Hormone Levels Are Associated with Altered Brain Structure and Functional Connectivity in Prolactinomas (2301)

Objective: By employing the functional magnetic resonance imaging technique, we aimed to investigate the brain structure alteration and whole-brain functional connectivity (FC) patterns and their association with endogenous hormone levels in patients with a prolactinoma. Background: Prolactinomas may cause drastic hormone fluctuations throughout the body. It is not fully understood how endogenous hormone disorders such as prolactinomas reshape the patient’s brain. Design/Methods: Using voxel-based morphometry analysis and seed-based correlation analysis across whole brain, we compared gray matter volume (GMV) and FC metrics between 33 prolactinoma patients and 31 healthy controls matched with age, sex, and handedness. Partial correlation analysis and multiple linear regression were performed to determine the relationship between hormone levels and GMV and FC. Results: Compared to healthy controls, we found that prolactinoma patients demonstrated GMV decrease in the left hippocampus, left orbitofrontal cortex, right middle frontal cortex (MFC), and right inferior frontal cortex (IFC). Patients also showed significantly increased thalamocortical (visual cortex) and cerebellar-cerebral connectivity. Furthermore, in prolactinomas, we found a negative relationship between serum prolactin levels and the GMV of the left hippocampus and right IFC, whereas a positive relationship was found between the GMV of the left hippocampus and serum levels of estradiol and luteinizing hormone, respectively. Also, hormone levels were positively correlated with the increased FC, and such hormone-FC relationships were sex-dependent in prolactinoma patients. Conclusions: Our findings are the first to reveal the altered GMV and FC patterns, and their association with hormone levels in prolactinoma patients, indicating the important role of hormone levels in brain structure changes and hyperactive intrinsic connections in prolactinomas. Disclosure: Dr. YAO has nothing to disclose. Dr. Chen has nothing to disclose. Dr. Wang has nothing to disclose.