Relationship of personality traits and drug of choice by cocaine addicts and heroin addicts.

The link between specific personality profiles and a single psychotropic drug of choice is still unclear and only partially explored. The present study compares three groups of male subjects: 85 patients manifesting heroin dependence (age: 30.07 +/- 2.78), 60 patients manifesting cocaine dependence (age: 31.96 +/- 3.1), and 50 healthy subjects from a random population sample (age: 33.25 +/- 1.45). The patients included in the study showed a long-lasting history of dependence on heroin or cocaine, respectively, 5.2 +/- 2.5 years, 4.6 +/- 2.9 years, and were stabilized in treatment, and abstinent, at least 4 weeks at the time of the diagnostic assessment. Heroin addicts (52.90%) were on methadone maintenance treatment. Cocaine addicts (11.60%) were treated with selective serotonin reuptake inhibitors. Personality traits were measured by the Minnesota Multiphasic Personality Inventory (MMPI-2) and Cloninger's Three-dimensional Personality Questionnaire (TPQ). Character and quantification of aggressiveness were measured by the Buss-Durkee Hostility Inventory (BDHI). Heroin-dependent patients (group A) scored significantly higher on hysteria, masculine-feminine and social introversion subscales of the MMPI, and significantly lower on the harm avoidance (HA) subscale of the TPQ than cocaine addicts. In contrast, scores on the MMPI for hypochondria, psychopathic deviance, and paranoia dimensions were more elevated in cocaine addicts than in heroin-dependent patients. Cocaine addicts scored higher than heroin addicts on the "direct" aggressiveness subscale and on the BDHI total score. Cocaine addicts did not differ from healthy controls on harm avoidance (behavioral control). Although cocaine addicts showed more consistent psychopathic deviance and overt aggressiveness than heroin addicts, higher harm avoidance (behavioral control), hypochondria (or worry about their health), and social extroversion may reduce their proneness to overt antisocial behavior and allow relatively higher levels of social integration. The study's limitations are noted.