Mediational Pathways Among Trait Impulsivity, Heroin-use Consequences, and Current Mood State.

Background: This study examined whether lifetime heroin-use consequences mediate the relationship between trait impulsivity and three current mood outcomes: depression symptoms, stress levels, and perception of life events.

Method: Regular heroin users ( N = 163) were assessed using the Barratt Impulsiveness Scale (BIS-11) to measure trait impulsivity; a standardized Drug History and Use Questionnaire to measure lifetime adverse consequences of heroin use; Beck Depression Inventory II to measure current depression symptoms; Stress subscale of the Depression Anxiety Stress scale; and Hassles and Uplifts scale to measure perception of life events.

Results: BIS-11 Attentional and Motor impulsivity were positively related to number of adverse heroin-use consequences, depression symptoms, and stress level, and negatively associated with positive perception of events. A greater number of heroin-use consequences was related to more depression symptoms, higher stress, more negative perception of events, injection heroin use, and earlier ages of first and regular heroin use. In six mediation models, lifetime heroin-use consequences partially mediated relationships between two trait impulsivity domains (Attentional, Motor) and current mood measures (depression symptoms, stress, perception of events).

Conclusions: The present findings suggest that current negative mood can be a response to the accumulated burden of heroin-use consequences, particularly in the presence of high trait impulsivity.