridium symbiosum (P < 0.001, Q = 0.035), Hungatella effluvii (P = 0.003, Q = 0.090), Bacteroides fluxus (P = 0.002, Q = 0.089), Absiella innocuum (P = 0.002, Q = 0.072), Coprobacter secundus (P = 0.002, Q = 0.085) and Clostridium citroniae (P = 0.001, Q = 0.060) than those without sarcopenia. The relative abundance of six species (Desulfovibrio piger, Clostridium symbiosum, Hungatella effluvii, Bacteroides fluxus, Absiella innocuum, and Clostridium citroniae) was also positively associated with sarcopenia severity. A differential species-based model was constructed to separate participants with sarcopenia from controls. The value of the AUC was 0.852, suggesting that model has a decent discriminative performance. Desulfovibrio piger ranked the highest in this model. Functional annotation analysis revealed that the phenylalanine, tyrosine, and tryptophan biosynthesis were depleted (P = 0.006, Q = 0.071), while alpha-Linolenic acid metabolism (P = 0.008, Q = 0.094), furfural degradation (P = 0.001, Q = 0.029) and staurosporine biosynthesis (P = 0.006, Q = 0.072) were enriched in participants with sarcopenia. Desulfovibrio piger was significantly associated with staurosporine biosynthesis (P < 0.001).

CONCLUSIONS

This large population-based observational study provided empirical evidence that alterations in the gut microbiome composition and function were observed among individuals with sarcopenia.

Association between Disability and Edema Index Values in Rural Older Adult Osteosarcopenia Patients

PURPOSE

This study analyzed the relationship between degree of disability and edema index [extracellular water/total body water (ECW/TBW) ratio] values in a rural population of older adult patients with osteopenia, sarcopenia, or osteosarcopenia (OS).

MATERIALS AND METHODS

This study used data from the Namgaram-2 cohort. The degree of disability was measured using the World Health Organization Disability Assessment Schedule (WHODAS) 12, and ECW/TBW ratio was calculated using bioelectrical impedance analysis. Based on ECW/TBW ratio, the participants were stratified into normal (<0.391) and abnormal (≥0.391) groups, and the mean WHODAS 12 scores were compared between the two groups. Multiple regression analysis corrected for demographic factors, smoking history, hypertension, diabetes, and serological test results was also conducted.

RESULTS

Significant differences in mean WHODAS 12 scores were observed in the healthy group (5.8±7.4 vs. 9.2±9.7, p=0.008), the osteopenia only group (7.4±8.7 vs. 12.9±12.0, p<0.001), and the OS group (16.0±13.2 vs. 23.1±17.1, p=0.004). However, no significant difference in mean WHODAS 12 score was observed in the sarcopenia only group (14.9±13.4 vs. 20.7±14.8, p= 0.051). There were significant differences in ECW/TBW ratio values between the abnormal and normal groups in the osteopenia only group (B=4.646 and p=0.001), the sarcopenia only group (B=5.097 and p=0.016), and the OS group (B=5.653 and p=0.043).

CONCLUSION

This study found that the degree of disability is related to the edema index in older patients with osteopenia, sarcopenia, or OS. Since the edema index indicates the nutritional status of an individual, proper nutrition and fluid intake are important to reduce disability.

Development and Verification of a Combined Diagnostic Model for Sarcopenia with Random Forest and Artificial Neural Network

Background

Sarcopenia is a chronic disease characterized by an age-related decline in skeletal muscle mass and function, and diagnosis is challenging owing to the lack of a clear “gold standard” assessment method.

Objective

This study is aimed at combining random forest (RF) and artificial neural network (ANN) methods to screen key potential biomarkers and establish an early sarcopenia diagnostic model.

Methods

Three gene expression datasets were downloaded and merged by searching the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) in the merged dataset were identified by R software and subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Afterward, the STRING database was employed for interaction analysis of the differentially encoded proteins. Then, RF was used to identify key genes from the DEGs, and a sarcopenia diagnostic model was constructed by ANN. Finally, the diagnostic model was assessed using a validation dataset, while its diagnostic performance was evaluated by the area under curve (AUC) value.

Results

107 sarcopenia-related DEGs were identified, and they were mainly enriched in the FoxO and AMPK signaling pathways involved in the molecular pathogenesis of sarcopenia. Thereafter, seven key genes (MT1X, FAM171A1, ZNF415, ARHGAP36, CISD1, ETNPPL, and WISP2) were identified by the RF classifier. The proteins encoded by three of these genes (CISD1, ETNPPL, and WISP2) may be potential biomarkers for sarcopenia. Finally, a diagnostic model for sarcopenia was successfully designed by ANN, achieving an AUC of 0.999 and 0.85 in the training and testing datasets, respectively.

Conclusion

We identified several potential genetic biomarkers and successfully developed an early predictive model with high diagnostic performance for sarcopenia. Moreover, our results provide a valuable reference for the early diagnosis and screening of sarcopenia in the future.

Effects of lifelong spontaneous exercise on skeletal muscle and angiogenesis in super-aged mice

There has been an increasing awareness of sarcopenia, which is characterized by a concomitant decrease in skeletal muscle mass and quality due to aging. Resistance exercise is considered more effective than aerobic exercise in terms of therapeutic exercise. To confirm the effect of long-term aerobic exercise in preventing sarcopenia, we evaluated the skeletal muscle mass, quality, and angiogenic capacity of super-aged mice that had undergone lifelong spontaneous exercise (LSE) through various experiments. Our findings show that LSE could maintain skeletal muscle mass, quality, and fitness levels in super-aged mice. In addition, ex vivo experiments showed that the angiogenic capacity was maintained at a high level. However, these results were not consistent with the related changes in the expression of genes and/or proteins involved in protein synthesis or angiogenesis. Based on the results of previous studies, it seems certain that the expression at the molecular level does not represent the phenotypes of skeletal muscle and angiogenesis. This is because aging and long-term exercise are variables that can affect both protein synthesis and the expression patterns of angiogenesis-related genes and proteins. Therefore, in aging and exercise-related research, various physical fitness and angiogenesis variables and phenotypes should be analyzed. In conclusion, LSE appears to maintain the potential of angiogenesis and slow the aging process to maintain skeletal muscle mass and quality. Aerobic exercise may thus be effective for the prevention of sarcopenia.

The top 100 most-cited articles on exercise therapy for sarcopenia: A bibliometric analysis

Objective

Vast quantities of literature regarding the applications of exercise therapy for sarcopenia have been published. The main objective of this study is to determine the top 100 most-cited articles and analyze their bibliometric characteristics.

Design

This study reports a bibliometric analysis via a systematic search of the academic literature regarding the applications of exercise therapy for sarcopenia.

Methods

All databases in the Web of Science were searched with the following strategy: term search (TS) = (exercise^* OR training OR “physical activit^*”) AND TS = (sarcopenia) on 25 February 2022. The results were presented in descending order by their total citations. The list of the top 100 articles was finally determined by negotiation of two independent researchers.

Results

The top 100 articles were published between 1993 and 2020. More than half of the articles (n = 54) were published during the decade 2006–2015. Total citations of the top 100 articles ranged from 155 to 1,131 with a median of 211.5. The average of annual citations was constantly increasing with year (P < 0.05). The most studied exercise therapy is strength/resistance training, with about 71% articles had discussed about it. The top 100 articles were from 54 different journals, and the Journal of Applied Physiology was the journal that contributed the most articles (n = 8). A total of 75 different first corresponding authors from 15 countries made contributions to the top 100 list. Luc J.C. van Loon from the Maastricht University in the Netherlands published the most articles (n = 5) as the first corresponding author. Most articles (87%) were from North America (58%) and Europe (29%), while the United States as a country contributed over half of the articles (51%).

Conclusion

Our study determined the top 100 most-cited articles on exercise therapy for sarcopenia and analyzed their bibliometric characteristics, which may provide a recommended list for researchers in this field and pave the way for further research.

Hybrid Exercise Program for Sarcopenia in Older Adults: The Effectiveness of Explainable Artificial Intelligence-Based Clinical Assistance in Assessing Skeletal Muscle Area

Background: Sarcopenia is a geriatric syndrome characterized by decreased skeletal muscle mass and function with age. It is well-established that resistance exercise and Yi Jin Jing improve the skeletal muscle mass of older adults with sarcopenia. Accordingly, we designed an exercise program incorporating resistance exercise and Yi Jin Jing to increase skeletal muscle mass and reverse sarcopenia in older adults. Additionally, machine learning simulations were used to predict the sarcopenia status after the intervention. Method: This randomized controlled trial assessed the effects of sarcopenia in older adults. For 24 weeks, 90 older adults with sarcopenia were divided into intervention groups, including the Yi Jin Jing and resistance training group (YR, n = 30), the resistance training group (RT, n = 30), and the control group (CG, n = 30). Computed tomography (CT) scans of the abdomen were used to quantify the skeletal muscle cross-sectional area at the third lumbar vertebra (L3 SMA). Participants’ age, body mass, stature, and BMI characteristics were analyzed by one-way ANOVA and the chi-squared test for categorical data. This study explored the improvement effect of three interventions on participants’ L3 SMA, skeletal muscle density at the third lumbar vertebra (L3 SMD), skeletal muscle interstitial fat area at the third lumbar vertebra region of interest (L3 SMFA), skeletal muscle interstitial fat density at the third lumbar vertebra (L3 SMFD), relative skeletal muscle mass index (RSMI), muscle fat infiltration (MFI), and handgrip strength. Experimental data were analyzed using two-way repeated-measures ANOVA. Eleven machine learning models were trained and tested 100 times to assess the model’s performance in predicting whether sarcopenia could be reversed following the intervention. Results: There was a significant interaction in L3 SMA (p < 0.05), RSMI (p < 0.05), MFI (p < 0.05), and handgrip strength (p < 0.05). After the intervention, participants in the YR and RT groups showed significant improvements in L3 SMA, RSMI, and handgrip strength. Post hoc tests showed that the YR group (p < 0.05) yielded significantly better L3 SMA and RSMI than the RT group (p < 0.05) and CG group (p < 0.05) after the intervention. Compared with other models, the stacking model exhibits the best performance in terms of accuracy (85.7%) and F1 (75.3%). Conclusion: One hybrid exercise program with Yi Jin Jing and resistance exercise training can improve skeletal muscle area among older adults with sarcopenia. Accordingly, it is possible to predict whether sarcopenia can be reversed in older adults based on our stacking model.

Nutrition mediates the relationship between number of teeth and sarcopenia: a pathway analysis

Objectives

The relationship between the number of teeth and sarcopenia remains poorly investigated. Although nutrition plays an important role in maintaining bone and muscle health, the complex relationship between number of teeth and nutrition in the pathogenesis of sarcopenia remains to be elucidated.

Methods

A large multi-ethnic sample of 4149 participants aged over 50 years old from West China Health and Aging Trend (WCHAT) study was analyzed. We examined the associations between number of teeth with nutritional status and sarcopenia, and the mediating role of nutrition in the association between number of teeth and sarcopenia. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019. We assessed nutrition using Mini Nutrition Assessment-Short Form (MNA-SF) scale. Direct relationships between number of teeth, nutrition and sarcopenia were assessed using multiple linear regression. Mediation models and structural equation model (SEM) pathway analysis were used to test the mediating role of nutrition in the relationship between number of teeth and sarcopenia.

Results

Of 4149 participants aged 50 years old or older, the prevalence of sarcopenia was 22.5, 9.0% for moderate sarcopenia, and 13.5% for severe sarcopenia, respectively. Regression analysis indicated a total association between number of teeth (β = − 0.327, 95% CI − 0.471 to − 0.237, p < 0.001) and sarcopenia. After adjusted MNA-SF scores, the association between number of teeth and sarcopenia was still significant (β = − 0.269, 95% CI − 0.364 to − 0.175, p < 0.001), indicating a partial mediation effect of nutrition. Mediation analysis verified nutrition partially mediate the associations between number of teeth and sarcopenia (indirect effect estimate = − 0.0272, bootstrap 95% CI − 0.0324 to − 0.0222; direct effect estimate = − 0.0899, bootstrap 95% CI − 0.1049 to − 0.0738). And this mediation effect was through impacting SMI (indirect effect estimate = − 0.0283, bootstrap 95% CI − 0.0336 to − 0.0232) and grip strength (indirect effect estimate = − 0.0067, bootstrap 95% CI − 0.0094 to − 0.0043). Structural equation model (SEM) framework pathway analysis confirmed the association between number of teeth, nutrition, and sarcopenia.

Conclusions

Our findings indicated that sarcopenia was associated with number of teeth and poorer nutritional status, with nutrition partially mediating the association between number of teeth and sarcopenia. Our findings supported early nutritional assessment and intervention in oral health to mitigate the risk of sarcopenia.