title: Cognitive inhibition in older high-lethality suicide attempters.
abstract: BACKGROUND
  People who attempt suicide often display cognitive impairments, particularly poor cognitive control. Could poor cognitive control contribute to high suicide rates in old age? A component of cognitive control, cognitive inhibition-active suppression of task-irrelevant processing-is very sensitive to aging and has been linked to attempted suicide. We investigated cognitive inhibition in older high-lethality suicide attempters, closely resembling suicide victims, as well as low-lethality attempters, and control groups with and without depression and suicidal ideation.
  
  
  METHODS
  A total of 102 participants aged 60 years and older (17 psychiatrically healthy control subjects, 38 depressed control subjects, 16 suicide ideators, 14 low-lethality suicide attempters, and 17 high-lethality suicide attempters) underwent comprehensive clinical and cognitive assessments. They completed the Delis-Kaplan Executive Function System Color-Word Interference Test, a validated modification of the Stroop test.
  
  
  RESULTS
  High-lethality suicide attempters demonstrated a distinct pattern of cognitive inhibition deficits. Compared with psychiatrically healthy control subjects and suicide ideators, high-lethality attempters took longer to complete inhibition trials, even after accounting for potential confounding factors (age, education, Mini mental state examination score, information processing speed, and accuracy). Compared with non-suicidal depressed and healthy control subjects, low-lethality suicide attempters committed more uncorrected errors; however, this difference was not specific to the inhibition condition.
  
  
  CONCLUSIONS
  Older suicide attempters are a cognitively heterogeneous group. Poor cognitive control in high-lethality attempters may undermine their ability to solve real-life problems, precipitating a catastrophic accumulation of stressors. Meanwhile, low-lethality attempters' poor performance may reflect a careless approach to the task or faulty monitoring.
authors.affiliation: Department of Psychiatry and Douglas Mental Health University Institute, McGill Group for Suicide Studies, McGill University, Montréal, Québec, Canada; Laboratoire de Psychologie des Pays de la Loire EA 4638, Université de Nantes et Angers, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Richard-Devantoy
authors.forename: Katalin
authors.initials: K
authors.lastname: Szanto
authors.forename: Meryl A
authors.initials: MA
authors.lastname: Butters
authors.forename: Jan
authors.initials: J
authors.lastname: Kalkus
authors.forename: Alexandre Y
authors.initials: AY
authors.lastname: Dombrovski
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000523:psychology*; D003866:Depressive Disorder / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011340:Problem Solving; D013406:Suicide, Attempted / Q000523:psychology*
keywords: Stroop; cognitive control; mood disorders; neuropsychology; suicidal behavior