P099 Altered intrinsic brain function in Crohn's disease
Thomann A.*1, Griebe M.2, Thomann P.3, Reindl W.4, Wolf C.3
1Universitätsmedizin Mannheim, Department of Medicine II, Mannheim, Germany 2Universitätsmedizin Mannheim, Department of Neurology, Mannheim, Germany 3Universitätsklinik Heidelberg, Department of Psychiatry, Heidelberg, Germany 4Universitätsmedizin Mannheim, Department of Medicine II, Mannheim, Germany
Psychological factors play an important role in inflammatory bowel diseases (IBD), where comorbidity of mental disorders shows a higher prevalence than in the general population. As suggested by previous neuroimaging studies, such comorbidity could be associated with a specific neural phenotype. Brain regions associated with emotion regulation and self-referential processing, including areas assigned to the so-called “default mode network” (DMN), could be promising candidates in this regard. Here, we investigated the functional integrity of multiple intrinsic neural networks in remitted patients with Crohn's disease (CD). We also sought to establish relationships between neural network connectivity and psychiatric symptoms, such as anxiety and depression.
Resting-state functional magnetic resonance imaging at 3 Tesla was conducted in 15 CD patients in stable remission and 14 healthy controls (HC). All participants underwent testing for cognition, depression and anxiety. An Independent Component Analysis was computed to identify spatiotemporally distinct intrinsic neural networks. From a total of 27 estimated independent components, 4 networks of interest (anterior and posterior DMN [aDMN, pDMN] as well as left and right lateralized frontoparietal networks) were chosen for further analyses. Between-network functional connectivity was investigated using a constrained maximal lag correlation approach.
The groups did not differ in cognition, depression or anxiety scores. Abnormal connectivity in CD patients was observed in the aDMN and pDMN. Increased connectivity in CD was found in the anterior cingulate and left superior medial frontal gyrus (aDMN) and the middle cingulate cortex (pDMN). Middle cingulate activity significantly correlated with anxiety scores in patients (r=0.562, p=0.029). Between-network coupling did not significantly differ between the groups.
This study provides first evidence of selectively disrupted intrinsic neural network connectivity in remitted CD patients. The data suggest abnormalities of self-referential neural networks, in contrast to systems predominantly related to extrinsic processing. An increased sensitivity to self-related affective and somatic states in CD patients could account for these findings and explain a higher risk for anxiety symptoms.