title: Risk, types, and severity of intracranial hemorrhage in patients with symptomatic carotid artery stenosis.
abstract: OBJECTIVE
  We sought to report the occurrence and risk factors of intracranial hemorrhage during long-term follow-up of patients with internal carotid artery stenosis, with and without carotid endarterectomy.
  
  
  METHODS
  From the prospective data of the North American Symptomatic Carotid Endarterectomy Trial, 3 types of intracranial hemorrhage were recognized: petechiae within infarction (PTI), intracerebral hematoma (ICH), and subarachnoid hemorrhage (SAH). The 30-day and 5-year risks of intracranial hemorrhage (PTI or ICH) were estimated from Kaplan-Meier event-free survival curves. Cox proportional-hazards regression modeling was used to identify risk factors.
  
  
  RESULTS
  Of 1039 strokes that occurred in 749 of 2885 patients during an average follow-up of 5 years, there were 24 PTIs, 14 ICHs, and 1 SAH. The 5-year risk of intracranial hemorrhage was 1.7% in both medically and surgically treated patients, but the 30-day risk of 0.64% in surgically treated patients was 10 times higher than the risk of 0.07% in medically treated patients (P=0.01). Approximately 50% of all intracranial hemorrhages were either disabling or fatal, and ICHs were more likely to be fatal than PTIs. Old age, a history of hypertension, intermittent claudication and smoking, and infarct on brain images were risk factors for intracranial hemorrhage in medically treated patients, whereas diabetes mellitus was the sole risk factor in surgically treated patients.
  
  
  CONCLUSIONS
  Intracranial hemorrhages are uncommon in patients with internal carotid artery stenosis but are associated with high mortality and morbidity. The risk factors for intracranial hemorrhage are different between medically and surgically treated patients.
authors.affiliation: University Department of Medicine, University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong King, China. rtcheung@hkucc.hku.hk
authors.forename: Raymond T F
authors.initials: RT
authors.lastname: Cheung
authors.forename: Michael
authors.initials: M
authors.lastname: Eliasziw
authors.forename: Heather E
authors.initials: HE
authors.lastname: Meldrum
authors.forename: Allan J
authors.initials: AJ
authors.lastname: Fox
authors.forename: Henry J M
authors.initials: HJ
authors.lastname: Barnett
mesh_terms: D016893:Carotid Stenosis / Q000453:epidemiology* / Q000601:surgery; D015897:Comorbidity; D018572:Disease-Free Survival; D016894:Endarterectomy, Carotid / Q000706:statistics & numerical data; D005500:Follow-Up Studies; D006801:Humans; D020300:Intracranial Hemorrhages / Q000453:epidemiology* / Q000401:mortality; D015337:Multicenter Studies as Topic / Q000706:statistics & numerical data; D009656:North America / Q000453:epidemiology; D016016:Proportional Hazards Models; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D018570:Risk Assessment; D012307:Risk Factors