Cross-calibration of eight-polar bioelectrical impedance analysis versus dual-energy X-ray absorptiometry for the assessment of total and appendicular body composition in healthy subjects aged 21-82 years

Association of Predicted Visceral Fat Percentage With Dementia Risk in Older Adults: The Role of Genetic Risk and Lifestyle

BACKGROUND AND OBJECTIVES

Obesity is a modifiable dementia risk factor, but body mass index does not account for fat distribution, particularly visceral fat, which is more strongly linked to metabolic and cardiovascular health. Despite its relevance, research on visceral fat and dementia is limited, especially in large-scale prospective studies. The aim of this study was to assess the association between visceral fat and dementia risk, its interaction with genetic predisposition, and the impact of healthy lifestyle adherence.

METHODS

Using data from the UK Biobank (UKB) cohort, we computed baseline, sex-specific visceral fat percentage (VFP), defined as the ratio of visceral fat mass to total body fat mass. Nonlinear associations between VFP and incident dementia were initially assessed using restricted cubic splines. The relationship between VFP and incident dementia was further examined using Cox proportional hazard models. In addition, stratified and interaction analyses were conducted to assess dementia incidence across VFP levels, lifestyle factors, and genetic risk.

RESULTS

The study included 63,042 women (mean age: 63.96 years) and 74,001 men (64.20 years) aged 60 years and older from the UKB, with a median follow-up of 14.07 years for men and 14.09 years for women. During follow-up, 2,805 men and 1,893 women developed dementia. A U-shaped association between VFP and dementia risk was observed in both sexes. In men, each SD increase in VFP below the median value of 8.1% was associated with a reduced risk of dementia (HR: 0.90, 95% CI 0.85-0.96), whereas above the median, the risk increased (1.06, 1.00-1.11). Similarly, in women, below the median VFP value of 3.1%, each SD increase was linked to a decreased dementia risk (0.89, 0.83-0.96), and above the median, the risk increased (1.14, 1.07-1.22). No significant interactions were found between VFP and genetic risk or lifestyle factors.

DISCUSSION

Among nondemented, community-dwelling older Britons, atypical VFP was associated with higher dementia risk in both sexes. The lack of interaction between VFP and genetic risk highlights the complexity of dementia pathogenesis. In addition, a healthy lifestyle may mitigate the dementia risk associated with atypical VFP levels.

Total and regional fat-to-muscle mass ratio and risks of pan-cancer: a prospective cohort study

BACKGROUND

The fat-to-muscle mass ratio (FMR) has served as a marker for various diseases. This study aimed to explore sex-specific associations between FMR in different body regions (whole body, trunk, arm, and leg) and cancer incidence.

METHODS

We included 435,986 cancer-free participants (203,133 men and 232,853 women) from the UK Biobank at baseline. FMR was calculated as the ratio of fat mass to muscle mass in each body region. Multivariable Cox proportional hazards models, along with Cox models incorporating restricted cubic splines (RCS) function, were employed to examine both linear and non-linear associations between FMR and cancer risk in men and women. Additionally, a combined grouping of body mass index (BMI) and FMR was used to assess the joint impact of body composition on cancer incidence.

RESULTS

During the follow-up period, 62,060 new cancer cases were recorded. Our analysis showed significant associations between both total and regional FMR and the risk of several cancers. In men, higher whole body FMR was associated with an increased risk of esophagus, stomach, colorectal, liver, pancreas, and kidney cancers, while a decreased risk was observed for prostate and non-melanoma skin cancers (FDR < 0.05). In women, higher FMR was associated with a higher incidence of gallbladder, pancreas, kidney, thyroid, breast, and uterus cancers (FDR < 0.05). Non-linear associations were observed for several cancer types, with specific FMR cut-off points presented using RCS curves. The analysis by combining BMI and FMR suggested potential interaction patterns, revealing some masked risks; for example, a significant increase in cancer incidence was also observed in individuals exhibiting high FMRs despite having low BMI.

CONCLUSIONS

Our findings suggested that both total and regional FMR may serve as potential biomarkers for assessing the risk of overall and site-specific cancers.

Frequency, intensity and duration of physical activity is associated with frailty in older adults with cardiac aging

While cardiovascular aging and frailty are strongly associated in older adults, their mechanistic relationship and how physical activity, through its frequency, intensity, and duration, may influence their association remains unclear. A prospective community cohort of older adults without cardiovascular disease were studied cross-sectionally for cardiac structure and function via echocardiogram, dynamometer-derived handgrip strength, skeletal muscle measurements and physical activity questionnaires. Based on handgrip strength and cardiac aging, we derived four phenotypic groups:1 Normal2, Physical frailty without cardiac aging3, Cardiac aging without physical frailty, and4 Physical frailty and cardiac aging. Multinomial logistic regression was used to examine factors associated with cardiac frailty phenotypes, adjusting for physical activity characteristics, physical measurements, demographics, and cardiovascular risk factors. Amongst 592 participants, the prevalence in the four groups were 44.9%, 20.6%, 18.8%, and 15.7% respectively. Participants in group 1 were the youngest (64, IQR 22), while those in group 4 were the oldest (75, IQR 4.7). Higher frequencies of physical activity (once a week: RRR = 8.922, 95%CI 1.799, 44.250, p = 0.007; and 2-3 times a week: RRR = 3.873, 95%CI 1.036, 14.478, p = 0.044) were associated with Group 4 category. Higher intensity of physical activity indicated by heavy breath and sweat or near exhaustion (RRR = 0.081, 95%CI 0.017, 0.380, p = 0.001), and longer duration (> 1 h: RRR = 0.261, 95%CI 0.079, 0.869, p = 0.029) were associated with Group 4 category as well. More than half of community older adults had physical frailty with or without cardiac aging. Higher intensity and longer physical activity duration were associated with lower risks of cardiac aging in the presence of physical frailty, although frequency of once and two to three times a week was associated with higher odds. Physical activity frequency showed no significant association with risks of isolated cardiac aging or physical frailty. These results highlight the importance of tailoring physical activity characteristics based on cardiac frailty phenotypes for developing individualized preventive interventions. Trial registration: ClinicalTrials.gov Identifier: NCT02791139 (06/06/2016).

Association of Muscle Strength, Psychological Factors, and Central Sensitization With Movement-Evoked Pain in Patients With Nonspecific Chronic Low Back Pain: The BACKFIT Project

BACKGROUND

People with chronic pain might evade certain movements to prevent their experience of pain. Movement-evoked pain (MEP) might induce lower functionality during daily activities.

HYPOTHESIS

(1) MEP after physical fitness tests would vary depending on the main musculature involved in the test; (2) physical and psychological factors would be associated with MEP in patients with NSCLBP.

STUDY DESIGN

Cross-sectional design.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 104 (69 women) patients aged 51.0 ± 10.3 years with NSCLBP participated. MEP was measured with a visual analog scale (VAS) at baseline and immediately after performing each physical fitness test, that is, the Biering-Sørensen, prone bridging, handgrip, chair-stand, and 8-foot time-up-and-go tests, measuring back extensor, back flexor, upper- and lower-body muscle strength, and motor agility, respectively. Global muscle strength was calculated with normalized index (z-score) procedure. Depression, anxiety, pain catastrophizing, and central sensitization were assessed with the Beck Depression Inventory II, State Trait Anxiety Inventory I, Pain Catastrophizing Scale, and Central Sensitization Inventory (CSI), respectively.

RESULTS

Patients showed greater pain after completion of the Biering-Sørensen (mean difference 95% CI, 0.02, 1.11), prone bridging (0.15, 1.21), lower pain after handgrip (-1.46, -0.52), and the 8-foot time-up-and-go (-1.43, 0.46) tests (all P ≤ 0.04). Lower global muscular strength (β between -0.18 and -0.30), and greater pain catastrophizing (β = 0.16), and CSI scoring (β between 0.18 and 0.27) were associated with greater MEP (all P ≤ 0.04).

CONCLUSION

Greater MEP was observed after tests measuring core musculature strength than after tests measuring distal (limbs) strength and agility. Greater MEP was overall associated with lower muscle strength, greater pain catastrophizing, and central sensitization.

CLINICAL RELEVANCE

Fitness testing might be implemented as a complementary tool for the monitoring of NSCLBP in clinical settings.

Associations between muscle quality and whole-body vibration exercise-induced changes in plasma hypoxanthine following an oral glucose load in healthy male subjects

Blood levels of hypoxanthine (HX) have been suggested as potential biomarkers associated with intramuscular metabolic dynamics in response to exercise. This pilot randomized crossover trial (UMIN000036520) aimed to investigate the changes in plasma HX after whole-body vibration exercise (WBVE) and their relationships with body composition and muscle-related parameters, enrolling eighteen healthy male volunteers. In the WBVE-alone intervention, the study subjects performed 20-min of WBVE. In the OGTT → WBVE intervention, a 75-g oral glucose load (OGL) was administered 30 min prior to the start of the WBVE intervention. Blood samples were collected before the start and 10 min after the end of WBVE in both interventions. WBVE resulted in a significant increase in plasma HX levels, which was accompanied by increased blood ammonia, pyruvic acid, and lactic acid levels. The HX increase following WBVE was suppressed by prior OGL. In the WBVE-alone intervention, there were no significant correlations between the post-WBVE changes in plasma HX (ΔHX) levels and any of the clinical parameters. On the other hand, in the OGTT → WBVE intervention, ΔHX showed significant negative correlations with muscle mass (ρ = -0.62, p = 0.01), strength (ρ = -0.71, p = 0.005), and muscle quality (ρ = -0.81, p = 0.0007) in the legs. In conclusion, these findings suggest possible associations between post-WBVE increases in plasma HX levels and muscle status, particularly under the glucose-supplemented condition. The measurement of plasma HX concentrations following WBVE may have clinical applications in the identification of high-risk populations for sarcopenia.

Effect of home-based hot bathing on exercise-induced adaptations associated with short-term resistance exercise training in young men

This study investigated whether home-based bathing intervention (HBBI) improve muscle strength gain and protect cardiovascular function by short-term resistance training (RT). Thirty-one healthy young men measured the maximum voluntary isometric contraction (MVC) of knee extensor, electrically evoked knee extension torque, and mean arterial pressure (MAP). Then, participants were divided into three groups with matching MVC: shower without bathing (control, n = 10), thermoneutral bathing (36°C-bathing, n = 10), and hot bathing (40°C-bathing, n = 11), and conducted 2 weeks of HBBI. Following familiarization for HBBI, participants completed 2 weeks of HBBI and acute RT (five sessions of three sets of 10 isometric knee extension at 60% MVC). Baseline neuromuscular and cardiovascular function was assessed again following completion of the 2 weeks of intervention. MVC was non-significantly increased after the RT period in 40°C-bathing with large effect size (partial η2 = 0.450). The electrically evoked knee extension torque (10/100-Hz ratio) was significantly increased after the RT period in control (p = 0.020). MAP did not alter due to bathing intervention and RT (all p > 0.05). HBBI improved muscle strength without RT-induced alteration of peripheral muscle condition. Shower without bathing reduced muscle strength gain but increased peripheral muscle condition. Short-term RT does not adversely affect the cardiovascular function, regardless of HBBI.

Muscle Mass Index Decline as a Predictor of Lung Function Reduction in the General Population

BACKGROUND

This study explores the link between muscle mass decline and lung function deterioration, which can worsen respiratory health by reducing exercise capacity and quality of life. The relationship between muscle mass index (MMI) changes and lung function in the general population remains unclear, especially as muscle mass fluctuates with aging. We aimed to clarify this dynamic relationship by examining how changes in muscle mass impact pulmonary function and the development of respiratory symptoms.

METHODS

We utilized the Ansan and Ansung Cohort Study of the Korean Genome and Epidemiology Study (KoGES) database, a large-scale prospective cohort, enrolling participants aged 40 to 69 years with lung function and body composition measurements. Over 12 years, data were collected biannually. The study assessed associations between changes in MMI and lung function trends, with cT1-T3 calculated using the linear regression coefficient and stratified by tertile. Survival analysis was then performed to examine differences in time to first airflow obstruction (AFO) and exacerbation among the tertiles.

RESULTS

A total of 2956 participants were enrolled in this study. At baseline, participants with higher MMI tended to be younger, had fewer co-morbidities and exhibited better lung function. Those with a steeper MMI decline rate exhibited a more rapid forced expiratory volume in 1 s (FEV1) decline over a 12-year follow-up (cT1: 43.3 mL/year, cT2: 38.4 mL/year, cT3: 33.2 mL/year, p < 0.001). Forced vital capacity (FVC) decline were more pronounced in groups with greater MMI decline rates (cT1: 38.5 mL/year, cT2: 32.8 mL/year, cT3: 26.0 mL/year, p < 0.001). Although, the time to first AFO did not differ significantly among T1-T3 groups, the time to first exacerbation related to wheezing event was significantly lower in cT3 group than in cT1 group (HR: 0.786, 95% CI: 0.629, 0.982).

CONCLUSIONS

A faster decline in MMI was associated with more rapid decline of both FEV1 and FVC and a higher risk of developing exacerbations of respiratory symptom. Although AFO was not associated with changes in MMI, further research is needed to explore the long-term relationships between muscle mass and the effects of preventive interventions aimed at maintaining muscle mass and respiratory health.

Metagenomic Analysis Identifies Sex-Related Gut Microbial Functions and Bacterial Taxa Associated With Skeletal Muscle Mass

BACKGROUND

This study aimed to explore the association between gut microbiota functional profiles and skeletal muscle mass, focusing on sex-specific differences in a population under 65 years of age.

METHODS

Stool samples from participants were analysed using metagenomic shotgun sequencing. Skeletal muscle mass and skeletal muscle mass index (SMI) were quantified (SMI [%] = total appendage muscle mass [kg]/body weight [kg] × 100) using bioelectrical impedance analysis. Participants were categorized into SMI quartiles, and associations between gut microbiota, functional profiling and SMI were assessed by sex, adjusting for age, BMI and physical activity.

RESULTS

The cohort included 1027 participants (651 men, 376 women). In men, Escherichia coli (log2 fold change 3.08, q = 0.001), Ruminococcus_B gnavus (log2 fold change 2.89, q = 0.014) and Enterocloster sp001517625 (log2 fold change 2.47, q = 0.026) were more abundant in the lowest SMI compared to the highest SMI group. In contrast, Bifidobacterium bifidum (log2 fold change 3.13, q = 0.025) showed higher levels in the second lowest SMI group in women. Microbial pathways associated with amino acid synthesis (MET-SAM-PWY: log2 fold change 0.42; METSYN-PWY: log2 fold change 0.44; SER-GLYSYN-PWY: log2 fold change 0.20; PWY-5347: log2 fold change 0.41; P4-PWY: log2 fold change 0.53), N-acetylneuraminate degradation (log2 fold change 0.43), isoprene biosynthesis (log2 fold change 0.20) and purine nucleotide degradation and salvage (PWY-6353: log2 fold change 0.42; PWY-6608: log2 fold change 0.38; PWY66-409: log2 fold change 0.52; SALVADEHYPOX-PWY: log2 fold change 0.43) were enriched in the lowest SMI in men (q < 0.10). In women, the second lowest SMI group showed enrichment in energy-related pathways, including lactic acid fermentation (ANAEROFRUCAT-PWY: log2 fold change 0.19), pentose phosphate pathway (PENTOSE-P-PWY: log2 fold change 0.30) and carbohydrate degradation (PWY-5484: log2 fold change 0.31; GLYCOLYSIS: log2 fold change 0.29; PWY-6901: log2 fold change 0.27) (q < 0.05).

CONCLUSIONS

This study highlights sex-specific differences in gut microbiota and functional pathways associated with SMI. These findings suggest that gut microbiota may play a role in muscle health and point toward microbiota-targeted strategies for maintaining muscle mass.

Body composition and physical performance of mountain bike athletes

Body composition is a determining factor in the physical performance of cyclists, directly influencing efficiency and power during competitions. Understanding these aspects can help optimize training and maximize results. This study aimed to analyze the influence of body composition on physical performance in mountain bike athletes. His cross-sectional study evaluated 83 mountain bike athletes (11 females, 39.60 ± 11.52 years). Body composition assessment was carried out using bioimpedance analysis. Participants performed the standing long jump and handgrip strength tests, to assess their strength of the lower and upper limbs, respectively. Finally, we measured the completion time of a Mountain Bike Marathon, with the distance of 75 km). Pearson's correlation was analyzed to verify the influence of body composition on race time and physical performance tests. The race time was 168.14 ± 30.85 min. Standing long jump and handgrip strength tests were significantly correlated with all body composition parameters. Additionally, race time was significantly correlated with body fat percentage (r = 0.415, p = 0.000), skeletal muscle mass (r = - 0.427, p = 0.000), total body water (r = - 0.400, p = 0.000), intracellular water (r = - 0.420, p = 0.000), and extracellular water (r = - 0.370,p = 0.000). Body composition has a significant influence on the physical performance of mountain bike cyclists, with body water and muscle mass positively correlated with performance and body fat negatively correlated. A higher percentage of fat results in longer race times, while greater muscle mass and hydration result in shorter race times.

Age-related changes in bioelectrical impedance analysis-derived phase angle (PhA) and the association between PhA and sarcopenic obesity in Chinese adults

There are limited studies on the phase angle (PhA) and sarcopenic obesity (SO) in the Chinese population. This study aimed to establish 50 kHz-PhA reference data for SO population, and to evaluate the correlation between 50 kHz-PhA and SO. A total of 10,312 participants including 5415 men and 4897 women were enrolled in this study, and their resistance and reactance at 50 kHz, and body composition parameters were measured a segmental multifrequency bioelectrical impedance analysis device (InBody 720). Participants were compared between the SO and non-SO groups. Then, age and fat parameters related changes in PhA were evaluated. Furthermore, Receiver Operating Characteristic (ROC) curves were used to identify the optimal PhA cutoff values for detecting SO in males and females. The results showed significant differences in PhA and body composition parameters between the SO group and the non-SO group in both sexes (P < .001), and the prevalence rates of SO increase with age in both sexes (P < .001). The PhA values decrease with age, with a significant decrease beginning at age 65 years for males and 66 years for females. The accumulation of excess adipose tissue was also found to be associated with decrease in 50 kHz-PhA value. Furthermore, PhA was negatively associated with SO, independent of age and sex. The area under the ROC curve (AUC) of PhA for SO was 0.790 (95% CI: 0.746-0.833, P < .001) in males and 0.763 (95% CI: 0.702-0.825, P < .001) in females. The optimal cutoff value was ≤ 5.55° (specificity 0.693, sensitivity 0.759) for males and ≤4.79° (specificity 0.687, sensitivity 0.738) for females. In conclusion, 50 kHz-PhA can be used as a predictor of SO, with cutoff values of ≤5.55° for males and ≤4.79° for females. This simple and practical method of using 50 kHz-PhA to predict SO could be valuable in clinical practice.

Alcohol consumption after downhill running does not affect muscle recovery but prolongs pain perception in East Asian men

PURPOSE

Alcoholic beverages are commonly consumed following athletic competitions and strenuous exercise for celebration or relaxation purposes. Whether and how alcohol consumption influences muscle recovery and perceived pain following unaccustomed eccentric exercise is unclear. We aimed to determine the effects of alcohol consumption after downhill running on muscular strength and perceived pain in East Asian men.

METHODS

Twenty-four young men performed 45 min of downhill (-10%) running at a corresponding speed of 70% VO2 max. Immediately after downhill running and again 24 h later, the participants consumed either an alcoholic beverage (1 g ethanol/kg body weight, alcohol group, n=12) or the same quantity of water (control group, n=12).

RESULTS

Peak isometric and concentric muscle contraction torques during knee extension (via the isokinetic dynamometer) and squat jump height decreased 24 h after downhill running (all p<0.05); however, there were no significant differences between the two groups. The visual analog scores for pain (pain scores) in the quadriceps, hamstring, gastrocnemius, and gluteus maximus muscles increased at 24 h and 48 h in both groups (all p<0.05). Pain scores in the quadriceps decreased gradually from 24 h to 48 h in the control group, but no such trend was observed in the alcohol group (group × time interaction effect; F=4.47, p<0.05).

CONCLUSION

Acute alcohol consumption does not seem to affect muscle strength or jump performance during recovery. However, the effects on pain appear to persist longer after alcohol consumption in East Asian men.

Differences in Fibromyalgia Characteristics by Mode of Commute and Age in Women: The Al-Ándalus Project

OBJECTIVES

This study aimed to test whether fibromyalgia-related characteristics differ by mode of commute and by age in women with fibromyalgia.

METHODS

A total of 450 women with fibromyalgia (aged 52.0 ± 8.0 years old) were included. Data on their body composition, socioeconomic factors, health-related quality of life (HRQoL), depressive symptoms, sleep quality, pain-related outcomes, fatigue, and mode of commute, as well as the impact of fibromyalgia on their lives, were obtained. We performed linear regression analyses to test the differences in fibromyalgia-related characteristics between the participants engaged in active/passive modes of commuting. To analyze in depth the differences, a one-way analysis of covariance with Bonferroni's correction for multiple comparisons was conducted.

RESULTS

In the younger group, active commuters presented differences in fibromyalgia-related characteristics (all, p < 0.01): they were less impacted by having fibromyalgia, had lower levels of fatigue, and had a higher HRQoL than passive commuters. We observed no differences in symptoms between active and passive commuters in the older group (all, p > 0.05).

CONCLUSIONS

The possible positive effect of active commuting on fibromyalgia-related characteristics might be reduced by age and by a decrease in total physical activity. Physical activity programs for women with fibromyalgia focused on improving fibromyalgia-related characteristics should consider active commuting behaviors to increase their effectiveness.

Comparing Device-Generated and Calculated Bioimpedance Variables in Community-Dwelling Older Adults

Despite BIA emerging as a clinical tool for assessing older adults, it remains unclear how to calculate whole-body impedance (Z), reactance (Xc), resistance (R), and phase angle (PhA) from segmental values using modern BIA devices that place electrodes on both sides of the body. This investigation aimed to compare both the whole-body and segmental device-generated phase angle (PhADG) with the phase angle calculated using summed Z, Xc, and R from the left, right, and combined sides of the body (PhACalc) and to compare bioelectric variables between sides of the body. A sample of 103 community-dwelling older adults was assessed using a 50 kHz direct segmental multifrequency BIA device. Whole-body PhACalc values were assessed for agreement with PhADG using 2.5th and 97.5th quantile nonparametric limits of agreement and Spearman's rho. Bioelectrical values between sides of the body were compared using Wilcoxon rank and Spearman's rho. A smaller mean difference was observed between PhADG and right PhACalc (-0.004°, p = 0.26) than between PhACalc on the left (0.107°, p = 0.01) and on the combined sides (0.107°, p < 0.001). The sum of Z, R, and PhACalc was significantly different (p < 0.01) between the left (559.66 ± 99.55 Ω, 556.80 ± 99.52 Ω, 5.51 ± 1.5°, respectively) and the right sides (554.60 ± 94.52 Ω, 552.02 ± 94.23 Ω, 5.41 ± 0.8°, respectively). Bilateral BIA values do not appear to be interchangeable when determining whole-body measurements. Present data suggest that using right-sided segmental values would be the most appropriate choice for calculating whole-body bioelectrical variables.

Open, Active-Controlled Clinical Study to Evaluate the Correlation between Whole Body DEXA and BIA Muscle Measurements

BACKGROUND

Dual energy X-ray absorptiometry (DXA) is the gold standard for diagnosing sarcopenia. However, comparative studies using bioelectrical impedance analysis (BIA) would be required in the Korean population. This study aimed to evaluate the correlation between total-body bone density measuring devices (Hologic and GE Lunar) and a bioelectrical impedance measurement device (InBody 970) as well as the correlation between upper body muscle mass.

METHODS

A total of 119 participants were involved in this study, aged 20 to 70 years, with specific body mass index ranges and no severe health conditions used both DXA (or DEXA) and BIA technologies to assess body composition. The participants were scanned using a Hologic QDR-4500W DXA scanner and GE-Lunar Prodigy DXA systems, and the InBody 970 type of multi-frequency BIA machine. Statistical analysis was performed to determine the correlation between the devices, with a coefficient of at least 0.8.

RESULTS

The muscle mass measurement comparisons between the InBody 970 and Hologic devices demonstrated remarkably high correlation coefficients (exceeding 0.9) across all limbs. Similarly, the muscle mass comparison between the Inbody 970 and GE Lunar devices also revealed substantial correlation coefficients, ranging from 0.83 upwards, across all limbs.

CONCLUSIONS

Limb muscle mass measurements using Hologic and GE Lunar whole-body DXA and Inbody 970 BIA demonstrated particularly high levels of concordance. In addition, a conversion formula that bridges limb muscle mass measurements from two widely used whole-body DXA machines and a BIA machine will facilitate sarcopenia research and patient management.

Sex Differences in the Association between Prolonged Sitting Time and Anxiety Prevalence among Korean Adults

Sex differences in the effect of prolonged sitting time on anxiety symptoms have not yet been explored. This study examined the sex-specific association between prolonged sitting time and anxiety prevalence in Korean adults. Community-dwelling adults aged >18 years who underwent a cross-sectional structured study survey of physical activity and mental health tests were enrolled as part of the Kangbuk Samsung Hospital Cohort Study from 2012 to 2019. The prevalence of anxiety was evaluated using the Clinically Useful Anxiety Outcome Scale (CUXOS) questionnaire. The mean daily sitting time was 7.9 ± 3.4 h in men and 6.8 ± 3.6 h in women. After adjustments for possible confounding factors, the adjusted mean CUXOS score was the highest in participants sitting for ≥10 h, followed by 5-9 h, and <5 h, in that order. In the post-hoc Bonferroni analysis, there were significant differences in the adjusted mean CUXOS scores in group comparisons. A multivariate logistic regression analysis was conducted after adjusting for potential confounding factors. A prolonged sitting time was positively associated with an increased prevalence of anxiety in both men and women, with stronger associations in women than in men. It is necessary to prevent anxiety by adjusting or reducing sitting time in adults, especially women.

Associations of activity, sedentary and sleep behaviors with prevalent steatotic liver disease in middle-aged and older adults: the ELSA-Brasil study

BACKGROUND

Steatotic liver disease (SLD) is a prevalent metabolic disease. While single component movement behaviors have been related to its development, comprehensive assessments of their joint associations are scarce.

OBJECTIVE

To investigate the single-component and multi-component associations of moderate and vigorous physical activity (MVPA), light physical activity (LPA), sedentary behavior (SB), and sleep with prevalent SLD in Brazilian adults.

METHODS

A cross-sectional analysis using data from the third wave of the ELSA-Brasil cohort (2017-2019). Participants wore an ActiGraph wGT3X-BT in the waist for seven days and completed a sleep diary. SLD was defined by a Fatty Liver Index ≥ 60. To investigate single-component and multi-component associations, we used three exposure modeling approaches based on Poisson models: multivariable-adjusted regression, restricted cubic splines, and compositional data analysis.

RESULTS

Among 8569 participants (55.7% women, mean age 59.2 ± 8.60), 43.9% had SLD. Total activity volume adjusted for covariates was inversely associated with prevalent SLD. Every 1 mg/day increase in total activity volume was associated with a PR of 0.95 in individuals sleeping < 7 h/day (95% CI 0.94-0.97) and 0.95 (95% CI 0.93-0.96) in those sleeping ≥ 7 h/day. Increasing 30 min/day of MVPA was associated with decreasing prevalence of SLD (sleep ≥ 7 h/day [PR 0.83; 95% CI 0.77-0.89]; sleep ≥ 7 h/day [PR 0.78; 95% CI 0.74-0.83]). Sleep, SB, and LPA were not associated with SLD. Associations of total activity volume and MVPA were more pronounced among females. Adjustment with adiposity markers attenuated the associations.

CONCLUSIONS

In adults, total activity volume and MVPA were inversely associated with SLD in a dose-response fashion. Substituting lower-intensity behaviors with MVPA was associated with a lower prevalence of SLD independent of sleep duration, sex, and age.

Phase angle as an indicator of body composition and physical performance in handball players

BACKGROUND

Phase angle (PhA), obtained from the bioimpedance analysis, is widely used in clinical situations and in sports. This study evaluated the association between PhA with body composition and physical performance of handball athletes.

METHODS

43 national-level players (22.19 ± 3.86 years) of both sexes were evaluated regarding anthropometry, body composition, squat (SJ) and countermovement (CMJ) jumps, handgrip strength, and cardiorespiratory fitness.

RESULTS

We verified a correlation between PhA of the whole body and fat-free mass (r = 0.511), body mass index (r = 0.307), and body fat % (r = -0.303). There was a positive correlation between PhA of the whole body and SJ (r = 0.376), CMJ (r = 0.419), and handgrip for the dominant hand (r = 0.448). Moreover, PhA of the upper limbs was more strongly correlated with handgrip for the dominant (r = 0.630) and non-dominant hand (r = 0.575) compared to PhA of the whole body considering both sexes. Similarly, segmental PhA had a stronger significant correlation with SJ (r = 0.402) and handgrip for the dominant hand (r = 0.482) in males, as well as CMJ (r = 0.602) in females, compared to PhA of the whole body.

CONCLUSION

PhA of the whole body was positively related to fat-free mass, body mass index, body fat %, and lower- and upper-limbs strength in handball athletes. Segmental PhA might be used as a tool for estimating lower and upper limbs performance considering the sex, in preference to the PhA of the whole body.

Frailty in Midlife as a Predictor of Changes in Body Composition from Midlife into Old Age: A Longitudinal Birth Cohort Study

INTRODUCTION

Few studies have investigated the association between frailty and subsequent body composition.

METHODS

We performed separate linear mixed model analyses to study the associations between changes in the participant frailty status assessed by a frailty index (FI) and subsequent body mass index (BMI), lean mass index (LMI), fat mass index (FMI), and FMI to LMI ratio values assessed on three occasions over 17 years. The analyses were carried out among 996 participants spanning from age 57 to 84 years.

RESULTS

With advancing age, LMI and BMI decreased, whereas FMI and FMI to LMI ratio increased. Participants with "stable frailty," followed by those with "increasing frailty" experienced faster decreases in LMI and faster increases in FMI and FMI to LMI ratio values from midlife into old age relative to those in the group "stable not frail." Contrastingly, those in the highest third of absolute annual increase in FMI and FMI to LMI ratio became more frail faster from midlife into old age relative to those in the lowest third.

CONCLUSIONS

We found evidence of an adverse health outcome of frailty where lean indices declined faster and fat indices and fat-to-lean ratios increased faster from midlife into old age. The changes resembled those that occurred with aging, but at a faster pace. The relationship between body composition and frailty is likely bidirectional, where high or increasing levels of fat are associated with the risk of becoming more frail earlier, but where a longer duration of frailty may increase the risk of faster age-related changes to body composition.

Association of Moderate-to-Vigorous Physical Activity, Sedentary Time, Fat Percentage, and Physical Fitness with Gait Parameters in Women with Fibromyalgia: The Al-Ándalus Project

Gait impairments have been found in women with fibromyalgia, reducing the physical activity possibilities in this population and leading to a negative correlation with fibromyalgia impact. The aim of this study was to analyze the individual and independent associations of moderate-to-vigorous physical activity (MVPA), sedentary time, fat percentage, and physical fitness with gait parameters in women with fibromyalgia. A total of 84 women with fibromyalgia were included. MVPA and sedentary time were assessed with accelerometry, fat percentage with bioimpedance analysis, and physical fitness with field-based fitness tests. Gait was assessed during a "6 min walk test" and categorized in velocity, cadence, step length, step cycle duration, unipedal stance phase, and bipedal stance phase. Individual relationships were analyzed by partial correlations and independent relationships by linear regressions, adjusting by age and height. MVPA, sedentary time, fat percentage, and physical fitness were correlated with most gait parameters (rpartial between |0.842| and |0.219|; p ≤ 0.05). Physical fitness was independently associated with all gait parameters (β between |0.346| and |0.761|; p ≤ 0.002). In addition, MVPA was independently associated with velocity and step length (β = 0.241 and 0.292; both p = 0.004), and fat percentage was associated with bipedal stance phase (β = 0.242; p = 0.049). Good levels of MVPA, physical fitness, and adequate weight balance are associated with improved gait parameters in women with fibromyalgia.

Impact of Low Bone Mineral Content Index on Cardiovascular Outcomes in Patients With Coronary Artery Disease Undergoing Percutaneous Coronary Intervention

The prognostic value of bone mineral content (BMC) for the clinical outcomes of patients with coronary artery disease (CAD) remains unknown. The present study evaluated the association between BMC index (BMCI) and cardiovascular events between January 2020 to June 2021, in consecutive patients (n = 257) with CAD undergoing percutaneous coronary intervention (PCI) at the Nagano Municipal Hospital. BMCI was measured using bioelectrical impedance analysis and calculated as the BMC divided by height squared. Patients were classified as low (<0.918) or high BMCI (≥0.918) groups according to the receiver operating characteristics curve analysis for the primary endpoint, major adverse cardiovascular events (MACE), including cardiovascular death, spontaneous myocardial infarction, stroke, and any revascularization. During a median follow-up of 744 days, the low BMCI group (n = 152) had an increased risk of MACE compared with the high group (n = 105) (19.7 vs 6.7%, P = .004). A low BMCI was significantly associated with MACE in the multivariable Cox and the Inverse Probability of Treatment Weighting analyses (hazard ratio: 3.16, 95% confidence interval: 1.15-8.67, P = .025). In conclusion, among patients with CAD undergoing PCI, BMCI was a predictor for cardiovascular events. Further research is required to determine whether medical interventions for BMC can improve patient prognosis.

Comprehensive evaluation of body composition in a wide age range of Iranian adults using bioelectrical impedance analysis: Tehran Lipid and Glucose Study

OBJECTIVE

To evaluate sex- and age-stratified body composition (BC) parameters in subjects with wide age range of 20-79 years.

DESIGN

Cross-sectional.

SETTING

Participants of Tehran Lipid and Glucose Study (TLGS).

PARTICIPANTS

Two thousand nine hundred seventy participants met our inclusion criteria. They were divided into five age groups, and BC parameters were analysed based on sex and age using a bioelectrical impedance analyser (BIA).

RESULT

The mean age of the participants was 42·1 ± 12·5 years, and 54 % of them were males. The mean BMI was 26·7 ± 3·7 kg/m2. Obesity indices were significantly higher in females (P < 0·001); however, skeletal muscle mass (SMM) and fat-free mass (FFM) were significantly higher in males (P < 0·001). Both SMM and FFM decreased significantly after the age of 50 years. Obesity indices significantly increased from the age group of 20-29 to 30-39 years in males and the age groups of 30-39 to 40-49 years and 40-49 to 50-59 years in females. The fat mass ratio (fat mass/SMM) showed two peaks in both sexes (after the ages of 30 and 50 years in males and 40 and 50 years in females). A strong correlation was found between BMI and percentage of body fat (r = 0·823 in females v. r = 0·768 in males).

CONCLUSION

This is the first community-based study in the MENA region identifying sex- and age-stratified BC values using BIA. Our findings can be used as a reference for comparison in appropriate settings.

Longitudinal profiling and tracking stability in the Singapore study of macro-angiopathy and microvascular reactivity in type 2 diabetes cohort

INTRODUCTION

The Singapore Study of Macro-Angiopathy and microvascular Reactivity in Type 2 Diabetes (SMART2D) is a prospective cohort study which was started in 2011 to investigate the effect of risk factors on vascular function and diabetes-related complications in Asians. We aimed to compare the longitudinal change in risk factors by accounting for batch effect and assess the tracking stability of risk factors over time in patients recruited for SMART2D. In this study, we (1) described batch effect and its extent across a heterogenous range of longitudinal data parameters; (2) mitigated batch effect through statistical approach; and (3) assessed the tracking stability of the risk factors over time.

METHODS

A total of 2258 patients with type 2 diabetes mellitus (T2DM) were recruited at baseline. The study adopted a three-wave longitudinal design with intervals of 3 years between consecutive waves. The changes in a few selected risk factors were assessed after calibration, assuming patients with similar demographic and anthropometry profile had similar physiology. The tracking pattern of the risk factors was determined with stability coefficients derived from generalised estimating equations.

RESULTS

The medians of the longitudinal differences in risk factors between the waves were mostly modest at <10%. Larger increases in augmentation index (AI), aortic systolic blood pressure (BP) and aortic mean BP were consistently observed after calibration. The medians of the longitudinal differences in AI, aortic systolic BP and aortic mean BP between the waves were <2% before calibration, but increased slightly to <5% after calibration. Most of the risk factors had moderate to high tracking stability. Muscle mass and serum creatinine were among those with relatively high tracking stability.

CONCLUSIONS

The longitudinal differences in parameters between the waves were overall modest after calibration, suggesting that calibration may attenuate longitudinal differences inflated by non-biological factors such as systematic drift due to batch effect. Changes of the hemodynamic parameters are robust over time and not entirely attributable to age. Our study also demonstrated moderate to high tracking stability for most of the parameters.

Associations of artificially sweetened beverages, sugar-sweetened beverages, and pure fruit/vegetable juice with visceral adipose tissue mass

OBJECTIVE

To test the associations of sugar-sweetened beverage, artificially sweetened beverage, and pure fruit/vegetable juice consumption with visceral adipose tissue (VAT) mass at baseline and follow-up and to determine whether BMI and genetic risk of VAT mass modified the associations.

METHODS

A total of 203,348 participants from UK Biobank with consumption data on three beverages were included. Participants were categorized into nonconsumers and consumers with >0-1, >1-2 and >2 L/week. A sex-specific prediction model was used to calculate VAT mass. A weighted genetic risk score for high VAT mass was calculated.

RESULTS

The participants with a sugar-sweetened beverage and artificially sweetened beverage consumption of >2 L/week had the greatest B values [B (95% CI): 24.02 (16.53, 31.51) and 60.81 (52.08, 69.54) in men, respectively; 10.20 (5.92, 14.48) and 24.72 (20.80, 28.64) in women]. Low and moderate intake of pure fruit/vegetable juices showed a significantly inverse association with VAT mass in men [-10.52 (-15.37, -5.67); -6.46 (-11.27, -1.65)] and women [-6.70 (-8.99, -4.41); -5.93 (-8.33, -3.54)]. Regarding changes in VAT mass, participants who consumed >2 L/week of sugar-sweetened beverages and artificially sweetened beverages had greater changes. BMI but not genetic risk modified the associations between beverage intake and VAT mass, which were strengthened in participants with BMI ≥25 kg/m2 for sugar-sweetened and artificially sweetened beverage consumption.

CONCLUSIONS

Higher consumption of sugar-sweetened beverages or artificially sweetened beverages was associated with greater VAT mass regardless of genetic risk. Mild-to-moderate intake of pure fruit/vegetable juices was linked to lower VAT mass.

Total and Regional Fat/Muscle Mass Ratio and Risks of Incident Cardiovascular Disease and Mortality

Background To evaluate the sex-specific associations of total and regional fat/muscle mass ratio (FMR) with cardiovascular disease (CVD) incidence and mortality, and to explore the underlying mechanisms driven by cardiometabolites and inflammatory cells. We compared the predictive value of FMRs to body mass index. Methods and Results This population-based, prospective cohort study included 468 885 UK Biobank participants free of CVD at baseline. Fat mass and muscle mass were estimated using a bioelectrical impedance assessment device. FMR was calculated as fat mass divided by muscle mass in corresponding body parts (total body, trunk, arm, and leg). Multivariable Cox proportional hazards models and mediation analyses were used. During 12.5 years of follow-up, we documented 49 936 CVD cases and 4158 CVD deaths. Higher total FMR was associated with an increased risk of incident CVD (hazard ratios [HRs] were 1.63 and 1.83 for men and women, respectively), ischemic heart disease (men: HR, 1.61; women: HR, 1.81), myocardial infarction (men: HR, 1.72; women: HR, 1.49), and congestive heart failure (men: HR, 2.25; women: HR, 2.57). The positive associations of FMRs with mortality from total CVD or its subtypes were significant mainly in trunk and arm for male patients (P for trend <0.05). We also identified 8 cardiometabolites and 5 inflammatory cells that partially mediated FMR-CVD associations. FMRs were modestly better at discriminating cardiovascular mortality risk. Conclusions Higher total and regional FMRs were associated with an increased risk of CVD and mortality, partly mediated through cardiometabolites and inflammatory cells. Early monitoring of FMR should be considered to alleviate CVD risk. FMRs were superior to body mass index in predicting CVD mortality.

Relationships Between Skeletal Muscle Mass, Lumbar Lordosis, and Chronic Low Back Pain in the Elderly

OBJECTIVE

Loss of skeletal muscle mass is known to be associated with multiple morbidities. However, there is a dearth of reports on its association with lumbar lordosis and musculoskeletal pain. The aim of this study was to delineate the cross-sectional relationship between loss of skeletal muscle mass, lumbar lordosis, and chronic low back pain (CLBP).

METHODS

A total of 721 medical records were reviewed, and data from 165 older subjects (over 65 years old; 81 men and 84 women) were retrospectively analyzed. Subjects were categorized into either the CLBP group (back pain for more than 6 months; 35 men and 36 women) or the control group (46 men and 48 women). The modified skeletal muscle mass index (MSMI, appendicular skeletal muscle mass [kg]/weight [kg] × 100), assessed by bioelectrical impedance analysis, and lumbar lordotic angle (LLA) were measured and compared between the CLBP group and the control group. The correlation between MSMI and LLA was investigated.

RESULTS

The LLA of men and women in the CLBP group was significantly lower than that of the control group (p < 0.05). The MSMI was decreased in the CLBP group compared to the control group (p < 0.05). For both sexes, positive correlations were observed between the MSMI and LLA.

CONCLUSION

A close cross-sectional relationship was observed between MSMI, LLA, and CLBP. This suggests a potential interaction between the reduction in skeletal muscle mass and altered lumbar spine sagittal alignment, which could lead to CLBP.

Body Composition in Late Midlife as a Predictor of Accelerated Age-associated Deficit-accumulation From Late Midlife into Old Age: A Longitudinal Birth Cohort Study

BACKGROUND

Body mass index (BMI) may not be an optimal predictor of frailty as its constituents, lean and fat mass, may have opposite associations with frailty.

METHODS

A linear mixed model analysis was performed in the Helsinki Birth Cohort Study (n = 2 000) spanning from 57 to 84 years. A 39-item frailty index (FI) was calculated on three occasions over 17 years. Body composition in late midlife included BMI, percent body fat (%BF), waist-to-hip ratio (WHR), lean mass index (LMI), and fat mass index (FMI).

RESULTS

Mean FI levels increased by 0.28%/year among men and by 0.34%/year among women. Among women, per each kg/m2 higher BMI and each unit higher %BF the increases in FI levels per year were 0.013 percentage points (PP) steeper (95% CI = 0.004, 0.023) and 0.009 PP steeper (95% CI = 0.002, 0.016) from late midlife into old age. Among men, per each 0.1-unit greater WHR the increase in FI levels was 0.074 PP steeper per year (95% CI = -0.0004, 0.148). Cross-sectionally, greater FMI and LMI in late midlife were associated with higher FI levels but the direction of the association regarding LMI changed after adjustment for FMI. The categories "high FMI and high LMI" and "high FMI and low LMI" showed the highest FI levels relative to the category "low FMI and low LMI".

CONCLUSIONS

In late midlife, greater adiposity (%BF) among women and abdominal obesity (WHR) among men may predispose to higher levels of frailty from late midlife into old age. Greater lean mass alone may be protective of frailty, but not in the presence of high fat mass.

The impact of insulin resistance on the association between metabolic syndrome and lung function: the Kangbuk Samsung Health Study

BACKGROUND/OBJECTIVE

Metabolic syndrome (MS) is related to lung dysfunction. However, its impact according to insulin resistance (IR) remains unknown. Therefore, we evaluated whether the relation of MS with lung dysfunction differs by IR.

SUBJECT/METHODS

This cross-sectional study included 114,143 Korean adults (mean age, 39.6 years) with health examinations who were divided into three groups: metabolically healthy (MH), MS without IR, and MS with IR. MS was defined as presence of any MS component, including IR estimated by HOMA-IR ≥ 2.5. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for lung dysfunction were obtained in MS, MS without IR, and MS with IR groups compared with the MH (reference) group.

RESULTS

The prevalence of MS was 50.7%. The percent predicted forced expiratory volume in 1 s (FEV1%) and forced vital capacity (FVC%) showed statistically significant differences between MS with IR and MH and between MS with IR and MS without IR (all P < 0.001). However, those measures did not vary between MH and MS without IR (P = 1.000 and P = 0.711, respectively). Compared to MH, MS was not at risk for FEV1% < 80% (1.103 (0.993-1.224), P = 0.067) or FVC% < 80% (1.011 (0.901-1.136), P = 0.849). However, MS with IR was clearly associated with FEV1% < 80% (1.374 (1.205-1.566) and FVC% < 80% (1.428 (1.237-1.647) (all p < 0.001), though there was no evident association for MS without IR (FEV1%: 1.078 (0.975-1.192, P = 0.142) and FVC%: 1.000 (0.896-1.116, p = 0.998)).

CONCLUSION

The association of MS with lung function can be affected by IR. However, longitudinal follow-up studies are required to validate our findings.

Effects of a 14-week community health program of exercise and learning/education in older adults: A single-arm pre-post comparison study

This study was initiated in 2022 in Miyaki Town, Saga Prefecture, Japan, to determine the impact of an intervention that combined brain and physical function training and health education in older residents. Miyaki has a population of approximately 26,000, 35% of whom are considered to be aging. A 14-week program consisting of strength training, brain function training, and health lectures was conducted with 34 older residents of the community. Body composition, motor function, brain function, and various blood tests were evaluated before and after the intervention. Brain function was assessed using the Trail Making Test-A. Physical function was assessed by Open-Close Stepping, Functional Reach Test, Open-Leg Standing Time, and Two-Step Test. The intervention group showed significant improvements in brain function (p< 0.0001), physical function (p = 0.0037), body composition (p = 0.0053), and LDL-C (p = 0.017). This study provides substantial evidence that community-based combined programs can be beneficial for older adults.

Age-specific and sex-specific associations of visceral adipose tissue mass and fat-to-muscle mass ratio with risk of mortality

BACKGROUND

Limited studies have explored the association between visceral adipose tissue (VAT) mass and fat-to-muscle mass ratio (FMR) and mortality. We aimed to evaluate the sex-specific association of VAT and FMR with all-cause and cause-specific mortality by age.

METHODS

A total of 438 896 participants (49.8% men, mean age ± standard deviation: 57 ± 8 years for men; 56 ± 8 years for women) were included from the UK Biobank cohort. The nature of VAT was predictive, as obtained by sex-stratified, non-linear prediction models. Fat and muscle mass were estimated using a bioelectrical impedance assessment device. FMR was calculated as the fat mass divided by the muscle mass in the whole body. VAT and FMRs were divided into quintiles in ascending order, and the 3rd quintile was used as the reference. Cox regression analyses were used to estimate the associations between VAT, FMR and mortality.

RESULTS

During a median of 12.4 years of follow-up, we documented 29 903 deaths. After adjusting for various covariates, the individuals in the highest quintiles of VAT and FMR had the highest hazard ratios (HRs) of all-cause mortality [1.24 (95% confidence interval: 1.17-1.33) for VAT and 1.24 (1.17-1.31) for FMR in men; and 1.11 (1.03-1.21) for VAT in women], except that the 1st quintile of FMR in women had the greatest HR [1.18 (1.09-1.27)]. Significant interactions were observed in both sexes according to age category (P for interaction < 0.05). Among men <50 years, participants in the 1st and 5th quintiles of VAT and FMR had significantly higher risks of mortality [1.30 (1.02-1.66) and 1.67 (1.27-2.19) in VAT; 1.25 (0.99-1.56) and 1.41 (1.11-1.79) in FMR, respectively]; in women, this phenomenon was observed in the ≥60 age group [1.16 (1.06-1.27) and 1.19 (1.08-1.31) in VAT; 1.18 (1.08-1.29) and 1.11 (1.01-1.22) in FMR, respectively]. VAT showed a linear positive association with mortality in women <60 years and a J-shaped association from respiratory disease in both sexes ≥60 years. FMR showed a linear positive association with mortality from cancer in men <60 years and a J-shaped association with mortality from cause-specific mortality in both sexes ≥60 years, except for mortality from cardiovascular disease in men.

CONCLUSIONS

Most associations of VAT and FMR with all-cause mortality were J-shaped and were significantly modified by age status (<50, 50-59 and ≥60 years). The clinical implication is that regarding body composition and VAT mass, different health strategies may be adopted for people of different sexes and ages.

Sex-specific associations between gut microbiota and skeletal muscle mass in a population-based study

BACKGROUND

A gut-muscle axis through which the microbiome influences skeletal muscle has been hypothesized. However, sex-specific association between the characteristics of gut microbiota and skeletal muscle mass has not yet been reported. Herein, we performed sex-specific analyses of faecal microbiota composition for the skeletal muscle mass in a population-based cohort.

METHODS

We collected faecal samples of 1052 middle-aged participants (621 men and 431 women) who attended health screenings, and we analysed the intestinal microbiota using 16S rRNA gene sequencing. Relative muscle mass was calculated using a bioelectrical impedance analysis and presented as the skeletal muscle mass index [SMI (%) = total appendicular muscle mass (kg)/weight (kg) × 100]. We categorized the subjects into four groups by the quartile of the SMI. Association tests between gut microbiota and SMI were conducted according to the microbial diversity, taxonomic profiling and functional inference in a sex-stratified manner.

RESULTS

The mean age and SMI of the total participants were 44.8 years (standard deviation [SD], 8.2) and 41.4% (SD, 3.9), respectively. After adjustments for possible covariates such as age, body mass index and regular physical activity, the highest quartile (Q4) group of SMI had higher alpha diversity than the lowest quartile (Q1) group in male participants (coefficient = 10.79, P < 0.05, linear regression model), whereas there was no difference in diversity among SMI groups in females. At the species level, Haemophilus parainfluenzae (coefficient = 1.910) and Roseburia faecis (coefficient = 1.536) were more abundant in the highest SMI (Q4) group than in the lowest SMI (Q1) group in males. However, no significant taxon was observed along the SMI groups in females. The gut microbiota of the lowest SMI group (Q1) was enriched with genes involved in biosynthesis of amino acids and energy generation compared with that of the highest SMI group (Q4) in both sexes, although the significance of the inferred pathways was weak (P < 0.05 but the false discovery rate q > 0.05).

CONCLUSIONS

In this large sample of middle-aged individuals, this study highlights fundamental sex-specific differences in the microbial diversity, composition and metabolic pathways inferred from gut microbiota according to SMI. The gut microbiota may provide novel insights into the potential mechanisms underlying the sex dependence of skeletal muscle mass.

Gradual Strength Training Improves Sleep Quality, Physical Function and Pain in Women with Fibromyalgia

BACKGROUND

Fibromyalgia (FM) is characterized by chronic and generalized musculoskeletal pain. There is currently no cure for FM, but alternative treatments are available. Among them, gradual strength training programs (ST) which on daily activities are a valid option to improve some of the pronounced symptoms of FM that affect quality of life, such as fatigue, pain, sleep quality, and physical function. However, there is a need for more information on optimal training programs to improve anxiety and fatigue symptoms.

AIM

To analyze the effects of a 24-week gradual and progressive ST on sleep quality, fatigue, pain domains, physical function, and anxiety-state.

METHODS

41 women with FM participated in the 24 weeks of intervention based on gradual and progressive ST. Two, 60 min, training sessions per week were con-ducted. Participants were evaluated before the ST program (week 0), in week 12 and at the end of the ST program (week 24). The Revised Fibromyalgia Impact Questionnaire was used to assess sleep quality and fatigue scales. Anxiety-state was evaluated with the State Anxiety Inventory, and pain domains by means of the Brief Pain Inventory. Senior Fitness Test was used for physical function measurements. One-way analysis of variance (ANOVA) was applied to assess the mean differences between phases, and Spearman's correlations were used to assess the associations between physical and psychological symptoms, and physical function.

RESULTS

The results demonstrated that 24 weeks of ST improves physical function, sleep quality and pain domains (p ≤ 0.05). Higher anxiety and pain interference scores were related to worsening physical function.

CONCLUSIONS

Gradual ST significantly improves sleep quality, pain, and physical function, but not anxiety and fatigue.

Influence of Upper-Extremity and Lower-Extremity Resistance Exercise on Segmental Body Composition and Body Fluid Estimates

ABSTRACT

Rodriguez, C, Florez, CM, Prather, J, Zaragoza, J, Tinnin, M, Brennan, KL, Taylor, L, and Tinsley, GM. Influence of upper-extremity and lower-extremity resistance exercise on segmental body composition and body fluid estimates. J Strength Cond Res XX(X): 000-000, 2022-The purpose of this analysis was to determine if acute, localized resistance exercise (RE) artificially influences total and regional estimates of body composition from dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA). Recreationally active male (n = 14) and female (n = 18) subjects completed 3 testing visits: rest (R), upper-extremity RE (U), and lower-extremity RE (L). Dual-energy X-ray absorptiometry scans were completed before exercise and 60 minutes after exercise. Bioelectrical impedance analysis was completed immediately before and after exercise and at 15, 30, and 60 minutes after exercise. Subjects were not allowed to intake fluid during the exercise session or during the postexercise assessment period. The effects of the acute RE session on DXA and BIA estimates were analyzed using linear mixed-effects models with a random intercept for subject. Condition by time interactions were observed for most BIA outcomes. Relative to the reference model (i.e., R condition at baseline), total body water and fat-free mass estimates were, on average, approximately 1 and approximately 1.2 kg higher, in the U condition. In contrast, lower-extremity RE exerted little or no impact on most BIA variables. Some DXA estimates exhibited time main effects, but the magnitude of changes was negligible. An acute bout of localized RE, particularly upper-extremity RE, can artificially influence BIA body fluid and composition estimates, whereas DXA may be robust to the acute biological error introduced by RE. Although body composition assessments should ideally be conducted under standardized conditions, DXA may be suitable in less standardized situations. In addition, BIA is differentially influenced by upper-extremity and lower-extremity resistance exercise.

Influence of the nutritional status on facial morphology in young Japanese women

Evidence regarding the possible influence of nutritional status on the facial morphology has thus far been insufficient. We examined whether or not the physical body compositions and dietary behaviors were correlated with any morphological characteristics of the face. One hundred and fifteen young Japanese women participated. Variables representing the dietary behaviors were extracted from self-reported survey data, and corresponding three-dimensional (3D) facial images and body compositions were examined. Multivariate analyses identified significant relationships between the nutritional status and facial topography (p < 0.05). The clustering method revealed the existence of three dietary condition patterns ("balanced diet", "high-calorie-diet" with obesity tendency, and "imbalanced low-calorie-diet" with sarcopenic obesity tendency). Among these three patterns, a round face (increased facial width; analysis of variance [ANOVA], p < 0.05) was observed in the high-calorie-diet pattern, while the imbalanced low-calorie-diet pattern showed a more masculine face (increased face height, decreased eye height, increased non-allometric sexual shape differences; ANOVA, p < 0.05), thus suggesting the possibility of sex-hormonal influences. In summary, the body composition and dietary behaviors were found to influence the facial morphology, and potential biological influences were discussed.

Metabolically healthy and unhealthy obesity and risk of vasomotor symptoms in premenopausal women: cross-sectional and cohort studies

Objective

To examine the relationship between metabolically healthy and unhealthy obesity phenotypes and risk of vasomotor symptoms (VMS) in premenopausal women.

Design

Prospective cohort study.

Setting

Middle‐aged women in a cohort based on regular health screening examinations.

Population

Premenopausal Korean women aged 42–52 years were recruited and were followed up for a median of 4.2 years. The cross‐sectional and cohort studies comprised 4672 women and 2590 women without VMS at baseline, respectively.

Methods

Adiposity measures included body mass index (BMI), waist circumference and percentage body fat. Being metabolically healthy was defined as not having any metabolic syndrome components or a homeostasis model assessment of insulin resistance of 2.5 or more.

Main outcomes measures

VMS (hot flushes and night sweats) assessed using the questionnaire.

Results

All adiposity measures were positively associated with an increased risk of VMS in both cross‐sectional and longitudinal studies. The multivariable‐adjusted prevalence ratio (95% confidence interval [CI]) for VMS comparing percentage body fat of 35% or more with the reference was 1.47 (95% CI 1.14–1.90) in metabolically healthy women, and the corresponding prevalence ratio was 2.32 (95% CI 1.42–3.78) in metabolically unhealthy women (P_interaction = 0.334). The multivariable‐adjusted hazard ratio for incident VMS comparing percentage body fat of 35% or more with the reference was 1.34 (95% CI 1.00–1.79) in metabolically healthy women, whereas the corresponding hazard ratio was 3.61 (95% CI 1.81–7.20) in metabolically unhealthy women (P_interaction = 0.036). The association between BMI, waist circumference and VMS did not significantly differ by metabolic health status.

Conclusions

Maintaining normal weight and being metabolically healthy may help to prevent VMS in premenopausal women.

Tweetable abstract

Avoiding obesity and a metabolically unhealthy status may help reduce vasomotor symptoms in premenopausal women.

Avoiding obesity and a metabolically unhealthy status may help reduce vasomotor symptoms in premenopausal women.

The importance of muscle mass in predicting intradialytic hypotension in patients undergoing maintenance hemodialysis

Background

Patients undergoing hemodialysis are susceptible to sarcopenia. As intracellular reservoirs of water, skeletal muscles are important contributors to intradialytic hypotension. This study was designed to determine the role of skeletal muscle mass in intradialytic hypotension.

Methods

In a cross-sectional study, the body composition of 177 patients was measured immediately after hemodialysis using bioelectrical impedance analysis. The parameters measured were skeletal muscle mass, intracellular and extracellular water contents, total body water, and cell-membrane functionality (in phase angle at 50 kHz). Data from laboratory tests, chest radiography, measurements of handgrip strength and mid-arm circumference, and questionnaires were collected. The main outcome was intradialytic hypotension, defined as more than two episodes of hypotension (systolic blood pressure of <90 mmHg) with intervention over the 3 months following enrollment. Logistic regression models including each parameter related to sarcopenia were compared with a clinical model.

Results

Patients with a low ratio of skeletal muscle mass to dry body weight (SMM/WT) had a higher rate of intradialytic hypotension (41%). Most low-SMM/WT patients were female, obese, diabetic, and had a lower handgrip strength compared with the other patients. In the high-SMM/WT group, the risk of intradialytic hypotension was lower, with an odds ratio of 0.08 (95% confidence interval [CI], 0.02-0.28) and adjusted odds ratio of 0.06 (95% CI, 0.01-0.29).

Conclusion

Measurement and maintenance of skeletal muscle can help prevent intradialytic hypotension in frail patients undergoing hemodialysis.

Adiposity-Related Predictors of Vascular Aging From a Life Course Perspective–Findings From the Helsinki Birth Cohort Study

The main objective of this study was to study predictors of vascular health with focus on adiposity-related factors. Glucose metabolism, blood lipids, inflammatory markers and body composition were assessed 15 years before assessment of vascular health which was assessed with pulse wave velocity (PWV) in 660 subjects born 1934–44. In a univariate analysis in women the strongest association with PWV was seen for age, systolic blood pressure, dysglycemia, dyslipidemia, inflammatory markers and body fat percentage measured in late midlife and PWV measured 15 years later. In men age, body mass index (BMI), systolic blood pressure, dysglycemia, and body fat percentage in late midlife were associated with PWV. One novel finding was that adiposity-related factors were strong predictors of vascular health, something not fully encapsulated in BMI, lean body mass or body fat percentage alone. A higher fat mass index was associated with worse vascular health, which was not ameliorated by a higher lean mass index. Our findings stress the importance to study body composition and fat and lean body mass simultaneously because of their close interaction with each other also in relation to vascular health.

The effect of metabolic health and obesity on lung function: A cross sectional study of 114,143 participants from Kangbuk Samsung Health Study

Objective

Although the role of obesity-induced metabolic abnormalities in impaired lung function is well-established, the risk of impaired lung function among obese individuals without metabolic abnormalities, referred to metabolically-healthy obesity (MHO), is largely unexplored. Therefore, we evaluated the impact of MHO on lung function in a large health-screening cohort.

Methods

114,143 subjects (65,342 men, mean age and BMI: 39.6 years and 23.6) with health examinations in 2019 were divided into four groups as follows: metabolically healthy non-obese (MHNO), MHO, metabolically unhealthy non-obese (MUHNO), and metabolically unhealthy obese (MUHO). Metabolic health was defined as fewer than two metabolic syndrome components. Obesity was defined as BMI ≥25 kg/m². Adjusted odds ratios (aORs), using MHNO as a reference, were calculated to determine lung function impairment.

Results

Approximately one-third (30.6%) of the study subjects were obese. The prevalence of MHO was 15.1%. Subjects with MHO had the highest FEV1% and FVC% values but the lowest FEV1/FVC ratio (p<0.001). These results persisted after controlling for covariates. Compared with MHNO, the aORs (95% confidence interval) for FEV1% < 80% in MHO, MUHNO and MUHO were 0.871 (0.775–0.978), 1.274 (1.114–1.456), and 1.176 (1.102–1.366), respectively (P for trend = 0.014). Similarly, the aORs in MHO, MUHNO, and MUHO were 0.704 (0.615–0.805), 1.241 (1.075–1.432), and 1.226 (1.043–1.441), respectively, for FVC% < 80% (p for trend = 0.013). However, the aORs for FEV1/FVC<0.7 were not significantly different between groups (p for trend = 0.173).

Conclusions

The MHO group had better lung function than other groups. However, longitudinal follow-up studies are required to validate our findings.

Amino acid profile of skeletal muscle loss in type 2 diabetes: Results from a 7-year longitudinal study in asians

AIMS

Little is known about pathophysiology of sarcopenia in diabetes. We aimed to study amino acid profile associated with skeletal muscle mass loss longitudinally in Type 2 Diabetes Mellitus (T2DM).

METHODS

This is a prospective study of 1140 patients aged 56.6 ± 10.6 years from the SMART2D cohort. Skeletal muscle mass was measured using bio-impedance analysis at baseline and follow-up. Amino acids were measured by mass spectrometry.

RESULTS

Over a period of up to 7.9 years, 43.9% experienced skeletal muscle mass loss. Lower baseline valine, leucine and isoleucine levels were associated with decreased skeletal muscle mass index (SMI) with corresponding coefficient 0.251(95 %CI 0.009 to 0.493), 0.298(95 %CI 0.051 to 0.544)) and 0.366(95 %CI 0.131 to 0.600). Higher baseline valine, leucine, isoleucine, alanine and tryptophan levels were associated with reduced odds of muscle mass loss with corresponding odds ratio (OR)0.797 (95 %CI 0.690 to 0.921), 0.825 (95 %CI 0.713 to 0.955), 0.826 (95 %CI 0.718-0.950), 0.847 (95 %CI 0.739-0.969) and 0.835 (95 %CI 0.720-0.979).

CONCLUSION

The branched-chain amino acids valine, leucine and isoleucine were positively associated with change in SMI and reduced odds of muscle mass loss longitudinally. Further studies should be conducted to elucidate the pathophysiological mechanisms underlying the relationship between these amino acids and muscle mass loss in T2DM.

Serum 25-hydroxy vitamin D and the risk of low muscle mass in young and middle-aged Korean adults

OBJECTIVE

Despite the known benefit of vitamin D in reducing sarcopenia risk in older adults, its effect against muscle loss in the young population is unknown. We aimed to examine the association of serum 25-hydroxy vitamin D [25(OH)D] level and its changes over time with the risk of incident low muscle mass (LMM) in young and middle-aged adults.

DESIGN

This study is a cohort study.

METHODS

The study included Korean adults (median age: 36.9 years) without LMM at baseline followed up for a median of 3.9 years (maximum: 7.3 years). LMM was defined as the appendicular skeletal muscle (ASM) mass by body weight (ASM/weight) of 1 s.d. below the sex-specific mean for the young reference group. Cox proportional hazard models were used to estimate hazard ratios (HRs) with 95% CIs.

RESULTS

Of the 192,908 individuals without LMM at baseline, 19,526 developed LMM. After adjusting for potential confounders, the multivariable-adjusted HRs (95% CIs) for incident LMM comparing 25(OH)D levels of 25-<50, 50-<75, and ≥75 nmol/L to 25(OH)D <25 nmol/L were 0.93 (0.90-0.97), 0.85 (0.81-0.89), and 0.77 (0.71-0.83), respectively. The inverse association of 25(OH)D with incident LMM was consistently observed in young (aged <40 years) and older individuals (aged ≥40 years). Individuals with increased 25(OH)D levels (<50-≥50 nmol/L) or persistently adequate 25(OH)D levels (≥50 nmol/L) between baseline and follow-up visit had a lower risk of incident LMM than those with persistently low 25(OH)D levels.

CONCLUSIONS

Maintaining sufficient serum 25(OH)D could prevent unfavourable changes in muscle mass in both young and middle-aged Korean adults.

Weight Change and the Development of Nonalcoholic Fatty Liver Disease in Metabolically Healthy Overweight Individuals

INTRODUCTION

The study sought to investigate the effect of weight change on hepatic steatosis (HS) incidence with or without liver fibrosis in metabolically healthy overweight or obese individuals.

METHODS

A cohort of 14,779 metabolically healthy men and women who were overweight or obese (body mass index ≥23 kg/m²) and free from HS and an intermediate or high probability of fibrosis at baseline were followed for a median of 5.2 years. Metabolic health was defined as freedom from the components of metabolic syndrome and a homeostatic model assessment of insulin resistance <2.5. Weight changes were calculated as differences from baseline at the next subsequent visit. The outcome was HS incidence, with or without liver fibrosis, as assessed by liver ultrasound and 2 noninvasive fibrosis scores.

RESULTS

During 76,794.6 person-years of follow-up, 3539 cases of HS incidence were identified. The multivariable adjusted hazard ratios (95% confidence intervals) for HS incidence by weight change group, <-5.0%, -5.0%-1.0%, 1.0%-5.0%, and >5.0%, relative to the no weight change group (-0.9% to 0.9%) were 0.52 (0.44-0.60), 0.83 (0.75-0.92), 1.21 (1.10-1.33), and 1.51 (1.36-1.69), respectively. Clinically relevant weight loss of >5% was also associated with a lowered risk of HS with intermediate or high probability of advanced fibrosis. In mediation analyses, associations remained significant, although adjustment for metabolic risk factors was attenuating.

DISCUSSION

Clinically relevant weight loss was associated with a reduced risk of developing nonalcoholic fatty liver disease with or without intermediate or high probability of advanced fibrosis in metabolically healthy overweight or obese individuals.

Bicycle Touring 480 km in Seven Days: Effects on Body Composition and Physical Fitness-A Case Study

Bicycle touring as a modality of physical activity that involves whole-body cardiorespiratory and metabolic functions could be a potential strategy to improve body composition and cardiorespiratory fitness. Therefore, the aim of the current study was to investigate the effects of 7-days bicycle touring activity on body composition and physical fitness. A total of 13 individuals (three women) participated in this quasi-experimental study. The participants were evaluated at baseline and were tracked for up to 12 days after the intervention. The intervention consisted of a 480 km bicycle touring route performed over 8 days. Body weight and body composition (i.e., fat mass and lean mass) were assessed using a bioelectrical impedance analyser. Physical fitness was measured using the International Fitness Scale questionnaire. We conducted a repeated-measures analysis of variance to determine changes in body weight and body composition and paired sample t-tests to analyse changes in physical fitness. Significant differences in fat mass were observed between the baseline and both post-intervention (p = 0.003) and re-test values (p = 0.031). Significant differences were also noted in lean mass between the baseline and post-intervention values (p = 0.003), whereas no significant changes were observed when compared the baseline and re-test values (p = 0.178). Significant differences were obtained in cardiorespiratory fitness when comparing the baseline with the post-intervention values (p = 0.016), whereas no significant differences were noted in general fitness, muscular strength, speed/agility, and flexibility (all p > 0.05). In conclusion, a 7-day bicycle touring intervention can significantly reduce fat mass and increase lean mass and cardiorespiratory fitness in healthy individuals.

Comparison of the effects of empagliflozin and glimepiride on endothelial function in patients with type 2 diabetes: A randomized controlled study

Patients with type 2 diabetes who have cardiovascular disease and are receiving empagliflozin have a lower rate of primary composite cardiovascular outcomes. In contrast, glimepiride increases cardiovascular hospitalization when combined with metformin. Here, we assessed the effects of empagliflozin and glimepiride on endothelial function using flow-mediated dilation (FMD). In this prospective, open-label, randomized, parallel-group study, 63 patients with type 2 diabetes received metformin and insulin glargine U100 for 12 weeks. This was followed by additional treatment with empagliflozin or glimepiride for 12 weeks. The primary outcome was the change in the FMD measurement (ΔFMDs) at 24 weeks of additional treatment. Secondary outcomes comprised changes in metabolic markers and body composition. The empagliflozin group (n = 33) and glimepiride group (n = 30) showed no significant differences in ΔFMDs (empagliflozin, −0.11 [95%CI: -1.02, 0.80]%; glimepiride, −0.34 [95%CI: -1.28, 0.60]%; P = 0.73). Additionally, changes in glycated hemoglobin were similar between the two groups. However, a significant difference in body weight change was observed (empagliflozin, −0.58 [95%CI: -1.60, 0.43] kg; glimepiride, 1.20 [95%CI: 0.15, 2.26] kg; P = 0.02). Moreover, a body composition analysis revealed that body fluid volume significantly decreased after empagliflozin treatment (baseline, 35.8 ± 6.8 L; after 12 weeks, −0.33 ± 0.72 L; P = 0.03). Hence, although empagliflozin did not improve endothelial function compared with glimepiride for patients with type 2 diabetes, it did decrease body fluid volumes. Thus, the coronary-protective effect of empagliflozin is not derived from endothelial function protection, but rather from heart failure risk reduction.

Trial registration: This trial was registered on September 13, 2016; UMIN000024001.

Relationship between Seasonal Changes in Food Intake and Energy Metabolism, Physical Activity, and Body Composition in Young Japanese Women

We investigated seasonal changes in food intake, energy metabolism, and physical activity (PA) and explored their associations with body composition. In total, 28 women aged 20−23 years in the Kansai area of Japan participated in this year-long study spanning the winter, spring, and summer seasons. A dietary investigation was performed using the weight recording method, and the amount of histidine in the diet, which may be related to the regulation of energy intake, was calculated. Resting metabolic rate (RMR), body composition, and PA were measured using indirect calorimetry, bioelectrical impedance analysis, and uniaxial accelerometry, respectively. The results showed that energy intake was highest in winter, decreased significantly with increasing temperature, and decreased by 25% in summer. As the intake of histidine in the diet did not increase in summer, it did not seem to be involved in the suppression of energy intake. RMR was highest in winter and decreased significantly in summer by 20%. The amount of PA was low in winter, increased significantly in the spring, and decreased again in summer. Body weight increased in winter, with an accumulation of fat in the trunk and arms, and decreased in summer, with a reduction in the amount of fat. Greater energy intake and less PA in winter induced an increment in body weight despite the increase in RMR. There were no significant changes in lean body mass between the seasons; however, the muscle weight of the lower limbs increased significantly in spring and in summer compared with that in winter (p < 0.001). Thus, seasonal changes in food intake, energy metabolism, and PA occur, with resultant changes in the body composition under comfortable air-conditioned environments.

Excess Weight and Body Fat Percentage Associated with Waist Circumference as a Cardiometabolic Risk Factor in University Students

BACKGROUND

Obesity is one of the most important public health problems for university students. The objective of the study was to evaluate the association between body mass index (BMI) and body fat percentage (%BF) with waist circumference (WC) as a cardiometabolic risk factor (CMR) among university students.

METHODS

A cross-sectional study was carried out in 2,048 students from a private university located in Lima, Peru. Anthropometric data (weight, height, %BF, and WC) were collected. Chi-square test was used. Association analysis was performed using multiple logistic regression.

RESULTS

The findings indicated that 36.9% and 61.1% of men were overweight and had higher %BF, respectively, compared to women. Women (OR, 0.22; 95% CI, 0.17, 0.29), Peruvian students (OR, 0.59; 95% CI, 0.39, 0.90), and students enrolled in the faculty of health sciences (OR = 0.76; 95% CI, 0.62, 0.94) are less likely to manifest CMR. Also, excess body weight (OR, 17.28; 95% CI, 13.21, 22.59) and a high %BF (OR, 4.55; 95% CI, 3.55, 5.84) were strongly associated with CMR.

CONCLUSION

CMRs are a public health problem among university students. Therefore, it is important to carry out healthy lifestyle programs to promote better control and prevention, particularly among male students and those who have excess weight and body fat.

Influence of Acute Water Ingestion and Prolonged Standing on Raw Bioimpedance and Subsequent Body Fluid and Composition Estimates

This study evaluated the influence of acute water ingestion and maintaining an upright posture on raw bioimpedance and subsequent estimates of body fluids and composition. Twenty healthy adults participated in a randomized crossover study. In both conditions, an overnight food and fluid fast was followed by an initial multi-frequency bioimpedance assessment (InBody 770). Participants then ingested 11 mL/kg of water (water condition) or did not (control condition) during a 5-minute period. Thereafter, bioimpedance assessments were performed every 10 minutes for one hour with participants remaining upright throughout. Linear mixed effects models were used to examine the influence of condition and time on raw bioimpedance, body fluids, and body composition. Water consumption increased impedance of the arms but not trunk or legs. However, drift in leg impedance was observed, with decreasing values over time in both conditions. No effects of condition on body fluids were detected, but total body water and intracellular water decreased by ~0.5 kg over time in both conditions. Correspondingly, lean body mass did not differ between conditions but decreased over the measurement duration. The increase in body mass in the water condition was detected exclusively as fat mass, with final fat mass values ~1.3 kg higher than baseline and also higher than the control condition. Acute water ingestion and prolonged standing exert practically meaningful effects on relevant bioimpedance variables quantified by a modern, vertical multi-frequency analyzer. These findings have implications for pre-assessment standardization, methodological reporting, and interpretation of assessments.

Association of sleep disturbances with sarcopenia and its defining components: the ELSA-Brasil study

Sarcopenia and sleep problems share common physiopathology. We aimed to investigate the association of sleep disturbances with sarcopenia and its defining components in Brazilian middle-aged and older adults. In this cross-sectional analysis of the second wave of the ELSA-Brasil study, we included data from 7948 participants aged 50 years and older. Muscle mass was evaluated by bioelectrical impedance analysis and muscle strength by hand-grip strength. Sarcopenia was defined according to the Foundation for the National Institutes of Health criteria. Sleep duration and insomnia complaint were self-reported. Short sleep duration was considered as ≤6 h/night and long sleep duration as >8 h/night. High risk of obstructive sleep apnea (OSA) was assessed using the STOP-Bang questionnaire. Possible confounders included socio-demographic characteristics, lifestyle, clinical comorbidities, and use of sedatives and hypnotics. The frequencies of sarcopenia, low muscle mass, and low muscle strength were 1.6, 21.1, and 4.1%, respectively. After adjustment for possible confounders, high risk of OSA was associated with low muscle mass (OR=2.17, 95%CI: 1.92-2.45). Among obese participants, high risk of OSA was associated with low muscle strength (OR=1.68, 95%CI: 1.07-2.64). However, neither short nor long sleep duration or frequent insomnia complaint were associated with sarcopenia or its defining components. In conclusion, high risk of OSA was associated with low muscle mass in the whole sample and with low muscle strength among obese participants. Future studies are needed to clarify the temporal relationship between both conditions.

Impact of muscle mass on blood glucose level

OBJECTIVES

At present, diabetes is one of the leading causes of mortality across the world. It was hypothesized that muscle mass could have a significant influence on blood glucose level and this corelation if established successfully could pave way for novel treatment modalities for type 2 diabetes mellitus (T2DM). In the present study, the association between muscle mass and blood glucose level was examined in a healthy population who was not having T2DM at baseline and was undergoing a regular course of exercise.

METHODS

The clinical study was performed involving 53 healthy male populations between 10 and 60 years of age. The participants were sampled in accordance with the quantitative experimental study design, using nonprobability sampling techniques. The independent variable measured among the subjects included muscle mass and blood glucose level, using bioelectrical impedance and a simple glucometer respectively. Subgroup analysis amongst different substantial parameters including body mass index (BMI), myostatin inhibitor usage, and age factor that could affect the muscle mass and glucose level correlation were also studied simultaneously.

RESULTS

The study findings demonstrated a negative correlation between muscle mass and glucose utilization levels. There was a significant difference in the mean muscle mass of the participants which was 36.2453, and the mean glucose utilization level which was 15.1493%. Pearson correlation between the muscle mass and percentage of glucose utilization of the participants indicated a significant difference (since p-value <0.05) between these two studied parameters.

CONCLUSIONS

The study finding suggests an inverse association of the skeletal muscle mass with blood glucose level which encourages the implication of muscle-building exercises as the preventive measure for T2DM.

Total and regional fat-to-muscle mass ratio measured by bioelectrical impedance and risk of incident type 2 diabetes

BACKGROUND

The fat-to-muscle mass ratio (FMR) might be an indicator to assess type 2 diabetes risk independent of general obesity. However, no longitudinal studies have explored the extent to which total and regional FMRs may confer risks. We aimed to measure the sex-specific associations between FMRs of the arm, leg, trunk and whole body and incident type 2 diabetes.

METHODS

A total of 464 817 participants (207 286 men and 257 531 women, mean age 56.5 ± 8.2 and 56.2 ± 8.0 years old, respectively) free of diabetes at baseline were included in this prospective cohort study with UK Biobank data. Fat mass and muscle mass were estimated using a bioelectrical impedance assessment device (Tanita BC 418MA). FMR was calculated as fat mass divided by muscle mass in corresponding body parts (total body, arm, leg and trunk). Cox proportional hazard models were used to estimate the aforementioned associations among men and women. Interaction analyses were performed between FMRs and body mass index (BMI) categories (BMI < 25 kg/m² and BMI ≥ 25 kg/m² ).

RESULTS

Over the median 11.0 years (5 057 534 person-years) of follow-up, we documented 11 618 cases of type 2 diabetes. There was a significantly positive association between total and regional FMR and incident type 2 diabetes, even after adjusting for BMI and other covariates. Compared with other body parts, FMRs of the whole body and leg showed the strongest relationship among men and women, respectively (hazard ratio per 1 SD, 95% confidence interval: 1.67, 1.55-1.80; 1.45, 1.39-1.53). A significant interaction (P for interaction < 0.001) between BMI category and FMRs of different body parts was observed. In the stratified analysis by BMI category and tertiles of FMRs, overweight/obese individuals with a high FMR tertile tended to have the highest hazard ratio, ranging from 5.91 to 7.94 in whole body and regional areas.

CONCLUSIONS

In this large prospective study, higher total and regional FMRs were associated with a higher risk of developing type 2 diabetes, independent of BMI. This association was markedly strengthened in participants with BMI ≥ 25 kg/m² .

A Comparison of Supine Versus Stand-on Bioimpedance Devices to Assess Breast Cancer-Related Lymphedema

Background: While supine bioimpedance devices are used to evaluate for lymphedema (LE), stand-on devices are gaining popularity. Because research on differences in bioimpedance values between the two devices is limited, this study's purposes were to: (1) determine the average upper limb impedance values and inter-limb ratios for women who self-reported having (n = 34) or not having (n = 61) a history of LE, using a single-frequency supine device and a multifrequency stand-on device; (2) compare the level of agreement in inter-limb impedance ratios between the two devices; evaluate the percent agreement between the two devices in classifying cases of LE using established supine thresholds; and evaluate the percent agreement in classifying cases of LE between the supine device using previously established supine thresholds and the stand-on device using two published standing thresholds. Methods and Results: Bioimpedance measures were done using the two devices. For the entire sample, absolute impedance values for both the affected and unaffected limbs were significantly higher for the stand-on device in women with and without LE. Impedance values for the two methods were highly correlated. Bland-Altman analysis determined that for the entire range of impedance ratios the values for the two devices could not be used interchangeably. Conclusions: Findings suggest that the stand-on device can be a useful and valid tool to assess for LE. However, because agreement is not perfect, values obtained from the two devices should not be used interchangeably to evaluate for changes in impedance ratios, particularly for ratios of >1.20.