High body fatness, but not low fat-free mass, predicts disability in older men and women: the Cardiovascular Health Study

Mitochondrial fatty acid beta-oxidation: a possible therapeutic target for skeletal muscle lipotoxicity in peripheral artery disease myopathy

Peripheral artery disease (PAD) is an atherosclerotic disease impacting over 200 million individuals and the prevalence increases with age. PAD occurs when plaque builds up within the peripheral arteries, leading to reduced blood flow and oxygen supply to the outer extremities. Individuals who experience PAD suffer from ischemia, which is typically accompanied by significant damage to skeletal muscles. Additionally, this tissue damage affects mitochondria, causing them to become dysregulated and dysfunctional, resulting in decreased metabolic rates. As there is no known cure for PAD, researchers are exploring potential therapeutic targets by examining coexisting cardiovascular conditions and metabolic risk factors, such as the aging process. Among these comorbidities, type-two diabetes mellitus and obesity are particularly common in PAD cases. These conditions, along with aging itself, are associated with an elevated accumulation of ectopic lipids within skeletal muscles, similar to what is observed in PAD. Researchers have attempted to reduce excess lipid accumulation by increasing the rate of fatty acid beta oxidation. Manipulating acetyl coenzyme A carboxylase 2, a key regulatory protein of fatty acid beta oxidation, has been the primary focus of such research. When acetyl coenzyme A carboxylase 2 is inhibited, it interrupts the conversion of acetyl-CoA into malonyl-CoA, resulting in an increase in the rate of fatty acid beta oxidation. By utilizing samples from PAD patients and applying the pharmacological strategies developed for acetyl coenzyme A carboxylase 2 in diabetes and obesity to PAD, a potential new therapeutic avenue may emerge, offering hope for improved quality of life for individuals suffering from PAD.

Are sit-to-stand and isometric handgrip tests comparable assessment tools to identify dynapenia in sarcopenic people?

Sarcopenia is a neuromuscular disease characterized by the simultaneous existence of reduced muscle strength and muscle atrophy. The current recommendations for the diagnosis of sarcopenia suggest dynapenia be operationalized using either isometric handgrip strength (IHG) or sit-to-stand (STS) tests. However, specific associations between each of these assessment tools and sarcopenia-related parameters have been observed. In addition, important neuromuscular and biomechanical aspects differ between IHG and STS. This scenario has important clinical implications and calls for detailed studies to refine the current recommendations for sarcopenia identification. The present communication presents evidence to foster a constructive debate on the matter.

Accuracy of Resting Energy Expenditure Estimation Equations in Polio Survivors

OBJECTIVE

To evaluate the accuracy of 4 equations validated for the general population to determine resting energy expenditure (REE) in polio survivors.

DESIGN

A descriptive, ambispective, single-center observational cohort study of minimal risk care.

SETTING

Tertiary university care hospital.

PARTICIPANTS

DATAPOL database of polio survivors followed up in a specialist department (N=298).

INTERVENTIONS

None.

MAIN OUTCOMES MEASURES

REE measurement by indirect calorimetry and estimated REE using 4 equations and comparing the values with indirect calorimetry. Analysis of correlations between measured REE and weight, height, and body mass index (BMI) and indicators of severity of polio sequelae.

RESULTS

Of the 298 polio cases in the database between January 2014 and May 2017, 41 were included (19 men and 22 women). Mean±SD BMI was 26.0±5.6 kg/m² (56.1% below 25). Measured REE correlated significantly and positively with weight and weaker with BMI. Correlations between measured and estimated REE were strong (between 0.49 and 0.59); correlations were strongest for the simplified World Health Organization and the Harris and Benedict equations. However, the equations systematically overestimated REE by more than 20%, especially in men. We calculated a correction factor for the World Health Organization scale: -340.3 kcal/d for women and -618.8 kcal/d for men.

CONCLUSION

Analysis of REE is important for polio survivors; The use of estimation equations could lead to the prescription of a nonadapted diet. We determined a correction factor that should be validated in prospective studies.

Age-related low skeletal muscle mass correlates with joint space narrowing in knee osteoarthritis in a South Korean population: a cross-sectional, case-control study

Background

This study was conducted to analyze the effects of low skeletal muscle mass index (SMI) and obesity on aging-related osteoarthritis (OA) in the Korean population.

Methods

A total of 16,601 participants who underwent a dual-energy X-ray absorptiometry and 3,976 subjects with knee X-rays according to the modified Kellgren-Lawrence (KL) system were enrolled. Knees of ≥KL grade 2 were classified as radiologic OA. The severity of joint space narrowing (JSN) was classified by X-rays as normal, mild-to-moderate, and severe JSN in radiologic OA. The subjects were grouped as normal SMI (SMI of ≥–1 standard deviation [SD] of the mean), low SMI class I (SMI of ≥–2 SDs and <–1 SD), and low SMI class II (SMI of <–2 SDs). Obesity was defined as a body mass index (BMI) of ≥27.5 kg/m².

Results

The modified KL grade and JSN severity were negatively correlated with the SMI and positively correlated with BMI and age. The SMI was negatively correlated with age. JSN severity was significantly associated with a low SMI class compared to a normal SMI, which was more prominent in low SMI class II than class I. Obesity was significantly associated with more severe JSN, only for obesity with a low SMI class. Furthermore, patients with a low SMI class, regardless of obesity, were prone to having more severe JSN.

Conclusion

This study suggested that a low SMI class was associated with aging and that an age-related low SMI was more critically related to the severity of JSN in OA.

Sex-different changes of body composition in aging: a systemic review

OBJECTIVE

Aging causes changes in body composition, in which differences in the distribution and amount of fat and muscle tissue affect the development of various diseases according to sex. We conducted a systemic review of the literature and examined the relationship between body composition differences and related health conditions or diseases in older men and women.

METHODS

Three different electronic databases (MEDLINE, Web of Science, and Embase) were used to find articles from 2000 until March 2022. Information on the study design characteristics, setting, measure of body composition, and health outcomes was extracted.

RESULTS

A total of 217 articles were retrieved, and 28 studies met the inclusion criteria. The included studies showed that older men have larger skeletal muscle mass (sMM) than women, while older women have larger fat mass (FM) than men. sMM has a favorable effect on physical performance, bone density, metabolism, cognitive function, and mortality in both men and women; however, the effects of sMM in women are less significant and even negligible compared to those in men. FM is significantly unfavorable for physical performance in women but sometimes favorable or unfavorable for glucose level and cognitive and lung function according to location. FM in men is usually less important for function, bone density, glucose level, and cognitive function than in women.

CONCLUSION

Changes in muscle and fat distribution according to aging and their correlation with health outcomes differ according to sex. Muscle mass may not always be favorable, and fat mass may not always be unfavorable in older adults.

Relationship Between Age-Related Changes in Skeletal Muscle Mass and Physical Function: A Cross-Sectional Study of an Elderly Japanese Population

Skeletal muscle mass and muscle strength are positively correlated, but the relationship between grip strength and global muscle strength is controversial. This study aimed to clarify the changes in site-specific skeletal muscle mass by age group and determine the relationship between site-specific, age-related changes in skeletal muscle mass and physical function in community-dwelling elderly people in Japan. The participants were divided into age groups of five-year intervals (65-69 years, 70-74 years, 75-79 years, and ≥80 years) and were also categorized by sex. The skeletal muscle mass of the upper limbs, lower limbs, and trunk was measured using multifrequency bioelectrical impedance analyzers (InBody 430 (Biospace Co., Ltd., Seoul, Korea) and InBody 470 (InBody Japan Inc., Tokyo, Japan)). For physical function assessment, we measured grip strength, quadriceps strength, sit-up count, sit-and-reach distance, and standing time on one leg with eyes open and performed the timed up and go (TUG) test. The results showed that skeletal muscle mass decreased with age regardless of sex at all measured sites. Furthermore, a partial correlation analysis adjusted for age, physical constitution, and the presence/absence of exercise habits revealed that the highest correlation was between skeletal muscle mass in all sites and grip strength. Thus, monitoring grip strength may be used as a representative of systemic skeletal mass even in Japanese people.

Sex-Specific Associations Between Bone-Loading Score and Adiposity Markers in Middle-Aged and Older Adults

The authors examined sex-specific relationships between fat mass index (FMI), android/gynoid (A/G) fat ratio, relative skeletal muscle mass index, and Bone-Specific Physical Activity Questionnaire derived bone-loading scores (BLSs) in middle-aged and older adults (men, n = 27; women, n = 33; age = 55-75 years). The FMI, A/G fat ratio, and relative skeletal muscle mass index were estimated by dual-energy X-ray absorptiometry. The Bone-Specific Physical Activity Questionnaire was used to assess: (a) BLSpast (age 1 until 12 months before the study visit), (b) BLScurrent (last 12 months), and (c) BLStotal (average of [a] and [b]) scores. Separate multiple linear regression analysis of (a) age, FMI, and relative skeletal muscle mass index and (b) age, height, and A/G fat ratio versus BLS revealed that FMI and A/G fat ratio were negatively associated with BLSpast and BLStotal (p < .05) in women only. Adiposity and, specifically, central adiposity is negatively related to bone-loading physical activity in middle-aged and older women.

Factors Associated with Frailty According to Gender of Older Adults Living Alone

This study was conducted to identify the factors associated with frailty according to gender of older adults living alone in Korea. Data from the National Survey of the Living Conditions of Korean Elderly in 2017 were used. Participants were 2340 older adults who live alone. Frailty was determined based on the frailty criteria developed by van Kan et al. that consist of fatigue, resistance, ambulation, and illness. The collected data were analyzed using descriptive statistics, chi-squared test, t-test, Jonckheere–Terpstra test and multinomial logistic regression. Among the older men living alone, 47.7% were in the pre-frail and 5.1% were in the frail. On the other hand, 51.8% were in the pre-frail and 12.2% were in the frail among the older women living alone. The factors associated with frailty according to gender are as follows. In males, depressive symptoms, limitation in IADL, and number of medications in pre-frail; BMI, limitation in IADL, and number of chronic diseases in frail. In females, depressive symptoms, number of chronic diseases, age, and nutritional status in pre-frail; limitation in IADL, depressive symptoms, age, number of chronic diseases, number of medications, nutritional status in frail. Based on the findings of this study, it is considered necessary to approach frailty management considering gender as well as the classification of frailty.

Body composition by computed tomography vs. dual energy x-ray absorptiometry: Long-term prediction of all-cause mortality in the Health ABC cohort

BACKGROUND

Body composition assessment by computed tomography (CT) predicts health outcomes in diverse populations. However, its performance in predicting mortality has not been directly compared to dual-energy-X-ray-absorptiometry (DXA). Additionally, the association between different body compartments and mortality, acknowledging the compositional nature of human body, is not well-studied. Compositional Data Analysis, that is applied to multivariate proportion-type dataset, may help to account for the inter-relationships of body compartments by constructing log-ratios of components. Here, we determined the associations of baseline CT-based measures of mid-thigh cross-sectional areas vs. DXA measures of body composition with all-cause mortality in Health ABC cohort, using both traditional (individual body compartments) and Compositional Data Analysis (using ratios of body compartments) approaches.

METHODS

The Health ABC study assessed body composition in 2911 older adults in 1996-97. We investigated the individual and ratios of (by Compositional Analysis) body compartments assessed by DXA (lean, fat, and bone-mass) and CT (muscle, subcutaneous fat area, intermuscular fat (IMF), and bone) on mortality, using Cox proportional hazard models.

RESULTS

Lower baseline muscle area by CT (HRmen=0.56 [95%CI: 0.48-0.67], HRwomen=0.60 [0.48-0.74]), fat-mass by DXA (HRmen=0.48 [0.24-0.95]) were predictors of mortality in traditional Cox-regression analysis. Consistently, Compositional Data Analysis revealed that lower muscle area vs. IMF, muscle area vs. bone area, and lower fat-mass vs. lean-mass were associated with higher mortality in both sexes.

CONCLUSION

Both CT measure of muscle area and DXA fat-mass (either individually or relative to other body compartments) were strong predictors of mortality in both sexes in a community research setting.

Prevalence and Effect of Obesity on Mobility According to Different Criteria in Polio Survivors

OBJECTIVE

Obesity is a major and functionally important problem in polio survivors. The aim of this study was to investigate the prevalence of obesity using body mass index and percentage body fat in polio survivors and to analyze the relationship between obesity and mobility.

DESIGN

Eighty-four polio survivors were included. Anthropometric parameters, knee extensor strength, and the Short Physical Performance Battery were evaluated. A questionnaire was used to explore the late effects of poliomyelitis. Obesity was determined using both body mass index and percentage body fat.

RESULTS

The prevalence of obesity in polio survivors was 39.3% and 81.5% using the body mass index and percentage body fat criteria, respectively. The Short Physical Performance Battery scores were significantly different between the obese and nonobese groups as determined by percentage body fat (P < 0.05). Only percentage body fat was significantly associated with mobility after controlling for the confounding variables in obese polio survivors (P < 0.05).

CONCLUSIONS

Obesity in polio survivors was underestimated when the body mass index criteria were used. Percentage body fat was a significantly associated factor for mobility in obese polio survivors. Obesity determined by percentage body fat criteria is useful to address obesity-related problems in polio survivors.

The Association between 25-Hydroxyvitamin D Concentration and Disability Trajectories in Very Old Adults: The Newcastle 85+ Study

Background: Low vitamin D status is common in very old adults which may have adverse consequences for muscle function, a major predictor of disability. Aims: To explore the association between 25-hydroxyvitamin D [25(OH)D] concentrations and disability trajectories in very old adults and to determine whether there is an 'adequate' 25(OH)D concentration which might protect against a faster disability trajectory. Methodology: A total of 775 participants from the Newcastle 85+ Study for who 25(OH)D concentration at baseline was available. Serum 25(OH)D concentrations of <25 nmol/L, 25-50 nmol/L and >50 nmol/L were used as cut-offs to define low, moderate and high vitamin D status, respectively. Disability was defined as difficulty in performing 17 activities of daily living, at baseline, after 18, 36 and 60 months. Results: A three-trajectory model was derived (low-to-mild, mild-to-moderate and moderate-to-severe). In partially adjusted models, participants with 25(OH)D concentrations <25 nmol/L were more likely to have moderate and severe disability trajectories, even after adjusting for sex, living in an institution, season, cognitive status, BMI and vitamin D supplement use. However, this association disappeared after further adjustment for physical activity. Conclusions: Vitamin D status does not appear to influence the trajectories of disability in very old adults.

Association of Sex or Race With the Effect of Weight Loss on Physical Function: A Secondary Analysis of 8 Randomized Clinical Trials

IMPORTANCE

Consideration of differential treatment effects among subgroups in clinical trial research is a topic of increasing interest. This is an especially salient issue for weight loss trials.

OBJECTIVE

To determine whether stratification by sex and race is associated with meaningful differences in physical function response to weight loss among older adults.

DESIGN, SETTING, AND PARTICIPANTS

This pooled analysis used individual-level data from 8 completed randomized clinical trials of weight loss conducted at Wake Forest University or Wake Forest School of Medicine, Winston-Salem, North Carolina. Data were housed within the Wake Forest Older Americans Independence Center data repository and provided complete exposure, outcome, and covariate information. Data were collected from November 1996 to March 30, 2017, and analyzed from August 15, 2019, to June 10, 2020.

EXPOSURES

Treatment arms within each study were collapsed into caloric restriction (CR [n = 734]) and non-CR (n = 583) categories based on whether caloric restriction was specified in the original study protocol.

MAIN OUTCOMES AND MEASURES

Objectively measured 6-month change in weight, fast-paced gait speed (meters per second), and Short Physical Performance Battery (SPPB) score.

RESULTS

A total of 1317 adults (mean [SD] age, 67.7 [5.4] years; 920 [69.9%] female; 275 [20.9%] Black) with overweight or obesity (mean [SD] body mass index [calculated as weight in kilograms divided by height in meters squared], 33.9 [4.4]) were included at baseline. Six-month weight change achieved among those randomized to CR was -7.7% (95% CI, -8.3% to -7.2%), with no difference noted by sex; however, White individuals lost more weight than Black individuals assigned to CR (-9.0% [95% CI, -9.6% to -8.4%] vs -6.0% [95% CI, -6.9% to 5.2%]; P < .001), and all CR groups lost a significantly greater amount from baseline compared with non-CR groups (Black participants in CR vs non-CR groups, -5.3% [95% CI, -6.4% to -4.1%; P < .001]; White participants in CR vs non-CR groups, -7.2% [95% CI, -7.8% to -6.6%; P < .001]). Women experienced greater weight loss-associated improvement in SPPB score (CR group, 0.35 [95% CI, 0.18-0.52]; non-CR group, 0.08 [95% CI, -0.11 to 0.27]) compared with men (CR group, 0.23 [95% CI, 0.00-0.46]; non-CR group, 0.34 [95% CI, 0.09-0.58]; P = .03). Black participants experienced greater weight loss-associated improvement in gait speed (CR group, 0.08 [95% CI, 0.05-0.10] m/s; non-CR group, 0.02 [95% CI, -0.01 to 0.05] m/s) compared with White participants (CR group, 0.07 [95% CI, 0.06-0.09] m/s; non-CR group, 0.06 [95% CI, 0.04-0.08] m/s; P = .02).

CONCLUSIONS AND RELEVANCE

The association of weight loss on physical function in older adults appears to differ by sex and race. These findings affirm the need to consider biological variables in clinical trial design.

Long-term rates of change in musculoskeletal aging and body composition: findings from the Health, Aging and Body Composition Study

Musculoskeletal disorders are common among older people. Preventive strategies require understanding of age-related changes in strength, function and body composition, including how they interrelate. We have described, and examined associations between, 9-year changes in these parameters among 2917 Health, Aging and Body Composition Study participants (aged 70-79 years). Appendicular lean mass (ALM), whole body fat mass and total hip BMD were ascertained using DXA; muscle strength by grip dynamometry; and muscle function by gait speed. For each characteristic annualised percentage changes were calculated; measures of conditional change (independent of baseline) were derived and their interrelationships were examined using Pearson correlations; proportion of variance at 9-year follow-up explained by baseline level was estimated; and mean trajectories in relation to age were estimated using linear mixed models. Analyses were stratified by sex. Median [lower quartile, upper quartile] annual percentage declines were grip strength (1.5 [0.0, 2.9]), gait speed (2.0 [0.6, 3.7]), ALM (0.7 [0.1, 1.4]), fat mass (0.4 [- 1.1, 1.9]) and hip BMD (0.5 [0.0, 1.1]). Declines were linear for ALM and accelerated over time for other characteristics. Most conditional change measures were positively correlated, most strongly between ALM, fat mass and hip BMD (r > 0.28). Proportion of variation at follow-up explained by baseline was lower for grip strength and gait speed (39-52%) than other characteristics (69-86%). Strength and function declined more rapidly, and were less correlated between baseline and follow-up, than measures of body composition. Therefore, broader intervention strategies to prevent loss of strength and function in later life are required as those targeting body composition alone may be insufficient.

Effects of comorbid physical frailty and low muscle mass on incident disability in community-dwelling older adults: A 24-month follow-up longitudinal study

OBJECTIVES

Low muscle mass frequently precedes or coexists with physical frailty in late life. This study aimed to examine whether comorbid physical frailty and low muscle mass increase the risk of incident disability in community-dwelling older adults.

STUDY DESIGN

A prospective cohort study.

METHODS

Participants were 9229 community-dwelling older Japanese adults (≥65 years). Longitudinal data on incident disability were collected for up to a maximum of 24 months from baseline. Physical frailty was defined as experiencing three or more of the following five symptoms: slowness, weakness, exhaustion, low activity, and weight loss. Low muscle mass was identified based on the AWGS definition (<7.0 kg/m² for men and <5.7 kg/m² for women).

RESULTS

During the follow-up period, 460 (5.0%) individuals had incident disability. The prevalence rates of low muscle mass, physical frailty, and comorbid physical frailty and low muscle mass were 12.0% (n = 1104), 6.8 % (n = 624), and 1.8 % (n = 167), respectively. Compared with non-physical frailty/normal muscle mass, physical frailty (hazard ratio (HR) 2.50, 95% confidential interval (CI) 1.97-3.18) and comorbid physical frailty and low muscle mass (HR 4.03, 95% CI 2.85-5.70) were significantly associated with incident disability after adjusting for the covariates.

CONCLUSIONS

Although low muscle mass alone may not be associated with an increased risk of incident disability in community-dwelling older adults, comorbid physical frailty and low muscle mass had a significant impact on disability. Low muscle mass was a risk factor for disability in older adults with physical frailty.

Gait speed and body mass index: Results from the AMI study

BACKGROUND

While physical frailty and malnutrition/obesity (parameters easily measured by a nurse) are not the same, older persons who are malnourished/obese are more likely to be frail and there is a potential overlap between these conditions. The objective was to examine the relationship between gait speed (GS) and body mass index (BMI) in men and women aged 75 years and older.

DESIGN

Cross-sectional analysis.

SETTING, PARTICIPANTS

Data from the Aging Multidisciplinary Investigation (AMI), a French prospective cohort study with participants randomly selected from the farmer Health Insurance rolls.

MEASUREMENTS

Usual GS was measured over a 4 meters-track. BMI was categorized using clinical cut-points for European populations: (e.g, <20.0 kg/m2; 20.0-24.9 kg/m2; 25.0-29.9 kg/m2; 30.0-34.9 kg/m2; ≥35.0 kg/m2).

RESULTS

The current analyses were performed in 449 participants. Mean age was 81 years. Being malnourished/obese was significantly associated with slow GS. Unadjusted and age-adjusted models showed that underweight, overweight and obesity statuses were significantly associated with slow GS for both women (0.83m/s [0.61; 1.04], 0.87m/s [0.72; 1.02], 0.70 m/s [0.41; 0.98], respectively) and men (0.83m/s [0.61; 1.04], 1.11m/s [1.03; 1.20], 0.97m/s [0.75; 1.19], respectively).

CONCLUSION

Malnourished/obese are associated with slow GS in older persons. These variables could be contributed at comprehensively and complementarily assessing the older person.

Changes in knee extension peak torque and body composition and their relationship with change in gait speed

BACKGROUND

Slow gait speed is a powerful predictor of disability in activities of daily living and mortality. Muscle strength and body composition change over time, but their changes differ by sex. How these parameters jointly affect gait speed decline is unknown. Understanding this association could help develop and evaluate the sex-specific effects of lifestyle interventions to delay gait speed decline in older adults. We assessed whether changes in strength (Δstrength), appendicular lean mass (ΔALM), and fat mass (Δfat) jointly relate to change in gait speed and whether the association differs by sex.

METHODS

The analytic sample comprised 575 women and 539 men aged 22-95 years enrolled in the Baltimore Longitudinal Study of Aging. Mean follow-up was 4.0 years. Measures included isometric knee extension strength, dual-energy X-ray absorptiometry-assessed ALM and fat mass, and gait speed from the 400 m fast pace walk. Sex-specific linear mixed models were adjusted for follow-up time and baseline age, race, height, ALM, fat mass, peak torque, and gait speed. We also included second-order interaction terms of the key predictive variables (e.g. Δstrength × ΔALM). To interpret the interactions, we estimated average gait declines using the 25th or 75th percentile of the two significant predictive variables and then assessed which condition relates to larger decline in gait speed.

RESULTS

In both sexes, independent of ΔALM and Δfat, larger decline in strength significantly related to larger decline in gait speed (P = 0.01 for both sexes). In men, interactions between Δstrength × ΔALM and Δfat by ΔALM were associated with change in gait speed; men with greater declines in both muscle strength and ALM or greater declines in both ALM and fat have steeper gait speed decline. In contrast, in women, the interaction between Δfat and ΔALM was associated with change in gait speed; women with an increase in fat mass combined with less decline in ALM have steeper gait speed decline.

CONCLUSIONS

While change in strength affects change in gait speed in both sexes, the effects of body composition change differ by sex. Dual-energy X-ray absorptiometry-based estimates of lean mass may be confounded by intramuscular fat. Future studies should examine sex-specific combined effects of change in strength and body composition on mobility using multiple techniques to measure body composition. Intervention studies should consider testing sex-specific interventions on body composition.

Lipotoxicity, aging, and muscle contractility: does fiber type matter?

Sarcopenia is a universal characteristic of the aging process and is often accompanied by increases in whole-body adiposity. These changes in body composition have important clinical implications, given that loss of muscle and gain of fat mass are both significantly and independently associated with declining physical performance as well as an increased risk for disability, hospitalizations, and mortality in older individuals. This increased fat mass is not exclusively stored in adipose depots but may become deposited in non-adipose tissues, such as skeletal muscle, when the oxidative capacity of the adipose tissue itself is exceeded. The redistributed adipose tissue is thought to exert detrimental local effects on the muscle environment given the close proximity. Thus, sarcopenia observed with aging may be better defined in the context of loss of muscle quality rather than loss of muscle quantity per se. In this perspective, we briefly review the age-related physiological changes in cellularity, secretory profiles, and inflammatory status of adipose tissue which drive lipotoxicity (spillover) of skeletal muscle and then provide evidence of how this may affect specific fiber type contractility. We focus on biological contributors (cellular machinery) to contractility for which there is some evidence of vulnerability to lipid stress distinguishing between fiber types.

Strong Relation Between Muscle Mass Determined by D3-creatine Dilution, Physical Performance, and Incidence of Falls and Mobility Limitations in a Prospective Cohort of Older Men

BACKGROUND

Direct assessment of skeletal muscle mass in older adults is clinically challenging. Relationships between lean mass and late-life outcomes have been inconsistent. The D3-creatine dilution method provides a direct assessment of muscle mass.

METHODS

Muscle mass was assessed by D3-creatine (D3Cr) dilution in 1,382 men (mean age, 84.2 years). Participants completed the Short Physical Performance Battery (SPPB); usual walking speed (6 m); and dual x-ray absorptiometry (DXA) lean mass. Men self-reported mobility limitations (difficulty walking 2-3 blocks or climbing 10 steps); recurrent falls (2+); and serious injurious falls in the subsequent year. Across quartiles of D3Cr muscle mass/body mass, multivariate linear models calculated means for SPPB and gait speed; multivariate logistic models calculated odds ratios for incident mobility limitations or falls.

RESULTS

Compared to men in the highest quartile, those in the lowest quartile of D3Cr muscle mass/body mass had slower gait speed (Q1: 1.04 vs Q4: 1.17 m/s); lower SPPB (Q1: 8.4 vs Q4: 10.4 points); greater likelihood of incident serious injurious falls (odds ratio [OR] Q1 vs Q4: 2.49, 95% confidence interval [CI]: 1.37, 4.54); prevalent mobility limitation (OR Q1 vs Q4,: 6.1, 95% CI: 3.7, 10.3) and incident mobility limitation (OR Q1 vs Q4: 2.15 95% CI: 1.42, 3.26); p for trend < .001 for all. Results for incident recurrent falls were in the similar direction (p = .156). DXA lean mass had weaker associations with the outcomes.

CONCLUSIONS

Unlike DXA lean mass, low D3Cr muscle mass/body mass is strongly related to physical performance, mobility, and incident injurious falls in older men.

'Just because I'm old it doesn't mean I have to be fat': a qualitative study exploring older adults' views and experiences of weight management

OBJECTIVES

The aim of this study was to explore older adults' beliefs about the appropriateness of weight management, and how their experiences and expectations of weight management have changed as they have got older.

DESIGN

Qualitative semistructured interview study.

SETTING

UK.

PARTICIPANTS

Older adults (≥65 years) in the UK who had recent (<5 years) experience of trying to manage their weight (n=15; 12 women; 73% white British).

RESULTS

Data were analysed using thematic analysis. Emergent themes highlighted that weight remained a concern for many older adults, although having a high body weight was seen to be more acceptable at older than younger ages. Excess weight was reported to have negative consequences for health and well-being which participants felt could be alleviated by losing weight. Participants were motivated to lose weight for appearance and health reasons, but mentioned finding it harder to lose weight as they had got older and generally felt they had received limited guidance on weight management from health professionals.

CONCLUSIONS

The views of our participants highlight the need for further research into safe and effective methods of weight loss for older people and indicate that advice and support from health professionals would be welcomed.

Body Composition Remodeling and Incident Mobility Limitations in African Ancestry Men

BACKGROUND

Mobility limitations are common, with higher prevalence in African Americans compared with whites, and are associated with disability, institutionalization, and death. Aging is associated with losses of lean mass and a shift to central adiposity, which are more pronounced in African Americans. We aimed to examine the association of body composition remodeling with incident mobility limitations in older men of African ancestry.

METHODS

Seven-year changes in body composition were measured using peripheral quantitative computed tomography (pQCT) of the calf and whole-body dual x-ray absorptiometry (DXA) in 505 African ancestry men aged ≥60 years and free of self-reported mobility limitations at baseline. Self-reported incident mobility limitations were assessed at 7-year follow-up. Odds of developing mobility limitations associated with baseline and change in body composition were quantified using separate logistic regression models.

RESULTS

Seventy-five men (14.9%) developed incident mobility limitations over 6.2 ± 0.6 years. Baseline body composition was not associated with incident mobility limitations. After adjustment for covariates, gaining total and intermuscular fat were associated with incident mobility limitations (odds ratio [OR]: 1.60; 95% confidence interval [CI]: 1.21-2.13; OR: 1.51; 95% CI: 1.18-1.94). Changes in DXA lean mass were not related to mobility limitations; however, maintaining pQCT calf muscle area was protective against mobility limitations (OR: 0.65; 95% CI: 0.48-0.87).

CONCLUSIONS

Increases in body fat, and particularly intermuscular fat, and decreases in calf skeletal muscle area were associated with a higher risk of developing mobility limitations. Our findings emphasize the importance of body composition remodeling in the development of mobility limitations among African ancestry men.

Aging and Imaging Assessment of Body Composition: From Fat to Facts

The aging process is characterized by the chronic inflammatory status called "inflammaging", which shares major molecular and cellular features with the metabolism-induced inflammation called "metaflammation." Metaflammation is mainly driven by overnutrition and nutrient excess, but other contributing factors are metabolic modifications related to the specific body composition (BC) changes occurring with age. The aging process is indeed characterized by an increase in body total fat mass and a concomitant decrease in lean mass and bone density, that are independent from general and physiological fluctuations in weight and body mass index (BMI). Body adiposity is also re-distributed with age, resulting in a general increase in trunk fat (mainly abdominal fat) and a reduction in appendicular fat (mainly subcutaneous fat). Moreover, the accumulation of fat infiltration in organs such as liver and muscles also increases in elderly, while subcutaneous fat mass tends to decrease. These specific variations in BC are considered risk factors for the major age-related diseases, such as cardiovascular diseases, type 2 diabetes, sarcopenia and osteoporosis, and can predispose to disabilities. Thus, the maintenance of a balance rate of fat, muscle and bone is crucial to preserve metabolic homeostasis and a health status, positively contributing to a successful aging. For this reason, a detailed assessment of BC in elderly is critical and could be an additional preventive personalized strategy for age-related diseases. Despite BMI and other clinical measures, such as waist circumference measurement, waist-hip ratio, underwater weighing and bioelectrical impedance, are widely used as a surrogate measure for body adiposity, they barely reflect the distribution of body fat. Because of the great advantages offered by imaging tools in research and clinics, the attention of clinicians is now moving to powerful imaging techniques such as computed tomography, magnetic resonance imaging, dual-energy X-ray absorptiometry and ultrasound to obtain a more accurate estimation of BC. The aim of this review is to present the state of the art of the imaging techniques that are currently available to measure BC and that can be applied to the study of BC changes in the elderly, outlining advantages and disadvantages of each technique.

Effect of Protein Supplementation Combined with Resistance Training on Muscle Mass, Strength and Function in the Elderly: A Systematic Review and Meta-Analysis

BACKGROUND

The loss of muscle mass, strength and function associated with increasing age has various health ramifications, including the elevated risk for falls, fractures, frailty, poor quality of life, and mortality. Several studies have confirmed the effects of protein supplementation and RT (resistance training) for this age-related change independently, but whether a combination of the two produces a stronger effect remains controversial.

OBJECTIVE

This study aims to explore whether a combination of protein supplementation and RT leads to reduction of muscle mass, strength and function in the elderly.

METHODS

We retrieved RCTs (randomized controlled trials) reporting the effects of protein supplementation combined with RT on muscle mass, strength and function in the elderly, published before May 2018 through PubMed, MEDLINE, Embase, and manual searches.

RESULTS

Twenty-one RCTs were included, involving 1,249 participants. The results showed that protein supplementation combine with RT significantly enhances the muscle mass and strength of the older adults, where FFM (fat-free mass) increased by 0.23 kg (95% CI: 0.09, 0.38; P=0.002), ASMM (appendicular skeletal muscle mass) by 0.39 kg (95% CI: 0.14, 0.64; P=0.002), handgrip strength by 0.29 kg (95% CI: 0.08, 0.50; P=0.008), knee extension strength by 0.27 kg (95% CI: 0.06, 0.47; P=0.013), leg press strength by 0.33 kg (95% CI: 0.01, 0.64; P=0.04), but no significant effects were seen on muscle function.

CONCLUSION

Compared to simple RT, protein supplementation combine with RT is more effective in enhancing the muscle mass and strength in the elderly, and the findings do not support the benefit of combination treatment for muscle function.

Are changes in body-mass-index associated with changes in depressive symptoms? Findings of a population-based longitudinal study among older Germans

BACKGROUND

The longitudinal relationship between BMI and depressive symptoms is not well understood. Therefore, we aimed at investigating the long-term association between body-mass-index (BMI) and depressive symptoms among older Germans.

METHODS

Data were derived from a population-based longitudinal study of adults aged 40 and above in Germany (German Ageing Survey, DEAS). Four waves (2002-2014) were used. Depressive symptoms was assessed by the Center for Epidemiologic Studies Depression Scale (CES-D). Linear, quadratic and cubic terms were included for self-reported BMI. Fixed effects regressions were used to estimate the predictors of depressive symptoms.

RESULTS

FE regressions showed a curvilinear effect of BMI on depressive symptoms in the total sample and in women, but not men, with significant gender differences. In sum, the greater the extreme of BMI (either higher or lower), the greater the risk for depressive symptoms in the total sample and in women.

CONCLUSION

Our findings indicate that the effect of BMI on depressive symptoms is by no means simple. The current study highlight the importance of comprehensive treatment of depression, which include management of (extreme) weight to manage depressive symptoms.

The fat mass index, not the fat-free mass index, is associated with impaired physical performance in older adult subjects: Evidence from a cross-sectional study

BACKGROUND

Impaired physical performance (IPP) and physical disability (PD) are two serious public health problems in older adult populations worldwide. While studies show that changes in body composition are important risk factors for developing these conditions, there is little evidence that the fat-free mass (FFM) and fat mass (FM) indices (FFMI and FMI, respectively) are associated with IPP in older men and women. This study assessed the association among FFMI, FMI, and IPP using Short Physical Performance Battery (SPPB) in Mexican men and women aged over 60 years.

METHODS

This cross-sectional study included 217 older people (men 34.6%, women 65.4%; 60-92 years). FFM and FM were assessed by dual X-ray absorptiometry, assuming a two-compartment model. FFM and FM were adjusted by height squared and the indices were obtained. After assessment of physical performance by SPPB, subjects with scores ≤6 were classified as having IPP. Associations were tested by multiple logistic regression analysis in separated models.

RESULTS

IPP prevalence was 14.3%. Women were affected more than men. Regression analysis showed no significant association between FFMI and IPP, but FMI was strongly-associated, as for each unit increase in FMI, the risk of IPP rose significantly (OR: 1.14), and this result remained significant after adjusting for age, comorbidity, polypharmacy, and the appendicular skeletal muscle mass index (OR: 1.23; p ≤ 0.001). These results emphasize the importance of preventing increases in FM and avoiding overweight and obesity in older men and women.

Addressing Obesity in Aging Patients

Obesity in older adults affects not only morbidity and mortality but, importantly, quality of life and the risk of institutionalization. Weight loss interventions can effectively lead to improved physical function. Diet-alone interventions can detrimentally affect muscle and bone physiology and, without interventions to affect these elements, can lead to adverse outcomes. Understanding social and nutritional issues facing older adults is of utmost importance to primary care providers. This article will also discuss the insufficient evidence related to pharmacotherapy as well as providing an overview of using physiologic rather than chronologic age for identifying suitable candidates for bariatric surgery.

Age-Related Changes in Fat Mass and Distribution in Men-the Cross-Sectional STRAMBO Study

Data on age-related differences in fat mass and distribution in men are scarce. We performed a cross-sectional analysis of age-related differences in fat distribution in men. In a cohort of 1133 men aged 20-87 yr, body composition was assessed using a Hologic Discovery A device. We assessed fat mass (FM) and FM indices adjusted for height. Interindividual variability was calculated as standard deviation, interquartile range, and difference between the 95th and 5th percentiles in 5-yr age groups. After adjustment for lifestyle factors, the FM and FM index of appendicular, gynoid, central, android, and subcutaneous abdominal compartments increased with age. Their variability did not vary with age. Visceral FM was 181% higher in men aged >80 yr compared to men aged 20-30 yr, and the variability increased with age. FM in the central, android, subcutaneous abdominal, and visceral compartments correlated with age significantly more strongly before the age of 70 than after this age. The relative differences between the elderly and younger men were greater for visceral FM than for subcutaneous (abdominal and appendicular) fat. The interindividual variability in visceral FM is higher in elderly men. The association between visceral FM and age is stronger before the age of 70.

Assessment of muscle mass relative to fat mass and associations with physical functioning in rheumatoid arthritis

Objectives

To determine whether a novel measure of appendicular lean mass relative to fat mass is associated with physical functioning in RA.

Methods

In a cross-sectional design, three independent RA cohorts were retrospectively analysed. Whole-body DXA measures of appendicular lean mass index (ALMI, kg/m 2 ) and fat mass index (FMI, kg/m 2 ) were converted to age, sex and race-specific Z-scores using published National Health and Nutrition Examination Survey reference ranges. Adiposity-adjusted ALMI Z-scores (ALMI FMI ) were determined using a published method to adjust for normal associations between ALMI and FMI Z-scores. Associations between ALMI Z-scores, ALMI FMI Z-scores and physical functioning were assessed after adjusting for age, sex and study. Functional outcomes assessed included the HAQ, Valued Life Activities assessment and Short Physical Performance Battery. Low lean for age was defined as a Z-score of -1 or less.

Results

Our sample consisted of 442 patients with RA. The combined cohort had a mean ALMI Z-score of - 0.51 (1.08) and a mean ALMI FMI Z-score of - 0.58 (1.53), suggesting muscle mass deficits compared with a nationally representative sample. Greater ALMI FMI Z-scores demonstrated stronger associations with better functional outcomes compared with ALMI Z-scores. Associations were not attenuated with adjustment for systemic inflammation or pain. The FMI Z-score was independently associated with physical functioning, with a stronger association seen among patients with greater FMI Z-score. Adiposity-adjusted definitions of low lean mass more clearly identified those with functional impairment.

Conclusion

Estimates of appendicular lean mass that are adjusted for adiposity demonstrate stronger positive associations with functional outcomes compared with unadjusted estimates.

Obesity as a risk factor for developing functional limitation among older adults: A conditional inference tree analysis

OBJECTIVE

To examine the risk factors of developing functional decline and make probabilistic predictions by using a tree-based method that allows higher order polynomials and interactions of the risk factors.

METHODS

The conditional inference tree analysis, a data mining approach, was used to construct a risk stratification algorithm for developing functional limitation based on BMI and other potential risk factors for disability in 1,951 older adults without functional limitations at baseline (baseline age 73.1 ± 4.2 y). We also analyzed the data with multivariate stepwise logistic regression and compared the two approaches (e.g., cross-validation). Over a mean of 9.2 ± 1.7 years of follow-up, 221 individuals developed functional limitation.

RESULTS

Higher BMI, age, and comorbidity were consistently identified as significant risk factors for functional decline using both methods. Based on these factors, individuals were stratified into four risk groups via the conditional inference tree analysis. Compared to the low-risk group, all other groups had a significantly higher risk of developing functional limitation. The odds ratio comparing two extreme categories was 9.09 (95% confidence interval: 4.68, 17.6).

CONCLUSIONS

Higher BMI, age, and comorbid disease were consistently identified as significant risk factors for functional decline among older individuals across all approaches and analyses.

Strength measures are better than muscle mass measures in predicting health-related outcomes in older people: time to abandon the term sarcopenia?

There is no clear consensus on definition, cut-points or standardised assessments of sarcopenia. We found a lower limb strength assessment was at least as effective in predicting balance, mobility and falls in 419 older people as muscle mass-based measures of sarcopenia.

INTRODUCTION

There is currently no consensus on the definition, cut-points or standardised assessments of sarcopenia. This study aimed to investigate whether several published definitions of sarcopenia differentiate between older people with respect to important functional and health outcomes.

METHODS

Four hundred nineteen community-living older adults (mean age 81.2 ± 4.5, 49 % female) completed assessments of body composition (dual-energy X-ray absorptiometry), strength, balance, mobility and disability. Falls were recorded prospectively for a year using monthly calendars. Sarcopenia was defined according to four skeletal mass-based definitions, two strength-based definitions (handgrip or knee extensor force) and a consensus algorithm (low mass and low strength or slow gait speed). Obesity was defined according to percentage fat mass or waist circumference.

RESULTS

The four skeletal mass-based definitions varied considerably with respect to the percentage of participants classified as sarcopenic and their predictive accuracy for functional and health outcomes. The knee extension strength-based definition was equivalent to or better than the mass-based and consensus algorithm definitions; i.e. weaker participants performed poorly in tests of leaning balance, stepping reaction time, gait speed and mobility. They also had higher physiological fall risk scores and were 43 % more likely to fall at home than their stronger counterparts. Adding obesity to sarcopenia definitions identified participants with greater self-reported disability.

CONCLUSIONS

A simple lower limb strength assessment was at least as effective in predicting balance, functional mobility and falls in older people as more expensive and time-consuming muscle mass-based measures. These findings imply that functional terms such as muscle weakness or motor impairment are preferable to sarcopenia.

Body mass index, falls, and injurious falls among U.S. adults: Findings from the 2014 Behavioral Risk Factor Surveillance System

Falls are an important health concern because they are associated with loss of independence and disability, particularly among women. We determined the age- and sex-specific prevalence of injurious falls among adults in the United States and examined the impact of obesity on fall risk. Self-reported falls, injurious falls, and health histories were obtained from 280,035 adults aged 45-79years in the 2014 Behavioral Risk Factor Surveillance System. Body mass index was categorized as underweight (<18.5kg/m²), normal weight (18.5-24.9kg/m²), overweight 25-29.9kg/m²), class I obesity (30.0-34.9kg/m²), or class II/III obesity (≥35.0kg/m²) based on self-reported height and weight. Data were analyzed using weighted age- and sex-specific prevalence rates and Poisson regression. Overall, 11.0% reported ≥1 injurious fall in the previous 12months. Mid-life women 55-59years reported the highest prevalence of injurious falls (15.4%). Among mid-life women, overweight was associated with injurious falls (RR=1.17; 95% CI: 1.08, 1.28), but overweight was not associated with falling among other age-sex groups. Class II/III obesity was associated with injurious falls among all age-sex groups. After considering the mediators like health conditions (depression, cardiovascular disease, diabetes, arthritis) and behaviors (physical activity, sleep), the association of class II/III obesity and injurious fall risk persisted only among mid-life women (RR=1.23; 95% CI: 1.12, 1.36). Not only are mid-life women at high risk for falls, but the class II/III obesity is a risk factor for injurious falls. Targeting mid-life women for fall and injury prevention is an important aim for practitioners, particularly given unique correlates of falling for this group.

Need for Weight Management among Postmenopausal Early Breast Cancer Patients Receiving Adjuvant Endocrine Therapy

Increasingly effective adjuvant therapies mean that the prognosis for postmenopausal women with breast cancer has never been better. Weight problems are common among breast cancer patients and worsen due to the impact of diagnosis and treatment. Recent studies have linked excess weight with the risk of recurrence of breast cancer among premenopausal women. While general obesity (body mass index) does not appear to influence the already much improved prognosis for postmenopausal women, there is some evidence that limiting central obesity and improving insulin resistance may improve survival. The focus of attention for postmenopausal breast cancer survivors is also shifting to consider the mortality and morbidity from other weight-related cancers and noncancer causes, such as cardiovascular disease, making weight control a potentially important adjunct to endocrine therapy. This paper outlines the rationale and optimal design for effective weight management strategies among postmenopausal breast cancer patients receiving endocrine therapy.

Body size measures, hemostatic and inflammatory markers and risk of venous thrombosis: The Longitudinal Investigation of Thromboembolism Etiology

OBJECTIVE

Obesity is an important venous thrombosis (VT) risk factor but the reasons for this are unclear.

MATERIALS AND METHODS

In a cohort of 20,914 individuals aged 45 and older without prior VT, we calculated the relative risk (RR) of VT over 12.6years follow-up according to baseline body size measures, and studied whether associations were mediated by biomarkers of hemostasis and inflammation that are related to adiposity.

RESULTS

Greater levels of all body size measures (weight, height, waist, hip circumference, calf circumference, body-mass index, waist-hip ratio, fat mass and fat-free mass) were associated with increased risk of VT, with 4th versus 1st quartile RRs of 1.5-3.0. There were no multiplicative interactions of biomarkers with obesity status. Adjustment for biomarkers associated with VT risk and body size (factors VII and VIII, von Willebrand factor, partial thromboplastin time, D-dimer, C-reactive protein and factor XI) only marginally lowered, or did not impact, the RRs associated with body size measures.

CONCLUSIONS

Greater body size, by multiple measures, is a risk factor for VT. Associations were not mediated by circulating levels of studied biomarkers suggesting that body size relates to VT because of physical factors associated with blood flow, not the hypercoagulability or inflammation associated with adiposity.

Sex- and age-specific percentiles of body composition indices for Chinese adults using dual-energy X-ray absorptiometry

Purpose

The aims of the study were to develop sex- and age-specific percentiles for lean mass index (LMI), appendicular LMI (aLMI), fat mass index (FMI), and body fat distribution indices in Chinese adults using dual-energy X-ray absorptiometry (DXA), and to compare those indices with those of other ethnicities using the US NHANES data.

Methods

Whole-body and regional lean mass and fat mass (FM) were measured using DXA in 5688 healthy males (n = 1693) and females (n = 3995) aged 20–90 years. Body fat distribution indices were expressed as % fat trunk/% fat legs, trunk/appendicular FM ratio (FMR), and android/gynoid FMR. Percentile curves of LMI, aLMI, FMI, and body fat distribution indices were obtained by the Lambda–Mu–Sigma method.

Results

The aLMI and LMI were negatively associated with age, decreasing from the fifth decade for males, but were not associated with age in females. Females had more total FM than males, whereas males had greater central adiposity (% fat trunk/% fat legs ratio, trunk/appendicular FMR, and android/gynoid FMR) than females. Moreover, FMI and body fat distribution indices consistently increased with age in both sexes, especially in women. In comparison with white, black, and Mexican populations in the USA, Chinese adults had lower total FM, but had greater central adiposity (% fat trunk/% fat legs ratio and trunk/appendicular FMR). Additionally, older white and Mexican populations showed greater decreases for aLMI and LMI than their Chinese counterparts.

Conclusions

We present the sex- and age-specific percentiles for aLMI, LMI, FMI, and body fat distribution indices by DXA in Chinese adults, which may refine the individual assessment of the nutritional status of Chinese adults.

The Body and the Beautiful: Health, Attractiveness and Body Composition in Men's and Women's Bodies

The dominant evolutionary theory of physical attraction posits that attractiveness reflects physiological health, and attraction is a mechanism for identifying a healthy mate. Previous studies have found that perceptions of the healthiest body mass index (weight scaled for height; BMI) for women are close to healthy BMI guidelines, while the most attractive BMI is significantly lower, possibly pointing to an influence of sociocultural factors in determining attractive BMI. However, less is known about ideal body size for men. Further, research has not addressed the role of body fat and muscle, which have distinct relationships with health and are conflated in BMI, in determining perceived health and attractiveness. Here, we hypothesised that, if attractiveness reflects physiological health, the most attractive and healthy appearing body composition should be in line with physiologically healthy body composition. Thirty female and 33 male observers were instructed to manipulate 15 female and 15 male body images in terms of their fat and muscle to optimise perceived health and, separately, attractiveness. Observers were unaware that they were manipulating the muscle and fat content of bodies. The most attractive apparent fat mass for female bodies was significantly lower than the healthiest appearing fat mass (and was lower than the physiologically healthy range), with no significant difference for muscle mass. The optimal fat and muscle mass for men's bodies was in line with the healthy range. Male observers preferred a significantly lower overall male body mass than did female observers. While the body fat and muscle associated with healthy and attractive appearance is broadly in line with physiologically healthy values, deviations from this pattern suggest that future research should examine a possible role for internalization of body ideals in influencing perceptions of attractive body composition, particularly in women.

High risk of fall, poor physical function, and low grip strength in men with fracture-the STRAMBO study

BACKGROUND

Several studies assessed the association of prevalent fractures with muscle mass, strength, and physical capacity in men. Clinical impact of these associations is not clear, and they could be influenced by confounders. Our aim was to assess the association of the prevalent fractures with muscle strength, physical function, and the risk of subsequent falls in older men after adjustment for muscle mass and potential confounders.

METHODS

In a cohort of 890 men aged 50 and older, we assessed appendicular skeletal muscle mass (ASM) by DXA, grip strength, physical function (chair stands, static, and dynamic balance). Relative ASM (RASM) was calculated as ASM / (height)(2). Then, 813 men aged 60 and over were followed up prospectively for 5 years and 144 sustained >1 incident falls. All the analyses were adjusted for lifestyle factors, co-morbidities, and hormones known to influence muscle and physical function.

RESULTS

Low leisure physical activity, very high occupational physical activity, Parkinson's disease, diabetes mellitus, low apparent free testosterone concentration (AFTC), as well as Grade 2 and 3 vertebral fractures and multiple fractures were associated with lower grip strength when adjusted for confounders including upper limb RASM. Low leisure physical activity, very high occupational physical activity, diabetes mellitus, prior stroke, low AFTC and 25-hydroxycholecalciferol, high C-reactive protein, vertebral fractures, and non-vertebral fractures were associated with poor physical function (lowest quintile of the score of tests) when adjusted for confounders including lower limb RASM. Grade 2 and 3 and multiple vertebral fractures were associated with twofold higher risk of multiple falls after adjustment for confounders. Men having multiple fractures had a twofold higher risk of multiple falls after adjusting for confounders. In multivariable models, risk of falls increased proportionally to the increasing severity and number of vertebral fractures as well as to the increasing number of all fractures.

CONCLUSIONS

In older men, Grade 2 and 3 vertebral fractures and multiple vertebral and non-vertebral fractures are associated with lower grip strength, poor physical function, and higher risk of multiple falls after adjustment for multiple confounders. This suggests a real direct association. One fracture can initiate a vicious circle leading to another fracture; thus, patients with fractures need physical therapy regardless of their general health status.

Cross-Sectional and Longitudinal Associations Between Adiposity and Walking Endurance in Adults Age 60-79

BACKGROUND

The impact of excess weight on current and future walking endurance in nondisabled persons is unclear. This study examines the association between obesity and walking endurance among nondisabled persons both in late mid-life and early old age.

METHODS

Participants in the Baltimore Longitudinal Study of Aging aged 60-79 years (n = 406) who reported no walking limitations, and completed a 400-meter walk "as quickly as possible" without lower-extremity pain, and had a follow-up assessment within 1.7-4.2 years. Adiposity was assessed by weight, body mass index (BMI), BMI category, and percent fat mass by DXA.

RESULTS

Adjusting for age, sex, race, height, and physical activity, all adiposity measures were cross-sectionally associated with slower 400 meter time in both 60-69 and 70 to 79-year-olds (weight: β = 1.0 and 1.2; BMI: β = 2.8 and 3.6; and percent fat mass: β = 2.0 and 2.0, respectively, all p < .001). With additional adjustment for initial 400-meter performance and follow-up time, in 60- to 69-year-olds, change in 400-meter time (positive β indicates decline) was associated with all adiposity measures (weight: β = 0.4; BMI: β = 1.0; and percent fat mass: β = 0.5; all p ≤ .05) but not in the older group (weight: β = -0.4; BMI: β = -1.2; and percent fat mass: β = -0.2; all p ≥ .17).

CONCLUSION

Excess weight and adiposity were associated with worse walking endurance in nondisabled persons aged 60-79 years and predicted accelerated decline in endurance in late mid-life adults. Weight management for mobility independence may be best targeted in obese persons approaching traditional retirement age.

Influência do estado nutricional, distribuição da gordura corporal e força muscular na estabilometria de idosas

OBJETIVO: Investigar as associações entre diversas medidas indicadoras do estado nutricional, a força muscular e as diferentes variáveis estabilométricas em uma amostra de idosas. MÉTODOS: Neste estudo exploratório de corte transversal, 108 idosas tiveram suas variáveis estabilométricas avaliadas através de uma plataforma de força, em duas condições experimentais: olhos abertos e olhos fechados. Verificaram-se as associações entre as variáveis explicativas: idade, massa corporal, estatura, índice de massa corporal, circunferência de quadril, circunferência de cintura, relação cintura/quadril, percentual de gordura corporal, massa gorda, massa magra, área muscular de braço corrigida, força isométrica voluntária máxima e diversas variáveis estabilométricas: amplitude anteroposterior, deslocamento da oscilação e área elíptica da superfície, dentre outras. RESULTADOS: Com exceção da estatura, todas as variáveis explicativas associaram-se significativamente com as variáveis estabilométricas. A regressão múltipla (forward) revelou que a circunferência de cintura e a força isométrica voluntária máxima foram as variáveis que mais influenciaram as variáveis estabilométricas, entretanto sem diferenças significativas entre as condições olhos abertos e olhos fechados. O percentual de gordura parece não sobrecarregar o sistema de controle postural. Na condição olhos abertos, a variável estabilométrica desvio--padrão médio-lateral foi a mais influenciada pelas variáveis explicativas. A circunferência de cintura foi respon-sável por 8,8% de toda variação do desvio-padrão médio-lateral e a força isométrica voluntária máxima contribuiu com 9,4% adicionais. CONCLUSÃO: Os resultados sugerem que a distribuição centrípeta de gordura corporal associada à diminuição da força muscular são as principais responsáveis pelas alterações estabilométricas em idosas.

Sex-specific relationships of physical activity, body composition, and muscle quality with lower-extremity physical function in older men and women

OBJECTIVE

This study aims to determine the sex-specific relationships of physical activity, body composition, and muscle quality with lower-extremity physical function in older men and women.

METHODS

Seventy-nine community-dwelling men (n = 39; mean [SD] age, 76.1 [6.2] y; mean [SD] body mass index, 27.3 [3.8] kg/m(2)) and women (n = 40; mean [SD] age, 75.8 [5.5] y; mean [SD] body mass index, 27.0 [3.8] kg/m(2)) were assessed for physical activity via questionnaire, body composition via dual-energy x-ray absorptiometry scanning, leg extension power using the Nottingham power rig, and muscle quality (W/kg; the ratio of leg extension power [W] to lower-body mineral-free lean mass [kg]). A composite measure of physical function was obtained by summing Z scores from the 6-minute walk, 8-ft up-and-go test, and 30-second chair-stand test.

RESULTS

As expected, men had significantly greater levels of physical activity, lower adiposity, greater lean mass, higher leg extension power, and greater muscle quality compared with women (all P < 0.05). In linear regression analyses, muscle quality and physical activity were the strongest predictors of lower-extremity physical function in men and independently explained 42% and 29% of the variance, respectively. In women, muscle quality (16%) and percent body fat (12%) were independent predictors after adjustment for covariates.

CONCLUSIONS

Muscle quality is the strongest predictor of lower-extremity physical function in men and women, but sex impacts the importance of physical activity and adiposity. These findings suggest that older men and women may benefit from different intervention strategies for preventing physical disability and also highlight the importance of weight management for older women to preserve physical function.

Association of adiposity and muscle quality with physical function differs in young and old women

OBJECTIVE

This study aims were to investigate whether age differentially impacts the relationships between adiposity, muscle quality (MQ), and lower-extremity physical function in young and older women.

METHODS

Women aged 20 to 30 years (YOUNG group; n = 37) and women aged 64 to 80 years (OLD group; n = 39) were assessed for body composition via dual-energy X-ray absorptiometry. Isokinetic strength at 60 deg/second was assessed on a dynamometer. MQ was calculated as Nm / mineral-free lean mass (kg). Lower-extremity physical function was determined by an up-and-go (UPGO) challenge.

RESULTS

YOUNG women had lower relative adiposity (%Fat), greater leg lean mass, greater MQ, and faster UPGO time compared with OLD women (all P < 0.01). On linear regression analyses, mineral-free upper leg lean mass was the strongest predictor of UPGO performance in YOUNG women and independently explained 36% of the variance; in OLD women, age and adiposity were the strongest predictors and explained 57% and 40% of the variance, respectively.

CONCLUSIONS

Predictors of lower-extremity physical function differ between young and old women. These findings suggest that body composition and muscle capacity factors associated with function might change across the age span.

Evaluation of the Usefulness of Consensus Definitions of Sarcopenia in Older Men: Results from the Observational Osteoporotic Fractures in Men Cohort Study

OBJECTIVE

To evaluate the associations between definitions of sarcopenia and clinical outcomes and the ability of the definitions to discriminate those with a high likelihood of having these outcomes from those with a low likelihood.

DESIGN

Osteoporotic Fractures in Men Study.

SETTING

Six clinical centers.

PARTICIPANTS

Community-dwelling men aged 65 and older (N = 5,934).

MEASUREMENTS

Sarcopenia definitions from the International Working Group, European Working Group on Sarcopenia in Older Persons, Foundation for the National Institutes of Health Sarcopenia Project, Baumgartner, and Newman were evaluated. Recurrent falls were defined as two or more self-reported falls in the year after baseline (n = 694, 11.9%). Incident hip fractures (n = 207, 3.5%) and deaths (n = 2,003, 34.1%) were confirmed according to central review of medical records over 9.8 years. Self-reported functional limitations were assessed at baseline and 4.6 years later. Logistic regression or proportional hazards models were used to estimate associations between sarcopenia and falls, hip fractures, and death. The discriminative ability of the sarcopenia definitions (vs reference models) for these outcomes was evaluated using area under the receiver operating characteristic curve or C-statistics. Referent models included age alone for falls, functional limitations and mortality, and age and bone mineral density for hip fractures.

RESULTS

The association between sarcopenia according to the various definitions and risk of falls, functional limitations, and hip fractures was variable; all definitions were associated with greater risk of death, but none of the definitions materially changed discrimination based on the AUC and C-statistic when compared with reference models (change ≤1% in all models).

CONCLUSION

Sarcopenia definitions as currently constructed did not consistently improve prediction of clinical outcomes in relatively healthy older men.

Body Weight Dynamics Following Intentional Weight Loss and Physical Performance: The Look AHEAD Movement and Memory Study

Objective

The aim of this study was to explore the impact of body weight change following intentional weight loss on measures of physical performance in adults with diabetes.

Design and methods

Four hundred fifty individuals with type 2 diabetes (age, 59.0 ± 6.9 years; body mass index, 35.5 ± 5.9 kg/m²) who participated in the Look AHEAD Movement and Memory Study and lost weight 1 year after being randomized to an intensive lifestyle intervention were assessed. Body weight was measured annually, and participants were categorized as continued losers/maintainers, regainers, or cyclers based on a ±5% annual change in weight. Objective measures of physical performance were measured at the year 8/9 visit.

Results

Forty‐four percent, 38% and 18% of participants were classified as regainers, cyclers, and continued losers/maintainers, respectively. In women, weight cycling and regain were associated with worse follow‐up expanded physical performance battery score (1.46 ± 0.07 and 1.48 ± 0.07 vs. 1.63 ± 0.07, both p ≤ 0.02) and slower 20‐m walking speed (1.10 ± 0.04 and 1.08 ± 0.04 vs. 1.17 ± 0.04 m/s, both p < 0.05) compared with continued or maintained weight loss. Male cyclers presented with weaker grip strength compared with regainers or continued losers/maintainers (30.12 ± 2.21 vs. 34.46 ± 2.04 and 37.39 ± 2.26 kg; both p < 0.01).

Conclusions

Weight cycling and regain following intentional weight loss in older adults with diabetes were associated with worse physical function in women and grip strength in men.

Higher Leptin and Adiponectin Concentrations Predict Poorer Performance-based Physical Functioning in Midlife Women: the Michigan Study of Women's Health Across the Nation

BACKGROUND

Excess fat mass is a greater contributor to functional limitations than is reduced lean mass or the presence of obesity-related conditions. The impact of fat mass on physical functioning may be due to adipokines, adipose-derived proteins that have pro- or anti-inflammatory properties.

METHODS

Serum samples from 1996 to 2003 that were assayed for leptin, adiponectin, and resistin were provided by 511 participants from the Michigan site of the Study of Women's Health Across the Nation. Physical functioning performance was assessed annually during study visits from 1996 to 2003.

RESULTS

Among this population of Black and White women (mean baseline age = 45.6 years, SD = 2.7 years), all of whom were premenopausal at baseline, higher baseline leptin concentrations predicted longer stair climb, sit-to-rise, and 2-pound lift times and shorter forward reach distance (all p < .01). This relationship persisted after adjustment for age, BMI, percent skeletal muscle mass, race/ethnicity, economic strain, bodily pain, diabetes, knee osteoarthritis, and C-reactive protein. Baseline total adiponectin concentrations did not predict any mobility measures but did predict quadriceps strength; a 1 µg/mL higher adiponectin concentration was associated with 0.64 Nm lower quadriceps strength (p = .02). Resistin was not associated with any of the physical functioning performance measures. Change in the adipokines was not associated with physical functioning.

CONCLUSION

In this population of middle-aged women, higher baseline leptin concentrations predicted poorer mobility-based functioning, whereas higher adiponectin concentrations predicted reduced quadriceps strength. These findings suggest that the relationship between the adipokines and physical functioning performance is independent of other known correlates of poor functioning.

Comparison of body composition, nutritional status, functional status, and quality of life between osteoporotic and osteopenic postmenopausal women

BACKGROUND AND OBJECTIVE

Osteoporosis is a condition that affects body composition, physical activity, and psychological state. We aimed to examine the differences between osteoporotic and osteopenic postmenopausal women with respect to body composition, nutrition, functional status, and quality of life.

MATERIALS AND METHODS

A total of 102 osteopenic (Group 1) and 100 osteoporotic (Group 2) patients were enrolled in the study. Bone mineral density (BMD), fat tissue mass (FTM), lean tissue mass (LTM), and bone mineral content (BMC) were evaluated using dual-energy X-ray absorbtiometry. Nutritional status of the patients was assessed with the Mini Nutritional Assessment (MNA), functional status with the Nottingham Extended Activities of Daily Living (NEADL) scale, and quality of life with the assessment of health-related quality of life in osteoporosis (ECOS-16).

RESULTS

Group 2 had significantly lower FTM, LTM, and MNA scores than Group 1 (P<0.05). NEADL and ECOS-16 scores did not differ between the groups (P>0.05). A significant correlation was found between MNA and FTM, LTM, BMC, and BMD (P<0.05). Whereas the assessment of functional status showed a significant positive correlation with BMD and a significant negative correlation with age (P<0.05), no significant correlation was found between functional status and body composition (P>0.05).

CONCLUSIONS

We found lower FTM and LTM values and a poorer nutritional status in osteoporotic patients than in osteopenic ones. Nutritional status was correlated with body composition and BMD, and functional status was correlated with age and BMD.