title: Sleep electroencephalographic spectral power after withdrawal from alcohol in alcohol-dependent patients.
abstract: BACKGROUND
  Dysfunctional hyperarousal is suspected to be a neurophysiological determinant of relapse in abstinent alcohol-dependent patients. In the present study, we used spectral power analysis of the sleep electroencephalographic (EEG) to quantify brain activity during sleep in patients during subacute withdrawal as well as in control subjects. Our hypothesis was that the subgroup of patients who relapsed within the 3 months to follow-up would exhibit-increased dysfunctional arousal manifested by higher-frequency (beta) EEG power during sleep.
  
  
  METHODS
  Twenty-six alcohol-dependent in-patients were examined with polysomnography over 2 nights 2 to 3 weeks after withdrawal. At the 3-month clinical follow-up assessment, 12 of them had relapsed and 14 abstained. The control group consisted of 23 healthy subjects similar to the patients with alcohol dependence in age and gender distribution. Spectral sleep EEG analysis was performed on both nights (adaptation and baseline) of all subjects. Logarithmic artifact-controlled spectral band power of sleep stage 2 and rapid eye movement (REM) sleep was analyzed for Group, Gender, and Age effects using multiple analyses of covariance. Three groups were compared with the Group factor: relapsers, abstainers, and controls.
  
  
  RESULTS
  Generally, both Group and Age effects were significant for the second, baseline night for the visually scored sleep parameters, while spectral EEG parameters showed significant differences in the adaptation night. In the adaptation night, a significant enhancement in the beta2 band (24-32 Hz) was seen in REM sleep in relapsers relative to both abstainers and controls.
  
  
  CONCLUSIONS
  The beta2 increase could be interpreted as a sign of dysfunctional arousal during REM sleep "unmasked" by the additional stressor of sleep environment adaptation. Its determinants are likely to be both premorbid and drinking history related.
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Freiburg, Hauptstrasse 5, Freiburg 79104, Germany. Bernd.Feige@gmx.net
authors.forename: Bernd
authors.initials: B
authors.lastname: Feige
authors.forename: Susanne
authors.initials: S
authors.lastname: Scaal
authors.forename: Magdolna
authors.initials: M
authors.lastname: Hornyak
authors.forename: Horst
authors.initials: H
authors.lastname: Gann
authors.forename: Dieter
authors.initials: D
authors.lastname: Riemann
mesh_terms: D000328:Adult; D000375:Aging / Q000502:physiology / Q000523:psychology; D000437:Alcoholism / Q000503:physiopathology* / Q000523:psychology; D015992:Body Mass Index; D002492:Central Nervous System Depressants / Q000009:adverse effects*; D003863:Depression / Q000523:psychology; D004569:Electroencephalography; D004576:Electromyography; D000431:Ethanol / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D017286:Polysomnography; D011569:Psychiatric Status Rating Scales; D012727:Sex Characteristics; D012890:Sleep / Q000502:physiology*; D012895:Sleep, REM / Q000502:physiology; D013375:Substance Withdrawal Syndrome / Q000503:physiopathology* / Q000523:psychology
chemical_list: D002492:Central Nervous System Depressants; D000431:Ethanol