Body composition analysis by dual-energy X-ray absorptiometry in young preschool children

Effective dose of propofol combined with intravenous esketamine for smooth flexible laryngeal mask airway insertion in two distinct age groups of preschool children

BACKGROUND

There is limited research on the combined use of propofol and esketamine for anesthesia induction during flexible laryngeal mask airway (FLMA) in pediatric patients, and the effective dosage of propofol for FLMA smooth insertion remains unclear. We explored the effective dose of propofol combined with intravenous esketamine for the smooth insertion of FLMA in two distinct age groups of preschool children.

METHODS

This is a prospective, observer-blind, interventional clinical study. Based on age, preschool children scheduled for elective surgery were divided into group A (aged 1-3 years) and group B (aged 3-6 years). Anesthesia induction was started with intravenous administration of esketamine (1.0 mg.kg- 1) followed by propofol administration. The FLMA was inserted 2 min after propofol administration at the target dose. The initial dose of propofol in group A and group B was 3.0 mg.kg- 1 and 2.5 mg.kg- 1, respectively. The target dose of propofol was determined with Dixon's up-and-down method, and the dosing interval of propofol was 0.5 mg.kg- 1. If there was smooth insertion of FLMA in the previous patient, the target dose of propofol for the next patient was reduced by 0.5 mg.kg- 1; otherwise, it was increased by 0.5 mg.kg- 1. The median 50% effective dose (ED50) for propofol was estimated using Dixon's up-and-down method and Probit analysis, while the 95% effective dose (ED95) was estimated through Probit analysis. Vital signs and adverse events during induction were recorded.

RESULTS

Each group included 24 pediatric patients. Using Dixon's up-and-down method, the ED50 of propofol combined with esketamine for smooth insertion of FLMA in group A was 2.67 mg.kg- 1 (95%CI: 1.63-3.72), which was higher than that in group B (2.10 mg. kg- 1, 95%CI: 1.36-2.84) (p = 0.04). Using Probit analysis, the ED50 of propofol was calculated as 2.44 (95% CI: 1.02-3.15) mg.kg- 1 in group A and 1.93 (95% CI: 1.39-2.32) mg.kg- 1 in group B. The ED95 of propofol was 3.72 (95%CI: 3.07-15.18) mg.kg- 1 in group A and 2.74 (95%CI: 2.34-5.54) mg.kg- 1 in group B. In Group B, one pediatric patient experienced laryngospasm.

CONCLUSION

The effective dose of propofol when combined with intravenous esketamine for smooth insertion of FLMA in children aged 1-3 years is 2.67 mg.kg- 1, which is higher than that in children aged 3-6 years (2.10 mg. kg- 1).

TRIAL REGISTRATION

Chinese Clinical Trial Registry Center (Registration Number: ChiCTR2100044317; Registration Date: 2021/03/16).

Serum phospholipid fatty acids are associated with bone mass in healthy 4-years-old children

BACKGROUND

Fatty acids are involved in bone development but knowledge in children is limited. The aim of this study was to investigate bone mass and mineral density in healthy preschool children in relation to fatty acids.

MATERIAL AND METHODS

In 111 healthy 4-yrs-old children (20 % overweight) bone was analysed by dual X-ray absorptiometry and serum phospholipid fatty acid by gas chromatography. Fat intake was calculated from 7 days self-reported dietary records and food frequency questionnaire.

RESULTS

Total bone mass content (BMC) and mineral density (BMD) differed by sex in normal weight, but not in overweight children showing generally higher bone mass density than children with normal weight. Linoleic acid intake was strongly correlated to BMC and femoral BMD in normal weight children. Serum concentration of docosahexaenoic acid correlated positively to BMD in all children (p = 0.01), but linoleic and arachidonic acids, and monounsaturated fatty acids showed diverging associations with bone in normal weight and overweight children.

CONCLUSION

Serum phospholipid DHA was associated with bone density. Other fatty acids associations to bone sites differed in overweight children, analogue to the pattern in healthy 8-yrs-old.The finding need to be confirmed longitudinally and in a larger group of overweight individuals.

Assessment of Bone Health Using Dual-Energy X-Ray Absorptiometry (DEXA) And Its Association with Dietary Intakes, Serum Vitamin D Levels, and Anthropometric Measures in Healthy Urban Preschool Children

OBJECTIVES

To generate reference data for bone mineral content (BMC) and bone mineral density (BMD) measures among apparently healthy children aged 4-5 y and to study the relationship of BMC and BMD with age, sex, anthropometric measures, dietary intakes, and serum vitamin D levels.

METHODS

This cross-sectional study was conducted among 219 urban preschool children, aged 4.0-5.11 y. Bone health (BMC and BMD) was measured using dual energy X-ray absorptiometry (DEXA). Anthropometric parameters were measured using standard methodology. The 24-h dietary recall method was used to assess the dietary intake of the children. Serum vitamin D levels were assessed using the ELISA kit method. Percentiles for BMC and BMD for each age and sex were constructed using the lambda-mu-sigma (LMS) method.

RESULTS

The mean BMD and BMC among children was 0.75 ± 0.04 g/cm2 and 544.9 ± 87.6 g, respectively, and were significantly different by age and sex category. The BMC and BMD values of boys and girls increased with age, with boys having significantly higher values. A significant positive correlation was observed for BMC and BMD with anthropometric measures and dietary intake of calcium, phosphorous, protein, zinc, and B vitamins.

CONCLUSION

This study developed smoothed percentile curves for BMC and BMD in preschool children, which could be used as reference values for children from India.

Effect of body mass index on soft tissues in adolescents with skeletal class I and normal facial height

Background

The evaluation of soft tissues in patients undergoing orthodontic treatment plays a critical role in diagnosis and treatment planning. This study aims to evaluate the effect of body mass index (BMI) on facial soft tissues in skeletal Class I patients with normal vertical growth.

Methods

The study included 72 patients with a normal vertical growth pattern (SN-GoGn 26-38°) and skeletal Class I (ANB 2‒4°) malocclusion. According to their BMI (kg/m2) values, the patients were divided into three groups of 24 individuals each: underweight (>5th percentile) (13 females, 11 males; mean age, 11.58 ± 1.95 years), normal weight (5‒85th percentile) (12 females, 12 males; mean age, 11.54 ± 1.95 years), overweight (85‒95th percentile) (12 females, 12 males; mean age, 11.62 ± 2.01 years). Soft tissue thickness and height measurements were made on lateral cephalometric radiographs.

Results

In all soft tissue thickness measurements, except for the nasion, the overweight weight group had higher values. In comparing the underweight and normal weight groups, statistically significant differences were found in the thickness measurements at the nasion and gnathion (p < 0.05). The differences in thickness measurements at the glabella, labiale superius, stomion, labiale inferius, pogonion, gnathion, and menton are statistically significant between the underweight and overweight groups (p < 0.005). Comparing the normal and overweight groups revealed statistically significant differences the thickness measurements at the glabella, labiale superius, stomion, pogonion and menton (p < 0.05).

Characteristics of Body Composition Estimated by Air-Displacement Plethysmography in Chinese Preschool Children

Objective

To describe the characteristics of body composition by air-displacement plethysmography (ADP) among Chinese preschool children.

Methods

Preschool children were recruited from three kindergartens. Adiposity indices were evaluated using the ADP method. BMI, fat mass index (FMI), fat-free mass index (FFMI) and waist-to-height ratio (WHtR) were calculated. Overweight and obesity were diagnosed using the WHO reference. Analyses were executed by SPSS and MedCalc software. Smoothed curves were constructed using the lambda-mu-sigma (LMS) method.

Results

This study evaluated the growth trend for body composition of ADP-based body fat indices based on a relatively large sample of preschool children, the first ever reported in China. A total of 1,011 children aged 3–5 years comprised our study population. BMI and FFMI increased with age, but the slope (P = 0.710) and y intercept (P = 0.132) in the BMI trend analysis demonstrated no differences between boys and girls. For the FFMI trend lines, the slope was significantly higher for boys than for girls (P = 0.013). The percentage of fat mass (FM%), FMI, and WHtR were negatively correlated with age for both sexes, except for FMI in girls (P = 0.094). The 95% CI regression lines for FM% according to different weight statuses intersected.

Conclusions

ADP is applicable to estimating body composition among Chinese preschool children. Misclassifications might occur when overweight/obese status is defined based on surrogate indices.

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

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.

Body composition and bone mineral density by Dual Energy X-ray Absorptiometry: Reference values for young children

BACKGROUND & AIMS

Childhood obesity is a global public health threat, with an alarming rise in incidence. Obesity at young age has short-term and long-term morbidity. It is, therefore, important to accurately assess body composition throughout infancy and childhood to identify excess adiposity. However, reference values for age 2-5 years, needed to interpret measurements and identify young children at risk, are lacking. Our primary objective was to fill the current gap in reference values by constructing sex-specific body composition reference values and charts for fat mass (FM), fat mass percentage (FM%), fat mass index (FMI), lean body mass (LBM), lean body mass index (LBMI) and total body less head bone mineral density (BMD_TBLH) for children aged 2-5 years using Dual-Energy X-ray Absorptiometry (DXA).

METHODS

We performed 599 accurate DXA-measurements in 340 term-born children aged 2-5 years, using Lunar Prodigy with Encore software (V14.1). Using GAMLSS, sex-specific reference values and charts were created for FM, FM%, FMI, LBM, LBMI and BMD_TBLH.

RESULTS

Sex-specific body composition reference values and charts for age 2-5 years were constructed. In boys and girls, FM and LBM increased from age 2-5 years (all p ≤ 0.001), but body size-corrected FM% and FMI decreased (all p ≤ 0.023). LBMI remained similar between 2 and 5 years of age. Girls had higher FM, FM% and FMI and lower LBM and LBMI compared to boys. BMC and BMD_TBLH increased with age between 2 and 5 years of age (all p < 0.001) and were similar for boys and girls.

CONCLUSIONS

We present sex-specific reference values and charts for body composition and total body bone mineral density measured by DXA, based on a large cohort of healthy children aged 2-5 years. These longitudinal references can be used for clinical practice and research purposes to monitor body composition and bone mineral density development and identify children at risk for excess adiposity.

Roles of age, sex, and weight status in the muscular fitness of Chinese Tibetan children and adolescents living at altitudes over 3600 m: A cross-sectional study

OBJECTIVE

This study aimed to assess the role of age, sex, and weight status in the development of muscular fitness in a large sample of Chinese Tibetan children and adolescents aged 7-18 years living in areas over 3600 m.

METHOD

A sample of 4673 Chinese Tibetan children and adolescents aged 7-18 years were recruited from 21 schools in three cities (Lhasa, Naqu, and Anduo) of Tibet, China. Grip strength, standing long jump, 30-s sit-ups, and 50-m dash were conducted to determine muscular fitness. Independent sample t tests were conducted to compare muscular fitness between boys and girls for each age group. The changes in mean scores on each muscular fitness test were estimated. The influence of weight status on muscular strength level was also estimated using one-way ANOVA and LSD tests. We also compared the average muscular fitness between Chinese Tibetan and Chinese average level.

RESULTS

The muscular fitness of Chinese Tibetan boys aged 7-18 years was higher than that of girls, with older children outperforming younger children. Among the Chinese Tibetan boys, those in the normal-weight group showed the best performance, whereas overweight group showed the best performance among the girls. The performance of Chinese Tibetan children and adolescents in standing long jump and 50-m dash was lower while that in sit-ups was higher than the performance of their Chinese counterparts.

CONCLUSION

Chinese Tibetan children and adolescents have relatively strong abdominal strength, but lower limb strength, which needs to be improved. Age, sex, and weight status should be considered when designing interventions to improve muscular fitness.

Relationship between body mass index and physical fitness in Italian prepubertal schoolchildren

The objective of this study was to investigate the association between physical fitness and body mass index categories (obesity, OB; overweight, OW; normal-weight, NW; and underweight, UW) in prepubertal children. Anthropometric and physical fitness characteristics were collected from a convenience sample of 30472 Italian schoolchildren (6–11 years old). Six field-based tests were used: Léger, agility shuttle, long jump, frontal throw of the basketball, Sit & Reach and standing balance. Significant differences were found in the anthropometric characteristics, physical fitness and weight status prevalence between girls and boys (p<0.05) and, except for flexibility, by age class (p<0.05). Obese children performed worse than their NW counterparts in aerobic capacity (p<0.001), agility (p<0.001), muscular power of the lower limb (p<0.001) and balance (p<0.001). Conversely, children with obesity showed greater upper limb power than NW children (p<0.001). The discrepancy in physical fitness between OB and NW children increased in older girls (flexibility, p = 0.002; muscular power of the lower and upper limb, p = 0.002 and p = 0.005) and boys (aerobic capacity, p = 0.009; agility, p = 0.006; standing balance, p = 0.019; muscular power of the lower and upper limb, p<0.001 and p = 0.011) compared to their younger counterparts. On the other hand, UW children performed worse than NW children mainly in terms of muscular power of the arms (p<0.001). Additionally, there was an increasing disparity in the frontal throw test scores of UW and NW girls (p = 0.003) and boys (p = 0.011) in older children compared to younger children. In conclusion, the effect of body mass index on children’s physical fitness intensifies with age. OB and OW negatively affect aerobic capacity, agility, lower limb power and balance but positively affect upper limb power. UW negatively affects upper limb power. This study underscores the importance of preventing childhood OW, OB, and UW in early life to promote children’s health and proper fitness development.

Ethnicity Strongly Influences Body Fat Distribution Determining Serum Adipokine Profile and Metabolic Derangement in Childhood Obesity

Background: Body fat content and distribution in childhood is influenced by sex and puberty, but interethnic differences in the percentage and distribution of body fat also exist. The abdominal visceral/subcutaneous fat ratio has been the main feature of body fat distribution found to associate with the serum adipokine profile and metabolic derangement in adulthood obesity. This has also been assumed for childhood obesity despite the known singularities of this disease in the pediatric age in comparison to adults. Objective: We aimed to investigate the effect of ethnicity, together with sex and pubertal status, on body fat content and distribution, serum adipokine profile, metabolic impairment and liver steatosis in children and adolescents with obesity. Patients and Methods: One hundred and fifty children with obesity (50% Caucasians/50% Latinos; 50% males/50% females) were studied. Body fat content and distribution were studied by whole body DXA-scan and abdominal magnetic resonance, and their relationships with liver steatosis (as determined by ultrasonography), glycemia, insulinemia, lipid metabolism, uric acid, total and HMW-adiponectin, leptin, leptin-receptor, and sex steroid levels were explored. Results: Latino patients had more severe truncal obesity (higher trunk/lower limb fat ratio, odds ratio 10.00; p < 0.05) and higher prevalence of liver steatosis than Caucasians regardless of sex or pubertal status, but there were no difference in the visceral/subcutaneous abdominal fat ratio, except for pubertal females. A higher trunk/lower limb fat ratio, but not the visceral/subcutaneous abdominal fat ratio, was associated with adipokine profile impairment (higher free leptin index and lower adiponectin levels), insulin resistance and dyslipidemia, and was further enhanced when liver steatosis was present (p < 0.05). A higher abdominal visceral/subcutaneous fat ratio was observed in prepubertal children (p < 0.01), except for Latino females, whereas predominant subcutaneous fat deposition was observed in adolescents. Conclusion: Ethnicity is one of the main determinants of increased trunk body fat accumulation in Latino children with obesity, which is best estimated by the trunk/lower limb fat ratio and related to the development of metabolic derangement and liver steatosis.

Physical fitness reference standards for preschool children: The PREFIT project

OBJECTIVES

Reference values are necessary for classifying children, for health screening, and for early prevention as many non-communicable diseases aggravate during growth and development. While physical fitness reference standards are available in children aged 6 and older, such information is lacking in preschool children. Therefore, the purposes of this study were (1) to provide sex-and age-specific physical fitness reference standards for Spanish preschool children; and (2) to study sex differences across this age period and to characterise fitness performance throughout the preschool period.

DESIGN

Cross-sectional.

METHODS

A total of 3179 preschool children (1678 boys) aged 2.8-6.4 years old from Spain were included in the present study. Physical fitness was measured using the PREFIT battery.

RESULTS

Age- and sex-specific percentiles for the physical fitness components are provided. Boys performed better than girls in the cardiorespiratory fitness, muscular strength, and speed-agility tests over the whole preschool period studied and for the different percentiles. In contrast, girls performed slightly better than boys in the balance test. Older children had better performance in all fitness tests than their younger counterparts.

CONCLUSIONS

Our study provides age- and sex-specific physical fitness reference standards in preschool children allowing interpretation of fitness assessment. Sexual dimorphism in fitness tests exists already at preschool age, and these differences become larger with age. These findings will help health, sport, and school professionals to identify preschool children with a high/very low fitness level, to examine changes in fitness over time, and to analyse those changes obtained due to intervention effects.