Inflammatory bowel disease in Korea: epidemiological, genomic, clinical, and therapeutic characteristics

Clinical Features of Paediatric Inflammatory Epidermolysis Bullosa Acquisita: A Case Series Study

Epidermolysis bullosa acquisita (EBA) rarely develops in childhood. This study retrospectively recruited paediatric patients with EBA (age ≤ 16 years), diagnosed by clinical and histopathological features and results of immunofluorescence, immunoblotting and enzyme-linked immunosorbent assay (ELISA), and reviews their clinical manifestations, histopathology, immunological features, and responses to various treatments. All 7 included patients presented with inflammatory EBA. Among them, 3 had a bullous pemphigoid-like phenotype. Pathologically, in addition to dermal-epidermal blistering, in all patients, the distribution of neutrophils was superficial perivascular or interstitial, or in the dermal papilla. Mixed neutrophils and eosinophils were detected in 2 of the 3 patients with bullous pemphigoid-like phenotypes. In addition to treatment with glucocorticoids, dapsone was administered in 4 patients, while thalidomide and sulfasalazine were administered in 1 patient. All patients responded to the these therapies. Relapse was mainly due to reduction and cessation of glucocorticoids. In conclusion, EBA in childhood may be unique, and thus distinct from its adult counterpart. Specific treatment and follow-up protocols are required for therapy of this rare autoimmune skin disease in children.

Longitudinal trends in direct costs and healthcare utilization ascribable to inflammatory bowel disease in the biologic era: a nationwide, population-based study

BACKGROUND AND AIM

Biologic-era data regarding the direct cost and healthcare utilization of inflammatory bowel disease at the population level are limited, especially in Asia. Thus, we aimed to investigate the nationwide prevalence, direct cost, and healthcare utilization of inflammatory bowel disease in Korea in a recent 10-year period.

METHODS

Using the Korean National Health Insurance claim data from 2008 to 2017, we investigated all prescription medications and their associated direct costs, hospitalizations, and outpatient visits. We also estimated the nationwide prevalence of inflammatory bowel disease using population census data.

RESULTS

The estimated inflammatory bowel disease prevalence significantly increased from 108.8/100 000 in 2008 to 140.4/100 000 in 2017. The overall annual costs for inflammatory bowel disease and the healthcare cost per capita increased from $24.5 million (in US dollars) to $105.1 million and from $458.4 to $1456.6 million, respectively (both P < 0.001). Whereas the ratio of outpatient costs increased from 35.3% to 69.4%, that of outpatient days remained steady. The total annual medication cost and proportion rose from $13.3 million to $76.8 million and from 54.2% to 73.3%, respectively, mainly due to the increasing antitumor necrosis factor cost, from $1.5 million to $49.3 million (from 11.1% to 64.1% of the total annual drug cost and from 6.3% to 46.9% of the total annual cost).

CONCLUSIONS

We observed increasing trends in the prevalence, direct costs, and healthcare utilization of inflammatory bowel disease in Korea in recent years. The attributable cost was mainly driven by rising expenditures on antitumor necrosis factor medications.

Oenanthe javanica Ethanolic Extract Alleviates Inflammation and Modifies Gut Microbiota in Mice with DSS-Induced Colitis

Oenanthe javanica, commonly known as water dropwort, has long been used to treat acute and chronic hepatitis, abdominal pain, alcohol hangovers, and inflammation in various traditional medicine systems in Asia. However, whether O. javanica has beneficial effects on colitis-induced intestinal damage remains elusive. This study tested the hypothesis that O. javanica has anti-inflammatory and antioxidant activities in mice with dextran sulfate sodium (DSS)-induced colitis. First, treatment of O. javanica ethanol extract (OJE) inhibited the production of inflammatory cytokines in lipopolysaccharide-affected macrophages. Second, in mice with DSS-induced colitis, OJE administration reduced pathological damage to the colon while alleviating weight gain and decreasing colon length, including inflammation and mucosal necrosis. In addition, OJE significantly (p < 0.01) restricted the activation of nuclear factor-κB (NF-κB) and the secretion of pro-inflammatory mediators and increased the expression of Nrf2-phase 2 antioxidant enzymes. The results of 16S rRNA gene sequencing workflows for taxonomic assignment analysis confirmed that the diversity (richness and evenness) of fecal microbiota was markedly elevated in the OJE group. OJE administration reduced the abundance of Proteobacteria including Escherichia and increased the abundance of the genus Muribaculum. These results suggested that OJE exerts beneficial effects on inflammation and gut microbial composition in a mouse model of colitis.

The application of Tong-fu therapeutic method on ulcerative colitis: A systematic review and meta-analysis for efficacy and safety of rhubarb-based therapy

Background: Tong-fu therapeutic method (TFTM) is a traditional Chinese medicine treatment method for ulcerative colitis, which is a novel treatment strategies and have purgative effect. As the most representative medicinal of TFTM, Rhubarb has been reported to have a therapeutic impact on ulcerative colitis by regulating intestinal flora, anti-inflammation, and improving intestinal microcirculation. Although rhubarb has been widely used in Chinese medicine for the treatment of ulcerative colitis, the appropriate protocol is still demanded to its rational use in clinic, which promoted to evaluate the efficacy and safety for rhubarb-based therapy on ulcerative colitis.

Method: Clinical trials were searched through PubMed, Cochrane Library, Web of Science, Excerpta Medica Database, Chinese National Knowledge Infrastructure, WAN FANG Database, Chinese Scientific Journal Database, and Chinese Biomedical Literature Database. The subgroup analyses were performed with three groups: medication, course of treatment, and route of administration. The statistical analyses were performed on Review Manager software (version 5.4.1).

Results: A total of 2, 475 patients in 30 original studies were analyzed in this article. It was found that rhubarb-based therapy could increase clinical efficacy and reduce the recurrence rate. Subgroup analyses showed that rhubarb-based therapy was more effective than 5-aminosalicylic acid or sulfasalazine alone. In addition, the hypercoagulable state of ulcerative colitis could be ameliorated by decreasing platelet (PLT) and fibrinogen (FIB), and increasing prothrombin time (PT) significantly. Moreover, C-reaction protein (CRP), tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-8, and IL-1β expression were significantly reduced, while IL-10 production was increased, which mediated the alleviation of intestinal inflammation stress.

Conclusion: Rhubarb-based therapy could effectively improve ulcerative colitis. Of note, the rhubarb-based medicinal formulas combined with 5-ASA or SASP are more effective than the 5-ASA or SASP alone. In addition, although rhubarb has side effect, the results of our analysis showed that rhubarb-based therapy did not exhibit significant side effects. This means it has a high safety profile in clinical use. Moreover, the use of rhubarb-based therapy is recommend to use within 1–13 weeks or 3 months via administered orally or by enema, which is contributes to ensure the curative effect and avoid its toxic and side effects. As an important case of TFTM, rhubarb-based therapy provides evidence for the practical application of TFTM.

Evaluation of nutritional status using bioelectrical impedance analysis in patients with inflammatory bowel disease

BACKGROUND/AIMS

Nutritional status influences quality of life among patients with inflammatory bowel disease (IBD), although there is no clear method to evaluate nutritional status in this setting. Therefore, this study examined whether bioelectrical impedance analysis (BIA) could be used to evaluate the nutritional status of patients with IBD.

METHODS

We retrospectively analyzed data from 139 Korean patients with IBD who were treated between November 2018 and November 2019. Patients were categorized as having active or inactive IBD based on the Harvey-Bradshaw index (a score of ≥5 indicates active Crohn's disease) and the partial Mayo scoring index (a score of ≥2 indicates active ulcerative colitis). BIA results and serum nutritional markers were analyzed according to disease activity.

RESULTS

The mean patient age was 45.11±17.71 years. The study included 47 patients with ulcerative colitis and 92 patients with Crohn's disease. Relative to the group with active disease (n=72), the group with inactive disease (n=67) had significantly higher values for hemoglobin (P<0.001), total protein (P<0.001), and albumin (P<0.001). Furthermore, the group with inactive disease had higher BIA values for body moisture (P=0.047), muscle mass (P=0.046), skeletal muscle mass (P=0.042), body mass index (P=0.027), and mineral content (P=0.034). Moreover, the serum nutritional markers were positively correlated with the BIA results.

CONCLUSIONS

Nutritional markers evaluated using BIA were correlated with serum nutritional markers and inversely correlated with disease activity. Therefore, we suggest that BIA may be a useful tool that can help existing nutritional tests monitor the nutritional status of IBD patients.

Efficacy and Safety of Probiotics Combined With Traditional Chinese Medicine for Ulcerative Colitis: A Systematic Review and Meta-Analysis

Background: The combination of probiotics and traditional Chinese medicine (TCM) is a prospective therapy for ulcerative colitis (UC), and its efficacy and safety need to be urgently evaluated.

Objective: This study aims to comprehensively assess the efficacy and safety of probiotics combined with TCM for the treatment of UC.

Methods: The Pubmed, EMBASE, Cochrane library, China Academic Journals (CNKI), Wan-fang database, Chinese biomedical literature service system (CBM), and Chinese Science and Technology Journals (CQVIP) were searched. Subgroup analysis were designed in accordance with different control drugs, treatment courses, and types of probiotics. The Review Manager software (version 5.4.1) was utilized for statistical analysis.

Results: 14 original studies containing 1,154 patients were analyzed and showed that probiotics with TCM was more effective than 5-aminosalicylic acid (5-ASA), probiotics or TCM used individually. Moreover, probiotics combined with TCM could inhibit the intestinal inflammation, reduce the recurrence rate and the incidence of adverse events. The subgroup analysis showed that a mixture of different probiotics was more effective than a single strain.

Conclusion: It is suggested that probiotics combined with TCM could effectively control clinical symptoms, inhibit intestinal inflammatory response, and finally slow down the disease progress and reduce the disease recurrence with less adverse events. The mixture of different probiotics used in conjunction with individually tailored TCM is a potential clinical strategy for UC.

Epidemiology and diagnosis of inflammatory bowel diseases

Background: Over the past three decades, inflammatory bowel diseases (IBD) have been rapidly increasing in the African, South American, and Asian countries, including Korea. However, in Korea, the public awareness of IBD remains low, and diagnostic delay is not uncommon due to the physicians' lack of clinical experience. It is essential to understand the trends and regional differences in the epidemiology of IBD for proper diagnosis and treatment.Current Concepts: Although lower than those of the West, the prevalence and incidence of IBD in Korea rank among the highest in Asia and are steadily increasing. In the past 10 years, the prevalence of IBD has almost doubled, while its incidence has decreased gradually. As compared to Western IBD patients, Korean patients have higher proportion of proctitis in ulcerative colitis, male predominance, more ileocolonic involvement, and higher incidence of perianal fistula in Crohn disease. There is no single gold standard for the diagnosis of IBD. Thus, diagnosis can be made by clinical evaluation, including a detailed history taking, physical examination, and a combination of endoscopic, radiologic, laboratory, and histologic findings.Discussion and Conclusion: Population-based studies have revealed the current trends and characteristics of the epidemiology of IBD in Korea. Continued education and development of diagnostic tools will help clinicians to diagnose IBD accurately and differentiate it from other diseases such as intestinal tuberculosis.

Efficacy and safety of vedolizumab in Crohn's disease in patients from Asian countries in the GEMINI 2 study

BACKGROUND/AIMS

The efficacy and safety of vedolizumab in moderate-to-severely active Crohn's disease (CD) were demonstrated in the GEMINI 2 study (NCT00783692). This post-hoc exploratory analysis aimed to assess the efficacy and safety of vedolizumab in the subgroup of patients from Asian countries.

METHODS

During the induction phase (doses at day 1, 15), clinical remission, enhanced clinical response, and change in C-reactive protein at 6 weeks; during the maintenance phase, clinical remission, enhanced clinical response, glucocorticoid-free remission and durable clinical remission at 52 weeks, were the efficacy outcomes of interest. Efficacy and safety of vedolizumab compared to placebo were assessed in Asian countries (Hong Kong, India, Malaysia, Singapore, South Korea, and Taiwan) using descriptive analyses.

RESULTS

During the induction phase, in Asian countries (n = 51), 14.7% of the vedolizumab-treated patients achieved clinical remission at week 6 compared to none with placebo (difference, 14.7%; 95% confidence interval, 15.8%-43.5%). In non-Asian countries (n = 317), the remission rate at week 6 with vedolizumab was 14.5%. During maintenance, in Asian countries, clinical remission rates at 52 weeks with vedolizumab administered every 4 weeks, vedolizumab administered every 8 weeks and placebo were 41.7%, 36.4%, and 0%, respectively; while enhanced clinical response rates were 41.7%, 63.6%, and 42.9%, respectively. During induction, 39.7% of patients with vedolizumab experienced an adverse event compared to 58.8% of patients with placebo, and vedolizumab was generally well-tolerated.

CONCLUSIONS

This post-hoc analysis demonstrates the treatment effect and safety of vedolizumab in moderateto-severely active CD in patients from Asian countries.

Effect of Thiopurine on Potential Surgical Intervention in Crohn’s Disease in Korea: Results from the CONNECT Study

Objectives: The incidence of Crohn's disease and the number of associated surgeries are increasing in Korea. This study investigated the effect of azathioprine/6-mercaptopurine (6-MP) and TNF-α antagonists on abdominal and perianal surgery in Korean patients with Crohn's disease. Design: A retrospective cohort study. Setting: Data from the Crohn's Disease Clinical Network and Cohort (CONNECT) were used. Patients with confirmed Crohn's disease between 1982 and 2008 from 32 hospitals in the Republic of Korea were enrolled. The effect of azathioprine/6-MP on abdominal and perianal surgery was analysed using logistic regression analysis adjusting for age and sex. Participants: In total, 1161 Crohn's disease patients were included in the Republic of Korea in the surgery (n = 462, male = 339, female = 123) and control groups (n = 699, male = 484, female = 215). Results: In total, 1161 patients were selected, with 462 patients who underwent abdominal (n = 245) or perianal surgery (n = 217). The preoperative usage rates of azathioprine/6-MP were 18.8% and 65.1% (p < 0.0001) in the surgery and control groups, respectively. The preoperative usage rates of TNF-α antagonists were 7.1% and 23.3% (p < 0.0001) in the surgery and control groups, respectively. A multivariate analysis revealed that the preoperative use of azathioprine/6-MP had an odds ratio of 0.094 for all surgeries (95% confidence interval [CI]: 0.070-0.127, p < 0.0001), 0.131 for abdominal surgery (95% CI: 397-1.599, p < 0.0001), and 0.059 for perianal surgery (95% CI: 0.038-0.091, p < 0.0001). The preoperative use of TNF-α antagonists had an odds ratio of 0.225 for all surgeries (95% CI: 0.151-0.335, p < 0.0001), 0.403 for abdominal surgery (95% CI: 0.261-0.623, p < 0.0001), and 0.064 for perianal surgery (95% CI: 0.026-0.160, p < 0.001). Strengths of this study: The study presents new evidence of the reduced risk of surgery following azathioprine use in Crohn's disease patients. Limitations of this study (1) This was not a controlled prospective study. (2) There was a selection bias specific to the CONNECT cohort. (3) The combination or sequential use of azathioprine/6-MP and TNF-α antagonists was not excluded. Conclusion: Azathioprine/6-MP is significantly associated with a reduced risk of abdominal and perianal surgery in Korean patients with Crohn's disease.

Incidence of suboptimal response to tumor necrosis factor antagonist therapy in inflammatory bowel disease in newly industrialised countries: The EXPLORE study

BACKGROUND

Incidence of inflammatory bowel disease (IBD) is increasing in newly industrialised countries (NICs); however, data on suboptimal response to anti-tumor necrosis factor (anti-TNF) agents are limited.

OBJECTIVES

To assess incidence and indicators of suboptimal response to first anti-TNF therapy in IBD patients in NICs.

METHODS

A chart review was conducted in ten countries from Asia-Pacific (APAC), Latin America (LatAm), and Russia and the Middle East (RME) regions among patients diagnosed with ulcerative colitis (UC) or Crohn's disease (CD), initiating anti-TNF therapy in 2010-2015. The cumulative incidence of suboptimal response to anti-TNF therapy was assessed using the following indicators: dose escalation or discontinuation, augmentation with non-biologic therapy, IBD-related hospitalization, or surgery.

RESULTS

The study included 1,674 patients (570 UC; 1,104 CD). At 24 months, 32.9% of UC (APAC: 45.1%; LatAm: 38.2%; RME: 23.8%) and 41.2% of CD patients (APAC: 54.1%; LatAm: 42.5%; RME: 29.5%) had experienced suboptimal response. The most frequent first indicator was non-biologic therapy augmentation in LatAm (41.7%), IBD-related hospitalization in RME (UC: 50.7%; CD:37.3%) and in APAC for CD (39.1%), and anti-TNF discontinuation in APAC for UC (38.3%).

CONCLUSION

Suboptimal response to anti-TNF agents is common in IBD patients in NICs. Observed regional differences in the incidence and indicators may reflect local practice and anti-TNF restrictions in IBD management.

NCT REGISTRATION NUMBER

NCT03090139.

Effect of Age on the Initiation of Biologic Agent Therapy in Patients With Inflammatory Bowel Disease: Korean Common Data Model Cohort Study

BACKGROUND

The Observational Health Data Sciences and Informatics (OHDSI) network is an international collaboration established to apply open-source data analytics to a large network of health databases, including the Korean common data model (K-CDM) network.

OBJECTIVE

The aim of this study is to analyze the effect that age at diagnosis has on the prognosis of inflammatory bowel disease (IBD) in Korea using a CDM network database.

METHODS

We retrospectively analyzed the K-CDM network database from 2005 to 2015. We transformed the electronic medical record into the CDM version 5.0 used in OHDSI. A worsened IBD prognosis was defined as the initiation of therapy with biologic agents, including infliximab and adalimumab. To evaluate the effect that age at diagnosis had on the prognosis of IBD, we divided the patients into an early-onset (EO) IBD group (age at diagnosis <40 years) and a late-onset (LO) IBD group (age at diagnosis ≥40 years) with the cutoff value of age at diagnosis as 40 years, which was calculated using the Youden index method. We then used the logrank test and Cox proportional hazards model to analyze the effect that age at diagnosis (EO group vs LO group) had on the prognosis in patients with IBD.

RESULTS

A total of 3480 patients were enrolled. There was 2017 patients with ulcerative colitis (UC) and 1463 with Crohn's disease (CD). The median follow up period was 109.5 weeks. The EO UC group was statistically significant and showed less event-free survival (ie, experiences of biologic agents) than the LO UC group (P<.001). In CD, the EO CD group showed less event-free survival (ie, experiences of biologic agents) than the LO CD group. In the Cox proportional hazard analysis, the odds ratio (OR) of the EO UC group on experiences of biologic agents compared with the LO UC group was 2.3 (95% CI 1.3-3.8, P=.002). The OR of the EO CD group on experiences of biologic agents compared with the LO CD group was 5.4 (95% CI 1.9-14.9, P=.001).

CONCLUSIONS

The EO IBD group showed a worse prognosis than the LO IBD group in Korean patients with IBD. In addition, this study successfully verified the CDM model in gastrointestinal research.

Trends and risk factors of elderly-onset Crohn’s disease: A nationwide cohort study

BACKGROUND

The incidence of inflammatory bowel disease (IBD) is increasing in Asia. Numerous risk factors associated with IBD development have been investigated.

AIM

To investigate trends and environmental risk factors of Crohn’s disease (CD) diagnosed in persons aged ≥ 40 years in South Korea.

METHODS

Using the National Health Insurance Service database, a total of 14060821 persons aged > 40 years who underwent national health screening in 2009 were followed up until December 2017. Patients with newly diagnosed CD were enrolled and compared with non-CD cohort. CD was identified according to the International Classification of Diseases 10th revision and the rare/intractable disease registration program codes from the National Health Insurance Service database. The mean follow-up periods was 7.39 years. Age, sex, diabetes, hypertension, smoking, alcohol consumption, regular exercise, body mass index, anemia, chronic kidney disease (CKD) and dyslipidemia were adjusted for in the multivariate analysis model.

RESULTS

During the follow-up, 1337 (1.33/100000) patients developed CD. Men in the middle-aged group (40-64 years) had a higher risk than women [adjusted hazard ratio (aHR) 1.46, 95% confidence interval (CI): 1.29-1.66]; however, this difference tended to disappear as the age of onset increases. In the middle-aged group, patients with a history of smoking [aHR 1.46, 95%CI: 1.19-1.79) and anemia (aHR 1.85, 95%CI: 1.55-2.20) had a significantly higher CD risk. In the elderly group (age, ≥ 65 years), ex-smoking and anemia also increased the CD risk (aHR 1.68, 95%CI: 1.22-2.30) and 1.84 (95%CI: 1.47-2.30, respectively). Especially in the middle-aged group, those with CKD had a statistically elevated CD risk (aHR 1.37, 95%CI: 1.05-1.79). Alcohol consumption and higher body mass index showed negative association trend with CD incidence in both of the age groups. [Middle-aged: aHR 0.77 (95%CI: 0.66-0.89) and aHR 0.73 (95%CI: 0.63-0.84), respectively] [Elderly-group: aHR 0.57 (95%CI: 0.42-0.78) and aHR 0.84 (95%CI 0.67-1.04), respectively]. For regular physical activity and dyslipidemia, negative correlation between CD incidences was proved only in the middle-aged group [aHR 0.88 (95%CI: 0.77-0.89) and aHR 0.81 (95%CI: 0.68-0.96), respectively].

CONCLUSION

History of cigarette smoking, anemia, underweight and CKD are possible risk factors for CD in Asians aged > 40 years.

Two-year delay in ulcerative colitis diagnosis is associated with anti-tumor necrosis factor alpha use

BACKGROUND

Ulcerative colitis (UC) is an uncommon inflammatory bowel disease (IBD). However, its incidence has recently increased in South Korea. Moreover, UC diagnoses are frequently delayed, and the relationship between diagnostic delay and UC prognosis has not been extensively studied in South Korean patients.

AIM

To identify meaningful diagnostic delay affecting UC prognosis and to evaluate risk factors associated with diagnostic delay in South Korean patients.

METHODS

Medical records of 718 patients with UC who visited the outpatient clinic of six university hospitals in South Korea were reviewed; 167 cases were excluded because the first symptom date was unknown. We evaluated the relationship between the prognosis and a diagnostic delay of 3, 6, 12, 18, and 24 mo by comparing the prognostic factors [anti-tumor necrosis factor (TNF)-α use, admission history due to acute flare-ups, frequent admission due to flare-ups, surgery associated with UC, and the clinical remission state at the latest follow-up] at each diagnostic interval.

RESULTS

The mean diagnostic interval was 223.3 ± 483.2 d (median, 69 d; 75^th percentile, 195 d). Among the prognostic factors, anti-TNFα use was significantly increased after a diagnostic delay of 24 mo. Clinical risk factors predictive of a 24-mo diagnostic delay were age < 60 years at diagnosis [odd ratio (OR) = 14.778, 95% confidence interval (CI): 1.731-126.121], smoking history (OR = 2.688, 95%CI: 1.239-5.747, P = 0.012), and misdiagnosis of hemorrhoids (OR = 11.066, 95%CI: 3.596-34.053). Anti-TNFα use was associated with extensive UC at diagnosis (OR = 3.768, 95%CI: 1.860-7.632) and 24-mo diagnostic delay (OR = 2.599, 95%CI: 1.006-4.916).

CONCLUSION

A diagnostic delay > 24 mo was associated with increased anti-TNFα use. Age < 60 years at diagnosis, smoking history, and misdiagnosis of hemorrhoids were risk factors for delayed diagnosis.

Total Glycosides of Peony Protects Against Inflammatory Bowel Disease by Regulating IL-23/IL-17 Axis and Th17/Treg Balance

Inflammatory bowel disease (IBD) is a group of autoimmune diseases, including ulcerative colitis and Crohn’s disease, characterized by nonspecific inflammation in the gut. Total glycoside of peony (TGP) has been widely used for treatment of autoimmune diseases because of its pharmacological effects. However, it is lack of depth in whether TGP regulate T helper 17 cell (Th17) / T regulatory cell (Treg) immune balance or interleukin 23 (IL-23) / IL-17 axis to achieve the goal of treating IBD. Hence, the aim of this study was to investigate the effects of TGP on experimental colitis mice and the related mechanisms. In the present study, we demonstrated that administration of TGP effectively attenuates colonic inflammation of TNBS-induced colitis mice, mainly reflected in significantly improved clinical parameters, reduced inflammatory response and myeloperoxidase (MPO) activity, even stronger systemic immune ability and effective improvement of Th17/Treg immune disorders. In addition, there was a stronger immunosuppressive ability in a positive cluster of differentiation 4 (CD4[Formula: see text]) T-lymphocytes from the TGP treated mouse colon, characterized by the inhibition of high levels of inflammatory factors and increased regulatory T cells. Importantly, high-dose TGP has similar therapeutic effects as salicylazosulfapyridine (SASP) on IBD treatment. The potential mechanisms might be, at least in part, related to the adjustment of imbalance of Th17/Treg cells and the inhibition of IL-23/IL17 inflammatory signal axis.

Association of Perianal Fistulas with Clinical Features and Prognosis of Crohn's Disease in Korea: Results from the CONNECT Study

Background/Aims

The disease course and factors associated with poor prognosis in Korean patients with Crohn’s disease (CD) have not been fully determined. The aim of this study was to explore potential associations between the clinical characteristics and long-term outcomes of CD and perianal fistulas in a Korean population.

Methods

The retrospective Crohn’s Disease Clinical Network and Cohort (CONNECT) study enrolled patients diagnosed with CD between July 1982 and December 2008 from 32 hospitals. Those followed for <12 months were excluded. Clinical outcomes were CD-related surgery and complications, including nonperianal fistulas, strictures, and intra-abdominal abscesses.

Results

The mean follow-up period was 8.77 years (range, 1.0 to 25.8 years). A total of 1,193 CD patients were enrolled, of whom 465 (39.0%) experienced perianal fistulas. Perianal fistulizing CD was significantly associated with younger age, male gender, CD diagnosed at primary care clinics, and ileocolonic involvement. Both nonperianal fistulas (p=0.034) and intra-abdominal abscesses (p=0.020) were significantly more common in CD patients with perianal fistulas than in those without perianal fistulas. The rates of complicated strictures and CD-related surgery were similar between the groups. Independently associated factors of nonperianal fistulas were perianal fistulas (p=0.015), female gender (p=0.048), CD diagnosed at referral hospital (p=0.003), and upper gastrointestinal (UGI) involvement (p=0.001). Furthermore, perianal fistulas (p=0.048) and UGI involvement (p=0.012) were independently associated with the risk of intra-abdominal abscesses.

Conclusions

Perianal fistulas predicted the development of nonperianal fistulas and intra-abdominal abscesses in Korean CD patients. Therefore, patients with perianal fistulizing CD should be carefully monitored for complicated fistulas or abscesses.

Renal involvement in children and adolescents with inflammatory bowel disease

PURPOSE

The incidence of inflammatory bowel disease (IBD) is rapidly increasing, and several reports have described the renal complications of IBD. We sought to evaluate the clinical manifestations of renal complications in children with IBD in order to enable early detection and prompt treatment of the complications.

METHODS

We retrospectively reviewed the medical records of 456 children and adolescents aged <20 years who had been diagnosed with IBD since 2000. We analyzed patient age, sex, medication use, IBD disease activity, and clinical manifestations of renal symptoms.

RESULTS

Our study comprising 456 children with IBD included 299 boys (65.6%) and 157 girls (34.4%). The study included 346 children with Crohn disease and 110 children with ulcerative colitis. The incidence of kidney-related symptoms was 14.7%, which was significantly higher than that in normal children. We observed 26 children (38.8%) with isolated hematuria, 30 children (44.8%) with isolated proteinuria, and 11 children (16.4%) with hematuria and concomitant proteinuria. A renal biopsy was performed in 7 children. Histopathological examination revealed immunoglobulin A nephropathy in 5 children (71.4%). All children presented with mild disease and well-controlled disease activity of IBD.

CONCLUSION

Children with IBD are more likely to show kidney-related symptoms than healthy children and adolescents are. Therefore, regular screening of urine and evaluation of renal function in such children are necessary for early detection of renal complications.

Incidence of psoriasiform diseases secondary to tumour necrosis factor antagonists in patients with inflammatory bowel disease: a nationwide population-based cohort study

BACKGROUND

There are increasing reports of paradoxical psoriasiform diseases secondary to anti-tumour necrosis factor (TNF) agents.

AIMS

To determine the risks of paradoxical psoriasiform diseases secondary to anti-TNF agents in patients with inflammatory bowel disease (IBD).

METHODS

A nationwide population study was performed using the Korea National Health Insurance Claim Data. A total of 50 502 patients with IBD were identified between 2007 and 2016. We compared 5428 patients who were treated with any anti-TNF agent for more than 6 months (anti-TNF group) and 10 856 matched controls who had never taken anti-TNF agents (control group).

RESULTS

Incidence of psoriasis was significantly higher in the anti-TNF group (36.8 per 10 000 person-years) compared to the control group (14.5 per 10 000 person-years) (hazard ratio [HR] 2.357, 95% confidence interval [CI] 1.668-3.331). Palmoplantar pustulosis (HR 9.355, 95% CI 2.754-31.780) and psoriatic arthritis (HR 2.926, 95% CI 1.640-5.218) also showed higher risks in the anti-TNF group. In subgroup analyses, HRs for psoriasis by IBD subtype were 2.549 (95% CI 1.658-3.920) in Crohn's disease and 2.105 (95% CI 1.155-3.836) in ulcerative colitis. Interestingly, men and younger (10-39 years) patients have significantly higher risks of palmoplantar pustulosis (HR 19.682 [95% CI 3.867-100.169] and HR 14.318 [95% CI 2.915-70.315], respectively), whereas women and older (≥40 years) patients showed similar rates between the two groups.

CONCLUSIONS

The risks of psoriasiform diseases are increased by anti-TNF agents in patients with IBD. Among psoriasiform diseases, the risk of palmoplantar pustulosis shows the biggest increase particularly in male and younger patients.

Is top-down therapy a more effective alternative to conventional step-up therapy for Crohn's disease?

The management of Crohn's disease involves immunosuppressive protocols in a step-up approach that progresses through a therapeutic pyramid with several tiers of medication. Medications at the top are considered more potent but present greater risk. A new top-down approach to therapy inverts this procedure, using top-tier drugs for initial treatment. A critical appraisal of the current literature relating to top-down therapy was performed to evaluate its merit. A literature search was conducted on PubMed, Ovid, and PubMed Central to identify studies of the efficacy of top-down therapy. Papers were appraised critically using the Scottish Intercollegiate Guidelines Network score to evaluate current evidence for the use of top-down therapy. Nineteen studies were identified, including six randomized controlled trials, thirteen cohort studies, and two cost-benefit studies. Early combined therapy involving both biologics and immunomodulators was found to be effective at improving patient outcomes; however, early biologics alone were not shown to have a clear benefit over step-up therapy. Likewise, the early use of immunomodulators alone showed inconsistent results with respect to efficacy in terms of both remission and surgical outcomes. Evidence for application in pediatric populations was also inconclusive. The cost-benefit analyses found that top-down therapy merits investigation, as it proved to be economical given current data. Top-down therapy has the potential of being a viable alternative to step-up therapy, but further studies are needed to determine the most appropriate patients to receive this treatment.

Epidemiology of Inflammatory Bowel Disease in India: The Great Shift East

BACKGROUND

Inflammatory bowel disease (IBD), once considered to be a Western disease, is increasingly being reported from India and other Asian countries. The present review summarizes epidemiology and disease characteristics of IBD in India with reference to other Asian countries and the West.

SUMMARY

India is projected to have one of the highest disease burden of IBD across the globe. The overall genetic risk and microbial signature in Indian IBD patients are similar to those of patients in the West as demonstrated by the similar incidence of IBD in second-generation Indian immigrants and matching perturbations in the structural and functional component of gut microbiota in Indian studies. The concept of the hygiene hypothesis continues to remain controversial with Indian studies demonstrating contradictory findings. The disease characteristics, long-term outcomes including the risk of colorectal cancer, and the effect of pregnancy on IBD and vice versa in Indian patients with IBD are in general similar with few differences. Unlike patients in the West, very few Indian patients have a positive family history.

KEY MESSAGE

The Indian disease pattern is going through a phase of epidemiological transition with a surge in the incidence of IBD. The epidemiology and disease characteristics of IBD mirror the patterns observed in the West.

Development of a Novel Predictive Model for the Clinical Course of Crohn's Disease: Results from the CONNECT Study

BACKGROUND

A considerable number of patients with Crohn's disease (CD) develop irreversible intestinal damage, although the early administration of immunomodulatory or biological therapies might prevent this. The aims of our study were to develop and validate a novel predictive model that can be used to predict the risk of surgical intervention in Korean patients with CD.

METHODS

The prognostic model was derived from the multicenter longitudinal CONNECT (CrOhn's disease cliNical NEtwork and CohorT) study cohort consisting of 1338 patients with CD, who were split into training and validation sets. The Korean Crohn's Disease Prediction (KCDP) model was developed with the training set data using the Cox proportional hazards model and multivariate analysis, and was then validated using the validation set.

RESULTS

A total of 1271 patients with CD were analyzed. During the follow-up period of 10,188 patient-years (median 7.1 yrs), 361 patients (28.4%) underwent CD-related surgery. Age at diagnosis, jejunal involvement, initial disease behavior, and perianal disease at diagnosis were associated with a poor prognosis and included in the KCDP model, which showed a modest discrimination ability with a Harrel's c-index of 0.731 at 5 years, and was well calibrated (Hosmer-Lemeshow χ = 8.230, P = 0.511).

CONCLUSIONS

This is the first validated surgery risk prediction model for Korean patients with CD; it provides accurate individualized estimates of the probability of surgery using clinical parameters collected at diagnosis. This model might guide appropriate patient selection for the early intensive treatment of CD.

Impact of inflammatory bowel disease on daily life: an online survey by the Korean Association for the Study of Intestinal Diseases

BACKGROUND/AIMS

Inflammatory bowel disease (IBD) is a chronic disabling gastrointestinal disorder that diminishes the quality of life of the affected individuals. Limited data are available regarding the impact of IBD on the daily life of Koreans.

METHODS

Self-administered, computer-aided, internet-based questionnaires were distributed to members of a Korean patient organization for IBD from March to April 2013, by the Korean Association for the Study of Intestinal Diseases.

RESULTS

A total of 599 patients with IBD (387 with Crohn's disease [CD] and 212 with ulcerative colitis [UC]) were enrolled. The majority of patients (81%) expressed feelings of fatigue, weakness, and being worn out in their daily lives during times of flare; this percentage was reduced to 61% during remission. Respondents were absent from work or school for an average period of 18 days because of illness, within the first 6 months; the majority of respondents (64%) felt stressed about their absence. Forty-six percent of the respondents reported having received unfair comments at work, or having suffered discrimination. Forty-seven percent of the respondents felt that IBD had negatively affected their income and earnings. Compared with patients with UC, those with CD reported a more frequent negative impact of IBD on work, or more economic burden. More than half of the respondents (61%) reported that IBD had prevented them from making or keeping friends.

CONCLUSIONS

IBD significantly impacts daily life, including work, education, and social relationships. Treatment that addresses the full spectrum of life of a patient would be more effective.

Factors Associated with Anxiety and Depression in Korean Patients with Inactive Inflammatory Bowel Disease

BACKGROUND/AIMS

Psychological distress is highly prevalent in patients with inflammatory bowel disease (IBD). We evaluated the disease characteristics and socioeconomic factors associated with anxiety and depression in Korean patients with quiescent IBD.

METHODS

In total, 142 IBD patients (67 with Crohn's disease [CD] and 75 with ulcerative colitis [UC]) completed self-report questionnaires, including the Hospital Anxiety and Depression Score, the Modified Morisky Adherence Scale-8, the socioeconomic deprivation score, and the Crohn's and Colitis Knowledge Score questionnaires.

RESULTS

In the CD group, 30 patients (44%) were anxious, and 10 patients (15%) were depressed; in the UC group, 31 patients (41%) were anxious, and 18 patients (24%) were depressed. Using multivariate analysis, in the CD group, socioeconomic deprivation was associated with anxiety (p=0.03), whereas disease duration (p=0.04) and socioeconomic deprivation (p=0.013) were associated with depression. In the UC group, there was no significant independent predictor of anxiety and/or depression; however, low income tended to be associated with depression (p=0.096).

CONCLUSIONS

Despite clinical remission, a significant number of IBD patients present with anxiety and depression. IBD patients in remission, particularly those who are socioeconomically deprived, should be provided with appropriate psychological support.

Ophthalmologic manifestations in patients with inflammatory bowel disease

BACKGROUND/AIMS

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), has been reported to have various ophthalmologic manifestations. The aim of this study was to evaluate the prevalence of ophthalmologic manifestations associated with IBD in Korea.

METHODS

Sixty-one patients were examined between May 2013 and October 2014. We performed complete ophthalmologic examinations.

RESULTS

Findings included 36 patients with CD and 25 with UC. The mean age of the patients was 34±16 years and disease duration was 45.3±23.9 months. Ophthalmologic manifestations were positive in 44 cases. Primary complication was diagnosed in 5 cases, as follows; iritis in 2 cases, episcleritis in one case, iritis with optic neuritis in 1 case, and serous retinal detachment in 1 case, without secondary complications. The most common coincidental complication was dry eye syndrome (DES), in 35 patients (57.4%). The prevalence of DES in the control group was 21.3%. The proportion of DES in patients with IBD was significantly higher than in the control group (P=0.002).

CONCLUSIONS

Ophthalmologic manifestations were high (72.1%) in IBD patients. Clinically significant primary ocular inflammation occurred in 8.2% of patients. The most common complication was DES. There was a higher rate of DES in patients with IBD compared to the control group. Evaluation of the eye should be a routine component in patients with IBD.

Clinical Efficacy of Beclomethasone Dipropionate in Korean Patients with Ulcerative Colitis

PURPOSE

Our aim was to evaluate the efficacy and safety of oral beclomethasone dipropionate (BDP) in Korean patients with ulcerative colitis (UC).

MATERIALS AND METHODS

The medical records of patients with active UC who were treated with BDP were retrospectively reviewed. Partial Mayo Clinic score (pMS) was calculated to determine disease activity. After 4 weeks of therapy, clinical remission, clinical response, and response failure rates were evaluated. Clinical remission was defined as a post-treatment pMS of 0 or 1, clinical response as a decrease of two of three points in pMS and >30% from baseline, and response failure as a lack of clinical response. Also, we considered that clinical remission was included in clinical response.

RESULTS

Between July 2013 and April 2015, 95 patients with UC received BDP therapy at our institution (median age, 44 years; range, 12-81 years). After 4 weeks of therapy, clinical remission and clinical response rates were 50.5% and 73.7%, respectively. Mean change of pMS before and after BDP therapy was 2.4. There was no significant side effect reported. In multivariate analysis, disease activity was the only factor associated with a favorable response. Clinical remission rate was significantly higher in the mild disease activity group (66.7%) than that in the moderate or severe disease activity group (41.9%) (p=0.024).

CONCLUSION

BDP is efficacious in inducing a clinical response or remission in Korean patients with UC. Patients with mild UC were more likely to be in remission than those with moderate or severe UC after receiving BDP for 4 weeks. BDP exhibited a good safety profile.

Patients with perianal Crohn's disease have poor disease outcomes after primary bowel resection

BACKGROUND AND AIM

The presence of perianal disease in Crohn's disease patients is one of the factors of postoperative recurrence. The aim of this study is to evaluate long-term prognosis of perianal Crohn's disease patients in Asian.

METHODS

Patients with Crohn's disease who had undergone surgical bowel resection were divided into two groups according to the presence of perianal lesion. We monitored the occurrences of abdominal and/or perianal reoperation and readmission due to disease flare-up.

RESULTS

The 132 patients included in the study were divided into 2 groups, those with perianal disease (45 patients, 34.1%) and those without perianal disease (87 patients, 65.9%). Patients with perianal disease was younger in age (33.8 years versus 39.8 years, p = 0.015) and had been diagnosed as CD at a younger age (21.9 years versus 28.6 years, p = 0.005) than patients without perianal disease. Patients with perianal disease showed more extra-intestinal manifestation than patients without perianal disease (8 versus 3, p = 0.008). Reoperation was required in 46 (44.8%) patients during the follow-up period. The presence of perianal disease independently increased the risk of reoperation [hazard ratio (HR), 3.112; confidence interval (CI), 1.707-5.675]. Furthermore, patients with perianal disease had increasing risks of abdominal reoperation (HR 1.978; 95% CI, 1.034-3.784).

CONCLUSIONS

Patients with Crohn's disease and perianal lesions had a higher risk of reoperation. Considering these findings, physicians should consider aggressive and early top down therapy for patients with perianal Crohn's disease.

Diagnosis of inflammatory bowel disease in Asia: the results of a multinational web-based survey in the 2(nd) Asian Organization for Crohn's and Colitis (AOCC) meeting in Seoul

Background/Aims

As the number of Asian patients with inflammatory bowel disease (IBD) has increased recently, there is a growing need to improve IBD care in this region. This study is aimed at determining how Asian countries are currently dealing with their IBD patients in terms of diagnosis.

Methods

A questionnaire was designed by the organizing committee of Asian Organization for Crohn's and Colitis, for a multinational web-based survey conducted between March 2014 and May 2014.

Results

A total of 353 Asian medical doctors treating IBD patients responded to the survey (114 in China, 88 in Japan, 116 in Korea, and 35 in other Asian countries). Most of the respondents were gastroenterologists working in an academic teaching hospital. While most of the doctors from China, Japan, and Korea use their own national guidelines for IBD diagnosis, those from other Asian countries most commonly adopt the European Crohn's Colitis Organisation's guideline. Japanese doctors seldom adopt the Montreal classification for IBD. The most commonly used activity scoring system for ulcerative colitis is the Mayo score in all countries except China, whereas that for Crohn's disease (CD) is the Crohn's Disease Activity Index. The most available tool for small-bowel evaluation in CD patients differs across countries. Many physicians administer empirical anti-tuberculous medications before the diagnosis of CD.

Conclusions

The results of this survey demonstrate that Asian medical doctors have different diagnostic approaches for IBD. This knowledge would be important in establishing guidelines for improving the care of IBD patients in this region.

Association of tumor necrosis factor-α and -β gene polymorphisms in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a complex, multifactorial, chronic inflammatory disorder of the gastrointestinal tract in which immune dysregulation caused by genetic and/or environmental factors plays an important role. The aim of this case–control study was to evaluate the association of tumor necrosis factor-alpha (TNF-α) (308) and -β (+252) polymorphisms with susceptibility of IBD. A total of 379 Saudi subjects including 179 IBD patients (ulcerative colitis (UC) =84 and Crohn’s disease (CD) =95) and 200 age- and sex-matched healthy controls were recruited. TNF-α and TNF-β genes were amplified using an amplification refractory mutation systems polymerase chain reaction methodology to detect TNF-α (−308) and -β (+252) polymorphisms. The frequency of the GA genotype of TNF-α (−308G/A) was higher, and the frequencies of the GG and AA genotypes were significantly lower in IBD patients compared with those in controls, indicating that genotype GA-positive individuals are susceptible to IBD and that the GG and AA genotypes exert a protective effect. The frequency of allele A of TNF-α (−308G/A) was significantly higher and that of allele G was lower in IBD patients compared with those in controls, indicating an association of allele A with IBD risk in Saudi patients. On stratification of IBD patients into UC and CD, an almost similar pattern was noticed in both the groups. The results of TNF-β (+252A/G) polymorphisms showed a significant increase in the frequency of the GG genotype in IBD patients, suggesting a positive association of GG genotype with IBD risk. On stratification of IBD patients into UC and CD, the genotype GG of TNF-β was associated with susceptibility risk to UC but not CD. The frequencies of alleles and genotypes of both TNF-α and-β polymorphisms are not affected by sex or type of IBD (familial or sporadic). TNF-α (−308G/A) and TNF-β (+252A/G) polymorphisms are associated with risk of developing IBD in Saudi population.

Deep resequencing of 131 Crohn's disease associated genes in pooled DNA confirmed three reported variants and identified eight novel variants

OBJECTIVE

Genome wide association studies (GWAS) and meta-analyses for Crohn's disease (CD) have not fully explained the heritability of CD, suggesting that additional loci are yet to be found and that the known loci may contain high effect rare risk variants that have thus far gone undetected by GWAS. While the cost of deep sequencing remains too high to analyse many samples, targeted sequencing of pooled DNA samples allows the efficient and cost effective capture of all variations in a target region.

DESIGN

We performed pooled sequencing in 500 Korean CD cases and 1000 controls to evaluate the coding exon and 5' and 3' untranslated regions of 131 CD associated genes. The identified genetic variants were validated using genotyping in an independent set of 500 CD cases and 1000 controls.

RESULTS

Pooled sequencing identified 30 common/low single nucleotide variants (SNVs) in 12 genes and 3 rare SNVs in 3 genes. Our results confirmed a significant association of CD with the following previously reported risk loci: rs3810936 in TNFSF15 (OR=1.83, p<2.2×10(-16)), rs76418789 in IL23R (OR=0.47, p=1.14×10(-8)) and rs2241880 in ATG16L1 (OR=1.30, p=5.28×10(-6)). In addition, novel loci were identified in TNFSF8 (rs3181374, OR=1.53, p=1.03×10(-14)), BTNL2 (rs28362680, OR=1.47, p=9.67×10(-11)), HLA-DQA2 (rs3208181, OR=1.36, p=4.66×10(-6)), STAT3 (rs1053004, OR=1.29, p=2.07×10(-5)), NFKBIA (rs2273650, OR=0.80, p=3.93×10(-4)), NKX2-3 (rs888208, OR=0.82, p=6.37×10(-4)) and DNAH12 (rs4462937, OR=1.13, p=3.17×10(-2)). A novel rare SNV, rs200735402 in CARD9, was shown to have a protective effect (OR=0.09, p=5.28×10(-5)).

CONCLUSIONS

Our deep resequencing of 131 CD associated genes confirmed 3 reported risk loci and identified 8 novel risk loci for CD in Koreans, providing new insights into the genetic architecture of CD.

Efficacy of Adalimumab in Korean Patients with Crohn's Disease

BACKGROUND/AIMS

Adalimumab is effective for both remission induction and the maintenance of Crohn's disease (CD) in Western countries. We evaluated the efficacy of adalimumab in the conventional step-up treatment approach for CD in Korea.

METHODS

We retrospectively reviewed 62 patients with CD who were treated with adalimumab. Their Crohn's disease activity index (CDAI) was measured at weeks 4, 8, and 52. Clinical remission was defined as a CDAI score <150. Induction and maintenance outcomes were analyzed.

RESULTS

Forty-one patients (66.1%) achieved a reduction of 70 CDAI points at week 8. Among them, 28 (45.2%) achieved clinical remission at week 8, 20 (32.3%) maintained remission at week 52. The absence of prior anti-tumor necrosis factor (TNF) therapy and Montreal classification L1 at baseline predicted clinical remission at week 8 in the multivariate logistic regression analysis. In the Cox proportional hazards model, the hazard ratio for the secondary loss of response during maintenance therapy after clinical remission induction was significantly higher in patients who showed initial mild CDAI severity or Montreal classification A3.

CONCLUSIONS

In our study, anti-TNF therapy-naive and Montreal classification L1 were associated with adalimumab efficacy as induction therapy in CD. Further studies are warranted to determine the prognostic factors for the long-term response after adalimumab therapy.

Crohn's disease prognosis and early immunomodulator therapy: Results from the CONNECT study

BACKGROUND

It is unknown whether the treatment initiating time of immunomodulators such as thiopurines affects the course of Crohn's disease (CD). We evaluated the efficacy of early immunomodulator therapy (EIT) on the prognosis of patients with CD.

METHODS

We retrospectively analyzed 1157 patients with CD who were enrolled in the CrOhn's disease cliNical NEtwork and CohorT study and received immunomodulator therapy. The patients were divided into an EIT group and a conventional therapy group based on whether immunomodulators were initiated within six months after being diagnosed with CD. We compared the rates of intestinal surgery, bowel complications, and hospitalization because of CD between the groups.

RESULTS

Patient age at diagnosis and sex were not significantly different between the two groups. The mean duration of follow-up was 105.8 ± 51.5 months. A Kaplan-Meier analysis identified that the EIT group was superior to the conventional therapy group in terms of delaying surgery (P = 0.017). In multivariate analysis, EIT was an independent predicting factor associated with delaying the onset of complications (P = 0.050). Patients were divided into two groups based on the year of CD diagnosis: from 1982 to 1999 (A) and from 2000 to 2008 (B). In group A, the time from diagnosis to the start of immunomodulatory therapy was longer (P < 0.001), and the time to first intestinal surgery was shorter than group B (P = 0.002).

CONCLUSIONS

The early use of immunomodulators was associated with a good prognosis as defined by a need for surgery and the occurrence of complications in CD in our multicenter study.

Clinical Factors and Disease Course Related to Diagnostic Delay in Korean Crohn's Disease Patients: Results from the CONNECT Study

Diagnostic delay frequently occurs in Crohn's disease (CD) patients because of diagnostic limitations. However, diagnostic delay and its related factors remain poorly defined. Therefore, we aimed to identify the predictors associated with diagnostic delay and to evaluate the impact of diagnostic delay on clinical course in a Korean CD patient cohort. We performed a multicenter retrospective analysis of 1,047 CD patients registered in the Crohn's Disease Clinical Network and Cohort study in Korea. The mean interval of diagnostic delay was 16.0 ± 33.1 months. Multivariate analysis showed that older age at diagnosis (≥40 years) (p = 0.014), concomitant upper gastrointestinal (UGI) disease (p = 0.012) and penetrating disease behavior at diagnosis (p = 0.001) were positively associated with long diagnostic delay (≥18 months). During the longitudinal follow-up, long diagnostic delay was independently predictive of further development of intestinal stenosis (hazard ratio [HR], 1.43; 95% confidence interval [CI], 1.07-1.93; p = 0.017), internal fistulas (HR, 1.62; 95% CI, 1.12-2.33; p = 0.011), and perianal fistulas (HR, 1.38; 95% CI, 1.06-1.80; p = 0.016). However, as for the risk of abscess formation, bowel perforation, and CD-related abdominal surgery, no significant association with diagnostic delay was observed. Older age at diagnosis, UGI involvement, and penetrating behavior are associated with long diagnostic delay in Korean CD patients. Moreover, diagnostic delay is associated with an increased risk of CD-related complications such as intestinal stenosis, internal fistulas, and perianal fistulas.

Infliximab versus Cyclosporine Treatment for Severe Corticosteroid-Refractory Ulcerative Colitis: A Korean, Retrospective, Single Center Study

BACKGROUND/AIMS

In patients with corticosteroid-refractory ulcerative colitis (UC), cyclosporine or infliximab may be added to the treatment regimen to induce remission. Here, we aimed to compare the efficacy of cyclosporine and infliximab.

METHODS

Between January 1995 and May 2012, the medical records of 43 patients with corticosteroid-refractory UC who received either infliximab or cyclosporine as a rescue therapy at a tertiary care hospital in Korea were reviewed.

RESULTS

Among the 43 patients, 10 underwent rescue therapy with cyclosporine and the remaining 33 patients received infliximab. A follow-up of 12 months was completed for all patients. The colectomy rate at 12 months was 30% and 3% in the cyclosporine and the infliximab groups, respectively (p=0.034). However, the Cox proportional hazard model indicated that the treatment of rescue therapy was not an independent associate factor for preventing colectomy (p=0.164). In the subgroup analysis, infliximab with azathioprine was superior to cyclosporine for preventing colectomy (hazard ratio of infliximab with azathioprine compared with cyclosporine only, 0.073; 95% confidence interval, 0.008 to 0.629).

CONCLUSIONS

No difference between infliximab and cyclosporine with respect to preventing colectomy was noted. However, infliximab with azathioprine may be more effective than cyclosporine alone for preventing colectomy.

Use of Thiopurines in Inflammatory Bowel Disease: A Consensus Statement by the Korean Association for the Study of Intestinal Diseases (KASID)

BACKGROUND/AIMS

For decades, thiopurines have been the mainstay of inflammatory bowel disease (IBD) treatment and will play an important role in the future. However, complex metabolism and various side effects limit the use of these potent drugs in clinical practice. The Korean Association for the Study of Intestinal Diseases developed a set of consensus statements with the aim of guiding clinicians on the appropriate use of thiopurines in the management of IBD.

METHODS

Sixteen statements were initially drafted by five committee members. The quality of evidence and classification of recommendation were assessed according to the Grading of Recommendations Assessment, Development and Evaluation system. The statements were then circulated to IBD experts in Korea for review, feedback, and then finalized and accepted by voting at the consensus meeting.

RESULTS

The consensus statements comprised four parts: (1) pre-treatment evaluation and management strategy, including value of thiopurine S-methyltransferase screening, dosing schedule, and novel biomarkers for predicting thiopurine-induced leukopenia; (2) treatment with thiopurines with regards to optimal duration of thiopurine treatment and long-term outcomes of combination therapy with anti-tumor necrosis factors; (3) safety of thiopurines, especially during pregnancy and lactation; and (4) monitoring side effects or efficacy of therapy using biomarkers.

CONCLUSIONS

Thiopurines are an effective treatment option for patients with IBD. Management decisions should be individualized according to the risk of relapse and adverse events.

Inflammatory Bowel Disease Cohort Studies in Korea: Present and Future

Inflammatory bowel disease (IBD) is defined as a chronic and relapsing inflammatory disorder of the intestine. Intestinal inflammation in IBD has been proposed to be attributable to the interplay between microbial, genetic, environmental, and immunological factors. The incidence and prevalence rates of IBD are rapidly increasing apparently in other parts of the world, with dramatic increases especially in East Asia. Generally, cohort studies are useful for estimating the incidence, prevalence, natural course, prognosis, and risk factors of diseases. In particular, cohort studies performed in Western countries have well described the prevalence, risk factors, and natural course of IBD and investigated its genetic pathophysiology. However, the outcomes of IBD cohort studies performed in Korea are not as persuasive as those of Western studies because of the relatively low prevalence of IBD and short follow-up periods of the cohorts in Korea. Despite this critical limitation, members of the Korean Association for the Study of Intestinal Diseases have demonstrated outstanding results. Some unique features of IBD patients in Korea are well demonstrated, such as thiopurine-induced leukopenia or risks of opportunistic tuberculosis infection in patients receiving tumor necrosis factor-α inhibitors. In this review, the present authors summarized the key points of the results of the cohort studies performed in Korea and explored future perspectives.

The clinical characteristics of patients with free perforation in Korean Crohn's disease: results from the CONNECT study

BACKGROUND

Free perforation is the most severe and debilitating complication associated with Crohn's disease (CD), and it usually requires emergency surgery. The aim of this study was to evaluate the incidence of free perforation among Korean patients with CD.

METHODS

The CrOhn's disease cliNical NEtwork and CohorT (CONNECT) study was conducted nationwide in Korea, and patients who were diagnosed with CD between 1982 and 2008 were included in this retrospective study. We investigated the incidence of free perforation among these patients and their clinical characteristics.

RESULTS

A total of 1346 patients were analyzed and 88 patients (6.5%) were identified with free perforation in CD. The mean age of the free perforation group was 31.8 ± 13.0 years, which was significantly higher than that of the non-perforated group (27.5 ± 12.1 years) (p = 0.004). Free perforation was the presenting sign of CD in 46 patients (52%). Of the 94 perforations that were present in 88 patients, 81 involved the ileum. Multivariate logistic regression analysis determined that free perforation was significantly associated with being aged ≥ 30 years at diagnosis (OR 2.082, p = 0.002) and bowel strictures (OR 1.982, p = 0.004). The mortality rate in the free perforation group was significantly higher (4.5%) than that in the non-perforated group (0.6%) (p < 0.001).

CONCLUSION

The incidence of free perforation in Korean patients with CD was 6.5%. Being aged ≥ 30 years at CD diagnosis and bowel strictures were significant risk factors associated with free perforation.

Genetic association of apolipoprotein E polymorphisms with inflammatory bowel disease

AIM: To study the association of apolipoprotein E (APOE) polymorphisms with the susceptibility of inflammatory bowel disease (IBD) in Saudi patients.

METHODS: APOE genotyping was performed to evaluate the allele and genotype frequencies in 378 Saudi subjects including IBD patients with ulcerative colitis (n = 84) or Crohn’s disease (n = 94) and matched controls (n = 200) using polymerase chain reaction and reverse-hybridization techniques.

RESULTS: The frequencies of the APOE ε2 allele and ε2/ε3 and ε2/ε4 genotypes were significantly higher in IBD patients than in controls (P < 0.05), suggesting that the ε2 allele and its heterozygous genotypes may increase the susceptibility to IBD. On the contrary, the frequencies of the ε3 allele and ε3/ε3 genotype were lower in IBD patients as compared to controls, suggesting a protective effect of APOE ε3 for IBD. The prevalence of the ε4 allele was also higher in the patient group compared to controls, suggesting that the ε4 allele may also increase the risk of IBD. Our results also indicated that the APOE ε4 allele was associated with an early age of IBD onset. No effect of gender or type of IBD (familial or sporadic) on the frequency distribution of APOE alleles and genotypes was noticed in this study.

CONCLUSION: APOE polymorphism is associated with risk of developing IBD and early age of onset in Saudi patients, though further studies with a large-size population are warranted.

Extraintestinal manifestations of inflammatory bowel disease and intestinal tuberculosis: Frequency and relation with disease phenotype

BACKGROUND

Extraintestinal manifestations (EIMs) in inflammatory bowel disease (IBD) including ulcerative colitis (UC) and Crohn's disease (CD), as well as intestinal tuberculosis (ITB) from Asia, are underreported. We, therefore, describe the prevalence of EIMs in Indian IBD and ITB patients and study their relationship with disease extent and severity in IBD.

METHODS

This retrospective single-center study included all IBD and ITB patients evaluated from January 2005 to July 2012. Disease profile and frequencies of arthropathies (peripheral and central) and ocular (episcleritis, iritis/uveitis), oral (aphthous stomatitis), skin (erythema nodosum, pyoderma gangrenosum, psoriasis), hepatobiliary (primary sclerosing cholangitis), and thromboembolic manifestations were analyzed.

RESULTS

Of 1,652 patients (1146 UC, 303 CD, 203 ITB), frequency of any EIM was 33.2 %, 38.3 %, and 14.3 % in UC, CD, and ITB patients, respectively. Thromboembolism was more common among UC patients with pancolitis than proctitis (p < 0.001) and left-sided colitis (p = 0.02). Primary sclerosing cholangitis was seen in 0.4 % UC patients. Steroid-dependent UC patients had higher frequency of any EIM, peripheral arthropathy, or thromboembolism than patients with no or infrequent steroid requirement (p < 0.05). Peripheral arthropathy (p = 0.02), erythema nodosum (p = 0.01), and aphthous stomatitis (p = 0.004) were more common with CD than with UC patients. Patients with colonic CD had higher frequency of peripheral arthropathy, any EIM, and multiple EIMs than ileal or ileocolonic disease (p < 0.05). Relative to ITB, CD patients had higher frequencies of peripheral arthropathy (p < 0.001), aphthous stomatitis (p = 0.01), any EIM (p < 0.001), and multiple EIMs (p < 0.001).

CONCLUSIONS

In Indian IBD and ITB patients, EIMs appear to be related to disease severity in UC and disease location in CD and are significantly more common in CD than in ITB. Overall prevalence of EIMs in these patients is similar to that of the West.

Leukopenia predicts remission in patients with inflammatory bowel disease and Behcet's disease on thiopurine maintenance

BACKGROUNDS

The thiopurine drugs, azathioprine (AZA), and 6-mercaptopurine (6-MP) are well-established drugs for the treatment of inflammatory bowel disease (IBD). Although leukopenia is a well-recognized side effect of AZA/6-MP treatment, its association with therapeutic effects has yet to be determined. We therefore evaluated the influences of thiopurine-induced leukopenia on the long-term prognosis of IBD.

METHODS

We included 196 IBD patients [45 with ulcerative colitis (UC), 68 with Crohn's disease (CD), and 83 with intestinal Behçet's disease (BD)] who were treated with AZA/6-MP and achieved remission between January 2006 and December 2012. We retrospectively analyzed patient characteristics, AZA/6-MP maintenance dose (mg/kg), the lowest white blood cell (WBC) count during AZA/6-MP treatment, duration of remission, and the occurrence of relapse. We compared the clinical variables between leukopenic (n = 120, WBC count <4,000/μL) and nonleukopenic (n = 76, WBC count ≥ 4,000/μL) patients.

RESULTS

The two groups were well matched for baseline clinical characteristics. The cumulative relapse-free survival rate was higher in the leukopenic group than the nonleukopenic group by Kaplan-Meier survival analysis (log-rank test, P < 0.001). On multivariate analysis, age, duration of AZA/6-MP treatment, presence of macrocytosis, and the presence of leukopenia were negatively associated with relapse (odds ratios 0.975, 0.988, 0.563, and 0.390, respectively). On subgroup analysis, the cumulative relapse-free survival rate was significantly higher in the leukopenic group than in the nonleukopenic group for all types of IBDs, including UC, CD, and intestinal BD (log-rank test, P = 0.032, 0.047, and 0.002, respectively).

CONCLUSION

Leukopenia during thiopurine maintenance therapy was associated with prolonged remission in patients with IBD and Behcet's disease.

Immunochip analysis identification of 6 additional susceptibility loci for Crohn's disease in Koreans

BACKGROUND

Crohn's disease (CD) is an intractable inflammatory bowel disease of unknown cause. Recent genome-wide association studies of CD in Korean and Japanese populations suggested marginal sharing of susceptibility loci between Caucasian and Asian populations. As the 7 identified loci altogether explain 5.31% of the risk for CD, the objective of this study was to identify additional CD susceptibility loci in the Korean population.

METHODS

Using the ImmunoChip custom single-nucleotide polymorphism array designed for dense genotyping of 186 loci identified through GWAS, we analyzed 722 individuals with CD and 461 controls for 96,048 SNP markers in the discovery stage, followed by validation in an additional 948 affected individuals and 977 controls.

RESULTS

We confirmed 6 previously reported loci in Caucasian: GPR35 at 2q37 (rs3749172; P = 5.30 × 10, odds ratio [OR] = 1.45), ZNF365 at 10q21 (rs224143; P = 2.20 × 10, OR = 1.38), ZMIZ1 at 10q22 (rs1250569; P = 3.05 × 10, OR = 1.30), NKX2-3 at 10q24 (rs4409764; P = 7.93 × 10, OR = 1.32), PTPN2 at 18p11 (rs514000; P = 9.00 × 10, OR = 1.33), and USP25 at 21q11 (rs2823256; P = 2.49 × 10, OR = 1.35), bringing the number of known CD loci (including 3 in the HLA) in Koreans to 15. The 6 additional loci increased the total genetic variance for CD risk from 5.31% to 7.27% in Koreans.

CONCLUSIONS

Although the different genetic backgrounds of CD between Asian and Western countries has been well established for the major susceptibility genes, our findings of overlapping associations offer new insights into the genetic architecture of CD.

Long-term clinical outcomes of korean patient with Crohn's disease following early use of infliximab

Background/Aims

Several recent studies have reported that the early use of infliximab (IFX) improves the prognosis of Crohn's disease (CD). However, no data are available from Asian populations, as the forementioned studies have all been conducted in Western countries. The aim of the current study was to evaluate the impact of early use of IFX on the prognosis of Korean patients with CD.

Methods

Patients with a diagnosis of CD established between July 1987 and January 2012 were investigated in 12 university hospitals in Korea. Because insurance coverage for IFX treatment began in August 2005, patients were assigned to either of 2 groups based on diagnosis date. The first group included patients diagnosed from July 1987 to December 2005, and the second from January 2006 to January 2012. We compared the cumulative probabilities of operation and reoperation between the two groups using the Kaplan-Meier method and a log-rank test.

Results

Of the 721 patients investigated, 443 (61.4%) comprized the second group. Although the cumulative probabilities of immunosuppressant (P<0.001) and IFX use (P<0.001) after diagnosis were significantly higher in the second group, there were no significant differences in cumulative probabilities of operation (P=0.905) or reoperation (P=0.418) between two groups.

Conclusions

The early use of IFX did not reduce CD-related surgery requirements in Korean patients with CD. These study results suggest that the early use of IFX may have little impact on the clinical outcome of CD in Korean patients in the setting of a conventional step-up algorithm.

Does carotid intima-media thickness increase in patients with inflammatory bowel disease?

Background/Aims

Mesenteric microvascular thrombosis has been implicated as a contributing factor to the pathogenesis of inflammatory bowel disease (IBD). The aim of the current study was to assess the possibility of subclinical atherosclerosis in patients with IBD by measuring their carotid intima-media thickness (c-IMT).

Methods

Thirty-eight patients with IBD who were followed-up for at least 3 years participated. Patients with a history of cardiovascular disease and known risk factors for atherosclerosis were excluded. As a control group, 38 healthy patients matched for age and gender without atherosclerosis risk factors were included. Carotid ultrasonography was performed in all patients and controls. Patient baseline characteristics and laboratory parameters were recorded to evaluate atherosclerosis risk factors.

Results

The mean age of patients with IBD was 38.5±6.62 years. Twenty-three patients with IBD were diagnosed with ulcerative colitis and the other 15 cases were diagnosed with Crohn's disease. The median duration of disease was 52.0 months. Serologic markers such as erythrocyte sedimentation rate, C-reactive protein (CRP), and cholesterol levels differed significantly, however, there was no significant difference in c-IMT between patients with IBD and those in the control group (0.53±0.10 mm vs. 0.53±0.07; P=0.85). Multivariate analysis revealed that body mass index, CRP, disease duration, and age were significantly correlated with c-IMT in patients with IBD.

Conclusions

The results of the current study did not show an increase in c-IMT in patients with IBD. Further studies that include more subjects and a longer follow-up period will be necessary in order to evaluate the risk of atherosclerosis in Korean patients with IBD.

Modulation of Colitis-associated Colon Tumorigenesis by Baicalein and Betaine

In this review, we will summarize the current understanding of modulation of colitis-associated colon tumorigenesis by two natural products, baicalein and betaine, which have anti-inflammatory activities. Baicalein and betaine have been shown to provide various health benefits to organism in many ways. Baicalein is a phenolic flavonoid derived originally from the root of Scutellaria baicalensis Georgi. From ancient times, baicalein has widely been used in oriental medicines as an anti-inflammatory and anti-cancer therapy. Betaine, trimethylglycine, is an essential biochemical molecule of the methionine/homocysteine cycle and is synthesized by conversion of choline. Betaine is an important human nutrient obtained from various foods including sugar beet and lycium. Betaine has provided various health benefits including disease prevention. However, the action mechanisms of their activity remain poorly understood. Recent studies reported the effects of baicalein and betaine on cytotoxicity against colon cancer cells and chemically induced colitis-associated colon tumorigenesis in mice. Administrations of baicalein and betaine containing diets significantly inhibited the incidence of tumors and hyperplasia with down-regulation of inflammation. Therefore, baicalein and betaine might be applicable to the prevention of inflammation-associated colon carcinogenesis.

Effect of follow-up endoscopy on the outcomes of patients with inflammatory bowel disease

BACKGROUND

Little is known about the role of follow-up endoscopy in patients with inflammatory bowel disease (IBD).

AIM

The present study aimed to evaluate whether repeated endoscopies would be beneficial in improving outcomes of patients with IBD.

METHODS

Patients who had been initially confirmed to have IBD at two tertiary hospitals in Korea were regularly followed and included in this study. The clinical impact as assessed by the presence or absence of a change in management after endoscopy and cumulative hospitalization rate was compared between two groups classified according to the presence or absence of indications.

RESULTS

A total of 188 patients with IBD were enrolled [69 patients with Crohn's disease (CD) and 119 with ulcerative colitis (UC)]. Of these patients, 130 underwent follow-up endoscopy (48 with CD and 82 with UC). The rate of management change was significantly higher in the group with indications for follow-up endoscopy (p = 0.001 in CD and <0.001 in UC). The presence of any indications for follow-up endoscopy was found to be a significant predictor of hospitalization risk in patients with UC (p = 0.015), but not in those with CD. However, there was no significant difference in cumulative hospitalization hazard with respect to treatment change in patients without any endoscopic indications (p = 0.561 in CD and 0.423 in UC).

CONCLUSIONS

Follow-up endoscopy might not have a significant impact on the overall clinical course and outcomes in patients with IBD. However, the presence of endoscopic indications predicts a poor clinical outcome in UC.

Crohn's disease in Korea: past, present, and future

The epidemiology, genetics, and clinical manifestations of Crohn's disease (CD) vary considerably among geographic areas and ethnic groups. Thus, identifying the characteristics of Korean CD is important for establishing management strategies appropriate for Korean patients. Since the mid-2000s, many studies have investigated the characteristic features of Korean CD. The incidence and prevalence rates of CD have been increasing rapidly in Korea, especially among the younger population. Unlike Western data, Korean CD shows a male predominance and a lower proportion of isolated colonic disease. Perianal lesions are more prevalent than in Western countries. Genome-wide association studies have confirmed that genetic variants in TNFSF15, IL-23R, and IRGM, but not ATG16L1, are associated with CD susceptibility in the Korean population. Studies of the associations between genetic mutations and the clinical course of CD are underway. Although it has been generally accepted that the clinical course of Korean CD is milder than that in Western countries, recent studies have shown a comparable rate of intestinal resection in Korean and Western CD patients. An ongoing nationwide, hospital-based cohort study is anticipated to provide valuable information on the natural history and prognosis of Korean CD in the near future.

Efficacy of early immunomodulator therapy on the outcomes of Crohn's disease

BACKGROUND

The natural course of Crohn's disease (CD), with continuing relapses and remissions, leads to irreversible intestinal damage. Early adoption of immunomodulator therapy has been proposed in order to address this; however, it is still uncertain whether early immunomodulator therapy could affect the natural course of the disease in real practice. We evaluated the efficacy of such therapy on the prognosis of newly diagnosed patients with CD.

METHODS

This retrospective study included 168 patients who were newly diagnosed with CD and who started treatment at Severance Hospital, Seoul, Korea between January 2006 and March 2013. The short- and long-term outcomes were compared between patients treated with early immunomodulator therapy and those treated with conventional therapy.

RESULTS

A Kaplan-Meier analysis identified that administration of immunomodulators within 6 months after diagnosis of CD was superior to conventional therapy in terms of clinical remission and corticosteroid-free remission rates (P=0.043 and P=0.035). However, P=0.827). Patients with a baseline elevated CRP level were more likely to relapse (P<0.005). Drug-related adverse events were more frequent in the early immunomodulator therapy group than in the conventional therapy group P=0.029).

CONCLUSIONS

Early immunomodulator therapy was more effective than conventional therapy in inducing remission, but not in preventing relapse. Baseline high CRP level was a significant indicator of relapse.