title: Decision making under explicit risk is impaired in individuals with human immunodeficiency virus (HIV).
abstract: BACKGROUND
  Human immunodeficiency virus (HIV) can affect the frontal-striatal brain regions, which are known to subserve decision-making functions. Previous studies have reported impaired decision making among HIV+ individuals using the Iowa Gambling Task, a task that assesses decision making under ambiguity. Previous study populations often had significant comorbidities such as past or present substance use disorders and/or hepatitis C virus coinfection, complicating conclusions about the unique contributions of HIV-infection to decision making. Decision making under explicit risk has very rarely been examined in HIV+ individuals and was tested here using the Game of Dice Task (GDT).
  
  
  METHODS
  We examined decision making under explicit risk in the GDT in 20 HIV+ individuals without substance use disorder or HCV coinfection, including a demographically matched healthy control group (n = 20). Groups were characterized on a standard neuropsychological test battery. For the HIV+ group, several disease-related parameters (viral load, current and nadir CD4 T-cell count) were included. Analyses focused on the GDT and spanned between-group (t-tests; analysis of covariance, ANCOVA) as well as within-group comparisons (Pearson/Spearman correlations).
  
  
  RESULTS
  HIV+ individuals were impaired in the GDT, compared to healthy controls (p = .02). Their decision-making impairments were characterized by less advantageous choices and more random choice strategies, especially towards the end of the task. Deficits in the GDT in the HIV+ group were related to executive dysfunctions, slowed processing/motor speed, and current immune system status (CD4+ T-cell levels, ps < .05).
  
  
  CONCLUSIONS
  Decision making under explicit risk in the GDT can occur in HIV-infected individuals without comorbidities. The correlational patterns may point to underlying fronto-subcortical dysfunctions in HIV+ individuals. The GDT provides a useful measure to assess risky decision making in this population and should be tested in larger studies.
authors.affiliation: a Department of Psychiatry , University of Alberta , Edmonton , AB , Canada.
authors.forename: Esther
authors.initials: E
authors.lastname: Fujiwara
authors.forename: Sara E
authors.initials: SE
authors.lastname: Tomlinson
authors.forename: Scot E
authors.initials: SE
authors.lastname: Purdon
authors.forename: M John
authors.initials: MJ
authors.lastname: Gill
authors.forename: Christopher
authors.initials: C
authors.lastname: Power
mesh_terms: D000328:Adult; D003657:Decision Making / Q000502:physiology*; D004644:Emotions / Q000502:physiology; D056344:Executive Function / Q000502:physiology; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000523:psychology*; D006526:Hepatitis C / Q000150:complications / Q000523:psychology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012309:Risk-Taking
keywords: Decision making; Executive functions; Game of Dice Task; Human immunodeficiency virus; Neuropsychology