ABSTRACT
OBJECTIVE: To present an updated and evidence-based guideline for the use of dual-energy x-ray absorptiometry (DXA) to assess body composition in clinical practice. MATERIALS AND METHODS: This Official Position was developed by the Scientific Committee of the Brazilian Association of Bone Assessment and Metabolism (Associação Brasileira de Avaliação Óssea e Osteometabolismo, ABRASSO) and experts in the field who were invited to contribute to the preparation of this document. The authors searched current databases for relevant publications in the area of body composition assessment. In this second part of the Official Position, the authors discuss the interpretation and reporting of body composition parameters assessed by DXA and the use of DXA for body composition evaluation in special situations, including evaluation of children, persons with HIV, and animals. CONCLUSION: This document offers recommendations for the use of DXA in body composition evaluation, including indications, interpretation, and applications, to serve as a guiding tool in clinical practice and research for health care professionals in Brazil.
Subject(s)
Bone Density , Osteoporosis , Absorptiometry, Photon , Body Composition , Brazil , Humans , Osteoporosis/diagnostic imaging , Societies, MedicalABSTRACT
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.
Subject(s)
Body Composition , Absorptiometry, Photon/methods , Brazil , Electric Impedance , Humans , Reproducibility of ResultsABSTRACT
Abstract Objective: To present an updated and evidence-based guideline for the use of dual-energy x-ray absorptiometry (DXA) to assess body composition in clinical practice. Materials and methods: This Official Position was developed by the Scientific Committee of the Brazilian Association of Bone Assessment and Metabolism ( Associação Brasileira de Avaliação Óssea e Osteometabolismo , ABRASSO) and experts in the field who were invited to contribute to the preparation of this document. The authors searched current databases for relevant publications in the area of body composition assessment. In this second part of the Official Position, the authors discuss the interpretation and reporting of body composition parameters assessed by DXA and the use of DXA for body composition evaluation in special situations, including evaluation of children, persons with HIV, and animals. Conclusion: This document offers recommendations for the use of DXA in body composition evaluation, including indications, interpretation, and applications, to serve as a guiding tool in clinical practice and research for health care professionals in Brazil.
ABSTRACT
Considering ethnic and anthropometric differences, it is important to obtain specific normative data on body composition (BC) for each population. The objectives of this study were to obtain the normative curve for the BC of Brazilian men and to compare them to the North American male population. A total of 403 healthy Brazilian men 20 years and older were included in the study. Data on concomitant diseases and physical activity were investigated using a structured questionnaire. Conditions that could affect lean and fat mass were excluded. BC was assessed via whole-body dual-energy X-ray absorptiometry (DXA) using a GE-Lunar device. Significance level was set as p < 0.05. Mean age and body mass index (BMI) were 46.0 ± 17.9 years and 26.2 ± 3.14 kg/m2, respectively. Mean skeletal mass index (SMI), appendicular lean mass by BMI (ALMBMI), and fat mass index (FMI) were 8.38 ± 0.85, 0.949 ± 0.138, and 6.87 ± 2.43 kg/m2, respectively. There were negative associations among SMI (p < 0.001), ALMBMI (p < 0.001), and FMI (p = 0.002) with age. Comparison with the National Health and Nutrition Examination Survey (NHANES) III data, originally performed with a Hologic device, showed that Brazilian men had lower FMI and BF. This difference was minimized after converting the NHANES results to the GE-Lunar database. Brazilian men had lower SMI than American men measured in NHANES III. FMI was less influenced by ethnicity than by BMI, and it could be used as a standard measure for assessing fat excess or adiposity. Our data suggest that conversion to each specific manufacturer's database should be performed to minimize differences in body composition between populations.
ABSTRACT
Objetivo: avaliar a freqüência de lúpus neonatal, prematuridade, natimortalidade, abortamento e baixo peso em gestações de pacientes com LES atendidas num serviço terciário. Métodos: estudo retrospectivo dos atendimentos a pacientes com LES realizados no centro obstétrico do Hospital São Paulo/Unifesp/ EPM, entre novembro de 1991 e abril de 2003. Os dados clínicos e laboratoriais referentes à mãe e fetos foram obtidos através da revisão de prontuários médicos. Resultados: foram identificadas 60 mulheres com LES que tiveram 75 gestações. A média de idade das mães por ocasião das gestações foi de 27,1± 6,1 anos e a mediana de tempo da doença foi de 48 meses. Duas gestantes necessitaram de diálise peritoneal. Sessenta e três pacientes fizeram uso de prednisona, 4 pacientes receberam pulsoterapia com solumedrol e 2 receberam azatioprina durante a gravidez. No primeiro trimestre da gestação, 6 pacientes haviam feito uso de difosfato de cloroquina e 2 utilizaram hidroxicloroquina. Uma paciente que havia recebido pulso de ciclofosfamida e outra que havia utilizado metotrexato desconhecendo a gravidez evoluíram com abortamento fetal espontâneo. Foram encontrados 13 óbitos intra-uterinos e 7 abordamentos. O parto foi prematuro em 57 das gestações e a média de tempo de gestação foi de 35 semanas. A média de peso ao nascer foi de 2.332±961g (variando de 525 a 3.620g). Foram detectados 5 casos de lúpus neonatal (8,9), sendo um bloqueio cardíaco congênito (BCC) com óbito intrauterino na 29a semana e 3 plaquetopenias associadas à anti-Ro/ SSA e 1 neutropenia associada ao anti-RNP. Com exceção do caso com BCC, estes anticorpos foram detectados no soro materno e no sangue do cordão umbilical. Ao final do estudo, foram detectados dois óbitos de recém-nascidos, com 9 e 130 dias de vida, em decorrência de complicações com a prematuridade. Conclusões: com relação à literatura, este estudo mostrou similar prevalência de perda fetal (aborto e óbito intra-uterino), entretanto, a freqüência de prematuridade foi maior que a média referida em outros trabalhos. Manifestações hematológicas do lúpus neonatal, como leucopenia e plaquetopenia foram observadas em freqüência maior do que a referida na literatura. Por serem transitórias e assintomáticas, estas alterações podem ter sido subdiagnosticadas.
