Osong Public Health and Research Perspectives

Han Byul Jang

4 Articles

Associations Between Estimated Desaturase Activity and Insulin Resistance in Korean Boys: Young Sim Choi, Han Byul Jang, Ju Yeon Park, Hye-Ja Lee, Jae-Heon Kang, Kyung-Hee Park, Jong Ho Lee, Sang Ick Park, Jihyun Song; Osong Public Health Res Perspect. 2014;5(5):251-257. Published online October 31, 2014; DOI: https://doi.org/10.1016/j.phrp.2014.08.008

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Abstract PDF: Objectives
Obesity in childhood increases the risk of obesity in adulthood, and is predictive of the development of metabolic disorders. The fatty acid compositions of various tissues, including blood, are associated with obesity and obesity-associated disorders. Thus, tracking plasma phospholipid (PL) features and metabolic parameters in young individuals may strengthen the utility of fatty acid composition as an early biomarker of future metabolic disorders.
Methods
Anthropometric and blood biochemical data were obtained from 131 Korean males aged 10.5 ± 0.4 years, and followed up at 2 years. We analyzed the plasma PL fatty acids according to obesity. Obese children were defined as those with a body mass index (BMI) greater than the 85^th percentile for age and gender, based on Korean child growth standards.
Results
Activities of lipid desaturases, stearyl-CoAD (SCD-16,16:1n-7/16:0), delta-6D (D6D, 20:3n-6/18:2n-6), and delta-5D (D5D, 20:4n-6/20:3n-6), were estimated. Obese individuals had significantly higher proportions of palmitoleic acid (16:1n-7) and dihomo-gamma linolenic acid (DGLA, 20:3n-6) at both baseline and follow-up than did lean individuals. The activities of SCD-16 and D6D were higher in obese than lean boys. The baseline SCD-16 activity level was positively associated with the baseline waist circumference (WC) and the metabolic risk score. The baseline D6D level was positively associated with WC and also with the homeostasis model of assessment of insulin resistance (HOMA-IR), a surrogate marker of insulin resistance (IR), and metabolic risk score at both baseline and follow-up.
Conclusion
In young Korean males, higher D6D activity predicts the future development of IR and associated metabolic disorders including dyslipidemia.

Relationship between Serum Levels of Body Iron Parameters and Insulin Resistance and Metabolic Syndrome in Korean Children: Hye-Ja Lee, Han Byul Jang, Ji Eun Park, Kyung-Hee Park, Jae Heon Kang, Sang Ick Park, Jihyun Song; Osong Public Health Res Perspect. 2014;5(4):204-210. Published online August 31, 2014; DOI: https://doi.org/10.1016/j.phrp.2014.06.005

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Abstract PDF: Objectives
An increase in serum ferritin and levels of the cleaved soluble form of transferrin receptor (sTfR) are related to several metabolic conditions. We evaluated the relationship between body iron status indicators, including ferritin and sTfR, and insulin resistance and metabolic syndrome (MetS) in Korean children.
Methods
A cross-sectional study was conducted on 1350 children in Korea. Anthropometrical parameters; lipid profiles; levels of glucose, insulin, and leptin; and iron status indicators, including sTfR, serum ferritin, serum iron, total iron-binding capacity (TIBC), and transferrin saturation (TS), were analyzed.
Results
Although serum sTfR levels were significantly higher in boys than in girls (2.20 vs. 2.06 mg/L, p < 0.0001), serum iron and TS were higher in girls than in boys (101.38 vs. 95.77 mg/L, p = 0.027 and 30.15 vs. 28.91%, p = 0.04, respectively). Waist circumference (WC) and leptin were most significantly associated with body iron indicators when adjusted for age and sex. After adjusting for age, sex, and WC, sTfR levels showed the strongest positive association with leptin levels (p = 0.0001). Children in the highest tertile for homeostasis model assessment-insulin resistance (HOMA-IR) had higher TIBC (p = 0.0005) and lower serum iron (p = 0.0341), and the lowest TS (p < 0.0001) after adjustment for confounders. Children with higher sTfR were most significantly associated with risk of MetS compared with those lower sTfR (p = 0.0077).
Conclusion
The associations of serum levels of iron metabolism markers with leptin levels, HOMA-IR, and MetS suggest that iron-related factors may involve insulin resistance and MetS.

Association Between Serum Vitamin D and Metabolic Risk Factors in Korean Schoolgirls: Han Byul Jang, Hye-Ja Lee, Ju Yeon Park, Jae-Heon Kang, Jihyun Song; Osong Public Health Res Perspect. 2013;4(4):179-186. Published online August 31, 2013; DOI: https://doi.org/10.1016/j.phrp.2013.06.004

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Abstract PDF: Objectives
Vitamin D, a key regulator of bone metabolism, has been recently been linked with energy homeostasis and metabolic disorders in western countries. However, few studies have focused on the association of vitamin D with metabolic risk factors among Asian children. We studied the prevalence of vitamin D insufficiency and the association of 25-hydroxyvitamin D [25(OH)D] with metabolic risk factors in Korean schoolgirls.
Methods
The sample consisted of 320 13-year-old girls recruited from two middle schools in the city of Gwacheon, Korea (latitude 37°N), in July 2011. Anthropometric and blood biochemistry data were obtained for this cross-sectional observational study. We also obtained lifestyle data from questionnaires and dietary data from 3-day food diaries.
Results
Vitamin D deficiency [25(OH)D < 20 ng/mL] was noted in 63.8% of participants. The mean 25(OH)D level was not significantly lower in the overweight group. Level of physical activity and vitamin D intake did not significantly affect 25(OH)D. However, 25(OH)D levels were positively correlated with milk intake and negatively correlated with soft drink intake. Serum 25(OH)D had a negative relationship with fasting glucose and insulin resistance index (homeostasis model assessment-insulin resistance; HOMA-IR) after adjustment for physical activity and body mass index z score (r = −0.144, p = 0.015), and with metabolic risk score similarly (r = −0.141, p = 0.012). Levels of insulin, HOMA-IR, and systolic blood pressure were higher in girls with deficient 25(OH)D levels than in those with sufficient levels.
Conclusion
We found that low 25(OH)D levels were associated with higher blood glucose and insulin resistance. Korean girls with low 25(OH)D levels could be at increased risk for metabolic disorders.

The Influence of Dietary Patterns on the Nutritional Profile in a Korean Child Cohort Study: Hyeon-Jeong Choi, Hyojee Joung, Hye-Ja Lee, Han Byul Jang, Jae-Heon Kang, Jihyun Song; Osong Public Health Res Perspect. 2011;2(1):59-64. Published online June 30, 2011; DOI: https://doi.org/10.1016/j.phrp.2011.04.007

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Abstract PDF: Objectives
The aim of the present study was to identify the major dietary patterns of seven- and eight-year-old Korean children and to examine the relationship between dietary patterns and obesity, nutrient intake, and diet quality.
Methods
The subjects were 284 seven- and eight-year-old children who participated in the Gwacheon child cohort study. Three dietary patterns emerged from the factor analysis: Korean, modified Western, and Western. Cluster analysis was used to classify the subjects into two dietary groups: Korean and Western diet patterns.
Results
The two different dietary patterns were closely related to dietary quality which in turn was related to health risks. The Western diet group had a lower fiber intake, a higher intake of energy, fat and calcium and a higher dietary diversity score (DDS) than the Korean diet group. The number of days when fruit, milk and dairy products were omitted from the diet was higher for the Korean diet group than for the Western group.
Conclusions
Dietary patterns and related diet quality should be considered when designing nutrition policy and intervention programs for children.

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