Project Summary
An estimated 1.5 million U.S. young adults are dual users of cannabis and tobacco. Dual users
experience higher rates of dependence and difficulty quitting, compounding their risk of long-
term health problems and posing a unique public health challenge. Drive to obtain and use
substances despite cost is a centerpiece of addiction. Overvaluation of substances is captured
by the concept behavioral economic demand (referred to hereafter as demand). Progress in
preventing and treating dual use among young adults requires studying demand for cannabis
and tobacco in three key areas. First, it is essential to characterize demand for cannabis and
tobacco among users of both substances and understand how demand for each substance
changes over time (Aim 1). Second, critical gaps in our understanding of dual use include not
knowing how the link between demand and substance-specific outcomes, such as dependence
and quit attempts operates among dual users, and whether demand for one substance impacts
outcomes for the co-used substance (Aim 2). Third, the lack of a theory-based, explanatory
model connecting demand to dual use is a barrier to progress in prevention and treatment of
dual use. Social cognitive theory (SCT) is a widely used behavioral health model for
understanding substance use, containing modifiable factors such as expectancies, perceptions
of risk and social acceptability, and identity, which has yet to be applied to dual use of cannabis
and tobacco. This study will identify SCT factors linked with demand and dual use (Aim 3),
providing actionable targets of intervention. Addressing these aims will create significant
progress in preventing and treating a unique public health problem among a high-risk group,
consistent with NIDA’s mission. A prospective, cohort design will be used to measure behavioral
economic demand for tobacco and cannabis, current use of tobacco and cannabis and related
behavioral health effects, and SCT factors among 250 young adults (age 18-25) current tobacco
and cannabis users in San Diego, CA at three, 75-minute visits: baseline, month 6, and month
12. The study will be conducted by an experienced university research lab in San Diego, CA
with a track record of recruiting and retaining tobacco and cannabis users, in collaboration with
an expert in behavioral economic demand measurement and a leading biostatistician. This
project will provide students a high-quality research experience in the execution, analysis, and
reporting of the study, consistent with the R16 aim.