title: Comparison of postoperative cognitive function in patients undergoing surgery for ruptured and unruptured intracranial aneurysm.
abstract: BACKGROUND
  Patients with SAH often experience cognitive decline. Previous studies used normal volunteers, published normal test values, and orthopedic patients as controls to identify factors for postoperative cognitive decline. The present study excluded the effects of surgery by comparing cognitive function after surgical repair in patients with aneurysmal SAH and patients with unruptured intracranial aneurysm.
  
  
  METHODS
  This study recruited 117 patients with SAH due to ruptured aneurysm and 39 patients with incidentally found unruptured intracranial aneurysms. The cognitive test battery consisted of the Japanese translation of the WAIS-R, the Japanese translation of the WMS, and the recall trial of the ROCF. Postoperative neuropsychological test scores for the patients with SAH and control subjects were compared using group-rate and event-rate analysis. The relationship between clinical variable and postoperative cognitive decline in the patients with SAH was evaluated by univariate analysis using the Mann-Whitney U test or chi(2) test.
  
  
  RESULTS
  Group-rate analysis showed that the WAIS-R and ROCF scores were significantly lower in the SAH group than in the control group. Event-rate analysis demonstrated that the incidence of cognitive decline in the patients with SAH (73 [62.4%] of the 117 patients) was significantly higher than that in the control subjects (12 [30.8%] of 39 patients). The Hunt and Hess grade was significantly higher in patients with postoperative cognitive decline.
  
  
  CONCLUSIONS
  The cognitive function after SAH was significantly correlated with Hunt and Hess grade on admission when using patients with postoperative unruptured intracranial aneurysm as the control group.
authors.affiliation: Department of Neurosurgery, Iwate Medical University, Morioka, Iwate 020-8505, Japan. ootawara-nsu@umin.ac.jp
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Otawara
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Ogasawara
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Kubo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kashimura
authors.forename: Akira
authors.initials: A
authors.lastname: Ogawa
authors.forename: Keiko
authors.initials: K
authors.lastname: Yamadate
mesh_terms: D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000601:surgery*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000453:epidemiology; D015897:Comorbidity; D003399:Craniotomy; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007360:Intelligence; D002532:Intracranial Aneurysm / Q000601:surgery*; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D009460:Neurologic Examination; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011183:Postoperative Complications / Q000175:diagnosis* / Q000453:epidemiology; D011594:Psychometrics; D012307:Risk Factors; D013223:Statistics as Topic; D013345:Subarachnoid Hemorrhage / Q000601:surgery*; D014888:Wechsler Scales / Q000706:statistics & numerical data