Abstract
Objective: Heroin dependence is associated with deficits in impulsivity, which is also a core feature of attention deficit hyperactivity disorder (ADHD). This study aimed to explore the association between childhood ADHD symptoms and cognitive and motor impulsivity among abstinent individuals with a history of heroin dependence. Methods: Thirty-two abstinent Bulgarian males with a history of heroin dependence participated in the study. Self-rated childhood ADHD symptoms were obtained using the Wender-Utah Rating Scale. Cognitive impulsivity was measured using the Iowa Gambling Task (IGT), an index of impulsive decision making, and the Delayed Reward Discounting Task (DRDT), a measure of intertemporal choice. Motor impulsivity was indexed with the Stop Signal Task (SST), a measure of response inhibition. Results: Participants, whose average age was 27.66 years (SD = 2.7), had an average ADHD symptom score of 36.6 (SD = 18.6), had roughly 7 years (SD = 2.9) of heroin use, and had been abstinent for just over a year (M = 402.5 days, SD = 223.8). Linear regression analyses revealed that self-reported ADHD symptoms predicted impulsive decision making (IGT), but not delayed discounting (DRDT) or response inhibition (SST). Conclusions: Self-reported childhood ADHD symptoms do not uniformly predict impulsivity among abstinent individuals with heroin dependence. Results suggest the IGT may be more sensitive to externalizing psychopathology among individuals with heroin dependence than other measures of impulsivity.
ACKNOWLEDGMENTS
The authors thank all study participants for their role in this study.
DISCLOSURES
The authors report no financial relationships with commercial interests with regard to this manuscript. Dr. Vasilev is the director of the Bulgarian Addictions Institute, where the study was conducted. Drs. Vassileva and Gonzalez received research funding from the National Institutes of Health (NIH). The content is solely the responsibility of the authors and does not necessarily represent the official view of the NIH.
FUNDING
This study was funded by grants R21DA025417 (JV) from NIDA and R01DA021421 (JV) from NIDA and the Fogarty International Center.