Prevalence of low muscle mass and associated factors in community-dwelling older adults in Singapore

Prevalence of low calf circumference in hospitalized patients classified by raw or body mass index-adjusted values

BACKGROUND

Adiposity can influence the estimation of muscle mass using calf circumference (CC) and underestimate the frequency of low CC. An adjustment for CC using body mass index (BMI) was proposed to reduce this effect. We aimed to compare the low CC frequency in hospitalized patients when considering raw and BMI-adjusted values and explore data by sex, age, and race (white and non-white).

METHODS

Secondary analysis from two cohort studies conducted with adult hospitalized patients using BMI and CC data collected in the first 72 h after hospital admission. We classified low CC by two approaches: (1) raw CC; (2) BMI-adjusted CC for patients with BMI ≥ 25. Cutoff values for low CC were ≤34 cm (men) and ≤33 cm (women).

RESULTS

Among 1272 patients (54.1 ± 15.3 years old; 51.7% women; 82.1% White race), low CC frequency was 30.6% and low BMI-adjusted CC was 68.9%. For all elevated BMI categories, the low CC frequency was higher when considering BMI-adjusted values (P < 0.001). Low CC was more frequent (P < 0.001) in older adults (38.7% by raw; 79.1% by BMI-adjusted value) than in younger adults (27.6% by raw; 65.2% by BMI-adjusted value) and it was not associated with race. Low CC by raw values was more frequent in men than in women (35.0% versus 26.4%; P = 0.001), but did not differ between sexes when classified by BMI-adjusted values (70.7% versus 67.1%; P = 0.184).

CONCLUSION

Low CC BMI adjusted was 2.2 times more frequent in comparison with raw CC values, and it was identified in >60% of patients with BMI ≥ 25.

Potential of Lycii Radicis Cortex as an Ameliorative Agent for Skeletal Muscle Atrophy

Lycii Radicis Cortex (LRC) is a traditional medicine in East Asia with various beneficial effects, including antioxidant, anti-inflammatory, anti-tumor, anti-diabetic, and anti-depressant properties. However, its potential effects on skeletal muscle atrophy have not been studied. In this study, the protective effects of LRC extract (LRCE) on dexamethasone (DEX)-induced muscle atrophy were investigated in C2C12 myotubes and mice. We evaluated the effect of LRCE on improving muscle atrophy using a variety of methods, including immunofluorescence staining, quantitative polymerase chain reaction (qPCR), Western blot, measurements of oxidative stress, apoptosis, ATP levels, and muscle tissue analysis. The results showed that LRCE improved myotube diameter, fusion index, superoxide dismutase (SOD) activity, mitochondrial content, ATP levels, expression of myogenin and myosin heavy chain (MHC), and reduced reactive oxygen species (ROS) production in dexamethasone-induced C2C12 myotubes. LRCE also enhanced protein synthesis and reduced protein degradation in the myotubes. In mice treated with DEX, LRCE restored calf thickness, decreased mRNA levels of muscle-specific RING finger protein 1 (MuRF1) and atrogin-1, and increased insulin-like growth factor 1 (IGF-1) mRNA level. Moreover, LRCE also repaired gastrocnemius muscle atrophy caused by DEX. Although human studies are not available, various preclinical studies have identified potential protective effects of LRCE against muscle atrophy, suggesting that it could be utilized in the prevention and treatment of muscle atrophy.

Impact of a specialized oral nutritional supplement on quality of life in older adults following hospitalization: Post-hoc analysis of the NOURISH trial

BACKGROUND & AIMS

Both during and after hospitalization, nutritional care with daily intake of oral nutritional supplements (ONS) improves health outcomes and decreases risk of mortality in malnourished older adults. In a post-hoc analysis of data from hospitalized older adults with malnutrition risk, we sought to determine whether consuming a specialized ONS (S-ONS) containing high protein and beta-hydroxy-beta-methylbutyrate (HMB) can also improve Quality of Life (QoL).

METHODS

We analyzed data from the NOURISH trial-a randomized, placebo-controlled, multi-center, double-blind study conducted in patients with congestive heart failure, acute myocardial infarction, pneumonia, or chronic obstructive pulmonary disease. Patients received standard care + S-ONS or placebo beverage (target 2 servings/day) during hospitalization and for 90 days post-discharge. SF-36 and EQ-5D QoL outcomes were assessed at 0-, 30-, 60-, and 90-days post-discharge. To account for the missing QoL observations (27.7%) due to patient dropout, we used multiple imputation. Data represent differences between least squares mean (LSM) values with 95% Confidence Intervals for groups receiving S-ONS or placebo treatments.

RESULTS

The study population consisted of 622 patients of mean age ±standard deviation: 77.9 ± 8.4 years and of whom 52.1% were females. Patients consuming placebo had lower (worse) QoL domain scores than did those consuming S-ONS. Specifically for the SF-36 health domain scores, group differences (placebo vs S-ONS) in LSM were significant for the mental component summary at day 90 (-4.23 [-7.75, -0.71]; p = 0.019), the domains of mental health at days 60 (-3.76 [-7.40, -0.12]; p = 0.043) and 90 (-4.88 [-8.41, -1.34]; p = 0.007), vitality at day 90 (-3.33 [-6.65, -0.01]; p = 0.049) and social functioning at day 90 (-4.02 [-7.48,-0.55]; p = 0.023). Compared to placebo, differences in LSM values for the SF-36 general health domain were significant with improvement in the S-ONS group at hospital discharge and beyond: day 0 (-2.72 [-5.33, -0.11]; p = 0.041), day 30 (-3.08 [-6.09, -0.08]; p = 0.044), day 60 (-3.95 [-7.13, -0.76]; p = 0.015), and day 90 (-4.56 [-7.74, -1.38]; p = 0.005).

CONCLUSIONS

In hospitalized older adults with cardiopulmonary diseases and evidence of poor nutritional status, daily intake of S-ONS compared to placebo improved post-discharge QoL scores for mental health/cognition, vitality, social functioning, and general health. These QoL benefits complement survival benefits found in the original NOURISH trial analysis.

CLINICAL TRIAL REGISTRATION

NCT01626742.

Suitable ultrasound screening method for older adults with disability to identify low muscle mass

Objective

This study aimed to investigate the accuracy and consistency of different ultrasound protocols for the measurement of gastrocnemius muscle (GM) thickness and to identify a suitable ultrasound scheme that can be used to detect the low muscle mass in older with disability.

Materials and methods

In this cross-sectional study, each participant underwent three different ultrasound protocols for the measurement of the GM thickness, and each measurement was repeated three times. The three measurement schemes were as follows: method A, lying on the examination bed in a prone position with legs stretched and relaxed and feet hanging outside the examination bed; method B, lateral right side lying position with legs separated (left leg flexed and right leg in a relaxed state); and method C, right side lying position with legs together and lower limb muscles in a relaxed state. The low muscle mass was determined by averaging two or three measurements of the GM thickness determined using different sonographic protocols.

Results

The study included 489 participants. The difference in the prevalence of low muscle mass identified between two and three replicates of the same measurement protocol ranged from 0 to 1.3%. Considering the three repeated measurements of the method A as the reference, the area under the curve (AUC) in different measurement schemes were 0.977-1 and 0.973-1 in males and females, respectively. Furthermore, male and female Kappa values from low to high were 0.773, 0.801, 0.829, 0.839, and 0.967 and 0.786, 0.794, 0.804, 0.819, and 0.984, respectively.

Conclusion

Different ultrasound measurement protocols showed high accuracy and consistency in identifying low muscle mass. Repeating the measurements two or three times was found to be feasible.

A Body Shape Index and Its Changes in Relation to All-Cause Mortality among the Chinese Elderly: A Retrospective Cohort Study

Although recent evidence has revealed that a body shape index (ABSI) is correlated with the incidence of death among different ethnicities, there remains a paucity of studies investigating the impact of ABSI on mortality within the Chinese elderly. Our objective was to ascertain the link between ABSI, as well as its alterations over time, and all-cause mortality among Chinese aged 65 y and above. A total of 3789 participants were enrolled from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Cox regressions and restricted cubic splines were employed to assess the association of ABSI and relative changes with all-cause mortality. When nonlinearity was detected, a restricted cubic spline regression was subsequently conducted to compute hazard ratios and 95% confidence intervals. The median survival time was 46 months, and 1342 individuals (35.4%) were reported to have died. ABSI contributed independently to rising death rates among Chinese old populations according to univariate and multivariate Cox regressions. Statistically significant associations were also found stratified by age, sex, and lifestyle. A U-shaped association of ABSI changes with all-cause mortality (p = 0.027) was observed, indicating that old adults with stable ABSI during the follow-up period experienced the lowest risk of mortality. After multivariable adjustment, participants with a 10% reduction in ABSI changes had an increased 9.4% risk of death, while participants with a 10% rise in ABSI changes had an increased 1.9% risk. ABSI and its changes are predictors for all-cause mortality among the elderly Chinese population, which emphasizes the clinical importance of monitoring ABSI and keeping it stable over time.

Good nutrition across the lifespan is foundational for healthy aging and sustainable development

Ensuring healthy lives and promoting wellbeing across the age spectrum are essential to sustainable development. Nutrition is at the heart of the World Health Organization (WHO) Sustainable Development Goals, particularly for Sustainable Development Goal 2/Subgoal 2, which is to End all forms of malnutrition by 2030. This subgoal addresses people of all ages, including targeted groups like young children and older adults. In recent decades, there have been marked advances in the tools and methods used to screen for risk of malnutrition and to conduct nutritional assessments. There have also been innovations in nutritional interventions and outcome measures related to malnutrition. What has been less common is research on how nutritional interventions can impact healthy aging. Our Perspective article thus takes a life-course approach to consider what is needed to address risk of malnutrition and why, and to examine how good nutrition across the lifespan can contribute to healthy aging. We discuss broad-ranging yet interdependent ways to improve nutritional status worldwide-development of nutritional programs and policies, incorporation of the best nutrition-care tools and methods into practice, provision of professional training for quality nutritional care, and monitoring health and economic benefits of such changes. Taken together, our Perspective aims to (i) identify current challenges to meeting these ideals of nutritional care, and to (ii) discover enabling strategies for the improvement of nutrition care across the lifespan. In harmony with the WHO goal of sustainable development, we underscore roles of nutrition to foster healthy human development and healthy aging worldwide.

Prevalence and associated factors of sarcopenia in community-dwelling older adults at risk of malnutrition

BACKGROUND

There is an increasingly strong association between sarcopenia and malnutrition in research findings. We aimed to determine the prevalence and factors associated with sarcopenia in community-dwelling older adults (≥ 65 years) at risk of malnutrition based on Malnutrition Universal Screening Tool (MUST).

METHODS

This was a cross-sectional study of 811 participants. Participants were recruited from the general population, community centers, senior activity centers, polyclinics, and hospital. Community-dwelling older adults at risk of malnutrition participated in the study. Participants' data and measurements were collected at the baseline visit. Data included socio-demographic information, anthropometric measurements, body composition, dietary intakes, and functional assessments. Sarcopenia was defined using the Asian Working Group for Sarcopenia 2019 consensus.

RESULTS

Of the 694 participants with complete datasets, overall prevalence of sarcopenia was 76% (n = 530); 57% (n = 393) had severe sarcopenia. In the overall cohort, compared to participants without sarcopenia, those with sarcopenia were older, had lower physical activity scale for the elderly score, leg strength, handgrip endurance, mid-upper arm circumference, calf circumference, and bone mass, and had lower dietary protein intake and poorer nutritional status (all p ≤ 0.015). After adjusting for confounders, sarcopenia was significantly associated with older age, male gender, higher risk of malnutrition, lower calf circumference, and lower bone mass (all p ≤ 0.044).

CONCLUSIONS

In community-dwelling older adults at risk of malnutrition, there is a high prevalence of sarcopenia and severe sarcopenia. As such, screening positive for either malnutrition risk or sarcopenia in older adults should prompt screening for the other risk factor, to allow early institution of disease modifying interventions to forestall adverse outcomes for both malnutrition and sarcopenia.

TRIAL REGISTRATION

The study was registered at clinicaltrials.gov as NCT03245047 .

External validation of BIA equations to estimate appendicular skeletal muscle mass in older adults: Importance of the bias analysis and derivation of correction factors to achieve agreement

There are several equations based on bioelectrical impedance analysis (BIA) to estimate with high precision appendicular skeletal muscle mass (ASM). However, most of the external validation studies have reported that these equations are inaccurate or biased when applied to different populations. Furthermore, none of the published studies has derived correction factors (CFs) in samples of community-dwelling older adults, and none of the published studies have assessed the influence of the dual-energy X-ray absorptiometry (DXA) model on the validation process. This study assessed the agreement between six BIA equations and DXA to estimate ASM in non-Caucasian older adults considering the DXA model and proposed a CF for three of them. This analysis included 547 non-institutionalized subjects over 60 years old from the northwest of Mexico who were physically independent and without cognitive impairment: 192 subjects were measured using DXA Hologic, while 355 were measured by DXA Lunar. The agreement between each of the equations and DXA was tested considering the DXA model used as a reference method for the design of each equation, using the Bland and Altman procedure, a paired t test, and simple linear regression as objective tests. This process was supported by the differences reported in the literature and confirmed in a subsample of 70 subjects measured with both models. Only six published BIA equations were included. The results showed that four equations overestimated ASM_DXA, and two underestimated it (p < 0.001, 95% CI for Kim's equation:−5.86-−5.45, Toselli's:−0.51-−0.15, Kyle's: 1.43–1.84, Rangel-Peniche's: 0.32–0.74, Sergi's: 0.83–1.23, and Yoshida's: 4.16–4.63 kg). However, Toselli's, Kyle's and Rangel-Peniche's equations were the only ones that complied with having a homogeneous bias. This finding allowed the derivation of CFs, which consisted of subtracting or adding the mean of the differences from the original equation. After estimating ASM applying the respective CF, the new ASM estimations showed no significant bias and its distribution remained homogeneously distributed. Therefore, agreement with DXA in the sample of non-Caucasian was achieved. Adding valid CFs to some BIA equations allowed to reduce the bias of some equations, making them valid to estimate the mean values of ASM at group level.