Composition Metrics Research Articles

Effects of a Six-Month Physical Activity Program on Health Risk Factors and Body Composition Among Overweight and Obese Middle-Aged Adults

Introduction. Physical activity is vital for preventing and managing lifestyle-related diseases, which pose significant health and socio-economic challenges. This study aimed to evaluate the effects of a six-month supervised physical activity program on health risk factors and body composition in middle-aged individuals with overweight or obesity. Methods. The study involved 166 men and women aged 30 to 65 years, with a body mass index (BMI) ranging from 26 to 35 and moderate to severe health risks. Participants of the study were engaged in a six-month physical activity training program designed in accordance with World Health Organization guidelines. Comprehensive assessments were performed at baseline and after the intervention, including measurements of various anthropometric and body composition parameters, as well as evaluations of functional performance. Fitness tests were also conducted to assess participants’ physical capacity and to monitor improvements throughout the training period. Results. Baseline measures of body mass composition and age demonstrated a strong positive correlation with visceral fat rating (VFR) in both men (r = 0.364, p < 0.001) and women (r = 0.420, p = 0.002). Following the six-month training program, participants exhibited an average improvement of 30% (p < 0.001) in their Cooper endurance test results. The physical activity intervention positively impacted body mass index (BMI) and various body composition metrics, including fat mass, VFR, and muscle mass, across all participants and most subgroups (gender, BMI, and age). In males, training at higher maximum heart rate (HRmax) zones significantly contributed to a reduction in the percentage of fat mass (80–89% HRmax) and an increase in the percentage of muscle mass (70–79% and 80–89% HRmax). Conclusions. The study indicates that a six-month supervised physical activity program significantly improves health risk factors and body composition (visceral fat reduction and improvement in percent of fat and muscle mass) among middle-aged individuals with overweight or obesity. Therefore, we advocate for the integration of structured physical activity interventions into healthcare practices to effectively enhance health outcomes in this population.

Determining the Fitness Level of People with Down Syndrome Living in Kosovo Based on the ALPHA Protocol

Purpose: This study aimed to establish national norm values for body composition and fitness levels among individuals with Down syndrome. It also aimed to investigate gender differences in body composition features and fitness parameters, analyze the impact of the region where individuals with Down syndrome reside, and compare their fitness levels with international peers. Methods: The sample included 81 participants, 40 females (height: 146.6±4.88 cm, weight: 63.6±16.4 kg) and 41 males (height: 157.4±6.21 cm, weight: 66.8±14.8 kg). To assess the physical fitness levels of the participants with Down syndrome, a modified version of the ALPHA testing protocol was used. Findings: The results demonstrated significant gender differences (p<0.05) in body composition and fitness parameters, with males generally exhibiting better outcomes compared to females. Moreover, significant disparities (p<0.05) in body composition and fitness parameters were observed among individuals with Down syndrome residing in different regions of Kosovo. Noteworthy gender disparities exist in terms of body composition and physical fitness metrics, with male participants achieving superior results compared to their female counterparts. Furthermore, noticeable variations were observed among the regional Down syndrome centers, with participants from older centers displaying improved fitness metrics and body composition features compared to those from newly established facilities. Conclusion: Gender differences in body composition and fitness were evident, with males outperforming females, except in muscle mass. Future studies should explore fitness and health barriers in Kosovo's DS population, with a focus on improving physical activity through tailored strategies.

Positive Effects of Aerobic-Resistance Exercise and an Ad Libitum High-Protein, Low-Glycemic Index Diet on Irisin, Omentin, and Dyslipidemia in Men with Abdominal Obesity: A Randomized Controlled Trial.

The aim of this research was to evaluate changes in body composition, adipokine levels, and dyslipidemia parameters in males with abdominal obesity following two distinct interventions: exercise alone and exercise combined with an ad libitum diet. This study included 44 males with abdominal obesity (mean age 34.7 ± 5.5 years, waist circumference [WC] 110.3 ± 8.5, BMI 32.0 ± 3.9), who were randomly assigned to three groups: an experimental group engaging in aerobic-resistance exercise (II, n = 16), an experimental group engaging in aerobic-resistance exercise combined with an ad libitum high-protein, low-glycemic index carbohydrate diet (III, n = 16), both interventions lasting 6 weeks, and a control group without interventions (I, n = 12). Body composition metrics (body mass index [BMI], waist circumference [WC], body fat [BF], abdominal fat [ABD]) and fat-free mass [FFM], along with biochemical blood analyses (irisin [IR], omentin [OMEN], glucose [GLU], insulin [INS], LDL- and HDL-cholesterol), were measured at baseline and after the 6-week intervention. The effects of the interventions on the analyzed variables across groups were assessed using mixed ANOVA tests with post-hoc comparisons. Effect size (ES) was also calculated using partial eta squared (ηp2). The intervention in group III resulted in a significant decrease in IR (p < 0.01, ηp2 = 0.03) by 41% and LDL-C (p < 0.01, ηp2 = 0.02) by 14%. These effects were associated with a reduction in BF (p < 0.01, ηp2 = 0.02) by 14%, ABD (p < 0.01, ηp2 = 0.03) by 31%, and WC (p < 0.01, ηp2 = 0.01) by 3%. In group II, decreases after 6 weeks of intervention were noted only in WC (p = 0.02, ηp2 = 0.01) by 1% and in INS (p < 0.01, ηp2 = 0.04) by 47%. No differences were found between groups. The use of low-glycemic index carbohydrates (p < 0.01, ηp2 = 0.06) and increased protein intake (p < 0.01, ηp2 = 0.30) led to changes in the fiber-to-energy value of the diet ratio (p < 0.01, ηp2 = 0.18) and a reduction in dietary energy value (p < 0.01, ηp2 = 0.13) by 23%, resulting in a greater energy deficit than in the II group. These findings highlight the effect of combining dietary and exercise interventions to achieve significant changes in body composition and metabolic parameters, even over a short period of intervention.

The Effects of Time-Restricted Eating on Fat Loss in Adults with Overweight and Obese Depend upon the Eating Window and Intervention Strategies: A Systematic Review and Meta-Analysis

Time-restricted eating (TRE) is a circadian rhythm-based intermittent fasting intervention that has been used to treat obesity. However, the efficacy and safety of TRE for fat loss have not been comprehensively examined and the influences of TRE characteristics on such effects are unknown. This systematic review and meta-analysis comprehensively characterized the efficacy and safety of TRE for fat loss in adults with overweight and obese, and it explored the influence of TRE characteristics on this effect. Methods: A search strategy based on the PICOS principle was used to find relevant publications in seven databases. The outcomes were body composition, anthropometric indicators, and blood lipid metrics. Twenty publications (20 studies) with 1288 participants, covering the period from 2020 to 2024, were included. Results: Compared to the control group, TRE safely and significantly reduced body fat percentage, fat mass, lean mass, body mass, BMI, and waist circumference (MDpooled = −2.14 cm, 95% CI = −2.88~−1.40, p &lt; 0.001), and increased low-density lipoprotein (LDL) (MDpooled = 2.70, 95% CI = 0.17~5.22, p = 0.037), but it did not alter the total cholesterol, high-density lipoprotein, and triglycerides (MDpooled = −1.09~1.20 mg/dL, 95% CI −4.31~5.47, p &gt; 0.05). Subgroup analyses showed that TRE only or TRE-caloric restriction with an eating window of 6 to 8 h may be appropriate for losing body fat and overall weight. Conclusions: This work provides moderate to high evidence that TRE is a promising dietary strategy for fat loss. Although it may potentially reduce lean mass and increase LDL, these effects do not pose significant safety concerns. This trial was registered with PROSPERO as CRD42023406329.

The Efficacy of Ketogenic Diets (Low Carbohydrate; High Fat) as a Potential Nutritional Intervention for Lipedema: A Systematic Review and Meta-Analysis.

Lipedema is a frequently misdiagnosed condition in women, often mistaken for obesity, which significantly deteriorates both quality of life and physical health. Recognizing the necessity for holistic treatment strategies, research has increasingly supported the integration of specific dietary approaches, particularly ketogenic diets focusing on low-carbohydrate and high-fat intake. to evaluate the impact of ketogenic diets on women with lipedema through a systematic review and meta-analysis. A systematic review and meta-analysis were conducted by reviewing published, peer-reviewed studies addressing the implications of a low-carbohydrate, high-fat (LCHF) ketogenic diet in managing lipedema following comprehensive scrutiny of digital medical databases, such as PubMed, PubMed Central, Science Direct, and the Web of Science. This research was governed by specified parameters, including an established search string composed of search terms and an eligibility criterion (PICO) as denoted by the principal authors. Statistical analysis was carried out using RevMan 5.4.1 software with the Newcastle-Ottawa Scale utilized for quality appraisal of the included studies. Seven studies reporting statistical outcomes were included in the systematic review and meta-analysis following a rigorous quality appraisal and data identification process. Three hundred and twenty-nine female participants were diagnosed with lipedema and treated using a low-carbohydrate, high-fat diet. Data analysis identified the high-fat diet with a mean study duration of 15.85 weeks. Mean Differences (MDs) on changes pre- and post-intervention showed significant reductions in BMI and total body weight [4.23 (95% CI 2.49, 5.97) p < 0.00001 and 7.94 (95% CI 5.45, 10.43) p < 0.00001 for BMI and body weight, respectively]. Other anthropometric measurements, such as changes in waist/hip circumferences and waist/hip ratios, showed a significant reduction in these parameters, with an MD of 8.05 (95% CI 4.66, 11.44) p < 0.00001 and an MD of 6.67 (95% CI 3.35, 9.99) p < 0.0001 for changes in waist and hip circumferences from baseline, respectively. Lastly, changes in pain sensitivity were statistically significant post-intervention [MD 1.12 (95% CI, 0.44, 1.79) p = 0.001]. All studies scored fair on the Newcastle-Ottawa Scale. despite the limited studies and low number of study participants, the review observed a significant reduction in anthropometric and body composition metrics, indicating a potentially beneficial association between LCHF ketogenic diets and lipedema management.

Development of a Macroinvertebrate Multimetric Index for the Evaluation of the Ecological Quality of Lake Nokoué

Nowadays, new tools for assessing the biotic integrity of aquatic environments are used. In Benin, the Macroinvertebrate MultiMetric Lake Index (M3LI) was designed to reveal the current state of Lake Nokoué. The inventory was carried out in eight seasonal data collection campaigns from 2019 to 2021 using an Eckman type grab and a trouble net. The composition, diversity and different metrics were calculated. Thirty-nine metrics grouped into five categories were defined and subjected to selection using a PCA in order to identify the relevant metrics for calculating the index. In the lake, 83 taxa divided into 25 orders and 54 families representing 32,770 specimens were determined. Insects, Molluscs, Crustaceans and Annelids constituted the essential macrofauna which was numerically dominated by Gastropods, Crustaceans, Bivalves and Insects. Of the 5 food functional groups obtained, crushers and collector-gatherers were dominant. Ten metrics relevant and well explained by environmental variables were used to calculate M3LI. The M3LI calculated varied from 6.44 at the station near Dantokpa to 3.38 at the Cotonou channel station with fluctuating water quality between poor quality and good quality. These results clearly explain the responses of the living communities of the lake faced with the various stresses due to daily marine intrusion, the role of receptacle of different continental waters and the various anthropogenic activities plunging the environment into a hypereutrophic state. It is therefore urgent to take measures to restoration of this environment to allow living species to regain their balance of life. This index is also a departure for the establishment of a biomonitoring program for the restoration of the lake.

Dietary intake, energy availability, and power in men collegiate gymnasts.

The purpose was to examine the prevalence of low energy availability (LEA), explore dietary behaviors in men collegiate gymnasts (n = 14), and investigate the relationships between energy availability (EA), body composition, and plyometric performance. Body composition was measured using air displacement plethysmography. Lower- and upper-body peak power (PWRpeak) and modified reactive strength index (RSImod) were calculated from countermovement jump (CMJ) and plyometric push-up (PP) assessments. Energy expenditure was tracked over 3 days, while daily energy and macronutrient intake were recorded. EA was calculated and used to categorize athletes into LEA and non-LEA groups. Pearson correlation coefficients were used to examine relationships between EA, body composition, and performance metrics. 85.7% of athletes (n = 12) exhibited LEA (20.98 ± 5.2 kcals/kg FFM), with non-LEA athletes (n = 2) marginally surpassing the <30 kcal/kg of fat-free mass (FFM) threshold (30.58 ± 0.2 kcals/kg FFM). The cohort (n = 14) consumed insufficient energy (30.5 ± 4.5 kcal/kg/day) and carbohydrates (3.7 ± 1.1 g/kg/day), resulting in LEA (22.36 ± 5.9 kcal/kg/FFM). EA was not correlated with body composition or performance metrics. A high prevalence of LEA may exist in men gymnasts, largely due to a low relative energy and carbohydrate intake.

Patch shape, connectivity and functional groups moderate the responses of bird diversity to agricultural diversification — A meta-analysis

Agricultural expansion and intensification pose significant threats to global biodiversity. However, the conservation of agricultural biodiversity is essential for harmonizing agricultural production with ecological sustainability. Agricultural diversification can mitigate the negative impacts of agriculture on ecosystem functioning and biodiversity. Characteristics of the broader landscape may also play an important moderating role in diversified agricultural landscapes, but are not fully solved. To bridge this gap, we conducted a meta-analysis of peer-reviewed studies to compare bird abundance and species richness in diversified agricultural landscapes compared to those in simplified farmlands and natural landscapes. We also explored the moderating role of species functional groups and 11 metrics of landscape composition, configuration and heterogeneity. We found a generally positive effect of perimeter-to-area ratio of farmland patches, connectivity within farmland patches, and connectivity within patches of natural and semi-natural habitats on bird abundance and species richness. Responses to other landscape metrics were less consistent. For pollinators, the abundance was higher in diversified agricultural landscapes compared to control groups, and particularly when compared to natural landscapes. For natural enemies, the species richness was significantly lower in diversified agricultural landscapes than in natural landscapes, while their abundance was not. The overall abundance and species richness of granivores and frugivores in diversified agricultural landscapes were comparable to those in control landscapes. These results indicated landscape type of control groups, species functional groups, and their interactions had consistent impacts on the responses of bird diversity. We found a vital role of farmland patch shape and connectivity within farmland and habitat patches for bird conservation in diversified agricultural landscapes, which has been rarely reported in previous studies. These insights underscore the need for policymakers and managers to develop farmland management and planning strategies at multiple scales to fulfill growing human demands while achieving biodiversity conservation objectives.

Anisotropic regularization for inversion of fast-ion loss detector measurements

Abstract We introduce an anisotropic regularization framework for the reconstruction of distribution functions from measurements, utilizing an approach that applies distinct regularization techniques such as non-negative constrained Tikhonov, total variation, and Besov-space priors, either penalizing the one-norm or the two-norm, in each dimension to reflect the anisotropic characteristics of the multidimensional data. This method, applied to fast-ion loss detector (FILD) measurements, demonstrates a significant improvement over conventional nonnegative-constrained zeroth-order Tikhonov regularization because the prior information of the form of the distribution allows better reconstructions. The validity of the approach is corroborated through FILD measurements of prompt fast-ion losses in an ASDEX Upgrade discharge, where the reconstructed distribution function agrees well with the prompt-loss distribution predicted by ASCOT simulations. Moreover, we develop a composite quality metric, Q, that combines the mean squared error and the Jaccard index for a comprehensive evaluation of reconstruction accuracy and spatial fidelity. Finally, anisotropic regularization is applied to FILD measurements at ASDEX Upgrade to study fast-ion acceleration by edge-localized modes. The refined analysis resolves fine structure in the pitch of the accelerated ions and clearly shows that some ions are accelerated to over twice the injection energy.

Resting Heart Rate Variability is Independently Associated with Visceral Fat Rating Scores in Saudi Adult Males.

Visceral adipose tissue (VAT) may be a specific modifiable contributor to body composition-related autonomic impairment. To compare heart rate variability (HRV) between groups stratified by visceral fat rating (VFR) and compare associations between HRV and body composition metrics. A cross-sectional study was conducted on healthy men (n=99,age=37.8±13.4 years, body mass index [BMI]=26.9±4.6 kg/m2). HRV was derived from 5-minute electrocardiographic recordings. Body composition (body fat percentage, VFR, and muscle mass to visceral fat ratio [MMVFR]) was estimated using tetrapolar bioelectrical impedance analysis. Participants were categorized into groups according to VFR: G1 (VFR=1-8); G2(VFR=9-12); and G3(VFR>12). Age-adjusted comparisons were made between groups. Independent associations were quantified with multiple linear regressions. P <0.05 was significant. Root-mean square of successive differences (RMSSD) and standard deviation of normal RR intervals (SDNN) were higher for G1 vs. G2 and G3 (p<0.05). Low-frequency power (LF) was higher in G1 than in G2 (p<0.05). VFR and MMVFR were negatively associated with SDNN, RMSSD, LF, and HF (p<0.05). After adjusting for age, BMI, and systolic and diastolic blood pressure, VFR was significantly predictive of RMSSD, SDNN, and HF (p=0.002,-0.027), and MMVFR was significantly predictive of RMSSD and SDNN (p=0.020,-0.023). Men in the lowest VFR category had the highest HRV. VFR was more strongly associated with HRV than body fat percentage and MMVR. Time domain parameters were more sensitive to VAT than frequency domain parameters. HRV parameters could be the primary parameters of interest in tracking cardiac-autonomic status in response to interventions targeting VAT reduction.

Visceral fat area and subcutaneous fat area as measures of body composition in soft tissue sarcoma.

Soft tissue sarcomas (STS) are a heterogenous group of malignancies of mesenchymal origin. Given recent data linking obesity as well as the pattern of fat distribution with cancer outcomes, we sought to investigate the association of visceral fat area (VFA) and subcutaneous fat area (SFA) with oncologic outcomes in patients with STS undergoing surgery. We analyzed data from 88 patients with STS diagnosed from 2008 to 2022. Predictor variables included body mass index (BMI), VFA, and SFA. VFA and SFA were obtained from computed tomography of the abdomen and pelvis. Univariable and multivariable Cox regression analysis was used to analyze associations between predictor variables and overall survival and recurrence-free survival. Although BMI was closely correlated with VFA (r = 0.69, p < 0.0001) and SFA (r = 0.80, p < 0.0001), there was no significant association between high BMI, VFAor SFA, and worse oncologic outcomes. Although VFA and SFA are strongly correlated with BMI, we did not observe BMI nor imaging metrics of fat composition to be associated with worse oncologic outcomes. Further research is needed to elucidate any links between body fat content and metabolic or immune factors governing oncologic outcomes in STS.

Characteristics of the oral microbiome in youth exposed to caregiving adversity

Caregiving adversity (CA) exposure is robustly linked to increased risk for poor oral, physical, and mental health outcomes. Increasingly, the gut microbiome has garnered interest as a contributor to risk for and resilience to such health outcomes in CA-exposed individuals. Though often overlooked, the oral microbiome of CA-exposed individuals may be just as important a contributor to health outcomes as the gut microbiome. Indeed, outside the context of CA, the oral microbiome is well-documented as a regulator of both oral and systemic health, and preliminary data suggest its association with mental health. However, research examining the association between CA and the oral microbiome is extremely sparse, especially in childhood, when the community composition of such organisms is still stabilizing. To address that sparsity, in the current study, we examined composition and differential abundance metrics of the oral microbiome in 152 youth aged 6–16 years, who had either been exposed to significant caregiving adversity (significant separation from or maltreatment by a caregiver; N = 66, CA) or who had always remained with their biological/birth families (N = 86, Comparison). We identified a significant negative association between hair cortisol and oral microbiome richness in the Comparison group that was significantly blunted in the CA group. Additionally, youth in the CA group had altered oral microbiome composition and elevated abundance of potentially pathogenic bacteria relative to youth in the Comparison group. Questionnaire measures of fatigue, somatic complaints, and internalizing symptoms had limited associations with oral microbiome features that were altered in CA. Although we found differences in the oral microbiomes of CA-exposed youth, further research is required to elucidate the implications of those differences for health and well-being.

Changes in Fat Mass Index and Fat-Free Mass Index Vary Significantly by Age and Sex of the Patient, and by Type of Bariatric Surgery.

The loss of fat-free mass after rapid weight loss following bariatric surgery shows BMI is inadequate for reporting weight loss, emphasizing the need for a more accurate body composition metric. This study assessed changes in fat mass index (FMI), fat-free mass index (FFMI), and dietary intake over 6months after one-anastomosis gastric bypass (OAGB), Roux-en-Y gastric bypass (RYGB), and sleeve gastrectomy (SG) across age and sex groups. This prospective observational study included 151 bariatric surgery candidates. Data on demographics, anthropometric, body composition, and food intake data were collected before and 6months after surgery. SPSS version 22 was used for analysis, employing ANOVA and t-tests to assess group differences. Younger patients (≤ 35years) had higher percent total and excess weight loss (%TWL and %EWL) across all bariatric surgeries, and those undergoing SG experienced more favorable changes in fat-free mass (FFM) and visceral fat compared to other procedures (P = 0.002). Males had higher percent change in fat mass index (%∆ FMI) and visceral fat than females with OAGB and RYGB (P < 0.05). Women undergoing SG and RYGB had a more significant decrease in energy intake compared to OAGB (P < 0.001), and the ≤ 35 and 35-44 age groups demonstrated lower reductions in energy intake following OAGB. Age, sex, and surgery type significantly affect bariatric surgery outcomes. Younger patients achieved greater weight-related improvements, while men undergoing RYGB experienced more substantial fat mass changes than women.

Homogenized Modeling of CO2/CO Reduction Catalyst Microenvironments with Intermixed Hydrophobic and Hydrophilic Regions

Electroreduction of CO and CO2 offer a pathway toward renewable-powered synthesis of hydrocarbon chemicals and fuels. Both the composition and the structure of cathodic catalyst microenvironments in gas diffusion electrodes play a dominant role in determining the product composition and efficiency metrics. Porous and hydrophilic copper environments are known to produce multi-carbon species and exhibit large active surface areas, but recent investigations have shown that the inclusion of sporadically-distributed porous hydrophobic regions creates additional pathways for the delivery of gaseous reactants, thereby mitigating transport limitations seen in pure Cu catalysts.As the design space for catalysts has grown to include a wide variety of material and geometric parameters, accurate PDE-based modeling and simulation of such systems has become necessary to understand and optimize the coupled reaction and transport processes that determine cell performance. High fidelity models, however, pose immense computational challenges. Physical and chemical processes occur over a wide variety of spatiotemporal scales, ranging from pore-scale reaction and transport to device-scale gradients in species concentrations. Additionally, the spatial orientation of these features necessitates modeling in multiple dimensions, and transport occurs simultaneously through two phases located within randomly-intermixed porous regions. As a result of all these factors, numerical simulation of high fidelity models is prohibitively expensive.In this work, we develop, numerically simulate, and validate a predictive model that efficiently incorporates a wide range of physical and chemical processes occurring in catalyst microenvironments with intermixed hydrophobic and hydrophilic regions. We employ homogenization as a means of model reduction, constructing a medium fidelity model that captures both microenvironment geometric scales and full device scales in 3D. Our model, coupled with the appropriate numerical methods for treatment of stiff and multi-dimensional problems, permits low-cost exploration of the high-dimensional parameter space associated with recently developed catalysts, offering quantitative insight into the optimal design of microenvironments for CO and CO2 electroreduction.This work is supported by the United States Department of Energy under grant DE-SC0021633.

Establishing feasibility and reliability of subcutaneous fat measurements by ultrasound in very preterm infants.

Regional fat distribution may be a marker of metabolic health and brain growth in preterm infants. Point of care ultrasound has been used to assess regional fat in term infants but has not been used widely in preterm infants. To longitudinally quantify changes in body composition metrics using bedside ultrasound in very preterm infants. Very preterm infants (N = 69) were enrolled after birth and body composition assessments were done through 36 completed weeks' postmenstrual age (PMA). Linear mixed effects regression was used to model change in body composition assessments over time. There was an average increase across PMA for each body composition outcome. Biceps ultrasound subcutaneous fat (SQF) thickness increased by 0.11 mm (95% CI: 0.09, 0.13) each postmenstrual week. Triceps, subscapular, and abdominal ultrasound SQF remained constant through 28 weeks' PMA, then increased each week through 36 completed weeks' PMA. The inter-rater and intra-rater intraclass correlation coefficients for the ultrasound SQF measures ranged from 85.8 to 99.9. Use of ultrasound as a novel method to assess regional fat distribution in very preterm infants is feasible and reliable. Regional fat distribution may be a marker of metabolic health and brain growth in preterm infants. Gold standard body composition assessments may not be feasible in medically fragile very preterm infants. This study assesses longitudinally changes in regional adiposity development using bedside ultrasound techniques in a multicenter cohort of very preterm infants. Results of this study show that bedside ultrasound as a novel method to assess regional subcutaneous fat distribution and development in very preterm infants is both feasible and reliable.

Subcutaneous and Visceral Adipose Tissue Reference Values From the Framingham Heart Study Thoracic and Abdominal CT.

Computed tomography (CT) captures the quantity, density, and distribution of subcutaneous and visceral (SAT and VAT) adipose tissue compartments. These metrics may change with age and sex. The study aims to provide age-, sex-, and vertebral level-specific reference values for SAT on chest CT and for SAT and VAT on abdomen CT. This secondary analysis of an observational study describes SAT and VAT measurements in participants of the Framingham Heart Study without known cancer diagnosis who underwent at least 1 of 2 CT examinations between 2002 and 2011. We used a previously validated machine learning-assisted pipeline and rigorous quality assurance to segment SAT at the fifth, eighth, and tenth thoracic vertebra (T5, T8, T10) and SAT and VAT at the third lumbar vertebra (L3). For each metric, we measured cross-sectional area (cm2) and mean attenuation (Hounsfield units [HU]) and calculated index (area/height2) (cm2/m2) and gauge (attenuation × index) (HU × cm2/m2). We summarized body composition metrics by age and sex and modeled sex-, age-, and vertebral level-specific reference curves. We included 14,898 single-level measurements from up to 4 vertebral levels of 3797 scans of 3730 Framingham Heart Study participants (1889 [51%] male with a mean [standard deviation] age of 55.6 ± 10.6 years; range, 38-81 years). The mean VAT index increased with age from 65 (cm2/m2) in males and 29 (cm2/m2) in females in the <45-year-old age group to 99 (cm2/m2) in males and 60 (cm2/m2) in females in >75-year-old age group. The increase of SAT with age was less pronounced, resulting in the VAT/SAT ratio increasing with age. A free R package and online interactive visual web interface allow access to reference values. This study establishes age-, sex-, and vertebral level-specific reference values for CT-assessed SAT at vertebral levels T5, T8, T10, and L3 and VAT at vertebral level L3.

Unraveling the role of computed tomography derived body composition metrics on anastomotic leakages rates in rectal cancer surgery: A protocol for a systematic review and meta-analysis.

Anastomotic leakage is a major concern following total mesorectal excision for rectal cancer, affecting oncological outcomes, morbidity an treatment costs. Body composition has been suggested to influence anastomotic leakage rates. However, literature on how body composition impact anastomotic leakage rates is conflicting. This systematic review aims to evaluate the role of computed tomography derived body composition metrics on anastomotic leakage rates in rectal cancer patients. Databases PubMed/MEDLINE, Cochrane Library, web of science, and EMBASE, will be systematically searched for papers from January 2010 onwards. Study selection, data collection and quality assessment will be independently performed by three research fellows. Outcomes described in three or more studies will be included in the meta-analysis. The Q-test and I2 statistic will be used to assess statistical heterogeneity between studies. Publication bias will be examined by visual inspection of funnel plots and quantified by Egger's test. Sensitivity analyses will be conducted to examine the robustness of the meta-analysis. Reporting of the findings will be in line with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. This systematic review will synthesize the current evidence and will identify knowledge gaps. Results of the systematic review will aid health care professional in pre-operative decision making and will be distributed through a peer-reviewed publication and presentation of results at international meetings. PROSPERO protocol number: CRD42023471537.

An Update on the iglu Software Package for Interpreting Continuous Glucose Monitoring Data.

Background: Continuous glucose monitors (CGMs) are increasingly used to provide detailed quantification of glycemic control and glucose variability. An open-source R package iglu has been developed to assist with automatic CGM metrics computation and data visualization, providing a comprehensive list of implemented CGM metrics. Motivated by the recent international consensus statement on CGM metrics and recommendations from recent reviews of available CGM software, we present an updated version of iglu with improved accessibility and expanded functionality. Methods: The functionality was expanded to include automated computation of hypo- and hyperglycemia episodes with corresponding visualizations, composite metrics of glycemic control (glycemia risk index and personal glycemic state), and glycemic metrics associated with postprandial excursions. The algorithm for mean amplitude of glycemic excursions has been updated for improved accuracy, and the corresponding visualization has been added. Automated hierarchical clustering capabilities have been added to facilitate statistical analysis. Accessibility was improved by providing support for the automatic processing of common data formats, expanding the graphical user interface, and providing mirrored functionality in Python. Results: The updated version of iglu has been released to the Comprehensive R Archive Network (CRAN) as version 4. The corresponding Python wrapper has been released to the Python Package Index (PyPI) as version 1. The new functionality has been demonstrated using CGM data from 19 subjects with prediabetes and type 2 diabetes. Conclusions: An updated version of iglu provides comprehensive and accessible software for analyses of CGM data that meets the needs of researchers with varying levels of programming experience. It is freely available on CRAN and on GitHub at https://github.com/irinagain/iglu.

Automatic assessment of body composition in children with lymphoma: results of a [18F]FDG-PET/MR study.

To use Dixon-MR images extracted from [18F]FDG-PET/MR scans to perform an automatic, volumetric segmentation and quantification of body composition in pediatric patients with lymphoma. Pediatric patients with lymphoma examined by [18F]FDG-PET/MR at diagnosis and restaging were included. At each time point, axial fat and water Dixon T1w images of the thighs were automatically segmented and muscle volume, subcutaneous, intramuscular, and intermuscular fat volume were quantified. The metabolic activity of the largest nodal lesion and of muscles and subcutaneous fat was recorded. The paired samples t-test and Spearman's correlation coefficient were applied to evaluate potential differences between the two time points and the relationship between metabolic and body composition metrics, respectively. By logistic regression analysis, the prognostic role of the investigated variables was assessed. The applied significance level was p < 0.05 for all analyses. Thirty-seven patients (mean age ± SD 14 ± 3-years-old; 20 females) matched the inclusion criteria. After chemotherapy (interval between the two PET/MR scans, 56-80 days; median 65 days), muscle volume significantly decreased (629 ± 259 cm3 vs 567 ± 243 cm3, p < 0.001) while subcutaneous, intramuscular and intermuscular fat increased (476 ± 255 cm3 vs 607 ± 254 cm3, p < 0.001; 63 ± 20 cm3 vs 76 ± 26 cm3, p < 0.001; 58 ± 19 cm3 vs 71 ± 23 cm3, p < 0.001); the metabolic activity of the main nodal lesion, muscles, and subcutaneous fat significantly decreased (p < 0.05, each). None of the examined variables acted as predictors of the response to treatment (p = 0.283). A strong correlation between BMI and subcutaneous fat volume at diagnosis (r = 0.675, p < 0.001) and restaging (r = 0.600, p < 0.001) emerged. The proposed method demonstrated that pediatric patients with lymphoma undergo muscle loss and an increase of subcutaneous fat during treatment. The proposed automatic and volumetric MR-based assessment of body composition in children with lymphoma can be used to monitor the effect of chemotherapy and may guide tailored exercise programs during chemotherapy. T1w Dixon images can be used for the automatic segmentation and quantification of body composition. Muscle and subcutaneous fat volume do not act as predictors of the response to treatment in children with lymphoma. Chemotherapy induces changes in body composition in children with lymphoma.

The pressure field model: a challenge to the conventional Starling and Guyton model of hemodynamic management

IntroductionEnsuring hemodynamic stability with adequate perfusion to vital organs is critical to the safe conduct of anesthesia. Recent advances in hemodynamic monitoring technologies allow pressure, flow, and resistance to be measured continuously; however, there is limited evidence to suggest that these technologies alter clinical management or improve patient outcomes significantly. This may be because the fundamental hemodynamic model, established by Starling and Guyton, fails to offer the granular level of insight needed to guide clinical management.MethodsWe collected hemodynamic data from 950 patients who underwent major surgery with advanced hemodynamic monitoring (AHM) that provided continuously derived cardiac output and vascular resistance measurements. These measurements were based on the hemodynamic model of Starling and Guyton. Additionally, investigational monitoring software was developed to visualize a different hemodynamic model, termed the “pressure field” model. This model expresses the pulsatile, beat-to-beat relationship between ventricular performance (measured by stroke volume) and vascular tone (indicated by systemic elastance).ResultsWithin this dataset were several patients who experienced major hemorrhage. Case studies of these patients demonstrate that abnormal pressure and flow regulation patterns are observed through the lens of the pressure field model, but these patterns are typically not visible through the lens of the traditional Starling and Guyton model (cardiac output and systemic vascular resistance, which involve averaging hemodynamic performance over successive cardiac cycles). Furthermore, “before and after” case studies using our investigational pressure field monitoring software suggest that the traditional Starling and Guyton hemodynamic model has limited utility in managing hemorrhage.DiscussionWe propose that the pressure field model may allow hemorrhage to be managed more effectively via improved monitoring granularity [the beat-by-beat visualization of the stroke volume-systemic elastance relationship, rather than the use of the composite metrics of cardiac output (heart rate × stroke volume) and systemic vascular resistance]. Further research into the utility of the pressure field model is warranted.