CORE-IBD: A Multidisciplinary International Consensus Initiative to Develop a Core Outcome Set for Randomized Controlled Trials in Inflammatory Bowel Disease.

BACKGROUND & AIMS: End points to determine the efficacy and safety of medical therapies for Crohn's disease (CD) and ulcerative colitis (UC) are evolving. Given the heterogeneity in current outcome measures, harmonizing end points in a core outcome set for randomized controlled trials is a priority for drug development in inflammatory bowel disease. METHODS: Candidate outcome domains and outcome measures were generated from systematic literature reviews and patient engagement surveys and interviews. An iterative Delphi process was conducted to establish consensus: panelists anonymously voted on items using a 9-point Likert scale, and feedback was incorporated between rounds to refine statements. Consensus meetings were held to ratify the outcome domains and core outcome measures. Stakeholders were recruited internationally, and included gastroenterologists, colorectal surgeons, methodologists, and clinical trialists. RESULTS: A total of 235 patients and 53 experts participated. Patient-reported outcomes, quality of life, endoscopy, biomarkers, and safety were considered core domains; histopathology was an additional domain for UC. In CD, there was consensus to use the 2-item patient-reported outcome (ie, abdominal pain and stool frequency), Crohn's Disease Activity Index, Simple Endoscopic Score for Crohn's Disease, C-reactive protein, fecal calprotectin, and co-primary end points of symptomatic remission and endoscopic response. In UC, there was consensus to use the 9-point Mayo Clinic Score, fecal urgency, Robarts Histopathology Index or Geboes Score, fecal calprotectin, and a composite primary end point including both symptomatic and endoscopic remission. Safety outcomes should be reported using the Medical Dictionary for Regulatory Activities. CONCLUSIONS: This multidisciplinary collaboration involving patients and clinical experts has produced the first core outcome set that can be applied to randomized controlled trials of CD and UC.

Global Hospitalization Trends for Crohn's Disease and Ulcerative Colitis in the 21st Century: A Systematic Review With Temporal Analyses.

BACKGROUND & AIMS: The evolving epidemiologic patterns of inflammatory bowel disease (IBD) throughout the world, in conjunction with advances in therapeutic treatments, may influence hospitalization rates of IBD. We performed a systematic review with temporal analysis of hospitalization rates for IBD across the world in the 21st century. METHODS: We systematically reviewed Medline and Embase for population-based studies reporting hospitalization rates for IBD, Crohn's disease (CD), or ulcerative colitis (UC) in the 21st century. Log-linear models were used to calculate the average annual percentage change (AAPC) with associated 95% confidence intervals (95% CIs). Random-effects meta-analysis pooled country-level AAPCs. Data were stratified by the epidemiologic stage of a region: compounding prevalence (stage 3) in North America, Western Europe, and Oceania vs acceleration of incidence (stage 2) in Asia, Eastern Europe, and Latin America vs emergence (stage 1) in developing countries. RESULTS: Hospitalization rates for a primary diagnosis of IBD were stable in countries in stage 3 (AAPC, -0.13%; 95% CI, -0.72 to 0.97), CD (AAPC, 0.20%; 95% CI, -1.78 to 2.17), and UC (AAPC, 0.02%; 95% CI, -0.91 to 0.94). In contrast, hospitalization rates for a primary diagnosis were increasing in countries in stage 2 for IBD (AAPC, 4.44%; 95% CI, 2.75 to 6.14), CD (AAPC, 8.34%; 95% CI, 4.38 to 12.29), and UC (AAPC, 3.90; 95% CI, 1.29 to 6.52). No population-based studies were available for developing regions in stage 1 (emergence). CONCLUSIONS: Hospitalization rates for IBD are stabilizing in countries in stage 3, whereas newly industrialized countries in stage 2 have rapidly increasing hospitalization rates, contributing to an increasing burden on global health care systems.

Development of the global inflammatory bowel disease visualization of epidemiology studies in the 21st century (GIVES-21).

BACKGROUND: There is a rapid increase in the incidence of inflammatory bowel diseases (IBD) in newly industrialized countries, yet epidemiological data is incomplete. We herein report the methodology adopted to study the incidence of IBD in newly industrialized countries and to evaluate the effect of environmental factors including diet on IBD development. METHODS: Global IBD Visualization of Epidemiology Studies in the 21st Century (GIVES-21) is a population-based cohort of newly diagnosed persons with Crohn's disease and ulcerative colitis in Asia, Africa, and Latin America to be followed prospectively for 12 months. New cases were ascertained from multiple sources and were entered into a secured online system. Cases were confirmed using standard diagnostic criteria. In addition, endoscopy, pathology and pharmacy records from each local site were searched to ensure completeness of case capture. Validated environmental and dietary questionnaires were used to determine exposure in incident cases prior to diagnosis. RESULTS: Through November 2022, 106 hospitals from 24 regions (16 Asia; 6 Latin America; 2 Africa) have joined the GIVES-21 Consortium. To date, over 290 incident cases have been reported. All patients have demographic data, clinical disease characteristics, and disease course data including healthcare utilization, medication history and environmental and dietary exposures data collected. We have established a comprehensive platform and infrastructure required to examine disease incidence, risk factors and disease course of IBD in the real-world setting. CONCLUSIONS: The GIVES-21 consortium offers a unique opportunity to investigate the epidemiology of IBD and explores new clinical research questions on the association between environmental and dietary factors and IBD development in newly industrialized countries.

Descriptive Epidemiology of Pediatric Inflammatory Bowel Disease in Oceania: A Systematic Review and Meta-Analysis.

OBJECTIVES: Pediatric inflammatory bowel diseases (IBDs) are chronic, idiopathic illnesses of the digestive tract, which can impact adversely on children's quality of life and burden health systems. International studies have shown these diseases are increasing. The aim was to describe pediatric IBD epidemiology across Oceania by conducting a systematic review and meta-analysis of incidence and prevalence. METHODS: Medline, EMBASE and Web of Science databases were searched in October 2022 for studies reporting rates of IBD, Crohn disease (CD), or ulcerative colitis (UC) in children (≤19 years). Several data collection methodologies were included and pooled estimates of incidence and prevalence were calculated using a random effects model with I2 measures of heterogeneity. RESULTS: Nineteen articles provided 15 incidence and 7 prevalence studies. Fourteen studies were from Australia, 8 studies from New Zealand, and no studies were found from the Pacific Islands. Study dates ranged from 1950 to 2020 with 11 studies using population-based designs. Pooled estimates for annual incidence were IBD 4.1 (3.4-4.8, I2 = 98.7), CD 2.3 (1.9-2.7, I2 = 98.6), and UC 0.9 (0.6-1.1, I2 = 96.8) per 100,000 person-years. Prevalence rates were IBD 36.0 (23.5-48.5, I2 = 98.4), CD 23.2 (6.6-39.8, I2 = 97.8), and UC 7.6 (2.7-12.5, I2 = 99.6) per 100,000 persons. CONCLUSIONS: Pediatric IBD is prevalent in Oceania with high incidence rates, particularly for CD. Low rates of IBD were observed in indigenous Australian, Maori, and New Zealand Pacific children and there were no studies from the Pacific Islands highlighting this as an area in need of further research.

Exploring the Relationship Between Self-Isolation and Distress Among People with Gastrointestinal Disorders During the COVID-19 Pandemic.

This study aimed to explore the association between perceived isolation and symptoms of distress in people with GI disorders at the time of the pandemic; and to examine factors which moderate this relationship. This online cross-sectional survey was advertised in May-September 2020 via patient organisations and associated social media. Overall, 831 people (82% female, mean age 49 years) from 27 countries participated. A significant relationship between social isolation and psychological distress was noted (r = .525, p < .001). GI symptoms moderated the association between isolation and distress (B = .047, t = 2.47, p = .015). Interventions targeting these factors may help to reduce distress in people with GI disorders at the time of major stressors such as the COVID-19 pandemic.

Effect of IBD medications on COVID-19 outcomes: results from an international registry.

OBJECTIVE: We sought to evaluate COVID-19 clinical course in patients with IBD treated with different medication classes and combinations. DESIGN: Surveillance Epidemiology of Coronavirus Under Research Exclusion for Inflammatory Bowel Disease (SECURE-IBD) is a large, international registry created to monitor outcomes of IBD patients with confirmed COVID-19. We used multivariable regression with a generalised estimating equation accounting for country as a random effect to analyse the association of different medication classes with severe COVID-19, defined as intensive care unit admission, ventilator use and/or death. RESULTS: 1439 cases from 47 countries were included (mean age 44.1 years, 51.4% men) of whom 112 patients (7.8%) had severe COVID-19. Compared with tumour necrosis factor (TNF) antagonist monotherapy, thiopurine monotherapy (adjusted OR (aOR) 4.08, 95% CI 1.73 to 9.61) and combination therapy with TNF antagonist and thiopurine (aOR 4.01, 95% CI 1.65 to 9.78) were associated with an increased risk of severe COVID-19. Any mesalamine/sulfasalazine compared with no mesalamine/sulfasalazine use was associated with an increased risk (aOR 1.70, 95% CI 1.26 to 2.29). This risk estimate increased when using TNF antagonist monotherapy as a reference group (aOR 3.52, 95% CI 1.93 to 6.45). Interleukin-12/23 and integrin antagonists were not associated with significantly different risk than TNF antagonist monotherapy (aOR 0.98, 95% CI 0.12 to 8.06 and aOR 2.42, 95% CI 0.59 to 9.96, respectively). CONCLUSION: Combination therapy and thiopurines may be associated with an increased risk of severe COVID-19. No significant differences were observed when comparing classes of biologicals. These findings warrant confirmation in large population-based cohorts.MKH should be changed to MDK for co-last author line.

Corticosteroids, But Not TNF Antagonists, Are Associated With Adverse COVID-19 Outcomes in Patients With Inflammatory Bowel Diseases: Results From an International Registry.

BACKGROUND AND AIMS: The impact of Coronavirus disease 2019 (COVID-19) on patients with inflammatory bowel disease (IBD) is unknown. We sought to characterize the clinical course of COVID-19 among patients with IBD and evaluate the association among demographics, clinical characteristics, and immunosuppressant treatments on COVID-19 outcomes. METHODS: Surveillance Epidemiology of Coronavirus Under Research Exclusion for Inflammatory Bowel Disease (SECURE-IBD) is a large, international registry created to monitor outcomes of patients with IBD with confirmed COVID-19. We calculated age-standardized mortality ratios and used multivariable logistic regression to identify factors associated with severe COVID-19, defined as intensive care unit admission, ventilator use, and/or death. RESULTS: 525 cases from 33 countries were reported (median age 43 years, 53% men). Thirty-seven patients (7%) had severe COVID-19, 161 (31%) were hospitalized, and 16 patients died (3% case fatality rate). Standardized mortality ratios for patients with IBD were 1.8 (95% confidence interval [CI], 0.9-2.6), 1.5 (95% CI, 0.7-2.2), and 1.7 (95% CI, 0.9-2.5) relative to data from China, Italy, and the United States, respectively. Risk factors for severe COVID-19 among patients with IBD included increasing age (adjusted odds ratio [aOR], 1.04; 95% CI, 1.01-1.02), ≥2 comorbidities (aOR, 2.9; 95% CI, 1.1-7.8), systemic corticosteroids (aOR, 6.9; 95% CI, 2.3-20.5), and sulfasalazine or 5-aminosalicylate use (aOR, 3.1; 95% CI, 1.3-7.7). Tumor necrosis factor antagonist treatment was not associated with severe COVID-19 (aOR, 0.9; 95% CI, 0.4-2.2). CONCLUSIONS: Increasing age, comorbidities, and corticosteroids are associated with severe COVID-19 among patients with IBD, although a causal relationship cannot be definitively established. Notably, tumor necrosis factor antagonists do not appear to be associated with severe COVID-19.

Development and Validation of a Self-management Skills Assessment Tool for Children With Inflammatory Bowel Disease: The Inflammatory Bowel Disease-Skills Tasks and Abilities Record (IBD-STAR).

OBJECTIVES: For children with inflammatory bowel disease (IBD), the development of self-management skills has the potential to improve disease outcomes. No assessment tools are aimed at measuring self-management skills in this population. A tool was developed called the IBD-Skills Tasks and Abilities Record (IBD-STAR) which measures children's allocation of responsibility for specific skills. IBD-STAR contains 18 items, scored whether completed independently (score 2), with help (score 1) or not at all (score 0). METHODS: Children with IBD completed IBD-STAR; one parent and a gastroenterologist completed a series of visual analogue scales that corresponded with each IBD-STAR section. Children's IBD-STAR scores were examined against independent variables and compared with the parent and clinician visual analogue scale scores. Reliability was calculated using Cronbach's alpha. RESULTS: Twenty-five Cronbach's alpha with IBD participated, mean age 14 years (standard deviation (SD) 1.7), 14 (56%) were boys, and 21 (84%) had Crohn's disease. The mean IBD-STAR score was 27.1 (SD 5.7), equivalent to a score of 75%. Age was the only independent variable significantly associated with scores (P = 0.017). Parents consistently underestimated their children in all sections, but clinician assessments were more closely aligned. Reliability for IBD-STAR was good with an overall Cronbach's alpha of 0.84. CONCLUSION: IBD-STAR reports the allocation of responsibility for self-management skills with good agreement between children and clinician, and with comprehensible differences with their parents. Such a tool may be used to identify children with IBD in need of support or to measure the efficacy of targeted interventions.

Level of UV Exposure, Skin Type, and Age Are More Important than Thiopurine Use for Keratinocyte Carcinoma Development in IBD Patients.

BACKGROUND: Retrospective studies observe an increased risk of keratinocyte carcinomas (KCs) in patients with inflammatory bowel disease (IBD) on thiopurine (TP) medication. The role of traditional risk factors such as skin type and sun protection behavior has not been studied in this population. This study aimed to examine traditional KC risk factors and thiopurine use on skin cancer development in an IBD cohort. METHODS: Consecutive IBD patients were recruited from four specialist centers in Australia and New Zealand, each with varying UV exposure indices. Data pertaining to race, skin color, freckling and sun protection behavior, dose of TP therapy, and skin cancer development were elicited through a self-reported questionnaire. RESULTS: A total of 691 IBD patients were included with 62 reporting KC development. Thiopurine usage was similar among patients who developed skin cancer compared with those who did not (92% vs. 89%, p = 0.3). There was no statistically significant association between KC development and TP dose or 6-thioguanine nucleotide levels. In multivariate modeling, four factors were independently and significantly associated with KC: age over 61 years old versus less than 30 years old (OR 6.76; 95% CI 2.38-19.18), residing in Brisbane versus Christchurch (OR 3.3; 95% CI 1.6-6.8), never staying in the shade versus staying in the shade ≥ 50% of the time (OR 3.8; 95% CI 1.4-10.5), and having a skin type that never tanned versus other skin types (OR 6.9; 95% CI 2.9-16.0). CONCLUSION: Skin type, age, and sun protection behavior are more important risk factors for KC development than thiopurine medication use in this IBD population.

Response pattern analysis of IBD-KID: A knowledge assessment tool for children with inflammatory bowel disease.

AIM: Paediatric inflammatory bowel disease (IBD) is a chronic relapsing condition requiring adherence to complex treatment regimens to achieve best outcomes. Adherence is frequently low in this population but can be improved by increasing disease- and treatment-related knowledge. The IBD-knowledge inventory device (IBD-KID) is a knowledge assessment tool specifically developed and validated for children with IBD. To analyse IBD-KID participant response patterns in order to review the strength of the tool. METHODS: A cohort of children with IBD completed IBD-KID, and their responses were used to assess the tool's validity and feasibility. Item response analysis assessed the item difficulty and the ability of items to discriminate between high/low scorers. The analysis considered item structure, readability and the effectiveness of multiple choice items. RESULTS: A total of 105 completed IBD-KID assessments showed that 12 items (52%) had an acceptable difficulty level, and 17 (74%) were effective at discriminating between high/low scorers. Nine (61%) had good readability, but comprehension levels ranged from 5 to 18 years. Seven (30%) had elevated 'don't know' responses, highlighting the need for content and construction review. Of the 10 multiple choice items, 9 were complex and not functioning efficiently. Internal consistency was acceptable but could be improved by removing two items. CONCLUSIONS: The response analysis metrics were reviewed by an expert panel and provided a framework for IBD-KID improvements with the aim of increasing discrimination and reducing difficulty without adversely affecting reliability. The proposed revisions will address components that may have caused children to answer incorrectly due to confusion rather than lack of knowledge.

Central Sensitization Inventory Mediates the Relationship Between Inflammatory Bowel Disease Activity and Worse Musculoskeletal Pain Experiences.

BACKGROUND: Musculoskeletal conditions are well documented in inflammatory bowel disease (IBD). However, whether IBD activity influences musculoskeletal pain experiences is uncertain. Central sensitization has been proposed in patients with IBD who are suffering from persistent pain. Identification of central sensitization symptomology using the Central Sensitization Inventory (CSI) has been reported in many pain-related disorders. Aims of this study were to explore predictive relationships between IBD activity and musculoskeletal pain experiences (severity/interference), and the mediating effects of the CSI. METHODS: A cross-sectional online survey was performed exploring self-reported musculoskeletal pain in adults with IBD. Survey questionnaires included IBD activity indices, numeric rating scales, PROMIS Pain Interference, and the CSI. Linear regression was used to examine the relationship between active IBD and pain experiences. Simple and serial mediation analyses were used to explore mediation models: independent variable (IBD activity), dependent variables (severity/interference), and mediators (CSI/severity). RESULTS: 208 adults with IBD, 18 to 88 years of age, reported musculoskeletal pain. Regression analysis identified IBD activity as a significant predictor of worse pain severity (R2  = 0.039, P < 0.005) and interference (R2  = 0.067, P < 0.001). Simple mediation showed a significant indirect effect from CSI scores between IBD activity and pain severity. Serial mediation analysis showed a significant indirect effect from CSI scores and pain severity, between IBD activity and pain interference. CONCLUSION: Active IBD demonstrated a positive association with worse musculoskeletal pain experiences. The CSI demonstrated significant mediation between active IBD and pain severity. Additionally, the CSI and pain severity demonstrated significant mediation between active IBD and pain interference. This suggests that symptoms of central sensitization significantly influence musculoskeletal pain experiences in IBD.

A Symptom Self-report Tool for Children With Inflammatory Bowel Disease (IBDnow).

OBJECTIVES: Clinical symptom evaluation for children with inflammatory bowel disease (IBD) is typically done using composite tools: the Pediatric Crohn's Disease Activity Index (PCDAI) and Pediatric Ulcerative Colitis Activity Index (PUCAI). Both rely on clinician interpretation of child or parent symptom recall. No universal self-report tool has yet been developed for children with IBD to assess and report their symptoms. The research objective was to develop a self-report tool that produced information congruent with that obtained by clinicians using the PUCAI or PCDAI. METHODS: A children's symptom self-report tool (IBDnow) was developed with picture and text Likert symptom scales. The clinician and child completed their reports during the same outpatient consultation. Agreement levels were calculated at the individual level (identical child and clinician answers), category level (symptom severity), and aggregate level (cohort scores). Internal consistency was measured with Cronbach alpha. RESULTS: One hundred children from Christchurch (New Zealand) (n = 65), and Sydney (Australia) (n = 35) completed the study (Crohn's Disease (CD):88, ulcerative colitis (UC):12), mean age 13.9 years (±3.6). Mean individual agreement was 0.76 (±0.19). Category severity had very good or good inter-rater reliability for 5 of the 7 symptom scales and overall severity agreement of 76%. Aggregate mean scores were significantly different between clinicians (14.9, ±18.8), and participants (21.6, ±19.4), (P <0.005, confidence interval -9.0, -4.4), but 60 pairs had scores within a 10% margin. Cronbach alpha was 0.74. CONCLUSIONS: This self-report tool had good proportionate agreement between raters, and good crude agreement for symptom categories. Assigning PUCAI or PCDAI scores caused inter-rater discrepancies to be misleadingly magnified. Pediatric gastroenterologists may consider utilizing IBDnow to elicit symptom self-reports from children with IBD to enable them to communicate meaningful information on their ongoing symptom burden. This would be a positive step in helping children feel included in clinical encounters and promoting self-management, at the same time producing valid, subjective symptom recall.

Validation of the inflammatory bowel disease disability index for self-report and development of an item-reduced version.

BACKGROUND AND AIM: The Inflammatory Bowel Disease Disability Index (IBD-DI) is a measure of disability in inflammatory bowel disease (IBD). The IBD-DI is validated for use as a clinical interview but not for use as a self-report questionnaire. We aimed to validate the IBD-DI for self-report (IBD-DI-SR) and to reduce the number of items, using IBD patients from two centers. METHODS: Between April and August 2017, ambulatory IBD patients were recruited from Christchurch Hospital, New Zealand and Concord Hospital, Australia. The IBD-DI clinical interview version was compared with a self-report version. Participants were randomized to do the clinical interview or self-report first. Validation of the IBD-DI-SR involved calculating the correlation coefficient between the clinician completed and self-reported version of the IBD-DI and Cronbach's α of internal consistency of the IBD-DI-SR. To create an item-reduced version, multiple linear regression was used. The R2 of the model described the overall association between the item-reduced IBD-DI-SR and the IBD-DI. RESULTS: One hundred fourteen patients (57 from Christchurch and 57 from Sydney) completed the IBD-DI-SR validation phase, of whom 63 had Crohn's disease and 51 had ulcerative colitis. The Pearson correlation coefficient between the IBD-DI-SR and IBD-DI is 0.90 (P < 0.001), and Cronbach's α of the IBD-DI-SR was 0.86. The item-reduced version of the IBD-DI-SR consisted of eight questions instead of 28, explaining 77% of the variance. CONCLUSIONS: The IBD-DI-SR has demonstrated reliability and validity. The item-reduced IBD-DI-SR is a concise self-report instrument for measuring IBD disability, which makes the IBD-DI more widely usable.

Rising Incidence of Paediatric Inflammatory Bowel Disease in Canterbury, New Zealand, 1996-2015.

BACKGROUND: The incidence of paediatric inflammatory bowel disease (IBD) around the world is increasing. Canterbury, New Zealand, has one of the highest Crohn disease (CD) incidence rates published. The present study aimed to document the incidence of paediatric IBD in Canterbury between 1996 and 2015. METHODS: All patients diagnosed with IBD in Canterbury, while younger than 16 years, between January 1, 1996 and December 31, 2015 were identified. Demographic and disease phenotypic details were collected and entered into a secure database. Age-specific population data for Canterbury were obtained and annual incidence rates were then calculated. RESULTS: The mean annual incidence rate over the 20-year period was 7.18/100,000 (95% confidence interval 5.55-8.81) children. There was a 4-fold increase in the incidence of paediatric IBD in Canterbury between 1996 and 2015. The ratio of CD to ulcerative colitis (UC) diagnosed was 8.4:1. Disease phenotype of CD and UC, based on the Paris classification, were comparable with other studies. CONCLUSIONS: The incidence of paediatric IBD in Canterbury has increased dramatically during the last 2 decades. Some of the observed incidence rates are among the highest documented anywhere in the world. The preponderance of CD over UC in the present study is the highest published.

Prospective Incidence of Paediatric Inflammatory Bowel Disease in New Zealand in 2015: Results From the Paediatric Inflammatory Bowel Disease in New Zealand (PINZ) Study.

BACKGROUND: The global incidence of paediatric inflammatory bowel disease (IBD) is increasing. Much of the evidence attesting to this has arisen from North America and Europe. There is a relative paucity of information on the epidemiology of paediatric IBD in the Southern Hemisphere. The present study aimed to document the prospectively collected incidence of paediatric IBD in New Zealand in 2015. METHODS: All patients younger than 16 years of age and diagnosed with IBD in New Zealand between 1 January 2015 and 31 December 2015 were identified. Demographic and disease phenotypic details were collected and entered into a secure database. Age-specific population data for New Zealand were obtained and national incidence rates for IBD and its subtypes were calculated. RESULTS: The prospectively calculated incidence of paediatric IBD, Crohn disease, ulcerative colitis (UC), and IBD unclassified in New Zealand in 2015 were 5.2 (95% confidence interval 3.9-6.8), 3.5 (2.4-4.8), 1.0 (0.5-1.8), and 0.7 (0.3-1.4) per 100,000 children, respectively. CONCLUSIONS: Incidence rates of paediatric IBD in New Zealand are comparable to the highest rates published in the literature from Western Europe and North America. Ongoing prospective ascertainment of the incidence of paediatric IBD is required to better understand the environmental factors, which are accounting for this increase in disease burden.

Inherited determinants of Crohn's disease and ulcerative colitis phenotypes: a genetic association study.

BACKGROUND: Crohn's disease and ulcerative colitis are the two major forms of inflammatory bowel disease; treatment strategies have historically been determined by this binary categorisation. Genetic studies have identified 163 susceptibility loci for inflammatory bowel disease, mostly shared between Crohn's disease and ulcerative colitis. We undertook the largest genotype association study, to date, in widely used clinical subphenotypes of inflammatory bowel disease with the goal of further understanding the biological relations between diseases. METHODS: This study included patients from 49 centres in 16 countries in Europe, North America, and Australasia. We applied the Montreal classification system of inflammatory bowel disease subphenotypes to 34,819 patients (19,713 with Crohn's disease, 14,683 with ulcerative colitis) genotyped on the Immunochip array. We tested for genotype-phenotype associations across 156,154 genetic variants. We generated genetic risk scores by combining information from all known inflammatory bowel disease associations to summarise the total load of genetic risk for a particular phenotype. We used these risk scores to test the hypothesis that colonic Crohn's disease, ileal Crohn's disease, and ulcerative colitis are all genetically distinct from each other, and to attempt to identify patients with a mismatch between clinical diagnosis and genetic risk profile. FINDINGS: After quality control, the primary analysis included 29,838 patients (16,902 with Crohn's disease, 12,597 with ulcerative colitis). Three loci (NOD2, MHC, and MST1 3p21) were associated with subphenotypes of inflammatory bowel disease, mainly disease location (essentially fixed over time; median follow-up of 10·5 years). Little or no genetic association with disease behaviour (which changed dramatically over time) remained after conditioning on disease location and age at onset. The genetic risk score representing all known risk alleles for inflammatory bowel disease showed strong association with disease subphenotype (p=1·65 × 10(-78)), even after exclusion of NOD2, MHC, and 3p21 (p=9·23 × 10(-18)). Predictive models based on the genetic risk score strongly distinguished colonic from ileal Crohn's disease. Our genetic risk score could also identify a small number of patients with discrepant genetic risk profiles who were significantly more likely to have a revised diagnosis after follow-up (p=6·8 × 10(-4)). INTERPRETATION: Our data support a continuum of disorders within inflammatory bowel disease, much better explained by three groups (ileal Crohn's disease, colonic Crohn's disease, and ulcerative colitis) than by Crohn's disease and ulcerative colitis as currently defined. Disease location is an intrinsic aspect of a patient's disease, in part genetically determined, and the major driver to changes in disease behaviour over time. FUNDING: International Inflammatory Bowel Disease Genetics Consortium members funding sources (see Acknowledgments for full list).

Concentrations of Adalimumab and Infliximab in Mothers and Newborns, and Effects on Infection.

BACKGROUND & AIMS: Little is known about in utero exposure to and postnatal clearance of anti-tumor necrosis factor (anti-TNF) agents in neonates. We investigated the concentrations of adalimumab and infliximab in umbilical cord blood of newborns and rates of clearance after birth, and how these correlated with drug concentrations in mothers at birth and risk of infection during the first year of life. METHODS: We performed a prospective study of 80 pregnant women with inflammatory bowel diseases at tertiary hospitals in Denmark, Australia, and New Zealand from March 2012 through November 2014: 36 received adalimumab and 44 received infliximab; 39 received concomitant thiopurines during pregnancy. Data were collected from medical records on disease activity and treatment before, during, and after pregnancy. Concentrations of anti-TNF agents were measured in blood samples from women at delivery and in umbilical cords, and in infants for every 3 months until the drug was no longer detected. RESULTS: The time from last exposure to anti-TNF agent during pregnancy correlated inversely with the concentration of the drugs in the umbilical cord (adalimumab: r = -0.64, P = .0003; infliximab: r = -0.77, P < .0001) and in mothers at time of birth (adalimumab, r = -0.80; infliximab, r = -0.80; P < .0001 for both). The median ratio of infant:mother drug concentration at birth was 1.21 for adalimumab (95% confidence interval [CI], 0.94-1.49) and 1.97 for infliximab (95% CI, 1.50-2.43). The mean time to drug clearance in infants was 4.0 months for adalimumab (95% CI, 2.9-5.0) and 7.3 months for infliximab (95% CI, 6.2-8.3; P < .0001). Drugs were not detected in infants after 12 months of age. Bacterial infections developed in 4 infants (5%) and viral infections developed in 16 (20%), all with benign courses. The relative risk for infection was 2.7 in infants whose mothers received the combination of an anti-TNF agent and thiopurine, compared with anti-TNF monotherapy (95% CI, 1.09-6.78; P = .02). CONCLUSIONS: In a prospective study of infants born to mothers who received anti-TNF agents during pregnancy, we detected the drugs until 12 months of age. There was an inverse correlation between the time from last exposure during pregnancy and drug concentration in the umbilical cord. Infliximab was cleared more slowly than adalimumab from the infants. The combination of an anti-TNF agent and thiopurine therapy during pregnancy increased the relative risk for infant infections almost 3-fold compared with anti-TNF monotherapy. Live vaccines therefore should be avoided for up to 1 year unless drug clearance is documented, and pregnant women should be educated on the risks of anti-TNF use.

Performance of risk prediction for inflammatory bowel disease based on genotyping platform and genomic risk score method.

BACKGROUND: Predicting risk of disease from genotypes is being increasingly proposed for a variety of diagnostic and prognostic purposes. Genome-wide association studies (GWAS) have identified a large number of genome-wide significant susceptibility loci for Crohn's disease (CD) and ulcerative colitis (UC), two subtypes of inflammatory bowel disease (IBD). Recent studies have demonstrated that including only loci that are significantly associated with disease in the prediction model has low predictive power and that power can substantially be improved using a polygenic approach. METHODS: We performed a comprehensive analysis of risk prediction models using large case-control cohorts genotyped for 909,763 GWAS SNPs or 123,437 SNPs on the custom designed Immunochip using four prediction methods (polygenic score, best linear genomic prediction, elastic-net regularization and a Bayesian mixture model). We used the area under the curve (AUC) to assess prediction performance for discovery populations with different sample sizes and number of SNPs within cross-validation. RESULTS: On average, the Bayesian mixture approach had the best prediction performance. Using cross-validation we found little differences in prediction performance between GWAS and Immunochip, despite the GWAS array providing a 10 times larger effective genome-wide coverage. The prediction performance using Immunochip is largely due to the power of the initial GWAS for its marker selection and its low cost that enabled larger sample sizes. The predictive ability of the genomic risk score based on Immunochip was replicated in external data, with AUC of 0.75 for CD and 0.70 for UC. CD patients with higher risk scores demonstrated clinical characteristics typically associated with a more severe disease course including ileal location and earlier age at diagnosis. CONCLUSIONS: Our analyses demonstrate that the power of genomic risk prediction for IBD is mainly due to strongly associated SNPs with considerable effect sizes. Additional SNPs that are only tagged by high-density GWAS arrays and low or rare-variants over-represented in the high-density region on the Immunochip contribute little to prediction accuracy. Although a quantitative assessment of IBD risk for an individual is not currently possible, we show sufficient power of genomic risk scores to stratify IBD risk among individuals at diagnosis.

Enhancements in Confidence, Acceptance, and Friendship at a Summer Camp for Children With Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD) affects many children and adolescents in terms of their confidence, acceptance, and ability to build friendships. New Zealand held its first summer camp for children with IBD in January 2015. We obtained feedback from the campers (ages 10-18 years) in terms of their confidence, acceptance, and quality of life. We also asked what experience was most beneficial to them, whether they made new friends with IBD, and if they would attend the camp again. Thirty-six campers responded (81.8% response rate; median age 14 years [range 10-18]; 83.3% Crohn disease; 41.7% girls). Most reported that the camp improved their confidence (86.1%), acceptance (83.3%), and overall quality of life (75.0%) relating to IBD. Moreover, most reported that meeting their fellow campers was the most beneficial experience to come from the camp (72.2%). Overall, these results emphasize the importance and relevance of such an undertaking.

Fecal biomarkers in inflammatory bowel disease.

Over the last two decades, knowledge on fecal biomarkers has substantially increased. Nowadays, these non-invasive markers of inflammation have significant clinical utility in the management of inflammatory bowel disease. Their use informs the decision to perform endoscopy before diagnosis is made right through to influencing therapeutic choices and the need for interval endoscopic assessment. In this review, the roles of two S100 proteins, calprotectin, and S100A12 are described along with that of lactoferrin, in the context of inflammatory bowel disease.