Negative urgency, disinhibition and reduced temporal pole gray matter characterize the comorbidity of cocaine dependence and personality disorders

Background: Individuals with cocaine dependence and co-occurring personality disorders are more likely to have increased impulsivity, dysfunctional beliefs, executive dysfunction and brain structural abnormalities by virtue of the conjoint impact of both pathologies. Methods: We recruited 32 cocaine dependent patients with comorbid Cluster B personality disorders, 44 cocaine dependent patients without comorbidities and 34 non-drug-using controls. They completed the UPPS-P impulsivity scale, the Personality Belief Questionnaire, and executive function tests of working memory, attention/response inhibition and shifting. A subsample (n = 61) was also scanned using Magnetic Resonance Imaging. We used univariate ANOVAs for group comparisons, and tested the association between impulsivity, executive control and personality dysfunction and diagnoses using correlation and multivariate logistic regression analyses. Results: Cocaine dependent patients with personality disorders had elevated negative urgency and borderline beliefs, decreased inhibition and attention regulation, and reduced temporal pole gray matter with respect to the rest of the sample. Trait and cognitive measures correctly classified 73% of comorbid patients (60% sensitivity and 82% specificity). Conclusion: The co-occurrence of cocaine dependence and personality disorders is associated with negative-mood impulsivity and beliefs, executive dysfunction and temporal pole attrition. (C) 2013 Elsevier Ireland Ltd. All rights reserved.