The Spectrum of Psychiatric Comorbidity in Individuals With Inflammatory Bowel Disease.

Background: Research on psychiatric comorbidity in inflammatory bowel disease (IBD) has focused mostly on anxiety and depression. This study aimed to describe the spectrum of psychiatric disorders experienced by individuals with IBD and their overlap.

Methods: Participants were enrolled in a prospective 3-year longitudinal study that assessed psychiatric comorbidity in immune-mediated inflammatory disease. Lifetime prevalence of psychiatric comorbidity was assessed using the Structured Clinical Interview for DSM-IV Disorders (SCID-IV), as the DSM-IV was the prevailing classification at the time of study design. Diagnosis was aligned with DSM-5 categorization where possible with available data. Psychiatric burden was categorized as no psychiatric conditions, 1, 2 or 3 or more psychiatric conditions.

Results: Of 154 IBD participants (62%female, 63% Crohn's disease) 57% had at least one psychiatric comorbidity with 27% having >1 psychiatric diagnosis. The prevalence was major depressive disorder (MDD, 41.7%), anxiety disorders (39.6%; grouped as per DSM-5), substance use disorder (SUD, 16.2%), posttraumatic stress disorder (5.3%), obsessive-compulsive disorder (4.9%), and bipolar disorder (2.0%). Of participants with MDD and a comorbid psychiatric disorder, nearly half had SUD. Of those with >1 psychiatric disorder >70% had MDD and a comorbid anxiety disorder. Persons with ≥1 psychiatric comorbidity were more likely to be current smokers (P < .001) and to have higher IBD disease activity scores (P = .005) than those without a psychiatric comorbidity.

Conclusions: Over half of adults with IBD had >1 diagnosed psychiatric comorbidity from a range of 10 different psychiatric disorders identified. Further research should assess the temporal relationship of IBD and the various psychiatric presentations to better understand the trajectory of co-occurrence, and therapy which may concurrently address the psychiatric disorder and the IBD.