Nearly 73% of marijuana users continued using over a year, with early initiation and weekly use predicting persistence

In a national study of 26,204 adults, 2.4% of never-users initiated marijuana, 10.4% of former users returned, and 72.5% of current users continued over 12 months, with mental health problems and other substance use predicting transitions.

Choi, Namkee G et al.·Drug and alcohol dependence·2018·Strong EvidenceLongitudinal Cohort
RTHC-01622Longitudinal CohortStrong Evidence2018RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Longitudinal Cohort
Evidence
Strong Evidence
Sample
N=26,204

What This Study Found

Using data from the Population Assessment of Tobacco and Health study, researchers tracked marijuana use transitions over one year in over 26,000 US adults.

Among people who had never used marijuana, 2.36% initiated use. Among those who had used in the past but not recently, 10.42% returned to use. And among current users, 72.54% continued using, while 27.46% stopped.

The 18-24 age group was most likely to initiate, resume, or continue use. Mental health problems predicted both initiation among never-users and return to use among former users, suggesting marijuana use may partly reflect self-medication.

For continued use versus quitting, three factors stood out: initiating marijuana before age 18, using weekly or more frequently (2.34 times higher odds of continuing), and reporting use-related problems (1.40 times higher odds of continuing). Marijuana initiation and return to use were also associated with starting other substances during the same period.

Key Numbers

26,204 adults studied. Initiation among never-users: 2.36%. Return among former users: 10.42%. Continued use among current users: 72.54%. Ages 18-24 most likely to transition. Weekly+ use: AOR = 2.34 for continued use. Use problems: AOR = 1.40 for continued use. Initiation before age 18 predicted continuation.

How They Did This

Two waves of the Population Assessment of Tobacco and Health (PATH) Study were analyzed (N = 26,204 adults aged 18+). Multivariable logistic regression examined associations between Wave 1 characteristics and Wave 2 marijuana use status across three transition types: never-to-initiation, former-to-return, and continued use versus quitting.

Why This Research Matters

Understanding the patterns of marijuana use transitions helps target prevention and intervention efforts. The finding that early initiation, frequent use, and existing problems predict continued use identifies who is most likely to develop persistent patterns, while the link between mental health and initiation suggests a self-medication pathway that could be addressed clinically.

The Bigger Picture

These data provide a population-level view of marijuana use dynamics. The high continuation rate (73%) among current users, combined with the 10% return rate among former users, paints a picture of marijuana use as a persistent behavior once established, underscoring the importance of prevention before initiation.

What This Study Doesn't Tell Us

The one-year follow-up may not capture longer-term use trajectories. Self-reported marijuana use may be underreported. The PATH study did not distinguish between medical and recreational use. The analysis cannot determine whether mental health problems cause marijuana initiation or whether both share common causes.

Questions This Raises

  • ?Would treating mental health problems in young adults reduce marijuana initiation rates?
  • ?What happens to the 27% who quit, do they maintain abstinence long-term?
  • ?Could brief interventions at the weekly-use threshold prevent escalation to persistent use?

Trust & Context

Key Stat:
72.5% of current marijuana users continued using over 12 months
Evidence Grade:
This is a large national longitudinal study with over 26,000 participants, providing strong evidence on marijuana use transition patterns.
Study Age:
Published in 2018 using data from the Population Assessment of Tobacco and Health study.
Original Title:
Marijuana use among adults: Initiation, return to use, and continued use versus quitting over a one-year follow-up period.
Published In:
Drug and alcohol dependence, 182, 19-26 (2018)
Database ID:
RTHC-01622

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

Follows a group of people over time to track how outcomes develop.

What do these levels mean? →

Frequently Asked Questions

How likely am I to keep using marijuana?

In this national study, 72.5% of current users continued using over one year. The strongest predictors of continued use were starting before age 18, using weekly or more often, and already experiencing use-related problems.

What predicts starting marijuana for the first time?

Being aged 18-24, having mental health problems, and initiating other substances were all associated with starting marijuana use. Among never-users, 2.36% initiated over one year.

Read More on RethinkTHC

Cite This Study

RTHC-01622·https://rethinkthc.com/research/RTHC-01622

APA

Choi, Namkee G; DiNitto, Diana M; Marti, C Nathan. (2018). Marijuana use among adults: Initiation, return to use, and continued use versus quitting over a one-year follow-up period.. Drug and alcohol dependence, 182, 19-26. https://doi.org/10.1016/j.drugalcdep.2017.10.006

MLA

Choi, Namkee G, et al. "Marijuana use among adults: Initiation, return to use, and continued use versus quitting over a one-year follow-up period.." Drug and alcohol dependence, 2018. https://doi.org/10.1016/j.drugalcdep.2017.10.006

RethinkTHC

RethinkTHC Research Database. "Marijuana use among adults: Initiation, return to use, and c..." RTHC-01622. Retrieved from https://rethinkthc.com/research/choi-2018-marijuana-use-among-adults

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.