Inflammatory bowel disease may be a causal risk factor for psoriasis and psoriatic arthritis, increasing the risk of the conditions by 10%, a large genomics study shows.

The first-of-its-kind study did not, however, demonstrate any association in the reverse direction.

German researchers hope the new finding will encourage clinicians to systematically assess patients — ultimately leading to improved management and outcomes.

The University Hospital of Ausburg–led team also showed that the unidirectional causal relationship between the two immune-mediated conditions appeared to be driven by Crohn’s disease rather than ulcerative colitis.