title: Etiology, neurologic correlations, and prognosis in alpha coma.
abstract: OBJECTIVE
  To determine the factors affecting prognosis in alpha coma (AC).
  
  
  METHODS
  Retrospective review of 36 study patients, 36 control coma patients matched for age and etiology, and meta-analysis of 335 cases in the world literature.
  
  
  RESULTS
  Principal causes were cardiorespiratory arrest (CRA) (21 patients); infection, metabolic dysfunction, head trauma (3 each); and drugs, stroke and hypoxia (2 each). Outcome was predicated by EEG reactivity to noxious stimuli. Fourteen of the 15 patients with reactive EEGs, had measurable outcome, 8 awoke - all but two had etiologies other than CRA. Fourteen of 19 patients without EEG reactivity died; two had support discontinued and 3 awoke. Following CRA, 16/21 patients died and 3 had support discontinued. Only 3 patients made a good recovery - all with toxic or metabolic etiologies. Literature meta-analysis of 335 cases showed that overall, AC carried a poor prognosis (76% died). CRA (226 cases) had an 88% mortality; strokes (29 cases), a 90% mortality; hypoxia without cardiac arrest (28 cases), a 61% mortality; drug-induced AC (25 cases), an 8% mortality.
  
  
  CONCLUSIONS
  Although the cause of AC largely predicts outcome, EEG reactivity in AC predicted survival: most patients with reactivity awoke; most of those without, died. Few survivors had meaningful recovery.
authors: Johns Hopkins Bayview Medical Center, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
authors: P W
authors: PW
authors: Kaplan
authors: D
authors: D
authors: Genoud
authors: T W
authors: TW
authors: Ho
authors: P
authors: P
authors: Jallon
mesh_terms: D000328:Adult; D000368:Aged; D000513:Alpha Rhythm; D003128:Coma / Q000209:etiology / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis