RECHERCHE CANADA FRANCE USA : Inhibition cognitive dans les tentatives de suicide à haute létalité des âgés

Cognitive inhibition in older high-lethality suicide attempters

Stéphane Richard-Devantoy^1,2,  Katalin Szanto³,  Meryl A. Butters³,  Jan Kalkus³ and
Alexandre Y. Dombrovski^3,*

Article first published online: 12 MAY 2014

International Journal of Geriatric Psychiatry Volume 30, Issue 3, pages 274–283, March 2015

1 Department of Psychiatry and Douglas Mental Health University Institute, McGill Group for Suicide Studies, McGill University, Montréal, Québec, Canada
2 Laboratoire de Psychologie des Pays de la Loire EA 4638, Université de Nantes et Angers, France
3 Western Psychiatric Institute and Clinic, Department of Psychiatry, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA

^*Correspondence to: A. Y. Dombrovski. E-mail: dombax@upmc.edu

http://www.ncbi.nlm.nih.gov/pubmed/24816626

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.