Irritable bowel syndrome in female patients is associated with alterations in structural brain networks.
Alterations in gray matter (GM) density/volume and cortical thickness (CT) have been demonstrated in small and heterogeneous samples of subjects with differing chronic pain syndromes, including irritable bowel syndrome (IBS). Aggregating across 7 structural neuroimaging studies conducted at University of California, Los Angeles, Los Angeles, CA, USA, between August 2006 and April 2011, we examined group differences in regional GM volume in 201 predominantly premenopausal female subjects (82 IBS, mean age: 32±10 SD, 119 healthy controls [HCs], 30±10 SD). Applying graph theoretical methods and controlling for total brain volume, global and regional properties of large-scale structural brain networks were compared between the group with IBS and the HC group. Relative to HCs, the IBS group had lower volumes in the bilateral superior frontal gyrus, bilateral insula, bilateral amygdala, bilateral hippocampus, bilateral middle orbital frontal gyrus, left cingulate, left gyrus rectus, brainstem, and left putamen. Higher volume was found in the left postcentral gyrus. Group differences were no longer significant for most regions when controlling for the Early Trauma Inventory global score, with the exception of the right amygdala and the left postcentral gyrus. No group differences were found for measures of global and local network organization. Compared to HCs, in patients with IBS, the right cingulate gyrus and right thalamus were identified as being significantly more critical for information flow. Regions involved in endogenous pain modulation and central sensory amplification were identified as network hubs in IBS. Overall, evidence for central alterations in patients with IBS was found in the form of regional GM volume differences and altered global and regional properties of brain volumetric networks.
Oppenheimer Family Center for Neurobiology of Stress, Pain and Interoception Network (PAIN), David Geffen School of Medicine at UCLA, Los Angeles, CA, USA Laboratory of Neuro Imaging (LONI), Department of Neurology, University of California, Los Angeles, Los Angeles, CA, USA Ahmanson-Lovelace Brain Mapping Center, University of California, Los Angeles, Los Angeles, CA, USA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA.
Jennifer S
JS
Labus
Ivo D
ID
Dinov
Zhiguo
Z
Jiang
Cody
C
Ashe-McNalley
Alen
A
Zamanyan
Yonggang
Y
Shi
Jui-Yang
JY
Hong
Arpana
A
Gupta
Kirsten
K
Tillisch
Bahar
B
Ebrat
Sam
S
Hobel
Boris A
BA
Gutman
Shantanu
S
Joshi
Paul M
PM
Thompson
Arthur W
AW
Toga
Emeran A
EA
Mayer
D000328:Adult; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D043183:Irritable Bowel Syndrome / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D009434:Neural Pathways / Q000473:pathology*; D012189:Retrospective Studies; D055815:Young Adult
Brain network analysis; Chronic pain; Graph theory; Gray matter volume; Irritable bowel syndrome