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.

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 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.

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.

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.

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.

Preoperative serum thyroglobulin and changes in serum thyroglobulin during TSH suppression independently predict follicular thyroid carcinoma in thyroid nodules with a cytological diagnosis of follicular lesion.

BACKGROUND: Fine-needle aspiration biopsy (FNAB) cannot distinguish a follicular thyroid carcinoma (FTC) from a follicular adenoma in follicular lesions. We designed this study to determine whether the preoperative thyroglobulin (Tg) and change in serum Tg during thyroid-stimulating hormone (TSH) suppression can predict FTC in thyroid nodules with a cytological diagnosis of follicular lesion. METHODS: Among 854 patients who underwent thyroid surgery, the 198 patients who presented with thyroid nodules with a cytological diagnosis of follicular lesion were analyzed. Predictive factors for malignancy were evaluated using multivariate logistic regression models. Subgroup analyses of patients with TSH suppression therapy by levothyroxine were also conducted. RESULTS: Thirty-two patients (16%) had FTC, and 166 patients had confirmed benign nodules. The median preoperative serum Tg levels were significantly higher in patients with FTC compared to those with benign pathology (449 vs. 34 ng/mL, p < 0.001). The serum Tg (odds ratios (OR) 10.311, p < 0.001) and tumor volume (OR 4.500, p = 0.035) were found to be independent predictors for FTC in all patients with a cytological diagnosis of follicular lesion. Forty-eight patients received TSH suppression therapy. When we performed subgroup analyses on the patients with TSH suppression therapy, decrease less than 15% in serum Tg during TSH suppression was found to be an independent predictor of FTC (OR 13.918, p = 0.018). CONCLUSION: Preoperative serum Tg and changes in serum Tg during TSH suppression independently predict FTC in thyroid nodules with a cytological diagnosis of follicular lesion.

Association of free thyroxine with obstructive lung pattern in euthyroid middle-aged subjects: A population-based study.

BACKGROUND: The association between thyroid hormone levels and pulmonary function in euthyroid population is still unclear. We aimed to examine the relationship between thyroid function and lung function in a large cohort study of euthyroid subjects. METHODS: We analyzed biochemical and spirometry data from a nationwide, population-based, cross-sectional survey (KNHANES VI). A total of 1,261 middle-aged participants aged 45-65 years with spirometry tests and normal thyroid function were included in this study. The subjects were grouped according to free thyroxine (fT4) (ng/dL) quartiles (Q1, 0.89-1.09; Q2, 1.10-1.19; Q3, 1.20-1.30; Q4, 1.31-1.76). Obstructive lung pattern was defined as forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) <0.7. The probability of obstructive lung patterns according to fT4 quartiles was assessed using logistic regression models, adjusted for potential confounders. RESULTS: Overall, 10.9% of the subjects had an obstructive lung pattern. The mean fT4 levels were significantly higher in those with obstructive lung pattern than in those with normal lung function (1.26 vs. 1.20 ng/dL, p<0.001). The proportion of participants with obstructive lung pattern increased across the fT4 quartile categories (p<0.001). With the Q1 group as reference, the multivariate-adjusted odds ratios (95% confidence intervals) for obstructive lung pattern in the Q3 and Q4 groups were 2.875 (1.265-6.535) and 2.970 (1.287-6.854), respectively, even after adjusting for confounding variables. CONCLUSION: High fT4 levels are an independent predictor of obstructive lung pattern in euthyroid middle-aged subjects. Further prospective studies are needed to confirm these findings.

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.

Empagliflozin suppresses urinary mitochondrial DNA copy numbers and interleukin-1ß in type 2 diabetes patients.

Sodium-glucose co-transporter 2 (SGLT2) inhibitors improve cardiovascular and renal outcomes in type 2 diabetes mellitus (T2DM) patients. However, the mechanisms by which SGLT2 inhibitors improve the clinical outcomes remain elusive. We evaluated whether empagliflozin, an SGLT2 inhibitor, ameliorates mitochondrial dysfunction and inflammatory milieu of the kidneys in T2DM patients. We prospectively measured copy numbers of urinary and serum mitochondrial DNA (mtDNA) nicotinamide adenine dinucleotide dehydrogenase subunit-1 (mtND-1) and cytochrome-c oxidase 3 (mtCOX-3) and urinary interleukin-1ß (IL-1ß) in healthy volunteers (n = 22), in SGLT2 inhibitor-naïve T2DM patients (n = 21) at baseline, and in T2DM patients after 3 months of treatment with empagliflozin (10 mg, n = 17 or 25 mg, n = 4). Both urinary mtDNA copy numbers and IL-1ß levels were higher in the T2DM group than in healthy volunteers. Baseline copy numbers of serum mtCOX-3 in the T2DM group were lower than those in healthy volunteers. Empagliflozin induced marked reduction in both urinary and serum mtND-1 and mtCOX-3 copy numbers, as well as in urinary IL-1ß. Empagliflozin could attenuate mitochondrial damage and inhibit inflammatory response in T2DM patients. This would explain the beneficial effects of SGLT2 inhibitors on cardiovascular and renal outcomes.

Association between subclinical hypothyroidism and severe diabetic retinopathy in Korean patients with type 2 diabetes.

The association between subclinical hypothyroidism (SCH) and microvascular complications of type 2 diabetes is unclear. We examined whether SCH is associated with diabetic retinopathy or nephropathy in Korean patients with type 2 diabetes. Data from 489 patients who visited the diabetes clinic at a university hospital between 2001 and 2007 were analyzed retrospectively. Participants were evaluated for glycemic control, thyroid function, and diabetic retinopathy and nephropathy. Diabetic retinopathy was classified into five grades. Diabetic nephropathy was assessed by the presence of albuminuria. Patients in the SCH group had a higher proportion of women, older age, longer duration of diabetes, higher systolic and diastolic blood pressure, and higher insulin resistance index compared with the euthyroid group. No significant difference in family history of diabetes or body mass index was found between groups. The prevalence of severe diabetic retinopathy (severe nonproliferative diabetic retinopathy or proliferative diabetic retinopathy) was significantly higher in the SCH group than the euthyroid group (32.8% vs. 19.6%, P = 0.036), whereas no between-group difference was found in the prevalence of diabetic nephropathy. After adjustment for potential confounding factors (HbA1c, BMI, duration of diabetes, diabetic nephropathy, and hypertension) by multivariate logistic regression analysis, SCH remained significantly associated with severe diabetic retinopathy (odds ratio 2.086 (95% CI, 1.010-4.307), P = 0.047). These results suggest that SCH was independently associated with severe diabetic retinopathy in patients with type 2 diabetes. Further prospective studies are required to confirm the association between SCH and diabetic retinopathy.

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.

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.

Association between Sarcopenia, Sarcopenic Obesity, and Chronic Disease in Korean Elderly.

BACKGROUND: It is a very important social issue for Korea to have a healthy old age as an aged society. Aging causes a lot of physical changes, especially sarcopenia. Sarcopenia is defined as a persistent decrease in skeletal muscle and muscle strength. Sarcopenic obesity is a phenomenon in which fat is replaced instead of muscle. The purpose of this study was to examine the prevalence of sarcopenia and sarcopenic obesity in Korean elderly and to analyze the relationship with chronic disease. METHODS: Data from the 2008 to 2011 the Korea National Health and Nutrition Survey were used. A total of 3,492 patients were classified into 3 groups (non-sarcopenia, sarcopenia, sarcopenic obesity), and general, anthropometry, health behavior, nutrient intake and chronic disease status were compared by the statistical analysis. RESULTS: The rate of moderate exercise was significantly lower in the sarcopenia and sarcopenic-obesity group than in the non-sarcopenia group (P=0.007). The sarcopenic obesity group had significantly higher energy (P=0.005), protein (P=0.046) and fat (P=0.001) intake than the sarcopenic group. The sarcopenic-obesity group had the highest ratio of diabetes (P=0.023) and dyslipidemia (P=0.004) in the 3 groups. Compared with the non-sarcopenia group, in the sarcopenia and sarcopenic obesity groups, the odds ratios (ORs) of diabetes was increased by 1.24 and 2.16 while the ORs of dyslipidemia was increased by 1.12 and 1.50, respectively. CONCLUSIONS: Regular exercise and adequate nutrient intake (energy, protein and fat) are essential for the prevention of sarcopenia in Korean elderly, and management of chronic disease in sarcopenic obesity elderly is important.

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.

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.

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.