Tobacco and Marijuana Co-Use Among Emerging Adults in California
Creators: name: University Of California Office Of The President
Publisher: name: University of California Office of the President
publisherIdentifier: https://ror.org/00dmfq477
publisherIdentifierScheme: ROR
Year: 2024

description: The goal of this study is to fill a large knowledge gap about the longitudinal effects of nicotine on the developing adolescent brain. Despite upticks in alcohol and marijuana use among adolescents, nicotine is still the most preventable cause of disease and death worldwide. The majority (88%) of adult smokers began smoking in the adolescent years. Public health scholars and addiction scientists have noted that the best way to reduce death by smoking is to prevent people from smoking in the first place. This means scientists need to study two key questions: 1) are there psychological and neural mechanisms in adolescent smokers that distinguishes them from non-smokers? and 2) what are the psychological and neural consequences of nicotine use during adolescence, particularly as youth transition from casual use to dependence? A few published studies, including our own, have begun to address the first question but there is virtually no research on the second. The proposed study will thus be the first of its kind to address this question using a longitudinal approach that examines brain structure and function at two timepoints. Success on this project will make a significant contribution to the field, as only 7% of MRI studies of adolescent substance users are focused on nicotine, which is considerably less than MRI studies on marijuana (45%) and alcohol (36%). Our design is straightforward. The research team will leverage an ongoing study (funded by the William T. Grant Foundation) with a cohort of adolescent smokers and nonsmokers. The plan is to use current psychological, neuroimaging and substance use data from this cohort as a baseline measure. Funds from the TRDRP will be used to collect a second wave of data that will serve as a longitudinal follow-up. We will continue to use state-of-the-art neuroimaging tools that measure brain size, brain function, and brain communication among critical regions to determine the impact of nicotine on the adolescent brain across the critical window of late adolescence and early adulthood. It is during this time that individuals report highest incidence of dependence onset. Our research will uncover whether there are neurobiological explanations for this shift from use to dependence and, secondly, how smoking derails the brain from progressing along a healthy developmental pathway. One arm of the research is to uncover the additive effects of nicotine, alcohol, and marijuana on the brain, given the frequency with which adolescents co-use these substances. In addition to the logistical and financial benefits of taking advantage of access to adolescents in the ongoing study, we have detailed demographic information about these youth regarding economic resources, leaving us well-positioned to examine the relation between socioeconomic status and nicotine use. This sorely understudied question is critically important because youth with greater economic disadvantage exhibit higher rates of smoking behavior than more economically advantaged youth, which may account for discrepancies among these populations in academic, health and psychological outcomes due to nicotine's powerfully toxic effects on the developing brain. The team is led by Principal Investigator Dr. Galvan, an expert in adolescent brain development with a track record of cross-sectional neuroimaging research in adolescent smokers, and Co-Investigator Dr. Lara Ray, a highly respected and prolific researcher at the intersection of addiction and neuroscience in young adults. Dr. Susan Tapert, a world-renowned expert in the area of neurocognitive functioning in adolescent substance users who has conducted longitudinal studies of youth, will serve as a consultant. The investigators have a strong reputation for dissemination of research to scientific and lay audiences alike. This tradition will continue with findings from the current proposal, to be circulated to adolescents, parents and educators. Dr. Galvan's well-established partnerships with middle and high schools and summer programs for economically-disadvantaged youth will ensure success of this goal.