Survival Comparison of Incidentally Found versus Clinically Detected Thyroid Cancers: An Analysis of a Nationwide Cohort Study

Background@#The true benefit of thyroid cancer screening is incompletely understood. This study investigated the impact of ultrasound screening on thyroid cancer outcomes through a comparison with symptomatic thyroid cancer using data from a nationwide cohort study in Korea. @*Methods@#Cox regression analysis was performed to assess the hazard ratios (HRs) for all-cause and thyroid cancer-specific mortality. Considering the possible bias arising from age, sex, year of thyroid cancer registration, and confounding factors for mortality (including smoking/drinking status, diabetes, and hypertension), all analyses were conducted with stabilized inverse probability of treatment weighting (IPTW) according to the route of detection. @*Results@#Of 5,796 patients with thyroid cancer, 4,145 were included and 1,651 were excluded due to insufficient data. In comparison with the screening group, the clinical suspicion group was associated with large tumors (17.2±14.6 mm vs. 10.4±7.9 mm), advanced T stage (3–4) (odds ratio [OR], 1.24; 95% confidence interval [CI], 1.09 to 1.41), extrathyroidal extension (OR, 1.16; 95% CI, 1.02 to 1.32), and advanced stage (III–IV) (OR, 1.16; 95% CI, 1.00 to 1.35). In IPTW-adjusted Cox regression analysis, the clinical suspicion group had significantly higher risks of all-cause mortality (HR, 1.43; 95% CI, 1.14 to 1.80) and thyroid cancer-specific mortality (HR, 3.07; 95% CI, 1.77 to 5.29). Mediation analysis showed that the presence of thyroid-specific symptoms was directly associated with a higher risk of cancer-specific mortality. Thyroid-specific symptoms also indirectly affected thyroid cancer-specific mortality, mediated by tumor size and advanced clinicopathologic status. @*Conclusion@#Our findings provide important evidence for the survival benefit of early detection of thyroid cancer compared to symptomatic thyroid cancer.

Lower Thyroid Cancer Mortality in Patients Detected by Screening: A Meta-Analysis

Background@#Thyroid cancer screening has contributed to the skyrocketing prevalence of thyroid cancer. However, the true benefit of thyroid cancer screening is not fully understood. This study aimed to evaluate the impact of screening on the clinical outcomes of thyroid cancer by comparing incidental thyroid cancer (ITC) with non-incidental thyroid cancer (NITC) through a meta-analysis. @*Methods@#PubMed and Embase were searched from inception to September 2022. We estimated and compared the prevalence of high-risk features (aggressive histology of thyroid cancer, extrathyroidal extension, metastasis to regional lymph nodes or distant organs, and advanced tumor-node-metastasis [TNM] stage), thyroid cancer-specific death, and recurrence in the ITC and NITC groups. We also calculated pooled risks and 95% confidence intervals (CIs) of the outcomes derived from these two groups. @*Results@#From 1,078 studies screened, 14 were included. In comparison to NITC, the ITC group had a lower incidence of aggressive histology (odds ratio [OR], 0.46; 95% CI, 0.31 to 0.7), smaller tumors (mean difference, −7.9 mm; 95% CI, −10.2 to −5.6), lymph node metastasis (OR, 0.64; 95% CI, 0.48 to 0.86), and distant metastasis (OR, 0.42; 95% CI, 0.23 to 0.77). The risks of recurrence and thyroid cancer-specific mortality were also lower in the ITC group (OR, 0.42; 95% CI, 0.25 to 0.71 and OR, 0.46; 95% CI, 0.28 to 0.74) than in the NITC group. @*Conclusion@#Our findings provide important evidence of a survival benefit from the early detection of thyroid cancer compared to symptomatic thyroid cancer.

Associations of Phthalate Metabolites and Bisphenol A Levels with Obesity in Children: The Korean National Environmental Health Survey (KoNEHS) 2015 to 2017

Phthalates and bisphenol A (BPA) are synthetic chemicals widely used in daily life. This study investigated urinary phthalate and BPA levels in Korean children and their associations with obesity. Methods: A total of 2,351 children aged 3 to 17 years who participated in the Korean National Environmental Health Survey 2015 to 2017 were included. Urinary dilution was corrected using covariate-adjusted standardization (CAS). We examined the geometric mean (GM) concentrations of urinary phthalate metabolites, including di (2-ethylhexyl) phthalate (DEHP) metabolites (mono [2-ethyl-5-hydroxyhexyl] phthalate, mono [2-ethyl-5-oxohexyl] phthalate, and mono [2-ethyl-5-carboxypentyl] phthalate [MECPP]), mono-benzyl-phthalate (MBzP), mono (carboxyoctyl) phthalate (MCOP), mono (carboxy-isononyl) phthalate (MCNP), mono (3-carboxypropyl) phthalate, and mono-n-butyl-phthalate (MnBP), and BPA. We also analyzed the odds ratio (OR) for obesity according to the quartiles of each analyte. Results: The urinary GM levels of DEHP metabolites and MnBP were notably higher among Korean children than among American, Canadian, and German children. The CAS-applied GM concentrations of most analytes, except for MBzP, MCOP, and MCNP, were higher in children aged 3 to 5 years than in those aged 6 to 17 years. The OR for obesity in the highest quartile of MECPP was significantly higher than in the lowest quartile after adjusting for covariates. However, the other phthalate metabolites and BPA were not significantly associated with obesity. Conclusion: The concentrations of urinary DEHP metabolites and MnBP were higher in Korean children than in children in Western countries. Urinary MECPP exposure, but not other phthalates or BPA, showed a positive association with obesity in Korean children. Further studies are required to elucidate the causal relationships.

The Relationship Between Nocturia and Mortality: Data From the National Health and Nutrition Examination Survey / 대한배뇨장애요실금학회지

Purpose@#We investigated the relationship between nocturia and mortality risk in the United States. @*Methods@#Data were obtained from the National Health and Nutrition Examination Survey 2005–2010. Mortality data were obtained by linking the primary database to death certificate data found in the National Death Index with mortality follow-up up to December 31, 2015. Nocturia was defined based on symptoms reported in the symptom questionnaire. We categorized patients into 2 groups: mild nocturia (2–3 voidsight) and moderate-to severe nocturia (≥4 voidsight). Multiple Cox regression analyses were performed with adjustment for confounding variables at the baseline survey. @*Results@#This study included 9,892 adults (4,758 men, 5,134 women). Nocturia occurred in 3,314 individuals (33.5%). Nocturia was significantly associated with all-cause mortality (hazard ratio [HR], 1.23; 95% confidence interval [CI], 1.10–1.39) and cardiovascular disease (CVD) mortality (HR, 1.55; 95% CI, 1.19–2.01). Moreover, the mortality risk increased with increasing nocturia severity. Further analysis with propensity score matching showed that nocturia was still significantly associated with all-cause mortality and CVD mortality. In subgroup analysis according to sex, nocturia was significantly associated with allcause mortality and CVD mortality in men. In women, moderate-to-severe nocturia was significantly associated with allcause mortality and CVD mortality. In subgroup analysis according to cardio-metabolic diseases, nocturia was associated with CVD mortality in patients with diabetes mellitus, hypertension, dyslipidemia, or CVD at baseline. In subgroup analysis of patients without diabetes mellitus, hypertension or CVD, nocturia was significantly associated with all-cause mortality. @*Conclusions@#Nocturia was significantly associated with mortality in men and women after adjusting for major confounding factors.

Efficacy and Safety of the New Appetite Suppressant, Liraglutide: A Meta-Analysis of Randomized Controlled Trials

Background@#Obesity is a chronic disease associated with metabolic diseases such as diabetes and cardiovascular disease. Since the U.S. Food and Drug Administration approved liraglutide as an anti-obesity drug for nondiabetic patients in 2014, it has been widely used for weight control in overweight and obese people. This study aimed to systematically analyze the effects of liraglutide on body weight and other cardiometabolic parameters. @*Methods@#We investigated articles from PubMed, EMBASE, and the Cochrane Library to search randomized clinical trials that examined body weight changes with liraglutide treatment. @*Results@#We included 31 studies with 8,060 participants for this meta-analysis. The mean difference (MD) between the liraglutide group and the placebo group was −4.19 kg (95% confidence interval [CI], −4.84 to −3.55), with a −4.16% change from the baseline (95% CI, −4.90 to −3.43). Liraglutide treatment correlated with a significantly reduced body mass index (MD: −1.55; 95% CI, −1.76 to −1.34) and waist circumference (MD: −3.11 cm; 95% CI, −3.59 to −2.62) and significantly decreased blood pressure (systolic blood pressure, MD: −2.85 mm Hg; 95% CI, −3.36 to −2.35; diastolic blood pressure, MD: −0.66 mm Hg; 95% CI, −1.02 to −0.30), glycated hemoglobin (MD: −0.40%; 95% CI, −0.49 to −0.31), and low-density lipoprotein cholesterol (MD: –2.91 mg/dL; 95% CI, −5.28 to −0.53; MD: −0.87% change from baseline; 95% CI, −1.17 to −0.56). @*Conclusion@#Liraglutide is effective for weight control and can be a promising drug for cardiovascular protection in overweight and obese people.

Effect of Sarcopenia and Body Shape on Cardiovascular Disease According to Obesity Phenotypes

BackgroundThis study aimed to assess the effects of sarcopenia and A Body Shape Index (ABSI) on cardiovascular disease (CVD) risk according to obesity phenotypes.MethodsWe used data from the National Health and Nutrition Examination Survey 1999 to 2012. A total of 25,270 adults were included and classified into the following groups: metabolically healthy normal weight (MHNW), metabolically healthy overweight/obese (MHO), metabolically unhealthy normal weight (MUNW), and metabolically unhealthy overweight/obese (MUO). Sarcopenia was defined as the appendicular skeletal mass index ResultsThe MHNW participants with sarcopenia had higher risk for CVD than those without sarcopenia (OR, 2.69; 95% confidence interval [CI], 1.56 to 4.64). In the analysis with MHNW participants without sarcopenia as a reference, the participants with sarcopenia showed a higher OR for CVD than those without sarcopenia in both MHO (OR in participants without sarcopenia, 3.31; 95% CI, 1.94 to 5.64) (OR in participants with sarcopenia, 8.59; 95% CI, 2.63 to 28.04) and MUO participants (OR in participants without sarcopenia, 5.11; 95% CI, 3.21 to 8.15) (OR in participants with sarcopenia, 8.12; 95% CI, 4.04 to 16.32). Participants within the second and third tertiles of ABSI had higher ORs for CVDs than the counterpart of obesity phenotypes within the first tertile.ConclusionThese results suggest that clinical approaches that consider muscle and body shape are required.

Efficacy and Safety of the New Appetite Suppressant, Liraglutide: A Meta-Analysis of Randomized Controlled Trials

Background@#Obesity is a chronic disease associated with metabolic diseases such as diabetes and cardiovascular disease. Since the U.S. Food and Drug Administration approved liraglutide as an anti-obesity drug for nondiabetic patients in 2014, it has been widely used for weight control in overweight and obese people. This study aimed to systematically analyze the effects of liraglutide on body weight and other cardiometabolic parameters. @*Methods@#We investigated articles from PubMed, EMBASE, and the Cochrane Library to search randomized clinical trials that examined body weight changes with liraglutide treatment. @*Results@#We included 31 studies with 8,060 participants for this meta-analysis. The mean difference (MD) between the liraglutide group and the placebo group was −4.19 kg (95% confidence interval [CI], −4.84 to −3.55), with a −4.16% change from the baseline (95% CI, −4.90 to −3.43). Liraglutide treatment correlated with a significantly reduced body mass index (MD: −1.55; 95% CI, −1.76 to −1.34) and waist circumference (MD: −3.11 cm; 95% CI, −3.59 to −2.62) and significantly decreased blood pressure (systolic blood pressure, MD: −2.85 mm Hg; 95% CI, −3.36 to −2.35; diastolic blood pressure, MD: −0.66 mm Hg; 95% CI, −1.02 to −0.30), glycated hemoglobin (MD: −0.40%; 95% CI, −0.49 to −0.31), and low-density lipoprotein cholesterol (MD: –2.91 mg/dL; 95% CI, −5.28 to −0.53; MD: −0.87% change from baseline; 95% CI, −1.17 to −0.56). @*Conclusion@#Liraglutide is effective for weight control and can be a promising drug for cardiovascular protection in overweight and obese people.

Effect of Sarcopenia and Body Shape on Cardiovascular Disease According to Obesity Phenotypes

BackgroundThis study aimed to assess the effects of sarcopenia and A Body Shape Index (ABSI) on cardiovascular disease (CVD) risk according to obesity phenotypes.MethodsWe used data from the National Health and Nutrition Examination Survey 1999 to 2012. A total of 25,270 adults were included and classified into the following groups: metabolically healthy normal weight (MHNW), metabolically healthy overweight/obese (MHO), metabolically unhealthy normal weight (MUNW), and metabolically unhealthy overweight/obese (MUO). Sarcopenia was defined as the appendicular skeletal mass index ResultsThe MHNW participants with sarcopenia had higher risk for CVD than those without sarcopenia (OR, 2.69; 95% confidence interval [CI], 1.56 to 4.64). In the analysis with MHNW participants without sarcopenia as a reference, the participants with sarcopenia showed a higher OR for CVD than those without sarcopenia in both MHO (OR in participants without sarcopenia, 3.31; 95% CI, 1.94 to 5.64) (OR in participants with sarcopenia, 8.59; 95% CI, 2.63 to 28.04) and MUO participants (OR in participants without sarcopenia, 5.11; 95% CI, 3.21 to 8.15) (OR in participants with sarcopenia, 8.12; 95% CI, 4.04 to 16.32). Participants within the second and third tertiles of ABSI had higher ORs for CVDs than the counterpart of obesity phenotypes within the first tertile.ConclusionThese results suggest that clinical approaches that consider muscle and body shape are required.

Effect of Multiple Exposure to Perfluorinated Chemicals on Thyroid Function among Adults in the US: The National Health and Nutrition Examination Survey 2007-2008 and 2011-2012

Background and Objectives@#Perfluoroalkyl substances (PFASs) are known to disrupt the thyroid hormone system. However, no study has assessed the association between multiple exposure to PFASs and the thyroid hormone system. This study aimed to identify the singular effects of each PFAS and the effects of multiple exposure to PFASs on the thyroid hormone profile in a representative sample of the US population. @*Materials and Methods@#We used data from the US National Health and Nutrition Examination Survey (NHANES) 2007-2008 and 2011-2012. To assess the effect of simultaneous exposure to multiple PFASs on thyroid function, principal component (PC) analysis with varimax rotation was performed. Multivariate linear regression analysis was conducted to identify the effect of each PFAS and PC on thyroid function. @*Results@#In this study, perfluorooctanoate (PFOA) was associated with a decrease in total T4 and Free T4 levels. Perfluorooctane sulfonate (PFOS) was associated with a decrease in total T4 level and perfluorononanoate (PFNA) and perfluorodecanoate (PFDeA) were associated with decreases in TSH levels. In PC analysis, two PCs were identified. PC1 included PFOA, PFOS, perfluorohexane sulfonate (PFHxS), PFNA and 2-(N-methyl-perfluorooctane sulfonamido) acetic acid with high loading. PC2 included PFNA, PFDeA, and perfluoroundecanoate (PFUA). In the multivariate linear regression analysis, PC1 showed negative correlations with total T4 and Free T4 levels, whereas PC2 showed a negative correlation with TSH level. @*Conclusion@#We found that singular and multiple exposure to PFASs was associated with a disruption in thyroid hormone system.

Effect of Sarcopenia and Body Shape on Cardiovascular Disease According to Obesity Phenotypes

Background@#This study aimed to assess the effects of sarcopenia and A Body Shape Index (ABSI) on cardiovascular disease (CVD) risk according to obesity phenotypes. @*Methods@#We used data from the National Health and Nutrition Examination Survey 1999 to 2012. A total of 25,270 adults were included and classified into the following groups: metabolically healthy normal weight (MHNW), metabolically healthy overweight/obese (MHO), metabolically unhealthy normal weight (MUNW), and metabolically unhealthy overweight/obese (MUO). Sarcopenia was defined as the appendicular skeletal mass index <7 kg/m2 in men and <5.5 kg/m2 in women. A multivariate logistic regression analysis was performed to evaluate the odds ratio (OR) of sarcopenia and ABSI for CVD events according to the obesity phenotype. @*Results@#The MHNW participants with sarcopenia had higher risk for CVD than those without sarcopenia (OR, 2.69; 95% confidence interval [CI], 1.56 to 4.64). In the analysis with MHNW participants without sarcopenia as a reference, the participants with sarcopenia showed a higher OR for CVD than those without sarcopenia in both MHO (OR in participants without sarcopenia, 3.31; 95% CI, 1.94 to 5.64) (OR in participants with sarcopenia, 8.59; 95% CI, 2.63 to 28.04) and MUO participants (OR in participants without sarcopenia, 5.11; 95% CI, 3.21 to 8.15) (OR in participants with sarcopenia, 8.12; 95% CI, 4.04 to 16.32). Participants within the second and third tertiles of ABSI had higher ORs for CVDs than the counterpart of obesity phenotypes within the first tertile. @*Conclusion@#These results suggest that clinical approaches that consider muscle and body shape are required.

The Association Between Obesity and the Nocturia in the U.S. Population / 대한배뇨장애요실금학회지

PURPOSE: We aimed to investigate the association of obesity with nocturia using a nationally representative sample of adults from the National Health and Nutrition Examination Survey (NHANES) between 2005 and 2012. METHODS: A total of 14,135 participants were included in this study. We performed a multivariate logistic regression analysis to find the odds ratio (OR) of obesity for nocturia. Furthermore, the OR of BMI for nocturia was analyzed using restricted cubic splines (RCS) with five knots. We conducted subgroup analysis according to age, sex, hypertension, and diabetes mellitus (DM) and further analysis with 1:1 matching data with propensity score. RESULTS: The participants who had body mass index (BMI) above 30 kg/m² had a significantly higher OR for nocturia (OR, 1.39; 95% CI, 1.28–1.50) than those without obesity. RCS showed a dose-dependent relationship between BMI and OR for nocturia. Subgroup analysis by age, sex, hypertension, and DM showed similar results. Further analysis with 1:1 matching data showed a significant association of obesity with the prevalence of nocturia (OR, 1.25; 95% CI, 1.10–1.41). CONCLUSIONS: This study reported that obesity was significant association with the prevalence of nocturia with dose-dependent manner, regardless of age, sex, hypertension, and DM after taking major confounding factors into account.

The Association between Z-Score of Log-Transformed A Body Shape Index and Cardiovascular Disease in Korea

BACKGROUND: In order to overcome the limitations of body mass index (BMI) and waist circumference (WC), the z-score of the log-transformed A Body Shape Index (LBSIZ) has recently been introduced. In this study, we analyzed the relationship between the LBSIZ and cardiovascular disease (CVD) in a Korean representative sample. METHODS: Data were collected from the Korea National Health and Nutrition Examination VI to V. The association between CVD and obesity indices was analyzed using a receiver operating characteristic curve. The cut-off value for the LBSIZ was estimated using the Youden index, and the odds ratio (OR) for CVD was determined via multivariate logistic regression analysis. ORs according to the LBSIZ value were analyzed using restricted cubic spline regression plots. RESULTS: A total of 31,227 Korean healthy adults were analyzed. Area under the curve (AUC) of LBSIZ against CVD was 0.686 (95% confidence interval [CI], 0.671 to 0.702), which was significantly higher than the AUC of BMI (0.583; 95% CI, 0.567 to 0.599) or WC (0.646; 95% CI, 0.631 to 0.661) (P<0.001). Similar results were observed for stroke and coronary artery diseases. The cut-off value for the LBSIZ was 0.35 (sensitivity, 64.5%; specificity, 64%; OR, 1.29, 95% CI, 1.12 to 1.49). Under restricted cubic spline regression, LBSIZ demonstrated that OR started to increase past the median value. CONCLUSION: The findings of this study suggest that the LBSIZ might be more strongly associated with CVD risks compared to BMI or WC. These outcomes would be helpful for CVD risk assessment in clinical settings, especially the cut-off value of the LBSIZ suggested in this study.

Association between Serum Selenium Level and the Presence of Diabetes Mellitus: A Meta-Analysis of Observational Studies

BACKGROUND: Epidemiological studies have suggested an association between selenium (Se) and diabetes mellitus (DM). However, different studies have reported conflicting results. Therefore, we performed a comprehensive meta-analysis to clarify the impact of Se on DM. METHODS: We searched the PubMed database for studies on the association between Se and DM from inception to June 2018. RESULTS: Twenty articles evaluating 47,930 participants were included in the analysis. The meta-analysis found that high levels of Se were significantly associated with the presence of DM (pooled odds ratios [ORs], 1.88; 95% confidence interval [CI], 1.44 to 2.45). However, significant heterogeneity was found (I2 =82%). Subgroup analyses were performed based on the Se measurement methods used in each study. A significant association was found between high Se levels and the presence of DM in the studies that used blood (OR, 2.17; 95% CI, 1.60 to 2.93; I2 =77%), diet (OR, 1.61; 95% CI, 1.10 to 2.36; I2 =0%), and urine (OR, 1.49; 95% CI, 1.02 to 2.17; I2 =0%) as samples to estimate Se levels, but not in studies on nails (OR, 1.24; 95% CI, 0.52 to 2.98; I2 =91%). Because of significant heterogeneity in the studies with blood, we conducted a sensitivity analysis and tested the publication bias. The results were consistent after adjustment based on the sensitivity analysis as well as the trim and fill analysis for publication bias. CONCLUSION: This meta-analysis demonstrates that high levels of Se are associated with the presence of DM. Further prospective and randomized controlled trials are warranted to elucidate the link better.

The Cut-off Values of Surrogate Measures for Insulin Sensitivity in a Healthy Population in Korea according to the Korean National Health and Nutrition Examination Survey (KNHANES) 2007–2010

BACKGROUND: This study aimed to identify the gender-specific characteristics of the surrogate measures of insulin resistance and to establish valid cut-off values for metabolic abnormalities in a representative sample in Korea. METHODS: Data were collected from the datasets of the Korean National Health and Nutrition Examination Survey between 2007 and 2010. The total number of eligible participants was 10,997. We used three measures of insulin resistance: the homeostasis model assessment-insulin resistance (HOMA-IR), McAuley index, and triglyceride and glucose (TyG) index. The estimated cut-off values were determined using the highest score of the Youden index. RESULTS: The area under the curve (AUC) of the HOMA-IR, McAuley index, and TyG index were 0.737 (95% confidence interval [CI], 0.725–0.750), 0.861 (95% CI, 0.853–0.870), and 0.877 (95% CI, 0.868–0.885), respectively. The cut-off values of the HOMA-IR were 2.20 in men, 2.55 in premenopausal women, and 2.03 in postmenopausal women, and those of the McAuley index were 6.4 in men and 6.6 in premenopausal and postmenopausal women. For the TyG index, the cut-off values were 4.76 in men and 4.71 in premenopausal and postmenopausal women. CONCLUSION: In conclusion, the present study provides the valid cut-off values of the indirect surrogate measures of insulin sensitivity. These values may be used as reference for insulin sensitivity in a clinical setting and may provide a simple and supplementary method for identifying populations at risk of insulin resistance.

Star-Shaped Intense Uptake of ¹³¹I on Whole Body Scans Can Reflect Good Therapeutic Effects of Low-Dose Radioactive Iodine Treatment of 1.1 GBq

BACKGROUND: After initial radioactive iodine (RAI) treatment in differentiated thyroid cancer patients, we sometimes observe a star-shaped region of intense uptake of 131I on whole body scans (WBSs), called a ‘star artifact.’ We evaluated the clinical implications of star artifacts on the success rate of remnant ablation and long-term prognosis. METHODS: Total 636 patients who received 131I dose of 1.1 GBq for the initial RAI therapy and who did not show distant metastasis at the time of diagnosis were retrospectively evaluated. A negative second WBS was used for evaluating the ablation efficacy of the RAI therapy. Among them, 235 patients (36.9%) showed a star artifact on their first WBS. RESULTS: In patients with first stimulated thyroglobulin (sTg) levels ≤2 ng/mL, patients with star artifacts had a higher rate of negative second WBS compared with those without star artifacts (77.8% vs. 63.9%, P=0.044), and showed significantly higher recurrence-free survival (P=0.043) during the median 8.0 years (range, 1.0 to 10.0) of follow-up. The 5- and 10-year recurrence rates (5YRR, 10YRR) were also significantly lower in patients with star artifacts compared with those without (0% vs. 4.9%, respectively, P=0.006 for 5YRR; 0% vs. 6.4%, respectively, P=0.005 for 10YRR). However, ablation success rate or recurrence-free survival was not different among patients whose first sTg levels >2 ng/mL regardless of star artifacts. CONCLUSION: Therefore, star artifacts at initial RAI therapy imply a good ablation efficacy or a favorable long-term prognosis in patients with sTg levels ≤2 ng/mL.

Associations between Hashimoto Thyroiditis and Clinical Outcomes of Papillary Thyroid Cancer: A Meta-Analysis of Observational Studies

BACKGROUND: Epidemiological studies have suggested an association between Hashimoto thyroiditis (HT) and papillary thyroid cancer (PTC) development. Other studies, however, have reported a protective role of HT against PTC progression. Through this updated meta-analysis, we aimed to clarify the effects of HT on the progression of PTC. METHODS: We searched citation databases, including PubMed and Embase, for relevant studies from inception to September 2017. From these studies, we calculated the pooled odds ratios (ORs) of clinicopathologic features and the relative risk (RR) of PTC recurrence with 95% confidence intervals (CIs) using the Mantel-Haenszel method. Additionally, the Higgins I 2 statistic was used to test for heterogeneity. RESULTS: The meta-analysis included 71 published studies with 44,034 participants, among whom 11,132 had HT. We observed negative associations between PTC with comorbid HT and extrathyroidal extension (OR, 0.74; 95% CI, 0.68 to 0.81), lymph node metastasis (OR, 0.82; 95% CI, 0.72 to 0.94), distant metastasis (OR, 0.49; 95% CI, 0.32 to 0.76), and recurrence (RR, 0.50; 95% CI, 0.41 to 0.61). CONCLUSION: In this meta-analysis, PTC patients with HT appeared to exhibit more favorable clinicopathologic characteristics and a better prognosis than those without HT.

The Cut-off Values of Triglycerides and Glucose Index for Metabolic Syndrome in American and Korean Adolescents

The aim of this study was to establish ethnic- and gender-specific cut-off values of triglycerides and glucose index (TyG index) for clinical usefulness in a representative sample of Mexican American, Non-Hispanic White, Non-Hispanic Black, and Korean adolescents. The data were collected from datasets of the National Health and Nutrition Examination Survey between 1999 and 2012, and the Korean National Health and Nutrition Examination Survey between 2005 and 2013. Receiver operating characteristic curve analysis was used to find valid cut-off values of the TyG index for metabolic syndrome. The total number of eligible participants was 3,164 in the US and 4,873 in Korea. The optimal cut-off value with the Cook et al. definition revealed 8.55 in Mexican American, 8.55 in Non-Hispanic White, 8.35 in Non-Hispanic Black, and 8.45 in Korean, respectively. The cut-off value with the de Ferranti et al. definition was 8.45, 8.45, 8.15, and 8.35, and the cut-off value with the International Diabetes Federation definition was 8.65, 8.65, 8.15, and 8.55, respectively. These findings may be clinically useful for evaluating insulin resistance for determining metabolic abnormalities in adolescents.

Hepatitis A in Korea from 2011 to 2013: Current Epidemiologic Status and Regional Distribution

The hepatitis A virus (HAV) has been the leading cause of viral hepatitis in Korea since the 2000s. We aimed to describe the current status and regional differences in hepatitis A incidence. We studied the total number of hepatitis A cases reported to the Korea Centers for Disease Control and Prevention through the National Infectious Diseases Surveillance System between 2011 and 2013. Additionally, National Health Insurance Review and Assessment Service data and national population data from Statistics Korea were used. In total, 7,585 hepatitis A cases were reported; 5,521 (10.9 cases per 100,000 populations), 1,197 (2.3 cases per 100,000 populations), and 867 (1.7 cases per 100,000 populations) in 2011, 2012, and 2013, respectively. Fifty-eight patients were infected outside of the country and 7,527 patients represented autochthonous HAV infection cases. Autochthonous HAV infection occurred more frequently among men than women (4,619 cases, 6.1 cases per 100,000 population vs. 2,908 cases, 3.9 cases per 100,000 population). The incidence rate was higher in the 20-29 yr-old group (2,309 cases, 11.6 cases per 100,000 populations) and 30-39 yr-old group (3,306 cases, 13.6 cases per 100,000 populations). The majority of cases were reported from March to June (53.6%, 4,038/7,527). Geographic analyses revealed a consistently high relative risk (RR) of HAV infection in mid-western regions (2011, RR, 1.25, P=0.019; 2012, RR, 2.53, P<0.001; 2013, RR, 1.86, P<0.001). In summary, we report that hepatitis A incidence has been decreasing gradually from 2011 to 2013 and that some regions show the highest prevalence rates of HAV infection in Korea.

Erratum: Addition of a Co-Author

The authors regret that one co-author was missing in the article.

Epidemiological Characteristics of the First Water-Borne Outbreak of Cryptosporidiosis in Seoul, Korea

The first case of human cryptosporidiosis was reported in Korea in 1995; however, an outbreak of Cryptosporidium has not been reported in Korea until now. This paper describes the first outbreak of cryptosporidiosis in Korea. On May 24, 2012, a local public health center filed a report on 126 residents with gastrointestinal symptoms in an old apartment complex in Seoul. Epidemiological investigations were implemented on 125 of the 126 patients. The patients were reported continuously over a period of 22 days. Diarrhea was the most common clinical symptom, and lasted for 5 days on average. The tap water was the only common exposure of the patients. During the environmental investigation it was discovered that the water and septic tanks were situated closely and that the waste water pipes were corroded where they passed over the water pipes. Cryptosporidium parvum was detected in 3 of the 7 stool specimens by PCR-RFLP. A number of Cryptosporidium oocysts were also detected in the water specimens from the water tank. In conclusion, Cryptosporidium parvum was the key causal pathogen of this outbreak. It is presumed that the tap water was contaminated by a sewage leak from the aged pipelines.