High Frequency of Undiagnosed Psychiatric Disorders in Inflammatory Bowel Diseases.

Inflammatory bowel diseases (IBD) are associated with comorbid depressive and anxiety disorders, but a significant proportion of IBD patients with psychiatric disorders (PsychD) remain undiagnosed and untreated. The aim of this study was to assess the frequency and type of undiagnosed PsychD in IBD patients. Two hundred and thirty-seven adult IBD (136 Crohn's disease (CD) and 101 ulcerative colitis (UC)) outpatients were consecutively recruited at a single university hospital centre between January 2018 and June 2019. After a scheduled follow-up visit for IBD clinical evaluation, participants underwent a semi-structured interview with a trained psychiatrist. One hundred and fourteen (48%) IBD patients had at least one PsychD, and in 67 (59%) of them, a diagnosis was made for the first time during the study. The remaining 47 (41%) patients had received a previous psychiatric diagnosis, but in only six cases was it consistent with the diagnosis made during the study. PsychD were equally distributed in CD (72/136, 53%) and UC (42/101, 42%), and mostly represented by mood disorders (54/114, 47%) and anxiety (27/114, 24%) disorders. PsychD were not related to the disease severity, phenotype or localisation of IBD, even though having three or more concomitant PsychD was associated with more severe disease in CD. Our data indicate that undiagnosed PsychD are common in IBD and highlight the importance of considering psychiatric evaluation in the management of IBD patients.