Assessment of body composition measured by bioelectrical impedance in children

Bioelectorical impedance methods have been found to be a valid and reliable way of estimating per cent body fat (%BF) in adults. We applied them to healthy children and compared them with conventional anthropometry methods. One thousand two hundred and sixteen children participated in this study. Impedance and skinfold thickness were measured, and %BF was estimated using these values. Bodyweight and height were measured, and per cent obesity (%OB) and body mass index (BMI) were obtained. The values of %BF by the bioelectrical impedance method (%BFi) were 8.6 ± 4.0% in the junior male group, 14.2±2.8% in the junior female group, 7.9±4.7% in the senior male group and 16.1 ±2.9% in the senior female group. The % BFi correlated strongly with skinfold thickness, %OB and BMI. Thus %BFi correlated strongly with variables from conventional methods. It was concluded that it is a reliable way of assessing lipid storage in children.     

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??Objective To analyze characteristics of body composition and the relativity on percentage of body fat??PBF????fat mass??FM????lean mass??LM?? with the local and systemic bone mineral density??BMD?? of low weight and obese children aged from 5 to 7 years old. Methods A total of 311 children aged from 5 to 7 years old were divided into three groups according to gender and body mass index??BMI????the low weight group??the control group and the obesity group??who came to Department of Child Healthcare of Shengyang Children’s Hospital for roution physical examination from February 2010 to February 2012 were selected as the subjects of the study. The body composition were measured by dual energy X-ray absorptiometry??DEXA??. Data had been compared between groups and correlation had been analysised among PBF??FM??LM and BMD. Results In obesity group?? the LM??upper limbs??lower limbs and systemic BMD in boys were significantly higher than those in girls??P??0.05??. In control group??girls’s PBF??FM were significantly higher than boys’. LM?? upper limbs?? lower limbs and systemic BMD in girls were lower than those in boys??P??0.05??. In low weight group??when FM was controlled??there was positive correlation between LM and BMD??P??0.01??. When LM was controlled??there was positive correlation among PBF??LM and lower limbs BMD in obesity girls??P??0.05??. When FM was controlled??there was significantly positive correlation between LM and lower limbs BMD??P??0.01??. When FM was controlled??there was positive correlation between LM and lower limbs BMD in obesity boys??P??0.05????When LM was controlled??there was positive correlation among PBF??FM and truncal BMD??P??0.05??. Conclusion The proportion is different from controls in low weight and obese children?? and the contribution to BMD is different. It should not only pay attetion to the change of body weight??but also pay attetion to the changes of PBF??FM??LM in body composition??so as to promote the healthy development of the bone.     

Body fat, abdominal fat and body fat distribution related to cardiovascular risk factors in prepubertal children

Aim: We analysed whether total body fat (TBF), abdominal fat and body fat distribution are associated with higher composite risk factor scores for cardiovascular disease (CVD) in young children. Methods: Cross‐sectional study of 238 children aged 8–11 years. TBF and abdominal fat mass (AFM) were measured by Dual‐Energy X‐Ray Absorptiometry. TBF was expressed as a percentage of body weight (BF%). Body fat distribution was calculated as AFM/TBF. Maximal oxygen uptake (VO_2PEAK), systolic and diastolic blood pressure (SBP, DBP), and resting heart rate (RHR) were measured. Mean arterial pressure (MAP) and pulse pressure (PP) were calculated. Left atrial diameter (LA) was measured, and left ventricular mass (LVM) and relative wall thickness (RWT) were calculated. Z‐scores were calculated. Sum of z‐scores for SBP, DBP, MAP, PP, RHR, LVM, LA, RWT and ?VO_2PEAK was calculated in boys and girls, separately, and used as composite risk factor score. Results: Pearson correlations between ln BF%, ln AFM and AFM/TBF versus composite risk factor score for boys were r = 0.56, r = 0.59 and r = 0.48, all p < 0.001, and for girls r = 0.45, r = 0.50 and r = 0.48, all p < 0.001. Conclusion: Total body fat, abdominal fat and body fat distribution were all associated with higher composite risk factor scores for CVD in young children.     

Bioelectrical impedance for measuring percentage body fat in young persons with Down syndrome: validation with dual‐energy absorptiometry

Aim: Children with Down syndrome have an increased prevalence of obesity, although there is little work describing body composition in this population. The aims of this study were to accurately measure body fat in children with Down syndrome and to identify which existing algorithm best predicts percentage body fat in this population. Methods: Seventy children with Down syndrome had anthropometric, bioelectrical impedance analysis (BIA) and dual‐energy X‐ray absorptiometry (DXA) data collected to calculate percentage body fat (PBF). Pearson correlations were carried out to assess the relationships of various methods for measuring body fat and Bland–Altman plots to assess systematic error. Results: Mean PBF was 30.5% for girls and 22.5% for boys. A total of 38% of girls and 23% of boys were obese according to international criteria. PBF as determined by DXA correlated well with PBF by BIA in both girls and boys (r = 0.91 and 0.89, respectively, p < 0.001). Conclusion: There are high rates of obesity in children with Down syndrome. BIA can be used to accurately determine adiposity in this population. We recommend the use of the Schaeffer algorithm for calculation of PBF in children with Down syndrome.     

A 3‐year longitudinal study of skeletal effects and growth in children after kidney transplantation

This prospective study investigated growth and skeletal development for 3 years after kidney transplantation in pediatric patients, 3.4‐15.0 years of age. Growth, BMD, bone resorption markers (CTX and TRACP5b), bone formation markers (PINP, ALP, and osteocalcin), PTH, and vitamin D were assessed at start, 3, 12, and 36 months after transplantation. Median GFR was 63 (range 37‐96) mL/min/1.73 m² after 3 years. The median height SDS increased from ?1.7 to ?1.1, and median BMI SDS increased from ?0.1 to 0.6 over 3 years, which shows that transplantation had a favorable outcome on growth. Fat mass increased after transplantation at all time points, whereas lean mass increased after 1 year and 3 years. Total BMC increased at all time points. No changes were observed for total BMD. Bone resorption markers decreased initially after 3 months and remained stable throughout the study, whereas the bone formation markers decreased initially, but successively increased over the study period. In conclusion, this study demonstrates that height SDS and BMI SDS increased, along with the increased formation markers that reveal a positive bone acquisition after kidney transplantation, which was reflected by the significant increase in total body BMC.     

Body composition and bone mass in survivors of childhood cancer

BACKGROUND: The number of survivors of childhood cancer has increased. Several studies in children and adults have shown relationships between lean mass (LM), fat mass (FM), and bone mineral content (BMC). The objective of the study was to examine the association between body composition and bone mass in young survivors of childhood cancer. METHODS: Sixty-eight postpubertal participants (31 females and 37 males) aged between 15.5 and 27 years who were at least 5 years after completion of treatment for leukemia (n = 30), lymphoma (n = 28), or solid tumors (n = 10) were studied. Anthropometry was performed and dual energy X-ray absorptiometry (DXA) was used to assess BMC in the total body (T) and lumbar spine (S), FM, and LM. RESULTS: There were no observed differences in age or time for cessation of treatment. Body mass index (BMI) was a strong determinant of bone mass in both sexes. TBMC correlated positively with LM (males r = 0.9 and females r = 0.76; P < 0.0001, respectively) and with FM (r = 0.54; P < 0.01 in males and r = 0.8; P < 0.00001 in females). SBMC correlated with LM in both sexes (in males r = 0.77 and in females r = 0.64; P < 0.0001, respectively) but only in females, SBMC also correlated positively with FM (r = 44 P = 0.03). There were no differences between patients who received radiation and those who did not. CONCLUSIONS: The associations between bone mass and body composition differ by sex and skeletal site, however, they are similar in survivors of childhood cancer and compared to healthy individuals during growth. Further prospective research is needed in cancer survivors to determine the long-term effect of anti-cancer therapy on body composition and bone mass.     

Body fatness and serum lipids of 11-year-old Chinese children

It has been suggested that distribution of body fat has a stronger bearing on health risk than total body fat. Magnetic resonance imaging (MRI) was used to examine the distribution of fat and correlated with body fat assessed by the usual clinical methods-weight, weight-for-height, body mass index (BMI), triceps and subscapular skinfold thickness in 11-y-old Chinese children. Lipid profiles were used as indicators for coronary risk. Eighty-eight subjects had body fat distribution estimated by MRI, while 49 had serum lipids measured. Anthropometric parameters correlated significantly with total fat at the umbilical level measured by MRI (weight: r = 0.90 in boys, 0.75 in girls; BMI: r = 0.94 in boys, 0.87 in girls; percent median weight-for-height: r = 0.90 in boys, 0.79 in girls, triceps skinfold thickness: r = 0.89 in boys, 0.90 in girls; subscapular skinfold thickness: r = 0.93 in boys, 0.88 in girls). Obese subjects had proportionally less visceral fat than subcutaneous fat at umbilical level. Using stepwise multiple regression, predictive factors for high-density lipoprotein cholesterol were BMI in boys and breast-staging in girls. For triglycerides, it was genital staging in boys and for total cholesterol, it was breast-staging in girls. Visceral fat was not a significant determinant of serum lipids.