title: Differential spectral quantitative electroencephalography patterns between control and Parkinson's disease cohorts.
abstract: OBJECTIVE
  It is believed that progressive Lewy-type synucleinopathy (LTS) is primarily responsible for the worsening of motor and non-motor Parkinson's disease (PD) signs and symptoms. Characterization of quantitative electroencephalography (QEEG) abnormalities across the spectrum of LTS to PD dementia (PD-D) may provide insight into the pathophysiology of PD cortical dysfunction. Here our enlarged EEG database was leveraged to characterize spectral QEEG abnormalities in asymptomatic autopsy-defined groups of control participants and incidental Lewy body disease (ILBD) and three clinically defined groups of participants with PD (cognitively normal PD, mild cognitive impairment PD, and PD-D).
  
  
  METHODS
  The PD cohort was studied as part of the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). AZSAND utilizes its Brain and Body Donation Program to perform prospective, standardized, regular longitudinal pre-mortem assessments until death. Resting EEG from subjects was analyzed for spectral domain QEEG measures of background rhythm frequency and global relative power in delta, theta, alpha and beta bands.
  
  
  RESULTS
  The various spectral QEEG measures showed differential changes specific to the groups compared. Important findings were background rhythm frequency showing the most pairwise differences across the groups, and this also was the only significant difference between control and ILBD. An increase in delta bandpower was characteristic of worsening cognitive deficits.
  
  
  CONCLUSIONS
  Different patterns of change amongst QEEG measures across LTS and PD cognitive states suggest that they correlate with heterogeneous pathophysiologies of cortical dysfunction within the PD clinical spectrum. In addition, the biomarker application of a specific spectral QEEG measure needs to be selectively suited to its study purpose.
authors.affiliation: Department of Neurology, Mayo Clinic, Scottsdale, AZ, USA.
authors.forename: J N
authors.initials: JN
authors.lastname: Caviness
authors.affiliation: Department of Neurology, Mayo Clinic, Scottsdale, AZ, USA.
authors.forename: R L
authors.initials: RL
authors.lastname: Utianski
authors.affiliation: Department of Neurology, Mayo Clinic, Scottsdale, AZ, USA.
authors.forename: J G
authors.initials: JG
authors.lastname: Hentz
authors.affiliation: Banner Sun Health Research Institute, Sun City, AZ, USA.
authors.forename: T G
authors.initials: TG
authors.lastname: Beach
authors.affiliation: Banner Sun Health Research Institute, Sun City, AZ, USA.
authors.forename: B N
authors.initials: BN
authors.lastname: Dugger
authors.affiliation: Banner Sun Health Research Institute, Sun City, AZ, USA.
authors.forename: H A
authors.initials: HA
authors.lastname: Shill
authors.affiliation: Department of Neurology, Mayo Clinic, Scottsdale, AZ, USA.
authors.forename: E D
authors.initials: ED
authors.lastname: Driver-Dunckley
authors.affiliation: Banner Sun Health Research Institute, Sun City, AZ, USA.
authors.forename: M N
authors.initials: MN
authors.lastname: Sabbagh
authors.affiliation: Department of Neurology, Mayo Clinic, Scottsdale, AZ, USA.
authors.forename: S
authors.initials: S
authors.lastname: Mehta
authors.affiliation: Department of Neurology, Mayo Clinic, Scottsdale, AZ, USA.
authors.forename: C H
authors.initials: CH
authors.lastname: Adler
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers; D001921:Brain / Q000503:physiopathology*; D003937:Diagnosis, Differential; D004569:Electroencephalography / Q000379:methods*; D005260:Female; D006801:Humans; D020961:Lewy Body Disease / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology*
chemical_list: D015415:Biomarkers
keywords: EEG; Parkinson's disease; biomarker; dementia; pathology; synucleinopathy