title: Delirium in acute subarachnoid haemorrhage.
abstract: BACKGROUND
  Delirium may be a presenting feature in acute subarachnoid haemorrhage (SAH). The aim of this study was to investigate the risk factors for delirium in acute SAH and to analyse the relation between delirium and location and amount of haematic densities and hydrocephalus.
  
  
  METHODS
  We assessed delirium in a sample of 68 consecutive patients with acute (< or =4 days) SAH (33 aneurysmal, 33 non-aneurysmal, including 9 with perimesencephalic haemorrhage), before aneurysmal treatment, using DSM-IV-R criteria and the Delirium Rating Scale (DRS). DRS scores were related to: (1) the total amount of haematic densities at 10 basal cisterns/fissures and in the 4 ventricles, using a validated rating scale, (2) the haematic densities in the prepontine cistern and the convexity of the brain and (3) hydrocephalus, using the bicaudate index, obtained from a review of admission CT scans.
  
  
  RESULTS
  Eleven acute SAH patients presented with delirium. Older age (U = 316.5, p = 0.04), alertness disturbance (chi(2) = 5.1, p = 0.02, OR = 7.6, 95% CI = 1.5-37.3), aphasia (U = 61.5, p = 0.007) and a Hunt and Hess score >2 (U = 362.5, p = 0.02) were associated with delirium. Higher amounts of intraventricular haematic densities (chi(2) = 4.43, p = 0.04, U = 158, p = 0.001) and hydrocephalus (U = 215, p = 0.009) were also associated with higher DRS scores. Two delirious patients had basofrontal haematomas.
  
  
  CONCLUSIONS
  Delirium was detected in 16% of acute SAH patients. Intraventricular bleeding, hydrocephalus and basofrontal haematomas contribute to the pathogenesis of delirium, through damage to anatomical networks subserving sustained attention, declarative memory and the expression of emotional behaviour.
authors.affiliation: Stroke Unit, Department of Neurosciences and Mental Health, Serviço de Neurologia, Hospital de Santa Maria, PT-1649-035 Lisboa, Portugal. jmferro@fm.ul.pt
authors.forename: Lara
authors.initials: L
authors.lastname: Caeiro
authors.forename: Coraline
authors.initials: C
authors.lastname: Menger
authors.forename: José M
authors.initials: JM
authors.lastname: Ferro
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Albuquerque
authors.forename: M Luísa
authors.initials: ML
authors.lastname: Figueira
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003693:Delirium / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000209:etiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012720:Severity of Illness Index; D013345:Subarachnoid Hemorrhage / Q000150:complications* / Q000453:epidemiology*