Youth Exposure to Recreational Cannabis Legalization: Moderation of Effects by Sex and Parental Cannabis Use during Adolescence

Abstract

Objective

Few studies of recreational cannabis legalization (RCL) have assessed adolescents both before and after RCL or considered moderators of RCL effects. The present study tested whether RCL was more strongly associated with cannabis use for girls and among youth whose parents had a history of cannabis use during adolescence.

Method

Data were pooled from 940 adolescents from three intergenerational studies that began in Washington (where RCL was enacted in 2012), Oregon (RCL year = 2015), and New York (RCL year = 2021). Youth were assessed repeatedly from ages 13 to 18 years (k = 3,650 person–years) from 1999 to 2020 (prior to RCL in New York). Parent cannabis use at or before age 18 years (yes/no) was assessed prospectively during the parent’s adolescence. Multilevel models focused on the between-subjects effects of years of youth exposure to RCL on adolescents’ mean cannabis use likelihood, and interactions with child sex and parent use history.

Results

Child exposure to RCL was associated with a higher likelihood of cannabis use if their parents had a history of adolescent use, (Estimate [SE] = 0.67 [0.25], p = 0.008), versus no such history (Estimate [SE] = −0.05 [0.28], p = 0.855). RCL effects were not moderated by child sex.

Conclusions

The effects of RCL on adolescents’ cannabis use may depend on their parents’ history of using the drug. Identifying other moderators of RCL effects, and understanding the mechanisms of these risks and the ways that parents and communities can offset them, are prevention priorities.

PUBLIC HEALTH SIGNIFICANCE

(1) Adolescents’ use of cannabis may have intergenerational consequences, making it more likely their future offspring will use cannabis. (2) Whether or not recreational cannabis legalization influences adolescents’ cannabis use may depend on their parents’ cannabis use history. (3) Parenting in a state with liberalized cannabis policies may present new challenges and require that novel prevention resources be developed.

Keywords:

• Adolescence
• cannabis legalization
• longitudinal
• parent cannabis use
• sex differences

Acknowledgments

We report how we determined our sample size, all data exclusions (if any), all manipulations, and all measures in the study. All authors declare they have no conflicts of interest, financial or otherwise, to report. Analysis code is available on request from Stacey Tiberio ([email protected]). Archiving of data and study materials differs by study; contact David Kerr ([email protected]), Jennifer Bailey ([email protected]), and Kimberly Henry ([email protected]) for information on OYS/3GS, SSDP/TIP, and RYDS/RIGS, respectively. We acknowledge and appreciate the individuals who participated in our studies. This study was not preregistered. We also thank Sally Schwader for editorial assistance.

Disclosure statement

The authors report there are no competing interests to declare.

Additional information

Funding

This study was supported by funding from the National Institute on Drug Abuse awarded to (Oregon Youth Study¬–Three Generational Study [OYS-3GS] R01DA015485 awarded to Drs. Deborah Capaldi and David Kerr; Rochester Intergenerational Study [RIGS] R01DA020195 awarded to Dr. Kimberly Henry; Seattle Social Development Project–The Intergenerational Study [SSDP–TIP] R01DA023089, R01DA056371 awarded to Dr. Jennifer Bailey). Points of view reflect those of the authors and not the funding agency. The funding agency had no role in the design of the study, data collection or analysis, interpretation of results, or the decision to submit this manuscript for publication.