Interim Analysis of a Trial Evaluating the Utility of Non-Targeted Biopsies for Colorectal Neoplasia Detection in Inflammatory Bowel Disease.

Persons with inflammatory bowel disease (IBD) affecting the colorectum (cIBD) have a 1.5- to 2-fold higher risk of developing colorectal cancer (CRC) relative to age- and sex-matched members of the general population.1 Intensive surveillance colonoscopy is recommended in this population to detect and treat early neoplastic lesions before they evolve to incurable cancers.2 Some societies advocate for widespread non-targeted ("random") biopsies throughout the colorectum to screen for "invisible" neoplastic lesions, in addition to targeted biopsies and/or resection of visible lesions.2 Despite the theoretical value of non-targeted biopsies in this setting, there are no high-quality, controlled data to support this practice. In addition to adding significant time and costs to colonoscopy screening, extensive biopsy sampling may also increase the risk of colorectal bleeding and bowel perforation, particularly in elderly patients and those receiving anticoagulant/antiplatelet therapies. With the widespread adoption of disease-modifying biologic and small molecule therapies,3 mucosal healing as a treatment end point,4 high-definition endoscopes,5 and endoscopy quality standards,6 as well as reports of very low neoplasia yield for non-targeted biopsies (0.1%-0.2% of biopsies),7 many experts have started to question the value of non-targeted biopsies as an adjunct for neoplasia surveillance in persons with cIBD.8 However, a recent large French cohort study reported that non-targeted biopsies still identify up to 20% of all neoplastic foci in persons with cIBD,9 albeit primarily in individuals with other major CRC risk factors.

Dynamic Prediction of Advanced Colorectal Neoplasia in Inflammatory Bowel Disease.

BACKGROUND & AIMS: Colonoscopic surveillance is recommended in patients with colonic inflammatory bowel disease (IBD) given their increased risk of colorectal cancer (CRC). We aimed to develop and validate a dynamic prediction model for the occurrence of advanced colorectal neoplasia (aCRN, including high-grade dysplasia and CRC) in IBD. METHODS: We pooled data from 6 existing cohort studies from Canada, The Netherlands, the United Kingdom, and the United States. Patients with IBD and an indication for CRC surveillance were included if they underwent at least 1 follow-up procedure. Exclusion criteria included prior aCRN, prior colectomy, or an unclear indication for surveillance. Predictor variables were selected based on the literature. A dynamic prediction model was developed using a landmarking approach based on Cox proportional hazard modeling. Model performance was assessed with Harrell's concordance-statistic (discrimination) and by calibration curves. Generalizability across surveillance cohorts was evaluated by internal-external cross-validation. RESULTS: The surveillance cohorts comprised 3731 patients, enrolled and followed-up in the time period from 1973 to 2021, with a median follow-up period of 5.7 years (26,336 patient-years of follow-up evaluation); 146 individuals were diagnosed with aCRN. The model contained 8 predictors, with a cross-validation median concordance statistic of 0.74 and 0.75 for a 5- and 10-year prediction window, respectively. Calibration plots showed good calibration. Internal-external cross-validation results showed medium discrimination and reasonable to good calibration. CONCLUSIONS: The new prediction model showed good discrimination and calibration, however, generalizability results varied. Future research should focus on formal external validation and relate predicted aCRN risks to surveillance intervals before clinical application.

Environmental Factors Associated with Risk of Crohn's Disease Development in the Crohn's and Colitis Canada - Genetic, Environmental, Microbial Project.

BACKGROUND & AIMS: To date, it is unclear how environmental factors influence Crohn's disease (CD) risk and how they interact with biological processes. This study investigates the association between environmental exposures and CD risk and evaluates their association with pre-disease biomarkers. METHODS: We studied 4289 healthy first-degree relatives (FDRs) of patients with CD from the Crohn's and Colitis Canada - Genetic, Environmental, Microbial (CCC-GEM) project. Regression models identified environmental factors associated with future CD onset and their association with pre-disease biological factors, including altered intestinal permeability measured by urinary fractional excretion of lactulose to mannitol ratio (LMR); gut inflammation via fecal calprotectin (FCP) levels; and fecal microbiome composition through 16S rRNA sequencing. RESULTS: Over a 5.62-year median follow-up, 86 FDRs developed CD. Living with a dog between ages 5 and 15 (hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.40-0.96; P = .034), and living with a large family size in the first year of life (HR, 0.43; 95% CI, 0.21-0.85; P = .016) were associated with decreased CD risk, whereas having a bird at the time of recruitment (HR, 2.78; 95% CI, 1.36-5.68; P = .005) was associated with an increased CD risk. Furthermore, living with a dog was associated with reduced LMR, altered relative abundance of multiple bacterial genera, and increased Chao1 diversity, whereas bird owners had higher FCP levels. Large family during participants' first year of life was associated with altered microbiota composition without affecting FCP or LMR. CONCLUSION: This study identifies environmental variables associated with CD risk. These variables were also associated with altered barrier function, subclinical inflammation, and gut microbiome composition shifts, suggesting potential roles in CD pathogenesis.

Ultra-Processed Food, Disease Activity, and Inflammation in Ulcerative Colitis: The Manitoba Living With IBD Study.

INTRODUCTION: The purpose of this study was to investigate the relationship between ultra-processed food (UPF) consumption and (i) symptomatic disease and (ii) intestinal inflammation among adults with inflammatory bowel disease (IBD). METHODS: We identified participants (Crohn's disease [CD] and ulcerative colitis [UC]) from the Manitoba Living with IBD study. Active disease was defined using the IBD Symptom Inventory (score >14 for CD; >13 for UC); fecal calprotectin was measured for intestinal inflammation (>250 µg/g). Diet data were collected using the Harvard Food Frequency Questionnaire. UPF consumption was determined by the NOVA classification system. Percentage of energy consumption from UPFs was calculated and divided into 3 tertiles (T1 = low; T3 = high). Multiple linear regression analysis was used for active disease and inflammation predicted by UPF consumption. RESULTS: Among 135 participants (65% with CD), mean number of episodes of active disease (14.2 vs 6.21) and active inflammation (1.6 vs 0.6) was significantly higher among participants with UC in T3 compared with T1 of UPF consumption ( P < 0.05). When adjusting for age, sex, disease type, and duration, number of episodes of active disease was lower in T1 compared with T3 (ß = -7.11, P = 0.02); similarly, number of episodes of intestinal inflammation was lower in T1 (ß = -0.95, P = 0.03). No significant differences were observed among participants with CD. DISCUSSION: UPF consumption may be a predictor of active symptomatic disease and inflammation among participants with UC. Reducing UPF consumption is a dietary strategy that can be suggested for minimizing symptoms and inflammation among people living with IBD.

Forecasting the Incidence and Prevalence of Inflammatory Bowel Disease: A Canadian Nationwide Analysis.

INTRODUCTION: Canada has a high burden of inflammatory bowel disease (IBD). Historical trends of IBD incidence and prevalence were analyzed to forecast the Canadian burden over the next decade. METHODS: Population-based surveillance cohorts in 8 provinces derived from health administrative data assessed the national incidence (2007-2014) and prevalence (2002-2014) of IBD. Autoregressive integrated moving average models were used to forecast incidence and prevalence, stratified by age, with 95% prediction intervals (PI), to 2035. The average annual percentage change (AAPC) with 95% confidence interval (CI) was calculated for the forecasted incidence and prevalence. RESULTS: The national incidence of IBD is estimated to be 29.9 per 100,000 (95% PI 28.3-31.5) in 2023. With a stable AAPC of 0.36% (95% CI -0.05 to 0.72), the incidence of IBD is forecasted to be 31.2 per 100,000 (95% PI 28.1-34.3) in 2035. The incidence in pediatric patients (younger than 18 years) is increasing (AAPC 1.27%; 95% CI 0.82-1.67), but it is stable in adults (AAPC 0.26%; 95% CI -0.42 to 0.82). The prevalence of IBD in Canada was 843 per 100,000 (95% PI 716-735) in 2023 and is expected to steadily climb (AAPC 2.43%; 95% CI 2.32-2.54) to 1,098 per 100,000 (95% PI 1,068-1,127) by 2035. The highest prevalence is in seniors with IBD (1,174 per 100,000 in 2023; AAPC 2.78%; 95% CI 2.75-2.81). DISCUSSION: Over the next decade, the Canadian health care systems will contend with the juxtaposition of rising incidence of pediatric IBD and a rising prevalence of overall IBD driven by the aging population.

When Should I Get My Next COVID-19 Vaccine? Data From the Surveillance of Responses to COVID-19 Vaccines in Systemic Immune-Mediated Inflammatory Diseases (SUCCEED) Study.

OBJECTIVE: To determine how serologic responses to coronavirus disease 2019 (COVID-19) vaccination and infection in immune-mediated inflammatory disease (IMID) are affected by time since last vaccination and other factors. METHODS: Post-COVID-19 vaccination, data, and dried blood spots or sera were collected from adults with rheumatoid arthritis, inflammatory bowel disease, systemic lupus erythematosus, ankylosing spondylitis and spondylarthritis, and psoriasis and psoriatic arthritis. The first sample was collected at enrollment, then at 2 to 4 weeks and 3, 6, and 12 months after the latest vaccine dose. Multivariate generalized estimating equation regressions (including medications, demographics, and vaccination history) evaluated serologic response, based on log-transformed anti-receptor-binding domain (RBD) IgG titers; we also measured antinucleocapsid (anti-N) IgG. RESULTS: Positive associations for log-transformed anti-RBD titers were seen with female sex, number of doses, and self-reported COVID-19 infections in 2021 to 2023. Negative associations were seen with prednisone, anti-tumor necrosis factor agents, and rituximab. Over the 2021-2023 period, most (94%) of anti-N positivity was associated with a self-reported infection in the 3 months prior to testing. From March 2021 to February 2022, anti-N positivity was present in 5% to 15% of samples and was highest in the post-Omicron era, with antinucleocapsid positivity trending to 30% to 35% or higher as of March 2023. Anti-N positivity in IMID remained lower than Canada's general population seroprevalence (> 50% in 2022 and > 75% in 2023). Time since last vaccination was negatively associated with log-transformed anti-RBD titers, particularly after 210 days. CONCLUSION: Ours is the first pan-Canadian IMID assessment of how vaccine history and other factors affect serologic COVID-19 vaccine responses. These findings may help individuals personalize vaccination decisions, including consideration of additional vaccination when > 6 months has elapsed since last COVID-19 vaccination/infection.

Hormonal Contraceptives Reduce Active Symptomatic Disease but May Increase Intestinal Inflammation in IBD.

BACKGROUND: Among women of reproductive age with inflammatory bowel disease (IBD), we aimed to assess the relationship of hormonal contraceptives (HCs) with IBD-related symptoms, and intestinal inflammation. METHODS: A nested cohort of women in the longitudinal Manitoba Living with IBD Study, ages 18 to 49, were followed for 1 year, with bi-weekly online surveys. This included a validated measure of disease activity; IBD Symptom Inventory (IBDSI), and stool samples obtained at 3 time-points for assessment of fecal calprotectin (FCAL). Use of HC included oral and vaginal intrauterine devices. Logistic regression analysis was used to assess the association between HC and IBD-related symptoms (IBDSI>14 for Crohn disease, >13 for ulcerative colitis), or inflammation (FCAL>250 ug/g) at any measurement point in the study. RESULTS: Of 71 women, 17 (24%) reported taking HC in the 1 year period. Adjusting for age, disease type, disease duration, and smoking status, the odds of having increased IBD-related symptoms (IBDSI) during the year were lower for women using HC compared with women not using HC [adjusted odds ratio 0.16, 95% CI, 0.02-0.90]. Conversely, women using HC were more likely to have inflammation during the year [adjusted odds ratio 5.7, 95% CI, 1.23-43.6]. CONCLUSIONS: HC use among women with IBD was associated with a lower likelihood of IBD-related symptoms but a higher likelihood of experiencing intestinal inflammation (FCAL>250 ug/g) over 1 year. Further work is needed to examine this dichotomous result, potentially examining aspects such as duration of HC use, and the types of HC.

Physician perspectives of Helicobacter pylori diagnostic and treatment practices in Canada: results of a Canadian survey.

BACKGROUND: Helicobacter pylori infection is prevalent worldwide and can lead to peptic ulcer disease (PUD) and gastric cancer. Effective diagnosis and treatment of H. pylori infection by gastroenterologists and family physicians is crucial. However, there are differing views on optimal diagnosis and treatment. The objective of this study is to understand the impressions of Canadian physicians regarding H. pylori diagnosis and treatment and whether impressions differ between gastroenterologists and family physicians. A second objective is to understand physician perspectives on rising antibiotic resistance and how that guides empiric management. METHODS: A survey facilitated via REDCap was administered to Canadian gastroenterologists and family physicians. A total of 105 participants completed the survey, including 43 gastroenterologists and 62 family physicians. Gastroenterologists were recruited from across the country and family physicians were recruited from Manitoba. RESULTS: For diagnosis of H. pylori, 67% of gastroenterologists reported endoscopic biopsies for histology assessment as most common and 73% of family physicians reported serology as their main diagnostic test. While nearly all gastroenterologists believed antibiotic resistance to be a problem, nearly one quarter of family physicians did not believe it was a problem. CONCLUSIONS: There is variability in practices among both gastroenterologists and family physicians regarding diagnosis of H. pylori infection. There was consensus that local antibiotic resistance patterns should guide management. If known, the degree and patterns of antibiotic resistance could bring a more uniform consensus to H. pylori management. Greater education of physicians, especially family physicians regarding management of H pylori is needed.

The impact of source and consumption of news on mental distress among inflammatory bowel disease patients during the COVID-19 pandemic.

Background: We sought to understand the trends in media use, and how consumption and source affected mental health of persons with inflammatory bowel disease during the early parts of the pandemic. Dissemination of news during the coronavirus disease 2019 (COVID-19) pandemic was integral to educating the public but also could be harmful if constantly consumed, leading to worsening anxiety. Methods: We performed a survey study in autumn 2020 during the second wave of COVID-19 in Manitoba. The survey included questions on consumption of COVID-19 news, along with validated measures of perceived stress, generalized anxiety, health anxiety, and depression. We used multivariable logistic regression analysis to assess trusted sources of news as a predictor of clinically significant mental health symptoms. Results: Of the 2940 participants in the registry, 1384 (47.1%) persons responded. The most trusted sources of news were television (64.2%), internet (46.1%), newspaper (27.6%), friends/family (21.7%), social media (16.9%), and radio (16.6%). Those who trusted social media had higher odds of depression (aOR 1.52, 95%CI 1.04-2.22), and perceived stress (aOR 2.56, 95%CI 1.09-2.21). Persons who reported extreme difficulty limiting their time-consuming news about COVID-19 and who spent more than 1 h daily consuming information on COVID-19 both had increased odds of any clinically significant mental health symptoms. Conclusions: It is unknown if consumption of COVID-19 news led to heightened mental health symptoms or if increasing anxieties and concerns led to consuming more news. Further research is needed to assess whether these elevated mental health symptoms led to worse disease outcomes.

A randomized trial evaluating the utility of non-targeted biopsies for colorectal neoplasia detection in adults with inflammatory bowel disease: a pilot study protocol.

BACKGROUND: Persons with inflammatory bowel diseases are at increased risk of developing colorectal cancer and require frequent colonoscopy surveillance. Guidelines recommend taking 30 to 40 non-targeted biopsies throughout the colorectum to detect "invisible" neoplasia in this setting, despite a lack of evidence supporting this practice. We sought to assess the utility of this practice through a randomized controlled trial. We first propose an internal pilot study to assess recruitment potential, protocol adherence and data capture to guide the full trial. METHODS: We have designed a multi-centre, parallel-group, non-inferiority randomized controlled trial to test the utility of non-targeted biopsies as an adjunct to colonoscopy surveillance for neoplasia detection in persons with inflammatory bowel disease involving the colorectum in routine clinical practice. Participants are randomized 1:1, stratified by study site, to either standard of care high-definition white-light colonoscopy with 32 to 40 non-targeted biopsies of non-neoplastic-appearing mucosa along with a sampling of abnormal-appearing mucosa (control group) or modified colonoscopy with targeted sampling alone (intervention group). The primary outcome for the full trial will be the proportion of persons with ≥ 1 neoplastic focus detected during colonoscopy. For the pilot phase, we will assess the feasibility of recruiting a minimum of 15% of the estimated sample size within 1 year, under identical conditions as the full trial, while maintaining ≥ 90-95% rate of protocol adherence and data capture. These participants will contribute data to the full trial. The trial is being conducted at 12 centres across Canada, with a total sample size of 1952 persons. DISCUSSIONS: The trial protocol has been approved by the ethics committees of all participating sites, and the pilot study has received funding through the Canadian Institutes of Health Research (PJT 159607). If feasibility metrics are met during the pilot phase, we will complete the full trial. The trial outcomes will contribute to update the practice guidelines in this area. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04067778.

Patient preferences for active ulcerative colitis treatments and fecal microbiota transplantation.

Background: Fecal microbiota transplantation (FMT) is a promising treatment for active ulcerative colitis (UC). Understanding patient preferences can identify treatment features that may impact treatment decisions, improve shared decision-making, and contribute to patient-centered care, which is especially important in the context of novel treatments like FMT. Objectives: We aimed to quantify preferences for active UC treatments, specifically FMT and biologics, and identify patient characteristics associated with different preference patterns. Design: This is a cross-sectional survey study. Methods: We administered a discrete choice experiment (DCE) survey to elicit preferences in a sample of Canadian adults with UC. DCE data were analyzed using a main-effects mixed logit model and used to predict uptake of hypothetical scenarios reflecting alternative combinations of treatment features. Latent class modeling identified heterogeneity in patient preference patterns. Results: Participants' (n = 201) mean age was 47.1 years (SD: 14.5 years), 58% were female, and most (84%) had at least some post-secondary education. Almost half were willing to undergo FMT. When considering treatments for active UC, the most important attributes were chance of remission and severity of rare unknown side effects. All else equal, participants were most likely to uptake treatment that involves oral capsules/pills. Participants in the class with the highest utility for chance of remission were younger, had more severe disease, and 58% indicated that they would be willing to undergo FMT. Conclusion: We identified characteristics of UC patients who are more likely to be interested in FMT using preference elicitation methods. Patient-centered care can be enhanced by knowing which patients are more likely to be interested in FMT, potentially improving satisfaction with and adherence to treatments for active UC to maximize the effectiveness of treatment while considering heterogeneity in patient preferences.

Background and aims: Fecal microbiota transplantation (FMT) is a promising new treatment for active ulcerative colitis. Questions remain around the benefits and risks of FMT treatment for patients with ulcerative colitis. Understanding how patients weigh the treatment features and how treatment features influence their decisions may improve shared decision-making and contribute to patient-centered care, which is especially important for novel treatments like FMT.Using an experimentally designed survey, we aimed to:1. Elicit patient preferences for features of active ulcerative colitis treatments, specifically FMT and biologics; and,2. Identify patient characteristics associated with different preference patterns. Results: We found that younger patients with more severe disease are more likely to try FMT for the treatment of active ulcerative colitis. Oral capsules/pills are the preferred mode of treatment administration. Conclusions: These findings can enhance patient-centered care by characterizing patients who are more likely to be interested in FMT. Aligning treatment with the features that are important to patients can potentially improve satisfaction with and adherence to treatments for active ulcerative colitis to maximize their effectiveness for individual patients.

Patient preferences for active ulcerative colitis treatments and fecal microbiota transplantation.

Assessment of dietary intake and its inflammatory potential in persons with pediatric-onset multiple sclerosis.

OBJECTIVE: To compare diet and the modified dietary inflammatory index (mDII) between individuals with pediatric-onset multiple sclerosis (PoMS), monophasic acquired demyelinating syndromes (monoADS), and controls. METHODS: The association between diet, mDII, and disease status was examined in 131 individuals with PoMS/monoADS/controls (38/45/48) using logistic regression. RESULTS: The associations between diet and PoMS were modest, reaching significance for whole grain intake (adjusted odds ratio, aOR=0.964, 95 % confidence intervals, CI:0.934-0.995) but not mDII (aOR=1.20, 95 %CI:0.995-1.46) versus controls. No findings for monoADS reached significance versus controls. CONCLUSIONS: Individuals with PoMS, but not monoADS, had lower dietary whole grain intake than controls.

Crohn's Disease Phenotypes and Associations With Comorbidities, Surgery Risk, Medications and Nonmedication Approaches: The MAGIC in IMAGINE Study.

BACKGROUND: We aimed to establish a cohort of persons with Crohn's disease (CD) enrolled from 14 Canadian centers to describe the contemporary presentation of CD in Canada. METHODS: All enrollees were at least 18 years old and underwent chart review for phenotype documentation by Montreal Classification at time of enrollment, comorbidities, inflammatory bowel disease (IBD) and other surgeries, and use IBD and other therapies. RESULTS: Of 2112 adults, 59% were female, and the mean age was 44.1 (+/-14.9SD) years. The phenotype distribution was B1 = 50.4%, B2 = 22.4%, B3 = 17.3%, and missing information = 9.9%. Perineal disease was present in 14.2%. Pertaining to disease location, 35.2% of patients had disease in L1, 16.8% in L2, 48% in L3, and 0.4% in L4. There was no difference in phenotype by gender, anxiety score, depression score. Disease duration was significantly different depending on disease behavior type (B1 = 12.2 ±â€…10.1; B2 = 19.4 ±â€…12.9; B3 = 18.9 ±â€…11.8, P < .0001). Isolated colonic disease was much less likely to be fibrostenotic or penetrating than inflammatory disease. Penetrating disease was more likely to be associated with ileocolonic location than other locations. Perineal disease was most commonly seen in persons with B3 disease behavior (24%) than other behaviors (11% B1; 20% B2 disease, P < .0001) and more likely to be seen in ileocolonic disease (L3;19%) vs L2 (17%) and L1 (11%; P < .0001). Surgery related to IBD occurred across each behavior types at the following rates: B1 = 23%, B2 = 64%, and B3 = 74%. Inflammatory bowel disease-related surgery rates by location of disease were L1 = 48%, L2 = 21%, and L3 = 51%. CONCLUSIONS: In exploring this large contemporary CD cohort we have determined that inflammatory disease is the main CD phenotype in Canada and that CD-related surgery remains very common.

Duration of Postvaccination Neutralizing Antibodies to SARS-CoV-2 and Medication Effects: Results from the Safety and Immunogenicity of COVID-19 Vaccination in Systemic Immune-Mediated Inflammatory Diseases Cohort Study.

OBJECTIVE: In the face of the ongoing circulation of SARS-CoV-2, the durability of neutralization post-COVID-19 vaccination in immune-mediated inflammatory disease (IMID) is a key issue, as are the effects of medications. METHODS: Adults (n = 112) with inflammatory bowel disease, psoriasis/psoriatic arthritis, rheumatoid arthritis, spondylarthritis, and systemic lupus were recruited from participating Canadian medical centers from 2021 to 2023. We focused on log-transformed neutralization (lentivirus methods) as a continuous outcome, with separate models for wild-type and Omicron strains BA.1 and BA.5. RESULTS: Compared with 30 to 120 days postvaccination, subsequent periods were associated with greater neutralization in unadjusted models for wild-type, BA.1, and BA.5 strains and against the BA.1 strain in adjusted models. Rituximab was associated with lower neutralization for the BA.1 strain in adjusted models, with a similar trend for BA.5. In methotrexate users, there were trends for less neutralization of BA.1 and BA.5 in all unadjusted models, whereas in adjusted models, there was significantly lower neutralization only for the wild type. Three or more doses and Omicron-specific vaccines were both independently associated with better neutralization ability for all three strains. A COVID-19 infection within six months before sampling was associated with higher neutralization of wild type and BA.1 in adjusted analyses. Anti-tumor necrosis factor agents were associated with lower neutralization ability for BA.5 in adjusted analyses. CONCLUSION: Neutralization responses in immunosuppressed individuals with IMID were durable over time and were augmented by more than three doses and Omicron-specific vaccines. Less neutralization was seen with certain medications. Our work clarifies the joint effects of vaccine history, infection, and medications on COVID-19 immunity.

High Healthcare Costs in Childhood Inflammatory Bowel Disease: Development of a Prediction Model Using Linked Clinical and Health Administrative Data.

BACKGROUND: The incidence of pediatric-onset inflammatory bowel disease (IBD) and the costs of caring for individuals with IBD are both increasing. We calculated the direct healthcare costs of pediatric IBD in the first year after diagnosis and developed a model to predict children who would have high costs (top 25th percentile). METHODS: Using data from the Canadian Children IBD Network inception cohort (≤16 years of age, diagnosed between 2013 and 2019) deterministically linked to health administrative data from Ontario, Canada, we estimated direct healthcare and medication costs accrued between 31 and 365 days after diagnosis. Candidate predictors included age at diagnosis, sex, rural/urban residence location, distance to pediatric center, neighborhood income quintile, IBD type, initial therapy, disease activity, diagnostic delay, health services utilization or surgery around diagnosis, regular primary care provider, and receipt of mental health care. Logistic regression with stepwise elimination was used for model building; 5-fold nested cross-validation optimized and improved model accuracy while limiting overfitting. RESULTS: The mean cost among 487 children with IBD was CA$15 168 ± 15 305. Initial treatment (anti-tumor necrosis factor therapy, aminosalicylates, or systemic steroids), having a mental health care encounter, undergoing surgery, emergency department visit at diagnosis, sex, and age were predictors of increased costs, while having a regular primary care provider was a predictor of decreased costs. The C-statistic for our model was 0.71. CONCLUSIONS: The cost of caring for children with IBD in the first year after diagnosis is immense and can be predicted based on characteristics at diagnosis. Efforts that mitigate rising costs without compromising quality of care are needed.

Cost of caring for children with IBD is high­CA$15 168 between 31 and 365 days from diagnosis in 487 Canadian children. Predictors of high costs included anti-tumor necrosis factor therapy and mental health care, with lower costs in those with a primary-care provider.

A cross-sectional study of MRI features and the gut microbiome in pediatric-onset multiple sclerosis.

OBJECTIVE: To identify gut microbiome features associated with MRI lesion burden in persons with pediatric-onset multiple sclerosis (symptom onset <18 years). METHODS: A cross-sectional study involving the Canadian Paediatric Demyelinating Disease Network study participants. Gut microbiome features (alpha diversity, phylum- and genus-level taxa) were derived using 16S rRNA sequencing from stool samples. T1- and T2-weighted lesion volumes were measured on brain MRI obtained within 6 months of stool sample procurement. Associations between the gut microbiota and MRI metrics (cube-root-transformed) were assessed using standard and Lasso regression models. RESULTS: Thirty-four participants were included; mean ages at symptom onset and MRI were 15.1 and 19.0 years, respectively, and 79% were female. The T1- and T2-weighted lesion volumes were not significantly associated with alpha diversity (age and sex-adjusted p > 0.08). At the phylum level, high Tenericutes (relative abundance) was associated with higher T1 and T2 volumes (ß coefficient = 0.25, 0.37) and high Firmicutes, Patescibacteria or Actinobacteria with lower lesion volumes (ß coefficient = -0.30 to -0.07). At the genus level, high Ruminiclostridium, whereas low Coprococcus 3 and low Erysipelatoclostridium were associated with higher lesion volumes. INTERPRETATION: Our study characterized the gut microbiota features associated with MRI lesion burden in pediatric-onset MS, shedding light onto possible pathophysiological mechanisms.

Mediterranean diet and associations with the gut microbiota and pediatric-onset multiple sclerosis using trivariate analysis.

BACKGROUND: The interplay between diet and the gut microbiota in multiple sclerosis (MS) is poorly understood. We aimed to assess the interrelationship between diet, the gut microbiota, and MS. METHODS: We conducted a case-control study including 95 participants (44 pediatric-onset MS cases, 51 unaffected controls) enrolled from the Canadian Pediatric Demyelinating Disease Network study. All had completed a food frequency questionnaire ≤21-years of age, and 59 also provided a stool sample. RESULTS: Here we show that a 1-point increase in a Mediterranean diet score is associated with 37% reduced MS odds (95%CI: 10%-53%). Higher fiber and iron intakes are also associated with reduced MS odds. Diet, not MS, explains inter-individual gut microbiota variation. Several gut microbes abundances are associated with both the Mediterranean diet score and having MS, and these microbes are potential mediators of the protective associations of a healthier diet. CONCLUSIONS: Our findings suggest that the potential interaction between diet and the gut microbiota is relevant in MS.

Multiple sclerosis (MS) is a disease where the immune system attacks the protective covering of nerve cells in the brain. There may be a relationship between diet and bacteria within the gut and MS, however this is not well understood. We investigated how diet and gut bacteria are linked to MS in young people. We examined the diet and types of bacteria in stool samples from those with and without MS. We found that a diet richer in fiber and Mediterranean foods were less common in those with MS. This dietary pattern was linked to certain differences in the gut bacteria. These findings raise the possibility, but cannot prove, that what we eat may help prevent MS by influencing our gut bacteria. This research opens the door to further studies on how diet can impact MS through our gut bacteria.

Polygenic liability for anxiety in association with comorbid anxiety in multiple sclerosis.

OBJECTIVE: Comorbid anxiety occurs often in MS and is associated with disability progression. Polygenic scores offer a possible means of anxiety risk prediction but often have not been validated outside the original discovery population. We aimed to investigate the association between the Generalized Anxiety Disorder 2-item scale polygenic score with anxiety in MS. METHODS: Using a case-control design, participants from Canadian, UK Biobank, and United States cohorts were grouped into cases (MS/comorbid anxiety) or controls (MS/no anxiety, anxiety/no immune disease or healthy). We used multiple anxiety measures: current symptoms, lifetime interview-diagnosed, and lifetime self-report physician-diagnosed. The polygenic score was computed for current anxiety symptoms using summary statistics from a previous genome-wide association study and was tested using regression. RESULTS: A total of 71,343 individuals of European genetic ancestry were used: Canada (n = 334; 212 MS), UK Biobank (n = 70,431; 1,390 MS), and the USA (n = 578 MS). Meta-analyses identified that in MS, each 1-SD increase in the polygenic score was associated with ~50% increased odds of comorbid moderate anxious symptoms compared to those with less than moderate anxious symptoms (OR: 1.47, 95% CI: 1.09-1.99). We found a similar direction of effects in the other measures. MS had a similar anxiety genetic burden compared to people with anxiety as the index disease. INTERPRETATION: Higher genetic burden for anxiety was associated with significantly increased odds of moderate anxious symptoms in MS of European genetic ancestry which did not differ from those with anxiety and no comorbid immune disease. This study suggests a genetic basis for anxiety in MS.