title: Exploratory associations with tumor necrosis factor-α, disinhibition and suicidal endorsement after traumatic brain injury.
abstract: OBJECTIVE
  To examine the relationship of Tumor Necrosis Factor (TNF)-α to disinhibition and suicidal endorsement after traumatic brain injury (TBI).
  
  
  METHODS
  Adults with moderate to severe TBI (acute serum levels: n=48, n=543 samples; acute CSF levels: n=37, n=389 samples; chronic serum levels: n=48, n=326 samples).
  
  
  METHODS
  TNFα levels (CSF, Serum) from time of injury to 12 months post-injury; Frontal Systems Behavior Scale - Disinhibition Subscale at 6 and 12 months post-injury; Patient Health Questionnaire at 6 and 12 months post-injury.
  
  
  RESULTS
  Participants with TBI had significantly higher CSF and serum TNFα levels than healthy controls (p<0.05). Acute and chronic serum TNFα was significantly associated with disinhibition at 6 months post-injury (p=0.009, p=0.029 respectively), and 6 month disinhibition was associated with suicidal endorsement at both 6 and 12 months (p=0.045, p=0.033 respectively) and disinhibition at 12 months post-injury (p<0.001).
  
  
  CONCLUSIONS
  These preliminary data suggest a biological to behavioral pathway of suicidality after TBI, from TNFα to disinhibition to suicidal endorsement. Future investigation is warranted to validate these findings and clarify what biological mechanisms might underlie these relationships.
authors.affiliation: Dept. Physical Medicine and Rehabilitation, University of Pittsburgh, United States.
authors.forename: S B
authors.initials: SB
authors.lastname: Juengst
authors.affiliation: Dept. Physical Medicine and Rehabilitation, University of Pittsburgh, United States.
authors.forename: R G
authors.initials: RG
authors.lastname: Kumar
authors.affiliation: Dept. Physical Medicine and Rehabilitation, University of Pittsburgh, United States.
authors.forename: P M
authors.initials: PM
authors.lastname: Arenth
authors.affiliation: Dept. Physical Medicine and Rehabilitation, University of Pittsburgh, United States; Center for Neuroscience, University of Pittsburgh, United States; Safar Center for Resuscitation Research, University of Pittsburgh, United States. Electronic address: wagnerak@upmc.edu.
authors.forename: A K
authors.initials: AK
authors.lastname: Wagner
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001293:Attitude to Death; D015415:Biomarkers; D001930:Brain Injuries / Q000097:blood / Q000134:cerebrospinal fluid / Q000523:psychology*; D003865:Major Depressive Disorder / Q000097:blood / Q000134:cerebrospinal fluid / Q000209:etiology / Q000523:psychology; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000502:physiology; D007249:Inflammation / Q000097:blood / Q000134:cerebrospinal fluid / Q000378:metabolism*; D007266:Inhibition, Psychological; D008297:Male; D008875:Middle Aged; D016728:Self-Injurious Behavior / Q000097:blood / Q000523:psychology; D059020:Suicidal Ideation; D011795:Surveys and Questionnaires; D017741:Survivors / Q000523:psychology*; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis* / Q000097:blood / Q000134:cerebrospinal fluid; D055815:Young Adult
chemical_list: D015415:Biomarkers; D014409:Tumor Necrosis Factor-alpha
keywords: Brain injury; Depression; Disinhibition; Impulsivity; Inflammation; Suicide; Tumor Necrosis Factor-Alpha