title: S100B levels are affected by older age but not by alcohol intoxication following mild traumatic brain injury.
abstract: BACKGROUND
  Biomarkers of brain damage and head injury are potentially useful tools in the management of afflicted patients. Particularly S100B has received much attention and has been adapted into clinical guidelines. Alcohol intoxication and higher age (65 years and over) have been used as risk factors for serious complications following head injury. The effect of these factors on S100B levels has not been fully established in a relevant patient cohort.
  
  
  METHODS
  We prospectively included 621 adult patients with mild traumatic brain injury (TBI) and S100B sampling. Mild TBI was defined as Glasgow Come Scale 14-15 with loss of consciousness and/or amnesia, but without high-risk factors for intracranial complications. These patients would normally require CT scanning according to local and most international guidelines. S100B was sampled within 3 hours following trauma.
  
  
  RESULTS
  280 patients (45%) were intoxicated by alcohol. Alcohol intoxication had no effect on S100B levels (p = 0.65) and the performance of S100B remained unchanged in these patients. 115 patients (22%) were 65 years or older with elevated S100B levels being more common in this group compared to patients under 65 (p = 0.029). Although the sensitivity of S100B was unchanged in older patients, the specificity was poorer.
  
  
  CONCLUSIONS
  S100B can be used reliably in mild TBI patients with alcohol intoxication. The clinically utility of S100B in older patients may be limited by very poor specificity leading to only a small decrease in CT scanning.
authors.forename: Olga
authors.initials: O
authors.lastname: Calcagnile
authors.forename: Anders
authors.initials: A
authors.lastname: Holmén
authors.forename: Michelle
authors.initials: M
authors.lastname: Chew
authors.forename: Johan
authors.initials: J
authors.lastname: Undén
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000435:Alcoholic Intoxication / Q000097:blood* / Q000175:diagnosis; D015415:Biomarkers / Q000097:blood; D001930:Brain Injuries / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D015600:Glasgow Coma Scale; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D012307:Risk Factors; D064568:S100 Calcium Binding Protein beta Subunit / Q000097:blood*; D013548:Sweden / Q000453:epidemiology; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D015415:Biomarkers; D064568:S100 Calcium Binding Protein beta Subunit; C579160:S100B protein, human