Prevalence and trends in obesity and severe obesity in Korean children and adolescents, 2007-2020: A population-based study.

BACKGROUND: The age-adjusted prevalence of child and adolescent obesity has been stabilized in the Korean population, although severe obesity has increased with adverse health effects. In this study, we detailed the prevalence of and trends in overweight, obesity, and severe obesity in Korean children and adolescents by age group and sex from a nationally representative sample, using a new, 2017 age- and sex-specific reference for body mass index. METHODS: We collected Korea National Health and Nutrition Examination Survey data from the years 2007-2020. A total of 23,595 subjects (11,210 females) aged 2-18 years were included in this study. We calculated the recent prevalence of overweight and obesity, including severe obesity, by weighted data from 2019 and 2020. RESULTS: The prevalence of overweight and obesity (class II and class III obesity) was 23.5% and 14.2% (2.5% and 0.5%), respectively. Males showed a higher prevalence of overweight and obesity. Adolescents aged 13-15 years showed the highest prevalence of severe obesity. A positive linear trend was significant for overweight (p = 0.025), class I obesity (p < 0.001), and class II obesity (p = 0.002) for both sexes and all ages combined. However, the trend of obesity prevalence was different in each subgroup. Comparing pre- and post- COVID-19 pandemic, obesity prevalence seemed to increase, but not significantly. CONCLUSIONS: Despite previous reports that obesity in children and adolescents has remained stable, we found that the prevalence of overweight, obesity, and severe obesity has increased in Korean children and adolescents. The effects of COVID-19 on this trend require further evaluation.

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.

Height outcomes in Korean children with idiopathic short stature receiving growth hormone treatment.

Objectives: Growth hormone (GH) therapy's capacity to increase height velocity and height at the end of the study in children with idiopathic short stature (ISS) is controversial. We aimed to investigate the height standard deviation score (SDS) and height velocity of patients with ISS in Korea who received GH treatment. Methods: We retrospectively reviewed and performed linear mixed model and survival analyses on data from 12 tertiary hospitals in Korea, including subjects diagnosed with ISS from January 2009 to September 2019, treated with GH therapy for more than 6 months, and who were at a pre-pubertal state at the time of diagnosis. Results: We included 578 children (330 boys and 248 girls). The mean daily dose of GH in this study was 0.051 mg/kg, which was lower than the approved dose in Korea of 0.062 - 0.067 mg/kg. Height SDS was higher in patients who started treatment before the age of 6 years. The probability of reaching the target SDS (-1 SDS) from the beginning of treatment to 2-3 years after its start was higher in children starting treatment before the age of 6 years. The hazard ratio to reach the target SDS (-1 SDS) when using automatic pen or electronic devices was 1.727 times higher than that when using the needle and syringe device. Conclusion: ISS patients should start GH treatment at an early age, and even lower-than-recommended drug doses may be effective. The selection of automatic pen or electronic device can have a positive effect on reaching the target height SDS.

Prevalence Trends of Metabolic Syndrome among Korean Children and Adolescents from a Population-Based Cross-Sectional Survey.

The prevalence of metabolic syndrome (MetS) is increasing worldwide. This study aimed to investigate the prevalence trend of metabolic syndrome among Korean adolescents and to examine the effect of changes in dietary components on metabolic syndrome components. It has used the data of children and adolescents (8718 subjects aged 10−18) from the National Health and Nutrition Survey IV-VII (KNHANES 2007−2018) to estimate the recent prevalence of MetS and identify related nutritional factors. The definition of MetS used modified NCEP-ATP III and IDF criteria. The prevalence of MetS among Korean adolescents in 2007−2018 was 4.6% using the modified NCEP-ATP III criteria, and the trend of MetS increased significantly (p trend = 0.02). In the overweight and obese groups, the risk of MetS increased 7.08 (95% CI, 5.19−9.79) and 27.13 (95% CI, 20.90−35.24) compared to the normal-weight group. During KNHANES IV-VII, overall caloric intake increased, carbohydrate and sodium intake decreased, but fat intake increased (KNHANE-IV; 21.3% to VII; 24.0%, p < 0.001). These fat intakes were significantly correlated with an increase in systolic blood pressure, fasting blood glucose, and waist circumference. The prevalence of MetS is also increasing in Korean adolescents, and changes in dietary habits are related. In the future, it is also necessary to study the relationship of MetS to lifestyle.

The association between C-reactive protein, metabolic syndrome, and prediabetes in Korean children and adolescents.

PURPOSE: Metabolic syndrome (MetS) is a state of chronic inflammation, and high-sensitivity C-reactive protein (hsCRP) indicates inflammation. This paper evaluates the associations between hsCRP and MetS and its components in Korean children and adolescents. METHODS: We analyzed the data of 1,247 subjects (633 males, 14.2±2.7 years) from the Korea National Health and Nutrition Examination Survey 2016-2017. This study defined MetS and its components using the modified National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) criteria. RESULTS: The mean hsCRP level was 0.86±1.57 mg/dL (median and interquartile range: 0.37 and 0.43 mg/dL). Subjects with MetS had higher hsCRP level than subjects without MetS (geometric mean: 1.08 mg/dL vs. 0.46 mg/dL, p<0.001). With a higher quartile value of hsCRP, the prevalence of MetS increased. Compared to the lowest quartile, the odds ratio (OR) for MetS in the highest quartile was 7.34 (3.07-17.55) after adjusting for age and sex. In the top quartile of hsCRP, the risk of abdominal obesity and low HDL was high after adjusting for age, sex, and other components of MetS. Additionally, the OR for prediabetes (HbA1c ≥5.7%) in the highest quartile was 2.70. CONCLUSION: Serum hsCRP level was positively associated with MetS and prediabetes using NCEP-ATP III criteria. Among the MetS components, abdominal obesity and low HDL were highly correlated with hsCRP in Korean children and adolescents.

Clinical practice guidelines for optimizing bone health in Korean children and adolescents.

The Committee on Pediatric Bone Health of the Korean Society of Pediatric Endocrinology has newly developed evidence-based clinical practice guidelines for optimizing bone health in Korean children and adolescents. These guidelines present recommendations based on the Grading of Recommendations, which includes the quality of evidence. In the absence of sufficient evidence, conclusions were based on expert opinion. These guidelines include processes of bone acquisition, definition, and evaluation of low bone mineral density (BMD), causes of osteoporosis, methods for optimizing bone health, and pharmacological treatments for enhancing BMD in children and adolescents. While these guidelines provide current evidence-based recommendations, further research is required to strengthen these guidelines.

Trends of Diabetes and Prediabetes Prevalence among Korean Adolescents From 2007 to 2018.

BACKGROUND: To provide updated prevalence data and to estimate changes in the prevalence of diabetes among Korean adolescents by sex and age between 2007 and 2018. METHODS: We used the data of children and adolescents (8,718 subjects aged 10 to 18 years) from the Korea National Health and Nutrition Examination Survey IV-VII (KNHANES 2007-2018). The recent prevalence of diabetes and pre-diabetes was estimated by using the latest KNHANES VII. The linear trends were estimated by comparing 3-year KNHANES cycles according to sex and by using logistic regression. RESULTS: The prevalence of diabetes and pre-diabetes was 0.298% (95% confidence interval [CI], 0.289-0.308) and 7.914% (95% CI, 0.43-0.49). The prevalence of diabetes significantly increased from 0.189 to 0.430 during KNHANE IV and VII. A positive linear trend is significant for diabetes (P trends = 0.006) in only male subjects. The prevalence of pre-diabetes significantly increased from 5.86 to 12.08 in both sexes. During KNHANES IV and VII, the prevalence of obesity increased significantly. CONCLUSION: Between 2007 and 2018, the prevalence of diabetes among Korean adolescents increased. Further studies are required to determine the causes of these increases.

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.

Early menarche and its consequence in Korean female: reducing fructose intake could be one solution.

The mean age at menarche (AAM) of Korean females has been rapidly decreasing over the last 50 years; currently, the prevalence of early menarche (<12 years) is 22.3%. Female adolescents who experience early menarche are known to be at greater risk of psychosocial and behavioral problems along with several physical health problems such as menstrual problems. They also tend to achieve a shorter final height and develop obesity. Population-based Korean studies have shown a strong association between early menarche and the risk of obesity, insulin resistance, metabolic syndrome, nonalcoholic fatty liver disease, diabetes, breast cancer, and cardiovascular disease in adulthood. Although the exact mechanism of how early menarche causes cardiometabolic derangement in later adulthood is unknown, childhood obesity and insulin resistance might be major contributors. Recent studies demonstrated that an excessive consumption of fructose might underlie the development of obesity and insulin resistance along with an earlier AAM. A positive association was observed between sugar-sweetened beverages (a major source of fructose) intake and obesity, metabolic syndrome, insulin resistance, and cardiometabolic risk in Korean females. In pediatrics, establishing risk factors is important in preventing disease in later life. In this regard, early menarche is a simple and good marker for the management of cardiometabolic diseases in adulthood. Decreasing one's fructose intake might prevent early menarche as well as the development of obesity, insulin resistance, and cardiometabolic diseases.

Low Bone Mineral Density at Initial Diagnosis in Children and Adolescents with Graves' Disease.

Previous studies have reported reduced bone mineral density (BMD) in patients with hyperthyroidism. We assessed the association of BMD in children and adolescents with Graves' disease (GD) after correcting for potential confounders affecting BMD such as age, sex, and pubertal status. Forty-four children and adolescents with GD and 172 age- and sex-matched healthy controls were enrolled in this study. We analyzed auxological features, BMD, and levels of thyroid hormone, thyroid-stimulating hormone, and thyroid autoantibodies. We measured BMD by dual-energy X-ray absorptiometry at the time of diagnosis in all patients. The mean age of all patients with GD (9 boys and 32 girls) was 12.1 ± 2.2 years (range, 7.0-16.0). Their initial mean free T4 and thyroid-stimulating hormone levels were 3.51 ± 1.56 ng/dL and 0.04 ± 0.03 IU/L, respectively. The mean BMD Z-scores of the lumbar spine (LS), femoral neck, and total body less head of patients with GD were significantly lower than those of control subjects. Eleven patients (26.8%) had low bone density (LS BMD Z-scores < -2.0). To identify correlations of patient characteristics with BMD Z-scores at each site, alkaline phosphatase had a significant negative correlation with BMD Z-scores at LS and femoral neck, but not total body less head (r = -0.441; p = 0.004 and r = -0.351; p = 0.025, respectively). Children and adolescents with newly diagnosed GD had lower bone mass than their healthy peers. These results suggest that BMD measurement at initial evaluation may be necessary in this population.

2017 Clinical practice guidelines for dyslipidemia of Korean children and adolescents.

The Committee on Dyslipidemia of Korean Pediatric and Adolescents of the Korean Society of Pediatric Endocrinology has newly developed evidence-based clinical practice guidelines for dyslipidemia in Korean children and adolescents. These guidelines were formulated with the Grading of Recommendations, which include both the strength of recommendations and the quality of evidence. In the absence of sufficient evidence, conclusions were based on expert opinion. These guidelines are based on the 2011 National Heart, Lung, and Blood Institute Guidelines, which focus on the prevention of cardiovascular disease in children and draw from a comprehensive review of evidence. These guidelines contain the definition of and screening process for dyslipidemia and introduce new dietary methods: the Cardiovascular Health Integrated Lifestyle Diet (CHILD)-1, the CHILD-2-low-density lipoprotein cholesterol, and the CHILD-2-triglyceride. Potential drug therapies for dyslipidemia along with their main effects and doses were also included.

2017 Clinical practice guidelines for dyslipidemia of Korean children and adolescents

The Committee on Dyslipidemia of Korean Pediatric and Adolescents of the Korean Society of Pediatric Endocrinology has newly developed evidence-based clinical practice guidelines for dyslipidemia in Korean children and adolescents. These guidelines were formulated with the Grading of Recommendations, which include both the strength of recommendations and the quality of evidence. In the absence of sufficient evidence, conclusions were based on expert opinion. These guidelines are based on the 2011 National Heart, Lung, and Blood Institute Guidelines, which focus on the prevention of cardiovascular disease in children and draw from a comprehensive review of evidence. These guidelines contain the definition of and screening process for dyslipidemia and introduce new dietary methods: the Cardiovascular Health Integrated Lifestyle Diet (CHILD)-1, the CHILD-2-low-density lipoprotein cholesterol, and the CHILD-2-triglyceride. Potential drug therapies for dyslipidemia along with their main effects and doses were also included.

Serum uric acid in Korean children and adolescents: reference percentiles and association with metabolic syndrome.

PURPOSE: To establish age/sex-specific reference intervals for serum uric acid and to examine the associations between serum uric acid level and metabolic syndrome (MetS) and its components in Korean children and adolescents. METHODS: We analyzed data for 1,349 subjects aged 10 to 19 years from the Korea National Health and Nutrition Examination Survey 2016-2017. RESULTS: The mean uric acid levels were 5.9±1.3 mg/dL (interquartile range, 5.0-6.8 mg/dL) in males and 4.6±0.9 mg/dL (interquartile range, 3.9-5.2 mg/dL) in females. The mean uric acid level increased significantly from 10-13 years of age in males, but not in females. The overall prevalence of MetS was 5.9% (7.3% in males and 4.3% in females; P=0.022). The prevalences of MetS in the lowest, second, third, and highest quartiles of uric acid level were 4.4%, 3.3%, 6.1%, and 15.2%, respectively, in males (P for trend <0.001) and 1.9%, 0.0%, 4.1%, and 10.9%, respectively, in females (P for trend <0.001). Compared with the lowest quartile of uric acid level, the odds ratio (with 95% confidence interval) for MetS in the highest quartile was 2.897 (1.140-7.361) in males and 5.173 (1.459-18.342) in females. Subjects in the highest quartile exhibited increased risk for abdominal obesity and low high-density lipoprotein cholesterol in both sexes. CONCLUSION: Serum uric acid level is positively associated with MetS and its components abdominal obesity and low high-density lipoprotein cholesterol.

Growth status of children and adolescents born small for gestational age at full term in Korea: data from the KNHANES-V.

Objectives Small for gestational age (SGA) status is known to show stunted growth and results in short stature in adults. The aim of this study was to describe the current short stature in subjects born SGA in Korea and to assess catch-up growth (CUG) or non-CUG. Methods We analyzed data from 3,524 subjects (1,831 male) aged 1-18 years who were born as full-term singletons and who participated in the Fifth Korean National Health and Nutrition Examination Survey (2010-2011). Results The prevalence of SGA was 13.4% (n=471). Subjects born SGA had fathers with shorter height, shorter mother's height, and mid-parental height than non-SGA subjects (p<0.05 for all). The odds ratios (ORs) for SGA birth of a short statured father and a short statured mother were 2.00 (95% CI; 1.15-3.47) and 2.11 (95% CI; 1.30-3.40), respectively. Among 471 SGA subjects, 28 subjects (5.9%) were non-CUG, which made up 36.4% of all subjects with short stature. The CUG subjects had a higher father's height, mother's height, mid-parental height, and current BMI (p<0.05 for all). The non-CUG subjects had a higher percentage of fathers being near-short stature (height<10th percentile; 33.3 vs. 12.7%; p=0.008) and mothers being near-short stature (39.3 vs. 13.9%; p<0.001). Conclusion Korean subjects born SGA had a higher risk of current short stature. This population-based nationwide survey also showed that both father's and mother's short stature are risk factors of not only SGA birth but also non-CUG in their children.

Influenza Vaccine Effectiveness among Elementary School Students in Korea during the 2016-2017 Seasons: a Cross-Sectional Survey.

BACKGROUND: Annual vaccination is the principal way to reduce the mortality and morbidity associated with influenza. In the 2016-2017 influenza seasons, the influenza epidemic appeared to exhibit a different pattern from the previous years. Because of the unusual trend, the incidence of influenza-like patients among school-aged children had increased, causing doubts about the effectiveness of the influenza vaccine. Therefore, this study aimed to evaluate the effectiveness of the influenza vaccine among elementary school students in Korea. METHODS: The study was conducted in elementary schools in each province of Korea in cooperation with the Student Health Policy Division of the Ministry of Education. Each Provincial Office of Education of Korea, except for Jeju, randomly selected one to two elementary schools for each District Office of Education. A total of 2,739 elementary school students were enrolled and vaccination and influenza infection status were collected from the subjects' parents through questionnaires, from February 13th to 21st in 2017. Vaccine effectiveness was defined as calculating the infection rate of influenza among the vaccinated and unvaccinated groups and determining the decreased infection rate of the vaccinated group relative to the unvaccinated group, while adjusting for time of vaccination and infection. RESULTS: Adjusting for the interval between vaccination and infection, vaccine effectiveness of influenza was 17.6% (95% confidence interval [CI], 4.6% to 28.9%), 22.5% (95% CI, 10.3% to 33%), and 28.7% (95% CI, 17.5% to 38.3%) at 2 or more weeks, 3 or more weeks, and 4 or more weeks after vaccination, respectively. CONCLUSION: In conclusion, considering the time required for adequate immunogenicity, the 2016-2017 seasonal influenza vaccine effectiveness in Korean elementary school students was 17.6%-28.7%, which was less effective than that of previous years.

2017 Clinical practice guidelines for dyslipidemia of Korean children and adolescents.

The Committee on Dyslipidemia of Korean Pediatric and Adolescents of the Korean Society of Pediatric Endocrinology has newly developed evidence-based clinical practice guidelines for dyslipidemia in Korean children and adolescents. These guidelines were formulated with the Grading of Recommendations, which include both the strength of recommendations and the quality of evidence. In the absence of sufficient evidence, conclusions were based on expert opinion. These guidelines are based on the 2011 National Heart, Lung, and Blood Institute Guidelines, which focus on the prevention of cardiovascular disease in children and draw from a comprehensive review of evidence. These guidelines contain the definition of and screening process for dyslipidemia and introduce new dietary methods: the Cardiovascular Health Integrated Lifestyle Diet (CHILD)-1, the CHILD-2-low-density lipoprotein cholesterol, and the CHILD-2-triglyceride. Potential drug therapies for dyslipidemia along with their main effects and doses were also included.

A Case of Autosomal Dominant Osteopetrosis Type 2 with a CLCN7 Gene Mutation

Osteopetrosis is a rare genetic disease characterized by increased bone density and bone fractures due to defective osteoclast function. Autosomal dominant osteopetrosis type 2 (ADO-2), Albers-Schonberg disease, is characterized by the sclerosis of bones, predominantly involving the spine, pelvis and the base of the skull. Here, we report a typical case of osteopetrosis in a 17.7-year-old male who carries a heterozygous c.746C>T mutation in exon 9 in the chloride voltage-gated channel 7 (CLCN7) gene. The patient's spine showed multiple sclerotic changes including sandwich vertebra. His father had the same mutation but his skeletal radiographs were normal. This is the first reported case of ADO-2, confirmed by genetic testing in a Korean patient.

Early Menarche is a Risk Factor for Short Stature in Young Korean Females: An Epidemiologic Study

Objective: To assess the association between age at menarche and adult height [and body mass index (BMI)] in young Korean females and also to investigate whether early menarche (<12 years) is a risk factor for short stature and obesity in young Korean females. Methods: Data on 1148 females aged 18-30 years and 612 mother (612 pairs of mothers and daughters) from the 6th Korea National Health and Nutrition Examination Survey (2013-2015) were analyzed. Results: Among 1148 females, 256 (22.3%) had early menarche. Their stature was approximately 0.445 cm shorter when menarche had occurred one year earlier. The prevalence of short stature (≤153 cm) and obesity (BMI ≥25) was higher in females with early menarche compared to those with later menarche (short stature: 10.5% vs 6.4%, obesity; 20.7% vs 13.1%, all p<0.001). In multivariate regression, the odds ratio (OR) for short stature was 2.62 [95% confidence interval (CI): 1.26-5.44] after adjusting for current age and mother's height. OR for obesity was 1.74 (95% CI: 0.98-3.07) after adjusting for age and maternal BMI. Conclusion: Final height in girls is influenced by age of menarche. Early menarche increased the risk for adult short stature in young Korean females.

Korean reference for full-term birth length by sex: data from the 4th Korean National Health and Nutrition Examination Survey (KNHANES-IV; 2007-2009).

PURPOSE: The purpose of this study was to construct reference data for birth length of full-term and preterm Korean infants by sex and to define a sex-specific birth length cut-off to identify small for gestational age (SGA). METHODS: Data were collected from the 4th Korean National Health and Nutrition Examination Survey (2007-2009), comprising 843 children with birth length data and birth history. RESULTS: References for the 3rd, 10th, 25th, 50th, 75th, 90th, and 97th percentiles of birth length and weight were created using singleton neonates of gestational age (GA) 36-37 weeks and 38-41 weeks by sex. The birth length cutoff value for SGA (<10th percentile) was 48 cm in both male and female neonates, and the ≤3rd percentile cutoff was 47 cm in males and 46 cm in females born at a GA of 38-41 weeks. CONCLUSION: New Korean reference data were created for birth length and differed from those of other ethnicities. Further research on short-term and long-term health outcomes of SGA infants based on the new reference data is needed.

Ease of Use, Preference, and Safety of the Recombinant Human Growth Hormone Disposable Pen Compared with the Reusable Device: A Multicenter, Single-Arm, Open-Label, Switch-Over, Prospective, Phase IV Trial.

PURPOSE: To assess the usability and safety of the disposable pen compared to those of reusable devices in patients receiving recombinant human growth hormone (rhGH) treatment. PATIENTS AND METHODS: This study was a multicenter, single-arm, open-label, switch-over, prospective, Phase IV trial. After screening, eligible patients who were previously treated with rhGH using a reusable device were enrolled to receive treatment with the disposable pen for 8 weeks. The ease of use, preference, and tolerability of the disposable pen compared to those of the reusable device were assessed by the subjects and/or their caregivers using a questionnaire. Adverse events were evaluated by the investigators. RESULTS: Of 116 subjects enrolled in this study, 115 received treatment with the disposable pen and 109 completed the study. The mean age of the subjects was 9.4 years. Compared to the previous reusable device, the disposable pen was assessed as significantly easier to use (mean value 7.88, 95% confidence interval (CI) [7.45-8.30] on a numerical scale ranging from 0 (far less easy) to 10 (far easier)). Furthermore, the percentage of subjects who preferred the disposable pen to the previously used reusable device was 75.7% (95% CI [67.6%-83.8%]). The percentages of subjects who rated pain and discomfort at the injection site as "not at all" were higher after using the disposable pen compared to the reusable device. No specific safety concerns were identified. CONCLUSION: The disposable pen is easier to use than the reusable devices and is preferred by approximately 75% of patients receiving rhGH treatment. Moreover, the disposable pen is safe and acceptable. Therefore, it could be a good alternative to reusable devices. The disposable pen is expected to provide benefits to patients receiving rhGH treatment. CLINICALTRIALSGOV IDENTIFIER: NCT03015909.