Central Nervous System Mechanisms of Nausea in Gastroparesis: An fMRI-Based Case–Control Study
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Nausea is a major complaint of gastroparesis (GP), and the pathophysiology of this condition is poorly understood. Therefore, this study utilized fMRI to investigate the possible central nervous system (CNS) mechanisms of nausea in 10 GP patients versus 8 healthy controls (HCs).
Nausea severity was assessed on a 0–10 scale and presented as mean ± SD. Nausea was increased from baseline utilizing up to 30 min of visual stimulation (VS). Functional network connectivity was measured with fMRI at baseline and after 30 min of VS. fMRI data were preprocessed using statistical parametric mapping software. Thirty-four independent components were identified as meaningful resting-state networks (RSNs) by group independent component analysis. The Functional Network Connectivity (FNC) among 5 RSNs considered important in CNS nausea mechanisms was calculated as the Pearson’s pairwise correlation.
Baseline nausea score in GP patients was 2.7 ± 2.0 and increased to 7.0 ± 1.5 after stimulation (P < 0.01). In HCs nausea scores did not increase from baseline after stimulus (0.3 ± 0.5). When comparing GP patients to HCs after VS, a significant reduction (P < 0.001) in bilateral insula network connectivity compared to the right insula network was detected. No significant differences in connectivity were noted among the other RSNs. Additionally, the average gray matter volume was non-significantly reduced in the insula in GP patients compared to HC.
The insula connectivity network is impaired in nauseated GP patients. This phenomenon could explain the susceptibility of GP patients to nausea or may have resulted from a state of chronic nausea.
KeywordsCentral nervous system fMRI Functional network connectivity Gastroparesis Nausea
Functional magnetic resonance imaging
Functional network connectivity
Group independent component analysis
The funding for this work was provided by Texas Tech University Health Sciences Center of El Paso Internal Medicine Department Seed Grant and Texas Tech University Health Sciences Center of El Paso, Paul L. Foster School of Medicine Scholarly Activity and Research Program Mini Grant.
Compliance with Ethical Standards
Conflict of interest
Dr. Richard McCallum was supported by CinRx Pharma (Consultant or advisor), GI Stimultation-Patent on “gastric pacing” (owner of patent), Allergan Pharma, Takeda Pharma, Vanda Pharma, (Research Support), Salix Pharma (Speaker’s Bureau, Takeda Pharma (Publications, Steering Committee). The other authors declare that they have no conflict of interest.
- 12.Allen EA, Erhardt EB, Damaraju E, et al. A baseline for the multivariate comparison of resting-state networks. Frontiers Syst Neurosci. 2011;5:2.Google Scholar
- 16.Cordes D, Haughton VM, Arfanakis K, et al. Frequencies contributing to functional connectivity in the cerebral cortex in “resting-state” data. AJNR Am J Neuroradiol. 2001;22:1326–1333.Google Scholar