Infant born small for gestational age (SGA) are at increased risk of perinatal morbidity, persistent short stature and metabolic alterations in later life. The result of SGA followed by rapid weight gain during early postnatal life has been associated with increased long-term risks for central obesity, insulin resistance, impaired glucose tolerance, type 2 diabetes, hypertension, increased fat mass, and cardiovascular disease. We should carefully monitor their weight during infancy and childhood to prevent excessive rates of weight gain. 'Healthy catch up growth' may decreased the risk of obesity-related comorbidities in SGA. Establishing the optimal growth patterns in SGA to minimize short- and long-term risks is important, and further studies will be needed. This review discusses recent studies concentrating on obesity-related morbidities in SGA infants that may provide insight into growth monitoring.

Sochung Chung. JOMES 2017;26:243-50. https://doi.org/10.7570/jomes.2017.26.4.243

Childhood obesity prevalence has been increased and known to be related to various diseases and mortality in adult and body mass index (BMI) has been widely used as a screening tool in children with obesity. It is important to understand what BMI is and its limitations. BMI is a measure of weight adjusted for height. Weight scales to height with a power of about 2, is the basis of BMI (weight/height(2)) as the scaling of body weight to height across adults provides powers rounded to 2. BMI has the advantage of a simple and noninvasive surrogate measure of body fat, but it has limitation in differentiating body fat from lean (fat free) mass and low-moderate sensitivity is problematic for clinical applications. Among overweight children higher BMI levels can be a result of increased either fat or fat-free mass. BMI could be divided into fat-free mass index and fat mass index. Monitoring of the changes in body composition is important as distinguishing changes in each component occur with rapid growth in adolescents as it is occur in concert with changes in the hormonal environment. Reference values for each body composition indexes and chart created with selected percentiles of a normal adolescent population could be helpful in growth assessment and health risk evaluation.

Park HW, et al. J Korean Med Sci. 2015 Dec;30(12):1828-1835. http://dx.doi.org/10.3346/jkms.2015.30.12.1828

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.

Kim H, et al. Nutr Res Pract. 2011 Jun;5(3):246-252. http://dx.doi.org/10.4162/nrp.2011.5.3.246