Lean Mass Index Research Articles

The associations of erythrocyte membrane polyunsaturated fatty acids with skeletal muscle loss: A prospective cohort study

Polyunsaturated fatty acids (PUFAs) may play a vital role in maintaining skeletal muscle mass in the aged population. This study investigated the longitudinal relationship between the concentrations of erythrocyte membrane PUFAs and age-related changes in skeletal muscle mass over an average 6.5 years of follow-up in a Chinese middle-aged and older adult population. A total of 1494 participants aged 57.4±4.7 years were included in this study. Skeletal muscle mass was determined using dual-energy X-ray absorptiometry. Per year percent changes in the skeletal muscle index (Δ% SMI), appendicular skeletal muscle index (Δ% ASMI), and total body lean mass index (Δ% TBLMI) from baseline were calculated. Concentrations of total and individual cis-n-3 and cis-n-6 PUFAs of the erythrocyte membrane were determined using gas-liquid chromatography. Fully adjusted linear regression models showed that per unit increases in the concentrations of C18:2 n-6, C20:4 n-6, C22:4 n-6, and total n-6 PUFAs resulted in increases of 0.022%-0.155% in the Δ% SMI (P for linearity: <0.001-0.006). Restricted cubic spline analysis revealed an inverted U-shaped relationship between the concentrations of C20:2 n-6, C22:5 n-3, C22:6 n-3, and total n-3 PUFAs and the Δ% SMI (P for non-linearity: <0.001-0.036). In addition, an inverted U-shaped curve was also detected for the relationships of the linoleic acid/α-linolenic acid ratio (P for non-linearity=0.010) and n-6/n-3 PUFA ratio (P for non-linearity=0.013) with the Δ% SMI, with the Δ% SMI peaking at respective ratios of 124.96 and 3.69. Similar associations were revealed by the Bayesian kernel machine regression model. No interaction effect was detected between the individual PUFAs for the Δ% SMI in the bivariate exposure-response analysis. Overall, similar results were observed for the Δ% ASMI and Δ% TBLMI. The associations between different individual PUFAs and age-related muscle loss in middle-aged and older adults may be different. Our results suggest that high concentrations of erythrocyte membrane n-6 PUFAs may be correlated with less skeletal muscle mass loss, whereas extremely high concentrations of n-3 PUFAs may be correlated with more muscle loss.

FRI051 Lean Mass And Fat Mass Across Different Age Groups In The Thai Population

Abstract Disclosure: N. Charoenngam: None. D. Theerakulpisut: None. D. Sribenjalak: None. C. Pongchaiyakul: None. Introduction: Lean mass and fat mass have been shown to influence the risks of cardio-metabolic disorders. While obesity is defined as body mass index (BMI) of more than 30 kg/m2 in White, Hispanic, and Black individuals and 25 kg/m2 in Asian individuals, the cut-off values for lean mass and fat mass in different populations are less well-defined as data on reference values of lean mass (LM) and fat mass (FM), especially in the Southeast Asians, are limited. In this study, we aimed to determine the normative values of LM and FM across different age groups in the Thai population. Methods: Male and female consecutive community-dwelling individuals aged 20 - 90 years were recruited from Srinagarind Hospital, Khon Kaen, Thailand between 2010 and 2015. LM and FM were measured using dual energy x-ray absorptiometry on a Lunar Prodigy bone densitometer (GE Healthcare, Madison, WI). Lean mass index (LMI) and fat mass index (FMI) were calculated [LMI = LM (kg)/height (m)2, FMI = FM (kg)/height (m)2]. Percentiles of each variable stratified by age and sex were calculated. SPSS version 27 (SPSS Inc., Chicago, IL) was used to perform statistical analysis. Results: A total of 832 individuals (334 males and 498 females) were included in the study. The mean ± SD age, LM, FM, LMI and FMI were 50.0 ± 16.2 years, 38.9 ± 8.0 kg, 15.5 ± 7.7 kg, 15.6 ± 2.3 kg/m2 and 6.4 ± 3.3 kg/m2, respectively. In males, the median LM decreased from with age from 49.4 kg in 20 - 29 years group to 42.3 kg in ≥70 years group. The median LMI was relatively unchanged from age 20 - 59 years at 17.7 - 18.0 kg/m2 and dropped to 16.4 kg/m2 in ≥70 years group. The median FM and FMI increased with age from 6.3 kg and 2.5 kg/m2 in 20 - 29 years group to 11.9 kg and 4.6 kg/m2 in 60 - 69 years group and dropped to 10.3 kg and 4.1 kg/m2 in ≥70 years group. In females, the median LM peaked at age 30 - 39 years at 34.6 kg and decreased with age to 30.8 kg in ≥70 years group. The median LMI peaked at age 40 - 49 years at 14.6 kg/m2 and decreased with age to 13.8 kg/m2 in ≥70 years group. The median FM and FMI peaked at age 50 - 59 years at 20.7 kg and 9.0 kg/m2 and decreased with age to 15.9 kg and 7.1 kg/m2 in ≥70 years group. Conclusion: We generated age-stratified normative values of LM, FM, LMI and FMI from the cross-sectional data of community-dwelling Thai individuals. We observed that LM achieved its peak during early adulthood (age 20 - 29 years in males and 30 - 39 years in females) and decreased with older age. On the other hand, an inverse-U shaped association between FM and age was observed as FM achieved its peak at age 60 - 69 years in males and 50 - 59 in females and decreased with older age. Presentation: Friday, June 16, 2023

SAT382 Lean Mass and Associated Factors in Women with PCOS with Different Phenotypes

Abstract Disclosure: T.M. Fighera: None. B.R. Santos: None. P.M. Spritzer: None. Introduction: Obesity, insulin resistance and hyperandrogenism are common findings in women with PCOS. These abnormalities have been associated with muscle mass changes reported in previous studies, with conflicting results comparing women with PCOS versus non-PCOS controls. The aim of the present study was to evaluate clinical and laboratory variables related to lean body mass according to PCOS phenotype. METHODS: In this case-control study, we analyzed 133 women of reproductive age, recruited through public advertisement at the outpatient clinic of a University Hospital. Inclusion criteria were body mass index (BMI) ranging from 18.5 to 39.9 kg/m², age between 17 and 35 years and no intake of drugs known to interfere with hormone levels for at least 3 months before the study. Women with diabetes, thyroid dysfunction, liver or renal disease were excluded. PCOS was defined according to the Rotterdam Consensus. The study protocol was approved by the local Ethics Committee, and written informed consent was obtained from all participants. Blood pressure, BMI, body composition by dual-energy X-ray absorptiometry (DXA), and laboratory measurements for metabolic and hormonal variables were performed in all subjects. Creatinine values were used as an indirect marker of lean mass. RESULTS: Median age was 28 years (23-31), and the median BMI was 27.9kg/m² (24.1-33.7), with higher BMI in women with the AB phenotype of PCOS (n=59) compared to ovulatory (C phenotype) PCOS (n=23) and controls (n=51) (p=0.005). Women with the AB phenotype of PCOS presented higher Ferriman-Gallway score (p&amp;lt;0.001), systolic (p=0.001) and diastolic blood pressure (p=0.002), insulin levels (p=0.006), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) (p=0.008), metabolic syndrome prevalence (p&amp;lt;0.001), testosterone (p=0.008), free androgen index (FAI) (p&amp;lt;0.001), fat mass index (FMI) (0.015), and android-to-gynoid (AG) fat ratio (p=0.036) compared to controls. Appendicular lean mass index (ALMI) was higher in the AB phenotype than controls [7.01 (6.33-8.02) vs 6.69 (5.94-7.09), p= 0.024] and the C phenotype [6.60 (6.16-7.22), p=0.022]. A positive correlation was observed between ALMI and creatinine, even after adjustment to BMI, in women with AB phenotype (rho=0.319, p=0.023), but not with ovulatory PCOS (rho=0.293, p=0.238) or controls (rho=0.277, p=0.097). In a multivariate linear regression model, creatinine, HOMA-IR, and FMI were positively associated with ALMI, explaining 38.4% of the variation in lean mass. CONCLUSIONS: The present results suggest that the higher lean mass observed in women with the AB phenotype of PCOS is associated with hyperinsulinemia and higher fat mass. Sources of research support: INCT/CNPq and FAPERGS Presentation Date: Saturday, June 17, 2023

Lean mass and associated factors in women with PCOS with different phenotypes.

Although current evidence suggests increased risk of obesity, insulin resistance, and metabolic alterations in patients with polycystic ovary syndrome (PCOS), especially of a hyperandrogenic phenotype, the impact of each one of these variables on muscle mass remains uncertain. In this case-control study, we evaluated clinical and hormonal characteristics related to lean body mass according to the different PCOS phenotypes. We performed clinical, metabolic, and hormonal assessments and evaluated body compartments by dual-energy X-ray absorptiometry in 133 women of reproductive age. Creatinine served as an indirect marker of lean mass. Median age was 28 (range, 17-37) years. Women with phenotypes A and B (n = 59) had higher body mass index (BMI) and metabolic syndrome prevalence than those with phenotype C (n = 23) and controls (n = 51) (p<0.005). Women with phenotypes A and B also had higher Ferriman-Gallwey score (p<0.001), insulin levels (p = 0.006), HOMA-IR (p = 0.008), testosterone (p = 0.008), free androgen index (FAI) (p<0.001), fat mass index (FMI) (p = 0.015), android-to-gynoid fat ratio (p = 0.036), and bone mineral density (BMD) at lumbar spine (p = 0.027) and total femur (p = 0.013) than controls. Median appendicular lean mass index (ALMI) was higher in phenotypes A and B than in controls (7.01 [IQR, 6.33-8.02] vs. 6.69 [IQR, 5.94-7.09], p = 0.024), but it did not differ significantly from that in phenotype C (6.60 [IQR, 6.16-7.22], p = 0.222). Even after adjusting for BMI, ALMI correlated positively with creatinine in women with phenotypes A and B (rho = 0.319, p = 0.023) but not in those with phenotype C (p = 0.238) or controls (p = 0.097). In multivariate linear regression analyses, ALMI was positively associated with insulin, FAI, FMI, and total femur BMD. The present results suggest that fasting insulin, FAI, fat mass, and total femur BMD were positively associated with increased lean mass in women with PCOS phenotypes A and B.

Association of the amount of alcohol consumption with change in skeletal muscle and fat mass among Korean adults.

The association between changes in alcohol consumption and body composition remains unclear. We investigated the association between changes in drinking habits and muscle mass and fat mass in adults. From the Health Examinees in Korea, the study population (N=62094) was categorized according to alcohol consumption (g of ethanol/day) and the changes in drinking habits between the baseline and follow-up periods were determined. Predicted muscle mass index (pMM), lean mass index, and fat mass index (pFM) were also calculated using age, sex, weight, height, and waist circumference. The β coefficient and adjusted means were then calculated using multiple linear regression analysis after adjusting for covariates, including follow-up duration, calorie intake, and protein intake. Compared to the almost-unchanged drinking group (reference; adjusted mean:-0.030 [95% confidence intervals:-0.048,-0.011]), there was no statistical difference or tendency of change in the pMMs of the most-decreased (-0.024 [-0.048, 0.000]) and the most-increased (-0.027 [-0.059,-0.013]) alcohol-consumed groups. The pFM decreased at those with less alcohol consumption (0.053 [-0.011, 0.119]) and increased with increased alcohol consumption (0.125 [0.063, 0.187]), compared to the no-change group (reference; 0.088 [0.036, 0.140]). Thus, changes in alcohol consumption were not significantly associated with changes in muscle mass. Increased alcohol consumption was associated with increased fat mass. Reducing the amount of alcohol consumption may improve body composition in terms of fat mass.

Genetic Variants, Serum 25-Hydroxyvitamin D Levels, and Sarcopenia

Vitamin D deficiency is commonly associated with sarcopenia; however, the latest International Clinical Practice Guidelines for Sarcopenia do not recommend vitamin D supplementation for sarcopenia owing to a lack of an apparent therapeutic effect on the indices of sarcopenia among participants with replete vitamin D concentration (ie, 25-hydroxyvitamin D [25(OH)D] level >20 ng/mL) from randomized clinical trials. While there is consensus in all vitamin D guidelines that serum levels of 25(OH)D less than 10 ng/mL should be corrected, approximately 30% of the world population's 25(OH)D levels range from 10 to 20 ng/mL, and it remains unclear whether such suboptimal levels can maintain optimal health, including sarcopenia risk. To investigate the association of serum 25(OH)D level, especially suboptimal levels, with sarcopenia risk. This genome-wide genetic association study was performed from August 2022 to February 2023 among the 295 489 unrelated European participants from the UK Biobank (2006-2010). Nonlinear and standard mendelian randomization analyses were used to examine the association of serum 25(OH)D concentration with sarcopenia risk. A weighted genetic risk score using 35 unrelated single-nucleotide variants from the UK Biobank and weights from the SUNLIGHT Consortium was selected as an instrumental variable for serum 25(OH)D concentration. The primary outcome was sarcopenia, and the secondary outcomes consisted of grip strength, appendicular lean mass index, and gait speed. The final genetic analyses included 295 489 participants (mean [SD] age, 56.3 [8.1] years; 139 216 female [52.9%]). There was an L-shaped association between genetically predicted serum 25(OH)D concentration and sarcopenia risk. The risk of sarcopenia decreased rapidly as 25(OH)D concentration increased until 20 ng/mL and then leveled off. The odds ratio of sarcopenia for serum 25(OH)D level of 10 vs 20 ng/mL was 1.74 (95% CI, 1.17-2.59). Similar patterns were also observed when the association between serum 25(OH)D concentration and risks of each of the sarcopenia indices were evaluated. In this mendelian randomization genetic association study of adults in the UK Biobank, the findings supported a nonlinear association between suboptimal 25(OH)D levels and sarcopenia risk. Randomized clinical trials among participants with suboptimal 25(OH)D levels are required to verify the potential causality.

Reductions in Motor Unit Firing are Associated with Clinically Meaningful Leg Extensor Weakness in Older Adults.

Weakness, one of the key characteristics of sarcopenia, is a significant risk factor for functional limitations and disability in older adults. It has long been suspected that reductions in motor unit firing rates (MUFRs) are one of the mechanistic causes of age-related weakness. However, prior work has not investigated the extent to which MUFR is associated with clinically meaningful weakness in older adults. Forty-three community-dwelling older adults (mean: 75.4 ± 7.4years; 46.5% female) and 24 young adults (mean: 22.0 ± 1.8years; 58.3% female) performed torque matching tasks at varying submaximal intensities with their non-dominant leg extensors. Decomposed surface electromyographic recordings were used to quantify MUFRs from the vastus lateralis muscle. Computational modeling was subsequently used to independently predict how slowed MUFRs would negatively impact strength in older adults. Bivariate correlations between MUFRs and indices of lean mass, voluntary activation, and physical function/mobility were also assessed in older adults. Weak older adults (n = 14) exhibited an approximate 1.5 and 3Hz reduction in MUFR relative to non-weak older adults (n = 29) at 50% and 80% MVC, respectively. Older adults also exhibited an approximate 3Hz reduction in MUFR relative to young adults at 80% MVC only. Our model predicted that a 3Hz reduction in MUFR results in a strength decrement of 11-26%. Additionally, significant correlations were found between slower MUFRs and poorer neuromuscular quality, voluntary activation, chair rise time performance, and stair climb power (r's = 0.31 to 0.43). These findings provide evidence that slowed MUFRs are mechanistically linked with clinically meaningful leg extensor weakness in older adults.

Reference ranges for body composition indices by dual energy X-ray absorptiometry from the Bone Mineral Density in Childhood Study Cohort

BackgroundBody composition assessment aids evaluation of energy stores and the impact of diseases and interventions on child growth. Current United States pediatric reference ranges from the National Health and Nutrition Examination Survey (NHANES) include 20% of children with obesity, body mass index of ≥95th percentile. ObjectivesThis study aimed to develop dual energy X-ray absorptiometry (DXA) based reference ranges in a diverse cohort with low-obesity prevalence from the Bone Mineral Density in Childhood Study (BMDCS). MethodsThis is a secondary analysis of a longitudinal, prospective, observational cohort. Healthy children (height and BMI within 3rd to 97th percentiles, ages 5–19 y at enrollment), from 5 United States centers were measured annually for ≤7 visits. Whole body scans were acquired using Hologic scanners. A subsample underwent repeat measurements to determine precision. We generated reference ranges for appendicular and total lean soft tissue mass index (LSTM Index), fat mass index (FMI), and other body composition measures. Resulting curves were compared to NHANES and across subgroups. Sex and age-specific equations were developed to adjust body composition Z-scores for height Z score. ResultsWe obtained 9846 scans of 2011 participants (51% female, 22% Black, 17% Hispanic, 48% White, 7% Asian/Pacific Islander, and 6% with obesity). Precision (percent coefficient of variation) ranged from 0.7% to 1.96%. Median and–2 standard deviation curves for BMDCS and NHANES were similar, but NHANES +2 standard deviation LSTM Index and FMI curves were distinctly greater than the respective BMDCS curves. Subgroup differences were more extreme for appendicular LSTM Index-Z (mean ± SD: Asian −0.52 ± 0.93 compared with Black 0.77 ± 0.87) than for FMI-Z (Hispanic 0.29 ± 0.98 compared with Black −0.14 ± 1.1) and were smaller for Z-scores adjusted for height Z-score. ConclusionsThese reference ranges add to sparse normative data regarding body composition in children and adolescents and are based on a cohort with an obesity prevalence similar to current BMI charts. Awareness of subgroup differences aids in interpreting results.

Small for gestational age preterm infants and later adiposity and height: A systematic review and meta-analysis.

Overweight and obesity and their consequent morbidities are important worldwide health problems. Some research suggests excess adiposity origins may begin in fetal life, but unknown is whether this applies to infants born preterm. The objective of the study was to assess the association between small for gestational age (SGA) birth and later adiposity and height among those born preterm. MEDLINE, EMBASE and CINAHL until October 2022. Studies were included if they reported anthropometric (adiposity measures and height) outcomes for participants born preterm with SGA versus non-SGA. Screening, data extraction and risks of bias assessments were conducted in duplicate by two reviewers. We meta-analysed across studies using random-effects models and explored potential heterogeneity sources. Thirty-nine studies met the inclusion criteria. In later life, preterm SGA infants had a lower body mass index (-0.66 kg/m2 , 95% CI -0.79, -0.53; 32 studies, I2 = 16.7, n = 30,346), waist circumference (-1.20 cm, 95% CI -2.17, -0.23; 13 studies, I2 = 19.4, n = 2061), lean mass (-2.62 kg, 95% CI -3.45, 1.80; 7 studies, I2 = 0, n = 205) and height (-3.85 cm, 95% CI -4.73, -2.96; 26 studies, I2 = 52.6, n = 4174) compared with those preterm infants born non-SGA. There were no differences between preterm SGA and preterm non-SGA groups in waist/hip ratio, body fat, body fat per cent, truncal fat per cent, fat mass index or lean mass index, although power was limited for some analyses. Studies were rated at high risk of bias due to potential residual confounding and low risk of bias in other domains. Compared to their preterm non-SGA peers, preterm infants born SGA have lower BMI, waist circumference, lean body mass and height in later life. No differences in adiposity were observed between SGA preterm infants and non-SGA preterm infants.

Relationships Between Body Composition and Cognitive Impairment in Hospitalised Middle-Aged Type 2 Diabetic Patients.

The aim of this study was to elucidate the relationship between specific body composition and the risk of Cognitive Impairment (CI) in middle-aged Type 2 Diabetes Mellitus (T2DM) patients. This cross-sectional study included 504 hospitalized patients with T2DM from the Department of Endocrinology and Metabolism of the Tianjin Union Medical Center. Subjects were grouped by sex, and cognitive status was assessed using the Montreal Cognitive Assessment (MoCA). The relationship between body composition and cognitive ability was investigated with the use of linear regression analysis. The association between body composition and CI risk was determined by logistic regression analysis. The prevalence of CI was 39.3% in middle-aged T2DM patients. After adjusting for age, education, marriage status, carotid atherosclerosis, cerebrovascular disease and hemoglobin, multiple linear regression analysis showed that lean mass index (LMI), body mass index (BMI) and appendicular skeletal muscle index (SMI) were significant predictors for the MoCA scores in men (p < 0.05). In addition, BMI (OR 0.913, 95% CI 0.840-0.992) and LMI (OR 0.820, 95% CI 0.682-0.916) were independent protective factors for CI in males. After adjusted for age, education, marriage status, dietary control of diabetes and cerebrovascular disease, visceral obesity (VO, OR 1.950, 95% CI 1.033-3.684) and abdominal obesity (AO, OR 2.537, 95% CI 1.191-5.403) were risk factors for CI in female patients. The results suggest that there may be different mechanisms underlying the relationship of body compositions and cognitive performance between middle-aged male and female patients with T2DM. In addition, our finding of potential determinants of cognitive impairment may facilitate the development of intervention programs for middle-aged type 2 diabetic patients. Nevertheless, more large prospective studies looking at cognition and changes in body composition over time are needed in the future to further support their association.

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.

Phase angle as a key marker of muscular and bone quality in community-dwelling independent older adults: A cross-sectional exploratory pilot study

The aim of the present cross-sectional exploratory pilot study was to analyze the ability of the Phase Angle (PhA) to predict physical function, muscle strength and bone indicators, upon adjusting for potential confounders [age, sex, lean mass, and body mass index (BMI)]. This study included 56 physically independent older adults (age, 68.29 ± 3.01 years; BMI, 28.09 ± 4.37 kg/m2). A multi-frequency segmental bioelectrical impedance analysis was used to measure PhA at 50 KHz. Additionally, physical function was assessed through four functional capacity tests [30-sec chair‐stand; seated medicine ball throw (SMBT); timed up & go; and 6-min walking test (6 MWT)], muscle strength through the handgrip test (dominant side) and maximal isokinetic strength of the dominant knee flexor and extensor. Moreover, bone indicators and body composition were assessed through the dual energy X-ray absorptiometry.PhA was significantly associated with SMBT (r = 0.375, effect size (ES) = moderate); 6 MWT (r = 0.396, ES = moderate); 30-sec chair‐stand (rho = 0.314, ES = moderate); knee extension (rho = 0.566, ES = large) and flexion (r = 0.459, ES = moderate); handgrip (rho = 0.432, ES = moderate); whole-body bone mineral content (BMC) (r = 0.316, ES = moderate); femoral neck BMC (r = 0.469, ES = moderate); and femoral neck bone mineral density (BMD) (rho = 0.433, ES = moderate). Additionally, the results of multiple regression analysis demonstrated that PhA is significantly associated with SMBT (p < 0.001; R2 = 0.629), 6 MWT (p = 0.004; R2 = 0.214), knee extension (p < 0.001; R2 = 0.697), knee flexion (p < 0.001; R2 = 0.355), handgrip test (p < 0.001; R2 = 0.774), whole-body BMC (p < 0.001; R2 = 0.524), femoral neck BMC (p = 0.001; R2 = 0.249), and femoral neck BMD (p = 0.020; R2 = 0.153). The results of the preliminary analysis suggested that PhA is linked to muscle strength and some factors related to physical function and bone quality in community-dwelling older adults.

611-P: Direct and Indirect Pathways between Food Insecurity and Glycemic Control in Adults with Diabetes

Background: Extensive research has identified food insecurity as a driver of poor glycemic control in adults with diabetes. The goal of this study was to investigate the direct and indirect relationships between food insecurity and glycemic control, focusing on three possible pathways: body composition, anthropometrics, and healthy eating. Methods: Using national US data collected through the 2011-2018 National Health and Nutrition Examination Survey (NHANES), we created measures for body composition (total fat, total lean, fat mass index, lean mass index), anthropometrics (body mass index, waist circumference) and healthy eating index (food group component scores and overall HEI score). Food insecurity was scored based on the standard USDA scale, glycemic control was continuous HbA1c, and diabetes was based on self-report. Structural equation modeling using Stata v17 was used to investigate direct and indirect relationships in a sample of adults with diabetes. Total lean, waist circumference, and overall HEI score served as indicators for each of the three possible pathways based on preliminary correlations that found these as the strongest relationships for each category. Results: The final model was well fit (RMSEA=0.00, CFI=1.0, pclose 1.0) and showed higher food insecurity was directly associated with higher HbA1c (B=0.09, p&amp;lt;0.001) and indirectly associated through waist circumference and HEI score (B=0.008, p&amp;lt;0.001) in adults with diabetes. Food insecurity was significantly associated with higher waist circumference (B=0.07, p&amp;lt;0.001) and lower healthy eating (B=−0.09, p&amp;lt;0.05). Higher waist circumference (B=0.03, p&amp;lt;0.001) and lower healthy eating (B=−.06, p&amp;lt;0.05) were significantly associated with higher HbA1c. Body composition was not a significant pathway. Conclusions: Waist circumference and overall healthy eating index are significant pathways through which food insecurity is associated with worse glycemic control in adults with diabetes. Disclosure R.J.Walker: None. R.Amjad: None. L.E.Egede: None. Funding National Institutes of Health (R01DK118038, R01DK120861, R01MD013826)

PREVALENCE AND DETERMINANTS OF VASCULAR AGING IN AUSTRIA – A HOLISTIC VIEW: THE LEAD STUDY

Objective: Vascular aging (VA) is an important and prognostically relevant aspect of biological aging. Its determinants are incompletely understood, and a holistic view is missing. Design and method: The LEAD (Lung, Heart, Social, Body) study is an ongoing, longitudinal, population-based observational study, which started in 2011 in Vienna and six villages from Lower Austria. As part of the study, carotid-femoral pulse wave velocity (cfPWV) was measured non-invasively using applanation tonometry. In a predefined healthy normal population (non-smokers without known hypertension, diabetes, hyperlipidemia or cardiovascular disease, free from antihypertensive and lipid-lowering medication, blood pressure below 130/85 mmHg), age-specific Z-scores for cfPWV were calculated. Healthy (HVA), normal (NVA) and early (EVA) VA was defined as cfPWV value &lt; 10th, 10th-90th, and &gt;90th percentile, respectively. Results: In the overall population (n = 7924, 54.2% women, age 6-82 years), the prevalence of HVA/NVA/EVA was 7.3/70.3/22.4%, respectively, with EVA prevalence increasing in older age. NVA and EVA, as compared to HVA, were independently associated with age, hemodynamic parameters (blood pressure, heart rate), metabolic factors (diabetes), body composition (lean mass index), psychosocial (marital status), and socio-economic (socioeconomic status score, income, educational level) factors. Conclusions: In this large population-based study we observed a high percentage of early vascular aging in Austria. Besides age itself, hemodynamic factors and diabetes, body composition, psychosocial and socio-economic factors play an independent role in vascular aging. Cardiovascular prevention clearly needs to be improved and should be targeted towards high blood pressure on the one hand, but be holistically oriented on the other side.

Associated factors with hypertension, known poorly controlled hypertension, and newly diagnosed hypertension among people aged 18-70 in Senegal.

In this study, we aimed to determine the factors associated with hypertension, known poorly controlled hypertension, and newly diagnosed hypertension in 2015 to improve the prevention of this pathology in our country. This was a secondary analysis of the national WHO STEPwise survey database. It had a quantitative, descriptive, and analytical aim. The sampling was done in stratification in three stages of sampling. Statistical analysis was performed using Rstudio 4.0.2 software. It was a descriptive, bivariate, and multivariate analysis using binomial logistic regression for explanatory purposes. The risk factors for being hypertensive among 18-70- year-olds in Senegal in 2015 were: having taken their blood pressure at least once in their life; having taken their cholesterol levels at least once in their life; having received advice to reduce salt consumption; having received advice on how to reduce the amount of sugar; having a lean body mass index; being overweight; being obese III; and being between 35-39 and 65-70 years old. The protective factors are: checking the salt content indicated on the labels; and consuming salt-rich dishes "often" compared to "never". The risk factors for being newly diagnosed with hypertension among 18-70-year-olds in Senegal in 2015 were: having a history of stroke; having a resting heart rate greater than 80 beats per minute; consuming palm oil; and having high fasting blood sugar. The protective factors are: having a high average number of meals eaten per week not prepared at home; checking the salt content indicated on the label; and being of female sex. The risk factors for being known to have poorly controlled hypertension among 18-70- year-olds in Senegal in 2015 were: judging their reduction in salt consumption as "very important"; and having received advice to reduce their salt consumption. The protective factors are: performing physical activity only when traveling; and limiting the consumption of salty meals. Senegalese family cooking exposes to hypertension, small actions limiting salt consumption strongly protect against hypertension, and simple physical activity during travel strongly protects against hypertension, but the health system is very little proactive in the primordial and primary prevention of hypertension.

Weight variability, physical functioning and incident disability in older adults.

This study aimed to determine if greater variability in body mass index (BMI) is associated with declines in physical functioning and incident disability in older adults. Included were participants from the Health, Aging and Body Composition Study who had semi-annual BMI data during the first 3years of follow-up. Participants were categorized into quintiles of BMI variability, using two methods. The first method used average successive variability, whereas the second method adjusted these values to remove the variability due to net change in BMI over the 3-year period. Linear regression was used to assess the relationship between the two measures of BMI variability and net changes in BMI, fat mass index, appendicular lean mass index, and Health, Aging and Body Composition Physical Performance Score during the first 3years of the study. Cox proportional hazard models were used to assess the relationship of BMI variability with the subsequent incidence of new disability, adjusting for confounding factors. Among 2121 participants, those in the highest BMI variability quintile were more likely to lose both body mass (β: -0.086 [95% confidence interval, CI: -0.133, -0.040], P<0.01) and fat mass (β: -0.059 [95% CI: -0.117, -0.002], P=0.04) and had greater declines in physical performance score (β: -0.094 [95% CI: -0.162, -0.026], P<0.01) compared to participants with the least variability in BMI. Participants with high BMI variability also had higher rates of incident disability (hazard ratio: 1.36 [95% CI: 1.07, 1.72], P=0.01), independent of net BMI change. BMI variability in older adults is associated with decline in physical performance and incident disability. This relationship cannot be explained by net weight loss alone, supporting it as an independent feature of frailty.

Urinary metabolomic biomarker candidates for skeletal muscle wasting in patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) is an autoimmune disease that affects the joints, leading to chronic synovial inflammation and local tissue destruction. Extra-articular manifestations may also occur, such as changes in body composition. Skeletal muscle wasting is often observed in patients with RA, but methods for assessing loss of muscle mass are expensive and not widely available. Metabolomic analysis has shown great potential for identifying changes in the metabolite profile of patients with autoimmune diseases. In this setting, urine metabolomic profiling in patients with RA may be a useful tool to identify skeletal muscle wasting. Patients aged 40-70years with RA have been recruited according to the 2010 ACR/EULAR classification criteria. Further, the Disease Activity Score in 28 joints using the C-reactive protein level (DAS28-CRP) determined the disease activity. The muscle mass was measured by Dual X-ray absorptiometry (DXA) to generate the appendicular lean mass index (ALMI) by summing the lean mass measurements for both arms and legs and dividing them by height squared (kg/height2 ). Finally, urine metabolomic analysis by 1 H nuclear magnetic resonance (1 H-NMR) spectroscopy was performed and the metabolomics data set analysed using the BAYESIL and MetaboAnalyst software packages. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were applied to the 1 H-NMR data, followed by Spearman's correlation analysis. The combined receiver operating characteristic curve (ROC) was calculated, as well as the logistic regression analyses to establish a diagnostic model. The significance level at P<0.05 was set for all analyses. The total set of subjects investigated included 90 patients with RA. Most patients were women (86.7%), with a mean age of 56.5±7.3years old and a median DAS28-CRP of 3.0 (IQR 1.0-3.0). Fifteen metabolites were identified in the urine samples with high variable importance in projection (VIP scores) by MetaboAnalyst. Of these, dimethylglycine (r=0.205; P=0.053), oxoisovalerate (r=-0.203; P=0.055), and isobutyric acid (r=-0.249; P=0.018) were significantly correlated with ALMI. Based on the low muscle mass (ALMI ≤6.0kg/m2 for women and ≤8.1kg/m2 for men) a diagnostic model have been established with dimethylglycine (area under the curve [AUC]=0.65), oxoisovalerate (AUC=0.49), and isobutyric acid (AUC=0.83) with significant sensitivity and specificity. Isobutyric acid, oxoisovalerate, and dimethylglycine from urine samples were associated with low skeletal muscle mass in patients with RA. These findings suggest that this group of metabolites may be further tested as biomarkers for identification of skeletal muscle wasting.

Growth trajectories during infancy have a significant impact on body composition in childhood

Evidence supports that growth trajectory during infancy has a major impact on body composition. We aimed to examine body composition in children born small for gestational age (SGA) or appropriate for gestational age (AGA) adjusted for postnatal growth velocity. We enrolled 365 children, 75 SGA and 290 AGA, aged 7 to 10 years, examining anthropometrics, skinfold thickness, and body composition using bioelectrical impedance analysis. Growth velocity was defined as rapid or slow (weight gain > or <0.67 z-scores, respectively). Gestational age, sex, delivery mode, gestational diabetes, hypertension, nutrition, exercise, parental body mass index (BMI), and socioeconomic status were considered. At a mean of 9 years of age, SGA compared with AGA-born children, had significantly lower lean mass. BMI was negatively associated with SGA status (beta = 0.80, P = .046), after adjusting for birth weight, delivery mode, and breastfeeding. The lean mass index was negatively associated with SGA status (beta = 0.39, P = .018), after adjusting for the same factors. SGA-born participants with slow growth velocity had significantly lower lean mass in comparison to AGA-born counterparts. SGA-born children with rapid compared with those with slow growth velocity had significantly higher absolute fat mass. BMI was negatively associated with a slow postnatal growth pattern (beta = 0.59, P = .023), and the lean mass index was negatively associated with a slow postnatal growth pattern (beta = 0.78, P = .006), after adjusting for the same factors. In conclusion, SGA-born children presented a lower lean mass in comparison to AGA-born counterparts, whereas BMI and lean mass index were negatively associated with slow postnatal growth velocity.

Body composition and musculoskeletal fitness: A cluster analysis for the identification of risk phenotypes for pediatric sarcopenia

Sarcopenia is primarily a disease in older people characterized by reduced muscle mass and strength. Nevertheless, sarcopenia may, at least partially, have pediatric origins. The study aimed to identify risk phenotypes for sarcopenia in healthy young people using clustering analysis procedures based on body composition and musculoskeletal fitness. We conducted a cluster cross-sectional analysis of data from 529 youth aged 10-18yr. Body composition was assessed using whole-body dual-energy x-ray absorptiometry (DXA), determining: lean body mass index (LBMI, kg/m2), fat body mass index (FBMI, kg/m2), abdominal FBMI (kg/m2), and lean body mass/fat body mass ratio (LBM/FBM); body mass index was also calculated (BMI, kg/m2). Musculoskeletal fitness was assessed using handgrip strength (kg) and vertical jump power (W) tests. Results were presented as absolute values and adjusted by body mass. Plank endurance (s) was also assessed. All variables were sex and age in years standardized (Z-score). LBMI or LBM/FBM ratio≤-1 SD were used to identify participants at risk for sarcopenia. Maturity was estimated as the years of distance from the peak height velocity (PHV) age. Using the Z-score means for body composition and musculoskeletal fitness and having LBMI or LBM/FBM ratio as the categorical variables (at risk vs. not at risk), the cluster analyses indicated three homogeneous groups (phenotypes, P): P1, risk body composition and unfit; P2, non-risk body composition and non-fit, and P3, non-risk body composition and fit. With the LBMI as a categorical variable, the ANOVA models showed that the body composition and absolute values of musculoskeletal fitness were in P1<P2<P3 and the estimated PHV age of P1>P3 in both sexes (p<0.001). Having the LBM/FBM as a categorical variable, higher values of BMI, FBMI, and abdominal FBMI, and lower values of handgrip strength and vertical jump power both adjusted for body mass and plank endurance were observed in P1 than in P2 and/or P3 and the P2 than in the P3 in boys and girls (p<0.001). Two risk phenotypes for sarcopenia were identified in apparently healthy young people: I. a low LBMI phenotype with low BMI and II. a low LBM to FBM phenotype with high BMI and FBMI. In both risk phenotypes I and II, musculoskeletal fitness was low. For screening, we suggest using absolute measures of handgrip strength and vertical jump power in phenotype I and body mass adjusted measures of these markers, as well as the plank endurance time in phenotype II.

Body composition phenotypes and bone health in young adults: A cluster analysis

Lean mass is considered the best predictor of bone mass, as it is an excellent marker of bone mechanical stimulation, and changes in lean mass are highly correlated with bone outcomes in young adults. The aim of this study was to use cluster analysis to examine phenotype categories of body composition assessed by lean and fat mass in young adults and to assess how these body composition categories are associated with bone health outcomes. Cluster cross-sectional analyses of data from 719 young adults (526 women) aged 18-30 years from Cuenca and Toledo, Spain, were conducted. Lean mass index (lean mass (kg)/height (m)2), fat mass index (fat mass (kg)/height (m)2), bone mineral content (BMC) and areal bone mineral density (aBMD) were assessed by dual-energy X-ray absorptiometry. A cluster analysis of lean mass and fat mass index z scores resulted in a classification of a five-category cluster solution that could be interpreted according to the body composition phenotypes of individuals as follows: high adiposity-high lean mass (n=98), average adiposity-high lean mass (n=113), high adiposity-average lean mass (n=213), low adiposity-average lean mass (n=142), and average adiposity-low lean mass (n=153). ANCOVA models showed that individuals in clusters with a higher lean mass had significantly better bone health (z score: 0.764, se: 0.090) than their peers in other cluster categories (z score:-0.529, se: 0.074) after controlling for sex, age, and cardiorespiratory fitness (p<0.05). Additionally, subjects belonging to the categories with a similar average lean mass index but with high or low-adiposity levels (z score: 0.289, se: 0.111; z score: 0.086, se: 0.076) showed better bone outcomes when the fat mass index was higher (p<0.05). This study confirms the validity of a body composition model using a cluster analysis to classify young adults according to their lean mass and fat mass indices. In addition, this model reinforces the main role of lean mass on bone health in this population and that in phenotypes with high-average lean mass, factors associated with fat mass may also have a positive effect on bone status.