Richard-Devantoy Stéphane, Szanto Katalin, Butters Meryl A, Kalkus Jan, Dombrovski Alexandre Y
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.
Int J Geriatr Psychiatry. 2015 Mar;30(3):274-83. doi: 10.1002/gps.4138. Epub 2014 May 12.
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.
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.
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.
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.
企图自杀的人往往存在认知障碍，尤其是认知控制能力差。认知控制能力差是否会导致老年人自杀率居高不下？认知控制的一个组成部分，即认知抑制——对与任务无关的加工进行主动抑制——对衰老非常敏感，并且与自杀未遂有关。我们调查了高致死性自杀未遂者（与自杀受害者极为相似）、低致死性自杀未遂者以及有和没有抑郁及自杀意念的对照组的认知抑制情况。
共有102名60岁及以上的参与者（17名精神健康的对照者、38名抑郁对照者、16名有自杀意念者、14名低致死性自杀未遂者和17名高致死性自杀未遂者）接受了全面的临床和认知评估。他们完成了德利斯科-卡普兰执行功能系统颜色-词语干扰测试，这是对斯特鲁普测试的一种经过验证的改良版测试。
高致死性自杀未遂者表现出一种独特的认知抑制缺陷模式。与精神健康的对照者和有自杀意念者相比，即使在考虑了潜在的混杂因素（年龄、教育程度、简易精神状态检查得分、信息处理速度和准确性）之后，高致死性自杀未遂者完成抑制试验所需的时间仍更长。与非自杀性抑郁和健康对照者相比，低致死性自杀未遂者出现的未纠正错误更多；然而，这种差异并非抑制条件所特有。
老年自杀未遂者是一个认知异质性群体。高致死性自杀未遂者认知控制能力差可能会削弱他们解决现实生活问题的能力，从而导致压力源灾难性地累积。与此同时，低致死性自杀未遂者表现不佳可能反映出他们对任务的粗心态度或监测失误。
