Derivation and validation of simple anthropometric equations to predict adipose tissue mass and total fat mass with MRI as the reference method

Association of organ damage with predicted fat mass in a community-dwelling elderly: the Northern Shanghai study

BACKGROUND

Body fat mass (FM) is associated with multiple organ damage. However, data regarding the relationship between various organ damage and FM are rare in the elderly. Therefore, we aim to perform an analysis on the relationship between organ damage and FM in a geriatric cohort.

METHODS

3331 participants were included in this analysis. Based on age, body height, body weight, waist circumference, and race, we calculated FM with the established formula. Organ damage, including arterial stiffening, lower extremity atherosclerosis, left ventricular hypertrophy (LVH), micro-albuminuria, and chronic kidney disease (CKD), were measured and calculated with standard methods.

RESULTS

All organ damage parameters were significantly related to FM (all p < 0.001). In univariate logistics regression, the highest quartile of FM was tied to the increased risk of arterial stiffening, lower extremity atherosclerosis, LVH, micro-albuminuria, and CKD (all p < 0.05). After adjustment, participants with higher quantiles of FM had a significantly increased odd ratio (OR) for arterial stiffening [OR = 1.51, 95% confidence interval (CI): 1.15-1.99, p = 0.002] and LVH (OR = 1.99, 95% CI: 1.48-2.67, p < 0.001). Moreover, FM was linearly associated with arterial stiffening and LVH in total population and gender subgroups. Independent of confounders, FM was significantly correlated with arterial stiffening, lower extremity atherosclerosis, LVH and CKD in female, while was only related to LVH in male.

CONCLUSIONS

Among various organ damage, elevated FM is significantly and independently associated with arterial stiffening and LVH in the elderly. Compared with men, women with increased FM are more likely to have multiple organ damage.

[Body composition models based on anthropometry, systematic literature review]

Introduction

The body composition determination is carried out through measurement methods that require the use of specialized equipment that is difficult to acquire and manipulate. Therefore, different authors have developed mathematical models for its calculation. The target of this review was to analyze the work carried out on mathematical models of body composition variables from different anthropometric measurements, answering the following questions: what is the corporal variable that the model predicts?, what are the input variables for model development?, how is the patients typification in each model?, what data analysis method has been used?, and how has been the model evaluated? The search was limited to journals found in repositories in the areas of Medicine, Nursing, Biochemistry, Biology, Health, Pharmacology, Immunology, Engineering, and Mathematics. Four hundred and twenty-four articles were found, which were reduced to 30 by applying the systematic literature review process. The analyzed studies are oriented to the prediction of variables related to body fat mass. The evaluation results found for fat-free mass, fat mass and metabolic rate differ according to the comparison technique and the body segments analyzed. The evaluation is mainly based on the intraclass correlation, the Pearson correlation and the coefficient of determination (r2), and they present a good correlation for the population under study.

Brazilian guide to nutrition in bariatric and metabolic surgery

PURPOSE

Brazilian nutrition recommendations for bariatric and metabolic surgery aim to provide knowledge, based on scientific evidence, on nutritional practices related to different surgical techniques in the surgical treatment of obesity and metabolic diseases.

MATERIALS AND METHODS

A systematic literature search was carried out with the appropriate MeSH terms using Medline/Pubmed/LiLACS and the Cochrane database, with the established criteria being based on the inclusion of articles according to the degree of recommendation and strength of evidence of the Classification of Recommendations, Evaluation, Development, and Evaluation System (GRADE).

RESULTS

The recommendations that make up this guide were gathered to assist in the individualized clinical practice of nutritionists in the nutritional management of patients with obesity, including nutritional management in the intragastric balloon; pre and postoperative nutritional treatment and supplementation in bariatric and metabolic surgeries (adolescents, adults, elderly, pregnant women, and vegetarians); hypoglycemia and reactive hyperinsulinemia; and recurrence of obesity, gut microbiota, and inflammatory bowel diseases.

CONCLUSION

We believe that this guide of recommendations will play a decisive role in the clinical practice of nutritionists who work in bariatric and metabolic surgery, with its implementation in health services, thus promoting quality and safety in the treatment of patients with obesity. The concept of precision nutrition is expected to change the way we understand and treat these patients.

Anthropometric estimators of abdominal fat volume in adults with overweight and obesity

BACKGROUND/OBJECTIVES

To evaluate anthropometric measures for the prediction of whole-abdominal adipose tissue volumes V_XAT (subcutaneous V_SAT, visceral V_VAT and total V_TAT) in patients with obesity.

SUBJECTS/METHODS

A total of 181 patients (108 women) with overweight or obesity were analyzed retrospectively. MRI data (1.5 T) were available from independent clinical trials at a single institution (Integrated Research and Treatment Center of Obesity, University of Leipzig). A custom-made software was used for automated tissue segmentation. Anthropometric parameters (AP) were circumferences of the waist (WC) and hip (HC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and the (hypothetical) hip-to-height ratio (HHtR). Agreement was evaluated by standard deviations s_d% of percent differences between estimated volumes (using results of linear AP-V_XAT regression) and measured ones as well as Pearson's correlation coefficient r.

RESULTS

For SAT volume estimation, the smallest s_d% for all patients was seen for HC (25.1%) closely followed by HHtR (25.2%). Sex-specific results for females (17.5% for BMI and 17.2% for HC) and males (20.7% for WC) agreed better. VAT volumes could not be estimated reliably by any of the anthropometric measures considered here. TAT volumes in a mixed population could be best estimated by BMI closely followed by WC (roughly 17.5%). A sex-specific consideration reduced the deviations to around 16% for females (BMI and WC) and below 14% for males (WC).

CONCLUSIONS

We suggest the use of sex-specific parameters-BMI or HC for females and WC for males-for the estimation of abdominal SAT and TAT volumes in patients with overweight or obesity.

Anatomic description of the distal great saphenous vein to facilitate peripheral venous access during resuscitation: a cadaveric study

The distal great saphenous vein is a popular site for venous access by means of percutaneous cannulation or venous cutdown in a hemodynamically unstable patient. The aim of this study was to precisely define the surface anatomy and dimensions of the distal part of the great saphenous vein to facilitate the aforementioned procedures. Cross-sectional anatomy of the distal saphenous vein was studied in 24 cadaveric ankles sectioned at a horizontal plane across the most prominent points of the medial and lateral malleoli. The curvilinear distance from the most prominent point of the medial malleolus to the center of the saphenous vein, its widest collapsed diameter and skin depth were obtained. The great saphenous vein was located at a mean distance of 24.4 ± 7.9 mm anterior to the medial malleolus. The mean widest collapsed diameter was 3.8 ± 1.5 mm. The mean distance from the skin surface to the vein was 4.1 ± 1.2 mm. These measurements could be used to locate the saphenous vein accurately, particularly in hemodynamically unstable patients with visually indiscernible veins.

Criterion-Related Validity of Field-Based Methods and Equations for Body Composition Estimation in Adults: A Systematic Review

PURPOSE OF REVIEW

Overweight and obesity are associated to health prognosis. Therefore, body composition assessment is an important health outcome, especially in adult population. We analyzed the criterion-related validity of existing field-based methods and equations for body composition estimation in adults aged 19-64 years.

RECENT FINDINGS

One hundred studies met inclusion criteria. The field-based methods, waist circumference (WC), body adiposity index (BAI), and body mass index (BMI) are valid to indicate body adiposity. Likewise, several equations, including the classical Durnin/Womersley equation, Jackson/Pollock equation (males), and Jackson, Pollock, and Ward equation (females), are valid to estimate total body fat mass or body fat percentage. Anthropometric field methods can provide a simple, quick, and easy informative indicators of adiposity in adults. Classical equations, such as Durnin/Womersley equation, Jackson/Pollock equation, and Jackson, Pollock, and Ward equation, are still valid to estimate total body fat mass or body fat percentage in adult population. When choosing estimation equations, specific population characteristics, such as age, weight status, or race ethnicity, should be taken into account. (Trial Registration: Registered on PROSPERO (CRD42020194272)).

Tackling Dyslipidemia in Obesity from a Nanotechnology Perspective

Obesity and dyslipidemia are the main features of metabolic syndrome, expressed mainly by adipose tissue dysfunction and connected by similar pathways and pharmacotherapy. Conventional drugs used in these two associated disorders are limited due to poor drug efficiency, non-specificity, and toxic side effects. Therefore, novel solutions for tackling obesity-associated diseases and providing insights into the development of innovative or improved therapies are necessary. Targeted nanotherapy is a revolutionary technology, offering a promising solution for combatting the disadvantages of currently available therapies for treating obesity and dyslipidemia due to its superior features, which include specific cell targeting, the protection of drugs against physiological degradation, and sustained drug release. This review presents a brief assessment of obesity and dyslipidemia, their impacts on human health, current treatment, and limitations, and the role and potential use of nanotechnology coupled with targeted drug delivery and nutraceuticals as emerging therapies. To the best of our knowledge, this paper presents, for the first time in the literature, a comparison between obesity and dyslipidemia nano-formulations based on drugs and/or natural extracts applied in experimental studies.

Derivation and validation of a simple anthropometric equation to predict fat-free mass in patients with chronic hepatitis C

BACKGROUND

Loss of skeletal muscle mass is very common in chronic liver diseases and affects 30.0-70.0% of the patients with cirrhosis. Given the relevance of muscle wasting in hepatic diseases, a practical screening tool for earlier detection of skeletal muscle mass loss is of utmost significance.

AIMS

To develop and validate a simple anthropometric prediction equation for fat-free mass estimation by using Bioelectrical Impedance Analysis (BIA) as a reference method in patients with chronic hepatitis C (CHC).

METHODS

We prospectively, included 209 CHC patients, randomly allocated into two groups, 158 patients in a development model (derivation sample) and 51 patients in a validation group (validation sample). Predictive equations were developed using backward stepwise multiple regression and the most adequate and simplest derived predictive equation was further explored for agreement and bias in the validation sample. The accuracy of the predictive equation was evaluated using the coefficient of determination (R²).

RESULTS

The predictive equation with an optimal R² was Fat-Free Mass (Kg) = Sex × 0.17 + Height (m) × 16.83 + Weight (Kg) × 0.62 + Waist Circumference (cm) × (-0.15) + Weight (Kg) × Sex × (-0.30) + Sex × Waist Circumference (cm) × 0.14-6.23; where sex = 1 for female and 0 for male. R² = 0.93, standard error of the estimate = 2.6 Kg and coefficient of variation = 20.0%, p < 0.001.

CONCLUSIONS

Our developed and cross-validated anthropometric prediction equation for fat-free mass estimation by using BIA attained a high coefficient of determination, a low standard error of the estimate, and lowermost coefficient of variation. This study indicates that predictive equations may be reliable and useful alternative methods for clinical evaluation of fat-free mass in patients with CHC.

Direct Comparison of (Anthropometric) Methods for the Assessment of Body Composition

OBJECTIVE

Several methods for the assessment of body composition exist, yet they yield different results. The present study aimed to assess the extent of these differences on a sample of young, healthy subjects. We hypothesised that differences in body composition results obtained with different methods will vary to the extent that a subject can be misclassified into different nutritional categories.

RESEARCH METHODS AND PROCEDURES

Underwater weighing (UWW), bioelectrical impedance analysis (BIA), anthropometry (ANT), and dual-energy X-ray absorptiometry (DXA) were used to assess body composition. An extensive list of ANT regression equations (or sets of equations) was analysed in terms of accuracy and precision relative to DXA.

RESULTS

When DXA-determined body fat (BF) values were taken as a reference, UWW overestimated BF in both genders. In contrast, BIA (measured with a given bioimpedance analyser) underestimated BF in females, although BIA-determined BF did not differ from DXA in males. A huge difference in BF estimates (8-29% for females and 6-29% for males, for DXA-determined BF of 25.5% and 13.9% for females in males, respectively) was observed across a number of ANT regression equations; yet, ANT proved not to be inferior to DXA, provided that regression equations with the highest combinations of accuracy and precision were chosen.

CONCLUSIONS

The study proved grounds for comparison of body composition results of young, healthy subjects, obtained with different methods and across a wide range of ANT regression equations. It also revealed a list of the most appropriate ANT regression equations for the selected sample and reported their accuracy and precision.

Novel anthropometric parameters to define obesity and obesity-related disease in adults: a systematic review

Context

Obesity is defined as an abnormal or excessive accumulation of body fat. Traditionally, it has been assessed using a wide range of anthropometric, biochemical, and radiological measurements, with each having its advantages and disadvantages.

Objective

A systematic review of the literature was conducted to identify novel anthropometric measurements of obesity in adults.

Data Sources

Using a combination of MeSH terms, the PubMed database was searched.

Data Extraction

The current systematic review was conducted in accordance with the PRISMA guidelines. The data extracted from each study were (1) details of the study, (2) anthropometric parameter(s) evaluated, (3) study methods, (4) objectives of the study and/or comparisons, and (5) main findings/conclusions of the study.

Data Analysis

The search yielded 2472 articles, of which 66 studies were deemed eligible to be included. The literature search identified 25 novel anthropometric parameters. Data on novel anthropometric parameters were derived from 26 countries. Majority were descriptive cross-sectional studies (n = 43), while 22 were cohort studies. Age range of the study populations was 17–103 years, while sample size varied from 45 to 384 612.

Conclusions

The novel anthropometric parameters identified in the present study showed variable correlation with obesity and/or related metabolic risk factors. Some parameters involved complex calculations, while others were derived from traditional anthropometric measurements. Further research is required in order to determine the accuracy and precision.

Body mass index and mobility limitations: An analysis of middle-aged and older Black, Hispanic, and White women in the U.S

INTRODUCTION

While the Body Mass Index (BMI) did not change significantly for men from 2005 to 2014 in the United States, women exhibited an upward linear trend. Hispanic and Black women, in particular, showed a dramatic increase. Therefore, the objective of this study was to examine the association between BMI and mobility limitations for non-institutionalised middle-aged and older Black, Hispanic, and White women.

METHODS

The International Classification of Functioning, Disability, and Health model was applied to a sample of 2865 Black, 1846 Hispanic, and 9721 White women categorised as middle-aged and older (i.e., at least 50 years of age) from the 2010 and 2014 Rand Health and Retirement Study. A random effects ordered logit was employed.

RESULTS

After accounting for personal/activity characteristics, the analyses revealed Black women with greater BMI were associated with a higher likelihood for mobility limitations with an odds ratio of 1.11 [1.06-1.16, 95% CI]. A significant association was also found for Hispanic women with an odds ratio of 1.16 [1.11-1.23, 95% CI] and White women with an odds ratio of 1.16 [1.13-1.19, 95% CI]. Even after accounting for the possibility of endogeneity, BMI remained robust.

CONCLUSION

Higher-levels of BMI were associated with an increased probability for mobility limitations for Black, Hispanic, and White middle-aged and older women. Those with a vigorous exercise regimen were less likely to be in this category across all ranges of BMI. These results are useful for prioritising minority health policy, particularly given the limited amount of existing research in this specific area.

Attenuation of the association between sugar-sweetened beverages and diabetes risk by adiposity adjustment: a secondary analysis of national health survey data

Purpose

While weight gain and obesity are the dominant factors, dietary sugar and specifically sugar-sweetened beverages (SSB) has been implicated in causing type 2 diabetes (T2DM). We assessed how much of the apparent effect of SSB is explained by adiposity, but not captured by adjustment for BMI, which is a poor index of body fat.

Methods

We examined data from 5187 adults (mean age 50.8 years, SD = 16.4, 172 (3.3%) T2DM), from the Scottish Health Survey 2003 and 2008–2010 databases. Logistic regression was used to assess the association between SSB consumption and T2DM (non-insulin treated) and its attenuation (reduction in odds ratios, ORs), after entering published anthropometric indices of adiposity into the regression model, adjusted for age, sex, social class, education, smoking, alcohol consumption and physical activity.

Results

Compared with low SSB categories (“less often/never”, once/week or 1–3 times/month), the OR without adiposity adjustment for having T2DM in high SSB consumers (2–3, 4–5, ≥ 6/day) was 2.56 (95% CI 1.12–5.83; p = 0.026). That OR was marginally changed by adjusting for BMI (+ 4.3%), WC (+ 5.5%) or total body fat (− 4.3%), but greatly attenuated by adjusting for estimated %body fat (− 23.4%). These indices had similar influences on the associations between SSB and T2DM combining known T2DM patients with unknown HbA_1c > 6.5%, > 48 mmol/mol.

Conclusions

Associations between SSB and T2DM are attenuated more markedly by adjustment with estimated %body fat than with BMI, indicating an adiposity effect not captured using BMI. Future research should employ best available estimates of adiposity.

Estimating Gestational Age From Ultrasound Fetal Biometrics

OBJECTIVE

To compare the accuracy of a new formula with one developed in 1984 (and still in common use) and to develop and compare racial and ethnic-specific and racial and ethnic-neutral formulas.

METHODS

The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies-Singletons was a prospective cohort study that recruited women in four self-reported racial-ethnic groups-non-Hispanic black, Hispanic, non-Hispanic white, and Asian-with singleton gestations from 12 U.S. centers (2009-2013). Women with a certain last menstrual period confirmed by first-trimester ultrasonogram had longitudinal fetal measurements by credentialed study ultrasonographers blinded to the gestational age at their five follow-up visits. Regression analyses were performed with linear mixed models to develop gestational age estimating formulas. Repeated cross-validation was used for validation. The estimation error was defined as the mean squared difference between the estimated and observed gestational age and was used to compare the formulas' accuracy.

RESULTS

The new formula estimated the gestational age (±2 SD) within ±7 days from 14 to 20 weeks of gestation, ±10 days from 21 to 27 weeks of gestation, and ±17 days from 28 to 40 weeks of gestation. The new formula performed significantly better than a formula developed in 1984 with an estimation error of 10.4 compared with 11.2 days from 21 to 27 weeks of gestation and 17.0 compared with 19.8 days at 28-40 weeks of gestation, respectively. Racial and ethnic-specific formulas did not outperform the racial and ethnic-neutral formula.

CONCLUSION

The NICHD gestational age estimation formula is associated with smaller errors than a well-established historical formula. Racial and ethnic-specific formulas are not superior to a racial-ethnic-neutral one.

Obesity: a chronic relapsing progressive disease process. A position statement of the World Obesity Federation

This paper considers the argument for obesity as a chronic relapsing disease process. Obesity is viewed from an epidemiological model, with an agent affecting the host and producing disease. Food is the primary agent, particularly foods that are high in energy density such as fat, or in sugar-sweetened beverages. An abundance of food, low physical activity and several other environmental factors interact with the genetic susceptibility of the host to produce positive energy balance. The majority of this excess energy is stored as fat in enlarged, and often more numerous fat cells, but some lipid may infiltrate other organs such as the liver (ectopic fat). The enlarged fat cells and ectopic fat produce and secrete a variety of metabolic, hormonal and inflammatory products that produce damage in organs such as the arteries, heart, liver, muscle and pancreas. The magnitude of the obesity and its adverse effects in individuals may relate to the virulence or toxicity of the environment and its interaction with the host. Thus, obesity fits the epidemiological model of a disease process except that the toxic or pathological agent is food rather than a microbe. Reversing obesity will prevent most of its detrimental effects.

Sugar and Type 2 diabetes

BACKGROUND

Consumption of sugar, specifically sugar-sweetened beverages, has been widely held responsible by the media for the global rise in Type 2 diabetes (T2DM).

SOURCES OF DATA

Systematic reviews and dietary guidelines relating dietary sugars to T2DM.

AREAS OF AGREEMENT

Weight gain and T2DM incidence are associated with diet and lifestyle patterns characterized by high consumptions of any sweetened beverages. High sugar intakes impair risk factors for macrovascular complications of T2DM.

AREAS OF CONTROVERSY

Much of the association between sugars and T2DM is eliminated by adjusting data for body mass index (BMI). However, BMI adjustment does not fully account for adiposity (r²=0.65-0.75). Excess sugar can promote weight gain, thus T2DM, through extra calories, but has no unique diabetogenic effect at physiological levels.

GROWING POINTS

Ethical concerns about caffeine added to sweetened beverages, undetectable by consumers, to increase consumption.

AREAS TIMELY FOR DEVELOPING RESEARCH

Evidence needed for limiting dietary sugar below 10% energy intake.

A clinical perspective of obesity, metabolic syndrome and cardiovascular disease

The metabolic syndrome is a condition characterized by a special constellation of reversible major risk factors for cardiovascular disease and type 2 diabetes. The main, diagnostic, components are reduced HDL-cholesterol, raised triglycerides, blood pressure and fasting plasma glucose, all of which are related to weight gain, specifically intra-abdominal/ectopic fat accumulation and a large waist circumference. Using internationally adopted arbitrary cut-off values for waist circumference, having metabolic syndrome doubles the risk of cardiovascular disease, but offers an effective treatment approach through weight management. Metabolic syndrome now affects 30-40% of people by age 65, driven mainly by adult weight gain, and by a genetic or epigenetic predisposition to intra-abdominal/ectopic fat accumulation related to poor intra-uterine growth. Metabolic syndrome is also promoted by a lack of subcutaneous adipose tissue, low skeletal muscle mass and anti-retroviral drugs. Reducing weight by 5-10%, by diet and exercise, with or without, anti-obesity drugs, substantially lowers all metabolic syndrome components, and risk of type 2 diabetes and cardiovascular disease. Other cardiovascular disease risk factors such as smoking should be corrected as a priority. Anti-diabetic agents which improve insulin resistance and reduce blood pressure, lipids and weight should be preferred for diabetic patients with metabolic syndrome. Bariatric surgery offers an alternative treatment for those with BMI ≥ 40 or 35-40 kg/m(2) with other significant co-morbidity. The prevalence of the metabolic syndrome and cardiovascular disease is expected to rise along with the global obesity epidemic: greater emphasis should be given to effective early weight-management to reduce risk in pre-symptomatic individuals with large waists.