Summary and comparison of recently updated post-polypectomy surveillance guidelines

Recently, updated guidelines for post-polypectomy surveillance have been published by the U.S. Multi‐Society Task Force (USMSTF), the British Society of Gastroenterology/Association of Coloproctology of Great Britain and Ireland/Public Health England (BSG/ACPGBI/PHE), the European Society of Gastrointestinal Endoscopy (ESGE), the Japan Gastroenterological Endoscopy Society (JGES), and the Korean Multi-Society Taskforce Committee. This review summarizes and compares the updated recommendations of these 5 guidelines. There are some differences between the guidelines for the recommended post-polypectomy surveillance intervals. In particular, there are prominent differences between the guidelines for 1–4 tubular adenomas < 10 mm with low-grade dysplasia (nonadvanced adenomas [NAAs]) and tubulovillous or villous adenomas. The USMSTF, JGES, and Korean guidelines recommend colonoscopic surveillance for patients with 1–4 NAAs and those with tubulovillous or villous adenomas, whereas the BSG/ACPGBI/PHE and ESGE guidelines do not recommend endoscopic surveillance for such patients. Surveillance recommendations for patients with serrated polyps (SPs) are limited. Although the USMSTF guidelines provide specific recommendations for patients who have undergone SPs removal, these are weak and based on very lowquality evidence. Future studies should examine this topic to better guide the surveillance recommendations for patients with SPs. For countries that do not have separate guidelines, we hope that this review article will help select the most appropriate guidelines as per each country’s healthcare environment.

Efficacy and Tolerability of 14-Day Tegoprazan- versus Rabeprazole-Based Triple Therapy for Eradication of Helicobacter pylori: A Real-World Evidence Study

Background/Aims@#Tegoprazan, a new, fast, and strong potassium-competitive acid blocker, has been approved for the treatment of gastric acid-related diseases in Korea. However, realworld clinical data regarding this drug are scarce. We aimed to compare the Helicobacter pylori eradication rates of tegoprazan- and rabeprazole-based triple therapy. @*Methods@#We retrospectively reviewed data from patients who received first-line treatment for H. pylori infection using tegoprazan- or rabeprazole-based triple therapy for 2 weeks (50 mg tegoprazan or 20 mg rabeprazole+1,000 mg amoxicillin+500 mg clarithromycin twice daily). The primary endpoint was the eradication rate as determined by intention-to-treat analysis. @*Results@#Of the 677 patients included in our study, 344 and 333 received tegoprazan-based and rabeprazole-based triple therapy, respectively. The eradication rate from intention-to-treat analysis was 76.7% (95% confidence interval [CI], 72.1% to 81.0%) for tegoprazan-based triple therapy and 75.4% (95% CI, 70.5% to 79.8%) for rabeprazole-based triple therapy. There was no significant difference in the eradication rates between the two groups (p>0.999). Per-protocol analysis also revealed no significant difference between the eradication rates of the two groups (tegoprazan 83.4% [95% CI, 79.0% to 87.2%] vs rabeprazole 83.5% [79.0% to 87.4%], p>0.999).Furthermore, there was no significant difference in adverse event rates between the two groups (tegoprazan, 27.6%; rabeprazole, 25.8%; p=0.604). @*Conclusions@#The eradication rate of tegoprazan-based triple therapy was similar to that of rabeprazole-based triple therapy. Further studies on the dose-escalation effect of tegoprazan for H. pylori eradication and the efficacy of tegoprazan in regimens other than conventional triple therapy are needed.

Positive fecal immunochemical test results are associated with non-colorectal cancer mortality

Background/Aims@#Studies have reported an association between fecal occult blood and increased all-cause, non-colorectal cancer (CRC) as well as CRC mortality. This study aimed to determine whether positive fecal immunochemistry test (FIT) results are associated with death from various causes in the South Korean population. @*Methods@#Using the Korean National Cancer Screening Program database, we collected data on patients who underwent FIT between 2009 and 2011. @*Results@#Of the 5,932,544 participants, 380,789 (6.4%) had positive FIT results. FIT-positive participants had a higher mortality rate than FIT-negative participants from CRC (1.33 and 0.21 per 1,000 person-years, p < 0.001, respectively) and non-CRC causes (10.40 and 7.50 per 1,000 person-years, p < 0.001, respectively). Despite adjusting for age, sex, smoking status, alcohol consumption habits, body mass index, comorbidity, and aspirin use, FIT positivity was associated with an increased risk of dying from all non-CRC causes (adjusted hazard ratio [aHR], 1.17; 95% confidence interval [CI], 1.15 to 1.18) and CRC (aHR, 5.61; 95% CI, 5.40 to 5.84). Additionally, FIT positivity was significantly associated with increased mortality from circulatory disease (aHR, 1.14; 95% CI, 1.11 to 1.17), respiratory disease (aHR, 1.14; 95% CI, 1.09 to 1.19), digestive disease (aHR, 1.57; 95% CI, 1.48 to 1.66), neuropsychological disease (aHR, 1.08; 95% CI, 1.01 to 1.16), blood and endocrine diseases (aHR, 1.10; 95% CI, 1.04 to 1.17), and external factors (aHR, 1.16; 95% CI, 1.11 to 1.20). @*Conclusions@#Positive FIT results are associated with an increased risk of mortality from CRC and various other chronic diseases, suggesting that it could be a predictor of mortality independent of its association with CRC.

A Pilot Study of Peritumor Administration of 5-FU for Preventing Bleeding in Advanced Gastric Cancer / 대한소화기학회지

Five-FU is a potent chemotherapeutic agent for suppressing endothelial cell growth. The purpose of this study was to investigate the usefulness of local peritumor injection of 5-FU for patients with advanced gastric cancer (AGC) for the prevention of anemia. Between January 2020 and January 2022, patients aged 18 years or older with AGC and moderate anemia were included. A total of 200 mg of 5-FU was injected per session at ten points of the lesion (20 mg at each point) every 7 days for 4 to 12 weeks. Patients received a blood test for toxicity at every cycle. From one of these patients, endoscopic biopsy specimens were taken from gastric cancer before and after injecting 5-FU for immunostaining. A total of five AGC patients participated in this study. For most patients, hemoglobin levels were maintained without transfusions during 5-FU injection, and expression levels of thrombospondin-1 was increased after injection compared to those before injection. Blood test results during 5-FU injection showed no significant change in serum glutamic oxalacetic transaminase/glutamic pyruvic transaminase, total bilirubin, or creatinine level. The results of this study showed the possibility of local peritumor 5-FU injection as a treatment for relieving anemia of patients with gastric cancer.

Risk of colorectal cancer in patients with positive results of fecal immunochemical test performed within 5 years since the last colonoscopy

Background/Aims@#Annual fecal immunochemical tests (FITs) are often repeated within the recommended colonoscopy surveillance intervals. However, it remains unclear whether interval FITs are useful. To answer this question, we assessed the risk of colorectal cancer (CRC) according to the interval from the last colonoscopy to an FIT. @*Methods@#Using the Korean National Cancer Screening Program database, we collected data on patients who underwent FITs in 2011. Patients with positive FIT results were classified into three groups according to their previous colonoscopy interval: 0.5 to 5 years (group 1), 5 to 10 years (group 2), and ≥ 10 years or no colonoscopy (group 3). CRC incidence was defined as CRC diagnosed within 1 year after an FIT. @*Results@#Among 177,660 patients with positive FIT results, the incidence of CRC in groups 1, 2, and 3 was 0.72% (n = 214/29,575), 1.28% (n = 116/9,083), and 3.88% (n = 5,387/139,002), respectively. The age- and sex-adjusted risk for CRC was higher in groups 2 (odds ratio [OR], 1.79; 95% confidence interval [CI], 1.43 to 2.25) and 3 (OR, 5.56; 95% CI, 4.85 to 6.38) than in group 1. Among patients who did and did not undergo a polypectomy during the previous colonoscopy, those in group 2 had a higher rate of CRC than those in group 1 (without polypectomy: 1.15% vs. 0.63%; OR, 1.79; 95% CI, 1.37 to 2.34) (with polypectomy: 2.37% vs. 0.93 %; OR, 2.30; 95% CI, 1.44 to 3.69). @*Conclusion@#In patients with positive FIT results who had undergone a colonoscopy within the past 5 years, the risk of CRC is very low, regardless of whether a polypectomy was performed, suggesting that interval FITs are not useful.

Impact of nonalcoholic fatty liver disease on the risk of metachronous colorectal neoplasia after polypectomy

Background/Aims@#Metabolic syndrome has been reported to be a risk factor for metachronous colorectal neoplasia (CRN). However, the impact of nonalcoholic fatty liver disease (NAFLD), a hepatic manifestation of metabolic syndrome, on the development of metachronous CRN after polypectomy has been rarely examined. We evaluated the association between NAFLD and the development of metachronous CRN after polypectomy. @*Methods@#Asymptomatic subjects who underwent abdominal ultrasonography and endoscopic removal of ≥ 1 adenomas at the index colonoscopy between 2010 and 2014, and had a follow-up surveillance colonoscopy until 2017 were analyzed. @*Results@#Of 6,182 participants, 2,642 (42.7%) had NAFLD at the time of the index colonoscopy. Patients with NAFLD had significantly higher cumulative incidence rates of metachronous overall CRN than those without NAFLD in both men (19.4% vs. 18.2% at 3 years and 49.2% vs. 44.0% at 5 years; p = 0.001) and women (18.7% vs. 10.5% at 3 years and 56.1% vs. 29.8% at 5 years; p < 0.001). Even after adjusting for confounders, NAFLD remained independently associated with an increased risk of metachronous overall CRN in both men (adjusted hazard ratio [HR], 1.17; 95% confidence interval [CI], 1.06 to 1.29) and women (adjusted HR, 1.63; 95% CI, 1.27 to 2.07). Additionally, NAFLD was an independent risk factor for metachronous advanced CRN (ACRN) in women (adjusted HR, 2.61; 95% CI, 1.27 to 5.37). @*Conclusions@#NAFLD is related to an increased risk of metachronous CRN after polypectomy. Especially, women with NAFLD are at an increased risk of developing metachronous ACRN. Our results indicate a possible effect of NAFLD on the pathogenesis of CRN.

Comparison of Long-term Outcomes of Infliximab versus Adalimumab in 1,488 Biologic-Naive Korean Patients with Crohn’s Disease

Background/Aims@#Data on the comparative effectiveness of infliximab (IFX) or adalimumab (ADA) in patients with Crohn’s disease (CD) are rare, particularly for Asian patients. We compared the key clinical outcomes (surgery, hospitalization, and corticosteroid use) of use of these two drugs in biologic-naive Korean patients with CD. @*Methods@#Using National Health Insurance claims, we collected data on patients who were diagnosed with CD and exposed to IFX or ADA between 2010 and 2016. @*Results@#We included 1,488 new users of biologics (1,000 IFX users and 488 ADA users). Over a median follow-up period of 2.1 years after starting biological therapy, no significant differences were found between IFX and ADA users in the risks for surgery (ADA vs IFX: adjusted hazard ratio [aHR], 1.22; 95% confidence interval [CI], 0.81 to 1.84), hospitalization (aHR, 1.02; 95% CI, 0.81 to 1.28), and corticosteroid use (aHR, 0.82; 95% CI, 0.56 to 1.19). These results were unchanged even when only patients who used biologics for over 6 months were analyzed (aHR [95% CI]: surgery, 1.31 [0.82 to 2.11]; hospitalization, 1.02 [0.80 to 1.30]; corticosteroid use, 0.80 [0.54 to 1.18]). Additionally, these results were unchanged in patients treated with biologics as monotherapy or in combination with immunomodulators. @*Conclusions@#In this nationwide population-based study, no significant difference was found in the long-term effectiveness of IFX and ADA in the real-world setting of biologic-naive Korean patients with CD. In the absence of trials to directly compare IFX and ADA, our study indicates that the selection of one of these two biologics can be determined by patient and/or physician preference.

Metabolically Healthy Obesity Is Associated with an Increased Risk of Colorectal Adenoma Occurrence Diagnosed by Surveillance Colonoscopy

Background/Aims@#The risk of recurrence of colorectal adenoma among obese individuals without metabolic abnormalities or in those with metabolically healthy obesity is largely unexplored.Therefore, we longitudinally investigated the risk of adenoma occurrence in individuals undergoing surveillance colonoscopy according to metabolic status and obesity. @*Methods@#This retrospective cohort study included 16,872 Korean adults who underwent their first screening colonoscopy between 2003 and 2012 and who then underwent follow-up colonoscopy until 2017. Participants were categorized into a metabolically healthy nonobese group (reference group), a metabolically healthy obese group, a metabolically abnormal nonobese group, and a metabolically abnormal obese group. Hazard ratios (HRs) for adenoma recurrence compared to the reference group were calculated in each group. @*Results@#During a median follow-up duration of 47.3 months (interquartile range, 35.6 to 58.9 months), 3,673 (21.8%) and 292 (1.73%) participants developed adenoma and advanced adenoma, respectively. When age, sex, smoking, alcohol consumption, family history of colorectal cancer, and baseline adenoma risk were adjusted, the risk of adenoma recurrence was increased in metabolically healthy obese individuals (HR, 1.33; 95% confidence interval [CI], 1.12 to 1.57) and metabolically abnormal obese individuals (HR, 1.18; 95% CI, 1.08 to 1.30) but not in metabolically abnormal nonobese individuals (HR, 1.03; 95% CI, 0.94 to 1.13). @*Conclusions@#In this study, metabolically healthy obese individuals and metabolically abnormal obese individuals exhibited increased risks of occurrence of colorectal adenoma diagnosed by surveillance colonoscopy. This finding implies that obesity itself, even without metabolic abnormalities, is associated with an increased risk of adenoma recurrence.

Risk of colorectal cancer in patients with positive results of fecal immunochemical test performed within 5 years since the last colonoscopy

Background/Aims@#Annual fecal immunochemical tests (FITs) are often repeated within the recommended colonoscopy surveillance intervals. However, it remains unclear whether interval FITs are useful. To answer this question, we assessed the risk of colorectal cancer (CRC) according to the interval from the last colonoscopy to an FIT. @*Methods@#Using the Korean National Cancer Screening Program database, we collected data on patients who underwent FITs in 2011. Patients with positive FIT results were classified into three groups according to their previous colonoscopy interval: 0.5 to 5 years (group 1), 5 to 10 years (group 2), and ≥ 10 years or no colonoscopy (group 3). CRC incidence was defined as CRC diagnosed within 1 year after an FIT. @*Results@#Among 177,660 patients with positive FIT results, the incidence of CRC in groups 1, 2, and 3 was 0.72% (n = 214/29,575), 1.28% (n = 116/9,083), and 3.88% (n = 5,387/139,002), respectively. The age- and sex-adjusted risk for CRC was higher in groups 2 (odds ratio [OR], 1.79; 95% confidence interval [CI], 1.43 to 2.25) and 3 (OR, 5.56; 95% CI, 4.85 to 6.38) than in group 1. Among patients who did and did not undergo a polypectomy during the previous colonoscopy, those in group 2 had a higher rate of CRC than those in group 1 (without polypectomy: 1.15% vs. 0.63%; OR, 1.79; 95% CI, 1.37 to 2.34) (with polypectomy: 2.37% vs. 0.93 %; OR, 2.30; 95% CI, 1.44 to 3.69). @*Conclusion@#In patients with positive FIT results who had undergone a colonoscopy within the past 5 years, the risk of CRC is very low, regardless of whether a polypectomy was performed, suggesting that interval FITs are not useful.

Impact of nonalcoholic fatty liver disease on the risk of metachronous colorectal neoplasia after polypectomy

Background/Aims@#Metabolic syndrome has been reported to be a risk factor for metachronous colorectal neoplasia (CRN). However, the impact of nonalcoholic fatty liver disease (NAFLD), a hepatic manifestation of metabolic syndrome, on the development of metachronous CRN after polypectomy has been rarely examined. We evaluated the association between NAFLD and the development of metachronous CRN after polypectomy. @*Methods@#Asymptomatic subjects who underwent abdominal ultrasonography and endoscopic removal of ≥ 1 adenomas at the index colonoscopy between 2010 and 2014, and had a follow-up surveillance colonoscopy until 2017 were analyzed. @*Results@#Of 6,182 participants, 2,642 (42.7%) had NAFLD at the time of the index colonoscopy. Patients with NAFLD had significantly higher cumulative incidence rates of metachronous overall CRN than those without NAFLD in both men (19.4% vs. 18.2% at 3 years and 49.2% vs. 44.0% at 5 years; p = 0.001) and women (18.7% vs. 10.5% at 3 years and 56.1% vs. 29.8% at 5 years; p < 0.001). Even after adjusting for confounders, NAFLD remained independently associated with an increased risk of metachronous overall CRN in both men (adjusted hazard ratio [HR], 1.17; 95% confidence interval [CI], 1.06 to 1.29) and women (adjusted HR, 1.63; 95% CI, 1.27 to 2.07). Additionally, NAFLD was an independent risk factor for metachronous advanced CRN (ACRN) in women (adjusted HR, 2.61; 95% CI, 1.27 to 5.37). @*Conclusions@#NAFLD is related to an increased risk of metachronous CRN after polypectomy. Especially, women with NAFLD are at an increased risk of developing metachronous ACRN. Our results indicate a possible effect of NAFLD on the pathogenesis of CRN.

Metabolically Healthy Obesity Is Associated with an Increased Risk of Colorectal Adenoma Occurrence Diagnosed by Surveillance Colonoscopy

Background/Aims@#The risk of recurrence of colorectal adenoma among obese individuals without metabolic abnormalities or in those with metabolically healthy obesity is largely unexplored.Therefore, we longitudinally investigated the risk of adenoma occurrence in individuals undergoing surveillance colonoscopy according to metabolic status and obesity. @*Methods@#This retrospective cohort study included 16,872 Korean adults who underwent their first screening colonoscopy between 2003 and 2012 and who then underwent follow-up colonoscopy until 2017. Participants were categorized into a metabolically healthy nonobese group (reference group), a metabolically healthy obese group, a metabolically abnormal nonobese group, and a metabolically abnormal obese group. Hazard ratios (HRs) for adenoma recurrence compared to the reference group were calculated in each group. @*Results@#During a median follow-up duration of 47.3 months (interquartile range, 35.6 to 58.9 months), 3,673 (21.8%) and 292 (1.73%) participants developed adenoma and advanced adenoma, respectively. When age, sex, smoking, alcohol consumption, family history of colorectal cancer, and baseline adenoma risk were adjusted, the risk of adenoma recurrence was increased in metabolically healthy obese individuals (HR, 1.33; 95% confidence interval [CI], 1.12 to 1.57) and metabolically abnormal obese individuals (HR, 1.18; 95% CI, 1.08 to 1.30) but not in metabolically abnormal nonobese individuals (HR, 1.03; 95% CI, 0.94 to 1.13). @*Conclusions@#In this study, metabolically healthy obese individuals and metabolically abnormal obese individuals exhibited increased risks of occurrence of colorectal adenoma diagnosed by surveillance colonoscopy. This finding implies that obesity itself, even without metabolic abnormalities, is associated with an increased risk of adenoma recurrence.

Impact of Smoking on Human Natural Killer Cell Activity: A Large Cohort Study

Some studies have reported a decrease in the natural killer (NK) cell activity in smokers. However, large-scale data on the relationshipbetween NK cell activity and smoking are unavailable. A cross-sectional study was performed on 12,249 asymptomatic examineeswho underwent an NK cell activity test, between January 2016 and May 2017. The test quantitated the amount of interferon-γsecreted into the plasma by NK cells, using a patented stimulatory cytokine. The mean age of the study population was 39.1 years,and the proportions of “never”, “former”, and “current” smokers were 65.5%, 20.9%, and 13.6%, respectively. Current smokers (1,422pg/mL) had a lower median level of NK cell activity than never smokers (1,504 pg/mL, P = 0.039) and former smokers (1,791 pg/mL, P < 0.001). Among current smokers, NK cell activity decreased with increase in the number of cigarettes smoked among currentsmokers (median, 1,537, 1,429, and 1,175 pg/mL at <10, 10-19, and ≥ 20 pack-years, respectively; P < 0.001). Additionally, itdecreased linearly with increasing quartiles of cotinine levels (median, 1,707, 1,636, 1,348, and 1,292 pg/mL at cotinine levels < 292,292-879, 880-1,509, and ≥ 1,510 ng/mL, respectively; r = –0.122, P < 0.001). NK cell activity was lower in current smokers. It alsodecreased with an increase in the number of cigarettes smoked, and it was negatively correlated with cotinine levels among currentsmokers. Our findings indicate a clear relationship between smoking and decreased NK cell activity.

Similar Clinical Outcomes of Early andLate Anti-TNF Initiation for Ulcerative Colitis:A Nationwide Population-Based Study

Purpose@#The optimal timing of anti-tumor necrosis factor (anti-TNF) initiation in patients with ulcerative colitis (UC) remainsunclear. Very little is known about the clinical outcomes after the early versus late initiation of anti-TNF therapy, especially inAsian UC patients. Here we aimed to assess whether earlier anti-TNF treatment initiation results in favorable clinical outcomes inKorean UC patients. @*Materials and Methods@#Using the Korean National Health Insurance claims database, we studied patients who were diagnosedwith UC and received anti-TNF therapy for more than 6 months between 2010 and 2016. Using a Cox proportional hazard model,clinical outcomes including colectomy, UC-related emergency room (ER) visits, UC-related hospitalizations, and the need for corticosteroidswere compared between early (≤2 years of diagnosis) and late (>2 years of diagnosis) initiators of anti-TNF therapy. @*Results@#Among 17167 UC patients, 698 patients who received anti-TNF therapy for more than 6 months were included (420 infliximab,242 adalimumab, and 36 golimumab). Of the 698 patients, 299 (42.8%) initiated anti-TNF therapy within 2 years of diagnosis.There were no significant differences in the risk of colectomy [adjusted hazard ratio (aHR), 0.41; 95% confidence interval(CI), 0.04–3.90], ER visits (aHR, 0.98; 95% CI, 0.50–1.92), hospitalization (aHR, 0.76; 95% CI, 0.57–1.01), and corticosteroid use(aHR, 1.04; 95% CI, 0.71–1.50) between early and late initiators of anti-TNF therapy. @*Conclusion@#Patients receiving early anti-TNF therapy had similar clinical outcomes to those of late initiators, suggesting that earlyanti-TNF therapy initiation offers little benefit in patients with UC.

Changes in Abdominal Obesity Affect the Risk of Metachronous Advanced Colorectal Neoplasia Development after Polypectomy

Purpose@#The impact of changes in body mass index and waist circumference on the development of metachronous colorectal neoplasia (CRN) after polypectomy has rarely been examined. We evaluated the association between changes in overall/abdominal obesity and metachronous CRN risk. @*Materials and Methods@#We studied patients who underwent ≥1 adenoma removal and surveillance colonoscopy. Patients were classified into the following four groups based on the changes in overall obesity from index to follow-up colonoscopy: non-obesity persisted (group 1), obesity to non-obesity (group 2), non-obesity to obesity (group 3), and obesity persisted (group 4). Patients were also divided into another four groups based on similar changes in abdominal obesity (groups 5–8). @*Results@#The number of patients in groups 1, 2, 3, and 4 was 5074, 457, 643, and 3538, respectively, and that in groups 5, 6, 7, and 8 was 4229, 538, 656, and 2189, respectively. Group 4 had a significantly higher risk of metachronous CRN compared to groups 1 and 2. However, metachronous advanced CRN (ACRN) risk was not different among groups 1, 2, 3, and 4. Metachronous CRN risk in group 8 (abdominal obesity persisted) was higher than that in groups 5 (non-abdominal obesity persisted) and 7 (non-abdominal obesity to abdominal obesity), and tended to be higher than that in group 6 (abdominal obesity to non-abdominal obesity). Additionally, group 8 had a significantly higher risk of metachronous ACRN compared to groups 5, 6, and 7. @*Conclusion@#Changes in obesity affected the metachronous CRN risk. In particular, changes in abdominal obesity affected the metachronous ACRN risk.

Impact of early anti-TNF use on clinical outcomes in Crohn’s disease: a nationwide population-based study

Background/Aims@#The optimal timing for initiation of anti-tumor necrosis factor (TNF) therapy in Crohn’s disease (CD) is still debated. Little is known about the clinical outcomes of early versus late administration of anti-TNF agents, especially in Asian CD patients. We aimed to evaluate the impact of early anti-TNF therapy on clinical outcomes in Korean CD patients. @*Methods@#Using the Korean National Health Insurance Claims database, we collected data on patients diagnosed with CD who received anti-TNF therapy for more than 6 months between 2010 and 2016. Early initiation of anti-TNF therapy was defined as those starting infliximab or adalimumab therapy within 1 year of diagnosis. The following outcomes were assessed using a Cox proportional hazard model: abdominal surgery, CD-related emergency room (ER) visit, CD-related hospitalization, and new corticosteroid use. @*Results@#Among 1,207 patients, 609 were early initiators of anti-TNF. Late anti-TNF initiation (> 1 year after diagnosis) was associated with increased risk of surgery (adjusted hazard ratio [aHR], 1.64; 95% confidence interval [CI], 1.05 to 2.55) and tended to be associated with increased risk of ER visit (aHR, 1.38; 95% CI, 0.99 to 1.94). However, there were no significant differences in the risk of hospitalization and corticosteroid use between early and late initiators. @*Conclusions@#Early anti-TNF therapy among Korean CD patients within 1 year of diagnosis was associated with better clinical outcomes than late therapy, such as lower surgery and ER visit rates. Our results suggest that aggressive medical intervention in the early stages of CD may potentially change the course of this disease.

Comparison of Real-World Outcomes of Infliximab versus Adalimumab in Biologic-Naïve Korean Patients with Ulcerative Colitis: A Population-Based Study

Age at menarche and risk of colorectal adenoma

BACKGROUND/AIMS@#Limited data are available regarding the association between age at menarche and the risk of colorectal adenoma. Therefore, we aimed to evaluate the relationship between reproductive factors including age at menarche and the risk of colorectal adenoma.@*METHODS@#A cross-sectional study was performed on asymptomatic female subjects who underwent colonoscopy between 2010 and 2014 as part of a comprehensive health screening program in Korea. The association between reproductive factors including age at menarche and the presence of adenomas was assessed using multivariate logistic regression analysis.@*RESULTS@#Among 32,620 asymptomatic female subjects, the proportion of patients with menarche at 10 to 11, 12 to 13, 14 to 15, 16 to 17, and 18 to 19 years of age was 4.1%, 31.7%, 45.4%, 14.9%, and 4.0%, respectively. Age at menarche was not significantly associated with the risk of any adenoma (adjusted odds ratio [AOR], 0.99; 95% confidence interval [CI], 0.97 to 1.02; p = 0.500) or advanced adenoma (AOR, 0.98; 95% CI, 0.91 to 1.04; p = 0.468) after adjusting for confounding factors. Age at menarche was not significantly associated with the risk of adenoma even among similar age groups. In addition, parity, use of female hormones, and menopause were not associated with the risk of adenoma.@*CONCLUSIONS@#Age at menarche, parity, use of female hormones, and menopause were not significantly associated with the risk of colorectal adenoma. Our findings indicate that reproductive factors including age at menarche do not affect the development of colorectal adenoma.

Appropriate Surveillance Interval after Colonoscopic Polypectomy in Patients Younger than 50 Years

BACKGROUND: Current postpolypectomy surveillance guidelines are based on studies in patients aged ≥50 years. Equal application of the guidelines in patients aged < 50 years may be unreasonable. We aimed to determine an appropriate surveillance interval after adenoma removal in patients aged < 50 years. METHODS: We studied 10,013 patients who underwent ≥ 1 adenoma removal and follow-up colonoscopy. The cumulative risk of metachronous advanced colorectal neoplasia (ACRN) was compared among the eight groups based on age (30–39, 40–44, 45–49 and ≥ 50 years) and baseline adenoma characteristics (low- [LRA] and high-risk adenoma [HRA]). RESULTS: The risk of metachronous ACRN in patients aged 30–39 and 40–44 years with HRA was comparable to that in those aged ≥ 50 years with LRA (P = 0.839 and P = 0.381, respectively). However, the risk in those aged 45–49 years with HRA was higher than in those aged ≥ 50 years with LRA (P = 0.003), and the risk was not significantly different from that in those aged ≥ 50 years with HRA (P = 0.092). Additionally, the 5-year cumulative risk in those aged 45–49 years with LRA was not significantly different from that in those aged ≥ 50 years with LRA. CONCLUSION: The postpolypectomy surveillance interval can be extended up to 5 years in patients aged 30–44 years with HRA, similar to those aged ≥ 50 years with LRA. However, the interval in patients aged 45–49 years with HRA and LRA should be 3 and 5 years, respectively, similar to those aged ≥ 50 years.

Development and validation of a scoring system for advanced colorectal neoplasm in young Korean subjects less than age 50 years

BACKGROUND/AIMS: Colorectal cancer incidence among patients aged ≤50 years is increasing. This study aimed to develop and validate an advanced colorectal neoplasm (ACRN) screening model for young adults aged <50 years in Korea. METHODS: This retrospective cross-sectional study included 59,575 consecutive asymptomatic Koreans who underwent screening colonoscopy between 2003 and 2012 at a single comprehensive health care center. Young Adult Colorectal Screening (YCS) score was developed as an optimized risk stratification model for ACRN using multivariate analysis and was internally validated. The predictive power and diagnostic performance of YCS score was compared with those of Asia-Pacific Colorectal Screening (APCS) and Korean Colorectal Screening (KCS) scores. RESULTS: 41,702 and 17,873 subjects were randomly allocated into the derivation and validation cohorts, respectively, by examination year. ACRN prevalence was 0.9% in both cohorts. YCS score comprised sex, age, alcohol, smoking, obesity, glucose metabolism abnormality, and family history of CRC, with score ranges of 0 to 10. In the validation cohort, ACRN prevalence was 0.6% in the low-risk tier (score, 0–4), 1.5% in the moderate-risk tier (score, 5–7), and 3.4% in the high-risk tier (score, 8–10). ACRN risk increased 2.5-fold (95% confidence interval [CI], 1.8–3.4) in the moderate-risk tier and 5.8-fold (95% CI, 3.4–9.8) in the high-risk tier compared with the low-risk tier. YCS score identified better balanced accuracy (53.9%) than APCS (51.5%) and KCS (50.7%) scores and had relatively good discriminative power (area under the curve=0.660). CONCLUSIONS: YCS score based on clinical and laboratory risk factors was clinically effective and beneficial for predicting ACRN risk and targeting screening colonoscopy in adults aged <50 years.

Should asymptomatic young men with iron deficiency anemia necessarily undergo endoscopy?

BACKGROUND/AIMS: There has been no evidence for the necessity of endoscopy in asymptomatic young men with iron deficiency anemia (IDA). To determine whether endoscopy should be recommended in asymptomatic young men with IDA, we compared the prevalence of gastrointestinal (GI) lesions between young men (< 50 years) with IDA and those without IDA. METHODS: We conducted a case-control study on asymptomatic young men aged < 50 years who underwent both esophagogastroduodenoscopy (EGD) and colonoscopy as part of a health checkup between 2010 and 2014. RESULTS: Of 77,864 participants, 128 (0.16%) had IDA and 512 subjects without IDA were matched for several variables including age. Young men with IDA had a significantly higher proportion of colorectal cancer (CRC) (0.8% vs. 0.0%, p = 0.045), villous adenoma (0.8% vs. 0.0%, p = 0.045), and inflammatory bowel disease (IBD; 2.3% vs. 0.4%, p = 0.025) than those without IDA. Additionally, the prevalence of advanced colorectal neoplasia (ACRN) tended to be higher in subjects with IDA than in those without IDA (3.1% vs. 1.0%, p = 0.084). The prevalence of significant lower GI lesions including ACRN and IBD was higher in subjects with IDA than in those without IDA (5.5% vs. 1.4%, p = 0.011). Regarding upper GI lesions, a positive association with IDA was observed only for gastric ulcer (4.7% vs. 1.0%, p = 0.011). CONCLUSIONS: GI lesions including CRC, villous adenoma, IBD, and gastric ulcer were more common in asymptomatic young men with IDA. Our results suggest that EGD and particularly colonoscopy should be recommended even in asymptomatic young men with IDA.