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

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. 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.