Preserved cognitive function is associated with suicidal ideation and single suicide attempts in schizophrenia
ABSTRACT Suicide is the leading cause of death in schizophrenia. An association between suicidal behavior and both higher and lower cognitive ability in schizophrenia has been reported. To clarify this relationship, we investigated whether the relationship between suicidality and neurocognition varied according to differences in suicidal ideation and behavior.
Three hundred and ten patients with DSM-IV diagnoses of schizophrenia or schizoaffective disorder were categorized based on patient and staff interviews as either non-suicide attempters, non-attempters expressing suicidal ideation, single suicide attempters, or multiple suicide attempters. These groups were compared on a neuropsychological battery examining current general cognitive ability, episodic and working memory, and attentional control.
Neuropsychological performance in those with a history of suicidal ideation (n=63), and those who had made one suicide attempt (n=48) was comparable. Together, these groups outperformed patients with no history of either suicidal behavior or ideation (n=172) on measures of IQ, episodic memory and working memory. Only differences in global cognition remained significant after controlling for between-group differences in depressive symptoms. Those who had either expressed suicidal ideation and/or made a single suicide attempt demonstrated trend level advantages in neuropsychological tests over those that had made multiple suicide attempts.
These findings support earlier evidence of an association between suicidality and neurocognitive ability in schizophrenia. Specifically, these data suggest that patients who have contemplated suicide or made a single suicide attempt have better cognitive functioning than those who have not. Suicidality in multiple attempters, who do not perform better in neurocognitive tests than those who have neither contemplated nor attempted suicide, is likely to be influenced by factors other than neurocognitive ability.
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ABSTRACT: The DSM-5 includes depression as a dimension of psychosis. We tested whether persistent experience of depression, called 'trait depression', is a clinical feature separate from psychosis and several well-known, trait-like deficits of schizophrenia. 126 individuals with schizophrenia and 151 control participants completed the Maryland Trait and State Depression questionnaire, with a subset completing measures of cognition and functional capacity, and diffusion tensor imaging (n=73 patients and 102 controls for imaging analysis). Subjectively experienced, longitudinal trait depression is significantly higher in patients with schizophrenia compared with controls. Higher trait depression scores were associated with more severe psychosis. Surprisingly, individuals with higher trait depression manifested less cognitive and global functioning deficits. In addition, trait depression scores were positively associated with fractional anisotropy of white matter. Trait depression appears to be a highly relevant clinical domain in the care of patients with schizophrenia that also has distinct relationships with some other known traits of the disease. Trait depression may be an important contributor to the clinical heterogeneity of schizophrenia.Schizophrenia Research 08/2014; 159(1). DOI:10.1016/j.schres.2014.08.003 · 4.43 Impact Factor
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ABSTRACT: The lifetime risk of suicide in patients with schizophrenia is estimated to be 4.9-13%. While there are many known risk factors for suicide in schizophrenia, the relationship between cognitive function and suicide risk is unclear, particularly in non-Caucasian populations. In our cross-sectional study, we administered the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to 316 Han Chinese chronic inpatients with schizophrenia and compared the performance of those who had attempted suicide (n=25) to non-attempters (n=291). The lifetime suicide attempt data were collected from medical records and interviews with patients and their family members. We found a lifetime suicide attempt rate of 7.9%. Suicide attempters were more likely to be single, but showed no significant differences in other demographic factors such as age, gender, or living arrangements. Contrary to our hypothesis, there was no significant relationship between performance on the RBANS test and lifetime risk of suicide attempts in Han Chinese inpatients with schizophrenia. The literature remains mixed on this topic. Culturally influenced differences in suicidal behavior may have affected the outcome of this study and further investigation of this topic is necessary.Psychiatry Research 08/2014; DOI:10.1016/j.psychres.2014.07.046 · 2.68 Impact Factor
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ABSTRACT: Objectives. Suicidal behaviour results from a complex interplay between stressful events and vulnerability factors, including cognitive deficits. It is not yet clear if memory impairment is part of this specific vulnerability. Therefore, the objective of this study was to examine the association between memory deficits and vulnerability to suicidal acts. Methods. A literature review was performed using Medline, Embase, and PsycInfo databases. Twenty-four studies (including 2,595 participants) met the selection criteria. Four different types of memory (i.e., working memory, short- and long-term memory, and autobiographical memory) were assessed in at least three different studies. Results. Autobiographical memory was significantly less specific and more general in patients with a history of suicide attempt relative to those without such a history (Hedges’ g = 0.8 and 0.9, respectively). Long-term memory and working memory were both more impaired in suicide attempters than in patient and healthy controls. Only short-term memory did not differentiate suicide attempters from patient controls. Conclusions. Memory may play a significant role in the risk of suicidal acts, perhaps by preventing these individuals from using past experiences to solve current problems and to envision the future, and by altering inhibitory processes. More studies are necessary to better clarify these relationships.The World Journal of Biological Psychiatry 08/2014; DOI:10.3109/15622975.2014.925584 · 4.23 Impact Factor