New reference values for body composition by bioelectrical impedance analysis in the general population: results from the UK Biobank

The efficacy of DASH combined with time-restricted feeding (16/8) on metabolic associated fatty liver disease management: a randomized controlled trial

Recent studies have utilized time-restricted feeding (16/8) (TRF) and dietary approaches to stop hypertension separately to manage metabolic-associated fatty liver disease (MAFLD); however, the effectiveness of combining these two approaches has not been investigated. The objective of this study was to examine the impact of TRF in conjunction with a DASH diet on various factors related to MAFLD. A 12-week randomized controlled trial was conducted to assess the impact of TRF (16/8), along with a DASH diet, compared with a control diet based on standard meal distribution, in patients with MAFLD. An investigation was conducted to examine alterations in anthropometric indices, as well as liver parameters, serum metabolic indices, and an inflammatory marker. The TRF plus DASH diet reduced body mass index (p = 0.03), abdominal circumference (p = 0.005), controlled attenuation parameter (CAP) (p < 0.001), alanine aminotransferase (p = 0.039), and aspartate aminotransferase (0.047) compared to the control group. The levels of insulin and homeostasis model assessment of insulin resistance reduced in both groups significantly (P < 0.05). In MAFLD patients, TRF (16/8) in combination with a DASH diet is superior to a low-calorie diet in promoting obesity indices, and hepatic steatosis and fibrosis. Further long-term investigations are needed to draw definitive conclusions.

Psychological-Emotional Aspect and Lifestyle in Professional Males Rugby Athletes

BACKGROUND

Recent research emphasizes the importance of integrating psychological-emotional factors with nutrition and body composition in athletes. This study investigates the correlations between these aspects in 36 professional rugby players, aiming to identify relationships that could optimize sports performance and overall well-being.

METHODS

The study sample included 36 male athletes (mean age: 24.4 ± 2.1 years, weight: 86.5 ± 7.1 kg, and height: 181.8 ± 5.7 cm). Four assessment tools were used: the Short Form Health Survey Questionnaire (SF-36) to evaluate quality of life, the Mediterranean diet adherence (MEDI-LITE), the International Physical Activity Questionnaire (IPAQ), and body composition measurements (stadiometer and BIVA). Statistical analyses, including the Shapiro-Wilk test, Pearson, and Spearman correlations, were conducted to explore relationships between the variables.

RESULTS

The athletes' mental and physical health was comparable to the general population (mean MCS = 50.5 ± 7.4, PCS = 49.6 ± 9.6). Mediterranean diet adherence was low (mean MEDI-LITE = 8.6 ± 2.6), while physical activity levels were high (mean IPAQ = 2560.5 ± 950.1). Body composition indicated overweight status (mean BMI = 26.15 ± 1.62 kg/m2, body fat = 22 ± 4.3%). Positive correlations were observed between mental health, diet adherence, and physical activity, with a stronger link between physical activity and body composition.

CONCLUSIONS

This study confirms a relationship between psychological-emotional factors, nutrition, and body composition in athletes, suggesting an integrated approach to optimize performance. However, causality remains unconfirmed, and the small sample size limits generalizability. Future research should include larger, more diverse samples to expand these findings.

Development and validation of reference equations for dual-energy X-ray absorptiometry-derived measures of fat-free mass in adults aged 45-85 years: results from the Canadian Longitudinal Study on Aging

Reference equations for fat-free mass (FFM) and lean soft tissue mass (LM) measures obtained from dual-energy X-ray absorptiometry (DEXA) are important for the interpretation of body composition. This study developed and validated reference equations for FFM and LM using DEXA from the Canadian Longitudinal Study on Aging. Reference equations were developed using data from a random population-based sample of ostensibly healthy and functionally independent adults aged 45-85 years. Reference equations for absolute (accounting for age, sex, height, and body mass) and height-adjusted aka index (accounting for age, sex, and body mass index) measures of FFM and LM were developed using quantile regression. Reference equations were respectively developed and validated in derivation (80%) and validation cohorts (20%). Reference equations were applied to symptomatic adults with self-reported chronic obstructive pulmonary disease (COPD) or heart disease to assess discriminant validity; and compared with other published equations to assess performance. Bland-Altman analyses and Lin's concordance correlation coefficients were utilised to assess agreement. Reference equations for 5th, 10th, 50th, 90th, and 95th percentiles were developed for DEXA-derived estimates of FFM and LM based on 1881 healthy participants (57% male) aged 55 [IQR: 50-61] years. Reference equations performed comparably in the validation cohort and discriminated reference values between ostensibly healthy adults and people with symptomatic COPD or heart disease. Previously published reference equations tended to over- or under-predict estimates of LM compared with the current reference equations. This study provides a comprehensive and validated set of reference equations for estimating and interpreting FFM and LM from DEXA in Canadian adults aged 45-85 years, although additional validation may be required for those >75 years.

Causal relationships between obesity-related anthropometric indicators and sepsis risk: a Mendelian-randomization study

Background

Previous studies have reported an association between obesity and risk of sepsis. However, the results have been inconsistent, and no causal inference can be drawn from them. Therefore, we conducted a Mendelian-randomization (MR) study to investigate causal relationships between available obesity-related anthropometric indicators and sepsis risk.

Methods

We performed MR analyses using genome-wide association study (GWAS) summary statistics on 14 anthropometric indicators [namely body mass index (BMI), waist and hip circumferences (WC, HC), basal metabolic rate (BMR), whole-body fat mass (WBFM), trunk fat mass (TFM), leg fat mass (LFM), arm fat mass (AFM), body fat percentage (BFP), whole-body fat-free mass (WBFFM), trunk fat-free mass (TFFM), leg fat-free mass (LFFM), arm fat-free mass (AFFM), and whole-body water mass (WBWM)], sepsis, critical care sepsis, and 28-day death due to sepsis from the UK Biobank and FinnGen cohort. The primary method of MR analysis was inverse variance-weighted average method. Sensitivity analyses, including heterogeneity and horizontal-pleiotropy tests, were conducted to assess the stability of the MR results. Additionally, we applied multiple-variable MR (MVMR) to evaluate the effect of BMI on the relationship between each anthropometric indicator and sepsis risk.

Results

Our MR analysis demonstrated causal relationships between 14 anthropometric indicators and sepsis of different severities. After we adjusted for BMI, MVMR analyses indicated that WC, BMR, LFM, WBFFM, TFFM, AFFM, and WBWM remained significantly associated with the presence of sepsis (all p < 0.05). A sensitivity analysis confirmed the reliability of our MR results, and no significant horizontal pleiotropy was detected.

Conclusion

This MR study revealed that increases in obesity-related anthropometric indicators had causal associations with a higher risk of sepsis, which might provide important insights for the identification of individuals at risk for sepsis in community and hospital settings.

The weight of weights: Causal impact of overweight on major depressive disorder and its disparate association with suicide attempts in over 450,000 individuals of European ancestry (AM-SRNMA 003)

AIM

Some studies and societal discussions have suggested a potential link between overweight and a higher risk of mental disorders and suicidal ideation. However, the causal relationships between these factors remain unclear. This study aims to assess the bidirectional causal associations between overweight and mental disorders, including suicidal attempts.

METHOD

We conducted a Two-Sample Mendelian Randomization study utilizing data from over 450,000 individuals of European ancestry sourced from a comprehensive Genome-Wide Association Study database. We chose single-nucleotide polymorphisms as instrumental variables.

RESULTS

Our analyses consistently supported a unidirectional causal association of overweight with the increased risk of major depressive disorder (MDD, β = 0.152, se = 0.069, P = 0.027), bipolar affective disorders (BD, β = 0.197, se = 0.092, P = 0.033), and attention-deficit / hyperactivity disorder (ADHD, β = 0.308, se = 0.080, P = 1.366 × 10-4). We observed no significant causal relationships for the exposure of overweight to anxiety disorder (AD), manic episode (MA), panic disorder (PD), schizophrenia (SZ), substance use disorder (SUD), autism spectrum disorder (ASD), ever attempted suicide, recent thoughts of suicide or self-harm, and suicide or other intentional self-harm events.

CONCLUSION

This study has provided evidence for the causal relationship between overweight and MDD, BD, ADHD, with no observed relationship between overweight and AD, MA, PD, SZ, SUD, ASD, ever attempted suicide, recent thoughts of suicide or self-harm, and suicide or other intentional self-harm events.

Adiposity, fat-free mass and incident heart failure in 500 000 individuals

BACKGROUND AND AIMS

The independent role of body fat distribution and fat-free mass in heart failure (HF) risk is unclear. We investigated the role of different body composition compartments in risk of HF.

METHODS

Present analyses include 428 087 participants (mean age 55.9 years, 44% male) from the UK Biobank. Associations of long-term average levels of body composition measures with incident HF were determined using adjusted Cox proportional hazards regression models.

RESULTS

Over a median follow-up of 13.8 years, there were 10 455 first-ever incident HF events. Overall, HF risk was more strongly associated with central adiposity (waist circumference (WC) adjusted for body mass index (BMI); HR 1.38, 95% CI 1.32 to 1.45) than general adiposity (BMI adjusted for WC; HR 1.22, 95% CI 1.16 to 1.27). Although dual X-ray absorptiometry-derived body fat remained positively related to HF after adjustment for fat-free mass (HR 1.37, 95% CI 1.18 to 1.59), the association of fat-free mass with HF was substantially attenuated by fat mass (HR 1.12, 95% CI 1.01 to 1.26) while visceral fat (VAT) remained associated with HF independent of subcutaneous fat (HR 1.20, 95% CI 1.09 to 1.33). In analyses of HF subtypes, HF with preserved ejection fraction was independently associated with all fat measures (eg, VAT: HR 1.23, 95% CI 1.12 to 1.35; body fat: HR 1.36, 95% CI 1.17 to 1.57) while HF with reduced ejection fraction was not independently associated with fat measures (eg, VAT: HR 1.29, 95% CI 0.98 to 1.68; body fat: HR 1.29, 95% CI 0.80 to 2.07).

CONCLUSIONS

This large-scale study shows that excess adiposity and fat mass are associated with higher HF risk while the association of fat-free mass with HF could be explained largely by its correlation with fat mass. The study also describes the independent relevance of body fat distribution to HF subtypes, suggesting different mechanisms may be driving their aetiopathogenesis.

Normative values for body composition in 22,191 healthy Norwegian adults 20-99 years: The HUNT4 study

BACKGROUND

Body mass, body mass index (BMI), and body composition components are essential for health and longevity. Considering the influence of demographic factors on body composition, there is a need for tailored reference values based on age-, sex-, and geography. We aimed to construct a comprehensive reference material on body composition in healthy Norwegian adults.

METHODS

In this cross-sectional study, we estimated age- and sex-specific reference values for body-, fat-, and muscle mass variables using multi-frequency bioelectrial impedance analysis (such as body fat percentage, skeletal muscle mass and visceral fat area) in 22,191 healthy adults aged 20-99 years participating in the Trøndelag Health Study 4 (HUNT4). We calculated the fat mass and skeletal muscle mass index as the total fat and muscle mass relative to height squared and used general linear models to explore the associations between physical activity (PA), BMI, and age.

RESULTS

With a BMI (kg/m2) of 25.4 (SD 5.1) and 26.0 (4.5) for women and men, respectively, the youngest age group (20-39 yrs) had a lower BMI compared to their counterparts aged 40-59 years (26.3 [4.5] and 27.5 [3.8]) and ≥ 60 years (25.7 [4.1] and 26.5 [3.4]), respectively. Those aged 20-39 years also had the lowest values for the different body fat variables measured. Fat mass index (kg/m2) was 8.41 (4.00) and 5.81 (3.29) for women and men aged 20-39 years, respectively, compared to 9.25 (3.21) and 6.86 (2.46) for those aged ≥60 years. The oldest age group had the lowest values for the various muscle mass variables; women and men aged 60+ years had a skeletal muscle mass index (kg/m2) of 8.91 (0.85) and 10.96 (1.00), respectively. Corresponding values for those aged 20-39 years were 9.33 (0.97) and 11.49 (1.15). For all age groups and both sexes, regular physical activity was associated with lower levels of fat mass, whereas the association between muscle mass and PAwas less conclusive. When using body fat percentage as an obesity measure, we observed a much higher obesity prevalence (41.2%) in the study population compared to BMI (17.3%).

CONCLUSIONS

Our study offers a comprehensive reference for body composition among healthy adults in Norway, aiding the identification of abnormal fat and muscle mass values across age groups. We also highlight that BMI often misclassifies individuals with adiposity levels in the overweight or obese category as lean. Therefore, incorporating body composition when defining obesity could enable early intervention to prevent cardiometabolic diseases.

Dietary Inflammatory Index and Dietary Diversity Score Associated with Sarcopenia and Its Components: Findings from a Nationwide Cross-Sectional Study

Little is known about the independent and joint effects of the energy-adjusted dietary inflammatory index (E-DII) and dietary diversity score (DDS) on sarcopenia and its components (low muscle mass, low muscle strength, and low physical performance). A total of 155,669 UK Biobank participants with ≥1 (maximum 5) 24 h dietary assessments were included in this cross-sectional analysis. We used logistic regression models to investigate the associations of E-DII and DDS with sarcopenia and its three components. We further examined the joint effects of E-DII and DDS on sarcopenia and its components using additive and multiplicative interaction analyses. We observed that lower E-DII and higher DDS were associated with lower odds of sarcopenia and its components. There were significant joint associations of E-DII and DDS with sarcopenia and low physical performance (p-interaction < 0.05) on the multiplicative interactive scale. Our study suggests that lower dietary inflammatory potential and higher dietary diversity might be important protective factors against sarcopenia and its components. More cases of sarcopenia and low physical performance might be preventable by adherence to a more anti-inflammatory diet combined with a higher dietary diversity.

Agreement between bioimpedance analysis and ultrasound scanning in body composition assessment

OBJECTIVES

This study aimed at evaluating the agreement between bioelectrical impedance analysis (BIA) using ABC-02 Medas and A-mode ultrasound (AUS) using BodyMetrix™ BX2000 for fat mass (FM), fat free mass (FFM), and body fat percentage (%BF) in females.

METHODS

The cross-sectional, single-center, observational study was performed in 206 female subjects aged 18-67 years. The examination program included measurements of body height and weight along with waist, hip circumferences, and body composition analysis. The measurements were performed by ultrasound scanner and bioimpedance analyzer.

RESULTS

We found that 20.9% of women were obese based on BMI (≥30 kg/m2), which was significantly lower when using a criterion based on body fat percentage (%BF ≥ 30%) measured with US (53.4%, p = .0056) or BIA (54.8%, p = .0051). At the group level, both methods were found interchangeable and showed practically negligible differences (0.1% for %BF, 0.5 kg for FM, and 0.4 kg for FFM). Agreement analysis conducted in the whole sample revealed a low level of agreement in estimating %BF (CCC = 0.72 0.77 0.82) and FFM (CCC = 0.81 0.84 0.86), and medium level of agreement in estimating FM (CCC = 0.91 0.93 0.94). The level of agreement in estimating %BF and FFM was improved to the medium level with the use of newly generated prediction equations.

CONCLUSION

Thus, the proposed equations can be used for conversion of body composition results obtained by AUS into the BIA data.

Age- and sex-specific normative values for muscle mass parameters in 18,625 Brazilian adults

Background

The present study aimed to provide age- and sex-specific normative values for muscle mass parameters in Brazilian adults.

Methods

Data pertaining to Brazilian adults (18+ years) who attended a nutritional clinical between January 2018 and July 2022 were analyzed. Muscle mass parameters were assessed using a bioimpedance digital scale (InBody 230, GBC BioMed NZ). Assessments were conducted under standard conditions, with participants refraining from physical exercise for 96 h and from eating or drinking (including water) for 8 h before evaluations.

Results

A total of 18,625 Brazilian adults were analyzed. Normative values for absolute and relative (height, m2) muscle mass and appendicular muscle mass (ASM) were calculated. In addition, specific age-related changes in muscle mass parameters were observed. In women, muscle mass peaked between the ages of 40-49 before gradually declining at an average rate of 5.7% per decade from the sixth decade of life onwards. ASM reached its peak earlier, during the third decade of life, and started to decline later, from 50 to 59 years. In contrast, absolute and ASM peaked at 40-49 years and declined from the sixth decade of life in men. Both sexes displayed a slightly greater decline in ASM than in muscle mass (13 vs. 12%).

Conclusions

The present study provides normative values for absolute and relative muscle mass and ASM in Brazilian adults. Furthermore, important specific age-related changes in muscle mass parameters were observed. These data have public health implications and might serve as a reference tool to guide health professionals.

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.

Feasibility of a Novel Geriatric Rehabilitation Program for People With COPD-induced Malnutrition and Muscle Wasting: A Qualitative Study

Background and Purpose: Patients with COPD-induced malnutrition and muscle wasting are often frail. Consequently, traditional rehabilitation may be even counterproductive due to energy costs and there is a need for specialized rehabilitation programs, which are lacking for these patients. We developed such a program, which includes resistance training, following Nonlinear Periodized Exercise principles and physical energy management, in combination with a restriction of physical activities. The purpose of the study was to investigate the feasibility and the potential effects of this program. Methods: Patients who are eligible for the program are those with COPD gold III/IV and a fat free mass index below standard. We conducted a qualitative feasibility study and interviewed both patients and healthcare professionals (HCPs), using a deductive approach. The open interviews were qualitatively analyzed focussing on six areas of Bowens' feasibility model: acceptability, demand, implementation, practicality, limited efficacy, and integration. Results and discussions: Seven patients and seven HCPs were interviewed. For patients, key factors that helped to adhere to the program were knowledge about energy management, alternative skills to cope with COPD, and social support. They found the program beneficial. However, several patients considered a limitation of walking and ADL activities challenging. HCPs considered the program feasible and beneficial especially for those patients who accept they need a behavior change and who adhere to the program. For HCPs, key factors were the consistent approach and coaching skills of the multidisciplinary team members, and the monitoring role of the nurses. The limitation of physical activity and endurance training deviates from existing geriatric rehabilitation programs which propagate functional activity and training. Still, evidence from the current study suggests that our tailored approach for these patients might be more appropriate and also potentially effective without harm for physical function. Conclusions: Our novel, multidisciplinary rehabilitation program is considered feasible and clinically relevant by both patients and healthcare professionals. The next step is to explore its effects on muscle strength, physical functioning, and quality of life.

Combined Exercise Training and Nutritional Interventions or Pharmacological Treatments to Improve Exercise Capacity and Body Composition in Chronic Obstructive Pulmonary Disease: A Narrative Review

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease that is associated with significant morbidity, mortality, and healthcare costs. The burden of respiratory symptoms and airflow limitation can translate to reduced physical activity, in turn contributing to poor exercise capacity, muscle dysfunction, and body composition abnormalities. These extrapulmonary features of the disease are targeted during pulmonary rehabilitation, which provides patients with tailored therapies to improve the physical and emotional status. Patients with COPD can be divided into metabolic phenotypes, including cachectic, sarcopenic, normal weight, obese, and sarcopenic with hidden obesity. To date, there have been many studies performed investigating the individual effects of exercise training programs as well as nutritional and pharmacological treatments to improve exercise capacity and body composition in patients with COPD. However, little research is available investigating the combined effect of exercise training with nutritional or pharmacological treatments on these outcomes. Therefore, this review focuses on exploring the potential additional beneficial effects of combinations of exercise training and nutritional or pharmacological treatments to target exercise capacity and body composition in patients with COPD with different metabolic phenotypes.

Appendicular Muscle Mass Index was Stronger than Body Mass Index in Association with Atherosclerosis in the Community-Dwelling Elderly

AIMS

Low muscle mass is associated with advanced atherosclerosis. However, only very few studies on the elderly have investigated a dose-response relationship between muscle mass and atherosclerosis. Furthermore, whether the relationship between muscle mass and atherosclerosis is stronger than that between body mass index (BMI) and atherosclerosis among the elderly population remains to be determined.

METHODS

A community-based sample of apparently healthy elderlies (≥ 65 years) was cross-sectionally examined for the association between appendicular skeletal muscle mass (ASM) and brachial-ankle pulse wave velocity (baPWV), a measure of atherosclerosis. We categorized the participants according to sex-specific quintiles of the ASM index (ASM/height2) or BMI. Using multivariable linear regression, we compared the slope of one standard deviation higher ASM index for baPWV with the corresponding slope of BMI, separately (single-index model) and jointly (simltaneously-adjusted model).

RESULTS

The ASM index and BMI of a total of 995 participants (60.0% women, mean age 73 years) were significantly inversely associated with baPWV in a dose-response manner across the quintiles in both sexes. The slope for the ASM index tended to be greater than that for BMI in the single-index and simultaneously-adjusted models in both sexes after adjusting for confounders.

CONCLUSIONS

Among a community-dwelling elderly population, the association between ASM and baPWV was stronger than, and independent of that between BMI and baPWV. These findings suggest that ASM provides more important information on atherosclerosis in the elderly than BMI does.

Differential impacts between fat mass index and fat-free mass index on patients with COPD

BACKGROUND

Differences in the clinical impacts of fat mass index (FMI) and fat-free mass index (FFMI) remain unclear in patients with chronic obstructive pulmonary disease (COPD). We hypothesized that FMI and FFMI have different impacts on 1) emphysema and 2) pulmonary function and health-related quality of life of COPD patients.

METHODS

Patients with COPD (n = 228), enrolled in a multicenter prospective 3-year cohort were classified into four groups based on baseline median FMI and FFMI values. Emphysema assessed as the ratio of low attenuation area to total lung volume (LAA%) on computed tomography, pulmonary function, and health-related quality of life assessed using the St. George's Respiratory Questionnaire (SGRQ) were compared.

RESULTS

The four groups had statistically significant differences in LAA%, pulmonary function, and SGRQ scores. The Low FMI Low FFMI group exhibited the highest LAA%, lowest pulmonary function, and worst SGRQ scores among the four groups. In addition, these differences were consistent over 3 years. Multivariate analysis showed that low FMI was associated with high LAA%, low inspiratory capacity/total lung capacity (IC/TLC), and carbon monoxide transfer coefficient (KCO). In contrast, low FFMI was associated with these factors as well as worse SGRQ scores.

CONCLUSION

FMI and FFMI have different effects on the clinical manifestations of COPD. Both low fat and muscle mass contributed to severe emphysema, whereas only low muscle mass contributed to worse health-related quality of life in patients with COPD.

Analysis of Serious Weight Gain in Patients Using Alectinib for ALK-Positive Lung Cancer

INTRODUCTION

Alectinib is a standard-of-care treatment for metastatic ALK+ NSCLC. Weight gain is an unexplored side effect reported in approximately 10%. To prevent or intervene alectinib-induced weight gain, more insight in its extent and etiology is needed.

METHODS

Change in body composition was analyzed in a prospective series of 46 patients with ALK+ NSCLC, treated with alectinib. Waist circumference, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and skeletal muscle were quantified using sliceOmatic software on computed tomography images at baseline, 3 months (3M), and 1 year (1Y). To investigate an exposure-toxicity relationship, alectinib plasma concentrations were quantified. Four patients with more than 10 kg weight gain were referred to Erasmus MC Obesity Center CGG for in-depth analysis (e.g., assessments of appetite, dietary habits, other lifestyle, medical and psychosocial factors, and extensive metabolic and endocrine assessments, including resting energy expenditure).

RESULTS

Mean increase in waist circumference was 9 cm (9.7%, p < 0.001) in 1Y with a 40% increase in abdominal obesity (p = 0.014). VAT increased to 10.8 cm2 (15.0%, p = 0.003) in 3M and 35.7 cm2 (39.0%, p < 0.001) in 1Y. SAT increased to 18.8 cm2 (12.4%, p < 0.001) in 3M and 45.4 cm2 (33.3%, p < 0.001) in 1Y. The incidence of sarcopenic obesity increased from 23.7% to 47.4% during 1Y of treatment. Baseline waist circumference was a positive predictor of increase in VAT (p = 0.037). No exposure-toxicity relationship was found. In-depth analysis (n = 4) revealed increased appetite in two patients and metabolic syndrome in all four patients.

CONCLUSIONS

Alectinib may cause relevant increased sarcopenic abdominal obesity, with increases of both VAT and SAT, quickly after initiation. This may lead to many serious metabolic, physical, and mental disturbances in long-surviving patients.

Multiple anthropometric measures and proarrhythmic 12-lead ECG indices: A mendelian randomization study

BACKGROUND

Observational studies suggest that electrocardiogram (ECG) indices might be influenced by obesity and other anthropometric measures, though it is difficult to infer causal relationships based on observational data due to risk of residual confounding. We utilized mendelian randomization (MR) to explore causal relevance of multiple anthropometric measures on P-wave duration (PWD), PR interval, QRS duration, and corrected QT interval (QTc).

METHODS AND FINDINGS

Uncorrelated (r2 < 0.001) genome-wide significant (p < 5 × 10-8) single nucleotide polymorphisms (SNPs) were extracted from genome-wide association studies (GWAS) on body mass index (BMI, n = 806,834), waist:hip ratio adjusted for BMI (aWHR, n = 697,734), height (n = 709,594), weight (n = 360,116), fat mass (n = 354,224), and fat-free mass (n = 354,808). Genetic association estimates for the outcomes were extracted from GWAS on PR interval and QRS duration (n = 180,574), PWD (n = 44,456), and QTc (n = 84,630). Data source GWAS studies were performed between 2018 and 2022 in predominantly European ancestry individuals. Inverse-variance weighted MR was used for primary analysis; weighted median MR and MR-Egger were used as sensitivity analyses. Higher genetically predicted BMI was associated with longer PWD (β 5.58; 95%CI [3.66,7.50]; p = < 0.001), as was higher fat mass (β 6.62; 95%CI [4.63,8.62]; p < 0.001), fat-free mass (β 9.16; 95%CI [6.85,11.47]; p < 0.001) height (β 4.23; 95%CI [3.16, 5.31]; p < 0.001), and weight (β 8.08; 95%CI [6.19,9.96]; p < 0.001). Finally, genetically predicted BMI was associated with longer QTc (β 3.53; 95%CI [2.63,4.43]; p < 0.001), driven by both fat mass (β 3.65; 95%CI [2.73,4.57]; p < 0.001) and fat-free mass (β 2.08; 95%CI [0.85,3.31]; p = 0.001). Additionally, genetically predicted height (β 0.98; 95%CI [0.46,1.50]; p < 0.001), weight (β 3.45; 95%CI [2.54,4.36]; p < 0.001), and aWHR (β 1.92; 95%CI [0.87,2.97]; p = < 0.001) were all associated with longer QTc. The key limitation is that due to insufficient power, we were not able to explore whether a single anthropometric measure is the primary driver of the associations observed.

CONCLUSIONS

The results of this study support a causal role of BMI on multiple ECG indices that have previously been associated with atrial and ventricular arrhythmic risk. Importantly, the results identify a role of both fat mass, fat-free mass, and height in this association.

Differential Impact of Low Fat-Free Mass in People With COPD Based on BMI Classifications: Results From the COPD and Systemic Consequences-Comorbidities Network

BACKGROUND

Alterations in body composition, including a low fat-free mass index (FFMI), are common in patients with COPD and occur regardless of body weight.

RESEARCH QUESTION

Is the impact of low FFMI on exercise capacity, health-related quality of life (HRQL), and systemic inflammation different among patients with COPD stratified in different BMI classifications?

STUDY DESIGN AND METHODS

We analyzed baseline data of patients with COPD from the COPD and Systemic Consequences-Comorbidities Network cohort. Assessments included lung function, bioelectrical impedance analysis, 6-min walk distance (6MWD), HRQL, and inflammatory markers. Patients were stratified in underweight, normal weight (NW), preobese, and obese according to BMI and as presenting low, normal, or high FFMI using 25th and 75th percentiles of reference values. Linear mixed models were used to investigate the associations between fat-free mass (FFM) and fat mass with secondary outcomes in each BMI group.

RESULTS

Two thousand one hundred thirty-seven patients with COPD (Global Initiative for Chronic Obstructive Lung Disease stages 1-4; 61% men; mean ± SD age, 65 ± 8 years; mean ± SD FEV₁, 52.5 ± 18.8% predicted) were included. The proportions of patients in underweight, NW, preobese, and obese groups were 12.3%, 31.3%, 39.6%, and 16.8%, respectively. The frequency of low FFMI decreased from lower to higher BMI groups (underweight, 81%; NW, 53%; preobese, 42%; and obese, 39%). FFM was associated with the 6MWD in the underweight group, even when adjusting for a broad set of covariates (P < .05). HRQL was not associated with FFM after adjustment for lung function or dyspnea (P > .32). Fat mass was associated with higher systemic inflammation in the NW and preobese groups (P < .05).

INTERPRETATION

In patients with COPD with lower weight, such as underweight patients, higher FFMI is associated independently with better exercise capacity. In contrast, in preobese and obese patients with COPD, a higher FFMI was not consistently associated with better outcomes.

Fat-Free Mass Index as a Surrogate Marker of Appendicular Skeletal Muscle Mass Index for Low Muscle Mass Screening in Sarcopenia

OBJECTIVES

We aimed to examine the relationship between the fat-free mass index (FFMI; FFM/height²) and appendicular skeletal muscle mass index (ASMI; ASM/height²), measured using both bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA), and investigate the effects of age and obesity. We also evaluated the suitability of BIA-measured FFMI as a simple surrogate marker of the ASMI and calculated the optimal FFMI cutoff value for low muscle mass screening to diagnose sarcopenia.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

This study included 1313 adults (women, 33.6%) aged 40-87 years (mean age, 55 ± 10 years) from the WASEDA'S Health Study.

METHODS

Body composition was measured using multifrequency BIA and DXA. Low muscle mass was defined according to the criteria of the Asian Working Group for Sarcopenia 2019.

RESULTS

BIA-measured FFMI showed strong positive correlations with both BIA- (r = 0.96) and DXA-measured (r = 0.95) ASMIs. Similarly, in the subgroup analysis according to age and obesity, the FFMI was correlated with the ASMI. The areas under the receiver operating characteristic curve for screening low muscle mass defined by DXA-measured ASMI using BIA-measured FFMI values were 0.95 (95% CI 0.93-0.97) for men and 0.91 (95% CI 0.87-0.94) for women. The optimal BIA-measured FFMI cutoff values for screening low muscle mass defined by DXA-measured ASMI were 17.5 kg/m² (sensitivity 89%, specificity 88%) for men and 14.6 kg/m² (sensitivity 80%, specificity 86%) for women.

CONCLUSIONS AND IMPLICATIONS

The FFMI showed a strong positive correlation with BIA- and DXA-measured ASMIs, regardless of age and obesity. The FFMI could be a useful simple surrogate marker of the ASMI for low muscle mass screening in sarcopenia in community settings. The suggested FFMI cutoff values for predicting low muscle mass are <18 kg/m² in men and <15 kg/m² in women.

Studies on human body composition in Russia: past and present

Despite the presence of body composition studies in Russia, there are no current reviews on this topic, and the results are relatively rarely published abroad. Our aim was to describe the history and current state of this research work, to list unresolved problems, and to outline possible developmental trends. For completeness, in the initial part of the review, traditional research areas indirectly related to body composition studies are considered, namely, the analysis of biological variation of anthropometric parameters and somatotyping.

It can be seen that anthropometry and bioimpedance analysis (BIA) are mainly used to assess body composition in Russia. Other methods, such as double-energy X-ray absorptiometry (DXA), are utilized less often. The achievements include the common use of comprehensive anthropometry in anthropological studies, some advancements in clinical studies, approbation of potentially important methods such as the deuterium dilution method and three-dimensional laser-based photonic scanning, and ongoing mass population BIA measurements in health centers. Various bioimpedance instruments are manufactured, the local reference BIA body composition data are available, and a large updated BIA database is ready for international comparisons.

Among major limitations of body composition research in Russia, one can note the lack of validation studies using reference methods, so that foreign regression formulas are used with the double indirect methods, such as anthropometry and BIA, despite the fact that their accuracy has not yet been checked in our population. Conventional reference body composition assessment methods, such as three- or four-component molecular-level models and whole-body in vivo neutron activation analysis, were not applied yet, despite the technical feasibility.

In general, it can be argued that the body composition research in Russia follows the observed global trends. Along with the achievements, there are a number of unresolved methodological and organizational issues. Prospects for further research include validation studies, updating reference population body composition data, and establishing local cut-offs for malnutrition and disease risks. In our view, further development could be facilitated with the establishment of well-equipped Human Body Composition Units in major Russian research centers, such as Moscow State University, which could be assigned a coordinating and methodical role.

Is ambient air pollution associated with sarcopenia? Results from a nation-wide cross-sectional study

BACKGROUND

sarcopenia is a disease that involves the degeneration of muscle strength, muscle mass and physical performance. It remains unknown whether air pollution exposure increases the risk of sarcopenia.

METHODS

the baseline survey of the UK Biobank was used in this study. Sarcopenia was identified according to European Working Group on Sarcopenia in Older People 2 (EWGSOP2) and classified into non-sarcopenia and probable sarcopenia. Land use regressions were used to estimate concentrations of particulate matter (PM2.5), coarse particles (PMcoarse), PM10, PM2.5 absorbance, nitrogen dioxide (NO2) and nitrogen oxides (NOx). Logistic regression models were applied to estimate the associations between air pollution and sarcopenia and its components.

RESULTS

out of 352,265 participants, 28,710 (8.2%) were identified with probable sarcopenia. In adjusted models, there were increased odds of probable sarcopenia for each interquartile range increase in PM2.5 (OR: 1.06; 95% CI: 1.04, 1.07), PM10 (OR: 1.15; 95% CI: 1.13, 1.17), PMcoarse (OR: 1.02; 95% CI:1.01, 1.03), PM2.5 absorbance (OR: 1.08; 95% CI: 1.07, 1.10), NO2 (OR: 1.12; 95% CI:1.10, 1.14) and NOx (OR: 1.06; 95% CI: 1.05, 1.08).

CONCLUSIONS

this study suggests that exposure to ambient air pollution might be one risk factor of sarcopenia. Prospective studies are needed to further confirm our findings.

Longitudinal Analysis of Quadriceps Muscle Strength in Patients with Previous COVID-19 Hospitalization and in Patients with Post-Acute Sequelae following Mild COVID-19

Muscle weakness is a prominent symptom in post-acute sequelae of COVID-19 (PASC). However, few studies have objectively and longitudinally assessed muscle strength after varying COVID-19 severity grades. This observational study aimed to explore the prevalence, determinants, and 1.5 years change of quadriceps muscle weakness in 98 patients discharged from COVID-19 hospitalization and in 50 patients with PASC following mild COVID-19. Isometric quadriceps maximal voluntary contraction (MVC) was assessed on a computerized dynamometer at three visits. Also, in a subgroup of 14 post-COVID-19 patients with quadriceps muscle weakness, muscle thickness and echo intensity were determined by muscle ultrasound of nine upper and lower extremity muscles. Muscle weakness was found in 59% of post-hospitalized patients and in 65% of those with PASC following mild COVID-19 at ~14 weeks after acute COVID-19. Whereas during ~1.5 years follow-up MVC modestly improved, muscle weakness prevalence remained unchanged. Hospital length of stay and diabetes mellitus were identified as possible predictors of muscle weakness following COVID-19 hospitalization. No predictors could be identified in those with PASC following mild COVID-19. Ultrasound outcomes revealed no large structural abnormalities. In conclusion, clinically relevant muscle weakness is common after COVID-19 and its long-term improvement is poor. Future studies with relevant control groups are warranted to confirm our data.

Energy expenditure and intake in COPD: The extent of unnoticed unbalance by predicting REE

Undernourishment is promoted by an unbalance between energy expenditure and intake. Resting energy expenditure (REE) in chronic obstructive pulmonary disease (COPD) is commonly predicted using the Harris-Benedict (HB) and the Angelillo-Moore (AM) formulas, however no study has investigated to which extent COPD patients with an energy unbalance go unnoticed when REE is predicted rather than measured with indirect calorimetry. This study demonstrates that 66% and 25% of negatively unbalanced patients go unnoticed when using HB and AM, respectively, urging to discourage the use of REE predicting formulas in clinical practice, at least in cases at risk of undernourishment.

The Association between Fat-Free Mass and Exercise Test Outcomes in People with Chronic Obstructive Pulmonary Disease: A Systematic Review

People with chronic obstructive pulmonary disease (COPD) tend to have abnormally low levels of fat-free mass (FFM), which includes skeletal muscle mass as a central component. The purpose of this systematic review was to synthesise available evidence on the association between FFM and exercise test outcomes in COPD. MEDLINE, Cochrane Library, EMBASE, Web of Science, and Scopus were searched. Studies that evaluated exercise-related outcomes in relation to measures of FFM in COPD were included. Eighty-three studies, containing 18,770 (39% female) COPD participants, were included. Considerable heterogeneity was identified in the ways that FFM and exercise test outcomes were assessed; however, higher levels of FFM were generally associated with greater peak exercise capacity. This association was stronger for some exercise test outcomes (e.g. peak rate of oxygen consumption during incremental cycle exercise testing) than others (e.g. six-minute walking distance). This review identified heterogeneity in the methods used for measuring FFM and exercise capacity. There was, in general, a positive association between FFM and exercise capacity in COPD. There was also an identified lack of studies investigating associations between FFM and temporal physiological and perceptual responses to exercise. This review highlights the significance of FFM as a determinant of exercise capacity in COPD.

Effect of perindopril or leucine on physical performance in older people with sarcopenia: the LACE randomized controlled trial

BACKGROUND

This trial aimed to determine the efficacy of leucine and/or perindopril in improving physical function in older people with sarcopenia.

METHODS

Placebo-controlled, parallel group, double-blind, randomized two-by-two factorial trial. We recruited adults aged ≥ 70 years with sarcopenia, defined as low gait speed (<0.8 m/s on 4 m walk) and/or low handgrip strength (women < 20 kg, men < 30 kg) plus low muscle mass (using sex and body mass index category-specific thresholds derived from normative UK BioBank data) from 14 UK centres. Eligible participants were randomized to perindopril 4 mg or placebo, and to oral leucine powder 2.5 g or placebo thrice daily. The primary outcome was the between-group difference in the short physical performance battery (SPPB) score over 12-month follow-up by repeated-measures mixed models. Results were combined with existing systematic reviews using random-effects meta-analysis to derive summary estimates of treatment efficacy.

RESULTS

We screened 320 people and randomized 145 participants compared with an original target of 440 participants. For perindopril [n = 73, mean age 79 (SD 6), female sex 39 (53%), mean SPPB 7.1 (SD 2.3)] versus no perindopril [n = 72, mean age 79 (SD 6), female sex 39 (54%), mean SPPB 6.9 (SD 2.4)], median adherence to perindopril was lower (76% vs. 96%; P < 0.001). Perindopril did not improve the primary outcome [adjusted treatment effect -0.1 points (95%CI -1.2 to 1.0), P = 0.89]. No significant treatment benefit was seen for any secondary outcome including muscle mass [adjusted treatment effect -0.4 kg (95%CI -1.1 to 0.3), P = 0.27]. More adverse events occurred in the perindopril group (218 vs. 165), but falls rates were similar. For leucine [n = 72, mean age 78 (SD 6), female sex 38 (53%), mean SPPB 7.0 (SD 2.1)] versus no leucine [n = 72, mean age 79 (SD 6), female sex 40 (55%), mean SPPB 7.0 (SD 2.5)], median adherence was the same in both groups (76% vs. 76%; P = 0.99). Leucine did not improve the primary outcome [adjusted treatment effect 0.1 point (95%CI -1.0 to 1.1), P = 0.90]. No significant treatment benefit was seen for any secondary outcome including muscle mass [adjusted treatment effect -0.3 kg (95%CI -1.0 to 0.4), P = 0.47]. Meta-analysis of angiotensin converting enzyme inhibitor/angiotensin receptor blocker trials showed no clinically important treatment effect for the SPPB [between-group difference -0.1 points (95%CI -0.4 to 0.2)].

CONCLUSIONS

Neither perindopril nor leucine improved physical performance or muscle mass in this trial; meta-analysis did not find evidence of efficacy of either ACE inhibitors or leucine as treatments to improve physical performance.

The Russian Bioimpedance Database: An Update

Extensive bioelectrical impedance analysis (BIA) data have the potential of health monitoring and the assessment of health risks at the population level. The importance of BIA data lies in their availability and abundance for many countries. In Russia, mass BIA data are generated by the national network of health centers (HCs). Our aim was to describe the structure and capabilities of the updated HCs' BIA database. Upon several requests between 2012 and 2020, 369 HCs representing all Federal districts of Russia and 60 out of 85 Federal subjects in them, submitted raw bioimpedance data which were obtained using the same type of BIA instrument, namely ABC-01 'Medas' (SRC Medas, Russia). After application of strict selection criteria, 2,429,977 BIA measurement records were selected that formed the updated 2010-2019 HCs' database. Various slices of the BIA data are described according to spatiotemporal, demographic and other characteristics. Reference curves of the bioimpedance phase angle according to age and sex are presented. Limitations and prospects for further work are outlined. We believe that, after appropriate sampling, the database can be utilized to study biological, geographical, social and other associations of the bioimpedance and body composition parameters, for generating updated national references, international comparisons and data standardization.

Reference percentiles for bioimpedance body composition parameters of healthy individuals: A cross-sectional study

OBJECTIVES

The aim of this study was to estimate the percentage distribution of body composition parameters for healthy people at different ages from the assessment of electrical bioimpedance.

METHODS

A cross-sectional study of healthy Brazilian aged 5 years and older. Were evaluated: total body fat; percent body fat; fat-free mass; percent lean mass; fat mass index; and fat-free mass index.

RESULTS

Of 1240 participants, with a median age of 27.0 years, 52.5% were female, and 73.7% were Caucasian. Most of the body composition variables were associated with age. The fat-free mass increased from youth to adult and decreased in the elderly in both sexes, with higher values in males than in females. In males, the percentage of lean mass has higher values in adolescence compared to childhood, and in adults compared to the elderly, when analyzed from the 50^th percentile. In women, fat-free mass compared to adulthood, values were higher in childhood and lower in older ages.

CONCLUSIONS

The study is the first to describe the Brazilian reference values for most clinical parameters of bioimpedance in percentiles stratified by different life cycles and sex. These findings can be very useful in clinical practice for health promotion and monitoring the nutritional status of the individual.

Nutritional Status and Body Composition in Patients Suffering From Chronic Respiratory Diseases and Its Correlation With Pulmonary Rehabilitation

As part of an individualized intervention to improve the physical, emotional, and social functioning of patients with chronic respiratory diseases in general and chronic obstructive pulmonary disease in particular, awareness of the presence and consequences of changes in body composition increased enormously during the last decades, and nutritional intervention is considered as an essential component in the comprehensive approach of these patients. This review describes the prevalence and the clinical impact of body composition changes and also provides an update of current intervention strategies. It is argued that body composition, preferentially a three-component evaluation of fat, lean, and bone mass, must become part of a thorough assessment of every patient, admitted for pulmonary rehabilitation.

Oxytocin-pathway polygenic scores for severe mental disorders and metabolic phenotypes in the UK Biobank

Oxytocin is a neuromodulator and hormone that is typically associated with social cognition and behavior. In light of its purported effects on social cognition and behavior, research has investigated its potential as a treatment for psychiatric illnesses characterized by social dysfunction, such as schizophrenia and bipolar disorder. While the results of these trials have been mixed, more recent evidence suggests that the oxytocin system is also linked with cardiometabolic conditions for which individuals with severe mental disorders are at a higher risk for developing. To investigate whether the oxytocin system has a pleiotropic effect on the etiology of severe mental illness and cardiometabolic conditions, we explored oxytocin's role in the shared genetic liability of schizophrenia, bipolar disorder, type-2 diabetes, and several phenotypes linked with cardiovascular disease and type 2 diabetes risk using a polygenic pathway-specific approach. Analysis of a large sample with about 480,000 individuals (UK Biobank) revealed statistically significant associations across the range of phenotypes analyzed. By comparing these effects to those of polygenic scores calculated from 100 random gene sets, we also demonstrated the specificity of many of these significant results. Altogether, our results suggest that the shared effect of oxytocin-system dysfunction could help partially explain the co-occurrence of social and cardiometabolic dysfunction in severe mental illnesses.

Evaluation of the Relationships between Simple Anthropometric Measures and Bioelectrical Impedance Assessment Variables with Multivariate Linear Regression Models to Estimate Body Composition and Fat Distribution in Adults: Preliminary Results

BACKGROUND

Overweight and obesity are conditions associated with sedentary lifestyle and accumulation of abdominal fat, determining increased mortality, favoring chronic diseases, and increasing cardiovascular risk. Although the evaluation of body composition and fat distribution are highly relevant, the high cost of the gold standard techniques limits their wide utilization. Therefore, the aim of this work was to explore the relationships between simple anthropometric measures and BIA variables using multivariate linear regression models to estimate body composition and fat distribution in adults.

METHODS

In this cross-sectional study, sixty-eight adult individuals (20 males and 48 females) were subjected to bioelectrical impedance analysis (BIA), anthropometric measurements (waist circumference (WC), neck circumference (NC), mid-arm circumference (MAC)), allowing the calculation of conicity index (C-index), fat mass/fat-free mass (FM/FFM) ratios, body mass index (BMI) and body shape index (ABSI). Statistical analyzes were performed with the R program. Nonparametric Statistical tests were applied to compare the characteristics of participants of the groups (normal weight, overweight and obese). For qualitative variables, the Fisher's exact test was applied, and for quantitative variables, the paired Wilcoxon signed-rank test. To evaluate the linear association between each pair of variables, the Pearson correlation coefficient was calculated, and Multivariate linear regression models were adjusted using the stepwise variable selection method, with Akaike Information Criterion (p ≤ 0.05).

RESULTS

BIA variables with the highest correlations with anthropometric measures were total body water (TBW), body fat percentage (BFP), FM, FFM and FM/FFM. The multiple linear regression analysis showed, in general, that the same variables can be estimated through simple anthropometric measures.

CONCLUSIONS

The assessment of fat distribution in the body is desirable for the diagnosis and definition of obesity severity. However, the high cost of the instruments (dual energy X-ray absorptiometry, hydrostatic weighing, air displacement plethysmography, computed tomography, magnetic resonance) to assess it, favors the use of BMI in the clinical practice. Nevertheless, BMI does not represent a real fat distribution and body fat percentage. This highlights the relevance of the findings of the current study, since simple anthropometric variables can be used to estimate important BIA variables that are related to fat distribution and body composition.

Longitudinal association between muscle loss and mortality in ever-smokers

BACKGROUND

Body composition measures, specifically low weight or reduced muscle mass, are associated with mortality in chronic obstructive pulmonary disease (COPD), but the effect of longitudinal body composition changes is undefined.

RESEARCH QUESTION

Is the longitudinal loss of fat-free mass (FFM) associated with increased mortality including in those with initially normal or elevated body composition metrics?

STUDY DESIGN AND METHODS

Participants with complete data for at least one visit in the COPDGene (n=9,268) and ECLIPSE studies (1,760) were included and followed for 12 and 8 years, respectively. Pectoralis muscle area (PMA) was derived from thoracic CT scans and used as a proxy for FFM. A longitudinal mixed sub-model for PMA and a Cox proportional hazards sub-model for survival were fitted on a joint distribution using a shared random intercept parameter and Markov chain Monte Carlo parameter estimation.

RESULTS

Both cohorts demonstrated a left shifted distribution of baseline FFM, not reflected in BMI, and an increase in all-cause mortality risk associated with longitudinal loss of PMA. For each one cm2 PMA loss, mortality increased 3.1% (95% CI 2.4, 3.7, p<0.001) in COPDGene, and 2.4% (95% CI 0.9, 4.0, p<0.001) in ECLIPSE. Increased mortality risk was independent of enrollment values for BMI and disease severity (BODE index quartiles) and was significant even in participants with initially greater than average PMA.

INTERPRETATION

Longitudinal loss of PMA is associated with increased all-cause mortality, regardless of BMI or initial muscle mass. Consideration of novel screening tests and further research into mechanisms contributing to muscle decline may improve risk stratification and identify novel therapeutic targets in ever-smokers.

Association of the fat-free mass index with mortality in patients with cancer: A multicenter observational study

OBJECTIVES

Low fat-free mass index (FFMI) has been related to a higher mortality in community populations. However, information on the relationship between FFMI and mortality is lacking for patients with cancer. The objective of this study was to examine the association between FFMI and all-cause mortality in Chinese cancer patients.

METHODS

This retrospective analysis included data on 1744 patients with cancer from a multicenter cohort study. The restricted cubic splines were used to flexibly model the association of FFMI with all-cause mortality. The association between low FFMI and overall survival was analyzed with the Kaplan-Meier method and a Cox model.

RESULTS

Among all patients, there were 702 men (40.3%) and 1042 women (59.7%). The optimal cutoff point of low FFMI was 16.31 for men and 14.14 for women. The FFMI showed an inverse association with all-cause mortality for men (per standard deviation [SD] increment; hazard ratio [HR]: 0.72; 95% confidence interval [CI], 0.60-0.87; P < 0.001) and a nonlinear relation for women (per SD increment; HR: 0.88; 95% CI, 0.78-0.99; P = 0.048). After adjustment, a low FFMI score was independently associated with an increased risk of mortality for both men and women. In addition, FFMI showed a strong L-shape (per SD increment; HR: 0.59; 95% CI, 0.46-0.76; P < 0.001) relation with all-cause mortality in elderly patients with cancer. For specific tumor type, a low FFMI score was independently associated with worse prognosis in patients with lung and upper gastrointestinal cancer.

CONCLUSIONS

A low FFMI score was associated with all-cause mortality in patients with cancer, especially for elder adults with cancer. These results highlight the usefulness of the FFMI for routine clinical assessment and prognostic estimation in patients with cancer.

Development of muscle mass and body fat reference curves for white male UK firefighters

OBJECTIVE

This study describes the development of the world's first suite of firefighter body composition centile reference curves which can be used as both academic research tools and clinical references, to plot and track individual firefighter skeletal muscle mass (SMM) and fat mass (FM) measurements against the representative reference sample.

METHODS

The body composition of 497 white male London (England) firefighters was measured by anthropometry and bioelectrical impedance analysis. Smoothed centile curves were then generated for skeletal muscle mass index (SMMI), fat mass index (FMI), body fat percentage (BF%) and waist-to-height ratio (WHtR).

RESULTS

Between 48 and 62 years, firefighter SMMI is greater than the UK white male age-matched general population by a mean of 0.35 units, although SMMI declines 0.006 units/years faster in firefighters between these ages. This is estimated to translate to a mean decline of approximately 0.6% of absolute SMM per year. Between 40 and 49 years, firefighter FMI is 0.1 units greater than the UK white male age-matched general population, which becomes identical (7 units) between 50 and 54 years. At the 50th centile, WHtR exceeds 0.5 by 39 years reaching 0.55 at 62 years. This contrasts with FMI which remains stable from 47 years.

CONCLUSION

Firefighters in this study possess greater FM and SMM compared with the UK general population. SMM appears to decline rapidly within older age ranges. These references offer a novel improvement upon the limitations of BMI and BF% for the benefit of an occupational group at elevated risk of cardiovascular disease.

Relationship between body composition, exercise capacity and health-related quality of life in idiopathic pulmonary fibrosis

INTRODUCTION

Bioelectrical impedance analysis (BIA) can be used to estimate Fat-Free Mass Index (FFMI). However, the use of directly measured BIA variables, such as phase angle (PhA), has gained attention. The frequency of low FFMI and PhA and its associations with exercise capacity and health-related quality of life (HRQL) in patients with idiopathic pulmonary fibrosis (IPF) have been scarcely studied.

OBJECTIVES

To investigate the frequency of low FFMI and PhA and their associations with exercise capacity and HRQL in patients with IPF.

METHODS

Patients underwent assessment of lung function, body composition, exercise capacity by the 6 min walk distance (6MWD), and HRQL by the Medical Outcomes Study Short-Form 36-item Questionnaire (SF-36). Patients were classified as presenting normal or low PhA or FFMI, accordingly to the 10th percentiles of age-sex-body mass index (BMI)-specific reference values.

RESULTS

98 patients (84 males, age: 68±8 years, forced vital capacity: 64%±18%predicted) were included. 24 patients presented low PhA. They were characterised by worse lung function, exercise capacity and HRQL compared with patients with normal PhA. 10 patients presented low FFMI, but despite differences in body composition, no differences were found between these patients and patients with normal FFMI. In a single regression analysis, age, lung function and body composition variables (except FFMI) were related to 6MWD and SF-36 Physical Summary Score (R²=0.06-0.36, p<0.05). None of the variables were related to SF-36 Mental Summary Score.

CONCLUSION

One-fourth of the patients with IPF with normal to obese BMI present abnormally low PhA. Patients classified as low PhA presented worse lung function, exercise capacity and HRQL.

Estimation of Muscle Mass in the Integrated Assessment of Patients on Hemodialysis

Assessment of muscle mass (MM) or its proxies, lean tissue mass (LTM) or fat-free mass (FFM), is an integral part of the diagnosis of protein-energy wasting (PEW) and sarcopenia in patients on hemodialysis (HD). Both sarcopenia and PEW are related to a loss of functionality and also increased morbidity and mortality in this patient population. However, loss of MM is a part of a wider spectrum, including inflammation and fluid overload. As both sarcopenia and PEW are amendable to treatment, estimation of MM regularly is therefore of major clinical relevance. Whereas, computer-assisted tomography (CT) or dual-energy X-ray absorptiometry (DXA) is considered a reference method, it is unsuitable as a method for routine clinical monitoring. In this review, different bedside methods to estimate MM or its proxies in patients on HD will be discussed, with emphasis on biochemical methods, simplified creatinine index (SCI), bioimpedance spectroscopy (BIS), and muscle ultrasound (US). Body composition parameters of all methods are related to the outcome and appear relevant in clinical practice. The US is the only parameter by which muscle dimensions are measured. BIS and SCI are also dependent on either theoretical assumptions or the use of population-specific regression equations. Potential caveats of the methods are that SCI can be influenced by residual renal function, BIS can be influenced by fluid overload, although the latter may be circumvented by the use of a three-compartment model, and that muscle US reflects regional and not whole body MM. In conclusion, both SCI and BIS as well as muscle US are all valuable methods that can be applied for bedside nutritional assessment in patients on HD and appear suitable for routine follow-up. The choice for either method depends on local preferences. However, estimation of MM or its proxies should always be part of a multidimensional assessment of the patient followed by a personalized treatment strategy.

The Application of Fat-Free Mass Index for Survival Prediction in Cancer Patients With Normal and High Body Mass Index

Background: Fat-free mass (FFM) depletion can be masked by a stable body weight or weight gain in the presence of a normal or high body mass index (BMI). This study investigated the prognostic value of low fat-free mass index (FFMI) in cancer patients with normal or high BMI.

Methods: This multicenter retrospective cohort study included 1,602 cancer patients with normal/high BMI. The association of FFMI with patients' overall survival (OS) was analyzed by the Kaplan-Meier method and a Cox model.

Results: In this analysis, there were 974 (60.8%) females and 628 (39.2%) males. Low FFMI was associated with worse OS when compared with those patients with normal FFMI. After multivariate adjustment, low FFMI was demonstrated to be an independent unfavorable prognostic factor (HR: 1.69; 95% CI: 1.28, 2.23; P < 0.001) in cancer patients with normal/high BMI. For specific tumor type, low FFMI was found to be associated with worse prognosis in patients with lung cancer, breast cancer and upper gastrointestinal cancer. In subgroup analysis, the association of low FFMI with worse survival was significantly modified by weight loss (P for interaction = 0.012), and those patients with concurrent low FFMI and weight loss showed the worst prognosis (HR: 3.53; 95% CI: 2.04, 6.11; P < 0.001).

Conclusion: Low FFMI was associated with worse prognosis in cancer patients with normal/high BMI. This study highlights the usefulness of FFMI for prognostic estimation in these patients.

Longitudinal changes in total and regional body composition in patients with chronic obstructive pulmonary disease

Background and objective

Low fat‐free mass (FFM) is common in patients with chronic obstructive pulmonary disease (COPD) and contributes to morbidity and mortality. Few studies have evaluated longitudinal changes in body composition in patients with COPD compared with non‐COPD controls. This study aimed to compare longitudinal changes in total and regional body composition between patients with COPD and non‐COPD controls and investigate predictors of changes in body composition in COPD.

Methods

Patients with COPD and non‐COPD controls participating in the Individualized COPD Evaluation in relation to Ageing (ICE‐Age) study, a single‐centre, longitudinal, observational study, were included. Subjects were assessed at baseline and after 2 years of follow‐up. Among other procedures, body composition was measured by dual‐energy X‐ray absorptiometry scan. The number of exacerbations/hospitalizations 1 year before inclusion and during follow‐up were assessed in patients with COPD.

Results

A total of 405 subjects were included (205 COPD, 87 smoking and 113 non‐smoking controls). Patients with COPD and smoking controls presented a significant decline in total FFM (mean [95% CI]: −1173 [−1527/−820] g and −486 [−816/−156] g, respectively) while body composition remained stable in non‐smoking controls. In patients with COPD, the decline in FFM was more pronounced in legs (−174 [−361/14] g) and trunk (−675 [−944/406] g) rather than in arms (54 [−19/126] g). The predictors of changes in total and regional FFM in patients with COPD were gender, number of previous hospitalizations, baseline values of FFM and BMI.

Conclusion

Patients with COPD present a significant decline in FFM after 2 years of follow‐up, this decline is more pronounced in their legs and trunk.

Patients with chronic obstructive pulmonary disease (COPD) present a significant decline in total, leg and trunk low fat‐free mass (FFM), while arms FFM remains stable after 2 years of follow‐up. We identified a subgroup of patients with preserved FFM at baseline and history of previous hospitalizations that present greater decline in total and leg FFM compared to other patients with COPD.

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Body Composition and Selected Nutritional Indicators in Healthy Adults-A Cross-Sectional Study

Background

Body mass composition is subject to constant change and is multifactorially determined. Its analysis in different age groups allows a better understanding of the determinants of the human organism in health and disease.

Aim

The study was aimed to conduct cross-sectional assessment of body composition and selected nutritional indicators in healthy adults.

Methods

The cross-sectional study carried out from March 2016 to April 2018 was preceded by a monthly pilot study. All 1333 adults (women 795, 59.6%) aged 20–59 included in the study were from the urban and rural area of the Podkarpackie Province (Poland). These adults were classified into four 10-year age bands. To obtain reliable assessment, selected screening (anthropometry) and in-depth (bioelectrical impedance including phase angle and bioelectrical impedance vector analysis) methods were used.

Results

In women, the proportion of individuals affected by overweight and obesity increases significantly with age, with a less pronounced trend in men, as reflected in the observed differences in individual body composition components. A slight (0.45–0.60) correlation was also observed between body mass index (BMI) and percentage of fat mass (FM %) among men with an increasing strength of the association with age, decreasing in the 50–59 years group. In the female group, the correlations described are at a much higher level (0.80 or higher). The described changes in body composition were reflected in body type from athletic to obese, measured by means of the bioelectrical impedance vector analysis (BIVA) method.

Conclusions

Age and gender significantly differentiate body composition of the adult human body. The body composition analysis should be considered as complement screening assessment method, especially as a support for the assessment of nutritional status expressed by BMI.

Characteristics of chronic obstructive pulmonary disease patients with robust progression of emphysematous change

Emphysema is a major pathological change in chronic obstructive pulmonary disease (COPD). However, the annual changes in the progression of emphysematous have not been investigated. We aimed to determine possible baseline predicting factors of the change in emphysematous progression in a subgroup of COPD patients who demonstrated rapid progression. In this observational study, we analyzed patients with COPD who were followed up by computed tomography (CT) at least two times over a 3-year period (n = 217). We divided the annual change in the low attenuation area percentage (LAA%) into quartiles and defined a rapid progression group (n = 54) and a non-progression group (n = 163). Predictors of future changes in emphysematous progression differed from predictors of high LAA% at baseline. On multivariate logistic regression analysis, low blood eosinophilic count (odds ratio [OR], 3.22; P = 0.04) and having osteoporosis (OR, 2.13; P = 0.03) were related to rapid changes in emphysematous progression. There was no difference in baseline nutritional parameters, but nutritional parameters deteriorated in parallel with changes in emphysematous progression. Herein, we clarified the predictors of changes in emphysematous progression and concomitant deterioration of nutritional status in COPD patients.

Associations of Skeletal Muscle Mass and Fat Mass With Incident Cardiovascular Disease and All-Cause Mortality: A Prospective Cohort Study of UK Biobank Participants

Background There is debate whether body mass index is a good predictor of health outcomes because different tissues, namely skeletal muscle mass (SMM) and fat mass (FM), may be differentially associated with risk. We investigated the association of appendicular SMM (aSMM) and FM with fatal and nonfatal cardiovascular disease (CVD) and all-cause mortality. We compared their prognostic value to that of body mass index. Methods and Results We studied 356 590 UK Biobank participants aged 40 to 69 years with bioimpedance analysis data for whole-body FM and predicted limb muscle mass (to calculate aSMM). Associations between aSMM and FM with CVD and all-cause mortality were examined using multivariable Cox proportional hazards models. Over 3 749 501 person-years of follow-up, there were 27 784 CVD events and 15 844 all-cause deaths. In men, aSMM was positively associated with CVD incidence (hazard ratio [HR] per 1 SD 1.07; 95% CI, 1.06-1.09) and there was a curvilinear association in women. There were stronger positive associations between FM and CVD with HRs per SD of 1.20 (95% CI, 1.19-1.22) and 1.25 (95% CI, 1.23-1.27) in men and women respectively. Within FM tertiles, the associations between aSMM and CVD risk largely persisted. There were J-shaped associations between aSMM and FM with all-cause mortality in both sexes. Body mass index was modestly better at discriminating CVD risk. Conclusions FM showed a strong positive association with CVD risk. The relationship of aSMM with CVD risk differed between sexes, and potential mechanisms need further investigation. Body fat and SMM bioimpedance measurements were not superior to body mass index in predicting population-level CVD incidence or all-cause mortality.

Frequency and functional translation of low muscle mass in overweight and obese patients with COPD

BACKGROUND

Cut offs for fat-free mass index (FFMI) and appendicular skeletal muscle mass index (ASMI) are available for diagnosing low muscle mass in patients with COPD. This study aimed to investigate: (1) the frequency of low muscle mass (FFMI and ASMI) applying different cut-offs and (2) the functional translation (clinical impact) of low muscle mass, in patients with COPD stratified into BMI categories.

METHODS

Patients with COPD were assessed regarding body composition, exercise capacity, quadriceps muscle strength, symptoms of anxiety and depression, dyspnea and quality of life upon referral to pulmonary rehabilitation. The proportion of patients with low muscle mass was compared among BMI categories. Clinical outcomes between patients with normal and low muscle mass within each BMI category were compared.

RESULTS

469 patients with COPD were included for analyses. The frequency of patients classified as low FFMI varied significantly according to the choice of cut-off (32 to 54%; P < 0.05), whereas the frequency of patients with low ASMI was 62%. When applying age-gender-BMI-specific cut-offs, 254 patients (54%) were classified as low FFMI. The choice of the cut-off affected the frequency of patients with low muscle mass in all BMI categories. Overweight and obese patients with low muscle mass were more frequently males and presented worse pulmonary function, exercise capacity and muscle strength compared with overweight and obese patients with normal muscle mass.

CONCLUSIONS

Approximately half of the overweight and obese patients with COPD have low muscle mass when applying age-gender-BMI-specific cut-offs. Low muscle mass is associated with worse functional outcomes in overweight and obese COPD patients.

Effect of fat mass index, fat free mass index and body mass index on childhood blood pressure: a cross-sectional study in south China

BACKGROUND

Evidence on how different body composition indexes, such as body mass index (BMI), fat mass index (FMI) and fat free mass index (FFMI), influence blood pressure (BP) in Chinese children and adolescents is sparse. The aim of this study is to assess the effect of different body composition on BP in participants aged 7-18 in south China.

METHODS

A cross-sectional study was conducted in 2013. A total of 1,609 children and adolescents from urban and rural areas in Hainan Province, South China, were selected using multi-stage stratified cluster sampling method. Each participant underwent anthropometric and BP tests. BMI, FMI and FFMI were calculated and analyzed as body composition indexes.

RESULTS

In the population level stratified by sex, FFMI had the highest r-value (Partial Spearman correlations) of correlation with systolic BP in boys (r_s=0.305, P<0.001) and girls (r_s=0.237, P<0.001). FMI was found to have the highest r-value of correlation with DBP in boys (r_s=0.154, P<0.001). The quantile regression model indicated that, within each age group, all body composition indexes was positively associated with systolic BP, and FFMI has the greatest value of regression coefficient (4.38, 95% CI: 3.81-4.95). But for diastolic BP, positive associations with BMI, FMI and FFMI were only observed in the 11-12 years group. Restrict cubic spline models showed that there were both linear and non-linear relations between BMI, FMI and BP, but for FFMI, there was only linear association with BP.

CONCLUSIONS

The relation between BP and FFMI was stronger than with BMI and FMI. Combined measurement of body composition should be considered to help health professionals interpret body mass data from children and adolescents with varied stature and age.

Positive Associations of Dietary Intake and Plasma Concentrations of Vitamin E with Skeletal Muscle Mass, Heel Bone Ultrasound Attenuation and Fracture Risk in the EPIC-Norfolk Cohort

The prevalence of sarcopenia, frailty and fractures is increasing. Prevention options are limited, but dietary factors including vitamin E have the potential to confer some protection. This study investigated cross-sectional associations between dietary and plasma concentrations of vitamin E with indices of skeletal muscle mass (SMM) (n = 14,179 and 4283, respectively) and bone density (n = 14,694 and 4457, respectively) and longitudinal fracture risk (n = 25,223 and 7291, respectively) in European Prospective Investigation Into Cancer and Nutrition (EPIC)-Norfolk participants, aged 39-79 years at baseline. Participants completed a health and lifestyle questionnaire, a 7-day diet diary (7dDD) and had anthropometric measurements taken. Fat-free mass (as a SMM proxy) was measured using bioimpedance and bone density was measured using calcaneal broadband ultrasound attenuation (BUA) and incident fractures over 18.5 years of follow-up. Associations between indices of SMM, BUA and fracture risk were investigated by quintiles of dietary vitamin E intake or plasma concentrations. Positive trends in SMM indices and BUA were apparent across dietary quintiles for both sexes, with interquintile differences of 0.88%-1.91% (p < 0.001), and protective trends for total and hip fracture risk. Circulating plasma α- and γ-tocopherol results matched the overall dietary findings. Dietary vitamin E may be important for musculoskeletal health but further investigation is required to fully understand the relationships of plasma tocopherols.

Towards Personalized Management of Sarcopenia in COPD

The awareness of the presence and consequences of sarcopenia has significantly increased over the past decade. Sarcopenia is defined as gradual loss of muscle mass and strength and ultimately loss of physical performance associated with aging and chronic disease. The prevalence of sarcopenia is higher in chronic obstructive pulmonary disease (COPD) compared to age-matched controls. Current literature suggests that next to physical inactivity, COPD-specific alterations in physiological processes contribute to accelerated development of sarcopenia. Sarcopenia in COPD can be assessed according to current guidelines, but during physical performance testing, ventilatory limitation should be considered. Treatment of muscle impairment can halt or even reverse sarcopenia, despite respiratory impairment. Exercise training and protein supplementation are currently at the basis of sarcopenia treatment. Furthermore, effective current and new interventions targeting the pulmonary system (eg, smoking cessation, bronchodilators and lung volume reduction surgery) may also facilitate muscle maintenance. Better understanding of disease-specific pathophysiological mechanisms involved in the accelerated development of sarcopenia in COPD will provide new leads to refine nutritional, exercise and physical activity interventions and develop pharmacological co-interventions.

Comprehensive health assessment three months after recovery from acute COVID-19

Background

Long-term health sequelae of coronavirus disease 2019 (COVID-19) may be multiple but have thus far not been systematically studied.

Methods

All patients discharged after COVID-19 from the Radboud University Medical Center, Nijmegen, the Netherlands, were consecutively invited to a multidisciplinary outpatient facility. Also, nonadmitted patients with mild disease but with symptoms persisting >6 weeks could be referred by general practitioners. Patients underwent a standardized assessment including measurements of lung function, chest computed tomography (CT)/X-ray, 6-minute walking test, body composition, and questionnaires on mental, cognitive, health status, and quality of life (QoL).

Results

124 patients (59 ± 14 years, 60% male) were included: 27 with mild, 51 with moderate, 26 with severe, and 20 with critical disease. Lung diffusion capacity was below the lower limit of normal in 42% of discharged patients. 99% of discharged patients had reduced ground-glass opacification on repeat CT imaging, and normal chest X-rays were found in 93% of patients with mild disease. Residual pulmonary parenchymal abnormalities were present in 91% of discharged patients and correlated with reduced lung diffusion capacity. Twenty-two percent had low exercise capacity, 19% low fat-free mass index, and problems in mental and/or cognitive function were found in 36% of patients. Health status was generally poor, particularly in the domains functional impairment (64%), fatigue (69%), and QoL (72%).

Conclusions

This comprehensive health assessment revealed severe problems in several health domains in a substantial number of ex–COVID-19 patients. Longer follow-up studies are warranted to elucidate natural trajectories and to find predictors of complicated long-term trajectories of recovery.

Lower Dietary and Circulating Vitamin C in Middle- and Older-Aged Men and Women Are Associated with Lower Estimated Skeletal Muscle Mass

BACKGROUND

Age-related loss of skeletal muscle mass contributes to poor outcomes including sarcopenia, physical disability, frailty, type 2 diabetes, and mortality. Vitamin C has physiological relevance to skeletal muscle and may protect it during aging, but few studies have investigated its importance in older populations.

OBJECTIVES

We aimed to investigate cross-sectional associations of dietary and plasma vitamin C with proxy measures of skeletal muscle mass in a large cohort of middle- and older-aged individuals.

METHODS

We analyzed data from >13,000 men and women in the European Prospective Investigation into Cancer and Nutrition-Norfolk cohort, aged 42-82 y. Fat-free mass (FFM), as a proxy for skeletal muscle mass, was estimated using bioelectrical impedance analysis and expressed as a percentage of total mass (FFM%) or standardized by BMI (FFMBMI). Dietary vitamin C intakes were calculated from 7-d food diary data, and plasma vitamin C was measured in peripheral blood. Multivariable regression models, including relevant lifestyle, dietary, and biological covariates, were used to determine associations between FFM measures and quintiles of dietary vitamin C or insufficient compared with sufficient plasma vitamin C (<50 μmol/L and ≥50 μmol/L).

RESULTS

Positive trends were found across quintiles of dietary vitamin C and FFM measures for both sexes, with interquintile differences in FFM% and FFMBMI of 1.0% and 2.3% for men and 1.9% and 2.9% for women, respectively (all P < 0.001). Similarly, FFM% and FFMBMI measures were higher in participants with sufficient than with insufficient plasma vitamin C: by 1.6% and 2.0% in men, and 3.4% and 3.9% in women, respectively (all P < 0.001). Associations were also evident in analyses stratified into <65-y and ≥65-y age groups.

CONCLUSIONS

Our findings of positive associations, of both dietary and circulating vitamin C with measures of skeletal muscle mass in middle- and older-aged men and women, suggest that dietary vitamin C intake may be useful for reducing age-related muscle loss.

Phase Angle Evaluation of Lung Disease Patients and Its Relationship with Nutritional and Functional Parameters

BACKGROUND

This study aimed to determine the value of phase angle (PhA) in patients with chronic obstructive pulmonary disease (COPD) and pulmonary hypertension (PH) and its association with nutritional and functional parameters.

METHODS

A cross-sectional study of 77 patients under follow-up at the pulmonary outpatient clinic of a public hospital. Anthropometric measurements and functional assessments of physical and pulmonary capacity were performed, and a regular physical activity questionnaire was administered.

RESULTS

The sample consisted of 38 patients with COPD (mean age, 63.8 ± 9.9 years; 68.4% female) and 39 patients with PH (mean age, 46.6 ± 14.4 years; 79.5% female). There was no difference in anthropometric measurements between patients with COPD and PH. Patients with COPD had mild to moderate limitations of pulmonary function, while patients with PH had only mild limitations (p < 0.01). Although the median distance covered in the 6-minute walk test (6MWT) was different between the COPD and PH groups (p < 0.05), it was considered adequate for these populations. Mean PhA was within the range considered adequate in patients with COPD (6.3°±1°) and PH (6.2°±0.8°) (p > 0.05). In the statistical analyses, although the correlations were weak, adequate PhA correlated with fat free mass index, 6MWT, disease staging, forced vital capacity, and forced expiratory volume in the first second.

CONCLUSION

The anthropometric profile of both patient groups was very similar, and PhA values were within the expected range. Despite weak correlations, PhA is a clinical component to be followed and investigated in patients with lung disease.

Should we overcome the resistance to bioelectrical impedance in heart failure?

INTRODUCTION

Heart failure is associated with increased neurohormonal activation that results in changes in body composition including volume overload and the loss of skeletal muscle, body fat, and bone density. Bioelectrical impedance measures body composition based on the conduction of electrical current through body fluids.

AREAS COVERED

The PubMed and Scopus databases were reviewed up to the third week of June 2020. Cross-sectional studies, retrospective observational studies, prospective observational studies, and randomized controlled trials have examined numerous bioelectrical impedance monitoring strategies to guide the diagnosis, prognosis, and treatment of heart failure. These monitoring strategies include intrathoracic impedance, lung impedance, bioelectrical impedance vector analysis, leg bioelectrical impedance, and thoracic bioreactance.

EXPERT COMMENTARY

Based on the current evidence, more studies are needed to validate bioelectrical impedance in heart failure. Lung impedance appears to be useful for guiding heart failure treatment in patients with ST-elevation myocardial infarction and improving outcomes in outpatients with heart failure. Furthermore, bioelectrical impedance has potential as a noninvasive, quantitative heart failure variable for population-based research.