Secular Trends in Pediatric Overweight and Obesity in Korea

Secular trends in BMI, excess weight and body fat skinfolds in Peruvian children living at high altitude

BACKGROUND

There is limited evidence on secular trends in adiposity among high-altitude children.

AIMS

To describe secular trends in body mass index (BMI), excess weight and body fat skinfolds (SKF) among Peruvian children living at high altitude and to investigate the risk for excess weight in 2019 relative to 2009.

SUBJECTS AND METHODS

We sampled 1585 Peruvians aged 6-11 years from the Junín region. Height and weight were measured, and BMI was calculated. WHO cut-offs were used to classify children by weight status. The sum of SKF was used for analysis. BMI and sum SKF were log-transformed. Two-factor ANOVA and post-hoc contrasts were used together with trend plots for BMIlog and SKFlog. Relative risks for excess weight were estimated with 95% confidence intervals. All analyses were done in STATA.

RESULTS

BMIlog and SKFlog means increased in both sexes from 2009 to 2019, with age-specific variation. Between 2009 and 2019, BMI values shifted from near P50 to P75 on WHO percentiles for both sexes in most age groups. The risk of excess weight was not significantly higher for most children in 2019 compared to 2009.

CONCLUSIONS

Positive secular trends in BMIlog and SKFlog were observed, with significant increases at specific ages.

The changes in the prevalence of underweight and short stature among Polish youth from 1938 to 2020

BACKGROUND

The issues of underweight and short stature are significant yet underrepresented in the literature.

AIM

This study examines the prevalence of changes in underweight and short stature among Polish youth from 1938 to 2020.

SUBJECTS AND METHODS

Utilising five cross-sectional data sets from Kraków, Poland, the study analysed 24,655 children and adolescents aged 3-18 years. Height and weight were measured, with BMI calculated. Underweight was determined using Cole's cut-off points, while short stature was defined as height below -2 standard deviations from the mean for age and sex.

RESULTS

For girls, the prevalence of underweight remained stable at approximately 9.5% from 1938 to 2020, peaking in 1983, particularly during puberty, before declining in subsequent cohorts. In boys, underweight prevalence varied more, from 5.6% in 1938 to 11.1% in 1983, with a steady decline thereafter. Short stature prevalence for both sexes remained low (1.5-2.5%) and unchanged over 85 years.

CONCLUSION

Underweight prevalence increased significantly from 1938 to 1983, reflecting adverse environmental conditions, but has decreased in the last four decades, highlighting socioeconomic influences. Both underweight and short stature can significantly affect children's health.

ACTION Teens: Perceptions and attitudes towards obesity among adolescents living with obesity, caregivers and healthcare professionals in South Korea

BACKGROUND

In South Korea, the prevalence of adolescents living with obesity (ALwO) is rising.

OBJECTIVES

To evaluate perceptions, attitudes, behaviors, and obstacles to effective obesity care among ALwO, caregivers, and healthcare professionals (HCPs) in South Korea.

METHODS

ACTION Teens (NCT05013359) was a multinational, cross-sectional survey conducted in 2021. Data from South Korean participants are reported (476 ALwO, 523 caregivers, 200 HCPs).

RESULTS

Most ALwO/caregivers acknowledged that they/their ALwO had overweight, obesity or severe obesity (95 %/88 %, respectively) and were concerned about weight impacting their/their ALwO's future health (94 %/91 %, respectively). The predominant information source on weight management for ALwO/caregivers was YouTube (62 %/35 %, respectively). Most HCPs (87 %) indicated obesity had a strong impact on overall health; fewer ALwO (70 %) and caregivers (62 %) provided the same responses. ALwO recognized the societal challenges associated with overweight/obesity (versus healthy weight), with 50 %, 37 %, and 36 % reporting that overweight/obesity makes it harder to get a job, make friends, and perform well at school, respectively (compared with 41 %, 28 %, and 26 % of caregivers). A higher proportion of ALwO (80 %) than caregivers (45 %) thought weight loss was completely the ALwO's responsibility. While 82 % of ALwO reported they had made a recent weight-loss attempt, only 60 % of caregivers reported that their ALwO had made a recent weight-loss attempt; HCPs thought that, on average, 35 % of their ALwO patients had attempted to lose weight.

CONCLUSIONS

Disparities in respondents' perceptions and attitudes toward obesity underscore the need for enhanced communication and increased understanding of obesity to improve healthcare strategies for South Korean ALwO.

Dyslipidemia in Children and Adolescents: Current Insights and Updated Treatment Approaches

The increasing incidence of dyslipidemia among children and adolescents has emerged as a significant public health concern due to its associated risk of long-term cardiovascular complications. The prevalence of dyslipidemia has increased in parallel with rising obesity rates, highlighting the importance of early intervention. In this narrative review, we explore the epidemiology, screening, diagnosis, and treatment of dyslipidemia in pediatric populations, focusing on recent advancements and updates in clinical management. Key diagnostic criteria and risk assessment strategies are discussed, emphasizing the role of lipid profile screening in high-risk groups. Lifestyle and dietary interventions are key for managing dyslipidemia, while pharmacological treatments including statins, cholesterol absorption inhibitors, and emerging therapies are reviewed in cases requiring further intervention. Updated guidelines and evidence-based recommendations from Korean and other international institutions are consolidated to provide a comprehensive overview. These findings underscore the necessity of a multidisciplinary approach combining early detection, tailored treatment, and lifestyle modifications to mitigate the long-term health risks associated with dyslipidemia in younger individuals.

Endocrine and metabolic comorbidities in juvenile-onset systemic lupus erythematosus

Background and aims

Juvenile-onset systemic lupus erythematosus (JSLE) is a chronic autoimmune disease affecting individuals under 18, causing multi-system impairment. Patients with JSLE exhibit more severe disease when compared to patients with adult-onset SLE. This study aimed to evaluate the prevalence of endocrine and metabolic comorbidities in patients with JSLE, and analyze the factors associated with each comorbidity.

Methods

Anthropometric, clinical, laboratory data, and the details of glucocorticoids and disease-modifying anti-rheumatic drugs use were collected.

Results

A total of 57 patients with JSLE (48 girls and 9 boys) were included in this study. Endocrine and metabolic comorbidities were observed in 64.9% of the patients. The most prevalent comorbidities were dyslipidemia (40.4%), being overweight or obese (26.3%), subclinical hypothyroidism (24.6%), autoimmune thyroid disease (AITD) (21.1%), and low bone mass (20.9%). The risk of dyslipidemia and AITD increased in patients who were overweight or obese. The risk of being overweight or obese was associated with skin involvement at diagnosis and rheumatoid factor positivity. Younger age at diagnosis and longer duration of glucocorticoid exposure increased the risk of low bone mass. The overall prevalence of endocrine and metabolic comorbidities was associated with short stature at diagnosis, being overweight or obese at follow-up, skin involvement at diagnosis, and rheumatoid factor positivity.

Conclusion

Patients with JSLE have higher burdens of endocrine and metabolic comorbidities and should be routinely monitored. Prevention of obesity may be helpful in lowering the risk of comorbidities.

Prevalence of childhood overweight and obesity in Malaysia: a systematic review and meta-analysis

The incidence of childhood obesity is increasing worldwide. National surveys in Malaysia have shown similar trends. This review aimed to increase our understanding of the prevalence and associated factors of childhood overweight, obesity, and excess weight in Malaysia. A systematic review and meta-analysis were conducted of studies reporting the prevalence of overweight and obesity in Malaysian children aged <18 years. Systematic searches were conducted in October 2023 and repeated in March 2024 of the PubMed, Scopus, and Web of Science databases. The grey literature was also included. Study selection, data extraction, and quality assessments were conducted by paired independent researchers. A metaanalysis of prevalence and 95% confidence interval (CI) using a random-effects model and heterogeneity (I2) was calculated. Publication bias was investigated using Egger's test. This review included 33 studies (N=273,710) conducted between 1996 and 2022. Overall, the childhood overweight, obesity and excess weight prevalence was 13.9% (95% CI, 13.0%-14.8%), 11.8% (95% CI, 10.9%-12.8%), and 24.0% (95% CI, 22.3%-25.7%), respectively. Boys had a significantly higher proportion of obesity (12.5% [95% CI, 11.1%-14.1%] vs. 9.1% [95% CI, 8.1%-10.1%]) and excess weight (25.7% [95% CI, 23.5%-28.1%] vs. 20.7% [95% CI, 18.8%-22.8%]) than girls. Sarawak natives had a higher prevalence of obesity (17.7% [95% CI, 16.0%-19.5%]). Annually, the obesity prevalence increased by 0.3% (95% CI, 0.1%-0.6%; P=0.006) and excess weight prevalence increased by 0.6% (95% CI, 0.3%-1.0%; P=0.002). Heterogeneity was high (I2>90%), and publication bias was possible (P<0.001). Variability was not significantly affected by the critical appraisal score or sample size. In conclusion, the prevalence of childhood overweight, obesity, and excess weight in Malaysia doubled over 26 years. Future studies of the prevalence of childhood excess weight should follow a standardized reference for body mass index by age to ease interstudy comparisons.

Risk Factors Related to Resting Metabolic Rate-Related DNAJC6 Gene Variation in Children with Overweight/Obesity: 3-Year Panel Study

This study investigated how the DNACJ6 gene variation related to RMR alteration affects risk factors of obese environments in children with obesity aged 8-9.

METHODS

Over a three-year follow-up period, 63.3% of original students participated. Changes in the variables (anthropometrics, blood biochemistry, and dietary intakes) were analyzed and compared between those without obesity (non-OB) and with obesity (OB) classified at the study endpoint.

RESULT

The average MAF of nine SNPs (D-1 to D-IX) was defined as 18.1%. The OB group showed greater increases in RMR, BMI, WC, and SBP, while the non-OB group had significantly greater increases in HDL and intakes of nutrients (e.g., total calories, vitamins B2, C, folate, A, retinol, iron, and zinc). Increased RMR, BMI, BW, and RMR/BW changes were observed with mutant allele of D-I SNP, which was also associated with a higher prevalence of obesity. Greater increases in animal fat intake, including saturated fatty acids and retinol, were noted in the minor alleles of D-VI, D-VII, D-VIII, and D-IX SNPs compared to those of the major alleles. The odds ratio for BMI risk was significantly higher in the mutant alleles of D-I (rs17127601), D-VII (rs1334880), and D-VIII (rs7354899) compared to the wild type, with increases of 2.59 times (CI; 1.068-6.274), 1.86 times (CI; 1.012-3.422), and 1.85 times (CI; 1.008-3.416), respectively. RMR was a mild risk factor in minors of the D-1, D-VII, and D-VIII; however, a higher RMR/BW ratio significantly correlated with decreased BMI risk, and this effect was found in only the major alleles of D-I, D-VII, and D-VIII SNPs, not in the minor alleles. High retinol intake appeared to reduce obesity risk in the minor alleles of the D-I, D-VII, and D-VIII SNPs, even though intake of animal fats and retinol remained higher among minors over the three years.

CONCLUSIONS

These findings suggest that the RMR/BW ratio and dietary fat/retinol intake should be considered in DNACJ6-gene-based precision medicine approaches for pediatric obesity prevention, particularly for boys.

Protecting our future: environmental hazards and children's health in the face of environmental threats: a comprehensive overview

Children face the excitement of a changing world but also encounter environmental threats to their health that were neither known nor suspected several decades ago. Children are at particular risk of exposure to pollutants that are widely dispersed in the air, water, and food. Children and adolescents are exposed to chemical, physical, and biological risks at home, in school, and elsewhere. Actions are needed to reduce these risks for children exposed to a series of environmental hazards. Exposure to a number of persistent environmental pollutants including air pollutants, endocrine disruptors, noise, electromagnetic waves (EMWs), tobacco and other noxious substances, heavy metals, and microplastics, is linked to damage to the nervous and immune systems and affects reproductive function and development. Exposure to environmental hazards is responsible for several acute and chronic diseases that have replaced infectious diseases as the principal cause of illnesses and death during childhood. Children are disproportionately exposed to environmental toxicities. Children drink more water, eat more food, and breathe more frequently than adults. As a result, children have a substantially heavier exposure to toxins present in water, food, or air than adults. In addition, their hand-to-mouth behaviors and the fact that they live and play close to the ground make them more vulnerable than adults. Children undergo rapid growth and development processes that are easily disrupted. These systems are very delicate and cannot adequately repair thetional development in children's environmental health was the Declaration of the Environment Leaders of the Eight on Children's Environmental Health by the Group of Eight. In 2002, the World Health Organization launched an initiative to improve children's environmental protection effort. Here, we review major environmental pollutants and related hazards among children and adolescents.

Big data-based reference centiles for body composition in Korean children and adolescents: a cross-sectional study

BACKGROUND

The changes in body composition during puberty not only contribute to the differences in body composition between adult males and females but also have associations with growth problems and metabolic disorders, including obesity. Therefore, understanding the changes in body composition during the pubertal period and analyzing reference values based on race and gender are essential research resources. The objective of this study was to generate reference centiles for body composition on a monthly basis using an extensive dataset of body composition information from Korean children and adolescents.

METHODS

A total of 88,069 measurements from 22,515 children (11,062 boys and 11,453 girls) aged 7-16 years using a bioelectrical impedance analysis were included in the study after performing a Z-score-based data management procedure. Height, weight, body fat mass (BFM), and fat-free mass (FFM) were measured and used to derive body fat percentage (BF%), body mass index (BMI), fat mass index (FMI), and fat-free mass index (FFMI). Sex- and age-specific centiles were estimated using generalized additive models for location, scale, and shape with the Box-Cox Cole and Green distribution (i.e., lambda-mu-sigma method).

RESULTS

The sex- and age-related disparities in body composition were most pronounced when weight was partitioned into BFM and FFM. In boys, the FFM increased markedly during pubertal growth spurts, whereas BFM remained relatively stable. In girls, the BFM increased steadily, whereas the rate of FFM increased slowly. The BMI increased steadily with age in both sexes. However, when BMI was parsed into FMI and FFMI, it became clear that the FFMI increased substantially during pubertal growth in boys, whereas the FMI peaked around age 11 and then declined. Conversely, the FMI increased steadily in girls, albeit with a slowing rate in the increase of the FFMI beginning around age 12.

CONCLUSIONS

This study produced age- and sex-specific reference percentiles for body composition indices in Korean children and adolescents using extensive biometric data.

Barriers and Facilitators of Pediatric Obesity Prevention and Management (POPM) Programs in Korea: Focusing on the Questionnaire About the Linkage in Community Level

BACKGROUND

Recent global trends indicate a rise in pediatric obesity, reflecting patterns also observed in South Korea. Given its significant impact on chronic disease prevalence in adulthood, pediatric obesity poses potential societal challenges. For pediatric obesity-related prevention or management programs in community level to operate effectively, there needs to be a clear understanding of barriers and facilitators of the programs. This study aims to establish a foundation for policy implementation, contributing to pediatric obesity prevention and management (POPM) in Korea.

METHODS

A survey was conducted among program providers involved in domestic POPM programs. A total of 577 individuals completed the survey, including those working in elementary and middle schools (n = 508) and public health centers (n = 69) nationwide. The questionnaire comprised 67 questions covering characteristics of respondents, purpose and contents of POPM programs, measurement of program outcome, level of inter- and intra-institutional linkage, difficulties in operating programs and factors that facilitate programs. A 5-point Likert scale was used for most questions. Descriptive statistics was employed to analyze characteristics of respondents in POPM programs. The level of linkage in POPM programs was assessed using perceived importance and actual degree of linkage. The difficulties in operating POPM programs were analyzed based on agreement responses, and facilitating factors of program activation were analyzed based on importance responses.

RESULTS

The domestic POPM program showed low actual linkage compared to its perceived importance, both between institutions and among professions within institutions. Difficulties in operating the program included securing availability of students, encouraging participation of reluctant students and development of new programs. The survey suggested that schools require support from parents, guardians and family members, while public health centers need professional providers to facilitate such programs.

CONCLUSION

The study highlights the urgent need for strategies to address pediatric obesity in South Korea. Weak institutional linkages hinder effective programs. Challenges include student availability, participation, and the need for innovative programs. New approaches to build partnerships in harmony among institutions are necessary. Implementing findings into policy can help prevent obesity in Korean children and adolescents.

Obesity and hypertension in children and adolescents

As childhood obesity rates increase worldwide, the prevalence of obesity-related hypertension is also on the rise. Obesity has been identified as a significant risk factor for hypertension in this age group. National Health Surveys and meta-analyses show increasing trends in obesity and pediatric hypertension in obese children. The diagnosis of hypertension in children involves percentiles relative to age, sex, and height, unlike in adults, where absolute values are considered. Elevated blood pressure (BP) in childhood is consistently associated with cardiovascular disease in adulthood, emphasizing the need for early detection and intervention. The pathogenesis of hypertension in obesity involves multiple factors, including increased sympathetic nervous system activity, activation of the renin-angiotensin-aldosterone system (RAAS), and renal compression due to fat accumulation. Obesity disrupts normal RAAS suppression and contributes to impaired pressure natriuresis and sodium retention, which are critical factors in the development of hypertension. Risk factors for hypertension in obesity include degree, duration, and distribution of obesity, patient age, hormonal changes during puberty, high-sodium diet, sedentary lifestyle, and socioeconomic status. Treatment involves lifestyle changes, with weight loss being crucial to lowering BP. Medications such as angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers may be considered first, and surgical approaches may be an option for severe obesity, requiring tailored antihypertensive medications that consider individual pathophysiology to avoid exacerbating insulin resistance and dyslipidemia.

Association between metabolically healthy obesity and carotid intima-media thickness in Korean adolescents with overweight and obesity

PURPOSE

Data regarding the association between metabolically healthy obesity (MHO) and preclinical atherosclerosis in childhood are lacking. Carotid intima-media thickness (cIMT) is a noninvasive method used to assess cardiovascular risk. This study examined the relationships among cIMT, metabolic phenotypes, and cardiometabolic risk factors (CMRFs) in overweight and obese adolescents.

METHODS

Anthropometric, biochemical, and cIMT data were collected. The study participants were categorized as MHO or metabolically unhealthy obesity (MUO) based on insulin resistance. CMRFs were assessed using blood pressure (BP); levels of triglycerides, high-density lipoprotein cholesterol (HDL-C), and fasting plasma glucose; or a diagnosis of diabetes mellitus. Differences in cIMT values were evaluated according to the metabolic phenotype and factors associated with cIMT.

RESULTS

Among the 111 participants (80 boys, 72.1%), 23 (20.7%) were classified as MHO and 88 (79.3%) as MUO. The MHO group exhibited lower glycated hemoglobin and triglyceride levels and higher HDL-C levels compared to those exhibited by the MUO group (all P<0.01). The cIMT values did not differ significantly between the MHO and MUO groups. The high cIMT tertile group revealed higher systolic BP compared to that exhibited by the low cIMT tertile group (123.7±2.1 mmHg vs. 116.9±1.6 mmHg, P=0.028). Mean cIMT was positively correlated with age (β=0.009) and body mass index (BMI) (β=0.033) after adjusting for covariates (both P<0.05).

CONCLUSION

In overweight and obese Korean adolescents, cIMT was associated with age and BMI but not with metabolic phenotype or CMRFs. Further research is warranted to determine the relationship between cIMT during adolescence and cardiovascular outcomes during adulthood.

What is the disease burden from childhood and adolescent obesity?: a narrative review

The prevalence of childhood and adolescent obesity has increased and exacerbated during the coronavirus disease 2019 pandemic, both in Korea and globally. Childhood and adolescent obesity poses significant risks for premature morbidity and mortality. The development of serious comorbidities depends not only on the duration of obesity but also on the age of onset. Obesity in children and adolescents affects almost all organ systems, including the endocrine, cardiovascular, gastrointestinal, reproductive, nervous, and immune systems. Obesity in children and adolescents affects growth, cognitive function, and psychosocial interactions during development, in addition to aggravating known adult comorbidities such as type 2 diabetes mellitus, hypertension, dyslipidemia, nonalcoholic fatty liver disease, obstructive sleep apnea, and cancer. Childhood and adolescent obesity are highly associated with increased cardiometabolic risk factors and prevalence of metabolic syndrome. The risk of cardiovascular and metabolic diseases in later life can be considerably decreased by even a small weight loss before the onset of puberty. Childhood and adolescent obesity is a disease that requires treatment and is associated with many comorbidities and disease burdens. Therefore, early detection and therapeutic intervention are crucial.

Effective and appropriate use of weight loss medication in pediatric obesity: a narrative review

Over the past few decades, there has been a notable increase in the incidence of pediatric obesity, which is a significant public health concern. Children who are obese have a greater risk of type 2 diabetes, hypertension, dyslipidemia, polycystic ovary syndrome, obstructive sleep apnea, and adult obesity. Lifestyle modification therapy is typically the initial approach to treat pediatric obesity. For patients who do not achieve success with lifestyle modification therapy alone, pharmacotherapy is the next logical treatment option. When selecting an anti-obesity medication (AOM), it is essential to first ascertain the medical background of the patient, including current medications and obesity-associated comorbidities. Evaluation of obesity phenotypes in patients may also be beneficial. AOMs for pediatric obesity include metformin, orlistat, glucagon-like peptide 1 agonists, phentermine, and the phentermine/topiramate combination. Sufficient lifestyle modification therapy should be administered before considering pharmacotherapy and continued after the initiation of AOM. To ensure healthy development, monitoring growth and puberty development during anti-obesity treatments is essential.

The prevalence and prevention strategies of pediatric obesity: a narrative review

Pediatric obesity has rapidly increased globally over the past few decades, including in Korea. We aimed to discuss trends in the prevalence of pediatric obesity and effective prevention strategies. Its prevalence has markedly increased in most high-income nations. According to recent reports, this increase has slowed in developed countries, but the levels remain alarmingly high. In Korea, the rate of pediatric obesity has surged notably since the 1990s; however, since the 2000s, this increase has become more gradual. According to recently published 2017 growth charts, the prevalence of pediatric obesity in Korea varies slightly depending on the data source. The National School Health Examination data showed that pediatric obesity gradually increase from 11.5% in 2014 to 15.1% in 2019, and after the coronavirus disease 2019 pandemic, it sharply increased to 19% in 2021. Based on data from the Korea National Health and Nutrition Examination Survey, the prevalence of pediatric obesity gradually increased from 10.8% in 2017 to 13.6% in 2019. This trend, which accelerated sharply to 15.9% in 2020 and 19.3% in 2021, was especially severe in boys and older children. Pediatric obesity not only affects health during childhood but also increases the risk of developing obesity and associated health conditions in adulthood. Despite ongoing research on treatment options, obesity prevention and control remain challenging. Hence, prioritizing early intervention and prevention of pediatric obesity through healthy eating habits and lifestyles is crucial. This requires intervention at the individual, family, school, and community levels.

Risk Factors for Overweight and Obesity in Later School-Aged Children: Focus on Lifestyle Behaviours and Psychosocial Characteristics

The study analysed the 12th wave (2019) of data from the Panel Study on Korean Children conducted by the Korea Institute of Child Care and Education. A total of 1174 children were selected as the subjects of the study. The results concerning the identifying factors influencing overweight and obesity in later school-aged children revealed that when compared to boys, girls were 1.66 times more likely to be overweight or obese. Moreover, for every one-hour increase in media usage time, the likelihood of being overweight or obese increased by 1.23 times, and for every one-point increase in body dissatisfaction, the probability of being overweight or obese increased by 2.07 times. However, among personality traits, neuroticism was associated with a 0.96 times lower likelihood of being overweight or obese. These findings underscore the significance of considering not only lifestyle factors but also psychosocial characteristics such as body dissatisfaction and neuroticism as predictive factors for overweight and obesity in later school-aged children, providing a basis for intervention.

Macronutrients modified dietary intervention in the management of overweight/obese children and adolescents: a systematic review

The prevalence of obesity in adults and children is rapidly increasing worldwide. Obesity is among the main causes of chronic diseases and various problems, including economic consequences and they can also be affected by genetic, environmental, psychological, and socioeconomic factors. Dietary modification is a well-known and important factor in weight control, in particular, dietary macronutrient composition, food selection, dietary patterns, and energy restriction can affect weight reduction. Therefore, this systematic review aims to provide basic evidence for identifying the optimal macronutrient composition for managing obesity in Korean children and adolescents. We searched literature through an international database, studies were selected using our eligibility criteria and quality was assessed via a risk of bias tool. In our results, several studies have demonstrated that dietary macronutrient modifications affect body composition and metabolic markers in children and adolescents. In contrast, hypocaloric diets, regardless of macronutrient composition, are reportedly effective for weight loss in obese children. However, these findings were based on intervention studies that examined the association between dietary macronutrient composition and obesity in non-Korean children and adolescents. Therefore, in the future, more intervention studies are needed to elucidate this relationship and evidence between macronutrients and obesity in Korean children and adolescents.

2023 Obesity Fact Sheet: Prevalence of Obesity and Abdominal Obesity in Adults, Adolescents, and Children in Korea from 2012 to 2021

Background

The 2023 Obesity Fact Sheet aims to present an updated overview of obesity prevalence across all age groups, including children and adolescents.

Methods

This study included individuals aged ≥20 years (n=16,941,423 in 2021) who underwent health checkups provided by the Korean National Health Insurance Service between 2012 and 2021. The prevalence of obesity and abdominal obesity was standardized by age and sex using data from the 2010 population and housing census. For children and adolescents (6 to 18 years) (n=884 in 2021), we used the Korea National Health and Nutrition Examination Survey (2012 to 2021), and obesity was defined by the corresponding sex- and age-specific body mass index percentile of 95th or greater based on the 2017 Korean National Growth Chart for Children and Adolescents.

Results

The overall prevalence of obesity in 2021 is 38.4% (49.2% in men and 27.8% in women), which is a 1.27-fold increase from 30.2% in 2012. The prevalence of obesity has increased across all age groups, particularly among those aged 20, 30, and 80 years. The prevalence of class III obesity substantially increased from 0.35% (men) and 0.42% (women) in 2012 to 1.21% and 0.97% in 2021, with 3.46- and 2.31-fold increases, respectively. This increase was particularly pronounced in young adults. The prevalence of obesity in children and adolescents has surged from 9.7% in 2012 to 19.3% in 2021, with a greater increase among boys.

Conclusion

Our study provides information on the current status of obesity prevalence based on the 2023 Obesity Fact Sheet, emphasizing the urgency of implementing timely strategies to reverse this increasing trend.

Pediatric obesity and development of the penis and testis

PURPOSE

Pediatric obesity is increasing in many countries as socioeconomic status improves and the consumption of high calorie food increases. Thus, effect of obesity on genital development is an important topic. This study aimed to determine relationships of body mass index (BMI) with penile parameters and testicular volume in pediatric patients without penile or testicular abnormalities.

MATERIALS AND METHODS

Data from 1,499 male pediatric patients from our center were analyzed. Patients with penile or testicular abnormalities were excluded. Their age ranged from 2 to 18 years. These patients were divided into two groups based on their BMI: normal BMI (5th-85th percentile) and high BMI (≥85th percentile). Factors used in analysis included age, anthropometric indicators, baseline penile length (BPL), stretched penile length (SPL), penile circumference (PC), and mean testicular volume. These same parameters were analyzed for different age groups.

RESULTS

Pediatric patients with normal BMI showed longer BPL and SPL than patients with high BMI (p<0.05). However, PC and mean testicular volumes showed no significant difference between the two groups. BPL was significantly longer in the normal BMI group starting at ten years of age. SPL was significantly longer in the normal BMI group starting at eleven years of age.

CONCLUSIONS

Our study confirms that having a higher BMI during childhood has a negative effect on penile length. However, there was no significant relationship between BMI and PC or testicular volume.

Inverted U-Shaped Relationship between Obesity Parameters and Bone Mineral Density in Korean Adolescents

As the association between obesity and bone health remains controversial in children and adolescents, we investigate the effects of obesity parameters on bone mineral density (BMD) in 2060 Korean adolescents who participated in the 2008-2011 Korea National Health and Nutrition Examination Survey (KNHANES). Multiple regression analysis and analysis of covariance (ANCOVA) were conducted to examine both the linear and non-linear associations between total-body-less-head (TBLH) BMD and four obesity parameters: body mass index, waist circumference, waist-to-height ratio, and total-body fat mass (FM). In a multiple linear regression analysis adjusted for age, menarcheal status (in females only), and total-body lean mass, there was no significant linear association between obesity parameters and TBLH BMD, except for total-body FM in males. However, upon adding a second-order polynomial term for each obesity parameter, a significant quadratic relationship between all obesity parameters and TBLH BMD was observed, with the corresponding quadratic term being negative. The results of ANCOVA also revealed an inverted U-shaped relationship between each obesity parameter and TBLH BMD. Our findings suggest the existence of an optimal range of obesity parameters for developing or maintaining optimal bone health in Korean Adolescents. Deviation from this range, in either direction (being underweight or having obesity), may compromise bone health.

Association of Infant Feeding Characteristics With Dietary Patterns and Obesity in Korean Childhood

OBJECTIVES

Young children's feeding characteristics can play an important role in eating habits and health during later childhood. This study was conducted to examine the associations of feeding characteristics with dietary patterns and obesity in children.

METHODS

This study utilized data from the Korea National Health and Nutrition Examination Survey conducted between 2013 and 2017. In total, 802 toddlers were included, with information on their demographic characteristics, feeding practices and duration, and 24-hour recall obtained from their parents. Feeding characteristics were categorized into feeding type, duration of total breastfeeding, duration of total formula feeding, duration of exclusive breastfeeding, and age when starting formula feeding. Dietary patterns were identified based on factor loadings for the food groups for 3 major factors, with "vegetables & traditional," "fish & carbohydrates," and "sweet & fat" patterns. Overweight/obesity was defined as ≥85th percentile in body mass index based on the 2017 Korean National Growth charts for children and adolescents. Multiple regression analysis was conducted to examine associations between feeding characteristics and dietary patterns. The association between dietary patterns and obesity was analyzed using multivariable logistic regression analysis.

RESULTS

The early introduction of formula feeding was inversely associated with the "vegetables & traditional" pattern (β=-0.18; 95% confidence interval [CI], -0.34 to -0.02). A higher "vegetables & traditional" intake was associated with a lower risk of obesity (odds ratio, 0.48; 95% CI, 0.24 to 0.95).

CONCLUSIONS

Feeding characteristics are associated with dietary patterns in later childhood, and dietary patterns were shown to have a potential protective association against obesity.

Increase of Prevalence of Obesity and Metabolic Syndrome in Children and Adolescents in Korea during the COVID-19 Pandemic: A Cross-Sectional Study Using the KNHANES

(1) Background: The aim of this study was to evaluate the prevalence of obesity and metabolic syndrome since the COVID-19 pandemic outbreak utilizing representative data on youth aged 2-18 years from the Korean National Health and Nutrition Examination Surveys (KNHANES) conducted in 2019-2020. (2) Methods: The survey consists of three parts: health interviews, health examinations, and nutrition surveys. From the 2019 and 2020 surveys, 1371 (2-9 years = 702 and 10-18 years = 669) and 1124 (2-9 years = 543 and 10-18 years = 581) individuals were included in the analysis. (3) Results: The mean body mass index (BMI) increased significantly among youth aged 2-9 years from 16.53 kg/m² in 2019 to 17.1 kg/m² in 2020 (p < 0.01). In youth aged 10-18 years, the BMI was found to increase slightly from 21.25 kg/m² in 2019 to 21.41 kg/m² in 2020 (p = 0.64). The increasing prevalence of extreme obesity was significant in girls, especially those aged 2-9 years (p < 0.01). However, extreme obesity had increased in 10-18-year-old boys (p = 0.08). The overall prevalence of metabolic syndrome in adolescents increased from 3.79% to 7.79% during the COVID-19 pandemic (p = 0.01). (4) Conclusions: We observed that the prevalence of obesity and metabolic syndrome among children and adolescents has increased after the COVID-19 outbreak. This is believed to be associated with an increase in the rate of early comorbidities in adulthood. The prevention of the progression of pediatric obesity has recently become an urgent public health concern in Korea.

Association between the Dietary Phytochemical Index and Lower Prevalence of Obesity in Korean Preschoolers

Little is known regarding Korean preschooler dietary phytochemical index (DPIs). We used the 24 h recall data of 1196 participants aged 3-5 years from the Korea National Health and Nutrition Examination Survey to study the association between dietary food intake and obesity prevalence. The amount of dietary intake by food group was compared according to sex and DPI quartile. Multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression models. The average total DPI and energy from phytochemical food groups were not significantly different according to sex, although boys had a higher total daily food intake. Different inclinations between DPI quartiles and amount of intake were observed in the food groups; specifically, beans showed a higher intake difference between Q1 and Q4 for boys than in the other food groups. The highest DPI quartile had a significantly lower obesity prevalence than the lowest DPI quartile in all models for boys only when obesity prevalence by weight percentile was analyzed (Model 3, OR: 0.287, 95% CI: 0.095-0.868, p for trend < 0.05). Our results suggest a high DPI could help prevent obesity in preschoolers.

Trends in socioeconomic inequalities in obesity among Korean adolescents: the Korea Youth Risk Behavior Web-based Survey (KYRBS) 2006 to 2020

OBJECTIVES

This study investigated recent trends in the prevalence of obesity among Korean adolescents and explored socioeconomic disparities in obesity.

METHODS

This study used annual self-reported data on height, weight, and socioeconomic information from the Korea Youth Risk Behavior Web-based Survey from 2006 to 2020. With a 95.8% response rate, the sample consisted of 818,210 adolescents. Obesity prevalence was calculated according to 4 socioeconomic indicators (household income, father's educational attainment, mother's educational attainment, and urbanicity). Socioeconomic inequality was quantified using the relative index of inequality (RII).

RESULTS

The overall prevalence of obesity increased, doubling from 5.9% in 2006 to 11.7% in 2020. Boys and high school students showed a higher prevalence. The RIIs in household income and parental educational attainments significantly increased with time, indicating a growing inequality in obesity. Socioeconomic disadvantages had a greater influence on obesity among girls. The most recent RII values for boys were 1.25 for income, 1.79 for the father's education, and 1.45 for the mother's education, whereas the corresponding values for girls were 2.49, 3.17, and 2.62, respectively.

CONCLUSIONS

These findings highlight growing inequalities in adolescent obesity according to household income and parental educational attainments, especially for girls and middle schoolers.

Pediatric management challenges of hyperglycemic hyperosmolar state: case series of Korean adolescents with type 2 diabetes

The hyperglycemic hyperosmolar state (HHS) is considered the most fatal complication of type 2 diabetes mellitus (DM). The number of case reports describing pediatric HHS has increased recently in parallel with obesity and the prevalence of type 2 DM in pediatric patients. In this study, we investigated the patient characteristics and outcomes of HHS in 9 adolescents with obesity and type 2 DM. Almost all patients exhibited mixed clinical features of HHS and diabetic ketoacidosis (DKA), including characteristics such as hyperosmolality and ketoacidosis. These features made definitive diagnosis difficult; 5 out of 9 patients were initially diagnosed with DKA and were treated accordingly. Patients who were initially diagnosed with HHS received a more vigorous and appropriate fluid replacement than other patients did. No patients died, although 3 exhibited complications, such as arrhythmia, acute kidney injury requiring renal replacement therapy, rhabdomyolysis, and acute pancreatitis. Hyperosmolality with consequent severe dehydration is considered a significant factor contributing to the outcomes of patients with HHS. Therefore, early recognition of hyperosmolality is crucial for an appropriate diagnosis and adequate fluid rehydration to restore perfusion in the early period of treatment to improve patient outcomes for this rare but serious emerging condition in pediatric patients.

Heat-Killed Enterococcus faecalis Inhibit FL83B Hepatic Lipid Accumulation and High Fat Diet-Induced Fatty Liver Damage in Rats by Activating Lipolysis through the Regulation the AMPK Signaling Pathway

Continuous consumption of high-calorie meals causes lipid accumulation in the liver and liver damage, leading to non-alcoholic fatty liver disease (NAFLD). A case study of the hepatic lipid accumulation model is needed to identify the mechanisms underlying lipid metabolism in the liver. In this study, the prevention mechanism of lipid accumulation in the liver of Enterococcus faecalis 2001 (EF-2001) was extended using FL83B cells (FL83Bs) and high-fat diet (HFD)-induced hepatic steatosis. EF-2001 treatment inhibited the oleic acid (OA) lipid accumulation in FL83B liver cells. Furthermore, we performed lipid reduction analysis to confirm the underlying mechanism of lipolysis. The results showed that EF-2001 downregulated proteins and upregulated AMP-activated protein kinase (AMPK) phosphorylation in the sterol regulatory element-binding protein 1c (SREBP-1c) and AMPK signaling pathways, respectively. The effect of EF-2001 on OA-induced hepatic lipid accumulation in FL83Bs enhanced the phosphorylation of acetyl-CoA carboxylase and reduced the levels of lipid accumulation proteins SREBP-1c and fatty acid synthase. EF-2001 treatment increased the levels of adipose triglyceride lipase and monoacylglycerol during lipase enzyme activation, which, when increased, contributed to increased liver lipolysis. In conclusion, EF-2001 inhibits OA-induced FL83B hepatic lipid accumulation and HFD-induced hepatic steatosis in rats through the AMPK signaling pathway.

Age at menarche of adolescent girls and the neighbourhood socioeconomic status of their school area

PURPOSE

To assess the association between abnormal timing of menarche among adolescent girls and neighbourhood socioeconomic status of their school area.

MATERIALS AND METHODS

Our analysis included 187,024 girls aged 15-18 years from the Korea Youth Risk Behaviour Web-Based Survey (KYRBS) from 2007 to 2015. Early and late menarche were defined as menarche before 11 years and no menarche by age 14 years, respectively. The deprivation index values for the areas where the schools were located were used as an indicator of neighbourhood socioeconomic status based on the 2005 national census data. We calculated odds ratios (OR) for early and late menarche using a multinomial logistic regression model. Covariates included body mass index, parental education, single or stepparents, siblings, household wealth, year of birth, survey year, and urbanisation.

RESULTS

Mean age at menarche was 12 years. The overall proportions of early and late menarche were 11.3% and 3.3%, respectively. When divided into four quartile groups based on the socioeconomic deprivation index, 11.3% of girls in the most deprived quartile and 10.6% in the least deprived area showed early menarche. The prevalence of late menarche did not differ across the deprivation index quartiles of school area. Attendance at schools located in highly deprived areas was associated with up to 10% higher risk of early menarche. This positive association was not evident for late menarche.

CONCLUSION

Among contemporary Korean girls, socioeconomic deprivation of the school area was associated with earlier puberty. This finding highlights the potential role of the socioeconomic environment of schools in women's lifetime health.

Ongoing increasing trends in central precocious puberty incidence among Korean boys and girls from 2008 to 2020

BACKGROUND

Over the last few decades, there has been growing evidence of earlier onset and progression of puberty worldwide. This population-based longitudinal cohort study aimed to analyze the change in the annual incidence rate of central precocious puberty (CPP) among Korean children over the most recent decade, using the national registry data.

METHOD

The International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) and insurance claims for gonadotropin-releasing hormone agonist (GnRHa) treatment were used to identify CPP patients who were using the Korean Health Insurance Review & Assessment Service (HIRA) database between 2008 and 2020. Patients who began GnRHa therapy before the age of 9 and 10 for girls and boys, respectively, were included in the study.

RESULTS

A total of 6,906 boys and 126,377 girls were diagnosed with CPP between 2008 and 2020. The annual incidence of CPP increased by 83.3 times in boys (from 1.2 to 100 per 100,000 persons) and by 15.9 times in girls (from 88.9 to 1414.7 per 100,000 persons). The age-specific annual incidence of CPP increased remarkably more in older children than in younger ones; the 2020 CPP incidence among 9-year-old boys and 8-year-old girls reached 705.2 and 7,967.3 per 100,000 persons, respectively. The annual prevalence of CPP in boys and girls increased from 2.7 to 206.5 (76.5 times) and from 141.8 to 3439.9 (24.3 times) per 100,000 persons, respectively.

CONCLUSION

Based on GnRHa treatment insurance claims, our study suggests that the annual incidence of CPP has substantially increased in Korea during the past 13 years. These findings highlight the importance of meticulous judgment by doctors in determining GnRHa treatment.

Trends of overweight and obesity prevalence in school-aged children among Henan Province from 2000 to 2019

Objectives

Overweight and obesity are harmful to human health. However, the latest trends of Chinese childhood overweight and obesity prevalence are not available. The aim of this study was to examine the trends from 2000 to 2019 among students in China.

Methods

We analyzed data of 66,072 students in the Chinese National Survey on Students' Constitution and Health from 2000 to 2019. Overweight and obesity were defined based on the standard formulated by the International Obesity Task Force (IOTF standard), the World Health Organization (WHO standard), and the Working Group on Obesity in China (WGOC standard), respectively. The χ²-test was used to test the trends of overweight and obesity prevalence and logistic regression was conducted to evaluate the prevalence odds ratios of boys vs. girls and urban vs. rural areas.

Results

The prevalence of obesity/overweight and obesity combined was 6.03/23.58% (IOTF standard), 10.56/25.88% (WGOC standard) and 10.75/29.69% (WHO standard) in 2019. From 2000 to 2019, according to the WGOC standard, the prevalence increased from 2.51 to 10.56% for obesity and increased from 9.81 to 25.88% for overweight and obesity combined (P for trend < 0.001). Obesity/overweight and obesity were greater problems in boys than girls and urban than rural areas, but urban-rural differences decreased over time.

Conclusion

Overweight and obesity prevalence increased significantly in children and adolescents in China from 2000 to 2019. The prevalence of overweight and obesity in rural areas may contribute to a large percentage of children with overweight and obesity.

Cardiometabolic risk factors and metabolic syndrome based on severity of obesity in Korean children and adolescents: data from the Korea National Health and Nutrition Examination Survey 2007-2018

PURPOSE

Data regarding cardiometabolic risk factors (CMRFs) and metabolic syndrome (MetS) by body mass index (BMI) category in Korean youth are sparse.

METHODS

Among the participants of the Korea National Health and Nutrition Examination Survey 2007-2018, 9,984 youth aged 10-18 years were included in the study. Participants were classified into 4 groups based on BMI status: normal weight, overweight, class I, and class II/III obesity. CMRF prevalence, including total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, blood pressure, fasting glucose, glycated hemoglobin, and MetS, were determined using the International Diabetes Federation (IDF) and modified National Cholesterol Education Program-Adult Treatment Panel (NCEP-ATP) III criteria based on BMI category.

RESULTS

The prevalence of overweight, class I, class II, and class III obesity was 9.52%, 7.73%, 2.10%, and 0.32%, respectively. Mean CMRF values increased with BMI, except high-density lipoprotein cholesterol. Age- and sex-adjusted odds ratios (ORs) for prediction of CMRFs also increased with BMI. Adjusted ORs for MetS among overweight, class I, and class II/II obesity were 54.2, 283.3, and 950.3 for IDF criteria and 9.56, 37.9, and 126.8 for NCEP-ATP III criteria, respectively (all p<0.001).

CONCLUSION

Class II and III obesity in Korean children and adolescents was associated with significantly increased CMRF and MetS prevalence. Therefore, it can be useful to measure CMRFs in obese children and adolescents. Further studies are required to establish screening guidelines based on obesity severity.

Nutrition, Body Composition, and Blood Pressure in Children and Adolescents from the Korea National Health and Nutrition Examination Survey

We aimed to investigate the association between nutrition and blood pressure and the role that body composition plays in this relationship. Korea National Health and Nutrition Examination Survey data from the years 2008-2020 were reviewed. A total of 11,234 subjects (5974 boys and 5260 girls) aged 10-18 years of age were selected. We analyzed the correlation between nutrition (intakes of energy, protein, fat, carbohydrate, sodium, saturated fatty acid (SFA), unsaturated fatty acid (USFA), and dietary fiber (DF)) and body composition (height, weight, waist circumference (WC), body mass index (BMI), and waist to height ratio (WHtR)), and performed multiple regression analysis to find the independent correlation between body composition and blood pressure (BP). We then compared the correlation between nutrition and BP, with or without adjustment for body composition. The intakes of energy, protein, fat, carbohydrate, sodium, and USFA had positive associations with height, weight, WC, and BMI. Systolic BP (SBP) and diastolic BP (DBP) were independently positively correlated with height and BMI. The intakes of energy, protein, fat, carbohydrate, sodium, and SFA had positive correlations with SBP and DBP, which disappeared when additionally adjusted for BMI and height. In conclusion, nutrition seems to affect BP via height and BMI in Korean children and adolescents.

Predicting South Korean adolescents vulnerable to obesity after the COVID-19 pandemic using categorical boosting and shapley additive explanation values: A population-based cross-sectional survey

OBJECTIVE

This study identified factors related to adolescent obesity during the COVID-19 pandemic by using machine learning techniques and developed a model for predicting high-risk obesity groups among South Korean adolescents based on the result.

MATERIALS AND METHODS

This study analyzed 50,858 subjects (male: 26,535 subjects, and female: 24,323 subjects) between 12 and 18 years old. Outcome variables were classified into two classes (normal or obesity) based on body mass index (BMI). The explanatory variables included demographic factors, mental health factors, life habit factors, exercise factors, and academic factors. This study developed a model for predicting adolescent obesity by using multiple logistic regressions that corrected all confounding factors to understand the relationship between predictors for South Korean adolescent obesity by inputting the seven variables with the highest Shapley values found in categorical boosting (CatBoost).

RESULTS

In this study, the top seven variables with a high impact on model output (based on SHAP values in CatBoost) were gender, mean sitting hours per day, the number of days of conducting strength training in the past seven days, academic performance, the number of days of drinking soda in the past seven days, the number of days of conducting the moderate-intensity physical activity for 60 min or more per day in the past seven days, and subjective stress perception level.

CONCLUSION

To prevent obesity in adolescents, it is required to detect adolescents vulnerable to obesity early and conduct monitoring continuously to manage their physical health.

Etiology and Secular Trends in Primary Amenorrhea in 856 Patients: A 17-Year Retrospective Multicenter Study in Korea

BACKGROUND

This study was performed to evaluate etiologies and secular trends in primary amenorrhea in South Korea.

METHODS

This retrospective multi-center study analyzed 856 women who were diagnosed with primary amenorrhea between 2000 and 2016. Clinical characteristics were compared according to categories of amenorrhea (hypergonadotropic/hypogonadotropic hypogonadism, eugonadism, disorders of sex development) or specific causes of primary amenorrhea. In addition, we assessed secular trends of etiology and developmental status based on the year of diagnosis.

RESULTS

The most frequent etiology was eugonadism (39.8%). Among specific causes, Müllerian agenesis was most common (26.2%), followed by gonadal dysgenesis (22.4%). Women with hypergonadotropic hypogonadism were more likely to have lower height and weight, compared to other categories. In addition, the proportion of cases with iatrogenic or unknown causes increased significantly in hypergonadotropic hypogonadism category, but overall, no significant secular trends were detected according to etiology. The proportion of anovulation including polycystic ovarian syndrome increased with time, but the change did not reach statistical significance.

CONCLUSION

The results of this study provide useful clinical insight on the etiology and secular trends of primary amenorrhea. Further large-scale, prospective studies are necessary.

Temporal trends in the prevalence of metabolically healthy overweight and obesity in Korean youth: data from the Korea National Health and Nutrition Examination Survey 2011-2019

PURPOSE

Metabolically healthy overweight/obesity (MHO) and metabolically unhealthy overweight/obesity (MUO) are distinct clinical phenotypes classified by the presence of cardiometabolic risk factors in an individual. In the present study, we investigated temporal trends in the prevalence of MHO in Korean adolescents using nationally representative data.

METHODS

Data from the Korea National Health and Nutrition Examination Survey 2011-2019 were used in this study. A total of 5,667 adolescents (3,014 boys, 53.2%) aged 10-18 years was included in this study. MHO was defined as a body mass index ≥85th percentile for the corresponding age and sex and absence of any cardiometabolic risk factors.

RESULTS

The prevalence of overweight/obesity showed an increasing trend from 18.8% (boys 17.3% and girls 20.6%) in 2011 to 23.7% (boys 24.0% and girls 23.5%) in 2019 (p for trend=0.045). The overall prevalence of MHO during 2011-2019 was 39.2%, which was higher in girls than in boys (boys 33.5%, girls 46.2%, p<0.001), and the change in prevalence of MHO from 2011 to 2019 (from 34.8% to 35.7%) was not significant. Among MUO, the most prevalent cardiometabolic risk factor was dysglycemia (48.8%), followed by elevated blood pressure (41.5%), low high-density lipoprotein cholesterol (35.0%), and high triglycerides (29.7%).

CONCLUSION

We observed a high prevalence of MHO in Korean youth with overweight/obesity. Although the prevalence of overweight/obesity increased, the prevalence of MHO was stable during 2011-2019. A risk-stratified approach based on metabolic health status can help reducing the medical and socioeconomic costs associated with obesity treatment.

Changes in the adiposity level and prevalence of overweight/obesity among children from Kraków (Poland) within the last decade (from 2010 to 2020)

The aim of this study was to assess the changes in the prevalence of overweight, obesity and high adiposity in children and adolescents from Krakow (Poland), between the years 2010 and 2020. Two cross-sectional series of anthropometric measurements were carried out in 2010 and 2020. Analysed characteristics included: body height and weight, BMI (Body Mass Index), body adiposity (%BF). The subjects were categorised according to their BMI (underweight, normal weight, overweight, obesity), as well as %BF (low, normal, high body fat).The research was conducted in randomly selected primary schools in Krakow (Poland). Studied cohorts (8-15 years of age), which represented four of the traditional residential districts: Śródmieście, Podgórze, Krowodrza and Nowa Huta. Among the girls, there was a negative secular trend regarding the prevalence of underweight and obesity. On the other hand, there also was a positive trend concerning the prevalence of overweight and low and high body fat. In boys, there was a negative secular trend regarding the prevalence of underweight and low adiposity. There was also a generally positive secular trend regarding the prevalence of overweight, obesity as well as high adiposity in boys. The findings of this study are particularly significant because detailed knowledge of the prevalence of overweight/obesity in childhood and adolescence is crucial for the future health of entire populations. Further studies should also take into account the levels of physical fitness and activity of the examined population.

Difference in the Prevalence of Elevated Blood Pressure and Hypertension by References in Korean Children and Adolescents

The prevalence of pediatric hypertension and obesity has increased over the past decades. Pediatric hypertension and obesity are associated with adult hypertension, metabolic syndrome, and cardiovascular disease. There are two main pediatric blood pressure (BP) classification guidelines, the "Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents" (AAP 2017) and "2016 European Society of Hypertension guidelines for the management of high BP in children and adolescents" (ESH 2016). No study has classified Korean youths with cardiometabolic risk. This study analyzed the prevalence of high BP according to AAP 2017 (elevated BP and hypertension) and ESH 2016 (prehypertension and hypertension) in Korean children. Additionally, the cardiometabolic risk factors (CMRFs) were compared between children who were hypertensive in AAP 2017 but normotensive in ESH 2016 (upward reclassified) to those who were normotensive in both AAP 2017 and ESH 2016. Data were extracted from the Korea National Health and Nutrition Examination Survey, 2016-2018. A total of 1,858 children aged 10-17 years were included in the analysis. The prevalence of elevated BP/prehypertension and hypertension was 4.1 and 6.5% by ESH 2016, and 8.9 and 9.4% by AAP 2017 in Korean youth, respectively. The AAP 2017 reclassified 11.9% of youth in the upper BP class. When those upward reclassified youth were compared to those who were normotensive in both AAP 2017 and ESH 2016, reclassified youth were male predominant (77.1 vs. 49.6%, p < 0.001), older (14.6 vs. 13.8, p < 0.001) and showed higher body mass index (BMI) z-score (0.77 vs. 0.15, p < 0.001) and more overweight/obesity (14.0/30.6 vs. 13.3/6.4%, p < 0.001) and severe CMRFs (triglyceride 83.2 vs. 72.9 mg/dL, p = 0.011; high-density lipoprotein cholesterol 47.3 vs. 51.1 mg/dL, p < 0.001; alanine transaminase 21.7 IU/L vs. 14.7 IU/L, p = 0.001, uric acid 5.89 vs. 5.22 mg/dL, p < 0.001; metabolic syndrome 13.2 vs. 1%, p < 0.001). In conclusion, AAP 2017 showed a higher prevalence of abnormal BP in Korean youth, and those upward reclassified by AAP 2017 were more obese and had severe CMRFs than normotensive Korean children. The AAP 2017 could allow the early detection of Korean youth with more CMRFs.

Prevalence of Type 2 Diabetes Mellitus among Korean Children, Adolescents, and Adults Younger than 30 Years: Changes from 2002 to 2016

BACKGROUND

Despite the importance of and social concern regarding prevention of diabetes at younger ages, limited data are available. This study sought to analyze changes in the prevalence of type 2 diabetes mellitus (T2DM) in Koreans younger than 30 years according to sex, age, and level of income.

METHODS

The dataset analyzed in this study was derived from health insurance claims recorded in the National Health Insurance Service (NHIS) database. Participants' level of income was categorized as low (quintile 1, <20% of insurance premium) or others (quintile 2-5).

RESULTS

In males and females, the prevalence of T2DM per 10,000 people steadily increased from 2.57 in 2002 to 11.41 in 2016, and from 1.96 in 2002 to 8.63 in 2016. The prevalence of T2DM in girls was higher in the age group of 5 to 14 years. Even though the prevalence was higher among those older than 20 years, the increase had started earlier, in the early 2000s, in younger age group. Adolescents aged 10 to 19 years in low-income families showed a remarkable increase in prevalence of T2DM, especially in boys.

CONCLUSION

The prevalence of T2DM in young Koreans increased more than 4.4-fold from 2002 to 2016, and the increase started in the early 2000s in younger age groups and in low-income families. This is the first study to examine the trend in prevalence of T2DM in children, adolescents, and young adults in Korea. Future studies and collaborations with social support systems to prevent T2DM at an early age group should be performed.

Risk Factors for Obesity in Five-Year-Old Children: Based on Korean National Health Insurance Service (NHIS) Data

This study aimed to identify the risk factors for obesity in five-year-old children using data from the database of the Korean National Health Insurance Service. We identified 26,047 children who underwent the sixth screening (at age 5) from the 2017 National Health Screening Program for Infant and Children and for whom data from the fourth screening (at age 3) database and the mothers’ health screening and eligibility database were available. To identify the risk factors of obesity, odds ratios and 95% confidence intervals were calculated by a hierarchical multiple logistic regression. Female sex, a birth weight of over 4 kg, the “caution/refer” remark during developmental screening at ages three and five, maternal obesity, and a middle-level income were risk factors for obesity in the subjects. Good appetite, high consumption of milk, heavy intake of sweet food at age three, speedy eating, irregular meals and snack times, large single-meal quantities, heavy intake of oily and salty food, and not performing physical exercise at age five were also considered significant risk factors. For early intervention efforts to prevent childhood obesity, modifiable behavioral factors and other obesity risk factors identified in this study could be used to target high-risk children and dietary behaviors.

Effectiveness of obesity interventions among South Korean children and adolescents and importance of the type of intervention component: a meta-analysis

BACKGROUND

Various interventions have been tested to prevent or treat childhood obesity in South Korea. However, the overall effect of those interventions is unclear, as very few reviews and meta-analyses were specific to Korean children and adolescents.

PURPOSE

We aimed to examine the overall effect of obesity interventions among Korean children and adolescents, while also examining differences by sex, age group, baseline weight category, intervention duration, number of intervention components, and type of intervention components.

METHODS

A meta-analysis was conducted for all intervention studies sampling Korean children and adolescents, with at least one control group and one month of follow-up, published between January 2000 and August 2020. Cohen d was calculated as an effect size for treatment effect, using the standardized difference between intervention group's body mass index (BMI) change and control group's BMI change.

RESULTS

The final sample included 19 intervention studies with 2,140 Korean children (mean age, 12.2 years). Overall, interventions were strongly favored over their controls (d=1.61; 95% confidence interval [CI], 1.12-2.09). The subgroup analysis showed that interventions with at least one physical activity component (d=2.43; 95% CI, 1.63-3.24) were significantly better than those that did not include physical activity (d=0.02; 95% CI, -0.26 to 0.31).

CONCLUSION

Type of intervention component appeared important, though no differential association was observed by sex, age, baseline weight category, intervention duration, and number of intervention components. Korean and non-Korean interventions may be substantively different. Additional studies are needed to understand why and how Korean interventions differ from non-Korean interventions.

Effects of a 12-Week Diet versus Diet plus Aerobic and Resistance Exercise Program on Acylated and Desacylated Ghrelin, and Ghrelin O-Acyltransferase in Adolescent Girls with Obesity

This study investigated the effects of a 12-week diet versus diet plus aerobic and resistance exercise programme on acylated ghrelin (AG), desacylated ghrelin (DAG), and ghrelin O-acyltransferase (GOAT) concentrations in girls with obesity. We randomised 30 adolescents with obesity to a 12-week aerobic and resistance exercise group (EG) or a control group (CG). At baseline and at 4, 8, and 12 weeks, we measured their body composition, lipid profile, glucose, AG, DAG, and GOAT concentrations. In the EG, the body fat percentage decreased by 2.37% and was significantly lower than that in the CG. The DAG concentrations significantly increased by 48.3% and 27.4% in the EG and CG, respectively. At 4, 8, and 12 weeks, DAG concentrations were significantly higher in the EG than in the CG. AG concentrations were higher at week 12 than at baseline in both groups. In both groups, the GOAT concentrations increased at weeks 8 and 12; however, no between-group differences were observed in the changes in GOAT concentrations. This study showed increased DAG concentrations and non-significant changes in AG and GOAT concentrations after a 12-week aerobic and resistance exercise programme in girls with obesity. These findings suggest that an aerobic and resistance exercise programme influences appetite-regulating hormones, mainly through changes in DAG concentrations.

Severe Obesity in Children and Adolescents: Metabolic Effects, Assessment, and Treatment

Childhood obesity has been increasing steadily in recent decades, and severe childhood obesity has emerged as a major public health problem both nationally and internationally. A current concern is that lockdown due to the coronavirus disease 2019 (COVID-19) pandemic could exacerbate the spread of childhood obesity and increase the gap in obesity risk. Recent research results indicate the aggravation of obesity after school closures. The consequences of severe childhood obesity are more devastating than those of mild to moderate obesity. Children with severe obesity are at greater risk than others for hypertension, type 2 diabetes, metabolic syndrome, non-alcoholic fatty liver disease, atherosclerosis, and adult obesity. Accurately assessing and diagnosing a child with severe obesity is the key to implementing successful therapy. A detailed and accurate patient history and physical examination are important to discriminate monogenic obesity and metabolic syndrome diagnoses from severe obesity without an underlying cause. Psychosocial factors, including eating behaviors, should be assessed to facilitate better weight management outcomes. Treatment options for severe pediatric obesity include lifestyle modification therapy, pharmacotherapy, and metabolic and bariatric surgery. However, lifestyle modification should be the priority. Although progress has been made, safe and effective treatment for severe pediatric obesity is still challenging. More efforts and innovations are needed to find a solution for the huge medical and emotional burden that these children and their families carry. Public health organizations also need to make efforts to encourage and normalize healthy eating habits and exercise to prevent severe obesity in childhood.

Regional Adolescent Obesity and Overweight Status in Korea from 2018-2019: Comparison between Two Data Sources

Difference in the regional adolescent obesity level may cause a notable health inequality between regions since it significantly affects adulthood health status. This study examined 2018 and 2019 regional obesity and overweight status of adolescents aged 12 to 18 by comparing two cross sectional population-based data sources, the Korea Youth Risk Behavior Web-based Survey (KYRBS) and the National Student Health Examination (NSHE). Prevalence was estimated by calculating weighted percentages and 95% confidence intervals. Correlations in the relative rankings of each municipality were determined by computing Spearman correlation coefficients (r_s), and prevalence discrepancies between the data sources were visualized by simple correlation graphs. The geographical distributions of adolescent obesity and overweight status showed no perfect concordances between the data sources regardless of sexes and survey years. For adolescent obesity status, there were significant difference between the least and the most obese regions and r_s levels were fair to good with p-values less than 0.05, but the correlation graphs indicated body mass index (BMI) underreporting in the KYRBS. For adolescent overweight status, no significant similarities were defined between the data. These results can be used as a basis for the establishment of related policies.

Endocrine comorbidities of pediatric obesity

Pediatric obesity has become a serious public health issue. The prevalence of obesity in children and adolescents has increased worldwide and in Korea over several decades. Obese children are more likely to be obese adults with an increased cardiovascular risk. Therefore, maintaining a healthy weight and preventing obesity during childhood are of critical importance. Moreover, obese children and adolescents often have endocrine comorbidities such as prediabetes, type 2 diabetes, dyslipidemia, metabolic syndrome, polycystic ovary syndrome, and central precocious puberty. Hence, the early implementation of obesity management using a multidisciplinary team approach and screening for these comorbidities in obese children and adolescents are required with the appropriate management of each comorbidity and/or specialist referral.

Body Shape Indices in Adolescents Based on the 2009-2012 Korea National Health and Nutrition Examination Survey

A Body Shape Index (ABSI) is a recently proposed index for standardizing waist circumference (WC) for body mass index (BMI) and height in adults, using 2/3 and 1/2 as scaling exponents, respectively. However, ABSI has limited applicability to children and adolescents, as the relationship between height and weight changes with age and varies according to sex. This study aimed to investigate whether ABSI can be applied to adolescents and to analyze the relationships among BMI, WC, height, weight, and body shape index (BSI) in Korean adolescents. The data of 1023 adolescents aged 10-19 years from the 2009-2012 Korea National Health and Nutrition Examination Survey were collected. Body measurements (height, weight, WC, and BMI) were analyzed to estimate the BSI using log-linear regression. The scaling exponents for standardizing WC for weight and height were estimated according to age (per year) and sex. The scaling exponents for standardizing WC for weight and height were 0.698 and -1.090 for boys and 0.646 and -0.855 for girls, respectively. The exponents also differed according to age. BSI was negatively correlated with height, weight, and BMI in boys and girls, and these correlations differed in direction from those in adults. ABSI cannot be applied to adolescents. In adolescents, the BSI is dependent on age and sex and is associated with growth and puberty. Further studies are required to evaluate the association between BSI and other biomarkers, to improve its applicability as a parameter for predicting the risk of chronic diseases in adolescents.

Trends in Serum Lipid Profiles Among Korean Adolescents, 2007-2018

PURPOSE

An adverse lipid profile in adolescence often persists into adulthood, resulting in cardiovascular disease. We aimed to investigate the trends in the prevalence of adverse lipid profiles among Korean adolescents from 2007 to 2018.

PATIENTS AND METHODS

The data were obtained from 9044 adolescents aged 10-19 years who participated in the Korean National Health and Nutrition Examination Surveys (KNHANES) from 2007 to 2018. Fasting serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) levels were analyzed.

RESULTS

Significantly increasing trends in age-standardized prevalence of hypercholesterolemia [from 5.6% to 9.4% in boys (P = 0.004); from 8.1% to 12.4% in girls (P = 0.01)] and hyper-LDL-cholesterolemia [from 4.3% to 8.0% in boys (P = 0.003); from 6.6% to 9.7% in girls (P = 0.035)] were noted in both sexes. In contrast, the prevalence of hypo-HDL-cholesterolemia decreased significantly from 20.0% to 12.5% in boys (<0.001) and from 12.4% to 6.9% in girls (P < 0.001). There were no significant changes in the prevalence of hypertriglyceridemia and hyper-non-HDL-cholesterolemia in both sexes. Accordingly, the overall prevalence of dyslipidemia showed only a modest decline in boys (from 31.8% to 28.7%) and a stable trend in girls (from 28.9% to 28.2%).

CONCLUSION

The prevalence of hypercholesterolemia and hyper-LDL-cholesterolemia increased and that of hypo-HDL-cholesterolemia decreased among Korean adolescents over the recent 12 years. Further studies are needed to explain these trends and possible associations with lifestyle factors.

Evaluation of Agreement of Overweight Screening Criteria in Adolescents: Korean National Health and Nutrition Examination Surveys

Background

The increasing prevalence of overweight children and childhood obesity has led to early development of obesity-related diseases, including diabetes. Screening tests for type 2 diabetes in children indicate overweight as a major risk factor. Three overweight screening criteria have been considered: body mass index (BMI) >85th percentile (overweight 1, OW1), weight for height >85th percentile (OW2), and weight >120% of ideal for height (OW3). This study was conducted to evaluate the agreement in these screening criteria and the impact of increased use of screening methods.

Methods

Data were obtained from 965 Korean adolescents (521 boys and 444 girls). The subjects were classified into overweight and normal weight groups by the three above criteria. The agreement between criteria was evaluated using Cohen’s kappa value. Furthermore, we studied the relationships between the criteria and parameters of height, weight, BMI, and z score, based on the 2007 Korean growth chart.

Results

Totals of 188, 139, and 115 adolescents were classified as OW1, OW2, and OW3, respectively. The kappa values were 0.798, 0.710, and 0.891 for OW1 and OW2, OW1 and OW3, and OW2 and OW3, respectively. Weight, weight-z, BMI, and BMI-z were greater among subjects in all overweight groups compared to the normal weight group. However, the heights of the subjects did not differ between the three groups.

Conclusion

Active assessment of overweight status using OW1 could be improved by including more adolescents and focusing on the variability of individual growth and disease risk, even though substantial agreement was observed among the three overweight screening criteria.

Dietary intake and nutritional status of Korean children and adolescents: a review of national survey data

In Korea, several national cross-sectional surveys monitor the diet, nutritional status, and health status of children. This continual dedicated national surveillance system contributes to the identification of nutritional and health issues, establishment of public health policies, and development of nutrition recommendations. This paper provides recent information about the Korea National Health and Nutrition Examination Survey and the Korean Youth Risk Behavior Web-based Survey and describes key nationwide survey findings published in the last 5 years on infant feeding practices and the dietary intake and nutritional status of Korean infants, children, and adolescents. There have been increasing trends in children, and teenagers who skip breakfast, eat fast food, consume sugary drinks, have vitamin D deficiency, and are obese. This review will inform pediatricians, nutritionists, and other health care practitioners who track children's growth and development. It may also help researchers and policymakers identify diet-related policies and strategies for chronic disease prevention in Korean infants, children, and adolescents.

Trajectories in glycated hemoglobin and body mass index in children and adolescents with diabetes using the common data model

We evaluated trajectories of glycated hemoglobin (HbA1c) levels and body mass index z-scores (BMIz) for 5 years after diagnosis among Korean children and adolescents with type 1 diabetes (T1D) or type 2 diabetes (T2D) using the common data model. From the de-identified database of three hospitals, 889 patients < 15 years of age diagnosed with T1D or T2D (393 boys, 664 T1D patients) were enrolled. Diagnosis was defined as first exposure to antidiabetic drug at each center. Compared with T2D patients, T1D patients had lower BMIz at diagnosis (- 0.4 ± 1.2 vs. 1.5 ± 1.4, p < 0.001) and 3 months (- 0.1 ± 1.0 vs. 1.5 ± 1.5, p < 0.001), and higher HbA1c levels at diagnosis (10.0 ± 2.6% vs. 9.5 ± 2.7%, p < 0.01). After 3 months, HbA1c levels reached a nadir of 7.6% and 6.5% in T1D and T2D patients, respectively, followed by progressive increases; only 10.4% of T1D and 29.7% of T2D patients achieved the recommended HbA1c target (< 7.0%) at 60 months. T1D patients showed consistent increases in BMIz; T2D patients showed no significant change in BMIz during follow-up. Peri-pubertal girls with T1D had higher HbA1c and BMIz values. Achieving optimal glycemic control and preventing obesity should be emphasized in pediatric diabetes care.

Management of severe pediatric obesity

Background: Pediatric obesity has increased over the decades, and in particular, severe pediatric obesity has become a serious public health problem. A concern has arisen that the COVID-19 pandemic may exacerbate the incidence of childhood obesity.Current Concepts: The consequences of severe pediatric obesity are more devastating than those of moderate obesity. Children with severe obesity are at a greater risk for hypertension, type 2 diabetes, metabolic syndrome, non-alcoholic fatty liver disease, atherosclerosis, and adult obesity. Correct assessment and diagnosis of a child with severe obesity is key to successful therapy. A thorough history and physical examination are important in identifying monogenic obesity or metabolic syndrome. Eating behaviors and psychosocial factors should be assessed to improve weight management outcomes. Treatment options for severe pediatric obesity include lifestyle modification, pharmacotherapy, and metabolic and bariatric surgery. Even though progress has been made with regard to the treatment of obesity, safe and effective treatment of severe pediatric obesity is challenging.Discussion and Conclusion: More efforts and innovations are needed to find a solution for the huge medical and emotional burden the children with severe obesity and their families are enduring.