# Trends in lifetime controlled drug use and associated risk factors among Japanese Junior High School Students: Findings from Nationwide Surveys, 2016–2024

## TL;DR

Drug use among Japanese junior high students has decreased from 2016 to 2024, but remains linked to social and behavioral risk factors.

## Contribution

This study identifies specific sociodemographic and behavioral risk factors associated with controlled drug use in Japanese adolescents using nationwide survey data.

## Key findings

- Lifetime controlled drug use prevalence dropped from 0.5% in 2016 to 0.2% in 2024.
- Risk factors include male sex, alcohol use, permissive attitudes, and poor family communication.
- School dissatisfaction and social isolation significantly increase drug use likelihood.

## Abstract

To examine trends in the lifetime prevalence of controlled drug use among Japanese junior high school students (aged 12–15 years) between 2016 and 2024 and to identify associated sociodemographic, behavioral, and psychosocial factors.

We analyzed data from 214,011 students across four nationwide surveys. The outcome was lifetime use of controlled drugs, including marijuana, solvents, methamphetamine, and new psychoactive substances. Predictors included demographic characteristics, substance‐related behaviors and attitudes, daily routines, and social relationships. Design‐weighted logistic regression was used to estimate the prevalence and assess associated risk factors.

The lifetime prevalence of controlled drug use showed a clear decreasing trend over the study period, declining from 0.5% (95% confidence interval [CI]: 0.4–0.5) in 2016 to 0.2% (95% CI: 0.1–0.2) in 2024. Similar downward trends were observed for all substances. While perceived drug access and permissiveness declined, tolerant attitudes toward marijuana slightly increased. Invitations to use drugs also became more common. Risk factors for controlled drug use included male sex, alcohol and tobacco use, permissive attitudes, drug invitations, irregular routines, school dissatisfaction, limited friendships, and poor family communication. The combination of multiple social risk factors, particularly when coupled with school dissatisfaction, social isolation, and limited parental consultation, significantly amplified the likelihood of drug use.

This repeated cross‐sectional analysis indicated that lifetime use of controlled drugs among Japanese adolescents is rare and continues to decline. However, usage remains concentrated among students with overlapping behavioral and social vulnerabilities. Prevention strategies should therefore prioritize these at‐risk groups.