(PS11-C52) A Longitudinal Evaluation of Stressful Life Events and Substance Use in At-risk Adolescents: The Moderating Role of Impulsivity

Although the association between stressful life events   and problematic substance use in adolescents is well-documented, the neurocognitive and personality factors that influence this association are not yet fully understood. Impulsivity is a multidimensional construct, encompassing state-sensitive behavioral responses (e.g., response inhibition), cognitive processes (e.g., impulsive decision making), and personality trait factors (e.g., sensation seeking), that are implicated in the development and maintenance of problematic substance use in adolescents. However, most studies to date narrowly conceptualize impulsivity, examining self-reported impulsive personality traits   only (e.g., lack of perseverance and premeditation, and negative urgency). Thus, less is known about the role of behavioral and cognitive impulsivity in the relation between stressful life events and substance use. The current study addresses this gap by examining whether behavioral, cognitive, and self-reported impulsivity influence the degree to which stressful life events at baseline are associated with substance use six months later. Analyses included a sample of 153 adolescents (Mage = 14.89, SD = 1.35; 71.67% female) recruited from a psychiatric inpatient hospital. At baseline, neurocognitive tasks, including the stop signal task assessing behavioral impulsivity and the delayed discounting task assessing cognitive impulsivity, and the UPPS Impulsive Behavior Scale, a self-report measure of impulsive personality traits, and a contextual threat interview assessing stressful life events (events dependent at least in part on the individual) were administered. At the six-month follow-up, rates of past-month alcohol and marijuana use were collected using timeline follow-back. Regression analyses revealed that the interactions between baseline stressful life events and behavioral (B = .002, p = .04) and self-reported impulsivity (B = .39, p < .001) accounted for unique variance in alcohol use at six months. At high levels of behavioral and self-reported impulsivity, life stress was positively associated with alcohol consumption six months later. In contrast, when behavioral and self-reported impulsivity were low, life stress did not predict alcohol consumption at six months.  In the future, multidimensional assessments of impulsivity may provide insight into which individuals are at higher risk for problematic substance use following psychiatric hospitalization. Further investigation is necessary to uncover the mechanisms by which different dimensions of impulsivity influence the association between stressful life events and subsequent substance use.