Ki Hyun Baek

Catholic University of Korea, Sŏul, Seoul, South Korea

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Publications (49)117.77 Total impact

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    ABSTRACT: The bone loss during the first year was − 0.9% in the lumbar spine and − 1.3% in the femoral neck.•Bone loss during the early postoperative period was more evident in postmenopausal women.•Bone loss was greater in the early postoperative group than in the late postoperative group.•TSH-suppressive thyroid hormone therapy accelerates bone loss, predominantly in postmenopausal women and exclusively during the early post-thyroidectomy period.•We recommend screening postmenopausal women at the start of TSH-suppressive therapy and initiating calcium and vitamin D supplementation.
    Bone 02/2015; 71. DOI:10.1016/j.bone.2014.10.009 · 4.46 Impact Factor
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    ABSTRACT: Objective This study aimed to assess insulin resistance according to maternal age at childbirth.Patients and methodsThe data used in this study were obtained from the 2010 Korean National Health and Nutrition Examination Survey. The present study included a total of 2,233 non-diabetic female subjects ≥ 30 years of age that were subdivided into groups according to their obesity and abdominal obesity (AOB) statuses. The homeostasis model assessment of insulin resistance (HOMA-IR) was used to quantify the insulin resistance according to age at first childbirth and last childbirth.ResultsAge at first childbirth showed a negative relationship with HOMA-IR in both the non-obese and non-AOB groups, while age at last childbirth showed a positive relationship with HOMA-IR in both the non-obese and non-AOB groups. A multivariate logistic regression analysis revealed that age at first and last childbirth were significantly associated with the highest HOMA-IR quartile. The odds ratio was 0.9 [95% confidence interval: 0.82–0.98] for age at first childbirth, and 1.07 [95% confidence interval: 1.01–1.14] for age at last childbirth in the non-obese and non-AOB groups.Conclusion In conclusion, the present study suggests that insulin resistance is increased in females who experienced their first childbirth at a younger age or their last childbirth at a later age, particularly in non-obese individuals. Because these data suggest that childbearing age could be an independent risk factor for diabetes, a high-quality prospective study assessing the relationship between childbearing age and insulin resistance should be performed.This article is protected by copyright. All rights reserved.
    Clinical Endocrinology 01/2015; DOI:10.1111/cen.12712 · 3.35 Impact Factor
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    ABSTRACT: Background. The measurement of stimulated thyroglobulin (sTg) after total thyroidectomy and remnant radioactive iodine (RAI) ablation is the gold standard for monitoring disease status in patients with papillary thyroid carcinomas (PTCs). The aim of this study was to determine whether sTg measurement during follow-up can be avoided in intermediate- and high-risk PTC patients. Methods. A total of 346 patients with PTCs with an intermediate or high risk of recurrence were analysed. All of the patients underwent total thyroidectomy as well as remnant RAI ablation and sTg measurements. Preoperative and postoperative parameters were included in the analysis. Results. Among the preoperative parameters, age below 45 years and preoperative Tg above 19.4 ng/mL were significant risk factors for predicting detectable sTg during follow-up. Among the postoperative parameters, thyroid capsular invasion, lymph node metastasis, and ablative Tg above 2.9 ng/mL were independently correlated with a detectable sTg range. The combination of ablative Tg less than 2.9 ng/mL with pre- and postoperative independent risk factors for detectable sTg increased the negative predictive value for detectable sTg up to 98.5%. Conclusions. Based on pre- and postoperative parameters, a substantial proportion of patients with PTCs in the intermediate- and high-risk classes could avoid aggressive follow-up measures.
    International Journal of Endocrinology 01/2015; 2015:1-7. DOI:10.1155/2015/318916 · 1.52 Impact Factor
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    ABSTRACT: The present study evaluated the efficacy of a combination of ibandronate and cholecalciferol on the restoration of the levels of 25-hydroxyvitamin D (25[OH]D) and various bone markers in postmenopausal women with osteoporosis. This was a randomized, double-blind, active-controlled, prospective 16-week clinical trial conducted in 20 different hospitals. A total of 201 postmenopausal women with osteoporosis were assigned randomly to one of two groups: the IBN group, which received a once-monthly pill containing 150 mg ibandronate (n=99), or the IBN+ group, which received a once-monthly pill containing 150 mg ibandronate and 24,000 IU cholecalciferol (n=102). Serum levels of 25(OH)D, parathyroid hormone (PTH), and various bone markers were assessed at baseline and at the end of a 16-week treatment period. After 16 weeks of treatment, the mean serum levels of 25(OH)D significantly increased from 21.0 to 25.3 ng/mL in the IBN+ group but significantly decreased from 20.6 to 17.4 ng/mL in the IBN group. Additionally, both groups exhibited significant increases in mean serum levels of PTH but significant decreases in serum levels of bone-specific alkaline phosphatase and C-telopeptide of type 1 collagen (CTX) at 16 weeks; no significant differences were observed between the groups. However, in subjects with a vitamin D deficiency, IBN+ treatment resulted in a significant decrease in serum CTX levels compared with IBN treatment. The present findings demonstrate that a once-monthly pill containing ibandronate and cholecalciferol may be useful for the amelioration of vitamin D deficiency in patients with postmenopausal osteoporosis. Moreover, this treatment combination effectively decreased serum levels of resorption markers, especially in subjects with a vitamin D deficiency, over the 16-week treatment period.
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    ABSTRACT: Aim As serum beta-2-microglobulin (B2M) levels are usually elevated in patients with renal failure, they have been suggested as a surrogate marker of cardiovascular mortality for patients with chronic kidney disease. Glycation of B2M is cytotoxic and may contribute to the risk of diabetic complications in patients with diabetes. Our objective was to evaluate the relationship between B2M and diabetic complications in patients with type 2 diabetes (T2D) and normal kidney function. Methods A total of 366 patients with T2D and preserved renal function with no clinical evidence of cardiovascular disease were enrolled consecutively into this study. High B2M was defined as a median serum B2M level ≥ 1.8 mg/L. Subclinical atherosclerosis was defined as a carotid artery intima–media thickness (C-IMT) ≥ 0.9 mm or the presence of carotid plaque. The definition of diabetic nephropathy was based on the presence of albuminuria (≥ 30 mg/g creatinine). Results Patients with high B2M were older, and had diabetes of longer duration, higher serum creatinine, microalbuminuria, and increased vascular stiffness and C-IMT compared with patients with low B2M. B2M levels were positively correlated with C-IMT and vascular stiffness, and these associations remained constant after adjusting for age. In addition, after adjusting for age, gender, body mass index, serum creatinine, hypertension, smoking and alcohol consumption, the adjusted odds ratio (OR) for atherosclerosis was 2.01 [95% confidence interval (CI): 1.02–3.94] per 1 mg/L increase in B2M. The prevalences of diabetic retinopathy and nephropathy were significantly higher with a high B2M than with a low B2M. The multiple adjusted OR for diabetic nephropathy was 2.29 (95% CI: 1.11–4.72) per 1 mg/L increase of B2M. Conclusion Higher serum B2M was an independent risk factor for subclinical atherosclerosis and diabetic nephropathy in patients with T2D without renal impairment.
    Diabetes & Metabolism 10/2014; 40(6). DOI:10.1016/j.diabet.2014.08.002 · 2.85 Impact Factor
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    ABSTRACT: In this study, we evaluated the association between bone mineral density (BMD) and 10 single-nucleotide polymorphisms (SNPs) within eight osteoporosis susceptibility genes that were previously identified in genome-wide association studies (GWASs). A total of 494 men and 493 postmenopausal women participating in the Chungju Metabolic Disease cohort study in Korea were included. The following 10 SNPs were genotyped: ZBTB40 rs6426749, MEF2C rs1366594, ESR1 rs2941740, TNFRSF11B rs3134070, TNFRSF11B rs2073617, SOX6 rs711785, LRP5 rs599083, TNFSF11 rs227438, TNFSF11 rs9594782, and FOXL1 rs10048146; and the association between these SNPs and bone metabolism-related markers was assessed. Two SNPs, TNFSF11 rs2277438 and FOXL1 rs1004816, were associated with lumbar spine BMD. TNFSF11 rs2277438 in men and SOX6 rs7117858 and FOXL1 rs10048146 in postmenopausal women were found to be associated with lumbar BMD. ZBTB40 rs6426749, MEF2C rs1366594, and LRP5 rs599083 showed significant associations with femur neck BMD. These three SNPs in men and MEF2C rs1366594 and ESR1 rs2941740 in postmenopausal women were associated with femur neck BMD. A significant association between MEF2C rs1366594 and serum calcium levels was observed in men. Serum phosphorus levels were related to SOX6 rs7117858. Serum PTH levels were significantly associated with TNFRSF11B rs3134070 in men, and SOX6 rs711858 in postmenopausal women. In conclusion, our study independently confirmed associations between several SNPs: ZBTB40, MEF2C, ESR1, SOX6, LRP5, TNFSF11, and FOXL1 and bone marrow density in the Korean population.
    Endocrine Journal 08/2014; DOI:10.1507/endocrj.EJ14-0119 · 2.02 Impact Factor
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    ABSTRACT: Recently, klotho has been proposed as a link between cardiovascular diseases and premature aging, but the relationship between KLOTHO genes and cardiovascular risk factors, especially glucose metabolism, in humans is unclear. We investigate the relationship between polymorphisms G395A in promoter and C1818T in exon 4 of the KLOTHO gene with glucose metabolism and cardiovascular risk factors in Korean women. In 251 women (mean age 51.3+/-6.9 yr), body mass index (BMI), waist circumference, blood pressure, fasting plasma glucose, insulin and lipid profiles were measured. The genotyping of polymorphisms G395A in promoter and C1818T in exon 4 of the KLOTHO gene was performed by allelic discrimination using a 5' nuclease polymerase chain reaction assay. Allele frequencies of G395A polymorphism was 0.829 for the G allele and 0.171 for the A allele and allele frequencies of C1818T polymorphism were 0.804 for the C allele and 0.196 for the T allele, both of which were in compliance with Hardy-Weinberg equilibrium and the two polymorphisms were in linkage disequilibrium (D'=0.43, p<0.01). Mean systolic blood pressure was significantly higher in A allele carriers of G395A polymorphism compared with non-carriers, and the significance was persistent even after adjustment for age and BMI. Mean fasting plasma glucose was significantly higher in T allele carriers of C1818T polymorphism compared with non-carriers, and the significance was persistent even after adjustment for age and BMI. Subjects without any minor allele from either single nucleotide polymorphisms (SNP) had significantly lower mean values for systolic, diastolic blood pressure and fasting plasma glucose levels compared with subjects with both minor allele from either SNP. We observed that KLOTHO G395A polymorphism was associated with blood pressure and KLOTHO C1818T polymorphism was associated with glucose metabolism in Korean women. Further studies are needed to clarify this relationship.
    Journal of endocrinological investigation 07/2014; 29(7):613-8. DOI:10.1007/BF03344160 · 1.55 Impact Factor
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    ABSTRACT: Aims/IntroductionLittle is known about the long-term effects of Roux-en-Y gastric bypass (RYGB) in severely obese Asian individuals.Methods and MaterialsA total of 33 severely obese patients with type 2 diabetes underwent RYGB. All patients were followed up for 2 years. Visceral and abdominal subcutaneous fat areas were assessed using computed tomography (CT) before, and 12 and 24 months after RYGB. The muscle attenuation (MA) of paraspinous muscles observed by CT were used as indices of intramuscular fat.ResultsThe mean percentage weight loss was 22.2 ± 5.3% at 12 months, and 21.3 ± 5.1% at 24 months after surgery. Compared with the baseline values, the visceral fat area was 53.6 ± 17.1% lower 24 months after surgery, and the abdominal subcutaneous fat area was 32.7 ± 16.1% lower 24 months after surgery. The MA increased from 48.7 ± 10.0 at baseline to 52.2 ± 8.9 (P = 0.009) 12 months after surgery. The MA after the first 12 months maintained changes until 24 months. Triglycerides and free fatty acids were reduced after surgery, whereas the high-density lipoprotein cholesterol levels were increased significantly after surgery. At the last follow-up visit, 18 patients (55%) had diabetes remission. The percentage of iron and vitamin D deficiency was 30% and 52%, respectively.Conclusions We found that patients subjected to RYGB had significant sustained reductions in visceral and intramuscular fat. There were durable improvements in the cardiometabolic abnormalities without any significant comorbidities. However, there were mild nutritional deficiencies in these patients despite daily supplementation with multivitamins and minerals.
    03/2014; 5(2). DOI:10.1111/jdi.12137
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    Dong Jun Lim, Ki Hyun Baek
    09/2013; 28(3):243-4. DOI:10.3803/EnM.2013.28.3.243
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    ABSTRACT: The natural course of cytologically benign thyroid nodules remains unclear. The aim of this study was to evaluate whether ultrasonographic (US) changes are associated with changes in nodule volume during follow-up. We retrospectively reviewed over 4 years of clinical records of patients with benign thyroid nodules as confirmed by fine needle aspiration (FNA). In total, 186 patients with 202 benign thyroid nodules were included for study. We assessed for changes in nodule volume and examined the cystic portion of the nodule as well as four US features (echogenicity, margin, calcification pattern, and shape). During follow-up (mean, 21.7±10.7 months) and using 50% as a cutoff value, nodule volumes increased in 11.8%, exhibited no change in 79.9%, and decreased in 8.3% of patients. Proportion of nodules demonstrating at least one US change was 20.8% (42/202). The most common US changes (in descending order of frequency) were cystic change, margin change, and calcification pattern change. Nodule shape and echogenicity rarely changed. Increased nodule volume was not significantly associated with any US features or with the number of FNAs but was associated with younger age at time of diagnosis. Although a portion of thyroid nodules confirmed as benign showed US changes or volume changes during the follow-up period, these findings may only represent the natural course of benign nodules. Frequent follow-up with US might be needed for only a small number of cases with suspicious US findings.
    06/2013; 28(2):110-8. DOI:10.3803/EnM.2013.28.2.110
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    ABSTRACT: Background: 2-[18F]Fluoro-2-D-deoxyglucose (FDG)-positron emission tomography (PET) computed tomography (CT), which can detect a change in glucose metabolism in cancer cells, has been introduced as a diagnostic and prognostic tool in papillary thyroid carcinoma (PTC). However, differences in the clinicopathological and biological characteristics between primary PTCs with FDG uptake and those whithout FDG uptake are not well established. Methods: A total of 188 patients with PTC who had preoperative PET/CT scans were enrolled to compare the differences of clinicopathological parameters between FDG-avid (F-PTC) (n=150) and FDG-non-avid tumors (FN-PTC) (n=38). Immunohistochemical staining for glucose transporter (GLUT)-1 and hypoxia-inducible factor-1 alpha (HIF-1α) was performed. Results: FN-PTCs were smaller, had a lower incidence of lymphatic invasion, vascular invasion, multiplicity, and central lymph node metastasis, and had a lower maximum standardized uptake value than F-PTCs. After exclusion of high-risk patients for recurrence, FN-PTCs remained smaller (P<0.001) and had less lymphatic invasion (P=0.061). Among tumors larger than the spatial resolution of the PET/CT scan, macrocalcification was more frequent in FN-PTC than in F-PTC (P=0.043). While FN-PTC and F-PTC showed no difference in GLUT-1 expression (50% vs. 75%, P=0.363), FN-PTC showed lower immunoreactivity of HIF-1α than F-PTC (25.0% vs. 75.0%, P=0.032). Conclusion: Tumor size and macrocalcification are clinicopathological differences between FN-PTC and F-PTC. Biologically, HIF-1α may be responsible for increased FDG uptake in PTC.
    Thyroid: official journal of the American Thyroid Association 05/2013; DOI:10.1089/thy.2013.0051 · 3.84 Impact Factor
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    ABSTRACT: Recent studies suggest an association of vitamin D with obesity, diabetes and cardiovascular diseases. We analyzed the association of serum vitamin D level assessed by 25-hydroxyvitamin D(3) {25(OH)D(3)} with nonalcoholic fatty liver disease (NAFLD) in apparently healthy men. We performed a cross-sectional study of 6,567 Korean men who participated in a health screening program, evaluating the association of serum 25(OH)D(3) levels with the risk of NAFLD assessed by abdominal ultrasonogram. Of the participants, 43.6% had NAFLD and 21.1% had metabolic syndrome. Age, serum calcium, and aspartate aminotransferase levels showed weak but significant positive correlations with 25(OH)D(3) level; total cholesterol, triglycerides, low-density lipoprotein cholesterol and fasting insulin level showed weak but significant negative correlations with 25(OH)D(3) level. The mean 25(OH)D(3) level was significantly lower in participants with NAFLD than in those without (38.7 ± 9.0 vs. 39.7 ± 9.7 nmol/L, p < 0.001). When participants were divided into tertiles based on mean 25(OH)D(3) level, the proportion with NAFLD significantly increased as mean 25(OH)D(3) level decreased (40.0, 45.0 and 45.9%, p for linear trend < 0.001). Multiple logistic regression analyses with NAFLD as the dependent variable showed that the tertiles with lower 25(OH)D(3) levels had a significantly increased risk for NAFLD compared with the highest tertile, even after adjusting for body mass index and metabolic syndrome (OR 1.247 and 1.408 vs. the highest tertile, p < 0.001). Thus, participants with higher serum 25(OH)D(3) showed a significantly reduced risk for NAFLD compared with the low 25(OH)D(3) groups, independent of obesity and metabolic syndrome.
    Endocrine Journal 02/2013; DOI:10.1507/endocrj.EJ12-0387 · 2.02 Impact Factor
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    ABSTRACT: Recent data suggest that variations in calcium intake may influence body weight and composition; however, the relationship between daily calcium intake and muscle mass has not been well established. The objective of this study was to assess the relationship between daily calcium intake and sarcopenia. We analyzed data for older adults (over 60 years) from the fourth Korea National Health and Nutrition Examination Survey (KNHANES) conducted in 2009. A total of 1339 Non-Obese (BMI between 18.5 and 25 kg/m(2)), older adults (592 men and 707 women) were enrolled. Dietary variables were assessed using a nutrition survey that used a 24-hour recall method. Daily calcium intake based on the consumption of each food item was calculated. Sarcopenia was defined as an appendicular skeletal muscle mass divided by body weight less than 2 SD below the sex-specific mean for young adults. We found that daily calcium intake was negatively correlated with total body fat percentage and positively correlated with appendicular skeletal mass (p<0.001). Participants with sarcopenia appear to have significantly lower daily calcium intakes than participants without sarcopenia (p<0.001). The unadjusted prevalence of sarcopenia according to daily calcium intake tertiles were 6.3%, 4.3%, and 2.7% in tertiles 1, 2, and 3, respectively. After adjustment for age, sex, BMI, total energy intake, and lifestyle factors, compared with those in the lowest tertile of daily calcium intake, participants in the highest tertile had an odds ratio for sarcopenia of 0.295 (95% confidence interval, 0.087-0.768; p for trend = 0.014). We found that daily calcium intake, corrected for total energy intake and serum 25(OH)D status, was significantly lower in subjects with sarcopenia than in those without. Our results suggest a strong inverse association between daily calcium intake and sarcopenia in non-obese, older Korean adults.
    Endocrine Journal 01/2013; DOI:10.1507/endocrj.EJ12-0395 · 2.02 Impact Factor
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    ABSTRACT: Some papers have suggested that alkaline phosphatase (ALP) level is a predictor of the metabolic syndrome (MetS) in the general population. However, the association is still controversial, and the mechanisms underlying an association between ALP level and the MetS have not been elucidated. We analyzed the association between serum ALP level and the development of the MetS over a 4-year period. A total of 14,224 subjects who visited the Health Promotion Center for a medical examination in 2005 were followed up after 4 years. Serum ALP level correlated positively with body fat mass and visceral fat mass. The adjusted geometric mean ALP levels were higher in subjects with elevated C-reactive protein level or greater fat mass (P < 0.001). None of the subjects had the MetS at baseline, but 1,179 exhibited the MetS at the 4-year follow-up. After multiple adjustments, the odds ratio (OR) was substantially higher for development of the MetS (OR 1.56, 95% confidence intervals, 1.21-2.01) in subjects in the highest ALP quintile compared with those in the lowest quintile. After adjusting for various covariates, we found significant associations between the quintile of serum ALP level and abdominal obesity, low high-density lipoprotein cholesterol level, and high triglyceride level. Higher serum ALP level was a significant predictor of the MetS in middle-aged Koreans. Serum ALP level correlated positively with body fat mass and independently with a more atherogenic lipid profile in the general population in Korea.
    Endocrine Journal 11/2012; DOI:10.1507/endocrj.EJ12-0331 · 2.02 Impact Factor
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    ABSTRACT: Background: Galectin-3 (G3) immunostaining of fine-needle aspiration (FNA) samples from thyroid nodules is very useful for the diagnosis of malignancy. The objective of the present study was to determine whether the absence of G3 immunostaining in preoperative FNA samples is associated with favorable clinicopathological parameters, including lymph node (LN) metastasis, in papillary thyroid carcinoma (PTC). Methods: The records of 868 patients with PTC who had prethyroidectomy ultrasonography-guided FNA with G3 immunostaining between January 2006 and December 2009 were retrospectively reviewed. G3 immunostaining was considered positive if the percentage of tumor cells showing definite cytoplasmic immunostaining exceeded 5%. Patients who had negative G3 immunostaining of FNA samples were assigned to the G3-negative (G3N) group; whereas those who had positive G3 immunostaining were assigned to the G3-positive (G3P) group. Results: There were 92 patients who were assigned to the G3N group (10.6%) because of the negative staining for G3 in the preoperative FNA samples from their thyroid nodules. The proportion of PTC subtypes in the G3N and G3P groups was similar (p=0.376). There was less frequent thyroid capsular invasion (46.7% vs. 66.5%, p<0.001), extrathyroidal extension (28.3% vs. 48.5%, p<0.001), and LN metastasis (22.2% vs. 48.7%, p<0.001) in the G3N group than the G3P group. In multivariate regression analysis, G3N expression predicted a lower risk of LN metastasis (odds ratio=0.37, 95% confidence interval 0.18-0.78) after adjustment for other clinicopathological parameters. Over a median follow-up of 33 months, no association was observed between G3N and disease-free survival. Conclusion: The absence of G3 expression in FNA samples from PTC is associated with pathological parameters considered less aggressive than is the case for PTCs with G3 expression, including being a negative predictor of negative LN involvement. Long-term follow-up studies, however, are needed to verify whether G3N patients have lower recurrence and mortality rates.
    Thyroid: official journal of the American Thyroid Association 08/2012; 22(12). DOI:10.1089/thy.2011.0166 · 3.84 Impact Factor
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    ABSTRACT: The aim of this study was to investigate the influences of visceral adiposity on cardiovascular autonomic neuropathy (CAN) in patients with type 2 diabetes mellitus. Two hundred eleven patients with type 2 diabetes participated in this study. Anthropometric and metabolic parameters were measured, and the visceral fat area was assessed using computed tomography. CAN was diagnosed using a cardiovascular reflex test. We analyzed the correlation between the visceral fat area and each parameter in this test. The mean age, body mass index (BMI), and duration of diabetes of the study population were 60±14 years (mean±standard deviation), 25.1±4.2 kg/m(2), and 12.3±8.9 years, respectively. The visceral fat area showed positive correlations with age, BMI, waist circumference, and subcutaneous fat area. There was no statistically significant difference in the cardiovascular reflex test outcome between genders. Univariate linear regression analysis showed that an increased visceral fat area diminished good heart rate response to a Valsalva maneuver (R(2)=4.9%, P=0.013 in an unadjusted model), but only in women. This statistical association was preserved after adjusting for age and BMI (R(2)=9.8%, P=0.0072). The results of this study suggest that visceral adiposity contributes to an autonomic imbalance to some degree, as demonstrated by the impaired cardiovascular reflex test among women with type 2 diabetes.
    Diabetes & metabolism journal 08/2012; 36(4):285-92. DOI:10.4093/dmj.2012.36.4.285
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    ABSTRACT: BACKGROUND: Transfusional iron overload primarily results in reticuloendothelial iron accumulation, which is considered to be less harmful than parenchymal iron accumulation. However, systematic and comprehensive data on endocrine function in transfusion-associated hemochromatosis are limited. METHODS: We examined 25 aplastic anemia patients (11 men and 14 women) diagnosed with transfusion-associated hemochromatosis at a single institution. Pituitary function was determined with a combined pituitary function test. On a different day, a 75 g oral glucose tolerance test was performed. The bone mineral density (BMD) of the lumbar spine and total hip was assessed with dual-energy X-ray absorptiometry. RESULTS: Twenty-two (88%) of these 25 patients had at least one endocrine abnormality, and 12 had more than one abnormality. The most common pituitary hormonal deficiency involved the pituitary-gonadal axis; 54% of the total subjects had hypogonadotropic hypogonadism. Two patients had an insufficient cortisol response to corticotropin-releasing hormone stimulation. No patient had a deficiency of growth hormone or thyroid-stimulating hormone. Twelve (48%) had diabetes mellitus and these patients tended to have higher concentrations of ferritin, alanine aminotransferase, and γ-glutamyl transferase. Osteoporosis (T-score < -2.5 SD) was observed in 48% of patients. The reduction in BMD was more pronounced in the lumbar spine than in the total hip. The patients with osteoporosis were accompanied by hypogonadism, which predominantly affected the trabecular bone. CONCLUSIONS: Our observations suggest that endocrinopathies are common in transfusion-associated hemochromatosis. © 2012 Blackwell Publishing Ltd.
    Clinical Endocrinology 07/2012; DOI:10.1111/j.1365-2265.2012.04495.x · 3.35 Impact Factor
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    ABSTRACT: We prospectively examined the association between type 2 diabetes mellitus (T2DM) progression and common T2DM-risk gene variants in 870 non-diabetic participants in a Chungju Metabolic Disease Cohort Study in Korea. We genotyped the following six single nucleotide polymorphisms (SNPs): KCNQ1 (potassium voltage-gated channel, KQT-like subfamily member 1) rs2237892, CDKAL1 (regulatory subunit-associated protein 1-like 1) rs7554840, CDKN2A/B (cyclin-dependent kinase inhibitor 2A/B) rs1081161, SCL30A8 (solute carrier family 30 member 8 gene) rs13266634, TCF7L2 (transcription factor 7-like 2) rs7903146, and PPARG (peroxisome proliferator activated receptor gamma) rs1801282. Anthropometric data and metabolic parameters were obtained at baseline and year 4. Pancreatic β cell function was assessed by the homeostasis model assessment index of β cells (HOMA-β). After 4 years, 137 subjects developed T2DM (15.7%). A significant association was found in the variant of KCNQ1 rs2237892, whereas the SNPs of CDKAL1, CDKN2A/B, SCL30A8, TCF7L2 and PPARG were not associated. The C-allele carriers of KCNQ1 conferred a significantly increased risk for T2DM compared with the T/T genotype, independently of clinical risk factors (odds ratio=2.61, 95% confidence intervals=1.02-6.69, P=0.04). Although no differences were observed at baseline among the KCNQ1 variants, HOMA-β levels by year 4 were significantly lower in the C-allele carriers after controlling for metabolic parameters. The genetic variations in KCNQ1 are associated with future development of T2DM in Koreans, which might be mediated by differences in insulin secretory function.
    Journal of Human Genetics 03/2012; 57(4):265-8. DOI:10.1038/jhg.2012.16 · 2.53 Impact Factor
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    ABSTRACT: We aimed to examine the relationship between iron status and hypertension as few studies have addressed this. We analyzed the association between ferritin/total iron-binding capacity (TIBC) and the subsequent development of hypertension. A total of 8,580 men who visited the Health Promotion Center for a medical checkup in 2005 were followed-up after 4 years. Of the 8,580 men who were not hypertensive at baseline, 818 were found to be hypertensive at the 4-year follow-up. Compared with those who remained normotensive, these hypertensive subjects had higher levels of ferritin and TIBC at baseline, but had no significant difference in iron levels. After adjustment for age and body mass index (BMI), the odds ratios (OR) was substantially higher for new hypertension (OR 1.54, 95% confidence intervals (CIs) 1.26-1.88; P for trend <0.001) in subjects with the highest ferritin quartiles compared with those in the lowest quartiles. The association of serum ferritin levels with the incidence of hypertension was unchanged after adjustment for baseline blood pressure (BP). Adjustment for insulin resistance as measured by the homeostasis model assessment and the presence of a fatty liver reduced the magnitude of the OR for hypertension (first quartile reference, fourth quartiles OR 1.24, 95% CI 1.01-1.53, P for trend = 0.012), but did not affect their statistical significance. Serum ferritin, but not iron level, was a significant predictor of hypertension in middle-aged Korean men. Fatty liver disease and insulin resistance may be mediators of this high ferritin-hypertension association.
    American Journal of Hypertension 01/2012; 25(4):492-7. DOI:10.1038/ajh.2011.241 · 3.40 Impact Factor
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    ABSTRACT: An association between vitamin D status and sarcopenia has not been shown in a community-dwelling cohort, despite the well-documented relationship between vitamin D status and falls. Our objective was to investigate whether vitamin D level is associated with sarcopenia in older Koreans. The Fourth Korea National Health and Nutrition Examination Survey in the Korean population was conducted in 2009. Participants included 1380 men and 1789 women aged 50 yr or older. Serum 25-hydroxyvitamin D [25(OH)D] and PTH levels were measured. Sarcopenia was defined as an appendicular skeletal muscle mass divided by body weight that was less than 2 sd below the sex-specific mean for young adults. Obesity was defined as a body mass index (BMI) of 27.5 kg/m(2) or higher. 25(OH)D level correlated negatively with appendicular fat mass and positively with appendicular skeletal mass. The groups with sarcopenic obesity and sarcopenia only had lower 25(OH)D levels than did the nonsarcopenia groups. However, 25(OH)D levels did not differ between the sarcopenic obesity and sarcopenia groups. After adjustment for age, sex, BMI, and lifestyle factors, compared with those in the lowest quartile of 25(OH)D level, participants in the highest quartile had an odds ratio for sarcopenia of 0.47 (95% confidence interval = 0.30-0.73; P for trend = 0.001). There was no association between PTH and sarcopenia after adjustment of BMI. Vitamin D levels were significantly lower in subjects with sarcopenia than in those without, regardless of obesity. We found a strong inverse association between 25(OH)D level and sarcopenia in the older Korean population.
    The Journal of Clinical Endocrinology and Metabolism 08/2011; 96(10):3250-6. DOI:10.1210/jc.2011-1602 · 6.31 Impact Factor