Official Position of the Brazilian Association of Bone Assessment and Metabolism (ABRASSO) on the evaluation of body composition by densitometry—part II (clinical aspects): interpretation, reporting, and special situations

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.

Impaired bone mineral accrual in prepubertal HIV-infected children: a cohort study

ABSTRACT OBJECTIVE: To evaluate bone mass accrual and determine the influence of clinical, anthropometric, dietary and biochemical parameters on bone mass. METHODS: A cohort study including 35 prepubertal HIV-infected children, between 7 and 12 years, attended at a referral center. At time 1 (T1) and time 2 (T2), patients were assessed according to clinical, anthropometric, dietary, biochemical parameters and bone mineral density (BMD). At T2, patients were divided into prepubertal and pubertal. RESULTS: Despite the increase in bone mass absolute values, there was no improvement in lumbar spine BMD (LSBMD) Z-score (p = 0.512) and worsening in total body BMD (TBMD) Z-score (p = 0.040). Pubertal patients (n = 19) showed higher bone mineral content (BMC) (p = 0.001), TBMD (p = 0.006) and LSBMD (p = 0.002) compared to prepubertal patients. After multivariate linear regression analysis, the predictors of bone mass in T1 were age, BMI and HAZ-scores for BMC; BMI Z-score, adequate serum magnesium concentration and dietary calcium intake for TBMD; adequate serum concentration of magnesium, BMI and HAZ-scores for LSBMD. In T2, age, total body fat and lean body mass (kg) for BMC; BMI Z-score and puberty for TBMD; dietary fat intake, BMI Z-score for BMD and puberty for LSBMD. CONCLUSION: HIV-infected children have compromised bone mass and the presence of puberty seems to provide suitability of these parameters. Adequate intake of calcium and fat appears to be protective for proper bone mass accumulation factor, as well as monitoring nutritional status and serum magnesium concentration.

Body Composition Changes and Predictors of Lipodystrophy in a Cohort of Pre-pubertal HIV- infected Children.

Aim: To evaluate body composition changes in HIV-infected patients and to identify the predictors of lipodystrophy over time. Methods: A cohort study, evaluated over two and a half years (Time 1: T1; Time 2: T2), including prepubertal HIV-infected children of both genders, between 7-12 years of age. Patient’s data such as transmission, use of prophylaxis for vertical HIV transmission, clinical and immunological classification of disease and current antiretroviral therapy were derived from the medical records. At T1, only subjects with pubertal stage 1 were included. Clinical, anthropometric, body composition and biochemical data were assessed. Patients were divided into two groups: with (LD+) and without lipodystrophy (LD-). Results: A total of 40 patients were enrolled, and 35 patients completed the study. Mean (SD) age was 9.6 (1.1) and 11.6 (1.2) years at T1 and T2, respectively. At T2, 16 (45.7%) children remained prepubertal. LD+ group (n = 8) showed a higher prevalence of short stature (p = 0.008) in T1; higher insulin (p = 0.010) and HOMA-IR (p = 0.013) and reduction of triceps skinfold thickness (p = 0.026) at T2. In both times, we observed lower concentrations of HDLc (p = 0.027), higher values of trunk to arm ratio (p = 0.002, p = 0.001) and lower values of limb to trunk ratio (p = 0.001) and gynoid fat (p= 0.001) in LD+ group. At T1, predictors of lipodystrophy were short stature (OR = 46.198, p = 0.019) and limb to trunk ratio (OR = 0.00009, p = 0.011); in T2, waist circumference (OR = 1.199, p = 0.025) and HDLc (OR = 0.835, p = 0.015). Presence of lipodystrophy was determinant of high insulin levels at T2. Conclusion: In a short period, LD+ group had significant changes in body fat distribution and also biochemical alterations associated to lipodystrophy syndrome.

Assessment of antioxidants status and superoxide dismutase activity in HIV-infected children

Objective: This study aims to assess the nutritional status of selenium, copper and zinc; and also the erythrocyte superoxide dismutase activity of HIV-infected children compared to a control group. Methods: A cross-sectional study was carried out with prepubertal HIV-infected children (n = 51) and their healthy siblings (n = 32). All biochemical measurements including plasma selenium, serum copper levels, serum and erythrocyte zinc levels and erythrocyte super-oxide dismutase activity were evaluated according to dietary, clinical and biochemical parameters. Results: Compared to the control group, the HIV-infected children had lower z-score values for height-for-age (p = 0.0006), higher prevalence of stunting (11.8%) (p = 0.047), lower selenium levels (p = 0.0006) and higher copper levels (p = 0.019). No difference was found concerning superoxide dismutase activity (p > 0.05). The HIV-infected group presented a higher proportion (45.1%) of children with zinc intakes below the estimated average requirement (p = 0.014); however, no association with zinc biochemical parameters was found. Conclusion: HIV-infected children have an inadequate selenium and copper nutritional status, which could influence the progression to AIDS. An adequate micronutrient status could improve the clinical conditions in these patients and minimize free radical production and cellular oxidative stress. .

Body composition and lipodystrophy in prepubertal HIV-infected children

OBJECTIVE: To identify lipodystrophy in prepubertal HIV-infected children using anthropometric parameters and body composition assessment. METHODS: Cross-sectional study including 40 prepubertal HIV-infected children of both genders seen at the Care Center of the Division of Pediatric Infectious Diseases - Universidade Federal de São Paulo, São Paulo city, Brazil, was carried out from August to December 2008. Age, clinical and immunological status, prophylaxis, transmission and highly active antiretroviral therapy were recorded. Body mass index z-score and height-for-age z-score were calculated to characterize the nutritional status. Circumferences were measured with flexible tape and skinfolds were assessed by an adipometry. Fat mass and lean mass were determined by dual-energy X-ray absorptiometry. Presence of clinical signs of lipodystrophy was assessed by a trained clinician. Data were analyzed using SPSS 12.0 software. RESULTS: The mean age and standard deviation were 9.8 (1.2) years, 50% were girls and 82.5% children from B and C categories. Clinical lipodystrophy and dislypidemia were present in 27.5% and 70%, respectively. The trunk to arm ratio and the limb to trunk ratio had positive association with lipodystrophy. Patients with lipodystrophy had short stature, higher triglycerides values and lower HDL-cholesterol. CONCLUSION: The ratios obtained by skinfolds and dual-energy X-ray absorptiometry measurements can be considered as indicators of preclinical lipodystrophy. The cutoff points have not been determined yet; however, continuous assessment may be useful to identify early body composition changes.

Estado nutricional de crianças e adolescentes hospitalizados em enfermaria de cirurgia pediátrica / Nutritional status of children and adolescents hospitalized at the pediatric surgery unit

OBJETIVO: Avaliar o estado nutricional, o tempo de internação e as especialidades clínicas de pacientes internados na enfermaria de Cirurgia Pediátrica do Hospital São Paulo da Unifesp-EPM. MÉTODOS: Estudo transversal retrospectivo, com 749 crianças e adolescentes de ambos os gêneros acompanhados por equipe interdisciplinar durante o período de agosto de 2007 a julho de 2008. Foram coletados dados antropométricos, dias de internação e procedimento cirúrgico segundo a especialidade. Para a classificação do estado nutricional, utilizou-se o escore Z do índice de massa corporal (Z IMC) e da estatura/idade (Z E/I) segundo a curva da Organização Mundial de Saúde (OMS, 2007). As crianças foram classificadas segundo diagnóstico estabelecido previamente à cirurgia. Utilizou-se o programa STATA 8.0 para análise dos dados e aplicou-se o teste ANOVA e comparações múltiplas de Bonferroni, considerando-se significante p<0,05. RESULTADOS: A mediana de idade foi sete anos (0 a 18), predominando o gênero masculino (59 por cento) e as internações para cirurgia otorrinolaringológica (18 por cento). Dos pacientes internados, 66 por cento tinham estatura adequada para idade, 43 por cento eutróficos e 31 por cento obesos/sobrepeso. Os pacientes desnutridos permaneceram mais dias internados quando comparados aos obesos/sobrepeso (7,2 versus 4,1 dias; p=0,035). Os lactentes apresentaram maior tempo de internação (p=0,006) e menor valor de Z IMC, comparados aos outros grupos etários (p=0,001). Os lactentes com programação de cirurgia cardíaca apresentaram Z IMC menor em relação às demais especialidades (p=0,002). CONCLUSÕES: O perfil dos pacientes internados condiz com a atual transição nutricional, aumento da prevalência de obesidade concomitante à desnutrição. Entretanto, a desnutrição ainda constitui fator agravante para a permanência hospitalar.

OBJECTIVE: To evaluate the nutritional status, duration of hospital stay and clinical specialties of patients hospitalized in the Pediatric Surgery Unit of São Paulo Hospital, Unifesp-EPM. METHODS: This cross-sectional retrospective study enrolled 749 children and adolescents of both genders admitted to the Pediatric Surgery Unit during the period of August 2007 to July 2008. The following data were collected: anthropometric variables, duration of hospital stay and surgical procedures. For nutritional status classification, the Z score for body mass index (Z BMI) and height-for-age (Z H/A) were used according to the World Health Organization growth chart (WHO, 2007). The children were classified according to the surgical procedures performed. Results were compared by ANOVA followed by Bonferroni multiple comparisons test, being significant p<0.05. Statistical analysis was carried out through STATA 8.0 software. RESULTS: Patients' mean age was seven years old (0 to 18), 59 percent were males and 18 percent had ear, neck or throat surgery. Among the hospitalized patients, 66 percent had appropriated height for age, 43 percent were eutrophic and 31 percent obese/overweight. The malnourished patients presented longer hospital stay than the obese/overweight patients (7.2 versus 4.1 days; p=0,035). Infants had prolonged hospital stay (p=0,006) and less Z BMI values in comparison to the other age groups. (p=0,001). Infants that needed cardiac surgery presented lower Z BMI in relation to the others (p=0,002). CONCLUSIONS: The patients profile in the Pediatric Surgery Unit followed the nutritional pattern observed in Brazil, with increasing prevalence of obesity together with malnutrition. However, malnutrition is still an aggravating factor for prolonged hospital stay.