Gender differences in total and regional body composition changes as measured by dual-energy x-ray absorptiometry in Korean children and adolescents

Change of obesity prevalence and lifestyle patterns before and during COVID-19 among Korean adolescents

PURPOSE

Lockdown measure for limiting coronavirus disease 2019 (COVID-19) spread cause an aggravation of the childhood obesity epidemic through lifestyle changes. The aim is to investigate how social restriction might have changed obesity prevalence and lifestyle patterns in Korean adolescents. We also evaluate the most fragile group and most influencing lifestyle parameters on obesity prevalence.

METHODS

To assess the change in weight status and lifestyle, we compared the Korea Youth Risk Behavior Web-based Survey data 2019 (pre-COVID-19, n=57,303) and 2020 (post-COVID-19, n=54,948). Participants from middle schools and high schools, aged 12 to 18 years, voluntarily reported their weight status and lifestyles.

RESULTS

The prevalence of obesity of the total subjects was 11.0% in 2019 and 12.1% in 2020. This prevalence difference varied by sex (males 1.8%, females 0.3%, p<0.001), age group (12-15 year 1.6%, 16-18 year 0.4%, p<0.001), and socioeconomic status. Male aged 12-15 years showed highest increase from 12.5% to 15.2%. Physical activities, fruit intake, consumption of sugar-sweetened beverages, and stress showed all decrease. Only, nonstudy sedentary time marked increased from 3.3±2.3 hr/day to 4.3±2.8 hr/day. Both moderate-intensity and vigorous-intensity physical activity marked decreased especially in male aged 12-15 years, while increased in female aged 16-18 years.

CONCLUSION

Korean adolescents showed increasing obesity prevalence after COVID-19 lockdown, with males aged 12-15 years mainly affected, mainly due to a reduced physical activity and increased sedentary time.

A growth area: A review of the value of clinical studies of child growth for palaeopathology

Studies of living children demonstrate that early life stress impacts linear growth outcomes. Stresses affecting linear growth may also impact later life health outcomes, including increased cardiometabolic disease risk. Palaeopathologists also assess the growth of children recovered from bioarchaeological contexts. Early life stresses are inferred to affect linear growth outcomes, and measurements of skeletal linear dimensions alongside other bioarchaeological information may indicate the types of challenges faced by past groups. In clinical settings, the impacts of stress on growing children are typically measured by examining height. Palaeopathologists are limited to examining bone dimensions directly and must grapple with incomplete pictures of childhood experiences that may affect growth. Palaeopathologists may use clinical growth studies to inform observations among past children; however, there may be issues with this approach. Here, we review the relationship between contemporary and palaeopathological studies of child and adolescent growth. We identify approaches to help bridge the gap between palaeopathological and biomedical growth studies. We advocate for: the creation of bone-specific growth reference information using medical imaging and greater examination of limb proportions; the inclusion of children from different global regions and life circumstances in contemporary bone growth studies; and greater collaboration and dialogue between palaeopathologists and clinicians as new studies are designed to assess linear growth past and present. We advocate for building stronger bridges between these fields to improve interpretations of growth patterns across human history and to potentially improve interventions for children living and growing today.

Studies of living children demonstrate that early life stress impacts linear growth. Stresses affecting linear growth may also impact later life health, including cardiometabolic disease risk. Palaeopathologists also investigate if children and adolescents recovered from bioarchaeological contexts experienced growth disruptions due to early life challenges. In clinical settings, the impacts of stress on growing children are typically measured by examining height. Palaeopathologists are limited to examining bone dimensions directly and must grapple with incomplete pictures of childhood experiences that may affect growth. Here, we review the relationship between contemporary and palaeopathological studies of child and adolescent growth. We advocate for: the creation of bone-specific growth reference information using medical imaging and greater examination of limb proportions; the inclusion of children from different global regions and life circumstances in contemporary bone growth studies; and greater collaboration and dialogue between palaeopathologists and clinicians as new studies are designed to assess linear growth past and present. These steps may improve interpretations of growth patterns across human history and interventions for children living and growing today.

Total, bioavailable and free 25-hydroxyvitamin D levels as functional indicators for bone parameters in healthy children

Objectives

Vitamin D is essential for bone health. Not only total but also free 25-hydroxyvitamin D (25OHD) may contribute to bone mass. We sought to determine which vitamin D measure best reflected clinical and bone parameters in healthy children.

Methods

A cross-sectional study including 146 healthy children (71 boys, 9.5 ± 1.9 years) conducted at a tertiary medical center. We used a multiplex liquid chromatography-tandem mass spectrometry-based assay to simultaneously measure vitamin D metabolites. The bioavailable and free 25OHD (25OHD_BioA and 25OHD_Free) levels were calculated using the genotype-specific or genotype-constant affinity coefficients of vitamin D-binding proteins (yielding spe-25OHD_BioA, spe-25OHD_Free and con-25OHD_BioA, con-25OHD_Free respectively). The 25OHD_Free level was directly measured (m-25OHD_Free). Bone mineral content (BMC) and bone mineral density (BMD) were assessed via dual-energy X-ray absorptiometry.

Results

The total 25OHD (25OHD_Total), the two forms of 25OHD_BioA, the three forms of 25OHD_Free, and 24,25-dihydroxyvitamin D₃ levels correlated with parathyroid hormone level (all p < 0.01). Serum 25OHD_Total and m-25OHD_Free levels were influenced by age, pubertal status, season, body mass index (BMI), daylight hours, and vitamin D intake (all p < 0.05). The con-25OHD_BioA and con-25OHD_Free levels better reflected pubertal status and daylight hours than did the spe-25OHD_BioA and spe-25OHD_Free levels (both p < 0.01). The association between the 25OHD_Total level and bone parameters varied according to the BMI (interaction p < 0.05). In 109 normal-weight children, the con-25OHD_BioA and con-25OHD_Free levels correlated with total body BMC and BMD (both p < 0.05), whereas the 25OHD_Total and 24,25-dihydroxyvitamin D₃ levels were associated with total body BMC (both p < 0.05). No such association was found in overweight or obese children.

Conclusions

In healthy children, total, bioavailable, and free 25OHD levels comparably reflected lifestyle factors. In normal-weight children, the con-25OHD_BioA and con-25OHD_Free, but not m-25OHD_Free levels, reflected bone mass, as did the 25OHD_Total level.

Maternal Hyperglycemia during Pregnancy Increases Adiposity of Offspring

BACKGROUND

The effect of intrauterine hyperglycemia on fat mass and regional fat proportion of the offspring of mothers with gestational diabetes mellitus (OGDM) remains to be determined.

METHODS

The body composition of OGDM (n=25) and offspring of normoglycemic mothers (n=49) was compared using dualenergy X-ray absorptiometry at age 5 years. The relationship between maternal glucose concentration during a 100 g oral glucose tolerance test (OGTT) and regional fat mass or proportion was analyzed after adjusting for maternal prepregnancy body mass index (BMI).

RESULTS

BMI was comparable between OGDM and control (median, 16.0 kg/m2 vs. 16.1 kg/m2 ). Total, truncal, and leg fat mass were higher in OGDM compared with control (3,769 g vs. 2,245 g, P=0.004; 1,289 g vs. 870 g, P=0.017; 1,638 g vs. 961 g, P=0.002, respectively), whereas total lean mass was lower in OGDM (15,688 g vs. 16,941 g, P=0.001). Among OGDM, total and truncal fat mass were correlated with fasting and 3-hour glucose concentrations of maternal 100 g OGTT during pregnancy (total fat mass, r=0.49, P=0.018 [fasting], r=0.473, P=0.023 [3-hour]; truncal fat mass, r=0.571, P=0.004 [fasting], r=0.558, P=0.006 [3-hour]), but there was no correlation between OGDM leg fat mass and maternal OGTT during pregnancy. Regional fat indices were not correlated with concurrent maternal 75 g OGTT values.

CONCLUSION

Intrauterine hyperglycemia is associated with increased fat mass, especially truncal fat, in OGDM aged 5 years.

Overview of pediatric obesity: diagnosis, epidemiology, and significance

Background: The prevalence of pediatric obesity has increased over the past several decades worldwide and in Korea. Childhood obesity has become a serious social problem.Current Concepts: Diagnosis of obesity is based on body mass index (BMI) in children and adolescents aged ≥2 years. Overweight and obese are defined as BMI ≥85th percentile to <95th percentile and BMI ≥95th percentile, respectively, corresponding to sex and age. Obesity is further classified as Class I (BMI ≥95th percentile to <120% of 95th percentile), Class II (BMI ≥120% of 95th percentile to <140% of 95th percentile), and Class III (BMI ≥140% of 95th percentile). Waist circumference and waist-height ratio are used to evaluate abdominal obesity. Pediatric obesity can cause childhood comorbidities, including type 2 diabetes, dyslipidemia, non-alcoholic fatty liver disease, and hypertension. Adult obesity, cardiovascular diseases, and other adult comorbidities, together with increased medical costs are additional consequences of pediatric obesity.Discussion and Conclusion: Prevention, diagnosis, and proper management of pediatric obesity are important.

Evenly Distributed Protein Intake over 3 Meals Augments Resistance Exercise-Induced Muscle Hypertrophy in Healthy Young Men

BACKGROUND

Although daily protein intake (PI) has been reported to be essential for regulating muscle mass, the distribution of daily PI in individuals is typically the lowest at breakfast and skewed toward dinner. Skewed protein intake patterns and inadequate PI at breakfast were reported to be negative factors for muscle maintenance.

OBJECTIVES

This study examined whether a protein-enriched meal at breakfast is more effective for muscle accretion compared with the typical skewed PI pattern.

METHODS

This 12-wk, parallel-group, randomized clinical trial included 26 men (means ± SEs; age: 20.8 ± 0.4 y; BMI: 21.8 ± 0.4 kg/m2). The "high breakfast" (HBR) group (n = 12) consumed a protein-enriched meal at breakfast providing a PI of 0.33 g/kg body weight (BW); their PI at lunch (0.46 g/kg BW) and dinner (0.48 g/kg BW) provided an adequate overall daily PI (1.30 g/kg BW/d). The "low breakfast" (LBR) group (n = 14) consumed 0.12 g protein/kg BW at breakfast; intakes at lunch (0.45 g/kg BW) and dinner (0.83 g/kg BW) yielded the same daily PI as in the HBR group. The participants performed supervised resistance training (RT) 3 times per week (75-80% 1-repetition maximum; 3 sets × 10 repetitions). DXA was used to measure the primary outcome variable, that is, total lean soft tissue mass (LTM).

RESULTS

The total LTM at baseline did not differ between the HBR (52.4 ± 1.3 kg) and LBR (53.4 ± 1.2 kg) groups. After the intervention, increases in total LTM were significant in both groups, with that in the HBR group (2.5 ± 0.3 kg) tending to be greater than that in the LBR group (1.8 ± 0.3 kg) (P = 0.06), with a large effect size (Cohen d = 0.795).

CONCLUSIONS

For RT-induced muscle hypertrophy in healthy young men, consuming a protein-enriched meal at breakfast and less protein at dinner while achieving an adequate overall PI is more effective than consuming more protein at dinner.This study was registered at University hospital Medical Information Network (UMIN) Clinical Trials Registry as UMIN000037583 (https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000042763).

Body composition and bone density reference data for Korean children, adolescents, and young adults according to age and sex: results of the 2009-2010 Korean National Health and Nutrition Examination Survey (KNHANES)

We established the timing of peak bone mass acquisition and body composition maturation and provide an age- and sex-specific body composition and bone density reference database using dual-energy X-ray absorptiometry in Korean subjects 10-25 years of age. Reference percentiles and curves were developed for bone mineral content (BMC), bone mineral density (BMD) of the whole body, the lumbar spine, and the femoral neck, and for fat mass (FM) and lean mass (LM) of 1969 healthy participants (982 males) who participated in the 2009-2010 Korean National Health and Nutrition Examination Survey. Additionally, bone mineral apparent density (BMAD), FM index, and LM index were calculated to adjust for body size. BMC and BMD at all skeletal sites as well as LM increased with age, reaching plateaus at 17-20 years of age in females and 20-23 years of age in males. The femoral neck was the first to reach a bone mass plateau, followed by the lumbar spine and then the whole body. Spine BMAD increased with age in both sexes, but femoral and whole-body BMAD remained the same over time. Females displayed a dramatic increase in FM during puberty, but the FM of males decreased until mid-puberty. These findings indicate that bone health and body composition should be monitored using a normal reference database until the late second to early third decade of life, when statural growth and somatic maturation are completed.

Body composition assessment using DXA in six-year-old children: the 2004 Pelotas Birth Cohort, Rio Grande do Sul State, Brazil

The aim of this study was to describe fat (FM) and lean body mass (LBM) in six-year-old children from the 2004 Pelotas Birth Cohort, stratified by gender. Dual-Energy X-ray Absorptiometry was used to measure FM and LBM, FM and LBM indexes, and percentage (%) of FM and LBM. Mean measures of adiposity were higher among girls (6.3kg, 4.2kg/m2 and 23.4% vs. 5kg, 3.3kg/m2 and 18%) while LBM measures were higher among boys (19.3kg, 13kg/m2 and 78.5% vs. 17.7kg, 12.2kg/m2 and 73.2%). In both boys and girls mean measures of adiposity increased with socioeconomic status and maternal education. Mean measures of adiposity were higher among white-skinned children while %LBM was higher among black-skinned children. Preterm compared to full-term children showed lower mean measures of adiposity and LBM. Female sex, white skin color and higher socioeconomic conditions are associated with higher adiposity in childhood.

Prevalence of insulin resistance and cardiometabolic risk in Korean children and adolescents: a population-based study

AIMS

We aimed to establish normal reference values of serum insulin and the homeostasis model assessment of insulin resistance (HOMA-IR). We also aimed to verify HOMA-IR "cut-off values" in predicting cardiometabolic risk among Korean children and adolescents.

METHODS

Data from 2716 Korean subjects (1421 male and 1295 female, aged 10-20 years) were evaluated. Insulin resistance was defined as HOMA-IR >95th percentile. The odds ratios of cardiometabolic risk were assessed based on the state of insulin resistance.

RESULTS

Reference values of insulin and HOMA-IR were determined according to sex and age, based on data obtained from normal-weight subjects with normal fasting glucose levels. HOMA-IR values appeared to peak at the age of 14-15 years in male subjects and at the age of 12-13 years in female subjects. The prevalence of insulin resistance in the subjects was 9.8% (male=10.9%, female=8.6%). The prevalence of insulin resistance in normal-weight, overweight, and obese subjects were 4.7%, 25.6%, and 47.1% respectively. Subjects with insulin resistance had a higher prevalence of metabolic syndrome (odds ratios=18.33; 95% confidence interval, 9.62-34.94) and its components, especially hyperglycemia and hypertriglyceridemia.

CONCLUSION

We established reference values of serum insulin and HOMA-IR according to age and sex. Obesity is the most important risk factor for insulin resistance and metabolic syndrome. However, insulin resistance independently increases cardiometabolic risk. This information may be useful for Korean as well as other Asian in planning programs for the prevention of type 2 diabetes.

Changes in bone mineral density and body composition of children with well-controlled homocystinuria caused by CBS deficiency

Homocystinuria due to cystathionine β-synthase (CBS) deficiency is an inherited disorder of the metabolism of methionine. Clinical manifestations include mental retardation, dislocation of the optic lens, vascular lesions, arterial and venous thromboembolism, skeletal abnormalities, and osteoporosis. Most homocystinuria patients diagnosed in adulthood have severe osteoporosis, and homocystinuria is frequently mentioned as a cause of osteoporosis. Good control of plasma homocysteine may prevent or delay some of these complications. However, the effectiveness of bone mineral density (BMD) gain or fracture prevention has not been addressed. Here, we describe changes in BMD and body composition in 5 CBS deficiency patients who were diagnosed at young age and were managed with good metabolic control. We found that the BMD of each region was within the normal range. BMD gain was adequate and the patients had no significant change in skeletal morphology.

Adequate vitamin D status and adiposity contribute to bone health in peripubertal nonobese children

The dietary reference intake (DRI) of vitamin D for Korean children was reduced from 400 IU/day in 2005 to 200 IU/day in 2010. We evaluated the risk factors for low 25-hydroxyvitamin D [25(OH)D] status and its relationships with bone health in peripubertal nonobese children living in Seoul or Gyeonggi-do. One hundred children (9.3 ± 1.9 years, 71 prepubertal, 45 boys) participated in the winter (n = 38, December through March) and summer (June through September). Bone mineral content (Z_BMC), fat mass (Z_FM), lean mass (Z_LM), and bone mineral density for the total body (Z_TB) and lumbar spine (Z_L1-4) were measured using dual-energy X-ray absorptiometry. Twenty-nine percent of children (47.4 % in winter, 17.7 % in summer) were vitamin D deficient (25(OH)D level of <20 ng/mL). The winter season (P = 0.008) and low vitamin D intake (P = 0.044) were associated with low 25(OH)D level. The 25(OH)D level correlated positively with Z_BMC (P = 0.040), Z_TB (P = 0.027), and Z_L1-4 (P = 0.045) independently of sex, puberty, Z_FM, Z_LM, physical activity level, and calcium intake. Z_FM correlated independently with Z_BMC (P < 0.001), Z_TB (P = 0.037), and Z_L1-4 (P < 0.001). In conclusion, almost half of peripubertal nonobese children were vitamin D deficient in winter. Adequate vitamin D status and adiposity contributed to good bone health in nonobese children. Considering the beneficial effects of adequate vitamin D status on bone health, the current DRI may be insufficient for preventing vitamin D deficiency in winter among Korean children.

Young age at diagnosis, male sex, and decreased lean mass are risk factors of osteoporosis in long-term survivors of osteosarcoma

BACKGROUND

Long-term survival of children with osteosarcoma has increased, but most suffer from osteoporosis in adulthood. The aim of this study was to investigate the prevalence and identify the risk factors of osteoporosis.

METHODS

Forty long-term survivors of osteosarcoma and 55 controls were enrolled. The mean age of the survivors was 21.8 ± 5.2 years. They were diagnosed at younger than 23 years of age (mean, 14.9 + 5.0 y). Bone mineral densities (BMD) and body compositions were measured by dual-energy x-ray absorptiometry.

RESULTS

Nineteen (47.5%) subjects had osteoporosis and 12 (30.0%) had osteopenia. The regions affected by osteoporosis were: femur neck of osteosarcoma site (47.5%), unaffected femur neck (12.5%), lumbar spine (12.5%), and total body (15.0%). Twelve subjects (30.0%) had 14 episodes of fractures. The identified risk factors of osteoporosis were young age at diagnosis, male sex, and low lean mass. Subjects diagnosed before attainment of puberty (male ≤ 16 y, female ≤ 14 y) were found to have a higher prevalence of osteoporosis (37.5% vs. 10.0%, P < 0.01). Males had a higher prevalence of osteopenia or osteoporosis than females (86.4% vs. 66.7%, P < 0.01). Total lean mass was positively correlated with unaffected femur neck BMD. Regional lean mass in affected limb was significantly reduced along with affected femur neck BMD.

CONCLUSIONS

In long-term survivors of osteosarcoma, prevalence of osteoporosis and fracture was higher than expected. Initial evaluation and regular follow-up of BMD should be performed in all osteosarcoma patients, especially in those who did not attain puberty, males, and those with a low lean mass.

The effect of gonadotrophin-releasing hormone agonist treatment over 3 years on bone mineral density and body composition in girls with central precocious puberty

OBJECTIVE

Puberty is a period characterized by growth spurt and rapid change in body composition. The effect of GnRH agonist therapy for central precocious puberty on bone mineral density is unclear. We demonstrated changes in bone mineral density in subjects with central precocious puberty, who were treated with GnRH agonist for more than 3 years.

DESIGN

The changes in bone mineral density and body compositions were tested with analysis of variance with repeated measures to identify statistical significance over the treatment period.

PATIENTS

One hundred ninety-five Korean girls with central precocious puberty were treated with GnRH agonist, and among these subjects, 39 patients were treated for more than 3 years.

MEASUREMENTS

Dual-energy X-ray absorptiometry was performed on the subjects at the initial evaluation and once yearly thereafter while on the treatment.

RESULTS

The bone mineral density parameters for chronological age tended to decrease near the mean for the treatment period; however, they increased significantly for bone age excluding bone mineral apparent density. An increment of the BMI was not significant for the chronological age.

CONCLUSIONS

Three-year treatment with GnRH agonist in central precocious puberty patients did not impair bone maturation. GnRH agonist could be effectively commenced in girls with precocious puberty from an early age.

Risk factors for osteoporosis in long-term survivors of intracranial germ cell tumors

SUMMARY

We measured bone mineral densities in 28 intracranial germ cell tumor long-term survivors. There was the high prevalence of osteoporosis and osteopenia, 25.0% and 42.9%, respectively, and three additional risk factors, male sex, a low lean mass, and adult growth hormone replacement, were identified.

INTRODUCTION

Intracranial germ cell tumor long-term survivors (iGCTLS) have many risk factors for osteoporosis, including irradiation from cancer therapy and multiple hormone deficiencies. However, no study of bone mineral density (BMD) has been conducted in iGCTLS because these tumors are rare. The aims of this study were to evaluate the prevalence of osteoporosis and to identify risk factors associated with reduced bone mass in iGCTLS.

METHODS

We evaluated BMD and body composition of 28 iGCTLS (10.9 ± 5.2 years after cancer treatment; 13 males) using dual-energy X-ray absorptiometry. To determine risk factors, we analyzed the medical history, including the nature of the tumor, treatment modality, endocrine status, hormone replacement therapy, lifestyle, and biochemical parameters.

RESULTS

Twenty-five percent of iGCTLS were diagnosed with osteoporosis and 42.9% with osteopenia. Most males (92.3%) had low BMD. Lean mass (LM) was positively correlated with BMD in all regions of interest, and the starting age of adult growth hormone (GH) replacement was negatively correlated with the BMD Z-score at the femur neck. In logistic regression analysis, male sex and low LM were related to low BMD.

CONCLUSIONS

The iGCTLS had a high prevalence of low BMD. We found that male sex, low LM, and delayed start of adult GH replacement were risk factors for osteoporosis. Therefore, the BMD of all iGCTLS should be evaluated, and if it is low, proper management should be started early.