Optimal neurocognitive, personality and behavioral measures for assessing impulsivity in cocaine dependence

Abstract

Background: Impulsivity may underlie the poor treatment retention and high relapse rates observed in cocaine-dependent persons. However, observed differences in measures of impulsivity between cocaine-dependent and healthy control participants often do not reach clinical significance, suggesting that the clinical relevance of these differences may be limited. Objectives: To examine which measures of impulsivity (i.e. self-report impulsivity, self-report personality, neurocognitive testing) best distinguish cocaine-dependent and healthy control participants (i.e. showing differences at least 1.5 standard deviations [SD] from controls). Optimal measures were considered to demonstrate sufficient classification accuracy. Methods: Sixty-five recently abstinent cocaine-dependent and 25 healthy control participants were assessed using select neurocognitive tests and self-report questionnaires including the NEO Personality Inventory-Revised (NEO-PI-R), Temperament and Character Inventory (TCI), Barratt Impulsiveness Scale (BIS-11a), and the Frontal Systems Behavior Scale (FrSBe). Results: When corrected for years of education and gender, neurocognitive measures did not demonstrate clinically significant differences between cocaine-dependent and control participants. The personality measures TCI Purposefulness and Congruent Second Nature and NEO-PI-R Impulsiveness, and the self-rating measures FrSBe Disinhibition and BIS-11 Motor Impulsivity and Total successfully identified clinically meaningful elevations in impulsivity within cocaine-dependent participants (>1.5 SDs from controls). Furthermore, these measures achieved 84–93% accuracy in discriminating cocaine-dependent from control participants. Conclusion: Clinically significant neurocognitive impairment in cocaine-dependent participants was not observed in this sample. As the BIS-11 or FrSBe are brief to administer, accurate, and have been shown to predict treatment retention and relapse, these measures appear to be optimal, relative to the personality measures, for examining trait impulsivity in cocaine dependence.

• BIS-11
• cocaine dependence
• FrSBe
• impulsivity
• neurocognitive

Acknowledgements

We are grateful for the assistance of the staff on the Substance Abuse Team at the VA North Texas Health Care System, Homeward Bound, Inc., and Nexus Recovery Center for their support in the screening and recruitment of study participants. This study was supported by the National Institute on Drug Abuse grant DA023203 and the UT Southwestern Center for Translational Medicine UL1TR000451.

Supplementary Material Available Online

Derivation and validation of the neurocognitive and self-rating measures.

Supplementary content can be viewed and downloaded at http://informahealthcare.com/ada