title: Delayed intracranial complications after concussion.
abstract: METHODS
  The incidence of readmissions because of delayed intracranial complications within 3 weeks after observation for the sole diagnosis of concussion was examined in a national cohort. A nested case-control design was used to analyze the association between clinical factors as well as early computed tomography (CT) scan examination and these complications.
  
  
  RESULTS
  Out of 100,784 patients hospitalized because of concussion during ten years, 127 (0.13%) patients were readmitted because of a delayed intracranial complication. High clinical severity grade (odds ratio [OR] 2.0, confidence interval [CI] 1.2-3.6), minor CT scan abnormalities (OR 1.7, CI 0.8-3.4) and male gender (OR 2.2, CI 1.4-3.5) were associated with an increased risk of delayed, intracranial complications.
  
  
  CONCLUSIONS
  The incidence of delayed intracranial complications after primarily uncomplicated concussion was low. High clinical severity grade and male gender were risk factors. We failed to demonstrate an additional value of the acute CT scan examination to predict these complications.
authors.affiliation: Department of Rehabilitation Medicine, Karolinska Institutet, Stockholm, Sweden. catharina.deboussard@ds.se
authors.forename: Catharina Nygren
authors.initials: CN
authors.lastname: de Boussard
authors.forename: Rino
authors.initials: R
authors.lastname: Bellocco
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: af Geijerstam
authors.forename: Jörgen
authors.initials: J
authors.lastname: Borg
authors.forename: Johanna
authors.initials: J
authors.lastname: Adami
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001924:Brain Concussion / Q000150:complications* / Q000453:epidemiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015994:Incidence; D015601:Injury Severity Score; D020300:Intracranial Hemorrhages / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012042:Registries; D012887:Skull Fractures / Q000000981:diagnostic imaging; D013548:Sweden / Q000453:epidemiology; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data