McGill University, Department of Psychiatry & Douglas Mental Health University Institute McGill Group for Suicide Studies Montréal, Québec, Canada.
J Affect Disord. 2012 Oct;140(2):193-9. doi: 10.1016/j.jad.2012.03.006. Epub 2012 Mar 29.
Cognitive deficits, in relation to ventral and dorsal prefrontal cortex dysfunctions, have been associated with a higher risk of suicidal acts in young adult patients. Although a public health concern, much less is known about the neurocognitive basis of suicidal behavior in elderly. Here, we aimed at assessing alterations in cognitive inhibition, a suspected major mechanism of the suicidal vulnerability, in suicidal depressed elderly.
We compared 20 currently depressed patients, aged 65 and older who recently attempted suicide to 20 elderly subjects with a current depression but no personal history of suicide attempt and 20 elderly controls. Using an extensive neuropsychological battery, we particularly examined different aspects of cognitive inhibition: access to relevant information (using the Reading with distraction task), suppression of no longer relevant information (Trail Making Test, Rule Shift Cards), and restraint of cognitive resources to relevant information (Stroop test, Hayling Sentence Completion test, Go/No-Go).
After adjustment for age, intensity of depression, Mini-Mental State Examination score and speed of information processing, suicidal depressed elderly showed significant impairments in all 3 domains of cognitive inhibition in comparison to both control groups.
Our results need replication in a larger sample size.
Our study suggests that the inability to inhibit neutral information access to working memory, restrain and delete irrelevant information may impair the patient's capacity to respond adequately to stressful situations subsequently leading to an increased risk of suicidal behavior during late-life depression. Interventions may be developed to specifically target cognitive impairment in the prevention of suicide in depressed elderly.
认知缺陷与腹侧和背侧前额叶皮层功能障碍有关，与年轻成年患者自杀行为的风险增加有关。尽管这是一个公共卫生问题，但人们对老年患者自杀行为的神经认知基础知之甚少。在这里，我们旨在评估自杀性抑郁老年患者认知抑制的变化，认知抑制是自杀易感性的一个主要潜在机制。
我们比较了 20 名年龄在 65 岁及以上且最近有过自杀企图的目前抑郁的患者，20 名有当前抑郁但没有自杀企图个人史的老年患者和 20 名老年对照组。使用广泛的神经心理学测试，我们特别检查了认知抑制的不同方面：获取相关信息（使用分心阅读任务），抑制不再相关的信息（连线测试，规则转换卡片），以及对相关信息的认知资源的约束（Stroop 测试，Hayling 句子完成测试，Go/No-Go 测试）。
在调整年龄、抑郁严重程度、简易精神状态检查评分和信息处理速度后，与对照组相比，自杀性抑郁的老年患者在认知抑制的所有 3 个领域均表现出显著的损伤。
我们的结果需要在更大的样本量中进行复制。
我们的研究表明，无法抑制中性信息进入工作记忆，无法抑制和删除无关信息，可能会损害患者对紧张情况做出适当反应的能力，随后导致老年期抑郁症自杀行为的风险增加。可能会开发干预措施来专门针对认知障碍，以预防老年抑郁患者的自杀。
