Métodos de análise da composição corporal em adultos obesos

Validity and reliability of portable A-mode ultrasound in measuring body fat percentage: A systematic review with meta-analysis

The present Systematic Review with Meta-analysis study aimed to evaluate the validity and reliability of the Portable A-mode Ultrasound (P-US) for measuring body fat percentage (BF%). Only studies with participants of both genders which had assessed BF% using P-US compared to the reference standard were selected. Publications up until May 31, 2022 were searched in the MEDLINE, COCHRANE, Science Direct, Web of Science, LILACS, SciELO, PEDro, SPORT Discus, CINAHL and SCOPUS databases. QUADAS-2 was used to assess the risk of bias in the validity studies and QAREL was used for the methodological quality of reliability studies. The JAMOVI software program synthesized the results, from which the Pearson Correlation Coefficient (r) or the square root of the Multiple Linear Regression Determination Coefficient (R2) were extracted for the validity studies, and the Mean of Errors of the Bland-Altman Test (ME) and the Confidence Interval (95%CI) with Upper and Lower Limits for the reliability studies. A total of 13 studies were included, generating 26 results for the quantitative synthesis, 14 for validity and 12 for reliability. Regarding the validity results, a strong correlation was identified between the equipment (r = 0.870 [0.845-0.895], P<0.001), with moderate and true heterogeneity (I2 = 53.47%, P = 0.003), presenting publication bias. A small effect size was identified regarding the reliability results, overestimating the results due to chance between the devices (ME = 0.207 [-0.798-1.212], P = 0.686), with low heterogeneity also due to chance (I2 = 19.44%, P = 0.253), with no publication bias. All of the evaluated studies showed some violation of the instruments, confirming the high risk of bias and the low methodological quality. There is concern with heterogeneity for the validity results explained by the subgroups' analysis. The P-US associated with anthropometric perimeters satisfactorily measures the BF% with samples greater than 100 participants, and males. The results in the reliability assessment show high agreement and high variability, greatly expanding the confidence interval, which should be viewed with reservations. This review received financial support from the Brazilian Air Force. The study was registered with PROSPERO under the number CRD42020166617.

BODY COMPOSITION ASSESSED BY DUAL-ENERGY X-RAY ABSORPTIOMETRY ON METABOLIC PROFILE AND CARDIOVASCULAR RISK IN OBESE PATIENTS PRIOR TO BARIATRIC SURGERY

BACKGROUND

Fat, muscle, and bone are endocrine organs capable of affecting the metabolic profile and cardiovascular risk. Relating these components is important to the establishment of early intervention strategies for overweight patients.

AIMS

This study aimed to evaluate the influence of body mass components on the metabolic profile and cardiovascular risk in the preoperative period of bariatric surgery.

METHODS

A cross-sectional study was conducted with patients admitted for bariatric surgery at a university hospital in the city of Recife, Brazil, between 2018 and 2019. Body composition was determined using dual-energy x-ray absorptiometry. Cardiovascular risk was assessed using the Framingham risk score. Data were collected on anthropometric, clinical, and lifestyle characteristics. The lipid profile (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides), blood glucose, and vitamin D were determined using the standard methods of the hospital laboratory.

RESULTS

A total of 60 patients were analyzed, 86.7% of whom had comorbidities, 33.3% had moderate/high cardiovascular risk, and 71.4% had vitamin D insufficiency/deficiency. Lower lean body mass (adjusted PR 3.24; 95%CI 1.19-5.77) was independently associated with the severity of obesity. The body mass index and waist circumference were negatively correlated with lean body mass (r=-0.52; p<0.01)/r=-0.36; p<0.01). Lean body mass was negatively correlated with fat mass (r=-0.26; p<0.05), trunk fat (r=-0.29; p<0.05), fasting glucose (r=-0.26; p<0.05), and bone mineral density (r=-0.26; p<0.05). A total of 84.2% of individuals with less trunk fat tended to have low cardiovascular risk (p=0.05). However, physical inactivity (adjusted PR 2.14; 95%CI 1.19-5.54) and the risk of alcohol dependence (adjusted PR 2.41; 95%CI 1.76-4.15) were the only variables independently associated with cardiovascular risk.

CONCLUSION

Obese patients in the preoperative period of bariatric surgery with less trunk fat tended to have low cardiovascular risk. However, the other components of body mass were also not associated with cardiovascular risk.

Determining factors of functioning in hemodialysis patients using the international classification of functioning, disability and health

Background

Hemodialysis (HD) treatment affects functioning, physical activity level, clinical biomarkers, and body composition. However, the association between these variables with functioning, considering International Classification of Functioning, Disability and Health (ICF) domains remains unclear. Thus, the aim of this study was to investigate the possible association between physical activity, biomarkers, and body composition with functioning in HD patients in reference to the ICF.

Methods

Eighty HD patients performed different tests grouped according to ICF domain: Body structure and function – handgrip strength (HS), 5-repetition sit-to-stand test, and 60-s sit-to-stand test (5-STS, 60-STS, respectively); Activity – short physical performance battery (SPPB); and Participation – participation scale questionnaire. Physical activity [Human Activity Profile questionnaire (HAP)], body composition (Dual-energy X-ray absorptiometry), Parathormone (PTH), and alkaline phosphatase were analyzed as possible variables associated with ICF domains. Data analyses were performed using simple and multiple regression models adjusted for age, duration of HD, and diuresis volume.

Results

In the body structure and function domain, appendicular lean mass, PTH level, and age were associated with HS (R² = 0.558); HAP and PTH were associated with 5-STS (R² = 0.263); and HAP, PTH, duration of HD, and age were associated with 60-STS (R² = 0.337). In the activity domain, HAP, PTH, alkaline phosphatase, duration of HD, age, and body fat were associated with SPPB (R² = 0.689). Finally, only HAP was associated with the participation scale (R² = 0.067).

Conclusion

Physical activity and PTH levels are determinant protagonists of functioning in all ICF domains in hemodialysis patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02719-5.

Official position of the Brazilian Association of Bone Assessment and Metabolism (ABRASSO) on the evaluation of body composition by densitometry: part I (technical aspects)—general concepts, indications, acquisition, and analysis

Objective

To review the technical aspects of body composition assessment by dual-energy X-ray absorptiometry (DXA) and other methods based on the most recent scientific evidence.

Materials and methods

This Official Position is a result of efforts by the Scientific Committee of the Brazilian Association of Bone Assessment and Metabolism (Associação Brasileira de Avaliação Óssea e Osteometabolismo, ABRASSO) and health care professionals with expertise in body composition assessment who were invited to contribute to the preparation of this document. The authors searched current databases for relevant publications. In this first part of the Official Position, the authors discuss the different methods and parameters used for body composition assessment, general principles of DXA, and aspects of the acquisition and analysis of DXA scans.

Conclusion

Considering aspects of accuracy, precision, cost, duration, and ability to evaluate all three compartments, DXA is considered the gold-standard method for body composition assessment, particularly for the evaluation of fat mass. In order to ensure reliable, adequate, and reproducible DXA reports, great attention is required regarding quality control procedures, preparation, removal of external artifacts, imaging acquisition, and data analysis and interpretation.

Estimations of body fat by anthropometry or bioelectrical impedance differ from those by dual-energy X-ray absorptiometry in prefrail community-dwelling older women

This study aimed to compare different methods to assess body fat (BF). We hypothesized that bioelectrical impedance analysis (BIA) or anthropometry may be used to estimate BF in prefrail older women, equivalently to dual-energy X-ray absorptiometry (DXA). The cross-sectional study included 72 prefrail community-dwelling older women (71.13 ± 4.65 years old; body mass index [BMI] 28.89 ± 4.23 kg/m²). The BF percentage (%BF) was estimated using anthropometry with the Durnin & Womersley (D&W) and Petroski's predictive equations, BIA with 2 Baumgartner predictive equations (BIA 1 and BIA 2), and DXA. All methods differed significantly from DXA according to assessments using repeated measures ANOVA and pairwise comparisons. The mean %BF varied between 39.99 ± 3.42% (D&W) and 43.93 ± 5.06% (DXA). Multiple regression analysis with age and BMI as covariates showed positive correlations (R² = 0.91) in models with D&W equation and BMI, and with BIA 2 and BMI; however, BMI explained more of the model (71%) than the equations. Furthermore, Bland-Altman test revealed a proportional bias for D&W and for BIA 2, with underestimation of BF varying across different %BF values. Petroski's skinfold equation showed a positive correlation on linear regression (R² = 0.74) and no proportional bias; however, Bland-Altman analysis revealed high limits of agreement (-13.6 to -0.05), thus compromising clinical application. To conclude, compared with DXA, all the equations tested showed a high disagreement and wide limits of agreement, restricting their use in clinical practice to estimate the BF in prefrail older women.

Prevalence of Sarcopenic Obesity and its Association with Functionality, Lifestyle, Biomarkers and Morbidities in Older Adults: the FIBRA-RJ Study of Frailty in Older Brazilian Adults

OBJECTIVES

To assess the prevalence of sarcopenic obesity and its association with functionality, lifestyle, biomarkers, and morbidities in older adults.

METHODS

The study analyzed cross-sectional data from 270 older adults who participated in phase III of the Frailty in Brazilian Older People Study (Fragilidade em Idosos Brasileiros-Rio de Janeiro, FIBRA-RJ study-2013). They took part in a home interview surveying socioeconomic, demographic, lifestyle, morbidities, and functional data. Blood was collected for biochemical marker analysis and participants' body composition was determined by dual-energy X-ray absorptiometry. For women, the diagnosis of sarcopenic obesity was defined at a body fat percentage ≥38% and appendicular skeletal muscle mass index (ASMMI) <5.45 kg/m2. For men, a fat percentage ≥27% and ASMMI <7.26 kg/m2 was defined as sarcopenic obesity. Multivariate analysis was performed using a multinomial regression model (95% confidence intervals), with sarcopenic obesity as the outcome.

RESULTS

The prevalence of sarcopenic obesity was 29.3%. In the final fitted model, the variables that displayed statistically significant association with sarcopenic obesity were lower gait speed, self-reported medical diagnosis of arthrosis or arthritis, and high levels of glycemia.

CONCLUSION

The study showed a high prevalence of sarcopenic obesity in non-institutionalized older adults in Brazil. The finding that this condition was associated with modifiable risk factors may provide insights into measures directed at prevention and reduction of the risk of sarcopenic obesity in this population subgroup.

Agreement Between Body Composition Assessed by Bioelectrical Impedance Analysis and Doubly Labeled Water in Obese Women Submitted to Bariatric Surgery : Body Composition, BIA, and DLW

INTRODUCTION

Bariatric surgery has a significant influence on body composition (BC), which should be monitored. However, there is a need to recommend low-cost practical methods, with good estimation of BC for class III obese and/or bariatric patients.

OBJECTIVE

The aim of this study was to determine accuracy and agreement between BC assessed by direct segmental multifrequency bioelectrical impedance analysis (DSM-BIA) and doubly labeled water (DLW) as reference method.

MATERIAL AND METHODS

Twenty class III obese women (age 29.3 ± 5.1 years; body mass index 44.8 ± 2.4 kg/m²) underwent Roux-en-Y gastric bypass surgery. BC (fat mass [FM], fat-free mass [FFM], and total body water [TBW]) was assessed by InBody 230 and DLW in the following periods: before and 6 and 12 months after surgery. Accuracy between the methods was evaluated by the bias and root mean square error. Pearson's correlation, concordance correlation coefficient (CCC), and Bland-Altman method were used to evaluate agreement between the methods.

RESULTS

Correlations were significant (p < 0.001) and CCC was good/excellent between both methods for the evaluation of FM (r = 0.84-0.92, CCC = 0.84-0.95), FFM (r = 0.73-0.90, CCC = 0.68-0.80), and TBW (r = 0.76-0.91, CCC = 0.72-0.81) before and after bariatric surgery. In addition, no significant bias was observed between DSM-BIA and DLW for FM (mean error [ME] = - 1.40 to 0.06 kg), FFM (ME = 0.91-1.86 kg), and TBW (ME = 0.71-1.24 kg) measurements.

CONCLUSION

The DSM-BIA was able to estimate the BC of class III obese women submitted to bariatric surgery with values consistent with those of the DLW method.

Adductor pollicis muscle thickness has a low association with muscle mass and lean mass in kidney transplantation patients

BACKGROUND AND AIMS

The use of adductor pollicis muscle thickness (APMT) as a predictor of muscle and lean mass is not fully understood and little is known whether the APMT evaluation presents advantages when compared to simpler anthropometric measurements, such as body weight. We aimed to associate APMT, alone and plus body weight, with muscle mass and lean mass in kidney transplantation patients.

METHODS

A cross-sectional study was carried out with 129 kidney transplantation patients of both sexes that presented a high time of kidney transplant (95.6 ± 78.3 months). Body weight and height were performed and APMT was measured using a caliper. Lean mass and muscle mass were estimated by bioelectrical impedance.

RESULTS

After linear regression analysis, APMT explained the variances of muscle mass and lean mass by 20% (R² = 0.208; β = 0.456; p < 0.001) and by 26% (R² = 0.264; β = 0.514; p < 0.001), respectively. Body weight predicted muscle mass by 21% (R² = 0.216; β = 0.465; p < 0.001) and lean mass by 68% (R² = 0.684; β = 0.828; p < 0.001). Analyzing weight plus APMT, the prediction of muscle mass and lean mass increased by 8% (R² = 0.29; β = 0.325; p < 0.001) and by 3% (R² = 0.71; β = 0.749; p < 0.001), respectively; when compared to weight alone.

CONCLUSION

Compared with body weight, APMT presented a similar association with muscle mass, but showed a lower prediction of lean mass. In this way, the evaluation of body weight, instead of APMT, seems to have a better cost-benefit to predict both muscle mass and lean mass in kidney transplantation patients.