Inflammatory bowel diseases are lifelong, chronic conditions affecting mostly young people. They can to some extent be treated by medication and surgery, but cannot be cured. An association between chronic inflammatory bowel disease and psychiatric disease has been suggested, which may possibly be explained by the gut-brain connection, aka ‘gut-brain-axis. This is, however, so far poorly understood. We are now able to perform detailed studies of any possible increased co-existence between chronic bowel disease and psychiatric disease. We will also be examining whether there is an increased familial clustering of the two diseases, and whether they have common genetic variants.