Dual cigarette and e-cigarette use was the strongest predictor of marijuana vaping initiation in young adults

In a prospective study of 2,327 college students, dual cigarette/e-cigarette use was the strongest predictor of starting marijuana vaping, while social networks with marijuana users and vape shop frequenters predicted escalation.

Pokhrel, Pallav et al.·Drug and alcohol dependence·2020·Strong EvidenceProspective Cohort
RTHC-02784Prospective CohortStrong Evidence2020RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Prospective Cohort
Evidence
Strong Evidence
Sample
Not reported

What This Study Found

Among 2,327 young adults followed for one year, dual cigarette/e-cigarette use at baseline was the strongest predictor of marijuana vaping initiation among non-marijuana users. Social networks with more regular marijuana users predicted marijuana vaping initiation. Among existing e-cigarette and marijuana users, having social networks with people who frequented vape shops predicted increased marijuana vaping over time.

Key Numbers

2,327 young adults; mean age 21.2; 54% women; 1-year follow-up (2017-2019); dual cigarette/e-cigarette use strongest predictor of initiation; vape shop social networks predicted escalation.

How They Did This

One-year prospective study of 2,327 young adults (mean age 21.2, 54% women) at 2-year and 4-year colleges in Hawaii, using validated measures of substance use, social network characteristics, and marketing exposure at baseline and follow-up.

Why This Research Matters

Marijuana vaping is increasing rapidly among young adults but its risk factors are poorly understood. Identifying that dual tobacco product use and social networks drive initiation helps target prevention.

The Bigger Picture

The vape shop connection is notable: social environments where nicotine vaping is normalized appear to facilitate marijuana vaping escalation. This suggests that marijuana vaping prevention may need to address the broader vaping culture, not just marijuana-specific messaging.

What This Study Doesn't Tell Us

Hawaii sample (unique cultural and legal context); 1-year follow-up may miss longer-term patterns; self-report measures; college students may not represent all young adults; did not assess vaping device types or THC concentrations.

Questions This Raises

  • ?Do vape shops actively facilitate marijuana vaping adoption?
  • ?Would e-cigarette regulation indirectly reduce marijuana vaping initiation?

Trust & Context

Key Stat:
Dual tobacco product use strongest predictor of marijuana vaping onset
Evidence Grade:
Strong: large prospective design with 1-year follow-up and validated measures.
Study Age:
Published 2020.
Original Title:
Predictors of marijuana vaping onset and escalation among young adults.
Published In:
Drug and alcohol dependence, 216, 108320 (2020)
Database ID:
RTHC-02784

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Enrolls participants and follows them forward in time.

What do these levels mean? →

Frequently Asked Questions

What predicts who will start vaping marijuana?

The strongest predictor was already using both cigarettes and e-cigarettes. Having more marijuana users in your social network also predicted initiation, but e-cigarette users and cigarette smokers in your network did not.

What makes marijuana vaping get worse over time?

Among people already using e-cigarettes and marijuana, having social networks that included people who frequented vape shops predicted increased marijuana vaping one year later.

Read More on RethinkTHC

Cite This Study

RTHC-02784·https://rethinkthc.com/research/RTHC-02784

APA

Pokhrel, Pallav; Fagan, Pebbles; Kawamoto, Crissy T; Okamoto, Scott K; Herzog, Thaddeus A. (2020). Predictors of marijuana vaping onset and escalation among young adults.. Drug and alcohol dependence, 216, 108320. https://doi.org/10.1016/j.drugalcdep.2020.108320

MLA

Pokhrel, Pallav, et al. "Predictors of marijuana vaping onset and escalation among young adults.." Drug and alcohol dependence, 2020. https://doi.org/10.1016/j.drugalcdep.2020.108320

RethinkTHC

RethinkTHC Research Database. "Predictors of marijuana vaping onset and escalation among yo..." RTHC-02784. Retrieved from https://rethinkthc.com/research/pokhrel-2020-predictors-of-marijuana-vaping

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.