Clinnova-IBD, a Prospective Cohort of Patients With Inflammatory Bowel Disease (IBD)

Inclusion Criteria: * ≥ 18 years old * Participants are willing and able to comply with the protocol including undergoing data and sample collection as well as study visits and examinations. * Signed informed consent form * Diagnosed with Inflammatory bowel disease, either Crohn's disease or ulcerative colitis, at least 3 months before the enrolment AND occurrence of a significant change in the treatment of the disease (either change of drug dosage OR change of medication within the same treatment class OR change of treatment class OR addition of a drug to a treatment regimen already ongoing). A change of drug dosage or frequency is considered significant if it fulfills the requirements in section 7.1 Note: Patients with ostomy or with short bowel syndrome can be included if they fulfill all the eligibility criteria Exclusion Criteria: * Any condition that could potentially hamper the compliance with the study protocol, including study procedures and study visits (such as mental disability that makes it difficult or impossible to answer questionnaires) * Not fluent in any of the following languages: French, English or German * Known pregnancy