About

Sujin Kim is an Associate Clinical Professor and the Academic Director of the MS in Business Analytics at the Robert H. Smith School of Business at the University of Maryland. She received her Ph.D. in Operations Research from Cornell University. She teaches courses in decision analytics, data analytics, and simulation to MBA and MS students. Her areas of interest include simulation methodology and stochastic simulation-based optimization, with applications in electric power and health service systems. Her work has been published in various academic journals including Mathematics of Operations Research, SIAM Journal on Optimization, ACM Transactions on Modeling and Computer Simulation, Journal of Quality Technology, and Applied Energy.

Research topics

• Endocrinology
• Internal medicine
• Medicine
• Chemistry
• Food science
• Biochemistry
• Biology

Selected publications

• Bone-Specific Alkaline Phosphatase as a Complementary Diagnostic Marker for the Assessment of Children and Adolescents with Secondary Osteoporosis

  Diagnostics · 2025-03-05 · 2 citations

  articleOpen access

  Background/Objective: With increasing cases of osteoporosis in children and adolescents, the need for timely diagnosis, management, and follow-up has become important. This study aimed to determine whether bone turnover markers (BTMs), particularly serum bone-specific alkaline phosphatase (BsALP) and serum C-telopeptide of collagen type 1 (CTx), accurately reflect BMD. Methods: In this retrospective study, 280 post-puberty males and females who were previously diagnosed with hemato-oncologic, rheumatic, gastrointestinal, and endocrinologic diseases at a single tertiary care center were reviewed. The association between the lumbar spine bone mineral density (LSBMD) Z-scores and BTMs, such as BsALP and CTx, were assessed. The LSBMD was measured in the anterior–posterior direction using DXA, and BTMs were determined using the blood samples obtained. Results: Of the 280 patients, 95 were male (33.9%), and the mean age was 15.4 ± 2.07 years. With multivariate regression analysis, LSBMD Z-scores and BsALP showed a negative correlation with p < 0.007, while CTx was not statistically significant. The logistic regression models showed that after adjusting for underlying diseases and sex, as BsALP increased, the probability of LSBMD Z-score being ≤−2 increased with an odds ratio of 1.043 (p = 0.048). When comparing BTMs with vertebral fracture while adjusting for underlying diseases and sex, as BsALP increased, the probability of vertebral fracture increased with an odds ratio of 1.035 (p = 0.005). Conclusions: The positive correlation between BsALP and LSBMD Z-scores being ≤−2, as well as with vertebral fracture after adjusting for underlying diseases and sex, suggests the possible application of BsALP as a predictor of bone health in patients.

  PublisherOA PDFDOI

• SAT-652 Emergency hospitalization of Young-onset Diabetes: Data from the Korean National Health Insurance Service

  Journal of the Endocrine Society · 2025-10-01

  articleOpen access

  Abstract Disclosure: C. won-kyoung: None. B. Eunha: None. S. Sim: None. S. Park: None. S. Kim: None. S. Kim: None. M. Ahn: None. S. Kim: None. K. Cho: None. K. Han: None. M. Jung: None. B. Suh: None. OBJECTIVE To explore the incidence of emergency hospitalization among young-onset diabetes using a nationwide registry database. RESEARCH DESIGN AND METHODS Based on the Korean National Health Insurance Service-National Sample Cohort database from 2006 to 2019, data were collected for patients aged ≤30 years with type 1 (T1D) and type 2 diabetes (T2D). The risks of emergency hospitalization were compared with those in the general population. Results: The study consisted of 512,756 participants. T1D and T2D were detected in 428 and 1,298 participants, respectively. After adjusting for sex, age and family income, the hazard ratios (HRs) of any emergency hospitalization were 4.70 (95% confidence interval [CI], 4.07–5.44) and 3.43 (95% CI, 3.07–3.83) for T1D and T2D, respectively. The HRs of emergency hospitalization due to endocrine problems were 439.53 (95% CI, 341.32–566.00) and 57.06 (95% CI, 36.97–88.06) for T1D and T2D, respectively. The HRs of emergency hospitalization due to cardiovascular problems were 3.67 (95% CI, 1.38–9.80) and 6.02 (95% CI, 3.86–9.38) for T1D and T2D, respectively. The HRs of emergency hospitalization due to infective disorders were 3.48 (95% CI, 2.06–5.87) and 4.72 (95% CI, 3.41–6.53) for T1D and T2D, respectively. The HRs of emergency hospitalization due to cancer were 2.57 (95% CI, 0.36–18.26) and 5.57 (95% CI, 2.63–11.81) for T1D and T2D, respectively. Conclusions: In South Korea, patients with young-onset diabetes are at high risk of emergency hospitalization for various reasons. Presentation: Saturday, July 12, 2025

  PublisherOA PDFDOI

• The association of plasma asprosin with anthropometric and metabolic parameters in Korean children and adolescents

  Frontiers in Endocrinology · 2024-10-03 · 8 citations

  articleOpen access1st author

  Background This study aimed to determine the correlation of plasma asprosin with anthropometric and metabolic parameters in Korean children and adolescents. Methods This single-center study included 109 Korean children and adolescents: 62 (56.9%) obese participants with a body mass index (BMI) ≥95th percentile and 47 (43.1%) healthy controls with BMI between the 15th and 85th percentile. Metabolic parameters were measured, including fasting blood glucose, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), triglyceride and glucose (TyG) index, and lipid profiles. Results Plasma asprosin levels were higher in the obese group than in the control group (mean 87.0 vs. 69.3 ng/mL; p = 0.001) and in the IR group than in the non-IR group (mean 98.6 vs. 70.2 ng/mL; p < 0.001). Plasma asprosin levels were not associated with sex or pubertal stage. Plasma asprosin levels were positively correlated with BMI SDS ( r = 0.34; p = 0.002), glycated hemoglobin (HbA1c) ( r = 0.25; p = 0.02), glucose ( r = 0.33; p = 0.002), insulin ( r = 0.44; p < 0.001), HOMA-IR ( r = 0.47; p < 0.001), triglyceride (TG) ( r = 0.33; p = 0.003), high-density lipoprotein (HDL) cholesterol ( r = -0.29; p = 0.008), and TyG index ( r = 0.38; p < 0.001). Multiple linear regression analysis indicated that plasma asprosin levels were independently associated with HOMA-IR ( p < 0.001) and TG/HDL cholesterol ratio ( p < 0.001). Conclusions This study demonstrated an association between plasma asprosin levels and obesity and insulin resistance in Korean children and adolescents.

  PublisherOA PDFDOI

• Causality between Sex Hormones and Bone Mineral Density in Childhood: Age- and Tanner-Stage-Matched Sex Hormone Level May Be an Early Indicator of Pediatric Bone Fragility

  Biomedicines · 2024-05-25 · 3 citations

  articleOpen access

  This study aimed to investigate the impact of hypogonadism on bone mineral density (BMD) in children and adolescents with chronic diseases to determine the relationship between sex hormones and BMD. This retrospective study included 672 children and adolescents with chronic diseases such as hemato-oncologic, rheumatoid, gastrointestinal, and endocrinologic diseases. The relationship between the sex- and Tanner-stage-matched Z-scores for sex hormones and the sex- and age-matched lumbar spine BMD (LSBMD) Z-scores was evaluated. Adjustments were made for confounders such as underlying diseases, age at diagnosis, and age- and sex-matched body mass index Z-scores. Patients had a mean LSBMD Z-score of −0.55 ± 1.31. In the multivariate regression analysis, male testosterone showed a positive association with the LSBMD Z-score (p < 0.001), whereas female estradiol, luteinizing hormone, and follicular-stimulating hormone showed no significant association with the LSBMD Z-scores. In the male group, the testosterone level was associated with LSBMD Z-scores > −1.0 (p < 0.001), > −2.0 (p < 0.001), and > −3.0 (p = 0.002), while the estradiol level was associated with LSBMD Z-scores > −2.0 (p = 0.001) and > −3.0 (p = 0.002) in the female group. In conclusion, sex hormones are associated with BMD in children and adolescents with chronic diseases. Therefore, various measures may be necessary to predict future skeletal problems and improve bone health in these patients.

  PublisherOA PDFDOI

• The association of serum irisin with anthropometric, metabolic, and bone parameters in obese children and adolescents

  Frontiers in Endocrinology · 2024-01-25 · 14 citations

  articleOpen access1st author

  Background Irisin is an adipomyokine secreted by muscle and adipose cells, and it plays a role in glucose, fat, and bone metabolism. This study aimed to determine the correlation of serum irisin levels with anthropometric, metabolic, and bone parameters in obese children and adolescents. Methods This single-center study included 103 Korean children and adolescents: 54 (52.4%) obese participants with a body mass index (BMI) ≥95th percentile and 49 (47.6%) healthy controls with BMI within the 15th to 85th percentile. Various parameters were measured, including fasting blood glucose, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), triglyceride and glucose (TyG) index, lipid profile, alkaline phosphatase (ALP), osteocalcin, and 25(OH)-Vitamin D levels. Bone mineral density (BMD) was measured using dual-energy X-ray absorptiometry (DEXA) in 33 healthy subjects. Results Serum irisin was significantly higher in the obese group than in the control group (mean 18.1 ± 3.5 vs. 16.2 ± 2.0 ng/mL; p = 0.001). Serum irisin level was positively correlated with chronological age ( r = 0.28; p = 0.004), height SDS ( r = 0.24; p = 0.02), BMI SDS ( r = 0.37; p < 0. 001), fasting glucose ( r = 0.27; p = 0.007), fasting insulin ( r = 0.23; p = 0.03), HOMA-IR ( r = 0.21; p = 0.04), osteocalcin ( r = 0.27; p = 0.006) and negatively correlated with HDL cholesterol ( r = -0.29; p = 0.005). All these correlations were evident in obese subjects but not in healthy subjects. ALP and 25(OH)-Vitamin D were unrelated to irisin levels. Among 33 healthy subjects, total body-less head (TBLH) BMD Z-score was positively correlated with serum irisin ( r = 0.39; p = 0.03), osteocalcin ( r = 0.40; p = 0.02), fasting insulin ( r = 0.39; p = 0.04), and HOMA-IR ( r = 0.38; p = 0.047). Conclusion This study demonstrated an association between irisin levels and glucose, lipid, and bone parameters in children and adolescents. Our findings suggest that irisin has a potential role in metabolic disorders and bone health in obese children and adolescents.

  PublisherOA PDFDOI

• THU138 The Association Between Irisin And Anthropometric And Metabolic Parameters In Obese Children And Adolescents

  Journal of the Endocrine Society · 2023-10-01

  articleOpen access

  Abstract Disclosure: S. Kim: None. S. Kim: None. S. Park: None. S. Sim: None. S. Kim: None. M. Ahn: None. C. Won-kyoung: None. C. Kyoung Soon: None. M. Jung: None. B. Suh: None. Background: Irisin is a myokine secreted from skeletal muscle that plays an important role in the regulation of adipokine secretion and the differentiation of osteoblast and osteoclasts. Irisin has been shown to increase browning of adipose tissue, thermogenesis, energy expenditure, and insulin sensitivity. The aim of this study was to evaluate the relation of serum irisin level with metabolic, anthropometric parameters and bone mineral density in children and adolescents. Methods: This study included 103 Korean children and adolescents in a single center: 49 (47.6 %) obese participants with a body mass index (BMI) ≥95th percentile and 54 (52.4%) healthy control with BMI 15-85th percentile. Fasting serum irisin was quantitatively assayed by ELISA. Lipid profile, fasting blood glucose, fasting insulin, the homeostasis model assessment of insulin resistance (HOMA-IR), Tryglyceride and glucose (TyG) index, osteocalcin and 25-hydroxyvitamin D3 were measured as metabolic parameters. Bone mineral density (BMD) was performed by dual energy X-ray absorptiometry (DXA) in 33 healthy subjects. Results: Serum irsin was significantly higher in obese group than in control group (mean 18.1 ± 3.5 vs 16.2 ± 2.0ng/mL; P = 0.002). There was no significant difference in serum irisin levels between prepubertal and pubertal subjects. In the all participants, irisin level was positively correlated with height SDS (r = 0.24; P = 0.02), BMI SDS (r = 0.37; P <0.001), HOMA-IR(r = 0.21; P = 0.04) and osteocalcin (r = 0.27; P = 0.006). Serum irisin level was negatively correlated with HDL cholesterol (r = -0.29; P = 0.005) and positively correlated with total body less head (TBLH) Z-score (r = 0.40, P = 0.03). Conclusions: This study showed the association between irisin levels with BMI standard deviation score, HOMA-IR and HDL cholesterol. Our data showed a positive correlation between irisin levels and BMD in healthy subjects. Further studies are needed to clarify the mechanisms by which irisin could affect glucose/lipid metabolism and bone metabolism. Presentation: Thursday, June 15, 2023

  PublisherDOI

• Validity and Reliability of a Core Competencies Instrument for Nursing Students

  International Journal of Current Research and Review · 2022-01-01

  articleOpen accessSenior author

  Introduction: One of the basic competencies to become a professional nurse is clinical performance. Therefore, many studies use tools modified and supplemented by Choi to measure the clinical performance of nursing students, but there is no tool to measure the core competencies of nursing students. Aim/Objectives: This methodological study tested the reliability and validity of a self-report instrument measuring the core competencies of nursing students. Internal consistency, reliability, and construct validity were assessed using confirmatory and exploratory factor analysis. Methods: Questionnaire data was collected from 249 nursing students at four universities in J province, South Korea, from August 20 to September 30, 2020. Results: The core competencies showed reliable internal consistency, with a Cronbach’s alpha of 0.90 for the total scale. Factor loadings of the 32 items on seven subscales ranged from 0.53 to 0.88, and three factors explained a total variance of 66.22%. The seven subscales model was validated by confirmatory factor analysis (root mean square residual 0.90). Conclusions: The results demonstrate that the instrument is useful in measuring the core competencies of nursing students.

  PublisherDOI

• A Comparative Study of Antifatigue Effects of Taurine and Vitamin C on Chronic Fatigue Syndrome

  Pharmacology &amp Pharmacy · 2022 · 10 citations

  1st authorCorresponding
  • Chemistry
  • Internal medicine
  • Endocrinology

  Vitamin C and taurine (TR) are well known as active components for fatigue recovery. However, the mechanism of the anti-fatigue effects of vitamin C and TR is still unclear. Our study was designed to evaluate the anti-fatigue activities of vitamin C and TR in an animal test for fatigue and to compare the activities between vitamin C and TR. Materials and Methods: Vitamin C, TR or their combination were orally administrated to mice once daily for 15 days, and then metabolic activities such as blood glucose, triglyceride (TG), lactate, and lactate dehydrogenase (LDH) as well as antioxidant activities such as malondialdehyde (MDA) and superoxide dismutase (SOD) were determined (evaluated) after forced swimming test (FST). Results: Compared with the control group, C100, C200, and T50 showed a tendency to decrease mobility in FST. Moreover, TG (C100, C200, T200), LDH (C200), lactic acid (C100) and MDA (C50, C100, C200) levels were inhibited by vitamin C and TR. Conclusions: These results suggest that vitamin C and TR have anti-fatigue activities in mice, with vitamin C providing a stronger effect.

  PublisherOA PDFDOI

• High Glycated Hemoglobin Instead of High Body Mass Index Might Increase the Urine N-Acetyl-β-D-glucosaminidase Con-Centration in Children and Adolescents with Diabetes Mellitus

  Life · 2022-06-12 · 2 citations

  articleOpen access

  Children with diabetes, and particularly those with obesity, have poor glycemic control. They are thus at higher risk of early microvascular complications. Renal tubulointerstitial markers are integral to evaluating diabetic nephropathy. Various biomarkers have been proposed, but their role in the obese pediatric population is uncertain. We investigated renal injury markers in children with diabetes, according to obesity, and determined their role as early predictors of diabetic nephropathy. Fifty-three children and adolescents, diagnosed with either type 1 or 2 diabetes mellitus, and 43 control children, aged 7–18 years, were included. Clinical and laboratory characteristics, including six renal injury markers, were compared among subjects according to body mass index and presence of diabetes mellitus. Urine neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, and N-acetyl-β-D-glucosaminidase (NAG) showed significant difference between controls and diabetic children, whereas urine NAG was the only biomarker that was significantly lower either in non-obese or obese controls as compared to diabetic children. Urine NGAL, KIM-1, and NAG showed significant correlations with both HbA1c and urine ACR, whereas only urine NAG was significantly correlated with HbA1c even when groups were subdivided based on the presence of either obesity or diabetes. After adjusting for age, sex, body mass index, duration of known diabetes, and urine albumin-to-creatinine ratio, HbA1c remained a significant risk factor for elevated urine NAG. Urine NAG could be a useful indicator of tubulointerstitial damage in children with diabetes in the pre-albuminuric state. Tighter glycemic control appears to be crucial for avoiding early progression to diabetic nephropathy.

  PublisherOA PDFDOI

• Goiter at Diagnosis Might Be Predicting Factor for Early Onset Intractable Graves’ Disease

  Journal of the Endocrine Society · 2021-05-01 · 1 citations

  articleOpen access

  Abstract Introduction: The clinical course of Graves’ disease (GD) treated with anti-thyroid drug (ATD) treatment were reviewed with the aim of establishing criteria able to predict intractable GD. Methods: The clinical course of 116 patients with GD who agreed to participate in this study between March 2009 and August 2019 in the pediatric endocrine clinic at Seoul St. Mary’s and St. Vincent’s Hospitals were reviewed. We defined an intractable as hyperthyroidism persistent over 2 years of ATD or relapsed after ATD withdrawal or had been treated ATD for at least 5 years [1-3]. Result: Of 116 patients diagnosed with GD, 37 patients (31.8%) had remission and 79 (68.2%) had intractable GD. Between intractable and remission GD group, there were no significant difference of female percentage, age at diagnosis, thyroid associated ophthalmopathy, serum levels of triiodothyronine (T3), free tetraiodothyronine (T4), Thyroid stimulating hormone (TSH) and positive rate of thyroid autoantibody (Thyroid peroxidase (TPO), Thyroglobulin (Tg), Thyroid stimulating hormone receptor (TSHR)). In intractable GD patients, the frequency of goiter at diagnosis is higher than remission group (89.9% [71/79] and 70.3% [26/37], P-value = 0.014). In correlation analysis, intractable GD showed positive correlation with goiter (R=0.247, P-value = 0.008). In multivariate logistic analyses, goiter is showed strong relationship with intractable GD (odds ratio, 3.793; 95% confidence interval, 1.367-10.524) after adjusting age and sex. Conclusion: Our study supported that goiter at initial presentation might be predicting factor for early onset intractable GD.

  PublisherOA PDFDOI

Frequent coauthors

• Siba K. Samal

  University of Maryland, College Park

  130 shared

• Anandan Paldurai

  University of Maryland, College Park

  49 shared

• Sa Xiao

  Northwest A&F University

  48 shared

• Moon Bae Ahn

  Catholic University of Korea

  35 shared

• Byung‐Kyu Suh

  Catholic University of Korea

  29 shared

• Peter L. Collins

  Guy's and St Thomas' NHS Foundation Trust

  27 shared

• Min Ho Jung

  Catholic University of Korea

  26 shared

• Cheng‐I Wei

  University of Maryland, College Park

  24 shared