Identification of skeletal muscle mass depletion across age and BMI groups in health and disease--there is need for a unified definition

The decorin and myostatin response to acute whole body vibration: impact of adiposity, sex, and race

BACKGROUND

Traditional forms of exercise affect immune, metabolic, and myokine responses and contribute to a multitude of health benefits. Whole body vibration (WBV) has recently emerged as an exercise mimetic that may be more tolerable for those individuals that cannot perform traditional exercise. However, the myokines response to acute WBV in humans has yet to be fully elucidated.

OBJECTIVE

To characterize the decorin and myostatin response to acute whole body vibration (WBV) and determine the impact of adiposity, sex, and race.

SUBJECTS

One hundred twenty-nine adults (32.8 ± 0.4 years, 66.7% female, 53.5% non-Hispanic Black) were recruited as part of an ongoing, longitudinal twin cohort parent study. Participants were classified into three groups: those with obesity (OB: ≥30 kg/m2), those who are overweight (OW: ≥25 and <30 kg/m2), or those with normal weight (NW: <25 kg/m2) based on BMI.

METHODS

Blood was collected at baseline (PRE), immediately post (POST), and 1 h (1H), 3 h (3H), and 24 h (24H) post WBV. The acute WBV protocol consisted of 10 cycles of 1 min of vibration exercise followed by 30 s of standing rest.

RESULTS

The response was similar between NW and OW, so these groups were combined for analysis (NW/OW: BMI < 30 kg/m2). Overall, circulating concentrations of decorin were higher (p < 0.001) POST (8.80 ± 0.19 pg/mL) and significantly lower (p's ≤ 0.005) at 1H (8.66 ± 0.19 pg/mL) and 3H (8.68 ± 0.19 pg/mL), compared to PRE (8.71 ± 0.19 pg/mL). Decorin POST was greater (p = 0.016) in the OB group (8.82 ± 0.18 pg/mL) compared to the NW/OW group (8.77 ± 0.20 pg/mL). Overall, myostatin was higher (p = 0.002) POST (54.93 ± 1.04 pg/mL) and lower (p < 0.001) at 24H (49.13 ± 1.04 pg/mL) compared to PRE (53.49 ± 1.04 pg/mL). The myostatin response was lower (p's ≤ 0.001) in female and non-Hispanic White individuals compared to male and non-Hispanic Black individuals, respectively.

CONCLUSIONS

A single bout of WBV can facilitate the release of decorin and myostatin into circulation, a similar response to traditional exercise. Additionally, adiposity, sex and race should be considered when evaluating the myokines response to WBV.

Prevalence of low-body cell mass evaluated by bioelectrical impedance vector analysis related to aging

OBJECTIVE

The objective of this study was to determine the prevalence of low-body cell mass by sex and age in a community-dwelling population.

METHODS

In this retrospective study, 981 community-dwelling adults aged ≥35 years (648 women and 333 men) from Mexico City were recruited in a subway station between February and April 2012. Demographic data, anthropometry, and body composition were assessed, and self-reported comorbidities were recorded in the consulting room. Impedance values were obtained using mono-frequency equipment at 50 kHz. For the diagnosis of low-body cell mass by bioelectrical impedance vectorial analysis: resistance (R, Ohm) and reactance (Xc, Ohm) values were adjusted for height to obtain impedance vector (R/H and Xc/H) and then plotted in the R/Xc to perform the bioelectrical impedance vectorial analysis RXc Z-score analysis.

RESULTS

The total prevalence of low body cell mass by bioelectrical impedance vectorial analysis was 29.4% (n=288) with a 95%CI 26.5-32.3%; was higher in men (39%) compared with women (24.4%) (p<0.0001). The group aged>75 years had the highest prevalence (men: 85.3%, p<0.001; women: 63.3%, p<0.001). The bioelectrical impedance vectorial analysis RXc Z-score analysis showed lower cell mass in men aged>75 years (R Z-score -0.30, Xc Z-score -2.13), and women aged 65-74 years also presented with overhydration (Z-score -2.6, Z-score -1.27).

CONCLUSION

The prevalence of low body cell mass, evaluated by bioelectrical impedance vectorial analysis, increased with age. RXc Z-score analysis could be a useful tool to evaluate nutritional status and changes in hydration in community-dwelling populations.

The Normal Weight Obesity (NWO) Problem-Prevalence and Time Changes in Children and Adolescents From Kraków (Poland)

OBJECTIVES

Normal weight obesity can be associated with an increased risk of metabolic abnormalities, systemic inflammation and mortality. The main aim of the study was to analyze the changes in the prevalence of normal weight obesity in 8-18-year-olds from Kraków (Poland) between 2010 and 2020.

METHODS

The study was based on two sets of cross-sectional, school-based data obtained in 2010 and 2020. Body height, weight, and fat percentage were obtained. Body mass index was calculated, and only normal-weight individuals were included. Normal weight obesity was defined as normal BMI with adiposity >85 percentile for age and sex.

RESULTS

The prevalence of normal weight obesity among Polish children and adolescents has been alarming for at least the last 10 years. Depending on the sex and age, normal weight obesity was present in more than 10% up to even more than 20% of the examined population.

CONCLUSIONS

Alarming numbers of Polish children and adolescents suffer from NWO and this problem seems to be present for at least the last decade. A need for a maximally universal definition and cut-offs to diagnose normal weight obesity should also be stressed, as it will be helpful in providing the best prophylaxis and help to persons already suffering from normal weight obesity.

Relationship between relative fat mass and infertility: A cross-sectional study

Infertility is closely related to obesity. Relative fat mass (RFM) is a newer index for assessing percentage of body fat, which reflects the amount of body fat better than body mass index (BMI), but its relationship with infertility needs further study. The purpose of this study was to assess whether there was an association between RFM and infertility in women aged 20 to 44 years in the United States. The corresponding participants were selected from the National Health and Nutrition Examination Survey (NHANES) 2013 to 2018. RFM was used as the independent variable and infertility as the dependent variable. Multiple logistic regression and generalized additive models were used to explore the association between RFM and infertility, 2-stage linear regression models were used to calculate threshold effects, and subgroup analyses and tests of interactivity were used to find sensitive populations. A total of 2328 women aged 20 to 44 years were included. In the fully adjusted model, the risk of infertility increased by 6% for each increase in RFM (OR = 1.06, 95% CI: 1.00-1.12). There was a nonlinear relationship between RFM and infertility with 2 breakpoints of K1 = 31.04 and K2 = 48.4. There was a positive association between RFM and infertility on the right side of K1 and, on the left side of K2 (OR = 1.08, 95% CI: 1.01-1.16; OR = 1.07, 95% CI: 1.01-1.14). In contrast, no statistically significant association between RFM and infertility was found on the left side of K1 as well as on the right side of K2. There was a nonlinear relationship between RFM and infertility, with a positive association with infertility when RFM was in the range of 31.04 to 48.4.This suggests that RFM may be an alternative to BMI in the management of obese infertile women, but this needs to be further confirmed by prospective studies.

Prognostic value of body composition in patients with digestive tract cancers: A prospective cohort study of 8,267 adults from China

BACKGROUND & AIMS

The characterization and prognostic value of body composition parameter/phenotype based on computed tomography (CT) in patients with digestive tract cancers remain incomplete. This study aimed to investigate the relationship between parameter/phenotype and clinical outcomes in patients with digestive tract cancers.

METHODS

In this prospective cohort study, 8267 patients with digestive tract cancers were assessed using CT scans to determine body composition. Body composition data, including areas of skeletal muscle (SM), subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT), were collected at the third lumbar level on CT images obtained within 30 days before surgery. Body composition phenotypes (sarcopenia, cancer cachexia, sarcopenic obesity) were determined based on SM, SAT, and VAT areas. The primary endpoint was overall survival, obtained from electronic medical records and telephone follow-up surveys. Kaplan-Meier and log-rank analyses were employed to compare unadjusted survival, while multivariate survival analyses were conducted using a proportional hazards model adjusted for age, gender, and cancer-node-metastasis (TNM) stages.

RESULTS

Adjusted hazard ratios (HRs) for all-cause mortality were calculated for the second (Q2), third (Q3), and fourth (Q4) quantiles relative to the first quantile (Q1) for SM areas, revealing adjusted summary HRs of 0.575 (95% CI, 0.361-0.916), 0.419 (95% CI, 0.241-0.729), and 0.384 (95% CI, 0.203-0.726), respectively. Sarcopenia-adjusted summary HRs were 1.795 (95% CI: 1.012-3.181) for male patients and 1.925 (95% CI: 1.065-3.478) for female patients. Cancer cachexia-adjusted summary HRs were 1.542 (95% CI: 1.023-2.324) for male patients and 1.569 (95% CI: 0.820-3.001) for female patients. Sarcopenic obesity-adjusted summary HRs were 1.122 (95% CI: 0.759-1.657) for male patients and 1.303 (95% CI: 0.623-2.725) for female patients. Subgroup analyses indicated varying prognostic values of body composition parameter/phenotype among different cancer types.

CONCLUSIONS

Our findings suggest a large SM area is a favorable prognostic indicator, while cancer cachexia and sarcopenia signify poor prognosis in patients with digestive tract cancers. These findings have important implications for the personalized preoperative assessment of body composition in patients with digestive tract cancers.

Physical activity and fiber intake beneficial for muscle mass and strength preservation during aging: A comprehensive cross-sectional study in the UK biobank cohort

BACKGROUND

Aging triggers intricate physiological changes, particularly in whole-body fat-free mass (FFM) and handgrip strength, affecting overall health and independence. Despite existing research, the broader significance of how muscle health is affected by the intricate interplay of lifestyle factors simultaneously during aging needs more exploration. This study aims to examine how nutrition, physical activity, and sleep impact on FFM and handgrip strength in middle-aged men and women, facilitating future personalized recommendations for preserving muscle health.

METHODS

The cross-sectional analysis of the UK Biobank involved 45,984 individuals (54 % women) aged 40-70 years with a complete dataset. Multiple linear regression explored determinants of FFM and handgrip strength, considering traditional, socio-demographics, medication use and smoking as covariates, with sex and age (younger and older than 55 years) stratifications.

RESULTS

In older men and women, higher physical activity beneficially affect both FFM (respectively Β = 3.36 × 10-3, p-value = 1.66 × 10-3; Β = 2.52 × 10-3, p-value = 3.57 × 10-4) and handgrip strength (Β = 6.05 × 10-3, p-value = 7.99 × 10-5, Β = 8.98 × 10-3, p-value = 2.95 × 10-15). Similar results were found in fiber intake for FFM in older men and women (respectively B = 3.00 × 10-2, p-value = 2.76 × 10-5; B = 2.68 × 10-2, p-value = 1.78 × 10-9) and handgrip strength (Β = 3.27 × 10-2, p-value = 1.40 × 10-3; Β = 3.12 × 10-2, p-value = 1.34 × 10-5). Other lifestyle factors influence FFM and handgrip strength differently. Key determinants influencing handgrip strength included higher protein intake, lower water intake, higher alcohol intake, and extended sleep duration whereas mainly higher water intake is associated with higher FFM.

CONCLUSIONS

In both men and women, the main factors associated with FFM and handgrip strength are physical activity and fiber intake, which may underlie a connection between gut and muscle health. Given the observed complexity of muscle health in the age and sex strata, further longitudinal research is needed to provide personalized lifestyle recommendations.

Older Tissue Age Derived From Abdominal Computed Tomography Biomarkers of Muscle, Fat, and Bone Is Associated With Chronic Conditions and Higher Mortality

OBJECTIVE

To determine whether body composition derived from medical imaging may be useful for assessing biologic age at the tissue level because people of the same chronologic age may vary with respect to their biologic age.

METHODS

We identified an age- and sex-stratified cohort of 4900 persons with an abdominal computed tomography scan from January 1, 2010, to December 31, 2020, who were 20 to 89 years old and representative of the general population in Southeast Minnesota and West Central Wisconsin. We constructed a model for estimating tissue age that included 6 body composition biomarkers calculated from abdominal computed tomography using a previously validated deep learning model.

RESULTS

Older tissue age associated with intermediate subcutaneous fat area, higher visceral fat area, lower muscle area, lower muscle density, higher bone area, and lower bone density. A tissue age older than chronologic age was associated with chronic conditions that result in reduced physical fitness (including chronic obstructive pulmonary disease, arthritis, cardiovascular disease, and behavioral disorders). Furthermore, a tissue age older than chronologic age was associated with an increased risk of death (hazard ratio, 1.56; 95% CI, 1.33 to 1.84) that was independent of demographic characteristics, county of residency, education, body mass index, and baseline chronic conditions.

CONCLUSION

Imaging-based body composition measures may be useful in understanding the biologic processes underlying accelerated aging.

Are accelerometer-measured sitting and physical activity times associated with muscle mass and strength in healthy young adults in the UAE?

Background

A high prevalence of obesity, sedentary behavior, and physical inactivity could affect muscle mass and strength in young adults in the United Arab Emirates (UAE). Therefore, we investigated the association of sex, body mass index (BMI), and accelerometer-measured sitting and physical activity (PA) times with skeletal muscle mass index (SMI), hand grip, and thigh muscle strength in healthy young adults in the UAE.

Methods

In this cross-sectional study, 156 healthy young adults (age 21.68 ± 3.01 years, BMI 25.40 ± 4.79 kg/m2, 52.6 % women) were included. BMI and muscle mass were recorded using a bioelectrical impedance analyzer. Maximum hand grip strength and thigh muscle torque were assessed using the Jamar-smart hand-dynamometer and Biodex System-4-Pro, respectively. Participants wore a triaxial Fibion accelerometer on their anterior thigh for >10 h per day for 4-7 days to measure their sitting and PA times. Multiple linear regression analyses were used.

Results

Participants spent most of their time sitting (11.37 ± 1.10 h), followed by standing (2.92 ± 0.86 h), walking (1.58 ± 0.55 h), and vigorous intensity PA (4.79 ± 5.85 min) per 16-h day. Sex (p < 0.001) and BMI (p < 0.001) were negatively associated with all muscle mass and strength variables. Men had more muscle mass and strength than women. As BMI increased, muscle mass and muscle strength decreased. Accelerometer-measured sitting and walking times were negatively associated with concentric hamstrings (p = 0.044) and quadriceps torques (p = 0.031), respectively.

Conclusion

Sex, BMI, and accelerometer-measured sitting and walking times were associated with muscle mass and/or muscle strength in healthy young adults. Women and those with a high BMI need interventions to improve their muscle mass and strength. The paradox regarding the association of PA with muscle mass and strength in younger adults may be due to possible influences from other factors (e.g., resistance training, dietary intakes, etc.) superseding that of accelerometer-measured PA.

Association of body composition indices with cardiovascular outcomes: a nationwide cohort study

BACKGROUND

Previous studies regarding BMI (kg/m2) and associated cardiovascular outcomes yield inconsistent results.

OBJECTIVES

We aimed to investigate the association between body composition and cardiovascular outcomes according to BMI categories in the Korean general population.

METHODS

A total of 2,604,401 participants were enrolled in this nationwide cohort study using the National Health Insurance Service-Health Checkup data set. Predicted lean BMI (pLBMI), body fat mass index (pBFMI), and appendicular skeletal muscle mass index (pASMMI) were calculated using validated anthropometric prediction equations. A multivariable time-dependent Cox regression analysis was conducted to assess the association with cardiovascular outcomes. The results were presented with adjusted hazard ratios (HRs) with 95% confidence intervals (CIs), considering BMI categories (BMI < 18.5, BMI 18.5-24.9, BMI 25-29.9, and BMI ≥ 30).

RESULTS

Higher pLBMI and pASMMI were correlated with a reduced risk of composite cardiovascular outcomes. For pLBMI, HR was 0.910 (95% CI: 0.908, 0.913, P < 0.001) for males and 0.905 (95% CI: 0.899, 0.910, P < 0.001) for females. For pASMMI, HR was 0.825 (95% CI: 0.820, 0.829, P < 0.001) for males and 0.788 (95% CI: 0.777, 0.800, P < 0.001) for females. Conversely, a higher pBFMI was associated with an increased risk, with HR of 1.082 (95% CI: 1.071, 1.093, P < 0.001) for males and 1.181 (95% CI: 1.170, 1.192, P < 0.001) for females. Subgroup analysis based on BMI categories revealed no significant risk association for pBFMI in the BMI < 18.5 group. In the group with BMI ≥ 30, neither pLBMI nor pASMMI demonstrated a significant risk association.

CONCLUSIONS

Our results highlight the value of pLBMI, pBFMI, and pASMMI as variables for assessing risk of composite cardiovascular outcomes. The significance of indicators may vary depending on BMI categories.

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.

Impact of acute exacerbations of COPD on patients' health status beyond pulmonary function: A scoping review

This scoping review summarized the evidence regarding the impact of acute exacerbations of COPD (AECOPD) on patients' health status beyond pulmonary function. PubMed, Embase, and Web of Science were searched. Prospective cohort studies assessing the health status of patients with COPD in a stable phase of the disease and after a follow-up period (where at least one AECOPD occurred) were included. An integrated assessment framework of health status (i.e., physiological functioning, complaints, functional impairment, quality of life) was used. Twenty-two studies were included. AECOPD acutely affected exercise tolerance, quadriceps muscle strength, physical activity levels, symptoms of dyspnoea and fatigue, and impact of the disease. Long-term effects on quadriceps muscle strength, symptoms of dyspnoea and depression, and quality of life were found. Repeated exacerbations negatively impacted the fat-free mass, levels of dyspnoea, impact of the disease and quality of life. Conflicting evidence was found regarding the impact of repeated exacerbations on exercise tolerance and physical activity levels. AECOPD have well-established acute and long-term adverse effects on health status beyond pulmonary function; nevertheless, the recovery trajectory and the impact of repeated exacerbations are still poorly studied. Further prospective research is recommended to draw firm conclusions on these aspects.

Associations between physical activity, physical fitness, and body composition in adults living in Germany: A cross-sectional study

BACKGROUND & AIMS

Body composition (BC) changes with age and is associated with morbidity and mortality. A physically active lifestyle influences BC and represents an important predictor of successful aging. To emphasize this, the World Health Organization established activity recommendations for all age groups. We describe BC during adulthood using a cross-sectional sample from a German community and investigate the associations between physical activity (PA), physical fitness (PF), and BC.

METHODS

Data from 329 men and women aged 35 to 86 years were analyzed. PA was measured by questionnaire and classified into sport activity and habitual activity. PF was measured through physical performance tests and BC by bioelectrical impedance analysis. Fat mass index (FMI) and fat-free mass index (FFMI) were calculated to represent height-adjusted BC. Associations between PA, PF, and BC were analyzed using linear regression models.

RESULTS

For both sexes, strength was positively associated with FFMI (♂: ß = 0.313; ♀: ß = 0.213) and phase angle (♂: ß = 0.357; ♀: ß = 0.409). For FMI, a significant negative association with strength was found only in women (ß = -0.189). Cardiorespiratory fitness showed a negative association with FMI (ß = -0.312) and FFMI (ß = -0.201) for men, while in women a positive association was found for FFMI (ß = 0.186). For coordination, a significant association with FMI was observed only in women (ß = -0.190). Regarding PA only one significant relationship between sport activity and FMI among women (ß = -0.170) was found.

CONCLUSIONS

In our sample, PF was closer related to BC than PA. Strength and cardiorespiratory fitness were the strongest predictors for BC. This supports the World Health Organization's activity recommendations to include both resistance and endurance training in the weekly sports program to maintain a healthy BC.

Nutritional Risk of Candidates for Simultaneous Pancreatic-Kidney Transplantation-A Narrative Review

INTRODUCTION

Not much is known about the significance of nutritional status and support in transplant surgery, least of all in simultaneous pancreatic and kidney transplantation. Malnutrition in the context of simultaneous pancreatic-kidney transplantation seems to be complex and a still poorly investigated problem. Since SPKTX is highly qualified and also has a small volume procedure, it is difficult to obtain data from large cohorts of patients. The aim of this article is to gather existing evidence and information about the subject, as well as to elicit some questions and goals for the future.

METHODS

We searched through the Pub-Med database using the keywords "pancreas and kidney transplantation" combined with "nutritional risk", "nutritional status", "malnutrition", "nutritional intervention", and "frailty", finding a total of 4103 matching results. We then narrowed it down to articles written in English with the full text available. We also researched through the references of articles most accurately matching our researched terms.

RESULTS

There are numerous tools that have been investigated for the screening of malnutrition, such as the NRI index, PNI index, NLR, SGA scale, and NRS-2002 scale, each of which proved to be of some use in predicting patient outcomes in different surgical settings. Since all of them differed in components and assessed parameters and, in the absence of more sensitive or infallible indicators, the most reasonable approach seems to evaluate them jointly.

CONCLUSION

It is important to underline the necessity of nutritional screening and the subsequent introduction of adequate therapy while awaiting transplantation in an attempt to improve results. Considering the complexity of surgical procedures and the severity of underlying diseases with their intense metabolic components, the patient's nutritional status seems to significantly influence results. Consequently, nutritional risk assessments should be a part of the routine care of patients qualified for transplantation.

Body composition and risk factors for cardiovascular disease in global multi-ethnic populations

BACKGROUND

No large-scale studies have compared associations between body composition and cardiovascular risk factors across multi-ethnic populations.

METHODS

Population-based surveys included 30,721 Malay, 10,865 Indian and 25,296 Chinese adults from The Malaysian Cohort, and 413,737 White adults from UK Biobank. Sex-specific linear regression models estimated associations of anthropometry and body composition (body mass index [BMI], waist circumference [WC], fat mass, appendicular lean mass) with systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDL-C), triglycerides and HbA1c.

RESULTS

Compared to Malay and Indian participants, Chinese adults had lower BMI and fat mass while White participants were taller with more appendicular lean mass. For BMI and fat mass, positive associations with SBP and HbA1c were strongest among the Chinese and Malay and weaker in White participants. Associations with triglycerides were considerably weaker in those of Indian ethnicity (eg 0.09 [0.02] mmol/L per 5 kg/m2 BMI in men, vs 0.38 [0.02] in Chinese). For appendicular lean mass, there were weak associations among men; but stronger positive associations with SBP, triglycerides, and HbA1c, and inverse associations with LDL-C, among Malay and Indian women. Associations between WC and risk factors were generally strongest in Chinese and weakest in Indian ethnicities, although this pattern was reversed for HbA1c.

CONCLUSION

There were distinct patterns of adiposity and body composition and cardiovascular risk factors across ethnic groups. We need to better understand the mechanisms relating body composition with cardiovascular risk to attenuate the increasing global burden of obesity-related disease.

Exploring Handgrip Strength as a Cross-cultural Correlate of Body Composition and Upper Body Strength in Older Adults from Costa Rica and Kansas

Sarcopenia and disability in older adults are often characterized by body composition measurements; however, the gold standard of body composition measurement, dual-energy X-ray absorptiometry (DEXA), is expensive to acquire and maintain, making its use in low and middle income countries (LMIC) it out-of-reach in developing nations. Because these LMIC will bear a disproportionate amount of chronic disease burden due to global aging trends, it is important that reliable, low-cost surrogates need to be developed. Handgrip strength (HGS) is a reliable measure of disability in older adults but has not been used widely in diverse populations. This study compared HGS to multiple measurements of body composition in older adults from the US (Kansas) and a middle-income country (Costa Rica) to test if HGS is a cross-culturally appropriate predictive measure that yields reliable estimates across developed and developing nations. Percent body fat (%BF), lean tissue mass index (LTMI), appendicular lean soft tissue index (ALSTI), body fat mass index (BFMI), bone mineral density (BMD), and HGS were measured in older Costa Ricans (n = 78) and Kansans (n = 100). HGS predicted lean arm mass with equal accuracy for both samples (p ≤ 0.05 for all groups), indicating that it is a reliable, low-cost and widely available estimate of upper body lean muscle mass. Older adults from Costa Rica showed different body composition overall and HGS than controls from Kansas. Handgrip operates equivalently in the US and Mesoamerica and is a valid estimate of lean arm muscle mass as derived by the more expensive DEXA.

Temporal trends in obesity defined by the relative fat mass (RFM) index among adults in the United States from 1999 to 2020: a population-based study

OBJECTIVES

The body mass index (BMI) largely underestimates excess body fat, suggesting that the prevalence of obesity could be underestimated. Biologically, women are known to have higher body fat than men. This study aimed to compare the temporal trends in general obesity by sex, ethnicity and age among adults in the USA using the relative fat mass (RFM), a validated surrogate for whole-body fat percentage and BMI.

DESIGN

Population-based study.

SETTING

US National Health and Nutrition Examination Survey, from 1999-2000 to 2017-March 2020.

PARTICIPANTS

A representative sample of adults 20-79 years in the USA.

MAIN OUTCOME MEASURES

Age-adjusted prevalence of general obesity. RFM-defined obesity was diagnosed using validated cut-offs to predict all-cause mortality: RFM≥40% for women and ≥30% for men. BMI-defined obesity was diagnosed using a cut-off of 30 kg/m2.

RESULTS

Analysis included data from 47 667 adults. Among women, RFM-defined obesity prevalence was 64.7% (95% CI 62.1% to 67.3%) in 2017-2020, a linear increase of 13.9 percentage points (95% CI 9.0% to 18.9%; p<0.001) relative to 1999-2000. In contrast, the prevalence of BMI-defined obesity was 42.2% (95% CI 39.4% to 45.0%) in 2017-2020. Among men, the corresponding RFM-defined obesity prevalence was 45.8% (95% CI 42.0% to 49.7%), a linear increase of 12.0 percentage points (95% CI 6.6% to 17.3%; p<0.001). In contrast, the prevalence of BMI-defined obesity was 42.0 (95% CI 37.8% to 46.3%). The highest prevalence of RFM-defined obesity across years was observed in older adults (60-79 years) and Mexican Americans, in women and men. Conversely, the highest prevalence of BMI-defined obesity across years was observed in middle-age (40-59 years) and older adults, and in African American women.

CONCLUSIONS

The use of a surrogate for whole-body fat percentage revealed a much higher prevalence of general obesity in the USA from 1999 to 2020, particularly among women, than that estimated using BMI, and detected a disproportionate higher prevalence of general obesity in older adults and Mexican Americans.

The Role of BIA Analysis in Osteoporosis Risk Development: Hierarchical Clustering Approach

Osteoporosis is a common musculoskeletal disorder among the elderly and a chronic condition which, like many other chronic conditions, requires long-term clinical management. It is caused by many factors, including lifestyle and obesity. Bioelectrical impedance analysis (BIA) is a method to estimate body composition based on a weak electric current flow through the body. The measured voltage is used to calculate body bioelectrical impedance, divided into resistance and reactance, which can be used to estimate body parameters such as total body water (TBW), fat-free mass (FFM), fat mass (FM), and muscle mass (MM). This study aims to find the tendency of osteoporosis in obese subjects, presenting a method based on hierarchical clustering, which, using BIA parameters, can group patients who show homogeneous characteristics. Grouping similar patients into clusters can be helpful in the field of medicine to identify disorders, pathologies, or more generally, characteristics of significant importance. Another added value of the clustering process is the possibility to define cluster prototypes, i.e., imaginary patients who represent models of "states", which can be used together with clustering results to identify subjects with similar characteristics in a classification context. The results show that hierarchical clustering is a method that can be used to provide the detection of states and, consequently, supply a more personalized medicine approach. In addition, this method allowed us to elect BIA as a potential prognostic and diagnostic instrument in osteoporosis risk development.

Frequency and Functional Consequences of Low Appendicular Lean Mass and Sarcopenic Obesity in Patients with Asthma Referred for Pulmonary Rehabilitation

INTRODUCTION

One of the most prominent extrapulmonary manifestations in patients with chronic respiratory disease is changes in body weight and composition. However, the frequency and functional consequences of low appendicular lean mass (ALM) or sarcopenic obesity (SO) in patients with asthma are largely unknown. Therefore, the aim of the current study was to assess the frequency and functional consequences of low appendicular lean mass index (ALMI) and SO in patients with asthma.

METHODS

A retrospectively analyzed cross-sectional study was conducted in 687 patients with asthma (60% female, 58 ± 13 years, FEV1 76 ± 25% pred) referred for comprehensive pulmonary rehabilitation (PR). Body composition, pulmonary function, exercise capacity, quadriceps muscle function, and quality of life were assessed. Patients were classified as presenting low ALMI according to the 10th percentiles of age-sex-body mass index (BMI)-specific reference values and as having SO according to the diagnostic procedure proposed by the 2022 ESPEN/EASO consensus. In addition, clinical outcomes between patients with normal and low ALMI or with and without SO were compared.

RESULTS

The frequency of patients classified as low ALMI was 19%, whereas 45% of the patients were obese. Among the obese patients, 29% had SO. In patients with normal weight, those with low ALMI were younger and had worse pulmonary function, exercise capacity and quadriceps muscle function than those with normal ALMI (all p < 0.05). Overweight patients with low ALMI presented poorer pulmonary function and quadriceps muscle function (both strength and total work capacity). In obese class I patients, those with low ALMI showed lower quadriceps strength and maximal oxygen uptake acquired during cardiopulmonary exercise testing. Both male and female patients with SO showed lower quadriceps muscle function and reduced maximal exercise capacity compared to non-SO asthma patients.

CONCLUSION

Approximately one in five asthma patients presented low ALM when age-sex-BMI-specific ALMI cutoffs were applied. Obesity is common among patients with asthma referred for PR. Among the obese patients, a significant proportion presented SO. Low ALM and SO were associated with worse functional outcomes.

[Assessment of low muscle mass and strength in a control population]

Introduction

Background and aims: low muscle mass (LMM) conditions the nutritional status of an individual and has implications for quality of life and prognosis. The aim of this study was to evaluate body composition and determine normal values in the diagnosis of LMM in a control group of healthy individuals. Methods: a cross-sectional study of healthy volunteers aged 18 to 45 years with body mass index (BMI) < 30 kg/m2. A descriptive study was performed including demographic, clinical, anthropometric, and body composition variables (by bioimpedance, TANITA MC 780 MA; TANITA, Tokyo, Japan), stratified by age, sex and BMI. Values corresponding to -1/-2 standard deviations (SD) were determined to consider low muscle mass/function. Results: we included 67 patients, 71,60 % women, with a median age of 28.29 (IQR 4.05) years. Males presented higher weight, BMI, fat-free mass (FFM), muscle mass (MM), appendicular lean mass (ALM), appendicular lean mass index (ALMI), and dynamometry values when compared to females. The -1/-2 SD values of the various muscle parameters were determined according to sex. Conclusion: this study determined normal LMM values in healthy and young people, and the most commonly used indexes to express it, which will allow the diagnosis of LMM in disease-related situations using the corresponding -2 DS value.

Optimal body composition indices cutoff values based on all-cause mortality in the elderly

The cutoffs of body composition indices are inconclusive in older populations. This study is designed toward determining the optimal cutoffs of the body composition indices based on the association with all-cause mortality. During 2009 and 2010, a cohort population of 1200 was enrolled in central western Taiwan. Of the 1200 subjects, 428 older subjects (mean age: 72.5 ± 5.4 yrs.; 47.7 % were women) were censored in this study. The waist circumference (WC) and body mass index (BMI) were measured using standard anthropometric methods. A multi-frequency bioelectrical impedance analysis device was utilized to estimate each participant's body composition indices, including percent body fat (PBF) and skeletal muscle mass index (SMMI). All claims records of death from 2009 to 2018 in the National Health Insurance Research Databank were identified. A receiver operating characteristic curve method and the highest Youden index were used to identify the optimal cutoffs. A Cox proportional hazards regression analysis was used to model associations between each of the recommended cutoff values with all-cause mortality. The all-cause mortality rate was 20.09 % after a follow-up period of 5.86 ± 2.39 person-years. The significant indices cutoff value was identified to be WC (86.7 cm) for older women and BMI (23.8 kg/m²) and as WC (77.6 cm), and SMMI (8.7 kg/m²) for older men. The recommended optimal cutoffs of the body composition indices were gender-specific and can be utilized to predict the risk of all-cause mortality.

Sensitivity and Specificity of Anthropometric Indices in Identifying Obesity in Women over 40 Years of Age and Their Variability in Subsequent Decades of Life

Anthropometric measurements and indices are a simple and inexpensive method to assess normal physical development and quickly identify the risk of diseases. The aim of the study was to verify the sensitivity (Se) and specificity (Sp) of selected anthropometric indices in a group of women over 40 years. The study included 87 women (group I-40 to 49 years, group II-50 to 59 years, group III-60 to 69 years, and group IV-70 to 79 years). Anthropometric characteristics were measured: body mass (BM), body height (BH), waist circumference (WC), and hip circumference (HC). Body mass index (BMI), body adiposity index (BAI), waist-hip ratio (WHR), and waist-to-height ratio (WHTR) were calculated. The percentage of fat tissue (FT) and visceral fat volume (FV) were evaluated using DEXA. A decrease in mean BH with an increase in the mean WC, WHR, and WHTR in subsequent decades. There were strong statistically significant correlations between FT and most indicators (except for WHR). FV was correlated at a strong or moderate level with most parameters. In the group of women aged 40 to 80 years, the most favorable AUC was obtained for WC, followed by BMI. BAI can be recommended as a complementary indicator to BMI.

Influence of reduced muscle mass and quality on ventilator weaning and complications during intensive care unit stay in COVID-19 patients

BACKGROUND & AIMS

Sarcopenia, a loss of muscle mass, quality and function, which is particularly evident in respiratory muscles, has been associated with many clinical adverse outcomes. In this study, we aimed at evaluating the role of reduced muscle mass and quality in predicting ventilation weaning, complications, length of intensive care unit (ICU) and of hospital stay and mortality in patients admitted to ICU for SARS-CoV-2-related pneumonia.

METHODS

This was an observational study based on a review of medical records of all adult patients admitted to the ICU of a tertiary hospital in Milan and intubated for SARS-CoV-2-related pneumonia during the first wave of the COVID-19 pandemic. Muscle mass and quality measurement were retrieved from routine thoracic CT scans, when sections passing through the first, second or third lumbar vertebra were available.

RESULTS

A total of 81 patients were enrolled. Muscle mass was associated with successful extubation (OR 1.02, 95% C.I. 1.00-1.03, p = 0.017), shorter ICU stay (OR 0.97, 95% C.I. 0.95-0.99, p = 0.03) and decreased hospital mortality (HR 0.98, 95% C.I. 0.96-0.99, p = 0.02). Muscle density was associated with successful extubation (OR 1.07, 95% C.I. 1.01-1.14; p = 0.02) and had an inverse association with the number of complications in ICU (Β -0.07, 95% C.I. -0.13 - -0.002, p = 0.03), length of hospitalization (Β -1.36, 95% C.I. -2.21 - -0.51, p = 0.002) and in-hospital mortality (HR 0.88, 95% C.I. 0.78-0.99, p = 0.046).

CONCLUSIONS

Leveraging routine CT imaging to measure muscle mass and quality might constitute a simple, inexpensive and powerful tool to predict survival and disease course in patients with COVID-19. Preserving muscle mass during hospitalisation might have an adjuvant role in facilitating remission from COVID-19.

Body composition reference values in Singaporean adults using dual-energy X-ray absorptiometry-The Yishun study

OBJECTIVES

This study establishes age- and sex-specific reference values for fat mass index (FMI), lean mass index (LMI), appendicular LMI (aLMI), and body fat distribution indices including Android/Gynoid % fat ratio and Trunk/Limb % fat ratio in multi-ethnic Singaporean adults.

METHODS

A population-based cross-sectional study using dual-energy X-ray absorptiometry (Hologic Discovery Wi) was carried out to measure whole body and regional fat and lean mass in community-dwelling adults. A total of 537 adults (57.5% women), aged from 21 to 90 years, were recruited from the large north-eastern residential town of Yishun. Age- and sex-specific percentile reference values were generated for FMI, LMI, aLMI, Android/Gynoid % fat ratio and Trunk/Limb % fat ratio using the Lambda-Mu-Sigma method. The relationship between the parameters and age were assessed through the Pearson's correlation coefficient.

RESULTS

All parameters demonstrated significant correlation with age (p < 0.05) for both men and women, except for LMI in women, with the strength of r ranging from 0.12 (weak correlation) to 0.54 (strong correlation). LMI (r = -0.45) and appendicular LMI (r = -0.54) were negatively associated with age in men while none (r = -0.06) to weak correlation (r = -0.14) were shown in women for the same parameters respectively. The Android/Gynoid % fat ratio and Trunk/Limb % fat ratio were positively related to age for both men (r = 0.37 & 0.43, p < 0.001) and women (r = 0.52 & 0.48, p < 0.001).

CONCLUSION

We have established DXA-based body composition reference data for the Singapore adult population. These reference data will be particularly useful in geriatric, obesity and oncology clinics, enabling the prescription of appropriate therapy to individuals at risk of morbidity from unfavorable body composition phenotypes. It also adds on to the limited reference database on Southeast Asian body composition.

The Use of Different Anthropometric Indices to Assess the Body Composition of Young Women in Relation to the Incidence of Obesity, Sarcopenia and the Premature Mortality Risk

The objective of the study was to evaluate the stratification of young women based on the assessment of body composition according to several currently recommended anthropometric indices and parameters, as well as the presence of obesity, sarcopenic obesity and the risk of premature death. Three hundred and three young Caucasian women aged 18-25 years were included in the cross-sectional observational study. For the purposes of the study, we used the bioelectrical impedance method and applied the obtained data to calculate indices defining obesity, sarcopenic obesity and premature mortality risk (ABSI z-score). We found significant differences between indicators of total and abdominal obesity when determining the rate of risk of premature death and diagnosis of obesity. Our results also suggest that FMI and FM/FFM indices correlate excellently with fat mass and visceral adipose tissue, better than BMI. Even in the case of abdominal obesity, FMI appears to correlate relatively strongly, more so than BMI. The results of the study support the opinion that in the assessment of body composition and health status, the presence of obesity (sarcopenic obesity) and the risk of premature death, anthropometric parameters and indices focusing not only on body weight (BMI, ABSI), but also on the proportionality and distribution of fat (WC, WHR, WHtR, VFA) and muscle tissue (FFMI, SMMI, FM/FFM ratio) should be used.

Is predicted body-composition and relative fat mass an alternative to body-mass index and waist circumference for disease risk estimation?

BACKGROUND AND AIMS

New methods to estimate body-composition have recently been proposed, but their relation to diseases, such as diabetes and coronary heart disease, needs further investigation. The purpose of this study was to investigate the association between proposed prediction of body-composition (PBC); Relative Fat Mass (RFM), Body Mass Index (BMI), Waist Circumference (WC) and disease.

METHODS

In a cross-sectional cohort (NHANES) the association between the four body measures and diabetes, high blood pressure, coronary heart disease, cancer, arthritis, and hospitalization were assessed. A total of 13,348 people was included in this study. Receiver operating characteristic (ROC), Area Under Curve (AUC) and statistical testing were used to evaluate the differences.

RESULTS

PBC/RFM had significant higher AUC than BMI or WC for diabetes, high blood pressure, hospitalization, and arthritis. PBC had a significant higher AUC than RFM, BMI, WC for Cancer and coronary heart disease.

CONCLUSIONS

RFM and PBC could be a better indicator to distinguish amongst people with a risk of diseases compared to traditional measures such as BMI and WC. However, future studies need to investigate the longitudinal association between RFM, PBC and the risk of disease development to assess if these measures are better suited for risk-stratification.

Sarcopenia Is a Cause and Consequence of Metabolic Dysregulation in Aging Humans: Effects of Gut Dysbiosis, Glucose Dysregulation, Diet and Lifestyle

Skeletal muscle mass plays a critical role in a healthy lifespan by helping to regulate glucose homeostasis. As seen in sarcopenia, decreased skeletal muscle mass impairs glucose homeostasis, but it may also be caused by glucose dysregulation. Gut microbiota modulates lipopolysaccharide (LPS) production, short-chain fatty acids (SCFA), and various metabolites that affect the host metabolism, including skeletal muscle tissues, and may have a role in the sarcopenia etiology. Here, we aimed to review the relationship between skeletal muscle mass, glucose homeostasis, and gut microbiota, and the effect of consuming probiotics and prebiotics on the development and pathological consequences of sarcopenia in the aging human population. This review includes discussions about the effects of glucose metabolism and gut microbiota on skeletal muscle mass and sarcopenia and the interaction of dietary intake, physical activity, and gut microbiome to influence sarcopenia through modulating the gut–muscle axis. Emerging evidence suggests that the microbiome can regulate both skeletal muscle mass and function, in part through modulating the metabolisms of short-chain fatty acids and branch-chain amino acids that might act directly on muscle in humans or indirectly through the brain and liver. Dietary factors such as fats, proteins, and indigestible carbohydrates and lifestyle interventions such as exercise, smoking, and alcohol intake can both help and hinder the putative gut–muscle axis. The evidence presented in this review suggests that loss of muscle mass and function are not an inevitable consequence of the aging process, and that dietary and lifestyle interventions may prevent or delay sarcopenia.

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.

Using Body Composition Groups to Identify Children and Adolescents at Risk of Dyslipidemia

The impact of body composition on the early origin of chronic diseases is an increasingly appreciated phenomenon. Little is known about the characteristics of children with varying body composition. The aim of this study was to investigate serum lipid profiles and other characteristics in relation to body composition. The data of 1394 participants (aged 6 to <18 years) of the observational general population-based Austrian LEAD Study have been analyzed. Body composition groups were defined by appendicular lean mass (ALMI) and fat mass (FMI) indices assessed by DXA. Serum lipid profiles (triglycerides, LDL-c, HDL-c) and other characteristics (e.g., prematurity, smoke exposure, physical activity, nutrition) were investigated in these body composition groups. Different body composition groups, which are not distinguishable by BMI, exist. Children with high ALMI and high FMI showed higher triglycerides and LDL-c, but lower HDL-c levels. In contrast, levels did not differ between those with high FMI but low (or normal) ALMI, and other body composition groups. BMI should be interpreted cautiously, and body composition should be measured by more precise techniques. In particular, children and adolescents with high FMI who have concomitantly high ALMI should be followed closely in future studies to investigate whether they are at increased risk of cardiovascular problems.

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.

Sex difference of mortality by age and body mass index in gastric cancer

Mortality difference by age, sex, body mass index (BMI) in gastric cancer (GC) has been controversial. We evaluated sex-specific mortality by age and BMI. A total of 5961 patients diagnosed with GC from 2005 to 2013 in a single tertiary center were included and were followed until December 2017. The plot in goodness-of-fit-test by sex was crossed, so we performed sex-specific analysis. Overall mortality was lower in women than in men (adjusted hazard ratio [aHR], 0.72). Favor outcomes in women compared to men were observed among patients older than 60 yr (aHR, 0.64; 95% CI, 0.56-0.74), a BMI less than 25 kg/m² (aHR, 0.69; 95% CI, 0.61-0.79), and stage I (aHR, 0.46; 95% CI, 0.38-0.56). In sex-specific analysis, mortality increased in age older than 60 yr in men, whereas it increased in both extreme ages (<40 yr and ≥ 70 yr) in women. Mortality by BMI was lowest at BMI of 25-29.9 kg/m² and gradually increased according to decrease of BMI in men; aHR, 1.24 (23-24.9 kg/m²), 1.44 (18.5-22.9 kg/m²), and 2.54 (BMI<18.5 kg/m²). However, mortality decreased in patients with BMI ≥ 30 kg/m² (aHR, 0.46) in women. The sex discrepancies in GC mortality by age and BMI suggest the need for sex-specific approaches to prognostic prediction.

Personalized Diet in Obesity: A Quasi-Experimental Study on Fat Mass and Fat-Free Mass Changes

Considering that the prevalence of overweight and obesity in Southeast of Spain is high, the aim of this work was to analyze the relation between the adherence to a personalized diet and the effectiveness of changes in the body composition in overweight and obese adults in this region. This quasi-experimental study presents the following selection criteria: attendance at the consultation between 2006 and 2012, subjects ≥ 19 years of age with overweight or obesity. In total, 591 overweight or obese individuals were involved in this study, attending 4091 clinic consultations in total. Most of the sample consisted of subjects who attended >3 consultations (>1.5 months), and were females aged 19-64 years who obtained clinically significant changes in fat mass (FM, ≥5%) and recommended changes in fat-free mass (FFM, ≥0%). Based on the results obtained and the experience gained from this research, the following recommendations are established: (i) record fat mass and fat-free mass index as a complement to body mass index; (ii) use FM and FFM to evaluate effectiveness of interventions with the aim of obtaining body composition changes; (iii) use personalized diet to achieve significant changes in FM and avoid non-recommended changes in FFM.

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.

Body composition assessment using bioelectrical impedance analysis (BIA) in a wide cohort of patients affected with mild to severe obesity

BACKGROUND & AIMS

Obesity is characterized by fat mass excess (FM), extra cellular water increase (ECW) and, with ageing, decrease in fat free mass (FFM). The validity of body impedance analysis (BIA) in patients with mild to severe obesity is still debated. The purpose of this study is to describe the Resistance (Rz) and Reactance (Xc) values obtained by Body Impedance Analysis (BIA) in a wide cohort of Italian patients with mild to severe obesity. The secondary endpoint is to describe the resulting body composition values (as percentage and indexes) in this population.

METHODS

The study enrolled adult in-patients with mild to severe obesity (classified with class I, II and III obesity) undergoing clinical care rehabilitation program for obesity complications and weight loss. BIA values were grouped by sex, BMI and age classes.

RESULTS

A total of 8303 patients with obesity, aged 18 to 90 y, were studied. The Resistance (Rz) and Reactance (Xc) were reported by sex, age and BMI classes. In women and men both, the phase angle (PhA) decreases with increasing BMI (kg/m²) and the resulting BIA vector was significantly shifted. The FM index (FMI) was higher (p < 0.0001) in women while FFM index (FFMI) was higher in men (p < 0.0001) and significantly associated with BMI. FFMI decreased with age in both sex (p < 0.0001). Skeletal mass (SM) presents a progressive reduction in relation to age and gender both.

CONCLUSIONS

The present BIA-based body composition analysis in a wide cohort of mild to severe obese patients revealed a significantly decreased Rz and Xc values with a consequent significant decrease of PhA in a BMI-dependent manner. The body compartments estimation with available equations was BMI, sex and age dependent. These observational results could be the basis for the development of new equations adapted for patients suffering from obesity.

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.

Body Composition Methods in Adults with Type 2 Diabetes or at Risk for T2D: a Clinical Review

PURPOSE OF REVIEW

The aim of this study is to summarize anthropometric and advanced methods used to assess body composition in adults diagnosed with type 2 diabetes (T2D) or at risk for T2D that provide clinically relevant information about T2D disease-related complications or risk factors.

RECENT FINDINGS

Anthropometry is commonly used in clinical settings; however, provides unreliable estimates of fat mass, fat-free mass, and body fat distribution for metabolic health assessments compared to advanced techniques such as bioelectrical impedance analysis (BIA), dual-energy x-ray absorptiometry (DXA), computerized tomography (CT), and magnetic resonance imaging (MRI). Few studies report the clinical use of anthropometric and advanced body composition methods that identify T2D disease-related complications or T2D risk factors. Anthropometry, BIA, DXA, CT, and MRI were used to estimate body adiposity and distribution, visceral and subcutaneous adipose tissue depots, and skeletal muscle mass. Review findings indicate that these methods were capable of identifying clinically relevant T2D disease-related complications such as sarcopenia and T2D risk factors such as obesity or regional adiposity. However, estimates were often sex and race/ethnicity specific warranting cross-validation of these methods in broader populations with T2D or risk for T2D prior to clinical implementation.

Diagnosis of obesity based on body composition-associated health risks-Time for a change in paradigm

Traditional diagnosis and understanding of the pathophysiology of obesity are based on excessive fat storage due to a chronically positive energy balance characterized by body mass index (BMI). Quantitative and qualitative analysis of lean and adipose tissue compartments by body composition analysis reveals that characterization of obesity as "overfat" does not facilitate a comprehensive understanding of obesity-associated health risk. Instead of being related to fat mass, body composition characteristics underlying BMI-associated prognosis may depend (i) on accelerated growth by a gain in lean mass or fat-free mass (FFM) in children with early BMI rebound or adolescents with early puberty; (ii) on a low muscle mass in aging, associated chronic disease, or severe illness; and (iii) on impaired adipose tissue expandability with respect to cardiometabolic risk. It is therefore time to call the adipocentric paradigm of obesity into question and to avoid the use of BMI and body fat percentage. By contrast, obesity should be seen in face of a limited FFM/muscle mass together with a limited capacity of fat storage.

Shifting perspectives – interplay between non-alcoholic fatty liver disease and insulin resistance in lean individuals

Non-alcoholic fatty liver disease (NAFLD) has become a significant public health burden affecting not only obese individuals but also people with normal weight. As opposed to previous beliefs, this particular subset of patients has an increased risk of all-cause mortality and worse outcomes than their obese counterparts. The development of NAFLD in lean subjects seems to be interconnected with metabolic phenotype, precisely visceral fat tissue, sarcopenia, and insulin resistance. Here, we summarize available data focusing on the co-dependent relationship between metabolic phenotype, insulin resistance, and development of NAFLD in lean individuals, suggesting more appropriate tools for measuring body fat distribution for the screening of patients at risk.

Reference charts for body composition parameters by dual-energy X-ray absorptiometry in European children and adolescents aged 6 to 18 years-Results from the Austrian LEAD (Lung, hEart, sociAl, boDy) cohort

BACKGROUND

DXA is a widely used technique to assess body composition. Reference values based on a large general population cohort of European children and adolescents were missing. The aim of this study was to provide age- and sex-specific reference percentiles of body composition parameters for European children and adolescents and to compare them to the American NHANES cohort. Additionally, exponents accounting best for height biases were analysed.

METHODS

DXA scans of 1573 participants, aged 6 to 18 years, recruited from 2011 to 2019 by the Austrian LEAD study, a representative population-based cohort, have been used to create reference charts using the LMS model.

RESULTS

Reference charts displaying percentile curves and the corresponding reference values are provided. Fat mass parameters were higher in females, while lean mass parameters were higher in males. Compared to the NHANES cohort medians of FMI and LMI were always lower. For FMI, BMI, LMI and ALMI the best fitting exponent were 2.5, 3, 3 and 3.5 respectively CONCLUSIONS: The present study provides reference charts for children and adolescents aged 6 to 18 years, for body composition parameters assessed by DXA. The charts enable comparison to a European general-population cohort and indicate that reference populations should be chosen with caution.

Body mass index and skeletal muscle index are useful prognostic factors for overall survival after gastrectomy for gastric cancer: Retrospective cohort study

Among patients undergoing gastrectomy for gastric cancer, the impact of anthropometric indices on surgical outcomes is not well-established. The aim of this study was to evaluate the prognostic significance of the skeletal muscle index (SMI) and body mass index (BMI) on overall survival (OS) in patients with gastric cancer.A total of 305 patients who underwent curative gastrectomy for gastric adenocarcinoma between January 2005 and March 2008 were enrolled. Patients were classified into groups based on the SMI and BMI. The SMI was measured by preoperative abdominal computed tomography (CT). The SMI groups were classified based on gender-specific cut-off values obtained by means of optimum stratification. BMI groups were divided according to the World Health Organization definition of obesity for Asians.The mean SMI was 58.2 cm/m and the mean BMI was 23.2 kg/m. One hundred fifteen (37.7%) patients had sarcopenia based on the diagnostic cut-off values (56.2 cm/m for men and 53.6 cm/m for women). Apart from gender, there were no significant differences in patient characteristics or surgical outcomes between the SMI groups. In the underweight group, tumor (T) stage, tumor-node-metastasis (TNM) stage, number of retrieved lymph nodes, D2 dissection, and hospital stay were significantly increased compared with the overweight/obese group. High and low BMI, and low SMI, were independent prognostic factors for OS (hazard ratio [HR] = 2.355, 1.736, and 1.607, respectively; P = .009, .023, and .033, respectively).SMI and BMI did not impact perioperative morbidity in patients undergoing gastrectomy for gastric cancer. Both SMI and BMI are useful prognostic factors for OS in gastric cancer patients after gastrectomy.

How reliable is BMI? Bioimpedance analysis of body composition in underweight, normal weight, overweight, and obese women

Background

The human body consists of water, proteins, lipids, carbohydrates, and minerals that build cells, tissues, and organs. In healthy people, the content of these molecules remains nearly constant. The body mass index (BMI) is commonly used to classify abnormal body composition among adults. According to the WHO, a high BMI is a major risk factor for many diseases. Bioelectrical impedance analysis is a commonly used method for assessing body composition in clinical practice and medical research.

Aims

The aim of this study was to identify the advantages and disadvantages of using BMI in diagnosis of underweight, overweight, and obesity, by comparing the value of the index with the values of body composition analysis parameters.

Methods

A total of 267 healthy women 18 to 35 years of age participated in this study. Bioelectrical impedance analysis was performed on all participants at the beginning of the experiment with an InBodyS10 device.

Results

In the BMI categories of overweight and obese, only women with excessive BFM were measured with BIA. The BMI category of normal body weight, apart from women with normal body composition, includes people with both deficient and excess body components, e.g., body fat or lean body mass. The BMI category of underweight includes women with different body compositions as well as people with excessive fat content.

Conclusions

The BMI is useful to provide a warning of excessive fat content in overweight and obese women, whereas among normal weight and underweight women, it may mask various types of body composition defects.

Electronic supplementary material

The online version of this article (10.1007/s11845-020-02403-3) contains supplementary material, which is available to authorized users.

What are the factors associated with sarcopenia-related variables in adult women with severe obesity?

BACKGROUND

Understanding the association between sarcopenia-related variables and several risk factors may help to implement interventions aimed at preventing its occurrence by reducing or controlling the identified risk factors. Although changes in body composition occur in both sexes, in women, muscle loss is accentuated due to decreased estrogen levels following menopause. This study aims to determine the factors associated with sarcopenia-related parameters in middle-aged women identified with class II/III obesity (body mass index [BMI] ≥ 35 kg/m2).

METHODS

The study included 104 women with severe obesity (40.23 ± 8.49 years) with an average body fat percentage of 52.45 ± 4.14%. Sarcopenia was assessed using total appendicular skeletal muscle mass (ASMM), appendicular skeletal muscle mass index (ASMMI), and appendicular skeletal muscle mass adjusted by BMI (ASMM/BMI) as evaluated using dual energy X-ray absorptiometry (DXA). Hand grip strength (HGS) and HGS adjusted by BMI (HGS/BMI) were evaluated using dynamometry. Functional performance was assessed using the walking speed test (WS). The explanatory variables were age, lifestyle, comorbidities, food consumption, and metabolic parameters. A multivariate linear regression was performed.

RESULTS

Factors associated with sarcopenia-related variables in 104 severely obese women with a mean BMI of 43.85 kg/m2 were as follows: ASMMI negatively correlated with serum levels of tetraiodothyronine (T4) and tobacco use; ASMM/BMI negatively correlated with age, serum T4 levels, and diabetes; ASMM negatively correlated with T4 serum levels and diabetes; HGS negatively correlated with age and hypercholesterolemia, and positively correlated with low-density lipoprotein cholesterol (LDL-c); HGS/BMI negatively correlated with age and hypercholesterolemia and positively correlated with LDL-c; and WS negatively correlated with hypothyroidism and diabetes.

CONCLUSION

In severely obese women, muscle mass and function were inversely associated with age, smoking status, endocrine parameters, hypercholesterolemia, and comorbidities such as diabetes. Thus, the results of this investigation are relevant in supporting the development of clinical interventions to aid in the prevention of sarcopenia in adult women with severe obesity.

In utero nutritional stress as a cause of obesity: Altered relationship between body fat, leptin levels and caloric intake in offspring into adulthood

AIMS

Emerging evidence suggests that during gestation the in utero environment programs metabolism and can increase risk of obesity in adult offspring. Our aim was to study how alterations in maternal diets during gestation might alter body weight evolution, circulating leptin levels and caloric intake in offspring, leading to changes in body composition.

MATERIALS AND METHODS

We fed gestating rats either a control diet (CD), high fat diet (HFD) or an isocaloric low protein diet (LPD), and examined the repercussions in offspring fed similar diets post-weaning on birth weight, body weight evolution, body composition, insulin sensitivity, glucose tolerance and in the relationship between plasma leptin concentration and caloric intake in offspring during growth and development.

KEY FINDS

Offspring from dams fed LPD maintained reduced body weight with greater % lean mass and consumed fewer calories despite having leptin levels similar to controls. On the other hand, offspring from dams fed a HFD were insulin resistant and maintained increased body weight and % fat mass, while consuming more calories than controls despite elevated leptin concentrations. Therefore the uterine environment, modulated primarily through maternal nutrition, modified the relationship between circulating leptin levels, body fat, and caloric intake in the offspring, and dams fed a HFD produced offspring with excess adiposity, insulin resistance, and leptin resistance into adulthood.

SIGNIFICANCE

Our data indicates that in utero environmental factors affected by maternal diet program alterations in the set point around which leptin regulates body weight in offspring into adulthood contributing to obesity.

Percentiles for body composition parameters based on computed tomography in patients with endometrial cancer

OBJECTIVES

The aim of this study was to provide the percentiles of distribution of body composition parameters according to cancer staging and body mass index (BMI) stratum, as well as to identify the contribution of age, BMI, and cancer staging in the variation of the different parameters of body composition in a population of patients with endometrial cancer.

METHODS

We enrolled 545 patients who had pretreatment computed tomography images, which were used to assess total skeletal muscle (SM); low- and high-radiodensity SM; visceral, subcutaneous, and intramuscular adipose tissue; and mean skeletal muscle radiodensity (SMD). All the body composition parameters were normalized by the square of the stature. They were then presented on average and at the 5th, 50th and 95th percentiles. The correlation of these parameters with age, BMI, and cancer stage was tested, and then a multiple linear regression analysis was performed. P ≤ 0.05 was accepted as statistically significant.

RESULTS

BMI was associated with body fat parameters and low-radiodensity SM index; cancer stage was associated with SM index, mean SMD, and high-radiodensity SM index.

CONCLUSION

This study provides age, stage, and BMI specific percentiles for body composition parameters, which allowed an in-depth interpretation of how such body compartments, especially the low/high SM sub-ranges, varies according to these stratification variables.

Effects of Extra Virgin Olive Oil (EVOO) and the Traditional Brazilian Diet on Sarcopenia in Severe Obesity: A Randomized Clinical Trial

BACKGROUND

Nutritional interventions may have positive effects on sarcopenia and body composition.

OBJECTIVE

to evaluate the effectiveness of extra virgin olive oil (EVOO) consumption and a healthy traditional Brazilian diet (DieTBra) on improving sarcopenia indicators and reducing total body fat in severe obesity.

METHODS

A randomized controlled trial registered at ClinicalTrials.gov (NCT02463435) conducted with 111 severely obese participants randomized into three treatment groups-(1) EVOO (52 mL/day), (2) DieTBra, (3) DieTBra + EVOO (52 mL/day)-for 12 weeks. Body composition was assessed by dual-energy X-ray absorptiometry and sarcopenia by walking speed and handgrip strength.

RESULTS

Significant reductions in total body fat (p = 0.041) and body weight (p = 0.003) were observed in the DieTBra group. In the DietBra + olive oil group there was also a significant reduction in body weight (0.001) compared to the olive oil-only group. ANCOVA analyses showed reductions in total body fat in the DieTBra (p = 0.016) and DieTBra + olive oil (p = 0.004) groups. Individuals in the DieTBra group had significant improvements in their walking speed (p = 0.042) and handgrip strength (p = 0.044).

CONCLUSIONS

DieTBra contributes to improvements in handgrip strength, walking speed, and total body fat in severely obese adults. The major study was registered at ClinicalTrials.gov (NCT02463435).

Reference values for skeletal muscle mass and fat mass measured by bioelectrical impedance in 390 565 UK adults

BACKGROUND

Loss of skeletal muscle mass (SMM) increases the risk of frailty and, together with excess fat mass (FM), is a risk factor for cardio-metabolic disease. However, use of body composition measurements in nutritional surveillance and routine clinical practice is limited by the lack of reference data. Our aim was to produce age-specific and sex-specific reference values for SMM and FM in the White ethnic adult population in the UK. Secondary objectives were to examine the tracking over time using a subsample of the population with repeated measures of body composition and to assess the validity of these reference values in different ethnic subgroups.

METHODS

We used data from segmental bioelectrical impedance analysis (BIA) in 390 565 participants, aged 40-69 years, in the UK Biobank, and data from dual-energy X-ray absorptiometry from n = 905 participants to validate the BIA measurements. SMM was calculated as the sum of the predicted muscle mass from the limbs. The LMS method was used to produce percentile curves for the SMM index (SMMI = SMM/height² ) and the FM index (FMI = FM/height² ). We investigated the validity of the White ethnic reference values by plotting z-scores (99.7% confidence interval) from Black and Asian groups to check if their confidence interval included zero. Longitudinal trajectories were predicted based on the baseline z-scores and the correlation between repeated measurements at follow-up.

RESULTS

The percentile curves show that SMMI declines in men from the age of 40, whereas in women, SMMI is more stable and decreases only slightly among women in the higher percentiles. FMI increases with age in both men and women. Women have higher FMI and lower SMMI than men in all age groups. The validity of the White-based reference values for non-White ethnic groups is poor. Longitudinal trajectories in body composition in the subsample of participants with a follow-up assessment show regression towards the mean in both men and women, with some evidence of declining SMMI only among men. The predicted 90% limits for the expected 5 year trajectories of SMMI and FMI can be used to identify people with unusual trajectories and in clinical practice to identify and track individuals at risk of excessive loss of SMM.

CONCLUSIONS

These body composition reference values developed from BIA in a middle/older-aged healthy White ethnic population in the UK could be used as a simple assessment tool for nutritional surveillance and to identify individuals with low SMMI or high FMI who may be at increased risk of disease and/or frailty.

Reference Values for Skeletal Muscle Mass - Current Concepts and Methodological Considerations

Assessment of a low skeletal muscle mass (SM) is important for diagnosis of ageing and disease-associated sarcopenia and is hindered by heterogeneous methods and terminologies that lead to differences in diagnostic criteria among studies and even among consensus definitions. The aim of this review was to analyze and summarize previously published cut-offs for SM applied in clinical and research settings and to facilitate comparison of results between studies. Multiple published reference values for discrepant parameters of SM were identified from 64 studies and the underlying methodological assumptions and limitations are compared including different concepts for normalization of SM for body size and fat mass (FM). Single computed tomography or magnetic resonance imaging images and appendicular lean soft tissue by dual X-ray absorptiometry (DXA) or bioelectrical impedance analysis (BIA) are taken as a valid substitute of total SM because they show a high correlation with results from whole body imaging in cross-sectional and longitudinal analyses. However, the random error of these methods limits the applicability of these substitutes in the assessment of individual cases and together with the systematic error limits the accurate detection of changes in SM. Adverse effects of obesity on muscle quality and function may lead to an underestimation of sarcopenia in obesity and may justify normalization of SM for FM. In conclusion, results for SM can only be compared with reference values using the same method, BIA- or DXA-device and an appropriate reference population. Limitations of proxies for total SM as well as normalization of SM for FM are important content-related issues that need to be considered in longitudinal studies, populations with obesity or older subjects.

Reference values of body composition parameters and visceral adipose tissue (VAT) by DXA in adults aged 18-81 years-results from the LEAD cohort

Background

Increasing attention has been drawn on the assessment of body composition phenotypes, since the distribution of soft tissue influences cardio-metabolic risk. Dual-energy X-ray absorptiometry (DXA) is a validated technique to assess body composition. European reference values from population-based cohorts are rare.

Aims

To provide age- and sex-related reference values of body composition parameters and visceral adipose tissue (VAT) mass, and for lean mass index (LMI) with regard to fat mass index (FMI) quantities and BMI categories.

Methods

GE-Lunar Prodigy DXA scans of 10.894 participants, aged 18–81 years, recruited from 2011 to 2019 by the Austrian LEAD study, a population-based cohort study, have been used to construct reference curves using the LMS method. Parameters assessed are FMI, LMI, appendicular LMI, fat mass ratios android/gynoid and trunk/limbs, and VAT.

Results

All lean mass and fat mass parameters indicating central fat accumulation were higher in men, whereas other fat mass indices were higher in women. LMI differed between each FMI subgroup (low vs. normal, low vs. high, normal vs. high), and BMI category in all ages and LMI increased with FMI and BMI classes. VAT mass was higher in men compared with women and increased across all age groups within both sexes.

Conclusion

The present study provides age- and sex-related reference values for European adults aged 18–81 years for body composition parameters and VAT mass for Lunar Prodigy DXA. In addition, this study reports LMI reference values with regard to fat mass quantities, showing a positive association with increasing FMI percentiles and BMI categories.