title: Longitudinal brain structural alterations and systemic inflammation in obstructive sleep apnea before and after surgical treatment.
abstract: Systemic inflammation, neurocognitive impairments, and morphologic brain changes are associated with obstructive sleep apnea (OSA). Understanding their longitudinal evolution and interactions after surgical treatment provides clues to the pathogenesis of cognitive impairment and its reversibility. In the present study, we investigate clinical disease severity, systemic inflammation, cognitive deficits, and corresponding gray matter volume (GMV) changes in OSA, and the modifications following surgery.
  
  
  
  Twenty-one patients with OSA (apnea-hypopnea index, AHI > 5) and 15 healthy volunteers (AHI < 5) underwent serial evaluation, including polysomnography, flow cytometry for leukocyte apoptosis categorization, cognitive function evaluation, and high-resolution brain scan. Disease severity, leukocyte apoptosis, cognitive function, and imaging data were collected to assess therapeutic efficacy 3 months after surgery.
  
  
  
  Pre-operatively, patients presented with worse cognitive function, worse polysomnography scores, and higher early leukocyte apoptosis associated with increased insular GMV. There was reduced GMV in the anterior cingulate gyrus before and after surgery in the cases compared to that in controls, suggesting an irreversible structural deficit. Post-operatively, there were significant improvements in different cognitive domains, including attention, executive and visuospatial function, and depression, and in early leukocyte apoptosis. There was also a significant decrease in GMVs after treatment, suggesting recovery from vasogenic edema in the precuneus, insula, and cerebellum. Improvement in early leukocyte apoptosis post-surgery predicted better recovery of precuneus GMV.
  
  
  
  In OSA, increased disease severity and systemic inflammation can alter GMV in vulnerable regions. Surgical treatment may improve disease severity and systemic inflammation, with subsequent recovery in brain structures and functions.
authors.affiliation: Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Wei-Che
authors.initials: WC
authors.lastname: Lin
authors.affiliation: Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Huang
authors.affiliation: Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan.|Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Hsiu-Ling
authors.initials: HL
authors.lastname: Chen
authors.affiliation: Department of Brain Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Kun-Hsien
authors.initials: KH
authors.lastname: Chou
authors.affiliation: Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Pei-Chin
authors.initials: PC
authors.lastname: Chen
authors.affiliation: Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Nai-Wen
authors.initials: NW
authors.lastname: Tsai
authors.affiliation: Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Meng-Hsiang
authors.initials: MH
authors.lastname: Chen
authors.affiliation: Division of Sleep Surgery, Department of Otolaryngology-Head and Neck Surgery, Rush University Medical Center, Chicago, IL, USA.|Department of Otolaryngology, Advanced Center for Specialty Care, Advocate Illinois Masonic Medical Center, Chicago, IL, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Friedman
authors.affiliation: Department of Otolaryngology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 123, Ta Pei Road, Niao Sung District, Kaohsiung, Taiwan. hclin@cgmh.org.tw.|Sleep Center, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan. hclin@cgmh.org.tw.
authors.forename: Hsin-Ching
authors.initials: HC
authors.lastname: Lin
authors.affiliation: Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan. chlu99@ms44.url.com.|Department of Biological Science, National Sun Yat-Sen University, Kaohsiung, Taiwan. chlu99@ms44.url.com.
authors.forename: Cheng-Hsien
authors.initials: CH
authors.lastname: Lu
mesh_terms: D000328:Adult; D017209:Apoptosis; D001921:Brain / Q000473:pathology* / Q000601:surgery*; D016022:Case-Control Studies; D003071:Cognition; D003710:Demography; D005260:Female; D066128:Gray Matter / Q000473:pathology; D006801:Humans; D007249:Inflammation / Q000150:complications* / Q000473:pathology*; D007962:Leukocytes / Q000473:pathology; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000503:physiopathology / Q000601:surgery*
keywords: Leukocyte apoptosis; Magnetic resonance imaging; Obstructive sleep apnea; Oxidative stress; Voxel-based morphometry