title: "Latent" infection with Toxoplasma gondii: association with trait aggression and impulsivity in healthy adults.
abstract: BACKGROUND
  Latent chronic infection with Toxoplasma gondii (T. gondii), a common neurotropic pathogen, has been previously linked with suicidal self-directed violence (SSDV). We sought to determine if latent infection with T. gondii is associated with trait aggression and impulsivity, intermediate phenotypes for suicidal behavior, in psychiatrically healthy adults.
  
  
  METHODS
  Traits of aggression and impulsivity were analyzed in relationship to IgG antibody seropositivity for T. gondii and two other latent neurotropic infections, herpes simplex virus 1 (HSV1) and cytomegalovirus (CMV). One thousand community-residing adults residing in the Munich metropolitan area with no Axis I or II conditions by SCID for DSM-IV (510 men, 490 women, mean age 53.6 ± 15.8, range 20-74). Plasma samples were tested for IgG antibodies to T. gondii, HSV-1 and CMV by ELISA. Self-reported ratings of trait aggression scores (Questionnaire for Measuring Factors of Aggression [FAF]) and trait impulsivity (Sensation-Seeking Scale-V [SSS-V]) were analyzed using linear multivariate methods.
  
  
  RESULTS
  T. gondii IgG seropositivity was significantly associated with higher trait reactive aggression scores among women (p < .01), but not among men. T. gondii-positivity was also associated with higher impulsive sensation-seeking (SSS-V Disinhibition) among younger men (p < .01) aged 20-59 years old (median age = 60). All associations with HSV-1 and CMV were not significant.
  
  
  CONCLUSIONS
  Aggression and impulsivity, personality traits considered as endophenotypes for SSDV, are associated with latent T. gondii infection in a gender and age-specific manner, and could be further investigated as prognostic and treatment targets in T. gondii-positive individuals at risk for SSDV.
authors.affiliation: Department of Public Health, Mercyhurst Institute for Public Health, Mercyhurst University, Erie, PA, USA.
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Cook
authors.affiliation: Veterans Integrated Service Network (VISN) 19, Mental Illness Research Education and Clinical Center (MIRECC), Denver, CO, USA; Department of Psychiatry, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA; Department of Physical Medicine and Rehabilitation, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA; Department of Neurology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Brenner
authors.affiliation: Department of Psychiatry, Sansone Centre for Well-Being, Washington University, St. Louis, MO, USA.
authors.forename: C Robert
authors.initials: CR
authors.lastname: Cloninger
authors.affiliation: Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD, USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Langenberg
authors.affiliation: DC Department of Behavioral Health, Saint Elizabeths Hospital, Psychiatry Residency Program, Washington, DC, USA.
authors.forename: Ajirioghene
authors.initials: A
authors.lastname: Igbide
authors.affiliation: Department of Psychiatry, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
authors.forename: Ina
authors.initials: I
authors.lastname: Giegling
authors.affiliation: Department of Psychiatry, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
authors.forename: Annette M
authors.initials: AM
authors.lastname: Hartmann
authors.affiliation: Department of Psychiatry, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
authors.forename: Bettina
authors.initials: B
authors.lastname: Konte
authors.affiliation: Department of Psychiatry, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
authors.forename: Marion
authors.initials: M
authors.lastname: Friedl
authors.affiliation: Division of Psychiatry and Behavioral Medicine, College of Human Medicine, Michigan State University, Van Andel Research Institute, Grand Rapids, MI, USA.
authors.forename: Lena
authors.initials: L
authors.lastname: Brundin
authors.affiliation: University of South Florida, Tampa, FL, USA.
authors.forename: Maureen W
authors.initials: MW
authors.lastname: Groer
authors.affiliation: Department of Psychiatry, University of Maryland-Baltimore School of Medicine, Baltimore, MD, USA.
authors.forename: Adem
authors.initials: A
authors.lastname: Can
authors.affiliation: Department of Psychiatry, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
authors.forename: Dan
authors.initials: D
authors.lastname: Rujescu
authors.affiliation: Veterans Integrated Service Network (VISN) 19, Mental Illness Research Education and Clinical Center (MIRECC), Denver, CO, USA; Department of Psychiatry, University of Maryland-Baltimore School of Medicine, Baltimore, MD, USA; Veterans Integrated Service Network (VISN) 5, Mental Illness Research Education and Clinical Center (MIRECC), Baltimore, MD, USA. Electronic address: tpostolache@psych.umaryland.edu.
authors.forename: Teodor T
authors.initials: TT
authors.lastname: Postolache
mesh_terms: D000328:Adult; D000368:Aged; D000374:Aggression / Q000523:psychology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007175:Impulsive Behavior; D008297:Male; D008875:Middle Aged; D010551:Personality; D010552:Personality Assessment; D012307:Risk Factors; D059020:Suicidal Ideation; D014122:Toxoplasma / Q000276:immunology*; D014123:Toxoplasmosis / Q000276:immunology / Q000523:psychology*; D014754:Violence; D055815:Young Adult
chemical_list: D007074:Immunoglobulin G
keywords: Aggression; Impulsivity; Personality; Toxoplasma gondii