The Effect of Intervention for Improving Colonoscopy Quality Is Associated with the Personality Traits of Endoscopists.

Background/Aims: This study investigated whether the personality traits of endoscopists are associated with the effect of interventions for the improvement of colonoscopy quality. Methods: This prospective, multicenter, single-blind study was performed with 13 endoscopists in three health screening centers over a 12-month period. Quality indicators (QIs), including adenoma detection rate (ADR), polyp detection rate (PDR), and withdrawal time, were measured every 3 months. Consecutive interventions for the improvement of colonoscopy quality were conducted every 3 months, which included the personal notification of QIs, the in-group notification of QIs, and finally a targeted "quality education" session. The personality traits of each endoscopist were evaluated for perfectionism, fear of negative evaluation, and cognitive flexibility after the last QI assessment. Results: A total of 4,095 colonoscopies were evaluated to measure the QIs of the individual endoscopists for 12 months. The mean ADR, PDR, and withdrawal time of the 13 endoscopists were 32.3%, 47.7%, and 394 seconds at baseline and increased to 39.0%, 55.1%, and 430 seconds by the end of the study (p=0.003, p=0.006, and p=0.004, respectively). Among the three interventions, only quality education significantly improved QIs: ADR, 36.0% to 39.0% (odds ratio, 1.28; 95% confidence interval, 1.01 to 1.63). The improvement of ADR and PDR by education was significantly associated with perfectionism (r=0.617, p=0.033 and r=0.635, p=0.027, respectively) and fear of negative evaluation (r=0.704, p=0.011 and r=0.761, p=0.004, respectively). Conclusions: Education can improve colonoscopy quality, and its effect size is associated with an endoscopist's personal traits such as perfectionism and fear of negative evaluation (Clinical-Trials.gov Registry NCT03796169).

Clinical Outcomes of Upfront Primary Tumor Resection in Synchronous Unresectable Metastatic Colorectal Cancer.

The role of upfront primary tumor resection (PTR) in patients with unresectable metastatic colorectal cancer without severe symptoms remains controversial. We retrospectively analyzed the role of PTR in overall survival (OS) in this population. Among the 205 patients who enrolled, the PTR group (n = 42) showed better performance (p = 0.061), had higher frequencies of right-sided origin (p = 0.058), the T4 stage (p = 0.003), the M1a stage (p = 0.012), and <2 organ metastases (p = 0.002), and received fewer targeted agents (p = 0.011) than the chemotherapy group (n = 163). The PTR group showed a trend for longer OS (20.5 versus 16.0 months, p = 0.064) but was not related to OS in Cox regression multivariate analysis (p = 0.220). The male sex (p = 0.061), a good performance status (p = 0.078), the T3 stage (p = 0.060), the M1a stage (p = 0.042), <2 organ metastases (p = 0.035), an RAS wild tumor (p = 0.054), and the administration of targeted agents (p = 0.037), especially bevacizumab (p = 0.067), seemed to be related to PTR benefits. Upfront PTR could be considered beneficial in some subgroups, but these findings require larger studies to verify.

Fracture Risk in Middle-Aged and Older Patients With Inflammatory Bowel Disease: A Korean Nationwide Population-Based Cohort Study.

BACKGROUND: Fracture risks and associated factors are poorly understood in middle-aged and older Asian populations with inflammatory bowel disease (IBD). Therefore, we investigated fracture risk and the effects of comorbidities and lifestyle habits on the risk of developing fractures in middle-aged and older Korean patients with IBD. METHODS: We conducted a nationwide population-based cohort study using data from the National Health Insurance Corporation Database. Patients with IBD who underwent the National Screening Program and were over 40 years of age were included in the study. We compared patients with age- and sex-matched controls. The incidence of fractures, including vertebral, hip, and other sites, was determined using claims data. RESULTS: The risk of total fractures and vertebral fractures was significantly higher in the IBD group (adjusted hazard ratio [HR], 1.31, 95% confidence interval [CI], 1.16-1.48; adjusted HR, 1.59, 95% CI, 1.33-1.92, respectively). Obesity, diabetes, hypertension, and lack of exercise were associated with increased fracture risk in patients with ulcerative colitis (UC). In contrast, the risk increases in patients with Crohn's disease regardless of comorbidities and lifestyle preferences. CONCLUSION: The risk of bone fracture, especially vertebral fracture, is high in middle-aged and older Korean patients with IBD. Obesity, diabetes, hypertension, and lack of exercise are all risk factors associated with bone fractures in patients with UC. These findings are helpful for clinicians to educate patients with IBD on bone health and raise awareness of bone fractures in patients with UC who have specific risk factors.

Changes in fecal metabolic and lipidomic features by anti-TNF treatment and prediction of clinical remission in patients with ulcerative colitis.

Background: Therapeutic targets for ulcerative colitis (UC) and prediction models of antitumor necrosis factor (TNF) therapy outcomes have not been fully reported. Objective: Investigate the characteristic metabolite and lipid profiles of fecal samples of UC patients before and after adalimumab treatment and develop a prediction model of clinical remission following adalimumab treatment. Design: Prospective, observational, multicenter study was conducted on moderate-to-severe UC patients (n = 116). Methods: Fecal samples were collected from UC patients at 8 and 56 weeks of adalimumab treatment and from healthy controls (HC, n = 37). Clinical remission was assessed using the Mayo score. Metabolomic and lipidomic analyses were performed using gas chromatography mass spectrometry and nano electrospray ionization mass spectrometry, respectively. Orthogonal partial least squares discriminant analysis was performed to establish a remission prediction model. Results: Fecal metabolites in UC patients markedly differed from those in HC at baseline and were changed similarly to those in HC during treatment; however, lipid profiles did not show these patterns. After treatment, the fecal characteristics of remitters (RM) were closer to those of HC than to those of non-remitters (NRM). At 8 and 56 weeks, amino acid levels in RM were lower than those in NRM and similar to those in HC. After 56 weeks, levels of 3-hydroxybutyrate, lysine, and phenethylamine decreased, and dodecanoate level increased in RM similarly to those in HC. The prediction model of long-term remission in male patients based on lipid biomarkers showed a higher performance than clinical markers. Conclusion: Fecal metabolites in UC patients markedly differ from those in HC, and the levels in RM are changed similarly to those in HC after anti-TNF therapy. Moreover, 3-hydroxybutyrate, lysine, phenethylamine, and dodecanoate are suggested as potential therapeutic targets for UC. A prediction model of long-term remission based on lipid biomarkers may help implement personalized treatment.

Assessment of Fatigue and Associated Factors in Patients with Inflammatory Bowel Disease: A Questionnaire-Based Study.

Although fatigue is common in patients with inflammatory bowel disease (IBD), it often goes unrecognized and untreated. We investigated the degree of fatigue and associated factors in patients with IBD. A multicenter study involving 147 IBD patients was conducted at five academic hospitals from August 2019 to December 2021. Fatigue was evaluated using the validated Korean version of the Multidimensional Fatigue Inventory (MFI-K). Among 97 ulcerative colitis patients and 50 Crohn's disease patients, the mean total MFI-K score was 59.0 ± 5.5, which corresponded to a moderate-to-severe level of fatigue. Moderate-to-severe disease activity was found to be significantly associated with a higher general and physical fatigue subscale MFI-K score compared to remission-to-mild disease activity (17.6 ± 1.7 vs. 16.7 ± 2.0, p = 0.009), while the use of biologics was associated with a lower total MFI-K score (57.3 ± 5.0 vs. 59.5 ± 5.5, p = 0.031). In multiple linear regression, the total MFI-K score was positively correlated with a history of surgery for IBD, while it was negatively correlated with the use of biologics. Depression was positively correlated with the reduced motivation subscale score. The degree of fatigue in patients with IBD was high. Disease activity, the use of biologics, a history of surgery for IBD, and depression were associated with fatigue.

Oral Sulfate Solution Is as Effective as Polyethylene Glycol with Ascorbic Acid in a Split Method for Bowel Preparation in Patients with Inactive Ulcerative Colitis: A Randomized, Multicenter, and Single-Blind Clinical Trial.

Background/Aims: Low-volume preparations for colonoscopy are gaining attention for their higher acceptability. However, the efficacy and safety of oral sulfate solution (OSS) preparations in patients with ulcerative colitis (UC) has not been well known. Therefore, we aimed to compare OSS and 2-L polyethylene glycol with ascorbic acid (PEG+Asc) for bowel preparation in inactive UC. Methods: A multicenter, randomized, single-blind study was conducted at six tertiary referral hospitals in Korea. Outpatients with UC who had stable disease activity were randomly allocated to the OSS group or the 2-L PEG+Asc group for bowel preparation before colonoscopy. The study outcomes included treatment efficacy, safety, tolerability, and acceptability. Bowel cleansing was assessed using the Boston Bowel Preparation Scale and rated as successful cleansing if the score was ≥6. Patient acceptance and tolerability were assessed using a 4-point ordinal scale. Additionally, disease activity and laboratory data before and after colonoscopy were evaluated to check for safety. Results: The OSS and 2-L PEG+Asc groups included 92 and 93 participants, respectively. No significant between-group difference was noted in successful cleansing (OSS [96.7%] vs 2-L PEG+Asc [97.8%], p=0.64). Moreover, the safety, acceptance, and tolerability were not significantly different (all p>0.05). Furthermore, no significant changes were found in serum electrolytes or disease activity in either group. Conclusions: OSS is effective for colonoscopy cleansing, has acceptable tolerability, and does not affect disease activity; thus, it can be used safely for bowel preparation in patients with inactive UC.

Compositional changes in fecal microbiota associated with clinical phenotypes and prognosis in Korean patients with inflammatory bowel disease.

BACKGROUND/AIMS: The fecal microbiota of Korean patients with inflammatory bowel disease (IBD) was investigated with respect to disease phenotypes and taxonomic biomarkers for diagnosis and prognosis of IBD. METHODS: Fecal samples from 70 ulcerative colitis (UC) patients, 39 Crohn's disease (CD) patients, and 100 healthy control individuals (HC) were collected. The fecal samples were amplified via polymerase chain reaction and sequenced using Illumina MiSeq. The relationships between fecal bacteria and clinical phenotypes were analyzed using the EzBioCloud database and 16S microbiome pipeline. RESULTS: The alpha-diversity of fecal bacteria was significantly lower in UC and CD (P<0.05) compared to that in HC. Bacterial community compositions in UC and CD were significantly different from that of HC according to Bray-Curtis dissimilarities, and there was also a difference between community composition in UC and CD (P=0.01). In UC, alpha-diversity was further decreased when the disease was more severe and the extent of disease was greater, and community composition significantly differed depending on the extent of the disease. We identified 9 biomarkers of severity and 6 biomarkers of the extent of UC. We also identified 5 biomarkers of active disease and 3 biomarkers of ileocolonic involvement in CD. Lachnospiraceae and Ruminococcus gnavus were biomarkers for better prognosis in CD. CONCLUSIONS: The fecal microbiota profiles of IBD patients were different from those of HC, and several bacterial taxa may be used as biomarkers to determine disease phenotypes and prognosis. These data may also help discover new therapeutic targets for IBD.

Early Infliximab Trough Levels Predict the Long-term Efficacy of Infliximab in a Randomized Controlled Trial in Patients with Active Crohn's Disease Comparing, between CT-P13 and Originator Infliximab.

Background/Aims: The clinical efficacy and safety of CT-P13 are comparable to originator infliximab for Crohn's disease in CT-P13 3.4 study (NCT02096861). We performed a multivariate logistic analysis to demonstrate the association between early infliximab trough levels and treatment outcomes of CT-P13 and originator infliximab. Methods: Early serum infliximab trough levels and anti-drug antibody (ADA) levels were compared between CT-P13 (n=100) and originator infliximab (n=98) groups. Receiver operating characteristic (ROC) analysis and multivariate logistic analysis were conducted to identify optimal cutoffs of serum infliximab trough levels and predictive factors for clinical outcomes. Results: The median infliximab trough levels were not different between CT-P13 and originator infliximab groups at week 6, week 14, and in median ADA levels at week 14, respectively. ROC analysis found an infliximab concentration threshold of 4.5 µg/mL at week 6 and 4.0 µg/mL at week 14 as the cutoff value with the highest accuracy for the prediction of clinical outcomes. Serum infliximab trough levels at weeks 6 and 14 predicted clinical remission at weeks 30 and 54, and endoscopic remission at week 54. The combinations of clinical remission or C-reactive protein normalization with an early infliximab trough level improved the prediction of long-term clinical or endoscopic remission. Conclusions: A threshold in serum infliximab trough level at week 6 and week 14 was highly predictive for long-term clinical outcomes. There were no statistical differences in serum infliximab trough levels and ADA levels between CT-P13 and originator infliximab.

Reliability and Validity of Korean Version of Crohn's and Ulcerative Colitis Questionnaire-8.

Background: Patients with inflammatory bowel disease (IBD) have a decreased quality of life (QoL), the improvement of which is a treatment goal. The CUCQ-8 is a verified simple and effective QoL measurement tool. We validated the Korean version of CUCQ-8 with the approval of its developer. Methods: We investigated the correlation between the Korean version of CUCQ-8 and the IBDQ-32 in patients with IBD. Results: In all, 147 subjects (male, 97 (66.0%); female, 50 (34.0%); mean age 36.2 ± 13.5 years) were analyzed. Cronbach's alpha coefficient of the CUCQ-8 was 0.833, indicating very high internal consistency. The Korean version of the CUCQ-8 showed a significant correlation with the IBDQ-32 and its subscales (correlation coefficient, >0.75). Conclusions: The Korean version of the CUCQ-8 has high reliability and construct validity and can be used to evaluate the QoL of patients with IBD.

Clinical Features and Long-term Prognosis of Crohn's Disease in Korea: Results from the Prospective CONNECT Study.

Background/Aims: The prospective Crohn's Disease Clinical Network and Cohort Study is a nationwide multicenter cohort study of patients with Crohn's disease (CD) in Korea, aiming to prospectively investigate the clinical features and long-term prognosis associated with CD. Methods: Patients diagnosed with CD between January 2009 and September 2019 were prospectively enrolled. They were divided into two cohorts according to the year of diagnosis: cohort 1 (diagnosed between 2009 and 2011) versus cohort 2 (between 2012 and 2019). Results: A total of 1,175 patients were included, and the median follow-up duration was 68 months (interquartile range, 39.0 to 91.0 months). The treatment-free durations for thiopurines (p<0.001) and anti-tumor necrosis factor agents (p=0.018) of cohort 2 were shorter than those of cohort 1. Among 887 patients with B1 behavior at diagnosis, 149 patients (16.8%) progressed to either B2 or B3 behavior during follow-up. Early use of thiopurine was associated with a reduced risk of behavioral progression (adjusted hazard ratio [aHR], 0.69; 95% confidence interval [CI], 0.50 to 0.90), and family history of inflammatory bowel disease was associated with an increased risk of behavioral progression (aHR, 2.29; 95% CI, 1.16 to 4.50). One hundred forty-one patients (12.0%) underwent intestinal resection, and the intestinal resection-free survival time was significantly longer in cohort 2 than in cohort 1 (p=0.003). The early use of thiopurines (aHR, 0.35; 95% CI, 0.23 to 0.51) was independently associated with a reduced risk of intestinal resection. Conclusions: The prognosis of CD in Korea appears to have improved over time, as evidenced by the decreasing intestinal resection rate. Early use of thiopurines was associated with an improved prognosis represented by a reduced risk of intestinal resection.

Quality of Life in Newly Diagnosed Moderate-to-Severe Ulcerative Colitis: Changes in the MOSAIK Cohort Over 1 Year.

Background/Aims: Improving quality of life has been gaining importance in ulcerative colitis (UC) management. The aim of this study was to investigate changes in health-related quality of life (HRQL) and related factors in patients with moderate-to-severe UC. Methods: A multicenter, hospital-based, prospective study was performed using a Moderate-to-Severe Ulcerative Colitis Cohort in Korea (the MOSAIK). Changes in HRQL, evaluated using the 12-Item Short Form Health Survey (SF-12) and Inflammatory Bowel Disease Questionnaire (IBDQ), were analyzed at the time of diagnosis and 1 year later. Results: In a sample of 276 patients, the mean age was 38.4 years, and the majority of patients were male (59.8%). HRQL tended to increase in both the IBDQ and SF-12 1 year after diagnosis. A higher partial Mayo score was significantly related to poorer HRQL on the IBDQ and SF-12 in a linear mixed model (p<0.01). Inflammatory markers such as C-reactive protein (CRP) or erythrocyte sedimentation rate also showed a negative correlation on HRQL (p<0.05). Patients whose IBDQ score improved by 16 or more (71.2%) in 1 year were younger, tended to be nonsmokers, and had a lower partial Mayo score and CRP than those whose IBDQ score did not. There was no significant association between HRQL and disease extent, treatments at diagnosis, or the highest treatment step during the 1-year period. Conclusions: Optimally controlled disease status improves HRQL in patients with moderate-to-severe UC. The partial Mayo score and inflammatory markers may be potential indicators reflecting the influence of UC on patient`s daily lives.

Clinical Course of Hepatitis B Viral Infection in Patients Undergoing Anti-Tumor Necrosis Factor α Therapy for Inflammatory Bowel Disease.

Background/Aims: Little is known about the clinical course of hepatitis B virus (HBV)-infected patients undergoing anti-tumor necrosis factor α (TNF-α) therapy for inflammatory bowel disease (IBD). We aimed to investigate the clinical course of HBV infection and IBD and to analyze liver dysfunction risks in patients undergoing anti-TNF-α therapy. Methods: This retrospective multinational study involved multiple centers in Korea, China, Taiwan, and Japan. We enrolled IBD patients with chronic or resolved HBV infection, who received anti-TNF-α therapy. The patients' medical records were reviewed, and data were collected using a web-based case report form. Results: Overall, 191 patients (77 ulcerative colitis and 114 Crohn's disease) were included, 28.3% of whom received prophylactic antivirals. During a median follow-up duration of 32.4 months, 7.3% of patients experienced liver dysfunction due to HBV reactivation. Among patients with chronic HBV infection, the proportion experiencing liver dysfunction was significantly higher in the non-prophylaxis group (26% vs 8%, p=0.02). Liver dysfunction occurred in one patient with resolved HBV infection. Antiviral prophylaxis was independently associated with an 84% reduction in liver dysfunction risk in patients with chronic HBV infection (odds ratio, 0.16; 95% confidence interval, 0.04 to 0.66; p=0.01). The clinical course of IBD was not associated with liver dysfunction or the administration of antiviral prophylaxis. Conclusions: Liver dysfunction due to HBV reactivation can occur in HBV-infected IBD patients treated with anti-TNF-α agents. Careful monitoring is needed in these patients, and antivirals should be administered, especially to those with chronic HBV infection.

Clinical outcomes and predictors of response for adalimumab in patients with moderately to severely active ulcerative colitis: a KASID prospective multicenter cohort study.

BACKGROUND/AIMS: This study assessed the efficacy and safety of adalimumab (ADA) and explored predictors of response in Korean patients with ulcerative colitis (UC). METHODS: A prospective, observational, multicenter study was conducted over 56 weeks in adult patients with moderately to severely active UC who received ADA. Clinical response, remission, and mucosal healing were assessed using the Mayo score. RESULTS: A total of 146 patients were enrolled from 17 academic hospitals. Clinical response rates were 52.1% and 37.7% and clinical remission rates were 24.0% and 22.0% at weeks 8 and 56, respectively. Mucosal healing rates were 39.0% and 30.1% at weeks 8 and 56, respectively. Prior use of anti-tumor necrosis factor-α (anti-TNF-α) did not affect clinical and endoscopic responses. The ADA drug level was significantly higher in patients with better outcomes at week 8 (P<0.05). In patients with lower endoscopic activity, higher body mass index, and higher serum albumin levels at baseline, the clinical response rate was higher at week 8. In patients with lower Mayo scores and C-reactive protein levels, clinical responses, and mucosal healing at week 8, the clinical response rate was higher at week 56. Serious adverse drug reactions were identified in 2.8% of patients. CONCLUSIONS: ADA is effective and safe for induction and maintenance in Korean patients with UC, regardless of prior anti-TNF-α therapy. The ADA drug level is associated with the efficacy of induction therapy. Patients with better short-term outcomes were predictive of those with an improved long-term response.

The real-world outcomes of vedolizumab in patients with ulcerative colitis in Korea: a multicenter retrospective study.

AIM: This study examined the real-world effectiveness and safety outcomes of vedolizumab in ulcerative colitis (UC) patients who had failed anti-tumor necrosis factor (anti-TNF) therapy in Korea. METHODS: A retrospective chart review study was conducted in adults with moderate to severely active UC who had failed anti-TNF agents and subsequently received vedolizumab. Clinical response and clinical remission at week 6 and 14 after vedolizumab initiation was evaluated. Safety outcomes were also reported. Outcome rates were compared with a matched sub-cohort derived from the open-label sub-cohort of the GEMINI 1 trial using the optimal matching method. RESULTS: A total of 105 patients (mean age, 45.3 years; 63.8% male) were included. At week 6, 55.8% (n = 43/77) achieved a clinical response and 18.2% (n = 14/77) achieved clinical remission. At week 14, 73.2% (n = 52/71) achieved a clinical response and 39.4% (n = 28/71) achieved clinical remission. When non-response imputation was used, the clinical response rate at week 6 and week 14 were 40.1% (n = 43/105) and 49.5% (n = 52/105) respectively. Of the 105 patients, 16 (15.2%) experienced at least one adverse event. The matched analysis showed that the clinical response rate at week 6 was higher in the matched sub-cohort of this study (24/47, 51.1%) versus the matched sub-cohort from the GEMINI 1 open-label cohort (12/47, 34.3%, p = 0.019). The clinical remission rates at week 6 were similar (7/47, 14.9% versus 9/47, 19.1%, p = 0.785). CONCLUSIONS: In the real-world setting, vedolizumab is effective and well tolerated within the first 14 weeks of use in Korea. The proportion of patients experiencing clinical response and clinical remission at 6 and 14 weeks appeared to be largely consistent with that observed in real-world studies from other regions and populations.

Effect of prophylactic clip application for the prevention of postpolypectomy bleeding of large pedunculated colonic polyps: a randomized controlled trial.

BACKGROUND AND AIMS: Prophylactic application of a hemoclip has been suggested as an alternative to the use of an endoloop for the prevention of postpolypectomy bleeding (PPB) when resecting large, pedunculated colorectal polyps. Therefore, this multicenter, randomized controlled trial investigated the efficacy of prophylactic hemoclip application to reduce PPB during the resection of large pedunculated polyps. METHODS: Large pedunculated polyps (≥10 mm in head diameter) were eligible for inclusion. Polyps were randomized into a study arm (where clips were applied before resection) and a control arm (without pretreatment). The primary outcome was the rate of PPB in each group. PPB included immediate PPB (IPPB) and delayed PPB (DPPB). IPPB was defined as blood oozing (≥1 minute) or active spurting occurring immediately after polyp resection. DPPB was defined as rectal bleeding, occurring after completion of the colonoscopy. RESULTS: In total, 238 polyps from 204 patients were randomized into the clip arm (119 polyps) or the control arm (119 polyps). Overall bleeding adverse events were observed in 20 cases (IPPB, 16; DPPB, 4). The rate of overall PPB, IPPB, and DPPB was 8.4%, 6.7%, and 1.7%, respectively, for all polyps. The rate of overall PPB (clip 4.2% vs control 12.6%, P = .033) and IPPB (clip 2.5% vs control 10.9%, P = .017) was significantly lower in the clip arm than the control arm. CONCLUSIONS: Prophylactic clipping before resecting large pedunculated polyps can reduce overall PPB and IPPB compared with no prior treatment. Therefore, prophylactic clipping may be considered before resection of large pedunculated polyps. (Clinical trial registration number: NCT02156193.).

Clinical Outcomes and Response Predictors of Vedolizumab Induction Treatment for Korean Patients With Inflammatory Bowel Diseases Who Failed Anti-TNF Therapy: A KASID Prospective Multicenter Cohort Study.

BACKGROUND: We investigated the real-life effectiveness and safety of vedolizumab (VDZ) induction therapy among Korean patients with Crohn disease (CD) or ulcerative colitis (UC) for whom anti-tumor necrosis factor therapy previously failed. METHODS: Adult patients who started VDZ induction therapy at 16 centers were prospectively enrolled in the Korean VDZ nationwide registry. The coprimary outcomes were clinical remission, defined as a Crohn's Disease Activity Index score <150 points and a partial Mayo score ≤2 points with a combined rectal bleeding and stool frequency subscore ≤1 point at week 14 and endoscopic remission defined as a Mayo endoscopic subscore ≤1 point. We also analyzed predictors of clinical remission. RESULTS: Between August 2017 and November 2019, a total of 158 patients (80 with CD and 78 with UC) received VDZ induction therapy. Clinical remission rates among patients with CD and patients with UC were 44.1% and 44.0%, respectively. Among patients with UC, the endoscopic remission rate was 32.4%. Clinical response and remission rates showed increasing trends during induction therapy. Multivariable analysis revealed that clinical response at week 6 was the only predictor of clinical remission at week 14 for both patients with CD and patients with UC. Among patients who experienced 1 or more adverse events (n = 71; 44.9%), disease exacerbation (n = 28; 17.7%) was the most common adverse event. CONCLUSIONS: Among Korean patients with CD or UC for whom anti-tumor necrosis factor therapy failed, VDZ induction therapy was effective and safe. The early clinical response was associated with clinical remission after VDZ induction therapy.

Improved classification and localization approach to small bowel capsule endoscopy using convolutional neural network.

BACKGROUND: Although great advances in artificial intelligence for interpreting small bowel capsule endoscopy (SBCE) images have been made in recent years, its practical use is still limited. The aim of this study was to develop a more practical convolutional neural network (CNN) algorithm for the automatic detection of various small bowel lesions. METHODS: A total of 7556 images were collected for the training dataset from 526 SBCE videos. Abnormal images were classified into two categories: hemorrhagic lesions (red spot/angioectasia/active bleeding) and ulcerative lesions (erosion/ulcer/stricture). A CNN algorithm based on VGGNet was trained in two different ways: the combined model (hemorrhagic and ulcerative lesions trained separately) and the binary model (all abnormal images trained without discrimination). The detected lesions were visualized using a gradient class activation map (Grad-CAM). The two models were validated using 5,760 independent images taken at two other academic hospitals. RESULTS: Both the combined and binary models acquired high accuracy for lesion detection, and the difference between the two models was not significant (96.83% vs 96.62%, P = 0.122). However, the combined model showed higher sensitivity (97.61% vs 95.07%, P < 0.001) and higher accuracy for individual lesions from the hemorrhagic and ulcerative categories than the binary model. The combined model also revealed more accurate localization of the culprit area on images evaluated by the Grad-CAM. CONCLUSIONS: Diagnostic sensitivity and classification of small bowel lesions using a convolutional neural network are improved by the independent training for hemorrhagic and ulcerative lesions. Grad-CAM is highly effective in localizing the lesions.

Waist circumference, body mass index, and colorectal cancer risk according to diabetes status: A Korean nationwide population-based cohort study.

BACKGROUND AND AIM: We investigated the relationship of BMI and waist circumference with the risk of colorectal cancer (CRC) using a population-based cohort database and to explore the relationship of CRC with diabetes status. METHODS: Retrospective data (age >20 years) on anthropometric variables, blood parameters of fasting sugar, lipid levels, and blood pressure were collected from the National Health Insurance Corporation database between 2009 and 2012. Cox regression models were used to estimate hazard ratio (HR) and corresponding 95% confidence intervals (95% CI). RESULTS: Of the 23 121 360 people studied, 120 579 were diagnosed with CRC after a median follow-up period of 5.4 years. Both waist circumference and body mass index were positively associated with increased risk of CRC, regardless of age or sex. After mutual adjustment, only waist circumference was significantly associated with increased risk of CRC (HR = 1.275, 95% CI: 1.205-1.349). When the risk of CRC was compared according to diabetes status among people with the same waist circumference range, risk of CRC was higher for those with worse diabetes status. CONCLUSION: When waist circumference and body mass index were mutually adjusted, only waist circumference was associated with CRC risk. In addition, the risk of CRC is gradually higher in those with worsening diabetes, even if their waist circumferences are within the same range.

Long-term outcomes of infliximab in a real-world multicenter cohort of patients with acute severe ulcerative colitis.

BACKGROUND/AIMS: Infliximab (IFX) has proven effective as rescue therapy in steroid-refractory acute severe ulcerative colitis (ASUC), however, the long-term real-world data are scarce. Our study aimed to assess the long-term treatment outcomes of IFX in a real-life cohort. METHODS: We established a multicenter retrospective cohort of hospitalized patients with ASUC, who met Truelove and Witt's criteria and received intravenous corticosteroid (IVCS) or IFX during index hospitalization between 2006 and 2016 in 5 university hospitals in Korea. The cohort was systematically followed up until colectomy, death or last follow-up visit. RESULTS: A total of 296 patients were followed up for a mean of 68.9 ± 44.0 months. During index hospitalization, 49 patients were treated with IFX; as rescue therapy for IVCS failure in 37 and as first-line medical therapy for ASUC in 12. All patients treated with IFX avoided colectomy during index hospitalization. The cumulative rates of rehospitalization and colectomy were 20.4% and 6.1% at 3 months and 39.6% and 18.8% at the end of follow-up, respectively. Patients treated with IFX presented with significantly shorter colectomy-free survival than IVCS responders (P= 0.04, log-rank test). Both cytomegalovirus colitis and Clostridioides difficile infection (CDI) were the significant predictors of colectomy in the overall study cohort (hazard ratios of 6.57 and 4.61, respectively). There were no fatalities. CONCLUSIONS: Our real-world cohort study demonstrated that IFX is an effective therapeutic option in Korean patients with ASUC, irrespective of IFX indication. Aggressive vigilance for cytomegalovirus colitis and CDI is warranted for hospitalized patients with ASUC.