Objective: This study aimed to examine whether subjects with history of suicidal attempts had higher impulsivity as measured by neurocognitive tests and self-report questionnaires. The interrelationships among different impulsivity measures were also explored.
Methods: Fifty-four nonpsychotic psychiatric inpatients, including 24 subjects with previous history of suicidal attempts and 30 comparison subjects without previous suicidal attempts, completed the self-report Barratt Impulsiveness Scale-11-Chinese version (BIS-11-CH) and 2 neuropsychologic tests of impulsivity: the immediate memory task/delayed memory task (IMT/DMT) and the single key impulsivity paradigm (SKIP).
Results: The results indicated that subjects with previous suicidal attempts exhibited higher BIS-11-CH factor 2 (lack of self-control/attentional impulsivity) subscore (P = .02) and more commission errors in IMT (P = .03). However, BIS-11-CH scores and performance indices of IMT/DMT and of SKIP did not correlate with each other.
Conclusions: Our findings supported that subjects with previous suicidal attempts had higher impulsivity, which could be revealed by both self-report and neurocognitive measures. However, there is no correlation among self-report, IMT/DMT, and SKIP measures, indicating that they might be measuring different dimensions of impulsivity.