title: Cerebral blood flow autoregulation is impaired in schizophrenia: A pilot study.
abstract: Patients with schizophrenia have a higher risk of cardiovascular diseases and higher mortality from them than does the general population; however, the underlying mechanism remains unclear. Impaired cerebral autoregulation is associated with cerebrovascular diseases and their mortality. Increased or decreased cerebral blood flow in different brain regions has been reported in patients with schizophrenia, which implies impaired cerebral autoregulation. This study investigated the cerebral autoregulation in 21 patients with schizophrenia and 23 age- and sex-matched healthy controls. None of the participants had a history of cardiovascular diseases, hypertension, or diabetes. All participants underwent 10-min blood pressure and cerebral blood flow recording through finger plethysmography and Doppler ultrasonography, respectively. Cerebral autoregulation was assessed by analyzing two autoregulation indices: the mean blood pressure and cerebral blood flow correlation coefficient (Mx), and the phase shift between the waveforms of blood pressure and cerebral blood flow determined using transfer function analysis. Compared with the controls, the patients had a significantly higher Mx (0.257 vs. 0.399, p=0.036) and lower phase shift (44.3° vs. 38.7° in the 0.07-0.20Hz frequency band, p=0.019), which indicated impaired maintenance of constant cerebral blood flow and a delayed cerebrovascular autoregulatory response. Impaired cerebral autoregulation may be caused by schizophrenia and may not be an artifact of coexisting medical conditions. The mechanism underlying impaired cerebral autoregulation in schizophrenia and its probable role in the development of cerebrovascular diseases require further investigation.
authors.affiliation: Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Brain and Consciousness Research Center, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan.
authors.forename: Hsiao-Lun
authors.initials: HL
authors.lastname: Ku
authors.affiliation: Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Brain and Consciousness Research Center, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan.
authors.forename: Jiunn-Kae
authors.initials: JK
authors.lastname: Wang
authors.affiliation: Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Research Center of Sleep Medicine, College of Medicine, Taipei, Taiwan.
authors.forename: Hsin-Chien
authors.initials: HC
authors.lastname: Lee
authors.affiliation: Brain and Consciousness Research Center, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Graduate Institute of Humanities in Medicine, College of Humanities and Social Sciences, Taipei Medical University, Taipei, Taiwan; Institute of European and American Studies, Academia Sinica, Taipei, Taiwan; Research Center for Mind, Brain and Learning, National Chengchi University, Taipei, Taiwan.
authors.forename: Timothy Joseph
authors.initials: TJ
authors.lastname: Lane
authors.affiliation: Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: I-Chao
authors.initials: IC
authors.lastname: Liu
authors.affiliation: Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan.
authors.forename: Yung-Chan
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan.
authors.forename: Yao-Tung
authors.initials: YT
authors.lastname: Lee
authors.affiliation: Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan.
authors.forename: I-Cheng
authors.initials: IC
authors.lastname: Lin
authors.affiliation: Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan.
authors.forename: Chia-Pei
authors.initials: CP
authors.lastname: Lin
authors.affiliation: Department of Neurology, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Neurology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Cerebrovascular Research Center, Taipei Medical University, Taipei, Taiwan.
authors.forename: Chaur-Jong
authors.initials: CJ
authors.lastname: Hu
authors.affiliation: Department of Neurology, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Neurology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Cerebrovascular Research Center, Taipei Medical University, Taipei, Taiwan. Electronic address: naifangchi@tmu.edu.tw.
authors.forename: Nai-Fang
authors.initials: NF
authors.lastname: Chi
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D001795:Blood Pressure Determination; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology; D002561:Cerebrovascular Disorders / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D005385:Fingers / Q000098:blood supply / Q000503:physiopathology; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D010991:Plethysmography; D012559:Schizophrenia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D017585:Ultrasonography, Doppler, Transcranial
keywords: Cerebral autoregulation; Cerebral blood flow; Cerebrovascular diseases; Schizophrenia