Practical guidance for managing patients with moderate-to-severe ulcerative colitis using small molecule therapies.

Ulcerative colitis (UC) is a severe and debilitating illness that affects the quality of life and physical health of many Canadians. Given the dynamic and progressive nature of the disease, advanced therapies are required to support its long-term management. The emergence of small molecule therapies offers novel treatment options that target mechanisms central to the immunopathology of UC. Sphingosine-1-phosphate (S1P) receptor modulators and Janus-activated kinase inhibitors are 2 classes of therapies that target unique pathways to attenuate inflammation and modulate the immune response characteristic of UC. This review aims to provide practical guidance on how these therapeutic options can best be used to optimize treatment management and highlight the emerging role of small molecule therapies as a treatment strategy for UC.

Outcomes of patients admitted with acute, severe ulcerative colitis on biologic therapy: a retrospective analysis from a tertiary referral hospital.

Background: In steroid-refractory acute, severe, ulcerative colitis (ASUC), salvage medical therapy with infliximab is recommended to reduce the risk of colectomy. However, the evidence supporting this practice is based on cohorts naïve to biologics. Consequently, the management of patients on biologic or small molecule therapy (BST) with ASUC is not well defined. Methods: We conducted a retrospective chart review of patients admitted with ASUC to Mount Sinai Hospital (MSH) in Toronto, Ontario from January 2018 until January 2022. Included subjects were considered to be on BST if they had received a dose of these agents within 56 days prior to admission. Our outcomes of interest included the mean difference in hospital length of stay (HLOS), rates of surgical consultation, rates of inpatient colectomies, and 90-day readmission rates between the 2 groups. Results: Of the 185 admissions for ASUC, 76 were on BST prior to admission and 109 were not. Baseline characteristics were similar between the 2 groups. There were no significant differences in hospital length of stay (7.46 days vs 7.45 days P = .52) or in-hospital colectomy rates between the 2 groups. Patients on BST had higher rates of surgical consultation (36.8% vs 8.3% P < .01) and 90-day readmission rates (26.3% vs 13.8% P = .03). Conclusions: We did not identify significant differences in the majority of our outcomes between the 2 groups. However, patients on BST were more likely to receive a surgical consultation during their admission and had higher rates of readmission at 90 days. Further studies evaluating the underlying factors that contribute to readmission in patients on BST in hospitals are needed.

A Population-Based Matched Cohort Study of Digestive System Cancer Incidence and Mortality in Individuals With and Without Inflammatory Bowel Disease.

INTRODUCTION: To study digestive system cancer risks in individuals with inflammatory bowel diseases (IBDs) in the biologic era. METHODS: We used population-level administrative and cancer registry data from Ontario, Canada, (1994-2020) to compare people with IBD to matched controls (1:10 by sex and birth year) on trends in age-sex standardized cancer incidence and risk ratios of incident cancers and cancer-related deaths. RESULTS: Among 110,919 people with IBD and 1,109,190 controls, colorectal cancer incidence (per 100,000 person-years) declined similarly in people with ulcerative colitis (average annual percentage change [AAPC] -1.81; 95% confidence interval [CI] -2.48 to -1.156) and controls (AAPC -2.79; 95% CI -3.44 to -2.14), while small bowel cancer incidence rose faster in those with Crohn's disease (AAPC 9.68; 95% CI 2.51-17.3) than controls (AAPC 3.64; 95% CI 1.52-5.80). Extraintestinal digestive cancer incidence rose faster in people with IBD (AAPC 3.27; 95% CI 1.83-4.73) than controls (AAPC -1.87; 95% CI -2.33 to -1.42), particularly for liver (IBD AAPC 8.48; 95% CI 4.11-13.1) and bile duct (IBD AAPC 7.22; 95% CI 3.74-10.8) cancers. Beyond 2010, the incidences (and respective mortality rates) of colorectal (1.60; 95% CI 1.46-1.75), small bowel (4.10; 95% CI 3.37-4.99), bile duct (2.33; 95% CI 1.96-2.77), and pancreatic (1.19; 95% CI 1.00-1.40) cancers were higher in people with IBD. DISCUSSION: Cancer incidence is declining for colorectal cancer and rising for other digestive cancers in people with IBD. Incidence and mortality remain higher in people with IBD than controls for colorectal, small bowel, bile duct, and pancreatic cancers.

Considerations in gender-affirming hormone therapy in transgender and gender diverse patients undergoing liver transplantation.

Liver transplantation is lifesaving for patients with end-stage liver disease. Similar to the role of transplantation for patients with end-stage liver disease, gender-affirming hormone therapy (GAHT) can be lifesaving for transgender and gender diverse (TGGD) patients who experience gender dysphoria. However, management of such hormone therapy during the perioperative period is unknown and without clear guidelines. Profound strides can be made in improving care for TGGD patients through gender-affirming care and appropriate management of GAHT in liver transplantation. In this article, we call for the transplant community to acknowledge the integral role of GAHT in the care of TGGD liver transplant candidates and recipients. We review the current literature and describe how the transplant community is ethically obligated to address this health care gap. We suggest tangible steps that clinicians may take to improve health outcomes for this minoritized patient population.

Proportion of inflammatory bowel diseases patients with suboptimal disease control in daily clinical practice-Real-world evidence from the inflammatory bowel diseases-podcast study.

BACKGROUND: Crohn's disease and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) characterized by a progressive nature of the disease resulting in subsequent intestinal damage, limited efficacy of current treatments and suboptimal disease management and a significant burden for patients. OBJECTIVES: The IBD-PODCAST study aims to estimate the proportion of Crohn's disease and UC patients with suboptimal disease control (SDC) in a real-world setting. METHODS: A non-interventional and cross-sectional study was conducted across 103 sites in 10 countries (Austria, Belgium, Canada, Germany, Greece, Italy, Portugal, Spain, Turkey, and UK). Criteria for SDC were based on STRIDE-II criteria and adapted by an expert panel. RESULTS: 2185 patients (Crohn's disease: n = 1,108, UC: n = 1077) with a mean (SD) age of 44.0 (14.8) years and mean (SD) disease duration of 12.4 (9.2) years were included (52.2% male). Ileal involvement was present in 39.1% of Crohn's disease patients, 35.3% of UC patients had extensive colitis. 77.3% of Crohn's disease and 65.3% of UC patients were on targeted immunomodulators and, according to STRIDE-II-based treatment phases, 85.6% of Crohn's disease and 85.4% of UC patients were assigned to the long-term treatment phase. SDC was detected in 52.2% of Crohn's disease and 44.3% of UC patients predominantly due to impaired quality of life (QoL), clinically significant extraintestinal manifestations, steroid overuse, signs of active inflammation in UC and Crohn's disease, and active fistulas in Crohn's disease. More than one criterion was seen in 37% of patients with SDC. Opportunities for on-label treatment optimization were observed in 49% of Crohn's disease and 61% of UC patients on advanced therapy. CONCLUSION: The high percentage of SDC in this global, real-world cohort suggests a large disease burden and high unmet medical need in IBD patients. Future analysis should focus on monitoring and responding to SDC in this cohort and on patients' QoL.

Risk of Cesarean Delivery Among People With Inflammatory Bowel Disease According to Disease Characteristics: A Population-Based Study.

OBJECTIVES: It is unclear if use of cesarean delivery in people with inflammatory bowel disease (IBD) is guideline-concordant. We compared the odds of cesarean delivery among primiparous individuals with IBD versus without, overall, and by disease characteristics, as well as time to subsequent delivery. METHODS: Retrospective matched population-based cohort study between 1 April 1994 and 31 March 2020. Primiparous individuals aged 15-55 years with IBD were matched to those without IBD on age, year, hospital, and number of newborns delivered. Primary outcome was cesarean delivery versus vaginal delivery. Multivariable conditional logistic regression analyses were performed to estimate the odds of cesarean delivery among individuals with and without IBD as a binary exposure, and a categorical exposure based on IBD-related indications for cesarean delivery. Time to subsequent delivery was evaluated using a Cox proportional hazard model. RESULTS: We matched 7472 individuals with IBD to 37 360 individuals without (99.02% match rate). Individuals with IBD were categorised as having perianal (PA) disease (IBD-PA, n = 764, 10.2%), prior ileal pouch-anal anastomosis (n = 212, 2.8%), or IBD-Other (n = 6496, 86.9%). Cesarean delivery rates were 35.4% in the IBD group versus 30.4% in their controls (adjusted odds ratio 1.27; 95% CI 1.20-1.34). IBD-ileal pouch-anal anastomosis had a cesarean delivery rate of 66.5%, compared to 49.9% in IBD-PA and 32.7% in IBD-Other. There was no significant difference in the rate of subsequent delivery in those with and without IBD (adjusted hazard ratio 1.03; 95% CI 1-1.07). CONCLUSIONS: The higher risk of cesarean delivery in people with IBD reflects guideline-concordant use. Individuals with and without IBD were equally likely to have a subsequent delivery with similar timing.

Comparing the efficacy of vedolizumab between males and females: a post-hoc analysis of GEMINI-1 and VARSITY.

Vedolizumab is a first-line treatment option for ulcerative colitis. There are differences in incidence of ulcerative colitis between males and females, but whether sex affects treatment outcomes is less clear. We examined sex-based differences in patients with ulcerative colitis initiated on vedolizumab from two major randomized controlled trials (RCTs). We conducted a post-hoc analysis on participants with ulcerative colitis from the VARSITY and GEMINI-1 RCTs who received vedolizumab. Outcomes of interest were rates of clinical improvement, clinical remission, and endoscopic improvement at weeks 6, 14, and 52 in male and female participants, as were differences in concentrations of trough vedolizumab and C-reactive protein; 1009 persons in GEMINI-1 and VARSITY trials were included. Male and female patients had similar disease characteristics aside from males being more likely to have Mayo 3 grade endoscopic severity at baseline (62.8 vs. 48.9%, P  < 0.001). At week 6, females were more likely to have endoscopic improvement (47.4 vs. 35.2%, P  = 0.001) and increased vedolizumab trough levels [34.0 (23.0-44.5) vs. 28.9 (19.0-34.6), P  < 0.001]. The probability of achieving clinical remission (28.9 vs. 34.5%, P  = 0.057) or endoscopic improvement (35.5 vs. 39.3%, P  = 0.212) at week 52 was not different between males and females. Females with ulcerative colitis treated with vedolizumab appear more likely to achieve early endoscopic improvement than males, though longer-term outcomes demonstrated no difference. Further studies are required to better understand mechanisms through which sex or sex-associated factors could influence response to therapy in ulcerative colitis.

Effect of Suboptimal Disease Control on Patient Quality of Life: Real-World Data from the Observational IBD-PODCAST Canada Trial.

BACKGROUND: The real-world application of STRIDE-II treatment targets to identify whether disease control is optimal in Crohn's disease (CD) and ulcerative colitis (UC) is not well known. AIMS: This study aimed to estimate proportions of patients with suboptimally controlled CD and UC in real-world Canadian healthcare settings and the impact on quality of life (QoL). METHODS: The noninterventional, multicenter, observational IBD-PODCAST Canada study comprised a single study visit involving routine assessments, patient- and clinician-completed questionnaires, and a retrospective chart review. Primary outcomes were proportions of patients with STRIDE-II-based red flags indicative of suboptimal disease control and mean ± standard deviation Short Inflammatory Bowel Disease Questionnaire (SIBDQ) scores. Secondary outcomes included proportions of patients and clinicians subjectively reporting suboptimal control. RESULTS: Among 163 enrolled patients from 10 sites, 45/87 patients with CD (51.7%; 95% CI: 40.8%, 62.6%) and 33/76 patients with UC (43.3%; 95% CI: 32.1%, 55.3%) had suboptimal disease control based on STRIDE-II criteria. Suboptimal control was subjectively reported at lower proportions (patients: CD, 15.0%; UC, 18.6%; clinicians: CD, 19.5%; UC, 25.0%). Numerically lower SIBDQ scores were observed with suboptimal control (CD, 43.0 ± 10.8; UC, 42.5 ± 12.0) than with optimal control (CD, 58.2 ± 7.2; UC, 57.8 ± 6.6). CONCLUSIONS: Approximately 50% (CD) and 40% (UC) of patients from real-world Canadian practices had suboptimal disease control based on STRIDE-II criteria. Suboptimal control was underestimated by patients and clinicians and accompanied by reduced QoL, suggesting further efforts to implement STRIDE-II treat-to-target strategies are needed.

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.

Health Services Utilization and Specialist Care in Pediatric Inflammatory Bowel Disease: A Multiprovince Population-Based Cohort Study.

BACKGROUND: Patterns of health services utilization among children with inflammatory bowel disease (IBD) are important to understand as the number of children with IBD continues to increase. We compared health services utilization and surgery among children diagnosed <10 years of age (Paris classification: A1a) and between 10 and <16 years of age (A1b). METHODS: Incident cases of IBD diagnosed <16 years of age were identified using validated algorithms from deterministically linked health administrative data in 5 Canadian provinces (Alberta, Manitoba, Nova Scotia, Ontario, Quebec) to conduct a retrospective cohort study. We compared the frequency of IBD-specific outpatient visits, emergency department visits, and hospitalizations across age groups (A1a vs A1b [reference]) using negative binomial regression. The risk of surgery was compared across age groups using Cox proportional hazards models. Models were adjusted for sex, rural/urban residence location, and mean neighborhood income quintile. Province-specific estimates were pooled using random-effects meta-analysis. RESULTS: Among the 1165 (65.7% Crohn's) children with IBD included in our study, there were no age differences in the frequency of hospitalizations (rate ratio [RR], 0.88; 95% confidence interval [CI], 0.74-1.06) or outpatient visits (RR, 0.95; 95% CI, 0.78-1.16). A1a children had fewer emergency department visits (RR, 0.70; 95% CI, 0.50-0.97) and were less likely to require a Crohn's-related surgery (hazard ratio, 0.49; 95% CI, 0.26-0.92). The risk of colectomy was similar among children with ulcerative colitis in both age groups (hazard ratio, 0.71; 95% CI, 0.49-1.01). CONCLUSIONS: Patterns of health services utilization are generally similar when comparing children diagnosed across age groups.

Among 1165 children with inflammatory bowel disease, health services utilization was similar for children diagnosed <10 years of age and those diagnosed ≥10 years of age, except younger children had fewer emergency department visits and Crohn's disease­related surgeries.

Variation in the Care of Children with Inflammatory Bowel Disease Within and Across Canadian Provinces: A Multi-Province Population-Based Cohort Study.

Purpose: The incidence of childhood-onset inflammatory bowel disease (IBD) is rising. We described variation in health services utilization and need for surgery among children with IBD between six and 60 months following IBD diagnosis across Canadian pediatric centers and evaluated the associations between care provided at diagnosis at each center and the variation in these outcomes. Patients and Methods: Using population-based deterministically-linked health administrative data from four Canadian provinces (Alberta, Manitoba, Nova Scotia, Ontario) we identified children diagnosed with IBD <16 years of age using validated algorithms. Children were assigned to a pediatric center of care using a hierarchical approach based on where they received their initial care. Outcomes included IBD-related hospitalizations, emergency department (ED) visits, and IBD-related abdominal surgery occurring between 6 and sixty months after diagnosis. Mixed-effects meta-analysis was used to pool results and examine the association between center-level care provision and outcomes. Results: We identified 3784 incident cases of pediatric IBD, of whom 2937 (77.6%) were treated at pediatric centers. Almost a third (31.4%) of children had ≥1 IBD-related hospitalization and there were 0.66 hospitalizations per person during follow-up. More than half (55.8%) of children had ≥1 ED visit and there were 1.64 ED visits per person. Between-center heterogeneity was high for both outcomes; centers where more children visited the ED at diagnosis had more IBD-related hospitalizations and more ED visits during follow-up. Between-center heterogeneity was high for intestinal resection in Crohn's disease but not colectomy in ulcerative colitis. Conclusion: There is variation in health services utilization among children with IBD and risk of undergoing intestinal resection in those with Crohn's disease, but not colectomy among children with ulcerative colitis, across Canadian pediatric tertiary-care centers. Improvements in clinical care pathways are needed to ensure all children have equitable and timely access to high quality care.

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.

Prescription ranitidine use and population exposure in 6 Canadian provinces, 1996 to 2019: a serial cross-sectional analysis.

BACKGROUND: Ranitidine was the most prescribed histamine-2 receptor antagonist (H2RA) in Canada when recalled in 2019 because of potential carcinogenicity. We sought to compare geographic and temporal patterns in use of prescription ranitidine and 3 other HRAs and estimated population exposure to ranitidine in 6 provinces between 1996 and 2019. METHODS: This population-based serial cross-sectional study used prescription claims for H2RAs dispensed from community pharmacies in Nova Scotia, Ontario, Manitoba, Saskatchewan, Alberta and British Columbia. We estimated the period prevalence of ranitidine use per 100 population by province, age category and sex. We estimated exposure to ranitidine between 2015 and 2019 using defined daily doses (DDDs). RESULTS: Overall, 2.4 million ranitidine prescriptions were dispensed to patients aged 65 years and older, and 1.7 million were dispensed to younger adults. Among older adults, the median period prevalence of ranitidine use among females was 16% (interquartile range [IQR] 13%-27%) higher than among males. Among younger adults, the median prevalence was 50% (IQR 37%-70%) higher among females. Among older adults, between 1996 and 1999, use was highest in Nova Scotia (33%) and Ontario (30%), lower in the prairies (Manitoba [18%], Saskatchewan [26%], Alberta [17%]) and lowest in BC (11%). By 2015-2019, use of ranitidine among older adults dropped by at least 50% in all provinces except BC. We estimate that at least 142 million DDDs of prescribed ranitidine were consumed annually in 6 provinces (2015-2019). INTERPRETATION: Over the 24-year period in 6 provinces, patients aged 65 years and older were dispensed 2.4 million prescriptions of ranitidine and younger adults were dispensed 1.7 million prescriptions of ranitidine. These estimates of ranitidine exposure can be used for planning studies of cancer risk and identifying target populations for cancer surveillance.

Impact of Baseline Corticosteroid Use on the Efficacy and Safety of Upadacitinib in Patients with Ulcerative Colitis: a Post Hoc Analysis of the Phase 3 Clinical Trial Programme.

BACKGROUND AND AIMS: This post hoc analysis assessed the efficacy and safety of upadacitinib in patients with moderately to severely active ulcerative colitis stratified by corticosteroid use from the ulcerative colitis Phase 3 clinical trial programme. METHODS: Patients were randomised [1:2] to 8 weeks' placebo or upadacitinib 45 mg once daily [QD]; Week 8 responders were re-randomised [1:1:1] to 52 weeks' placebo, or upadacitinib 15 or 30 mg QD. Corticosteroid dose was kept stable during induction but tapered according to a protocol-defined schedule [or investigator discretion] during maintenance Weeks 0-8. Efficacy outcomes and exposure-adjusted treatment-emergent adverse event [TEAE] rates were assessed for induction and maintenance stratified by corticosteroid use at induction baseline. RESULTS: Overall, 377/988 [38%] patients were receiving corticosteroids at induction baseline [placebo, n = 133; upadacitinib 45 mg, n = 244] and 252 [37%] of the 681 clinical responders who entered maintenance were on corticosteroids at induction baseline [n = 84 for each treatment]. Similar proportions of patients receiving upadacitinib achieved clinical remission per Adapted Mayo Score with/without corticosteroids at Weeks 8 and 52. The total proportion of patients re-initiating corticosteroids was higher with placebo [24/84 (29%)] vs UPA 15 mg [16/81 (20%)] and 30 mg [11/81 (14%)]. During induction, patients receiving corticosteroids at baseline had higher rates of TEAEs, serious TEAEs, and serious infections vs those not receiving corticosteroids; however, TEAE rates were similar during maintenance after corticosteroid withdrawal. CONCLUSIONS: Upadacitinib is an effective steroid-sparing treatment in patients with moderately to severely active ulcerative colitis.

Time for a Gut Check: A Qualitative Study of Proposed Interventions to Address Gender Inequality in Gastroenterology.

Background: Gender inequalities persist in medicine, particularly in some speciality fields where fewer women are employed. Although previous research has suggested potential interventions to broadly address gender inequality in medicine, no research has focused on interventions in the field of gastroenterology. The purpose of this research was to engage women in the field of gastroenterology in Canada, to identify interventions with potential to be effective in addressing gender inequality. Methods: A World Café was hosted in 2019 to discuss gender inequality and interventions in gastroenterology. Twelve women employed in the field of gastroenterology (i.e. physicians, nurses, research staff, and trainees) were purposively recruited and participated in the event. The discussion rounds were audio-recorded, transcribed, and thematic analyses was conducted using Braun and Clarke's principles. Results: Three key themes identifying potential interventions to address gender inequality in gastroenterology were generated: (1) Education; (2) Addressing institutional structures and polices; and 3) Role modelling and mentorship. Participants indicated that interventions should target various stakeholders, including both women and men in gastroenterology, young girls, patients, and administrators. Conclusion: Many of the interventions identified by participants correspond with existing research on interventions in general medicine, suggesting that institutional changes can be made for maximum effectiveness. Some novel interventions were also identified, including publicizing instances of gender parity and supporting interventions across the educational and professional lifecourse. Moving forward, institutions must assess their readiness for change and evaluate existing policies, programs, and practices for areas of improvement.

Perianal Fistulas Are Associated with Persistently Higher Direct Health Care Costs in Crohn's Disease: A Population-Based Study.

BACKGROUND: The economic impact of perianal fistulas in Crohn's disease (CD) has not been formally assessed in population-based studies in the biologic era. AIM: To compare direct health care costs in persons with and without perianal fistulas. METHODS: We performed a longitudinal population-based study using administrative data from Ontario, Canada. Adults (> 17 years) with CD were identified between 2007 and 2013 using validated algorithms. Perianal fistula positive "cases" were matched to up to 4 "controls" with CD without perianal fistulas based on age, sex, geographic region, year of CD diagnosis and duration of follow-up. Direct health care costs, excluding drug costs from private payers, were estimated annually beginning 5 years before (lookback) and up to 9 years after perianal fistula diagnosis (study completion) for cases and a standardized date for matched controls. RESULTS: A total of 581 cases were matched to 1902 controls. The annual per capita direct cost for cases was similar at lookback compared to controls ($2458 ± 6770 vs $2502 ± 10,752; p = 0.952), maximally greater in the first year after perianal fistulas diagnosis ($16,032 ± 21,101 vs $6646 ± 13,021; p < 0.001) and remained greater at study completion ($11,358 ± 17,151 vs $5178 ± 9792; p < 0.001). At perianal fistula diagnosis, the cost difference was driven primarily by home care cost (tenfold greater), publicly-covered prescription drugs (threefold greater) and hospitalizations (twofold greater), whereas at study completion, prescription drugs were the dominant driver (threefold greater). CONCLUSION: In our population-based cohort, perianal fistulas were associated with significantly higher direct healthcare costs at the time of perianal fistulas diagnosis and sustained long-term.