Disrupted functional connectivity of default mode and salience networks in chronic pancreatitis patients

Abstract

Objective: The functional connectivity of the brain in chronic pancreatitis (CP) remains unknown. This study aimed to investigate functional connectivity in CP patients using resting state functional magnetic resonance imaging (fMRI) and explore the associations to clinical parameters and altered cerebral metabolites.

Methods: Seed-based and ROI-to-ROI analyses were performed to assess connectivity within and between the default mode network (DMN) and salience network (SN). Additionally, functional connectivity in these networks were investigated in relation to clinical parameters (CP etiology, pain, medication, etc.) and cerebral glutamate/creatine level in the anterior cingulate cortex.

Results: Thirty CP patients and 23 healthy controls were analyzed. CP patients showed hyper-connectivity in DMN and SN as compared to healthy controls. Furthermore, CP patients had reduced anti-correlated functional connectivity between DMN and SN (all P ≤ 0.009). The altered DMN connectivity correlated to glutamate/creatine level (r = 0.503, P = 0.020) in patients with pain, but not to the clinical parameters.

Conclusions: CP patients had altered functional connectivity within and between brain networks. Altered DMN functional connectivity had an association to cerebral metabolic changes.

Significance: Altered functional connectivity in CP share similarities with other chronic pain conditions, and support our understanding of altered brain circuitry associated with the CP disease.

Keywords: Chronic pancreatitis; Chronic visceral pain; Default mode network; Functional magnetic resonance imaging; Resting state functional connectivity; Salience network.