Computed tomography evaluation of skeletal muscle quality and quantity in people with morbid obesity with and without metabolic abnormality.

We investigated the differences in quantity and quality of skeletal muscle between metabolically healthy obese (MHO) and metabolically unhealthy obese (MUO) individuals using abdominal CT. One hundred and seventy-two people with morbid obesity who underwent bariatric surgery and 64 healthy control individuals participated in this retrospective study. We divided the people with morbid obesity into an MHO and MUO group. In addition, nonobese metabolic healthy people were included analysis to provide reference levels. CT evaluation of muscle quantity (at the level of the third lumbar vertebra [L3]) was performed by calculating muscle anatomical cross-sectional area (CSA), which was normalized to patient height to produce skeletal muscle index (SMI). Muscle quality was assessed as skeletal muscle density (SMD), which was calculated from CT muscle attenuation. To characterize intramuscular composition, muscle attenuation was classified into three categories using Hounsfield unit (HU) thresholds: -190 HU to -30 HU for intermuscular adipose tissue (IMAT), -29 to +29 HU for low attenuation muscle (LAM), and +30 to +150 HU for normal attenuation muscle (NAM). People with morbid obesity comprised 24 (14%) MHO individuals and 148 (86%) MUO individuals. The mean age of the participants was 39.7 ± 12.5 years, and 154 (65%) participants were women. MUO individuals had a significantly greater total skeletal muscle CSA than MHO individuals in the model that adjusted for all variables. Total skeletal muscle SMI, SMD, NAM index, LAM index, and IMAT index did not differ between MHO and MUO individuals for all adjusted models. Total skeletal muscle at the L3 level was not different in muscle quantity, quality, or intramuscular composition between the MHO and MUO individuals, based on CT evaluation. MHO individuals who are considered "healthy" should be carefully monitored and can have a similar risk of metabolic complications as MUO individuals, at least based on an assessment of skeletal muscle.

Endocrine disorders associated with obesity.

Several endocrine disorders, including diabetes, insulinoma, Cushing syndrome, hypothyroidism, polycystic ovarian syndrome, and growth hormone deficiency, are associated with obesity. The mechanisms underlying the development of obesity vary according to the abnormalities of endocrine function. The primary actions of insulin, glucocorticoids (GCs), thyroid hormone, and growth hormone are associated with energy metabolism in the liver, muscle, adipose tissue, and other tissues. This chapter describes the pathogenesis of obesity and metabolic dysfunction associated with excess insulin or GCs and the deficiency of thyroid hormone or growth hormone.

Subclinical thyroid dysfunction and chronic kidney disease: a nationwide population-based study.

BACKGROUND: Chronic kidney disease (CKD) has a significant impact on global health. Studies have shown that subclinical thyroid dysfunction may be related to CKD, but the association between subclinical thyroid dysfunction and CKD in the general population is unclear. We aimed to evaluate the risk of CKD according to thyroid function status in a large cohort. METHODS: We analyzed data from a nationwide, population-based, cross-sectional survey (KNHANES VI). A total of 3,257 participants aged ≥ 19 years who underwent thyroid and kidney function assessments were included in this study. CKD was defined as an estimated glomerular filtration rate < 60 mL/min/1.73 m2 and/or urine albumin-creatinine ratio ≥ 30 mg/g. The risk of CKD according to thyroid function status was assessed using logistic regression, adjusted for potential confounders. RESULTS: Overall, 6.7% of the participants had CKD. There were no significant differences in thyroid-stimulating hormone and free thyroxine levels between the groups with and without CKD. The proportion of participants with CKD was significantly different among the thyroid function status groups (p = 0.012) and tended to increase significantly in the following order: subclinical hyperthyroidism (1.5%), euthyroidism (6.6%), and subclinical hypothyroidism (12.6%) (p for trend < 0.001). Subclinical hypothyroidism was a significant risk factor for CKD, even after adjusting for sex, age, household income, education, smoking, alcohol consumption, walking activity, abdominal obesity, hypertension, low high-density lipoprotein cholesterol, elevated triglycerides, hyperglycemia, free thyroxine, and thyroid-peroxidase anibody (odds ratio 2.161, 95% confidence interval 1.032-4.527, p = 0.041). CONCLUSION: Subclinical hypothyroidism is an independent predictor of CKD in the general population.

Association between iodine intake and metabolic syndrome in euthyroid adult in an iodine-replete area: a nationwide population-based study.

Metabolic syndrome (MetS) is considered very important because of the increased risk for cardiovascular diseases. Identifying modifiable factors may help prevent MetS. We aimed to investigate the relationship between iodine intake as a dietary factor and MetS in euthyroid adult in an iodine-replete area. A total of 4,277 adult aged ≥19 years from the Korea National Health and Nutrition Examination Survey VI (2013-2015) with urinary iodine concentration (UIC) results and normal thyroid function were included. Participants were grouped according to their iodine nutrition status based on the WHO recommendations and modifications: insufficient (<100 µg/L), adequate (100-299 µg/L), and excessive (≥300 µg/L) iodine intake. We estimated the odds ratios (ORs) for MetS according to the UIC groups using logistic regression models. Of the study participants, 27.2% men and 23.9% women had MetS. Men with excessive iodine intake had a significantly lower risk of elevated triglycerides [OR 0.733, 95% confidence interval (CI) 0.603-0.890, p = 0.010], as compared to those with adequate iodine intake. Women with insufficient iodine intake had a significantly greater risk of elevated blood glucose (OR 1.519, 95% CI 1.011-2.282, p = 0.044), as compared to those with adequate iodine intake. In women, insufficient iodine intake was a significant risk factor for MetS compared to adequate iodine intake, even after adjusting for confounding variables including age, smoking, alcohol consumption, walking activity, serum thyroid-stimulating hormone, free thyroxine, and anti-thyroid peroxidase antibody (OR 1.544, 95% CI 1.031-2.311, p = 0.035). There was no association between iodine intake and risk of MetS in men. In conclusion, insufficient iodine intake was associated with an increased risk of MetS only in euthyroid adult women. Our data support that sex differences may influence the relationship between iodine intake as a dietary pattern and MetS.

Risk of carotid plaques according to triglyceride-glucose index stratified by thyroid function: A cross-sectional study.

BACKGROUND: Recent studies have indicated that the triglyceride-glucose (TyG) index or subclinical thyroid dysfunction is associated with carotid plaques, a predictor of cardiovascular disease risk. However, evidence for this association is limited and inconsistent. This study aimed to evaluate the risk of carotid plaques according to TyG index and thyroid function status in the general population. METHODS: A total of 2,931 individuals who underwent carotid ultrasound as part of a comprehensive health examination at the Health Promotion Center of Soonchunhyang University Hospital were retrospectively reviewed. Based on the TyG index and thyroid function status, the participants were divided into six groups: LoTyG-SHyper (low TyG index with subclinical hyperthyroidism), LoTyG-Eu (low TyG index with euthyroidism), LoTyG-SHypo (low TyG index with subclinical hypothyroidism), HiTyG-SHyper (high TyG index with subclinical hyperthyroidism), HiTyG-Eu (high TyG index with euthyroidism), and HiTyG-SHypo (high TyG index with subclinical hypothyroidism). A multivariate logistic regression analysis was conducted to determine the risk of carotid plaques. RESULTS: The proportion of participants with significant carotid plaques was significantly different among the six groups (p<0.001, p for trend<0.001). The odds ratio (OR) and 95% confidence interval (CI) for significant carotid plaques were significantly higher in the HiTyG-SHypo group than in the LoTyG-Eu group, even after adjusting for confounding variables including sex, age, smoking, obesity, hypertension and diabetes mellitus (OR 1.506, 95% CI 1.045-2.170, p = 0.028). The OR of significant carotid plaques was higher in the HiTyG-Eu group than in the LoTyG-Eu group; however no associations were observed after additional adjustment for confounding variables. CONCLUSION: The TyG index and thyroid function status are important predictors of the risk of carotid plaques in healthy individuals. Early evaluation of carotid plaques may be necessary for subjects with high insulin resistance and subclinical hypothyroidism.

Association of thyroid autoimmunity with nonalcoholic fatty liver disease in euthyroid middle-aged subjects: A population-based study.

BACKGROUND AND AIM: The association between thyroid autoimmunity and nonalcoholic fatty liver disease (NAFLD) remains unclear. In this study, we aimed to investigate the relationship between thyroid autoimmunity and NAFLD in a large cohort of euthyroid subjects. METHODS: We analyzed clinical and biochemical data from a nationwide, population-based, cross-sectional survey (KNHANES VI). A total of 1589 middle-aged participants aged 45-65 years, with normal thyroid function, were included in this study. NAFLD was defined as a hepatic steatosis index of > 36. We estimated the odds ratios (ORs) for NAFLD according to anti-thyroid peroxidase antibody (TPOAb) positivity by using logistic regression models, and adjusted for potential confounders. RESULTS: Overall, 24% (n = 378) of the subjects had NAFLD. Subjects with NAFLD showed a higher positivity for TPOAb (11% vs 7%, P = 0.014) compared with those without NAFLD. TPOAb positivity was a significant risk factor for NAFLD [OR 1.668, 95% confidence interval (CI) 1.019-2.730, P = 0.042] even after adjusting for confounding variables, including age, sex, household income, education, smoking, alcohol consumption, walking activity, abdominal obesity, elevated blood pressure, dyslipidemia and hyperglycemia. In addition, TPOAb positivity predicted the risk of advanced liver fibrosis (OR 3.112, 95% CI 1.256-7.713, P = 0.014) in subjects with NAFLD, independent of the confounding variables. CONCLUSION: In euthyroid subjects, thyroid autoimmunity is associated with NAFLD and advanced liver fibrosis, independent of known metabolic risk factors. Large longitudinal studies in the future will help clarify the causality.

A Real-World Study of Long-Term Safety and Efficacy of Lobeglitazone in Korean Patients with Type 2 Diabetes Mellitus.

BACKGROUND: Thiazolidinediones (TZDs) have been associated with various safety concerns including weight gain, bladder cancer, and congestive heart failure (CHF). This study evaluated the efficacy and safety of lobeglitazone, a novel TZD in patients with type 2 diabetes mellitus (T2DM) in real practice. METHODS: In this non-interventional, multi-center, retrospective, and observational study conducted at 15 tertiary or secondary referral hospitals in Korea, a total of 2,228 patients with T2DM who received lobeglitazone 0.5 mg for more than 1 year were enrolled. RESULTS: Overall adverse events (AEs) occurred in 381 patients (17.10%) including edema in 1.97% (n=44). Cerebrovascular and cardiovascular diseases were identified in 0.81% (n=18) and 0.81% (n=18), respectively. One case of CHF was reported as an AE. Edema occurred in 1.97% (n=44) of patients. Hypoglycemia occurred in 2.47% (n=55) of patients. Fracture occurred in 1.17% (n=26) of all patients. Lobeglitazone significantly decreased HbA1c level, resulting in a mean treatment difference of -1.05%± 1.35% (P<0.001), and decreased total cholesterol, triglyceride, and low-density lipoprotein cholesterol. However, it increased high-density lipoprotein cholesterol, regardless of statin administration. The patients who received lobeglitazone 0.5 mg showed an apparent reduction in glycosylated hemoglobin (HbA1c) from baseline during the first 6 months of treatment. The HbA1c levels remained stable between months 6 and 42. CONCLUSION: Lobeglitazone has long-term safety profile, good glycemic-lowering effect and long-term durability of glycemic control in real-world clinical settings.

Efficacy of Differential Diagnosis of Thyroid Nodules by Shear Wave Elastography-the Stiffness Map.

BACKGROUND: Fine needle aspiration is the gold standard for differential diagnosis of thyroid nodules; however, the malignancy rate for indeterminate cytology is 20% to 50%. OBJECTIVE: We evaluated the efficacy of shear wave elastography added to ultrasonography for differential diagnosis of thyroid nodules. METHODS: We retrospectively reviewed the medical records of 258 consecutive patients. Thyroid nodules were divided into 4 categories according to maximum elasticity (EMax) and nodule depth/width (D/W) ratio: Category 1 (EMax ≥ 42.6 kPa; D/W < 0.9); Category 2 (EMax < 42.6 kPa; D/W < 0.9); Category 3 (EMax ≥ 42.6 kPa; D/W ≥ 0.9); and Category 4 (EMax < 42.6 kPa; D/W ≥ 0.9). The EMax cutoff value was set using receiver operating characteristic (ROC) curve analysis to predict nodular hyperplasia (NH) vs follicular neoplasm (FN). Cutoff value for nodule D/W ratio was set using ROC curve analysis for malignancy. RESULTS: NH was the most prevalent pathology group in Category 1, FN in Category 2, and papillary thyroid carcinoma in Category 3. Category 3 demonstrated the highest rate of malignancy (81.8%) and had 55.4% sensitivity and 90% specificity for predicting malignancy. When assessing the benign pathology of NH in follicular patterned lesion, Category 1 demonstrated the highest NH prevalence of 88.9% (34/37) and had 73.9% sensitivity and 85.0% specificity. CONCLUSION: The performance for malignancy was highest in Category 3 and predictive ability for benign pathology of NH in follicular lesion was highest in Category 1. The information of EMax and nodule D/W ratio was useful to predict the pathology of thyroid nodules.

Thyroid autoimmunity and metabolic syndrome: a nationwide population-based study.

OBJECTIVE: Recent studies have reported that thyroid hormone levels are associated with metabolic syndrome (MetS) even in euthyroid subjects. However, the association between thyroid autoimmunity and MetS is uncertain. This study aimed to investigate the relationship between thyroid autoimmunity and MetS in a large cohort study of euthyroid subjects. METHODS: A total of 4775 participants aged ≥19 years from the Korea National Health and Nutrition Examination Survey VI (2013-2015) with anti-thyroid peroxidase antibody (TPOAb) results and normal thyroid functions were included in this study. Subjects were grouped according to thyroid autoimmunity (positivity of TPOAb). We estimated the odds ratios (ORs) for MetS according to TPOAb positivity using logistic regression models, adjusted for potential confounders. RESULTS: Of the study subjects, 25% (n = 1206) were diagnosed with MetS. Subjects with MetS showed higher median TPOAb levels (6.3 vs 6.8 IU/mL, P < 0.001) and higher positivity of TPOAb (5 vs 7%, P = 0.002) than those without MetS. There was a significant difference in prevalence of MetS depending on the TPOAb positivity (25% vs 33%, P = 0.002). Subjects with TPOAb positive had a significantly greater risk of abdominal obesity (OR 1.675, 95% CI: 1.302-2.154, P < 0.001), low high-density lipoprotein cholesterol (OR: 1.603, 95% CI: 1.244-2.066, P < 0.001) and elevated blood pressure (OR: 1.418, 95% CI: 1.099-1.829, P = 0.007) as compared to those with TPOAb negative. Positivity of TPOAb was a significant risk factor for MetS even after adjusting for confounding variables including age, sex, household income, education, smoking, alcohol consumption, walking activity, thyroid-stimulating hormone and free thyroxine (OR: 1.389, 95% CI: 1.048-1.841, P = 0.022). CONCLUSION: In euthyroid subjects, thyroid autoimmunity is associated with MetS. Further large longitudinal studies are needed to clarify causality.

Effect of bariatric surgery on circulating and urinary mitochondrial DNA copy numbers in obesity with or without diabetes.

INTRODUCTION: Recent studies have suggested that extracellular circulating and urinary mitochondrial DNA (mtDNA) are associated with mitochondrial dysfunction in obesity and type 2 diabetes mellitus (T2DM). However, the changes to cell-free serum and urinary mtDNA after bariatric surgery in patients with obesity with T2DM have not been investigated to date. RESEARCH DESIGN AND METHODS: We prospectively recruited patients with obesity (n=18), and with obesity and T2DM (n=14) who underwent bariatric surgery, along with healthy volunteers (HV) as a control group (n=22). Serum and urinary mitochondrial nicotinamide adenine dinucleotide dehydrogenase subunit-1 (mtND-1) and cytochrome-c oxidase 3 (mtCOX-3) copy numbers were measured using quantitative PCR (qPCR). The mtDNA copy numbers of patients with obesity (with and without T2DM) were followed up 6 months after surgery. RESULTS: The copy numbers of urinary mtND-1 and mtCOX-3 in patients with obesity, with or without T2DM, were higher than those in the HVs. Moreover, urinary mtCOX-3 copy number increased in patients with obesity with T2DM compared with patients with obesity without T2DM (p=0.018). Meanwhile, serum mtCOX-3 copy numbers in HV were higher in both obesity patient groups (p=0.040). Bariatric surgery reduced urinary mtND-1 and mtCOX-3 copy numbers, as well as serum mtCOX-3 copy numbers only in patients with obesity with T2DM. CONCLUSION: These results suggest that T2DM induces greater kidney mitochondrial dysfunction in patients with obesity, which can be effectively restored with bariatric surgery.

Shear wave elasticity by tracing total nodule showed high reproducibility and concordance with fibrosis in thyroid cancer.

BACKGROUND: Although shear wave elastography (SWE) is reported to be useful in detecting malignant thyroid nodules, it shows a wide range of cut-off values of elasticity index (EI) in detecting malignant nodules. The cause of discrepancy remains unclear. Fibrosis of the tumors is known to increase the EI in SWE, and matching of SWE and surgical histopathology has not been fully illustrated in thyroid cancer. We aimed to evaluate the reproducibility of the new total nodular region of interest (ROI) method excluding the subjective features of focal circular ROI placement and to determine the lesion that causes the elevation of EI on SWE and on histopathology. METHODS: A total of 29 thyroid cancers from 28 patients were included. We evaluated the reproducibility of EI in the new total nodular ROI using Q-Box Trace program and compared the EI in focal nodular ROI using a 3-mm circular area. We analyzed the correlation between fibrosis and EI. RESULT: The coefficient of variation (CV) of the intrarater assay was significantly lower in total nodular ROI than in focal nodular ROI within the image in rater 1 (1.7% vs. 13.4%, p < 0.001) and in rater 2 (1.4% vs. 16.9%, p < 0.001) and in different images in rater 1 (7.6% vs. 12.3%, p = 0.040) and in rater 2 (7.5% vs. 19.8%, p = 0.004). Moreover, CV of the interrater assay showed similar results (14.9% vs. 19%, p = 0.030). Interrater intraclass correlation coefficient showed better agreement in total nodular ROI than in focal nodular ROI (0.863 vs. 0.783). The degree of fibrosis on histopathology showed significant correlations with EI (EMean, p < 0.001; EMax, p = 0.027), and the location of fibrosis was concordant with the high EI area on SWE. CONCLUSION: Our study revealed that the new total nodular ROI method showed higher reproducibility and better agreement in intra- and interrater assay than the focal nodular ROI method, suggesting a valuable and standardized method in clinical practice. Moreover, our results showed that fibrosis in the histopathology increased EI on SWE and might lead to the discrepancy of the cut-off values in detecting thyroid cancer.

Utility of shear wave elastography to detect papillary thyroid carcinoma in thyroid nodules: efficacy of the standard deviation elasticity.

BACKGROUND/AIMS: The aim of this study was to address the role of the elasticity index as a possible predictive marker for detecting papillary thyroid carcinoma (PTC) and quantitatively assess shear wave elastography (SWE) as a tool for differentiating PTC from benign thyroid nodules. METHODS: One hundred and nineteen patients with thyroid nodules undergoing SWE before ultrasound-guided fine needle aspiration and core needle biopsy were analyzed. The mean (EMean), minimum (EMin), maximum (EMax), and standard deviation (ESD) of SWE elasticity indices were measured. RESULTS: Among 105 nodules, 14 were PTC and 91 were benign. The EMean, EMin, and EMax values were significantly higher in PTCs than benign nodules (EMean 37.4 in PTC vs. 23.7 in benign nodules, p = 0.005; EMin 27.9 vs. 17.8, p = 0.034; EMax 46.7 vs. 31.5, p < 0.001). The EMean, EMin, and EMax were significantly associated with PTC with diagnostic odds ratios varying from 6.74 to 9.91, high specificities (86.4%, 86.4%, and 88.1%, respectively), and positive likelihood ratios (4.21, 3.69, and 4.82, respectively). The ESD values were significantly higher in PTC than in benign nodules (6.3 vs. 2.6, p < 0.001). ESD had the highest specificity (96.6%) when applied with a cut-off value of 6.5 kPa. It had a positive likelihood ratio of 14.75 and a diagnostic odds ratio of 28.50. CONCLUSION: The shear elasticity index of ESD, with higher likelihood ratios for PTC, will probably identify nodules that have a high potential for malignancy. It may help to identify and select malignant nodules, while reducing unnecessary fine needle aspiration and core needle biopsies of benign nodules.

Association between Serum Cystatin C and Vascular Complications in Type 2 Diabetes Mellitus without Nephropathy.

BACKGROUND: Recent studies have correlated serum cystatin C (CysC) with vascular complications, but few studies have investigated this correlation in diabetes patients without nephropathy. This study aimed to evaluate if higher serum CysC levels increase the risk for vascular complications in type 2 diabetes mellitus patients with normal renal function or mild renal impairment. METHODS: A total of 806 consecutive patients with type 2 diabetes mellitus who were admitted to the diabetes center of Soonchunhyang University Hospital for blood glucose control were retrospectively reviewed. Patients with nephropathy were excluded. Subjects were categorized into quartiles of serum CysC levels (Q1, ≤0.65 mg/L; Q2, 0.66 to 0.79 mg/L; Q3, 0.80 to 0.94 mg/L; and Q4, ≥0.95 mg/L). RESULTS: The proportion of patients with diabetic retinopathy (DR) (P for trend <0.001), coronary heart disease (CHD) (P for trend <0.001), and stroke (P for trend <0.001) increased across the serum CysC quartiles. After adjustment for confounding factors, the highest serum CysC level remained a significant risk factor for DR (odds ratio [OR], 1.929; 95% confidence interval [CI], 1.007 to 4.144; P=0.040). Compared with Q1, a significant positive association was observed between serum CysC and CHD in Q2 (OR, 7.321; 95% CI, 1.114 to 48.114; P=0.012), Q3 (OR, 6.027; 95% CI, 0.952 to 38.161; P=0.020), and Q4 (OR, 8.122; 95% CI, 1.258 to 52.453; P=0.007). No associations were observed between CysC and stroke after additional adjustment for confounding variables. CONCLUSION: Serum CysC levels are independently associated with DR and CHD, suggesting that CysC may be useful for identifying type 2 diabetes mellitus patients without nephropathy who are at high risk for vascular complications.

Efficacy of Shear-Wave Elastography for Detecting Postoperative Cervical Lymph Node Metastasis in Papillary Thyroid Carcinoma.

AIMS: To evaluate shear-wave elastography (SWE) as a tool to detect postoperative cervical lymph node (LN) metastasis in patients with papillary thyroid carcinoma (PTC). METHODS: Forty-three LNs of 43 patients with PTC undergoing ultrasound (US) and SWE before ultrasound-guided fine-needle aspiration (FNA) for the evaluation of postoperative cervical LN recurrences were analyzed. The mean (EMean), minimum (EMin), maximum (EMax), and standard deviation (ESD) of SWE elasticity indices were measured. RESULTS: Among 43 indeterminate or suspicious LNs, 12 were malignant and 31 were benign. The EMean, EMin, EMax, and ESD values were significantly higher in malignant LNs than in benign LNs (EMean: 37.1 kPa in malignant versus 11.8 kPa in benign LNs, P < 0.001; EMin: 11.3 kPa versus 5.1 kPa, P = 0.046; EMax: 50.5 kPa versus 23.7 kPa, P < 0.001; and ESD: 7.8 kPa versus 4.1 kPa, P = 0.006). EMax had the highest accuracy (93.0%) when applied with a cut-off value of 37.5 kPa. It had a positive likelihood ratio of 25.83 and a diagnostic odds ratio of 150.0. CONCLUSIONS: The shear elasticity index of EMax, with higher likelihood ratios for malignant LNs, may help identify postoperative cervical LN metastasis in PTC patients with indeterminate or suspicious LNs.

Iodine intake as a risk factor for BRAF mutations in papillary thyroid cancer patients from an iodine-replete area.

PURPOSE: Both deficient and excessive iodine intake leads to thyroid disease, which shows U-shaped curves. Our previous study showed that a relatively low [urinary iodine concentration (UIC) <300 µg/L] and extremely excessive (UIC ≥ 2500 µg/L) iodine intake were associated with thyroid cancer in Korea, an iodine-replete area. Papillary thyroid cancer (PTC) accounts for more than 97 % of thyroid cancer and 80% or more PTC cases harbor the BRAF mutation in Korea. We aimed to investigate the relationship between iodine intake and the prevalence of the BRAF mutation in PTC in Korea. METHODS: UIC was measured by inductively coupled plasma mass spectrometry. The BRAF mutation was detected using both allele-specific polymerase chain reaction and mutant enrichment with 3'-modified oligonucleotide sequencing. Risk factors for the occurrence of BRAF mutations in PTC were evaluated using multivariate logistic regression models. RESULTS: The median UIC in all patients with PTC was 287 µg/L (range from 7 to 7, 426 µg/L). Nearly half of the patients (102/215, 47%) belonged to the excessive iodine intake category (UIC ≥ 300 µg/L) according to the WHO iodine recommendations. The frequency of BRAF mutations was lowest in the 300-499 µg/L UIC group; it was significantly different compared to the relatively low (UIC < 300 µg/L) and more than excessive (UIC ≥ 500 µg/L) iodine intake groups. UIC was an independent predictor for BRAF mutations in PTC. The multivariate-adjusted odds ratios (95% confidence intervals) in the relatively low and more than excessive iodine intake groups for the BRAF mutation were 4.761 (1.764-12.850) and 6.240 (2.080-18.726), respectively, compared to the 300-499 µg/L UIC group. CONCLUSION: Relatively low iodine intake and more than excessive iodine intake seem to be significant risk factors for the occurrence of BRAF mutations in the thyroid and, therefore, may be risk factors for the development of PTC in an iodine-replete area.

Linking resistin, inflammation, and cardiometabolic diseases.

Adipose tissue secretes a variety of bioactive substances that are associated with chronic inflammation, insulin resistance, and an increased risk of type 2 diabetes mellitus. While resistin was first known as an adipocyte-secreted hormone (adipokine) linked to obesity and insulin resistance in rodents, it is predominantly expressed and secreted by macrophages in humans. Epidemiological and genetic studies indicate that increased resistin levels are associated with the development of insulin resistance, diabetes, and cardiovascular disease. Resistin also appears to mediate the pathogenesis of atherosclerosis by promoting endothelial dysfunction, vascular smooth muscle cell proliferation, arterial inflammation, and the formation of foam cells. Thus, resistin is predictive of atherosclerosis and poor clinical outcomes in patients with cardiovascular disease and heart failure. Furthermore, recent evidence suggests that resistin is associated with atherogenic dyslipidemia and hypertension. The present review will focus on the role of human resistin in the pathogeneses of inflammation and obesity-related diseases.

Association of triiodothyronine levels with future development of metabolic syndrome in euthyroid middle-aged subjects: a 6-year retrospective longitudinal study.

BACKGROUND: Several cross-sectional studies have reported that thyroid hormone levels are associated with cardiovascular risk markers and metabolic syndrome (MetS) even in euthyroid subjects. However, the prognostic role of serum thyroid hormone levels in the risk of incident MetS has not been elucidated. AIM: We aimed to investigate the associations of baseline serum thyroid hormone levels with the development of MetS in healthy subjects. METHODS: This 6-year, cross-sectional, longitudinal and follow-up study was conducted in 12 037 euthyroid middle-aged subjects without MetS subjected to comprehensive health examinations. Subjects were grouped according to total triiodothyronine (T3) quartiles. The hazard ratio (HR) for the development of MetS according to T3 quartiles was estimated using Cox proportional hazards model. RESULTS: During the 6-year period, 3544 incident cases of MetS (29%) were identified. The proportion of subjects with incident MetS increased across the T3 quartiles (P for trend <0.001). The HR and 95% confidence interval (CI) for the development of MetS were significantly higher in the highest T3 quartile compared with the lowest T3 quartile even after adjusting for confounding variables including gender, age and smoking (HR: 1.238, 95% CI: 1.128-1.358, P < 0.001). CONCLUSION: In euthyroid middle-aged subjects, serum T3 levels are associated with increased risk for future development of MetS.

Strong association of relatively low and extremely excessive iodine intakes with thyroid cancer in an iodine-replete area.

PURPOSE: The relationship between iodine intake and development of thyroid diseases shows a U-shaped curve with an increase of risk in both deficient and excessive iodine intakes. Our aim was to investigate the relationship between iodine intake and thyroid cancer in patients with thyroid nodules in an iodine-replete area. METHODS: Retrospective analysis of 1170 patients with thyroid nodules was performed. Urinary iodine concentration (UIC) was measured by inductively-coupled plasma mass spectrometry. Predictive factors for thyroid cancer were evaluated using multivariate logistic regression models. RESULTS: The median UIC in all patients with thyroid nodules was 360 µg/L (range from 4 to 9631 µg/L). More than half of the patients (650/1170, 56 %) belonged to the category of excessive iodine intake (UIC ≥ 300 µg/L) according to WHO iodine recommendations. Patients with thyroid cancer were more likely to be distributed in UIC < 300 µg/L and in UIC ≥ 2500 µg/L than those with benign thyroid nodules. Male gender (OR 1.528, p = 0.028) and UIC were independent predictors for thyroid cancer. The multivariate-adjusted OR (95 % CI) in the relatively low (UIC < 300 µg/L) and extremely excessive (UIC ≥ 2500 µg/L) iodine intake groups for thyroid cancer were 1.519 (1.099-2.098) and 1.874 (1.094-3.208), respectively, compared to the other iodine intake group (300-2499 µg/L). CONCLUSION: Male gender and UIC were independent predictors of thyroid cancer in patients with thyroid nodules. This study suggests that relatively low and extremely excessive iodine intakes are associated with thyroid cancer in an iodine-replete area.

Case report of a bilateral adrenal myelolipoma associated with Cushing disease.

RATIONALE: Adrenal myelolipomas are rare benign tumors, composed of a variable mixture of mature adipose tissue and hematopoietic tissue. These tumors are frequently detected incidentally and are usually asymptomatic, and hormonally inactive. PATIENT CONCERNS: During a routine health checkup, a 52-year-old man was found to have a tumor on the bilateral adrenal glands. Abdominal computed tomography revealed a well-defined, heterogeneously enhanced bilateral adrenal mass, suggesting a myelolipoma. DIAGNOSES: The hormonal evaluation revealed adrenocorticotropic hormone (ACTH) dependent Cushing syndrome. INTERVENTIONS: The patient underwent left adrenalectomy, and transsphenoidal resection of a pituitary mass. The final diagnosis was adrenal myelolipoma associated with Cushing disease. OUTCOMES: Growth of right adrenal myelolipoma was detected during the 7-year follow-up. There were enhancing pituitary lesions in repeat magnetic resonance imaging of the sellar region, which implies persistent or recurrent pituitary adenoma. This case reinforces relationship between Cushing disease and adrenal myelolipoma. LESSONS: To the best of our knowledge, this is the first reported pathologically confirmed bilateral adrenal myelolipoma associated with Cushing disease. This report supports the idea that ACTH is associated with the development of adrenal myelolipoma.