Exploring the link between cannabis use and future substance use in younger adults

Abstract

Introduction

Young adults report high rates of current cannabis use. The increase of legalised cannabis in the United States has led to greater access and availability, causing cannabis to become the new “gateway” drug. This study examined the number of young people who try cannabis before alcohol or tobacco and the link between the initiation of cannabis first and substance use in young adults. 

Methods:

Data were analysed as part of the Population Assessment of Tobacco and Health study. Information was gathered in relation to who had ever tried alcohol, cannabis, or tobacco and the age at first use of these substances.

Results

Using cannabis before alcohol and tobacco (6%) was rare.

Initiating cannabis before alcohol and tobacco were linked with increased odds of cannabis use, tobacco use and polysubstance use.

Starting use of cannabis at the same age as either alcohol or tobacco or trying cannabis after these substances was linked with increased odds of all substance use outcomes.

Conclusions

Cannabis initiation before alcohol and tobacco is uncommon and may even protect against future alcohol use.

Deterring cannabis initiation with multiple substances could have public health benefits.