Hippocampal functional network: The mediating role between obsession and anxiety in adult patients with obsessive-compulsive disorder

Abstract

Objectives

Anxiety is a very common symptom and closely related to obsessive-compulsive symptoms in obsessive-compulsive disorder (OCD). However, the association between anxiety and obsessive-compulsive symptoms at the hippocampus network level remains unclear.

Methods

This study enrolled 42 patients with OCD and 42 healthy controls (HCs), who underwent resting-state functional magnetic resonance imaging (fMRI) and clinical evaluation. Multiple linear regression analysis was performed to investigate the behavioural significance and interactive effects of obsessive-compulsive and anxiety symptoms on the hippocampus functional connectivity (HFC). The mediation analysis model was used to explore whether the hippocampus functional connectivity (FC) network indirectly mediated the relationship between obsessive-compulsive symptoms and anxiety.

Results

Results showed that the FCs with the cerebellum, middle temporal gyrus (MTG) and anterior cingulate gyrus (ACG) were increased in the hippocampus FC network in patients with OCD compared with those in HCs. The regions of interactive effects between anxiety and obsession, which are mainly located in the prefrontal cortex and MTG, were positively correlated. The mediation effect is 0.018 between obsession and anxiety on the HFC networks in patients with OCD.

Conclusions

The FC between the hippocampus and MTG plays a key role in the relationship between anxiety and obsession.

Keywords:

• Obsessive-compulsive disorder
• anxiety
• obsession
• hippocampus
• functional connectivity

Acknowledgements

The authors also thank the doctors for their help in enrolling patients.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The research was supported by the NSFC-Henan mutual funds [to H-XZ, U1704190]; the National Nature Science Foundation of China [to H-XZ, No.81071091, 81571315; to M-Z, 31600927]; the Innovation Scientists and Technicians Troop Construction Projects of Henan Province [to H-XZ, No.174100510024]; the Programme for Innovative Research Team in Science and Technology in University of Henan Province [to H-XZ, N-KFKT-10, to M-Z, No.2016PN-KFKT-28]; the Open Programme of the Henan Biological psychiatry key Laboratory [to H-XZ, No.ZDSYS2014006 and to H-SZ, No. ZDSYS2015002]; and the Science and Technology Planning Project of Henan Province [to H-SZ, No. 202400410259].