title: Incidence and predictors of intracranial hemorrhage after minor head trauma in patients taking anticoagulant and antiplatelet medication.
abstract: BACKGROUND
  The yield of head computed tomography (CT) for patients who suffered head trauma with a presenting Glasgow Coma Scale (GCS) score of 15 has been reported to be low, even in patients who are anticoagulated or on antiplatelet therapy. We undertook this study to (1) determine the frequency of intracranial hemorrhage in anticoagulated patients and patients on antiplatelet therapy and its impact on clinical management, (2) identify predictors of positive imaging findings, and (3) assess potential differences between anticoagulation and antiplatelet therapy.
  
  
  METHODS
  We conducted a retrospective review of the trauma registry at our institution, a Level II trauma center. All trauma registry patients with a minor head injury registered between the years 2004 and 2006 who were taking warfarin or clopidogrel, had a presenting GCS score of 15, and underwent head CT were included in this study. Intracranial hemorrhage on head CT was considered a positive result.
  
  
  RESULTS
  One hundred forty-one patients (male, n=67; female, n=74), mean age 79 years (range, 36-101 years), were included in this study. Forty-one patients (29%) were diagnosed with intracranial hemorrhage. Thirty-nine (95%) of these 41 patients underwent reversal and/or discontinuation of clopidogrel and/or warfarin. Five patients required surgical evacuation of an intracranial hemorrhage. Four patients died. Loss of consciousness (Wald=7.468, β=1.179, p=0.008) predicted a positive CT result. Type of medication (warfarin, aspirin, or clopidogrel) did not reach statistical significance as a predictor of positive result.
  
  
  CONCLUSIONS
  Despite a presenting GCS score of 15, patients with minor head injury from the trauma registry at our institution taking anticoagulation or antiplatelet therapy have a high incidence of intracranial hemorrhage especially after reported loss of consciousness.
authors.affiliation: Department of Diagnostic Radiology, Lahey Clinic Medical Center, Burlington, Massachusetts 01805, USA. edward.s.brewer@lahey.org
authors.forename: Edward S
authors.initials: ES
authors.lastname: Brewer
authors.forename: Boris
authors.initials: B
authors.lastname: Reznikov
authors.forename: Rebecca F
authors.initials: RF
authors.lastname: Liberman
authors.forename: Richard A
authors.initials: RA
authors.lastname: Baker
authors.forename: Michael S
authors.initials: MS
authors.lastname: Rosenblatt
authors.forename: Carlos A
authors.initials: CA
authors.lastname: David
authors.forename: Sebastain
authors.initials: S
authors.lastname: Flacke
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000009:adverse effects*; D000077144:Clopidogrel; D006259:Craniocerebral Trauma / Q000150:complications* / Q000000981:diagnostic imaging; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D015994:Incidence; D020198:Intracranial Hemorrhage, Traumatic / Q000139:chemically induced* / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects*; D012189:Retrospective Studies; D013988:Ticlopidine / Q000009:adverse effects / Q000031:analogs & derivatives*; D014057:Tomography, X-Ray Computed; D014193:Trauma Centers / Q000706:statistics & numerical data; D014859:Warfarin / Q000009:adverse effects*
chemical_list: D000925:Anticoagulants; D010975:Platelet Aggregation Inhibitors; D014859:Warfarin; D000077144:Clopidogrel; D013988:Ticlopidine