Nutritional status in sick children and adolescents is not accurately reflected by BMI-SDS.

OBJECTIVE: Nutritional status provides helpful information of disease severity and treatment effectiveness. Body mass index standard deviation scores (BMI-SDS) provide an approximation of body composition and thus are frequently used to classify nutritional status of sick children and adolescents. However, the accuracy of estimating body composition in this population using BMI-SDS has not been assessed. Thus, this study aims to evaluate the accuracy of nutritional status classification in sick infants and adolescents using BMI-SDS, upon comparison to classification using percentage body fat (%BF) reference charts. DESIGN: BMI-SDS was calculated from anthropometric measurements and %BF was measured using dual-energy x-ray absorptiometry (DXA) for 393 sick children and adolescents (5 months-18 years). Subjects were classified by nutritional status (underweight, normal weight, overweight, and obese), using 2 methods: (1) BMI-SDS, based on age- and gender-specific percentiles, and (2) %BF reference charts (standard). Linear regression and a correlation analysis were conducted to compare agreement between both methods of nutritional status classification. %BF reference value comparisons were also made between 3 independent sources based on German, Canadian, and American study populations. RESULTS: Correlation between nutritional status classification by BMI-SDS and %BF agreed moderately (r (2) = 0.75, 0.76 in boys and girls, respectively). The misclassification of nutritional status in sick children and adolescents using BMI-SDS was 27% when using German %BF references. Similar rates observed when using Canadian and American %BF references (24% and 23%, respectively). CONCLUSIONS: Using BMI-SDS to determine nutritional status in a sick population is not considered an appropriate clinical tool for identifying individual underweight or overweight children or adolescents. However, BMI-SDS may be appropriate for longitudinal measurements or for screening purposes in large field studies. When accurate nutritional status classification of a sick patient is needed for clinical purposes, nutritional status will be assessed more accurately using methods that accurately measure %BF, such as DXA.

Actual diet and nutritional deficiencies status in children on peritoneal dialysis at the Vietnam National Hospital of Pediatrics.

Nutrition is essential for children with end-stage renal disease, especially for those suffering from peritoneal dialysis (PD). Although the number of PD children has increased annually at the Vietnam National Hospital of Pediatrics, studies about the diet and nutritional deficiencies status of PD children is still limited. The aim of this study was to describe the actual diet and status of nutritional deficiencies of PD patients. This cross-sectional study was conducted on 31 PD children aged 2-15 years old using the 24-h dietary recall and biochemical parameters in blood (albumin, hemoglobin, calcium, sodium, potassium, and chloride). The energy intake was lowest in children over 13-year-old with only 32.9% of dietary reference intakes (DRIs). Carbohydrate intake among 10-15-year-old children was 38.1% of DRIs. Daily consumption of sodium was 65.6% and 33%-35% of DRIs for children under and over three-year-old, respectively. In comparison with DRIs, daily consumption of magnesium, iron, and calcium of over 10-year-old children was lower than that of younger children. In terms of vitamins, B-group vitamins, Vitamin C achieved the recommended levels except Vitamin A (63.0%) and Vitamin D (20.0%). The prevalence of children with serum albumin concentration lower than the normal range was 45.2% and prevalence of anemia was 51.6%. The proportion of children with decreased plasma calcium, sodium, and potassium levels was 83.8%, 77.4%, and 12.9%, respectively. PD children's diet lacks energy, protein, lipid, carbohydrate, as well as micronutrients. The prevalence of nutritional deficiencies is remarkably high in PD children.

Validity of two physical activity questionnaires (IPAQ and PAQA) for Vietnamese adolescents in rural and urban areas.

BACKGROUND: Although physical activity is recognised to be an important determinant of health and nutritional status, few instruments have been developed to assess physical activity in developing countries. The aim of this study was to compare the validity of the short form of the International Physical Activity Questionnaire (IPAQ) and a locally adapted version of the Physical Activity Questionnaire for Adolescents (PAQA) for use in school going adolescents in rural and urban areas in Vietnam. METHODS: Sixteen year old adolescents from rural areas (n = 137) and urban areas (n = 90) completed the questionnaires in 2006. Test-retest reliability was assessed by comparing registrations after 2 weeks. Criterion validity was assessed by comparison with 7 days continuous accelerometer logging. Validity of the two methods was assessed using Spearman correlation coefficient, intra class correlation coefficients (ICC) and Kappa statistics. RESULTS: Reliability of both questionnaires was poor for both the IPAQ (ICC = 0.37) and the PAQA (ICC = 0.40). Criterion validity of both questionnaires was acceptable and similar for the IPAQ (rho = 0.21) and the PAQA (rho = 0.27) but a significantly lower validity was observed in rural areas. Both forms poorly estimated time spent on light, moderate and vigorous physical activity. Agreement of both questionnaires to classify individuals was also low but the IPAQ performed better than the PAQA. CONCLUSION: Both questionnaires have a similar and overall poor validity to be used as a population instrument in Vietnam. Low reliability and classification properties in rural areas call for further research for specific use in such settings.

Use of bioelectrical impedance analysis and anthropometry to measure fat-free mass in children and adolescents with Crohn disease.

OBJECTIVES: To investigate the precision of published prediction equations for fat-free mass (FFM) from bioimpedance measurements in children with Crohn disease using dual-energy X-ray absorptiometry (DXA) as an in vivo gold standard. METHODS: Fat-free mass of 49 white boys and girls ages 7.3 to 16.9 y suffering from Crohn disease was measured by DXA. Body weight, height and bioimpedance measurements were also collected. FFM measured by DXA (FFM(DXA)) was compared with FFM predicted by the only 5 published prediction equations available for children and adolescents. An equation was developed for predicting FFM and was validated using a bootstrap method. RESULTS: When correlating predicted FFM with FFM(DXA), Schaefer's equation showed the highest R2 (0.950), the smallest standard error of estimate (SEE) (2.05 kg) and the smallest percentage error (0.28%). Our prediction equation for estimating FFM was FFM = 0.652 Ht2/Z + 0.0385 Wt + 0.586 Age - 0.327, R2 = 0.951, SEE = 2.08, P < 0.0005, where Ht2/Z is the impedance index in cm2/ohm, Wt is body weight in kilograms, age is in years. R2 value from bootstrap method was 0.950 +/- 0.01 (95% confidence interval 0.927-0.968), indicating an acceptable validation of the derived formula. CONCLUSIONS: The formula of Schaefer is the best for predicting FFM. The present study provides a new prediction equation for estimating FFM in children with Crohn disease that may be used in clinical settings in which more sophisticated body composition measuring equipments are not available.

Eating out of home in Vietnamese adolescents: socioeconomic factors and dietary associations.

BACKGROUND: Out-of-home (OH) eating in developed countries is associated with suboptimal dietary intakes, but evidence is scarce on the situation in developing countries. OBJECTIVE: The objective of this study was to determine the nutritional contribution of OH eating and related socioeconomic determinants in Vietnamese adolescents. DESIGN: A 24-h recall was used to collect food intake data in a cross-sectional study of 1172 adolescents living in urban and rural areas. Multilevel analysis compared the mean daily intakes of energy, energy density, energy from fat, food groups, vitamin A, iron, and zinc in low, middle, and high consumers of OH food. Socioeconomic associations of OH eating were analyzed in a subsample of 870 adolescents. RESULTS: OH foods contributed 42% of fruit and vegetables, 23% of sodium, 21% of energy, 21% of vitamin A, 21% of iron, and 21% of zinc consumed per day. OH eating was negatively associated with total energy intake and energy density and positively associated with dietary diversity, energy contribution from fat, and consumption of sugar products. In rural areas, OH eating was positively associated with iron, fruit, meat, poultry, and offal intake. Female sex (P < 0.001), residence in urban areas (P < 0.001), and amount of pocket money (P < 0.001) were positively associated with consumption of OH foods. CONCLUSIONS: OH eating added a number of desirable foods and nutrients but was also associated with higher consumption of energy from fat and sugar products. Independent of household wealth and locality, pocket money and sex are important determinants of OH eating.

Body composition of preterm infants measured during the first months of life: bioelectrical impedance provides insignificant additional information compared to anthropometry alone.

UNLABELLED: Detailed knowledge of body composition in preterm neonates during their later postnatal period may be important for the treatment process. However, little consideration has been given to test whether bioelectrical impedance analysis (BIA) is a useful bedside method to predict fat-free mass (FFM). The aim of the study is to assess whether BIA is a bedside method to measure FFM in preterm neonates. FFM of 118 white subjects (51 males, 67 females), mean gestational age of 30.1+/-3.1 weeks and birth weight of 1.26+/-0.47 kg, was measured at a gestational age of 38.6+/-3.8 weeks and actual body weight of 2.6+/-0.54 kg using dual energy X-ray absorptiometry (FFM(DXA)). Weight (W), height (Ht), and bioelectric impedance (I) measurements were collected. Multiple regression analysis was performed to develop prediction equations to estimate FFM with impedance index (Ht(2)/I, cm(2)/Omega) and W (kg) as predictor variables. Bootstrap analysis was performed for validating the derived prediction equations. Correlations between FFM(DXA) and weight were 0.96, 0.98, and 0.97 in boys, girls, and both sexes, respectively. Those between FFM(DXA) and Ht(2)/I were: 0.73, 0.81, and 0.79. Equations used to predict FFM (kg) were for boys: FEM = 0.05Ht(2)/I + 0.68W + 0.40(R2 = 0.919) and for girls: FFM = 0.04Ht(2)/I + 0.71W + 0.29(R2 = 0.957). CONCLUSIONS: In preterm neonates, weight is a more effective predictor of FFM than impedance index. The study provides a bedside procedure for estimating FFM, mainly based on anthropometric parameters rather than BIA.