DOP19 Incidence and initial disease presentation of inflammatory bowel diseases in Denmark: findings from a Copenhagen IBD Inception Cohort Study (IBD Prognosis Study)

Attauabi, M.(1,2)*;Madsen, G.R.(2,3);Wewer, A.V.(2,4);Bendtsen, F.(2,3);Jakobsen, C.(2,4);Dorn-Rasmussen, M.(2,4);Malham, M.(2,4);Theede, K.(2,3);Bjerrum, J.T.(1);Boysen, T.(2,3);Seidelin, J.B.(1);Burisch, J.(2,3);

(1)Copenhagen University Hospital - Herlev and Gentofte, Department of Gastroenterology and Hepatology, Herlev, Denmark;(2)Hvidovre Hospital, Copenhagen Center for Inflammatory Bowel Disease in Children- Adolescents- and Adults, Hvidovre, Denmark;(3)Copenhagen University Hospital - Amager and Hvidovre, Gastrounit- Medical Section, Hvidovre, Denmark;(4)Copenhagen University Hospital - Amager and Hvidovre, Department of Pediatrics and Adolescent Medicine, Hvidovre, Denmark;

Background

The increasing incidence of inflammatory bowel diseases (IBD), encompassing ulcerative colitis (UC), Crohn’s disease (CD), and unclassified IBD (IBD-U), in Denmark requires close surveillance. Therefore, we aimed to investigate their current incidence and initial disease presentation in a population-based inception cohort.

Methods

IBD Prognosis Study is an ongoing prospective population-based inception cohort of patients diagnosed with UC, CD, or IBD-U between May 1st, 2021, and May 1st, 2023, according to the Copenhagen IBD Criteria within the well-defined geographical uptake area of Hvidovre University Hospital and Herlev University Hospital. This area has a catchment population of 1,050,000, corresponding to ~20% of the Danish population. The incidence rate is defined as the number of new cases between May 1st, 2021, and October 31st, 2022, divided by the total number of 100,000 inhabitants covered in included sites per year during the same period. For the incidence calculations, pediatric-onset of IBD was defined as age < 19 years at diagnosis. However, for the clinical description, for the clinical presentation, the cut-off was <18 years.   

Results

As of October 31, 2022, a total of  219, 134, and 24 patients with adult-onset UC, CD, and unclassified IBD (IBD-U), respectively, has been included, corresponding to incidence rates of 13.9, 8.5, and 1.5 per 100,000 adults per year. Further, 11, 16, and two patients with pediatric-onset UC, CD, and IBD-U were included, corresponding to 3.6, 6.3, and 0.7 per 100,000 pediatric cases per year. Demographics and initial disease presentation are presented in Tables 1-2, initial disease burden and treatment patterns in Tables 3-4.












Conclusion

The preliminary data from the ongoing prospective population-based cohort, IBD Prognosis Study, indicate that the incidence rates of adult-onset IBD appear stabilized, while that of pediatric-onset CD is increasing, when compared with data from before 2010.1,2
The study is ongoing and includes extensive and continuous examinations, including endoscopy, intestinal ultrasound investigations, magnetic resonance imaging of the small intestine and biliary and pancreatic ducts, patient-reported measures, and biobanking. As such, the cohort is expected to deliver essential knowledge on the mechanisms for the unpredictable course of IBD.3

References
1.        Vind I et al. Am J Gastroenterol. 2006; doi:10.1111/j.1572-0241.2006.00552.x
2.        Jakobsen C et al. Inflamm Bowel Dis. 2011; doi:10.1002/ibd.21654
3.        Attauabi M et al. BMJ Open. 2022; doi:10.1136/bmjopen-2021-055779