Diana R. Samek, Ph.D.
Ph.D., University of Minnesota, 2012
(334) 844-3173 | 203 Spidle Hall
College Experiences Leading to Alcohol and Cannabis Use Disorder Onset, Persistence, and Desistence: A Longitudinal Study ($50,000 total costs, AAES Young Investigator Award)
Role: Principal Investigator
Description: The goal of this project is to evaluate for complex etiological processes involved in onset and course of substance use disorder in the first two years of college (and beyond). This is a critical time to study substance use as it tends to spike rapidly at this time, particularly among college students. Some students go on to develop a rather severe course of substance use disorder and less is known about what differentiates relatively benign, time-limited but heavy substance use versus rather severe and persistent substance use that results in significant physical and psychosocial impairments across time. For this study, an online survey is used to collect a comprehensive battery of assessments at two time points (12 months apart), including assessments of personality, substance use and substance use disorder, parent and family support, peer relationships, romantic relationship experiences, stress, depression, delinquency, and other factors. Romantic partners will be asked to complete the survey to allow for complex analyses of romantic partner dynamics as they relate to substance use disorder onset and course. Findings from this study will provide a better understanding of how key personality traits (related to impulsivity, aggression, and negative emotionality) work together with key aspects of social context (such as aspects of parent-child, peer, and romantic partner relationships) to influence the onset of alcohol and cannabis use disorder and overall course through the second year of college. Findings will be used to support a larger study that will aim to follow students after the years they are expected to graduate (when substance use tends to decline rapidly), as well as a new cohort of students with more comprehensive assessments across time. Findings will also be disseminated through publications and conferences with practical implications provided to better support students in their transition into and out of college. Please visit our study Facebook page to stay up to date about this project.
Persistence of Alcohol Use Disorders: Person and Environment Effects ($148,000 total costs, NIH-NIAAA R03 AA024282 award)
Role: Principal Investigator
Description: There is consistent evidence for the influence of person-environment interplay in the development of adolescent substance use (SU) and substance use disorders (SUDs), such that adverse environmental contexts appear to amplify dispositional risk and protective environmental contexts appear to offset dispositional risk for SU. Although this has been demonstrated across key adolescent family, peer, and school factors in relation to adolescent SU, there is a dearth of research evaluating person-environment interplay in relation to adult onset SUDs or overall SUD course (i.e., recurrence, desistence) into adulthood. Given that the majority of SUDs are adult onset and that recurrent SUD is associated with particularly problematic health consequences (e.g., early death), it is crucial to fill this gap. I hypothesize that similar mechanisms of person-environment interplay that have been demonstrated for adolescent SU continue to operate in adulthood, but that the environmental factors that offset or amplify risk for adult onset and recurrent SUD course will be those that are most relevant to adult development. Thus, much like aspects of the adolescent parent-child, peer, and school context are expected to moderate dispositional risk for adolescent onset SUD, aspects of adult romantic partner, family, peer, education, and employment context are expected to moderate dispositional risk for adult onset SUD and overall course. I expect distal environmental contexts (those that happened long ago, i.e., adolescence) will only be relevant to adult onset SUD and recurrence insofar as they are mediated through more proximal adult environmental contexts (e.g., adult peer and romantic partner characteristics). To investigate these hypotheses, a series secondary analyses of the population-based Minnesota Twin and Family Study (MTFS; R37DA005147, R01AA009367). The MTFS (N = 2,769, 52% female) included six prospective waves of rich data collected from preadolescence (age 11) through young adulthood (age 29). In this study, dispositional risk is measured using personality scales shown to be highly relevant to SUDs (aggressive undercontrol, negative emotionality, and constraint). This study focuses on alcohol use disorder given it is the most prevalent SUD, but will directly compare similarity of etiologies with illicit drug use disorder (e.g., cannabis). This study is innovative because it will evaluate person-environment interplay in relation to trajectories of clinically diagnosed SUDs rather than focusing on adolescent SU alone. Investigation of the proposed hypotheses will elucidate key factors important to disrupting or amplifying the cascading development of recurrent SU problems, which provides invaluable information regarding the most critical and cost-effective points of entry for SUD prevention and intervention. This study is significant as it will address a key gap in the research and will advance knowledge on the etiology of SUD onset and trajectory. Findings will clarify which environmental contexts are most relevant to amplifying or offsetting risk for developmentally-limited versus recurrent SUD course, which is crucial to guiding prevention not only in adolescence, but also in early and later young adulthood when SUDs are most prevalent.
Other Ongoing Research Collaborations:
I am affiliated with the Minnesota Center for Twin and Family Research. The MCTFR is comprised of two major longitudinal studies of twins, siblings, and parents (PIs: William Iacono and Matt McGue). The Minnesota Twin and Family Study (MTFS) study follows two cohorts of twins every 3-4 years covering pre-adolescence (age 11) through young adulthood (age 29). Over 1,300 sets of twins participated in the MTFS with high retention rates across time points. A rich battery of assessments were conducted, including clinical interviews, psychophysiological assessments, and self-report surveys covering a variety of social and environmental factors, as well as reports of substance use behavior. The Sibling Interaction and Behavior Study (SIBS) followed over 600 families in early adolescence through young adulthood. Three types of families participated: families where both children were adopted and not genetically related to one another, families where both children where full biological offspri ng of their parents, and families where one child was adopted and the other was the biological offspring of parents. Like the MTFS, a rich battery of biopsychosocial assessments were conducted, including video-recorded family and sibling interactions. More information about the MCTFR can be found here: http://www.ncbi.nlm.nih.gov/pubmed/17254440 .
I am very grateful for those of you who are participating in the College Experiences study, as well as those that participated in the MCTFR studies. We have and will learn so much about adolescent and young adult development because of you!