title: Risk factors related to dysautonomia after severe traumatic brain injury.
abstract: BACKGROUND
  Dysautonomia after severe traumatic brain injury (TBI) is a clinical syndrome affecting a subgroup of survivors and is characterized by episodes of autonomic dysregulation and muscle overactivity. The purpose of this study was to determine the incidence of dysautonomia after severe TBI in an intensive care unit setting and analyze the risk factors for developing dysautonomia.
  
  
  METHODS
  A consecutive series of 101 patients with severe TBI admitted in a major trauma hospital during a 2-year period were prospectively observed to determine the effects of age, sex, mode of injury, hypertension history, admission systolic blood pressure, fracture, lung injury, admission Glasgow Coma Scale (GCS) score, injury severity score, emergency craniotomy, sedation or analgesia, diffuse axonal injury (DAI), magnetic resonance imaging (MRI) scales, and hydrocephalus on the development of dysautonomia. Risk factors for dysautonomia were evaluated by using logistic regression analysis.
  
  
  RESULTS
  Seventy-nine of the 101 patients met inclusion criteria, and dysautonomia was observed in 16 (20.3%) of these patients. Univariate analysis revealed significant correlations between the occurrence of dysautonomia and patient age, admission GCS score, DAI, MRI scales, and hydrocephalus. Sex, mode of injury, hypertension history, admission systolic blood pressure, fracture, lung injury, injury severity score, sedation or analgesia, and emergency craniotomy did not influence the development of dysautonomia. Multivariate logistic regression revealed that patient age and DAI were two independent predictors of dysautonomia. There was no independent association between dysautonomia and admission GCS score, MRI scales, or hydrocephalus.
  
  
  CONCLUSIONS
  Dysautonomia frequently occurs in patients with severe TBI. A younger age and DAI could be risk factors for facilitating the development of dysautonomia.
authors.affiliation: Department of Neurosurgery, Shanghai Institute of Neurosurgery, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Li-Quan
authors.initials: LQ
authors.lastname: Lv
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Hou
authors.forename: Ming-Kun
authors.initials: MK
authors.lastname: Yu
authors.forename: Xiang-Qian
authors.initials: XQ
authors.lastname: Qi
authors.forename: Huai-Rui
authors.initials: HR
authors.lastname: Chen
authors.forename: Ju-Xiang
authors.initials: JX
authors.lastname: Chen
authors.forename: Guo-Han
authors.initials: GH
authors.lastname: Hu
authors.forename: Chun
authors.initials: C
authors.lastname: Luo
authors.forename: Yi-Cheng
authors.initials: YC
authors.lastname: Lu
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001930:Brain Injuries / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D002648:Child; D015331:Cohort Studies; D003422:Critical Care; D020833:Diffuse Axonal Injury / Q000150:complications / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D054969:Primary Dysautonomias / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D012307:Risk Factors; D055815:Young Adult