Behavioral economic demand for alcohol among young adults who engage in simultaneous alcohol and marijuana use

Abstract

Background: Young adults (YAs) who engage in simultaneous alcohol and marijuana use (SAM) may combine substances due to enhanced subjective effects, and as a result, may place greater value (e.g., spend more resources) on alcohol relative to YAs who consume alcohol but do not engage in SAM. The aim of the current study was to evaluate behavioral economic demand for alcohol among YAs who reported SAM (n = 101) relative to alcohol use only (n = 316), and concurrent alcohol and marijuana use (CAM; n = 63). Methods: YAs (18–25 years old) recruited from the community completed an online assessment that included the Alcohol Purchase Task as well as past month alcohol, marijuana, and SAM use. Results: Analyses of covariance demonstrated that YAs who reported SAM had significantly higher O_max values (maximum overall expenditures on alcohol) than those who reported CAM, and both YAs who reported SAM and alcohol-only had significantly higher P_max values (maximum inelastic price per drink) than YAs who reported CAM. Conclusions: YAs that engage in SAM show an increased willingness to spend resources on alcohol. Elevated demand is not associated with concurrent use of multiple substances, but rather the combined (i.e., overlapping) use of substances.

Keywords:

• Simultaneous alcohol and marijuana use
• young adults
• behavioral economics
• alcohol demand
• reinforcing value

Author contributions

JJR conceived the manuscript’s primary aims, analyzed data, and primarily drafted the manuscript. JMC assisted with interpretation of the results and contributed to drafting the manuscript. CML conceived the overall study design, oversaw data collection, and contributed to drafting of the manuscript. All authors read and approved the final manuscript.

Additional information

Funding

This work was supported by National Institute on Alcohol Abuse and Alcoholism (NIAAA) R01AA022087 (PI: Lee), R01AA022087-03S1 (PI: Lee), F32AA025263 (PI: Cadigan), and by National Institute on Drug Abuse (NIDA) R21DA045092 (PI: Ramirez). NIAAA and NIDA had no role in the study design, collection, analysis or interpretation of the data, writing the manuscript, or the decision to submit the paper for publication. The opinions expressed in this article are solely those of the authors.