Sarcopenia

ACTN3 genotype and physical function and frailty in an elderly Chinese population: the Rugao Longevity and Ageing Study

Objective

To examine the associations of the actinin alpha 3 gene (ACTN3) R577X polymorphism with physical performance and frailty in an older Chinese population.

Methods

Data from 1,463 individuals (57.8% female) aged 70-87 years from the Rugao Longevity and Ageing Study were used. The associations between R577X and timed 5-m walk, grip strength, timed Up and Go test, and frailty index (FI) based on deficits of 23 laboratory tests (FI-Lab) were examined. Analysis of variance and linear regression models were used to evaluate the genetic effects of ACTN3 R577X on physical performance and FI-Lab.

Results

The XX and RX genotypes of the ACTN3 R557X polymorphism accounted for 17.1 and 46.9%, respectively. Multivariate regression analysis revealed that in men aged 70-79 years, the ACTN3 577X allele was significantly associated with physical performance (5-m walk time, regression coefficient (β) = 0.258, P = 0.006; grip strength, β = -1.062, P = 0.012; Up and Go test time β = 0.368, P = 0.019). In women aged 70-79 years, a significant association between the ACTN3 577X allele and the FI-Lab score was observed, with a regression coefficient of β = 0.019 (P = 0.003). These findings suggest an age- and gender-specific X-additive model of R577X for 5-m walk time, grip strength, Up and Go Test time, and FI-Lab score.

Conclusion

The ACTN3 577X allele is associated with an age- and sex-specific decrease in physical performance and an increase in frailty in an older population.

Protein Intake and Distribution in Relation to Physical Functioning and Quality of Life in Community-Dwelling Elderly People: Acknowledging the Role of Physical Activity

Increasing total protein intake and a spread protein intake distribution are potential strategies to attenuate sarcopenia related loss of physical function and quality of life. The aim of this cross-sectional study was to investigate whether protein intake and protein intake distribution are associated with muscle strength, physical function and quality of life in community-dwelling elderly people with a wide range of physical activity. Dietary and physical activity data were obtained from two studies (N = 140, age 81 ± 6, 64% male), with the following outcome measures: physical functioning (Short Physical Performance Battery (SPPB), comprising balance, gait speed and chair rise tests), handgrip strength and quality of life (EQ-5D-5L). Protein intake distribution was calculated for each participant as a coefficient of variance (CV = SD of grams of protein intake per main meal divided by the average total amount of proteins (grams) of the main meals). Based on the CV, participants were divided into tertiles and classified as spread, intermediate or pulse. The average total protein intake was 1.08 ± 0.29 g/kg/day. Total protein intake was not associated with outcome measures using multivariate regression analyses. Individuals with a spread protein diet during the main meals (CV < 0.43) had higher gait speed compared to those with an intermediate diet (CV 0.43⁻0.62) (β = -0.42, p = 0.035), whereas a spread and pulse protein diet were not associated with SPPB total score, chair rise, grip strength and Quality-Adjusted Life Year (QALY). The interaction of higher physical activity and higher total protein intake was significantly associated with higher quality of life (β = 0.71, p = 0.049). While this interaction was not associated with SPPB or grip strength, the association with quality of life emphasizes the need for a higher total protein intake together with an active lifestyle in the elderly.

Association between the nutritional status and the severity of sarcopenia among community-dwelling elderly Japanese people

AIM

To investigate the association between nutritional evaluation indices (body mass index, albumin, and weight loss) and sarcopenia severity among community-dwelling elderly people in Japan.

METHODS

The subjects consisted of 758 community-dwelling elderly people ≥65 years of age, categorized into two groups by based on Operation of long life medical care system (medical care system for elderly in the latter stage of life), the cut-off value for age used was 75. The outcome measures were basic characteristics, anthropometric measures, physical function, and blood biochemistry (five assessments). The appendicular skeletal muscle mass was calculated via a bioelectrical impedance analysis. The subjects were categorized into three groups by the body mass index (BMI) [BMI 3 group]. The cut-off value for albumin used was 3.8 g/dL [A1b 2 group]. Weight loss was assessed using item 11 on the Kihon check list: "Have you experienced more than 2-3 kg weight loss over the past 6 months? Yes=1, No=0." [weight loss 2 group]. Sarcopenia was defined based on the European Working Group on Sarcopenia in Older People definition, using the Asian Working Group for Sarcopenia cut-off values. All subjects were then categorized into four groups based on their sarcopenia status: non-sarcopenic (non-), pre-sarcopenic (pre-), sarcopenic (sarco-), or severely sarcopenic (severe-) [sarco4 group].

RESULTS

The prevalence of sarcopenia and severe sarcopenia in men was 5.6% (n=18) and 1.2% (n=4), respectively, and in women was 7.8% (n=34) and 1.6% (n=7), respectively. The analysis showed that, among the people (>75 years of age) with normal BMI (18.5-25.0), 10.4%-15.6% were in the Sarco group. Further, among women over 75 years of age with BMI >25.0, 5.7% (n=2) were in the Sarco group. There was a significant association between weight loss and sarcopenia severity in older men. No significant association between albumin levels and sarcopenia severity was observed. 80.0% of weight-loss was presented in above BMI 18.5 kg/m2 and Alb 3.8 g/dL.

CONCLUSION

Sarcopenia and severe sarcopenia were prevalent among those with normal BMI, and particularly among obese women over 75 years of age. Weight-loss was presented in above BMI 18.5 kg/m2 and Alb 3.8 g/dL. Our findings indicate that the nutritional evaluation indices, including BMI, albumin, and weight loss, were insufficient in screening for malnutrition and sarcopenia among the elderly.

Prevalence of sarcopenia in systemic sclerosis: assessing body composition and functional disability in patients with systemic sclerosis

OBJECTIVE

We analyzed the prevalence of sarcopenia among systemic sclerosis (SSc) patients with respect to quality of life, disability, organ involvement, and muscle function.

METHODS

A total of 129 patients who met the ACR/EULAR 2013 classification criteria were included. Body composition was measured using bioelectric impedance analysis. Sarcopenia was defined according to the criteria of the European Working Group on Sarcopenia in Older People. Handgrip and knee extension strength and pulmonary peak flow were measured. Physical function was assessed with the Short Form-36 Health Survey and Scleroderma Health Assessment Questionnaire.

RESULTS

Sarcopenia was prevalent in 22.5% of patients. There were significant differences between patients with and without sarcopenia regarding handgrip strength (11.5 [2.0-30.0] versus 18.0 [1.0-41.0] kilogram force [kgf]; P <0.001) and knee extension strength (11.0 [3.5-32.5] versus 17.5 [3.5-88.0] kgf; P = 0.006), physical function (38.8 [9.9-85.0] versus 48.8 [0-88.0]; P = 0.032) and number of immunosuppressants (2 [0-4] versus 1 [0-5]; P = 0.009). There were no differences regarding age (57.0 [32.0-83.0] versus 60.5 [28.0-82.0] years; P = 0.350) and disease duration (8 [1-27] versus 7 [0-34] years; P = 0.350).

CONCLUSIONS

Sarcopenia is common in patients with SSc and is associated with physical impairment that affects everyday life and participation in work. Interestingly, although age is the main risk factor for sarcopenia in the general population, it did not differ between sarcopenic and non-sarcopenic SSc patients in our study. Instead, the number of immunosuppressive drugs was significantly higher among sarcopenic patients.

How do we define and measure sarcopenia? Protocol for a systematic review

BACKGROUND

The loss of muscle mass is a natural aging consequence. A reduction of muscle mass that surpasses the physiological rate is considered the key factor responsible for the development of a geriatric syndrome called sarcopenia. However, a new understanding of the importance of muscle quality over quantity is rising; as a result, different definitions for sarcopenia has been used. Due to the negative impact on elder's health and quality of life, the number of research investigating the causes, prevalence, and management of sarcopenia is increasing, although a consensus on sarcopenia definition is still missing. This systematic review will assess observational studies reporting the presence of sarcopenia aiming to verify how sarcopenia is defined, the diagnosis criteria, and the tools used for assessment. In addition, we will investigate the influence of the definition and diagnostic tools on the prevalence rate.

METHODS

Keywords related to the condition, population, and type of study will be combined to build a search strategy for each of the following databases MEDLINE, EMBASE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Web of Science, and Google Scholar. Two independent reviewers will analyze the retrieved papers for eligibility and the methodological quality of eligible studies. The definition of sarcopenia and diagnostic tools used in each study and the prevalence estimates will be extracted. Descriptive statistics will be used to report the definitions of sarcopenia, diagnostic tools, and whether these influence or not, the prevalence rates.

DISCUSSION

Sarcopenia is receiving greater attention in geriatrics research in recent years. Therefore, it is important to investigate how this condition is defined in the literature and whether these definitions can interfere with the reported estimates devoting more efforts on the topic. The results of this study can help to determine the most used definitions of sarcopenia reported in the literature, its strengths and limitations, and open a discussion about a need for a more valid, easy, and suitable one.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015020832.

Foot Problems in Older Adults Associations with Incident Falls, Frailty Syndrome, and Sensor-Derived Gait, Balance, and Physical Activity Measures

BACKGROUND

Research on foot problems and frailty is sparse and could advance using wearable sensor-based measures of gait, balance, and physical activity (PA). This study examined the effect of foot problems on the likelihood of falls, frailty syndrome, motor performance, and PA in community-dwelling older adults.

METHODS

Arizona Frailty Cohort Study participants (community-dwelling adults aged ≥65 years without baseline cognitive deficit, severe movement disorders, or recent stroke) underwent Fried frailty and foot assessment. Gait, balance (bipedal eyes open and eyes closed), and spontaneous PA over 48 hours were measured using validated wearable sensor technologies.

RESULTS

Of 117 participants, 41 (35%) were nonfrail, 56 (48%) prefrail, and 20 (17%) frail. Prevalence of foot problems (pain, peripheral neuropathy, or deformity) increased significantly as frailty category worsened (any problem: 63% in nonfrail, 80% in prefrail [odds ratio (OR) = 2.0], and 95% in frail [OR = 8.3]; P = .03 for trend) due to associations between foot problems and both weakness and exhaustion. Foot problems were associated with fear of falling but not with fall history or incident falls over 6 months. Foot pain and peripheral neuropathy were associated with lower gait speed and stride length; increased double support time; increased mediolateral sway of center of mass during walking, age adjusted; decreased eyes open sway of center of mass and ankle during quiet standing, age adjusted; and lower percentage walking, percentage standing, and total steps per day.

CONCLUSIONS

Foot problems were associated with frailty level and decreased motor performance and PA. Wearable technology is a practical way to screen for deterioration in gait, balance, and PA that may be associated with foot problems. Routine assessment and management of foot problems could promote earlier intervention to retain motor performance and manage fear of falling in older adults, which may ultimately improve healthy aging and reduce risk of frailty.

Association of estimated glomerular filtration rate with muscle function in older persons who have fallen

Background

studies suggest that estimated glomerular filtration rate (eGFR) is less reliable in older persons and that a low serum-creatinine might reflect reduced muscle mass rather than high kidney function. This study investigates the possible relationship between eGFR and multiple elements of physical performance in older fallers.

Methods

baseline data of the IMPROveFALL-study were examined in participants ≥65 years. Serum-creatinine based eGFR was classified as normal (≥90 ml/min), mildly reduced (60-89 ml/min) or moderately-severely reduced (<60 ml/min). Timed-Up-and-Go-test and Five-Times-Sit-to-Stand-test were used to assess mobility; calf circumference and handgrip strength to assess muscle status. Ancova models adjusted for age, sex, Charlson comorbidity index and body mass index were performed.

Results

a total of 578 participants were included. Participants with a normal eGFR had lower handgrip strength than those with a mildly reduced eGFR (-9.5%, P < 0.001) and those with a moderately-severely reduced eGFR (-6.3%, P = 0.033) with mean strengths of 23.4, 25.8 and 24.9 kg, respectively. Participants with a normal eGFR had a smaller calf circumference than those with a mildly reduced eGFR (35.5 versus 36.5 cm, P = 0.006). Mean time to complete the mobility tests did not differ.

Conclusions

in this study we found that older fallers with an eGFR ≥ 90 ml/min had smaller calf circumference and up to 10% lower handgrip strength than those with a reduced eGFR. This lower muscle mass is likely to lead to an overestimation of kidney function. This outcome therefore supports the search for biomarkers independent of muscle mass to estimate kidney function in older persons.

Human neuromuscular aging: Sex differences revealed at the myocellular level

Age-related muscle loss (sarcopenia) is a major clinical problem affecting both men and women - accompanied by muscle weakness, dysfunction, disability, and impaired quality of life. Current definitions of sarcopenia do not fully encompass the age-related changes in skeletal muscle. We therefore examined the influence of aging and sex on elements of skeletal muscle health using a thorough histopathological analysis of myocellular aging and assessments of neuromuscular performance. Two-hundred and twenty-one untrained males and females were separated into four age cohorts [mean age 25 y (n = 47), 37 y (n = 79), 61 y (n = 51), and 72 y (n = 44)]. Total (-12%), leg (-17%), and arm (-21%) lean mass were lower in both 61 y and 72 y than in 25 y or 37 y (P < 0.05). Knee extensor strength (-34%) and power (-43%) were lower (P < 0.05) in the older two groups, and explosive sit-to-stand power was lower by 37 y (P < 0.05). At the histological/myocellular level, type IIx atrophy was noted by 37 y and type IIa atrophy by 61 y (P < 0.05). These effects were driven by females, noted by substantial and progressive type IIa and IIx atrophy across age. Aged female muscle displayed greater within-type myofiber size heterogeneity and marked type I myofiber grouping (~5-fold greater) compared to males. These findings suggest the predominant mechanisms leading to whole muscle atrophy differ between aging males and females: myofiber atrophy in females vs. myofiber loss in males. Future studies will be important to better understand the mechanisms underlying sex differences in myocellular aging and optimize exercise prescriptions and adjunctive treatments to mitigate or reverse age-related changes.

Alterations in the in vitro and in vivo regulation of muscle regeneration in healthy ageing and the influence of sarcopenia

BACKGROUND

Sarcopenia is defined as the age-related loss of skeletal muscle mass and function. While all humans lose muscle with age, 2-5% of elderly adults develop functional consequences (disabilities). The aim of this study was to investigate muscle myogenesis in healthy elderly adults, with or without sarcopenia, compared with middle-aged controls using both in vivo and in vitro approaches to explore potential biomarker or causative molecular pathways associated with sarcopenic versus non-sarcopenic skeletal muscle phenotypes during ageing.

METHODS

Biomarkers of multiple molecular pathways associated with muscle regeneration were analysed using quantitative polymerase chain reaction in quadriceps muscle samples obtained from healthy elderly sarcopenic (HSE, n = 7) or non-sarcopenic (HENS, n = 21) and healthy middle-aged control (HMC, n = 22) groups. An in vitro system of myogenesis (using myoblasts from human donors aged 17-83 years) was used to mimic the environmental challenges of muscle regeneration over time.

RESULTS

The muscle biopsies showed evidence of satellite cell activation in HENS (Pax3, P < 0.01, Pax7, P < 0.0001) compared with HMC. Early myogenesis markers Myogenic Differentiation 1 (MyoD1) and Myogenic factor 5 (Myf5) (P < 0.0001) and the late myogenesis marker myogenin (MyoG) (P < 0.01) were increased in HENS. In addition, there was a 30-fold upregulation of TNF-α in HENS compared with HMC (P < 0.0001). The in vitro system demonstrated age-related upregulation of pro-inflammatory cytokines (2-fold upregulation of interleukin (IL)-6, IL-8 mRNA, increased secretion of tumor necrosis factor-α (TNF-α) and IL-6, all P < 0.05) associated with impaired kinetics of myotube differentiation. The HSE biopsy samples showed satellite cell activation (Pax7, P < 0.05) compared with HMC. However, no significant upregulation of the early myogenesis (MyoD and Myf5) markers was evident; only the late myogenesis marker myogenin was upregulated (P < 0.05). Higher activation of the oxidative stress pathway was found in HENS compared with the HSE group. In contrast, there was 10-fold higher upregulation of HSPA1A a stress-induced chaperone acting upon misfolded proteins in HSE compared with the HENS group.

CONCLUSIONS

Both pathological and adaptive processes are active in skeletal muscle during healthy ageing. Muscle regeneration pathways are activated during healthy ageing, but there is evidence of dysregulation in sarcopenia. In addition, increased cellular stress, with an impaired oxidative-stress and mis-folded protein response (HSPA1A), may be associated with the development of sarcopenia. The in vitro system of young and old myoblasts replicated some of the differences between young and old muscle.

Why intensity is not a bad word: Optimizing health status at any age

Age-related declines in health and function make locomotion increasingly difficult leading to reductions in non-exercise activity thermogenesis (NEAT), skeletal muscle size and strength, and increased adiposity. Exercise is an important strategy to attenuate loss of function through the life cycle. Despite claims to the contrary, high-intensity exercise is important for the prevention of obesity and sarcopenia with advancing age. Therefore, the purpose of this mini-review is to present literature supporting the contention that low volume, high-intensity aerobic and/or resistance training can slow sarcopenia, sustain ease of movement, stimulate NEAT, and attenuate the accretion of fat mass.

Full-layer mucosal histology in achalasia: Histological epithelial wave is characteristic in "pinstripe pattern"-positive achalasia

BACKGROUND

Previously, the mucosal histology in achalasia has only been investigated using superficial biopsy or surgically resected esophageal specimens in end-stage cases. We investigated the histology of the full-layer mucosa in early and advanced achalasia.

METHODS

Endoscopy was performed for the pinstripe pattern (PSP) (an early achalasia indicator) and dilation and thickening of the mucosa (advanced achalasia indicators). A mucosal entry site for peroral endoscopic myotomy was created using cap-fitted endoscopic mucosal resection to access the full-layer mucosa and the submucosa.

KEY RESULTS

Mucosal histology was compared between 32 patients with achalasia and 15 controls. Histological esophagitis with findings of inflammatory cell infiltration and dilated intercellular spaces was observed more in patients with achalasia than in controls (87.5% vs 13.3%, P<.001; 84.4% vs 46.7%, P=.049). Muscularis mucosae (MM) atrophy and epithelial wave were only observed in achalasia (40.6% vs 0%, P=.005; 28.1% vs 0%, P=.043). Fibrosis was more common in achalasia, but without statistical significance (31.3% vs 20.0%, P=.503). In achalasia with endoscopic dilation and thickening of the mucosa, MM atrophy was observed histologically, and in cases involving endoscopic PSP, the histological epithelial wave was observed.

CONCLUSIONS & INFERENCES

Histological findings of esophagitis were observed endoscopically even in early achalasia. Pinstripe pattern corresponds to the epithelial wave observed histologically in achalasia, whereas endoscopic findings in advanced achalasia correspond to MM atrophy. Appropriate management is necessary during early achalasia to prevent progression to advanced achalasia with more severe histological changes.

Muscle Mass, Strength, Mobility, Quality of Life, and Disease Severity in Ankylosing Spondylitis Patients: A Preliminary Study

Objective

To determine if there is muscle mass reduction in patients with ankylosing spondylitis (AS) compared to the general population and to examine the relationship between skeletal muscle mass, quality of life (QOL), strength, and mobility in patients with AS.

Methods

A total of 30 AS patients were enrolled in this study. Skeletal muscle mass was measured by bioelectrical impedance analysis, and it was expressed as the skeletal muscle mass index (SMI). QOL was assessed using the EuroQOL (EQ-5D). To measure mobility, the modified Schöber test and chest expansion test were used. To measure grip strength as a measure of muscle strength, we used the hydraulic hand dynamometer. Additionally, we divided the patients into two groups according to the degree of X-ray finding and compared the differences between the two groups.

Results

There was no significant reduction in skeletal muscle mass in patients with AS compared to the general population. Also, there was no significant correlation between SMI and QOL. On the other hand, there was a significant positive correlation between SMI and mobility, and grip strength. A significant positive correlation was found between mobility and QOL. Additionally, there was a statistically significant difference in mobility between the two groups according to the degree of X-ray finding.

Conclusion

Maintaining muscle mass in AS patients may not be helpful for improving QOL, but it may contribute to achieving adequate mobility and strength.

Nonalcoholic fatty liver disease and sarcopenia in a Western population (NHANES III): The importance of sarcopenia definition

BACKGROUND

Recent epidemiological studies have shown that sarcopenia is associated with non-alcoholic fatty liver disease (NAFLD) and advanced fibrosis in an Asian population. We investigated whether NAFLD is associated with a higher risk of sarcopenia using a different definition in elderly patients.

METHODS

A population-based cross-sectional survey of US patients was conducted, involving 2551 participants aged 60-75 years. NAFLD was measured by ultrasound. Sarcopenia was defined by both a low muscle mass and poor muscle function. In addition, the skeletal muscle index (SMI) was calculated as the absolute muscle mass (kilograms) divided by height² (meters) or total body mass (kilograms). A multivariable logistic regression was conducted to estimate the relationship between sarcopenia and NAFLD in the elderly.

RESULTS

After adjusting for age, sex, and race/ethnicity, severe hepatic steatosis was associated with a decreased risk of sarcopenia as defined by the height-adjusted SMI (odds ratio (OR) 0.63; 95% confidence interval (CI) 0.46-0.87). In contrast, severe hepatic steatosis was associated with an increased risk of sarcopenia as defined by the weight-adjusted SMI (OR 1.73; 95% CI 1.31-2.28). These significant associations remained after further adjustments for other potential confounding variables.

CONCLUSIONS

NAFLD is associated with a lower risk of sarcopenia when using the height-adjusted SMI. In contrast, it showed the opposite result when using the weight-adjusted SMI. The definition of sarcopenia may be an important factor when examining its relationship with NAFLD.

Relationship between major dietary patterns and sarcopenia among menopausal women

BACKGROUND AND AIM

Dietary habits have been associated with the prevalence of the sarcopenia and limited data are available in this field for menopausal women. This study focused on the relationship between dietary patterns and prevalence of the sarcopenia in menopausal women.

METHODS

This cross-sectional study was done in 250 menopausal women 45 years old or older. Dietary data were collected using a food-frequency questionnaire and physical activity was assessed by International Physical Activity Questionnaire (IPAQ). Height, weight, skeletal muscle mass, hand grip, and gait speed were measured and sarcopenia was defined based on European Working Group on Sarcopenia in Older People (EWGSOP) guidelines.

RESULTS

Using factor analysis, two major dietary patterns were found: a Western pattern (high in commercial beverage, sugar and dessert, snacks, solid fat, potato, high fat dairy, legume, organ meat, fast food, and sweets) and a Mediterranean pattern (high in olive, low-fat dairy, vegetable, fish, nut, and vegetable oil). After adjusting for confounding variables, for the highest vs the lowest tertiles, the Odds Ratio (OR) for sarcopenia was 1.06 [95% confidence interval (CI), 0.47-2.37] in the Western pattern and 0.40 [95% confidence interval (CI), 0.17-0.89] in the Mediterranean pattern.

CONCLUSIONS

Our findings suggest that Mediterranean dietary pattern has a favorable role in the prevention of sarcopenia.

What is the impact of the European Consensus on the diagnosis and prevalence of sarcopenia among institutionalized elderly persons?

Abstract Objective: To verify the impact of the European Consensus on the diagnosis and prevalence of sarcopenia among institutionalized elderly persons in Natal, Rio Grande do Norte, Brazil. Method: 219 elderly persons (≥60 years) of both genders were recruited for the study. Two criteria were initially used to calculate the prevalence of sarcopenia: criterion A, based on the European Consensus, considering only elderly persons with good physical and cognitive conditions and criterion B, considering all elderly individuals, regardless of their physical and/or cognitive condition. The association between sarcopenia and gender, age and body mass index (BMI) in the two groups was investigated using the chi-square test and the Student's t-test, with a significance level of 5%. Result: the diagnosis of sarcopenia according to Criterion A revealed a prevalence of 32% (95% CI: 22.54-43.21), whereas Criterion B identified a prevalence of 63.2% (95% CI: 56; 45-69,13). Despite the difference in the prevalence of sarcopenia using the two criteria employed (p<0.001), no differences were observed in terms of the association with gender (p=0.149, p=0.212), BMI (p<0.001, p<0.001), and age (p=0.904, p=353). Conclusion: including only elderly people with good physical and cognitive abilities to calculate sarcopenia, based on the European Consensus, underestimates the prevalence of this condition among institutionalized elderly. As elderly persons with physical or cognitive limitations are extremely typical in the population of care facilities and increased diagnostic calculation for sarcopenia did not interfere with the distribution of associated factors, it is recommended that these individuals are considered in the basis of calculation for future studies of the diagnosis and prevalence of sarcopenia.

Measurement of muscle health in aging

Muscle health is a critical component in the struggle against physical frailty and the efforts to maintain metabolic health until the limit of chronological age. Consensus opinion is to evaluate muscle health in terms of muscle mass, strength and functional capability. There has been considerable variability in the components of muscle health which have been investigated in addition to variability in the tools of assessment and protocol for measurement. This is in stark contrast to the validated measurement of bone health across the adult life span. The purpose of this review was to identify indices of muscle mass, strength and functional capability most responsive to change with ageing and where possible to provide an estimate of the rate of change. We suggest lean tissue mass (LTM) or skeletal muscle (SM) is best evaluated from the thigh region due to its greater responsiveness to ageing compared to the whole body. The anterior compartment of the thigh region undergoes a preferential age-related decline in SM and force generating capacity. Therefore, we suggest that knee extensor torque is measured to represent the force generating capacity of the thigh and subsequently, to express muscle quality (strength per unit tissue). Finally, we suggest measures of functional capability which allow participants perform to a greater maximum are most appropriate to track age-related difference in functional capacity across the adult lifespan. This is due to their ability encompass a broad spectrum of abilities. This review suggests indices of muscular health for which reference ranges can be generated across the lifespan.

Sarcopenia

Sarcopenia is a condition that is characterized by loss of muscle mass, muscle strength and muscle functional impairment with ageing. The definition of sarcopenia has been through various permutations; however, an enormous recent breakthrough is the inclusion of the condition in the ICD-10 classification of diseases. This chapter covers the background issues regarding definition before describing the epidemiology of the disease according to human and environmental factors. It then provides a practical guide for the assessment of sarcopenia in a clinical setting and finishes with advice on present treatment and the exciting frontiers of future therapies.

Functional decline at the aging neuromuscular junction is associated with altered laminin-α4 expression

Laminin-α4 is involved in the alignment of active zones to postjunctional folds at the neuromuscular junction (NMJ). Prior study has implicated laminin-α4 in NMJ maintenance, with altered NMJ morphology observed in adult laminin-α4 deficient mice (lama4^−/−). The present study further investigated the role of laminin-α4 in NMJ maintenance by functional characterization of transmission properties, morphological investigation of synaptic proteins including synaptic laminin-α4, and neuromotor behavioral testing. Results showed maintained perturbed transmission properties at lama4^−/− NMJs from adult (3 months) through to aged (18-22 months). Hind-limb grip force demonstrated similar trends as transmission properties, with maintained weaker grip force across age groups in lama4^−/−. Interestingly, both transmission properties and hind-limb grip force in aged wild-types resembled those observed in adult lama4^−/−. Most significantly, altered expression of laminin-α4 was noted at the wild-type NMJs prior to the observed decline in transmission properties, suggesting that altered laminin-α4 expression precedes the decline of neurotransmission in aging wild-types. These findings significantly support the role of laminin-α4 in maintenance of the NMJ during aging.

MRI-defined paraspinal muscle morphology in Japanese population: The Wakayama Spine Study

OBJECTIVE

This study aimed to establish sex- and age-dependent distributions of the cross sectional area and fatty infiltration ratio of paraspinal muscles, and to examine the correlation between paraspinal muscle degeneration and low back pain in the Japanese population.

METHODS

In this cross-sectional study, data from 796 participants (241 men, 555 women; mean age, 63.5 years) were analyzed. The measurement of the cross sectional area and fatty infiltration ratio of the erector spinae and multifidus from the level of T12/L1 to L4/5 and psoas major at the level of T12/L1 was performed using axial T2-weighted magnetic resonance imaging. Multivariate logistic regression analysis was used to estimate the association between fatty infiltration of the paraspinal muscles and the prevalence of low back pain.

RESULTS

The cross sectional area was larger in men than women, and tended to decrease with age, with the exception of the erector spinae at T12/L1 and L1/2 in women. The fatty infiltration ratio was lower in men than women, except for multifidus at T12/L1 in 70-79 year-olds and psoas major in those less than 50 years-old, and tended to increase with age. Logistic regression analysis adjusted for age, sex, and body mass index showed that the fatty infiltration ratio of the erector spinae at L1/2 and L2/3 was significantly associated with low back pain (L1/2 level: odds ratio, 1.05; 95% confidence interval, 1.005-1.104; L2/3 level: odds ratio, 1.05; 95% confidence interval, 1.001-1.113).

CONCLUSION

This study measured the cross sectional area and fatty infiltration ratio of paraspinal muscles in the Japanese population using magnetic resonance imaging, and demonstrated that the fatty infiltration ratio of the erector spinae in the upper lumbar spine was significantly associated with the presence of low back pain. The measurements could be used as reference values, which are important for future comparative studies.

Body composition by DXA

Body composition measurements from DXA have been available since DXA technology was developed 30years ago, but are historically underutilized. Recently, there have been rapid developments in body composition assessment including the analysis and publication of representative data for the US, official usage guidance from the International Society for Clinical Densitometry, and development of regional body composition measures with clinical utility. DXA body composition is much more than whole body percent fat. In this paper celebrating 30years of DXA for body composition, we will review the principles of DXA soft tissue analysis, practical clinical and research applications, and what to look for in the future.

[Effect of resveratrol on forelimb grip strength and myofibril structure in aged rats]

OBJECTIVE

To observe the effect of resveratrol on muscle mass, forelimb grip strength, myofibril structure and AMPK/sirt1 pathway in skeletal muscles of aged rats.

METHODS

Twenty aged (25 months old) SD rats were randomly divided into aged control group and resveratrol treatment group (10 in each group) with 10 young (6 months old) rats served as the young control group. In resveratrol treatment group, the rats were treated with resveratrol (mixed in chow) for 6 weeks. After the treatment, the mass of the gastrocnemius was measured and the sarcopenia index (SI) was calculated as the gastrocnemius mass (mg) to body weight (g) ratio. The forelimb grip strength of the rats was measured using a electronic grip strength meter, and the lengths of the sarcomere, I-band, A-band and H-zone of the myofibrils were determined by transmission electron microscopy.

RESULTS

Compared with the young rats, the aged control rats had significantly lower SI of the gastrocnemius (P<0.05) and grip strength (P<0.05) with increased lengths of the sarcomere, A-band, I-band and H-zone (P<0.05) and lowered expressions of AMPK, P-AMPK, and sirt1 protein (P<0.05). Resveratrol treatment of the aged rats significantly increased the forelimb grip strength, reduced the lengths of sarcomere length, I-band and H-zone (P<0.05) and increased, P-AMPK, sirt1 protein expressions (P<0.05) without significantly affecting the SI (P>0.05) or the A-band length (P>0.05).

CONCLUSION

Resveratrol does not improve the muscle mass but can increase the forelimb grip strength in aged rats possibly by activating AMPK/sirt1 pathway to improve the ultrastructure of the myofibrils.

Effect of conjugated linoleic acids and omega-3 fatty acids with or without resistance training on muscle mass in high-fat diet-fed middle-aged mice

NEW FINDINGS

What is the central question of this study? This study examined the effects of 20 weeks of administration of conjugated linoleic acids/omega-3 fatty acids with or without programed resistance exercise training on body composition, skeletal muscle properties and functional capacity in middle-aged mice fed a high-fat diet. What is the main finding and its importance? Chronic daily administration of conjugated linoleic acids/omega-3 fatty acids with resistance exercise training can help to blunt fat gain, alleviate loss of myogenic capacity and sensorimotor function and lower tissue inflammation in middle-aged mice during chronic high-fat diet-induced catabolism. This study investigated the effects of 20 weeks of combined conjugated linoleic acid (CLA)/omega-3 fatty acid (n-3) administration independently or combined with resistance exercise training (RET) on skeletal muscle in middle-aged mice consuming a high-fat diet (HFD). Nine-month-old C57BL/6 mice were randomly assigned into four experimental groups (H, high-fat diet; HE, H + RET; HCN, H + CLA/n-3; and HECN, H + CLA/n3 + RET). Body composition and functional capacity were assessed pre- and post-intervention. Muscle tissues were collected at 14 months of age. ANOVA was used, with significance set at P ≤ 0.05. Fat mass significantly increased in H (+74%), HE (+142%) and HECN (+43%) but not in HCN. Muscle wet weights were significantly lower in H and HCN than in HE and HECN. Grip strength substantially declined in H (-15%) and HCN (-17%), whereas sensorimotor function significantly declined only in H (-11%). HECN exhibited improvement in strength (+22%) and sensorimotor coordination (+17%). In comparison to H, muscle tumour necrosis factor-α mRNA expression was significantly lower in HE (-39%), HCN (-24%) and HECN (-21%), respectively. Mean myofibre cross-sectional areas were markedly lower in H and HCN than in HE and HECN. H showed significantly lower satellite cell abundance and numbers of myonuclei than all other groups. Our findings suggest that long-term daily CLA/n-3 intake with resistance training improved sensorimotor function, ameliorated fat gain and prevented loss of myogenic capacity while lowering tumour necrosis factor-α expression during chronic HFD.

Anorexia, functional capacity, and clinical outcome in patients with chronic heart failure: results from the Studies Investigating Co-morbidities Aggravating Heart Failure (SICA-HF)

Aims

We aimed to assess determinants of anorexia, that is loss of appetite in patients with heart failure (HF) and aimed to further elucidate the association between anorexia, functional capacity, and outcomes in affected patients.

Methods and results

We assessed anorexia status among 166 patients with HF (25 female, 66 ± 12 years) who participated in the Studies Investigating Co‐morbidities Aggravating HF. Anorexia was assessed by a 6‐point Likert scale (ranging from 0 to 5), wherein values ≥1 indicate anorexia. Functional capacity was assessed as peak oxygen uptake (peak VO₂), 6 min walk test, and short physical performance battery test. A total of 57 patients (34%) reported any anorexia, and these patients showed lower values of peak VO₂, 6 min walk distance, and short physical performance battery score (all P < 0.05). Using multivariate analysis adjusting for clinically important factors, only high‐sensitivity C‐reactive protein [odds ratio (OR) 1.24, P = 0.04], use of loop diuretics (OR 5.76, P = 0.03), and the presence of cachexia (OR 2.53, P = 0.04) remained independent predictors of anorexia. A total of 22 patients (13%) died during a mean follow‐up of 22.5 ± 5.1 months. Kaplan‐Meier curves for cumulative survival showed that those patients with anorexia presented higher mortality (Log‐rank test P = 0.03).

Conclusions

Inflammation, use of loop diuretics, and cachexia are associated with an increased likelihood of anorexia in patients with HF, and patients with anorexia showed impaired functional capacity and poor outcomes.

Increased plasma proline concentrations are associated with sarcopenia in the elderly

Background and purpose

Metabolome analyses have shown that plasma amino acid profiles reflect various pathological conditions, such as cancer and diabetes mellitus. It remains unclear, however, whether plasma amino acid profiles change in patients with sarcopenia. This study therefore aimed to investigate whether sarcopenia-specific changes occur in plasma amino acid profiles.

Methods

A total of 153 community-dwelling and seven institutionalized elderly individuals (56 men, 104 women; mean age, 77.7±7.0 years) were recruited for this cross-sectional analysis. We performed a comprehensive geriatric assessment, which included an evaluation of hand grip strength, gait speed, muscle mass and blood chemistry, including the concentration of 18 amino acids.

Results

Twenty-eight of the 160 participants met the criteria for sarcopenia established by the Asian Working Group on Sarcopenia in Older People. Univariate analysis revealed associations between the presence of sarcopenia and a higher plasma concentration of proline and glutamine, lower concentrations of histidine and tryptophan. Multivariable analysis revealed that a higher concentration of proline was the only variable independently associated with sarcopenia.

Conclusions

The plasma concentration of proline may be useful for understanding the underlying pathophysiology of sarcopenia.

The Combination of Physical Exercise with Muscle-Directed Antioxidants to Counteract Sarcopenia: A Biomedical Rationale for Pleiotropic Treatment with Creatine and Coenzyme Q10

Sarcopenia represents an increasing public health risk due to the rapid aging of the world's population. It is characterized by both low muscle mass and function and is associated with mobility disorders, increased risk of falls and fractures, loss of independence, disabilities, and increased risk of death. Despite the urgency of the problem, the development of treatments for sarcopenia has lagged. Increased reactive oxygen species (ROS) production and decreased antioxidant (AO) defences seem to be important factors contributing to muscle impairment. Studies have been conducted to verify whether physical exercise and/or AOs could prevent and/or delay sarcopenia through a normalization of the etiologically relevant ROS imbalance. Despite the strong rationale, the results obtained were contradictory, particularly with regard to the effects of the tested AOs. A possible explanation might be that not all the agents included in the general heading of "AOs" could fulfill the requisites to counteract the complex series of events causing/accelerating sarcopenia: the combination of the muscle-directed antioxidants creatine and coenzyme Q10 with physical exercise as a biomedical rationale for pleiotropic prevention and/or treatment of sarcopenia is discussed.

Towards ageing well: Use it or lose it: Exercise, epigenetics and cognition

More and more people are living into the 90s or becoming centenarians. But, the gift of increased ‘age span’ seldom equates with an improved ‘health-span’. Governments across the world are expressing concern about the epidemic of chronic disease, and have responded by initiating policies that make prevention, reduction and treatment of chronic disease, a public health priority. But understanding, how to age long and well, with the avoidance of chronic disease and later life complex disease morbidity is challenging. While inherited genes have an undoubted role to play in the chance of maintaining good health or conversely a predilection to developing disease and chronic ill health, there is increasing evidence that behavioural and environmental life-style choices may contribute up to 50% of the variability of human lifespan. Physical exercise is readily available to everyone, and is a simple cheap and effective form of life-style intervention. Exercise appears to help maintain good health and to reduce the risk of developing chronic disease and ill health. Evidence suggests that physical activity improves well-being across many health domains through out life, continues to offer important health benefits in older age groups and tracks with a ‘healthy ageing’ profile. Although many of the molecular pathways remain to be fully identified, here we discuss how physical activity and exercise is understood to produce changes in the human epigenome, which have the potential to enhance cognitive and psychological health, improve muscular fitness, and lead to better ageing with improved quality of life in older age.

Higher uric acid serum levels are associated with better muscle function in the oldest old: Results from the Mugello Study

BACKGROUND

Sarcopenia is the progressive loss of muscle mass and strength that occurs with advancing age and plays a pivotal role in the causal pathway leading to frailty, disability and, eventually, to death among older persons. As oxidative damage of muscle proteins has been shown to be a relevant contributory factor, in this study we hypothesized that uric acid (UA), a powerful endogenous antioxidant, might exert a protective effect on muscle function in the oldest old and we tested our hypothesis in a group of nonagenarians who participated in the Mugello Study.

METHODS

239 subjects, 73 men and 166 women, mean age 92.8years±SD 3.1, underwent the assessment of UA serum level and isometric handgrip strength, a widely used clinical measure of sarcopenia.

RESULTS

Mean UA serum level was 5.69mg/dL±SD 1.70 and mean handgrip strength was 15.0kg±SD 6.9. After adjusting for relevant confounders, higher UA serum levels remained independent positive predictors of isometric handgrip strength (β 1.24±SE(β) 0.43, p=0.005).

CONCLUSION

Our results show that higher UA serum levels are associated with better muscle function in the oldest old and, accordingly, might slow down the progression of sarcopenia.

Radiographic sarcopenia predicts postoperative infectious complications in patients undergoing pancreaticoduodenectomy

BACKGROUND

Recently, skeletal muscle depletion (sarcopenia) has been reported to influence postoperative outcomes after certain procedures. This study investigated the impact of sarcopenia on postoperative outcomes following pancreaticoduodenectomy (PD).

METHODS

We performed a retrospective study of consecutive patients (n = 219) who underwent PD at our institution between January 2007 and May 2013. Sarcopenia was evaluated using preoperative computed tomography. We evaluated postoperative outcomes and the influence of sarcopenia on short-term outcomes, especially infectious complications. Subsequently, multivariate analysis was used to assess the impact of prognostic factors (including sarcopenia) on postoperative infections.

RESULTS

The mortality, major complication, and infectious complication rates for all patients were 1.4%, 16.4%, and 47.0%, respectively. Fifty-five patients met the criteria for sarcopenia. Sarcopenia was significantly associated with a higher incidence of in-hospital mortality (P = 0.004) and infectious complications (P < 0.001). In multivariate analyses, sarcopenia (odds ratio = 3.43; P < 0.001), preoperative biliary drainage (odds ratio = 2.20; P = 0.014), blood loss (odds ratio = 1.92; P = 0.048), and soft pancreatic texture (odds ratio = 3.71; P < 0.001) were independent predictors of postoperative infections.

CONCLUSIONS

Sarcopenia is an independent preoperative predictor of infectious complications after PD. Clinical assessment combined with sarcopenia may be helpful for understanding the risk of postoperative outcomes and determining perioperative management strategies.

Vitamin B12 deficiency might be related to sarcopenia in older adults

Sarcopenia and dynapenia are related to repeated falls, mobility restriction, depression, frailty, increased mortality and morbidity. The aim of this study is to evaluate the relationship between vitamin B12 deficiency and sarcopenia in older adults. 403 patients, who attended to outpatient clinic and underwent comprehensive geriatric assessment, were included study. All cases' skeletal muscle mass (SMM), walking speed and hand grip strength were recorded by bioimpedance, 4meter walking test and hand dynamometer respectively. The diagnosis of sarcopenia was defined according to the criteria of the European Working Group on Sarcopenia in Older People. Sarcopenia was accepted low SMM with low handgrip strength or low physical performance. Dynapenia was defined as handgrip strength <30kg (men) and <20kg (women). The prevalence of sarcopenia and dynapenia was 24.8% and 32.0%, respectively. In the patients with sarcopenia, mean age, osteoporosis and frailty were higher, and MMSE, and instrumental ADL scores were lower than the patients without sarcopenia (p<0.05). The frequency of sarcopenia and dynapenia were 31.6% and 35.4%, respectively, in patients with vitamin B12 levels <400pg/mL. In addition lean body mass, total skeletal mass and skeletal muscle mass index were lower in the patients with vitamin B12 levels <400pg/mL compared to higher than 400pg/mL (p<0.05). Sarcopenia, which results in lots of negative clinical outcomes in older adults, might be related to vitamin B12 deficiency. Therefore, these patients should be periodically examined for vitamin B12 deficiency due to the potential negative clinical outcomes such as sarcopenia in older adults.

Association between body composition parameters and risk of mild cognitive impairment in older Japanese adults

AIM

The aim of the present study was to investigate the association between various body composition parameters and the risk of mild cognitive impairment (MCI) in older Japanese adults, as well as potential sex-related differences in the risk of MCI.

METHODS

Participants underwent cognitive tests, and were divided into 840 participants with MCI (mean age 71.9 ± 5.5 years) and 1740 without MCI (mean age 71.3 ± 5.2 years). Body composition parameters were measured using a bioelectrical impedance analyzer. Multiple logistic regression analysis was then carried out to examine the associations between body composition parameters and risk of MCI.

RESULTS

After adjusting for confounding factors, those in the lowest quartile for fat-free mass had a higher risk of MCI than those in the highest quartile (men: odds ratio [OR] 1.96, 95% confidence interval CI 1.24-3.10; women: OR 1.49, 95% CI 1.01-2.19). Loss of muscle mass in the upper (OR 2.17, 95% CI 1.40-3.37) and lower (OR 1.99, 95% CI 1.25-3.15) limbs was associated with a higher MCI risk in men. However, only loss of muscle mass in the lower limbs was associated with a higher MCI risk (OR 1.61, 95% CI 1.06-2.44) in women. No associations were found between obesity measures and MCI.

CONCLUSIONS

We found that loss of fat-free mass was associated with MCI in older adults, regardless of sex. We also found that appendicular muscle mass was more closely associated with MCI in men than in women. These results suggest that the association between appendicular muscle mass and MCI might have different underlying mechanisms based on sex. Geriatr Gerontol Int 2017; 17: 2053-2059.

Heart Failure with Preserved Ejection Fraction in Older Adults

Most elderly patients, particularly women, who have heart failure, have a preserved ejection fraction. Patients with this syndrome have severe symptoms of exercise intolerance, frequent hospitalizations, and increased mortality. Despite the importance of heart failure with preserved ejection fraction (HFpEF), the understanding of its pathophysiology is incomplete, and optimal treatment remains largely undefined. Unlike the management of HFrEF, there is a paucity of large evidence-based trials demonstrating morbidity and mortality benefit for the treatment of HFpEF. An update is presented on information regarding pathophysiology, diagnosis, management, and future directions in this important and growing disorder.

Circulating cell-free nucleic acids as potential biomarkers for sarcopenia: a step toward personalized medicine

Sarcopenia is an age-related loss of muscle mass and function, leading to disability, morbidity and increased mortality in older people. Given the relatively high prevalence and related- outcome of the disease, correct diagnosis, screening, monitoring and treatment of sarcopenia are needed in clinical practice. Recent researches have focused on cell-free nucleic acids, which are released into the circulation following cell death, as a potential biomarker of aging and systematic inflammation. It seems that the diagnosis and treatment of sarcopenia can be possible by the help of the analysis of cell-free nucleic acids as noninvasive method.

Relationships among Obesity, Sarcopenia, and Osteoarthritis in the Elderly

Background

The present study examined the correlations between obesity, sarcopenia, and osteoarthritis in Korea’s elderly population.

Methods

A cross-sectional analysis of 1,865 and 1,769 respondents with knee osteoarthritis and lumbar spondylosis, respectively, was performed by using data from the 2010 and 2011 Korea National Health and Nutrition Examination Survey. Obesity was defined as a body mass index of ≥25 kg/m²; osteoarthritis, as a Kellgren/Lawrence grade of ≥2; and sarcopenia, as an appendicular skeletal muscle mass (ASM; ASM/weight ×100) on dual-energy X-ray absorptiometry of two standard deviations below the mean reference value.

Results

The unadjusted and age-adjusted risks of knee osteoarthritis were as follows: 1.88 and 1.92 times greater, respectively, for male subjects with sarcopenic obesity; 6.03 and 7.64 times greater, respectively, for female subjects with non-sarcopenic obesity; and 1.97 and 2.43 times greater, respectively, for female subjects with sarcopenic obesity. The age-and-waist circumference-adjusted risks were 5.88 and 1.80 times greater for the female subjects with non-sarcopenic and sarcopenic obesities, respectively. No statistically significant finding was obtained for lumbar spondylosis.

Conclusion

Obesity and sarcopenia were associated with knee osteoarthritis in the elderly subjects. The risk of knee osteoarthritis was greater in the male subjects with sarcopenic obesity than in the male subjects with non-sarcopenic obesity. In the female subjects, the risk of knee osteoarthritis was high in both obesity groups. Further research to explain the sex-related difference in knee osteoarthritis risk based on body composition will be beneficial.

Changes in physical activity, sedentary time, and risk of falling: The Women's Health Initiative Observational Study

Falling significantly affects quality of life, morbidity, and mortality among older adults. We sought to evaluate the prospective association between sedentary time, physical activity, and falling among post-menopausal women aged 50-79years recruited to the Women's Health Initiative Observational Study between 1993 and 1998 from 40 clinical centers across the United States. Baseline (B) and change in each of the following were evaluated at year 3 (Y3) and year 6 (Y6; baseline n=93,676; Y3 n=76,598; Y6 n=75,428): recreational physical activity (MET-h/wk), sitting, sleeping (min/day), and lean body mass by dual energy X-ray absorptiometry (subset N=6475). Falls per year (0, 1, 2, ≥3) were assessed annually by self-report questionnaire and then dichotomized as ≤1 and ≥2falls/year. Logistic regression models were adjusted for demographics, body mass index, fall history, tobacco and alcohol use, medical conditions, and medications. Higher baseline activity was associated with greater risk of falling at Y6 (18%; p for trend <0.0001). Increasing sedentary time minimally decreased falling (1% Y3; 2% Y6; p<0.05). Increasing activity up to ≥9MET-h/wk. (OR: 1.12, 95% CI: 1.03-1.22) or maintaining ≥9MET-h/wk. (OR: 1.20, 95% CI: 1.13-1.29) increased falling at Y3 and Y6 (p for trend <0.001). Adding lean body mass to the models attenuated these relationships. Physically active lifestyles increased falling among post-menopausal women. Additional fall prevention strategies, such as balance and resistance training, should be evaluated to assist post-menopausal women in reaching or maintaining levels of aerobic activity known to prevent and manage several chronic diseases.

Dihydrotestosterone treatment rescues the decline in protein synthesis as a result of sarcopenia in isolated mouse skeletal muscle fibres

BACKGROUND

Sarcopenia, the progressive decline in skeletal muscle mass and function with age, is a debilitating condition. It leads to inactivity, falls, and loss of independence. Despite this, its cause(s) and the underlying mechanism(s) are still poorly understood.

METHODS

In this study, small skeletal muscle fibre bundles isolated from the extensor digitorum longus (a fast-twitch muscle) and the soleus (a slow-twitch muscle) of adult mice of different ages (range 100-900 days old) were used to investigate the effects of ageing and dihydrotestosterone (DHT) treatment on protein synthesis as well as the expression and function of two amino acid transporters; the sodium-coupled neutral amino acid transporter (SNAT) 2, and the sodium-independent L-type amino-acid transporter (LAT) 2.

RESULTS

At all ages investigated, protein synthesis was always higher in the slow-twitch than in the fast-twitch muscle fibres and decreased with age in both fibre types. However, the decline was greater in the fast-twitch than in the slow-twitch fibres and was accompanied by a reduction in the expression of SNAT2 and LAT2 at the protein level. Again, the decrease in the expression of the amino acid transporters was greater in the fast-twitch than in the slow-twitch fibres. In contrast, ageing had no effect on SNAT2 and LAT2 expressions at the mRNA level. Treating the muscle fibre bundles with physiological concentrations (~2 nM) of DHT for 1 h completely reversed the effects of ageing on protein synthesis and the expression of SNAT2 and LAT2 protein in both fibre types.

CONCLUSION

From the observations that ageing is accompanied by a reduction in protein synthesis and transporter expression and that these effects are reversed by DHT treatment, we conclude that sarcopenia arises from an age-dependent reduction in protein synthesis caused, in part, by the lack of or by the low bioavailability of the male sex steroid, DHT.

Guidelines for screening and management of late and long-term consequences of myeloma and its treatment

A growing population of long-term survivors of myeloma is now accumulating the 'late effects' not only of myeloma itself, but also of several lines of treatment given throughout the course of the disease. It is thus important to recognise the cumulative burden of the disease and treatment-related toxicity in both the stable and active phases of myeloma, some of which is unlikely to be detected by routine monitoring. We summarise here the evidence for the key late effects in long-term survivors of myeloma, including physical and psychosocial consequences (in Parts 1 and 2 respectively), and recommend the use of late-effects screening protocols in detection and intervention. The early recognition of late effects and effective management strategies should lead to an improvement in the management of myeloma patients, although evidence in this area is currently limited and further research is warranted.

Decreasing skeletal muscle as a risk factor for mortality in elderly patients with sepsis: a retrospective cohort study

Background

Older patients account for the majority of patients with sepsis. The objective of this study was to determine if decreased skeletal muscle mass is associated with outcomes in elderly patients with sepsis.

Methods

Patients (60 years and older) who were admitted to a tertiary medical center intensive care unit with a primary diagnosis of sepsis between January 2012 and February 2016 were included. Patients who had not undergone abdominal computed tomography on the day of admission, had cardiopulmonary arrest on arrival, or had iliopsoas abscess were excluded from the analyses. Cross-sectional muscle area at the 3rd lumber vertebra was quantified, and the relation to in-hospital mortality was analyzed. Multivariable logistic regression analysis that included sex and APACHE II score as explanatory variables was performed. The optimal cutoff value to define decreased muscle mass (sarcopenia) was calculated using receiver operating characteristic curve analysis, and the odds ratio for in-hospital mortality was determined.

Results

There were 150 elderly patients with sepsis (median age, 75 years) enrolled; in-hospital mortality and median APACHE II score were 38.7 and 24%, respectively. The skeletal muscle area of deceased patients was significantly lower than that of the survival group (P < 0.001). The multivariable logistic regression analysis demonstrated that decreased muscle mass was significantly associated with increased mortality (odds ratio = 0.94, 95% confidence interval = 0.90 to 0.97, P < 0.001). The optimal cutoff value of skeletal muscle area to predict in-hospital mortality was 45.2 cm² for men and 39.0 cm² for women. With these cutoff values, the adjusted odds ratio for decreased muscle area was 3.27 (95% CI, 1.61 to 6.63, P = 0.001).

Conclusions

Less skeletal muscle mass is associated with higher in-hospital mortality in elderly patients with sepsis. The results of this study suggest that identifying patients with low muscularity contributes to better stratification in this population.

Muscle mass is associated with incident fracture in postmenopausal women: The OFELY study

The relationships between body composition and bone mineral density are well established but the contribution of body composition to the risk of fracture (Fx) has rarely been evaluated prospectively. We analyzed the risk of Fx by body composition in 595 postmenopausal women (mean age 66±8years) from a longitudinal cohort study (Os des Femmes de Lyon). We assessed the risk of the first incident fragility Fx according to body composition obtained from whole-body DXA: abdominal visceral (VFAT) and subcutaneous fat mass (SFAT), total body fat mass (FM), lean mass index (LMI) and appendicular skeletal muscle mass index (ASMI). During a median [IQ] follow-up of 13.1years [1.9], 138 women sustained a first incident Fx, including 85 women with a major osteoporotic Fx (MOP Fx: hip, clinical spine, humerus or wrist). After adjustment for age, women who sustained Fx had lower BMI (-4%, p=0.01), LMI (-6%, p=0.002) and ASMI (-3%, p=0.003), compared with women without Fx. After adjustment for age, prevalent Fx, physical activity, incident falls and FN BMD, each SD increase of baseline values of LMI and ASMI was associated with decreased Fx risk with adjusted hazard ratios of 0.76 for both of p≤0.02. Those associations were similar after accounting for the competing risk of death. VFAT and SFAT were associated with Fx risk in the multivariate model only for MOP Fx and the association did not persist after consideration of competing mortality. We conclude that lean mass and appendicular muscle mass indexes are associated with the risk of fracture in postmenopausal women independently of BMD and clinical risk factors.

Omega-3 Fatty Acids and Vitamin D in Immobilisation: Part B- Modulation of Muscle Functional, Vascular and Activation Profiles

OBJECTIVES

This study set out to determine whether two potential protein-sparing modulators (eicosapentaenoic acid and vitamin D) would modulate the anticipated muscle functional and related blood vessels function deleterious effects of immobilisation.

DESIGN

The study used a randomised, double-blind, placebo-controlled design.

SETTING

The study took part in a laboratory setting.

PARTICIPANTS

Twenty-four male and female healthy participants, aged 23.0±5.8 years.

INTERVENTION

The non-dominant arm was immobilised in a sling for a period of nine waking hours a day over two continuous weeks. Participants were randomly assigned to one of three groups: placebo (n=8, Lecithin, 2400 mg daily), omega-3 (ω-3) fatty acids (n=8, eicosapentaenoic acid (EPA); 1770 mg, and docosahexaenoic acid (DHA); 390 mg, daily) or vitamin D (n=8, 1,000 IU daily).

MEASUREMENTS

Isometric and isokinetic torque, antagonist muscle co-contraction (activation profile), muscle fatigability indices, and arterial resting blood flow were measured before, at the end of the immobilisation period, and two weeks after re-mobilisation.

RESULTS

Muscle elbow flexion and extension isometric and isokinetic torque decreased significantly with limb immobilisation in the placebo group (P<0.05). Despite no significant effect of supplementation, ω-3 and vitamin D supplementation showed trends (P>0.05) towards attenuating the decreases observed in the placebo group. There was no significant change in muscle fatigue parameters or co-contraction values with immobilisation and no effect of supplementation group (P>0.05). Similarly, this immobilisation model had no impact on the assessed blood flow characteristics. All parameters had returned to baseline values at the re-mobilisation phase of the study.

CONCLUSION

Overall, at the current doses, neither ω-3 nor vitamin D supplementation significantly attenuated declines in torque associated with immobilisation. It would appear that muscle function (described here in Part B) might not be as useful a marker of the effectiveness of a supplement against the impact of immobilisation compared to tissue composition changes (described in Part A).

Is osteoporosis a predictor for future sarcopenia or vice versa? Four-year observations between the second and third ROAD study surveys

In a 4-year follow-up study that enrolled 1099 subjects aged ≥60 years, sarcopenia prevalence was estimated at 8.2%. Moreover, the presence of osteoporosis was significantly associated with short-term sarcopenia occurrence, but the reciprocal relationship was not observed, suggesting that osteoporosis would increase the risk of osteoporotic fracture and sarcopenia occurrence.

INTRODUCTION

The present 4-year follow-up study was performed to clarify the prevalence, incidence, and relationships between sarcopenia (SP) and osteoporosis (OP) in older Japanese men and women.

METHODS

We enrolled 1099 participants (aged, ≥60 years; 377 men) from the second survey of the Research on Osteoarthritis/Osteoporosis against Disability (ROAD) study (2008-2010) and followed them up for 4 years. Handgrip strength, gait speed, skeletal muscle mass, and bone mineral density were assessed. SP was defined according to the Asian Working Group for Sarcopenia. OP was defined based on the World Health Organization criteria.

RESULTS

SP prevalence was 8.2% (men, 8.5%; women, 8.0%) in the second survey. In those with SP, 57.8% (21.9%; 77.6%) had OP at the lumbar spine L2-4 and/or femoral neck. SP cumulative incidence was 2.0%/year (2.2%/year; 1.9%/year). Multivariate regression analysis revealed that OP was significantly associated with SP occurrence within 4 years (odds ratio, 2.99; 95% confidence interval, 1.46-6.12; p < 0.01), but the reciprocal relationship was not significantly observed (2.11; 0.59-7.59; p = 0.25).

CONCLUSIONS

OP might raise the short-term risk of SP incidence. Therefore, OP would not only increase the risk for osteoporotic fracture but may also increase the risk for SP occurrence.