Background/Aims: In 2019, the American Society for Gastrointestinal Endoscopy (ASGE) established clinical predictors for choledocholithiasis. Our study was designed to evaluate these predictors within the Korean clinical context, establish cutoff values, and develop a predictive model. Methods: This retrospective study analyzed patients who underwent laparoscopic cholecystectomy. The relationships between choledocholithiasis and predictors including age, blood tests, and imaging findings were assessed through univariate and multivariate logistic regression analyses. We established Korean cutoff values for these predictors and developed a scoring system for choledocholithiasis using a multivariate logistic regression. The performance of this scoring system was then compared with that of the 2019 ASGE guidelines through a receiver operating characteristic curve. Results: We established Korean cutoff values for age (>70 years), alanine aminotransferase (>26.5 U/L), aspartate aminotransferase (>28.5 U/L), gamma-glutamyl transferase (GGT; >82.5 U/L), alkaline phosphatase (ALP; >77.5 U/L), and total bilirubin (>0.95 mg/dL). In the multivariate analysis, only age >70 years, GGT >77.5 U/L, ALP >77.5 U/L, and common bile duct dilatation remained significant. We then developed a new Korean risk stratification model from the multivariate analysis, with an area under the curve of 0.777 (95% confidence interval, 0.75 to 0.81).Our model was stratified into the low-risk, intermediate-risk, and high-risk groups with the scores being <1.0, 1.0–5.5, and >5.5, respectively. Conclusions Predictors of choledocholithiasis in cholecystectomy patients and their cutoff values in Korean should be adjusted and further studies are needed to develop appropriate guidelines.

Background/Aims: In 2019, the American Society for Gastrointestinal Endoscopy (ASGE) established clinical predictors for choledocholithiasis. Our study was designed to evaluate these predictors within the Korean clinical context, establish cutoff values, and develop a predictive model. Methods: This retrospective study analyzed patients who underwent laparoscopic cholecystectomy. The relationships between choledocholithiasis and predictors including age, blood tests, and imaging findings were assessed through univariate and multivariate logistic regression analyses. We established Korean cutoff values for these predictors and developed a scoring system for choledocholithiasis using a multivariate logistic regression. The performance of this scoring system was then compared with that of the 2019 ASGE guidelines through a receiver operating characteristic curve. Results: We established Korean cutoff values for age (>70 years), alanine aminotransferase (>26.5 U/L), aspartate aminotransferase (>28.5 U/L), gamma-glutamyl transferase (GGT; >82.5 U/L), alkaline phosphatase (ALP; >77.5 U/L), and total bilirubin (>0.95 mg/dL). In the multivariate analysis, only age >70 years, GGT >77.5 U/L, ALP >77.5 U/L, and common bile duct dilatation remained significant. We then developed a new Korean risk stratification model from the multivariate analysis, with an area under the curve of 0.777 (95% confidence interval, 0.75 to 0.81).Our model was stratified into the low-risk, intermediate-risk, and high-risk groups with the scores being <1.0, 1.0–5.5, and >5.5, respectively. Conclusions Predictors of choledocholithiasis in cholecystectomy patients and their cutoff values in Korean should be adjusted and further studies are needed to develop appropriate guidelines.

Background/Aims: In 2019, the American Society for Gastrointestinal Endoscopy (ASGE) established clinical predictors for choledocholithiasis. Our study was designed to evaluate these predictors within the Korean clinical context, establish cutoff values, and develop a predictive model. Methods: This retrospective study analyzed patients who underwent laparoscopic cholecystectomy. The relationships between choledocholithiasis and predictors including age, blood tests, and imaging findings were assessed through univariate and multivariate logistic regression analyses. We established Korean cutoff values for these predictors and developed a scoring system for choledocholithiasis using a multivariate logistic regression. The performance of this scoring system was then compared with that of the 2019 ASGE guidelines through a receiver operating characteristic curve. Results: We established Korean cutoff values for age (>70 years), alanine aminotransferase (>26.5 U/L), aspartate aminotransferase (>28.5 U/L), gamma-glutamyl transferase (GGT; >82.5 U/L), alkaline phosphatase (ALP; >77.5 U/L), and total bilirubin (>0.95 mg/dL). In the multivariate analysis, only age >70 years, GGT >77.5 U/L, ALP >77.5 U/L, and common bile duct dilatation remained significant. We then developed a new Korean risk stratification model from the multivariate analysis, with an area under the curve of 0.777 (95% confidence interval, 0.75 to 0.81).Our model was stratified into the low-risk, intermediate-risk, and high-risk groups with the scores being <1.0, 1.0–5.5, and >5.5, respectively. Conclusions Predictors of choledocholithiasis in cholecystectomy patients and their cutoff values in Korean should be adjusted and further studies are needed to develop appropriate guidelines.

Background/Aims: In 2019, the American Society for Gastrointestinal Endoscopy (ASGE) established clinical predictors for choledocholithiasis. Our study was designed to evaluate these predictors within the Korean clinical context, establish cutoff values, and develop a predictive model. Methods: This retrospective study analyzed patients who underwent laparoscopic cholecystectomy. The relationships between choledocholithiasis and predictors including age, blood tests, and imaging findings were assessed through univariate and multivariate logistic regression analyses. We established Korean cutoff values for these predictors and developed a scoring system for choledocholithiasis using a multivariate logistic regression. The performance of this scoring system was then compared with that of the 2019 ASGE guidelines through a receiver operating characteristic curve. Results: We established Korean cutoff values for age (>70 years), alanine aminotransferase (>26.5 U/L), aspartate aminotransferase (>28.5 U/L), gamma-glutamyl transferase (GGT; >82.5 U/L), alkaline phosphatase (ALP; >77.5 U/L), and total bilirubin (>0.95 mg/dL). In the multivariate analysis, only age >70 years, GGT >77.5 U/L, ALP >77.5 U/L, and common bile duct dilatation remained significant. We then developed a new Korean risk stratification model from the multivariate analysis, with an area under the curve of 0.777 (95% confidence interval, 0.75 to 0.81).Our model was stratified into the low-risk, intermediate-risk, and high-risk groups with the scores being <1.0, 1.0–5.5, and >5.5, respectively. Conclusions Predictors of choledocholithiasis in cholecystectomy patients and their cutoff values in Korean should be adjusted and further studies are needed to develop appropriate guidelines.

Background: A decline in masticatory function may indicate brain dysfunction related to dementia, but the relationship between masticatory function and dementia risk remains unclear. This study aimed to investigate whether masticatory function is associated with the risk of cognitive decline and dementia. Methods: Data were obtained from the nationwide prospective cohort study of randomly sampled community-dwelling Koreans aged ≥ 60 years. The 5,064 non-demented participants, whose number of chewing cycles per bite was assessed by clinical interview, were followed for 8 years with biennial assessments of cognitive performance and clinical diagnoses of all-cause dementia and Alzheimer’s disease (AD). Structural brain magnetic resonance imaging was collected from a subset of cohort participants and their spouses for imaging analyses. Results: Males who chewed ≥ 30 cycles/bite had faster decline in global cognition and memory function and were at higher risk for incident all-cause dementia (hazard ratio [HR], 2.91; 95% confidence interval [CI], 1.18–7.18) and AD (HR, 3.22; 95% CI, 1.14–9.11) compared to males with less than 10 cycles/bite. Additionally, increased chewing cycles in males were associated with reduced brain volume, particularly in regions involved in compensatory cognitive control of mastication. There was no significant association between chewing cycles and the risk of dementia or brain volume in females. Conclusion Older men who frequently chew their meals could be considered a notable population at risk for dementia who should be carefully assessed for their cognitive trajectories.

Background/Aims: Non-celiac gluten sensitivity is characterized by intestinal and extra intestinal symptoms associated with the consumption of gluten-containing food. Since biomarkers for non-celiac gluten sensitivity are lacking, its prevalence is estimated based on self-reported symptoms. However, no data exist on self-reported non-celiac gluten sensitivity in the Korean population. Thus, we aim to investigate the prevalence of self-reported non-celiac gluten sensitivity in the Korean population and to determine its demographic and clinical characteristics. Methods: This study surveyed Korean participants aged 18-80 years who visited gastroenterology outpatient clinics at 9 tertiary hospitals in South Korea from January 2016 to February 2017. They were questioned regarding symptoms related to gluten ingestion: degree of discomfort (visual analog scale score), frequency, time of symptom onset, and duration. Abdominal discomfort caused by 11 differentkinds of gluten-containing Korean food items was investigated. Results: More non-celiac gluten sensitivity self-reporters were identified among those with irritable bowel syndrome (33.6%) than among controls (5.8%). Major gastrointestinal symptoms included bloating (75.0%), abdominal discomfort (71.3%), and belching (45.0%).Common extra-intestinal symptoms included fatigue (20.0%) and headache (13.7%). More than half of those who self-reported nonceliac gluten sensitivity (66.3%) developed symptoms within 1 hour of food ingestion, and symptoms were localized in the upper abdomen (37.5%) and entire abdomen (30.0%). Conclusion Our findings suggest that if there are gluten-related symptoms in irritable bowel syndrome, the possibility of accompanying non-celiacgluten sensitivity should be considered.

Purpose: The clinical implications of tumor-infiltrating T cell subsets and their spatial distribution in biliary tract cancer (BTC) patients treated with gemcitabine plus cisplatin were investigated. Materials and Methods: A total of 52 BTC patients treated with palliative gemcitabine plus cisplatin were included. Multiplexed immunohistochemistry was performed on tumor tissues, and immune infiltrates were separately analyzed for the stroma, tumor margin, and tumor core. Results: The density of CD8+ T cells, FoxP3- CD4+ helper T cells, and FoxP3+ CD4+ regulatory T cells was significantly higher in the tumor margin than in the stroma and tumor core. The density of LAG3- or TIM3-expressing CD8+ T cell and FoxP3- CD4+ helper T cell infiltrates was also higher in the tumor margin. In extrahepatic cholangiocarcinoma, there was a higher density of T cell subsets in the tumor core and regulatory T cells in all regions. A high density of FoxP3- CD4+ helper T cells in the tumor margin showed a trend toward better progression-free survival (PFS) (p=0.092) and significantly better overall survival (OS) (p=0.012). In multivariate analyses, a high density of FoxP3- CD4+ helper T cells in the tumor margin was independently associated with favorable PFS and OS. Conclusion The tumor margin is the major site for the active infiltration of T cell subsets with higher levels of LAG3 and TIM3 expression in BTC. The density of tumor margin-infiltrating FoxP3- CD4+ helper T cells may be associated with clinical outcomes in BTC patients treated with gemcitabine plus cisplatin.

The Korean Intermittent Exotropia Multicenter Study (KIEMS), which was initiated by the Korean Association of Pediatric Ophthalmology and Strabismus, is a collaborative multicenter study on intermittent exotropia in Korea. The KIEMS was designed to provide comprehensive information, including subjective and objective findings of intermittent exotropia in a large study population. A total of 65 strabismus specialists in 53 institutions contributed to this study, which, to date, is one of the largest clinical studies on intermittent exotropia. In this article, we provide a detailed methodology of the KIEMS to help future investigations that may use the KIEMS data.

Background: Firefighters inevitably encounter emotionally and physically stressful situations at work. Even firefighters without diagnosed post-traumatic stress disorder receive clinical attention because the nature of the profession exposes them to repetitive trauma and high occupational stress. This study investigated gray matter abnormalities related to high occupational stress in firefighters using voxel-based morphometry (VBM) and surface-based morphometry (SBM). Methods: We assessed 115 subjects (112 males and 3 females) using magnetic resonance imaging and evaluated occupational stress by the Korean Occupational Stress Scale-26 (KOSS-26). Subjects were classified into highly or lowly stressed groups based on the median value of the KOSS-26. Results: In VBM analysis, we found that firefighters with high occupational stress had lower gray matter volume (GMV) in both sides of the insula, the left amygdala, the right medial prefrontal cortex (mPFC), and the anterior cingulate cortex than firefighters with low occupational stress. In SBM analysis based on regions of interest, the GMV of the bilateral insula and right mPFC were also lower in the highly stressed group. Within the highly stressed group, low GMV of the insula was significantly correlated with the length of service (left: r = −0.347, P = 0.009; right: r = −0.333, P = 0.012). Conclusion Our findings suggest that regional GMV abnormalities are related to occupational stress. Regional gray matter abnormalities and related emotional dysregulation may contribute to firefighter susceptibility to burnout.

The Korean Intermittent Exotropia Multicenter Study (KIEMS), which was initiated by the Korean Association of Pediatric Ophthalmology and Strabismus, is a collaborative multicenter study on intermittent exotropia in Korea. The KIEMS was designed to provide comprehensive information, including subjective and objective findings of intermittent exotropia in a large study population. A total of 65 strabismus specialists in 53 institutions contributed to this study, which, to date, is one of the largest clinical studies on intermittent exotropia. In this article, we provide a detailed methodology of the KIEMS to help future investigations that may use the KIEMS data.