title: Abnormal Intrinsic Functional Hubs in Severe Male Obstructive Sleep Apnea: Evidence from a Voxel-Wise Degree Centrality Analysis.
abstract: OBJECTIVE
  Obstructive sleep apnea (OSA) has been associated with changes in brain structure and regional function in certain brain areas. However, the functional features of network organization in the whole brain remain largely uncertain. The purpose of this study was to identify the OSA-related spatial centrality distribution of the whole brain functional network and to investigate the potential altered intrinsic functional hubs.
  
  
  METHODS
  Forty male patients with newly confirmed severe OSA on polysomnography, and well-matched good sleepers, participated in this study. All participants underwent a resting-state functional MRI scan and clinical and cognitive evaluation. Voxel-wise degree centrality (DC) was measured across the whole brain, and group difference in DC was compared. The relationship between the abnormal DC value and clinical variables was assessed using a linear correlation analysis.
  
  
  RESULTS
  Remarkably similar spatial distributions of the functional hubs (high DC) were found in both groups. However, OSA patients exhibited a pattern of significantly reduced regional DC in the left middle occipital gyrus, posterior cingulate cortex, left superior frontal gyrus, and bilateral inferior parietal lobule, and DC was increased in the right orbital frontal cortex, bilateral cerebellum posterior lobes, and bilateral lentiform nucleus, including the putamen, extending to the hippocampus, and the inferior temporal gyrus, which overlapped with the functional hubs. Furthermore, a linear correlation analysis revealed that the DC value in the posterior cingulate cortex and left superior frontal gyrus were positively correlated with Montreal cognitive assessment scores, The DC value in the left middle occipital gyrus and bilateral inferior parietal lobule were negatively correlated with apnea-hypopnea index and arousal index in OSA patients.
  
  
  CONCLUSIONS
  Our findings suggest that OSA patients exhibited specific abnormal intrinsic functional hubs including relatively reduced and increased DC. This expands our understanding of the functional characteristics of OSA, which may provide new insights into understanding the dysfunction and pathophysiology of OSA patients.
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Haijun
authors.identifier: http://orcid.org/0000-0001-6631-123X
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.|School of Public Health, Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Ophthalmology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Shao
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Honghan
authors.initials: H
authors.lastname: Gong
authors.affiliation: Department of Pneumology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Xianjun
authors.initials: X
authors.lastname: Zeng
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Chenglong
authors.initials: C
authors.lastname: Ye
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Si
authors.initials: S
authors.lastname: Nie
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Liting
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China.
authors.forename: Dechang
authors.initials: D
authors.lastname: Peng
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000000981:diagnostic imaging / Q000503:physiopathology; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000000981:diagnostic imaging / Q000503:physiopathology