Background
Recent studies have shown that the brain of patients with gastrointestinal disease differ both structurally and functionally from that of controls. Highly somatizing diverticular disease (HSDD) patients were also shown to differ from low somatizing (LSDD) patients functional-ly. This study aimed to investigate how they differed structurally.
Methods
Four diseases subgroups were studied in a cross-sectional design: 20 patients with asympto-matic diverticular disease (ADD), 18 LSDD, 16 HSDD, and 18 with irritable bowel syn-drome. We divided DD patients into LSDD and HSDD using a cutoff of 6 on the Patient Health Questionnaire 12 Somatic Symptom (PHQ12-SS) scale. All patients underwent a 1-mm isotropic structural brain MRI scan and were assessed for somatization, hospital anxiety, depression, and pain catastrophizing. Whole brain volumetry, cortical thickness analysis and voxel-based morphometry were carried out using Freesurfer and SPM.
Key Results
We observed decreases in grey matter density in the left and right dorso-lateral prefrontal cortex (dlPFC), and in the mid-cingulate and motor cortex, and increases in the left (19, 20) and right (19, 38) Brodmann Areas. The average cortical thickness differed overall across groups (P=0.002) and regionally: HSDD>ADD in the posterior cingulate cortex (P=0.03), HSDD>LSDD in the dlPFC (P=0.03) and in the ventro-lateral PFC (P<0.001). The thickness of the anterior cingulate cortex and of the mid-prefrontal cortex were also found to correlate with Pain Catastrophizing (Spearman's ρ=0.24, P=0.043 uncorrected and Spearman's ρ=0.25, P=0.03 uncorrected).
Conclusion & Inferences
This is the first study of structural grey matter abnormalities in diverticular disease patients. The data shows brain differences in the pain network
