Children with later bedtimes and less sleep were more likely to try marijuana by age 15 | Research

The takeaway

In a national birth cohort of 1,514 children, later bedtimes at age 5 and shorter sleep at age 9 predicted higher odds of trying marijuana by age 15, even after controlling for family and demographic factors.

Pediatricians, child development specialists, sleep researchers, and substance use prevention professionals

Later bedtime at age 5 predicted marijuana use at 15 (aOR 1.26)

What the researchers found

At age 15, later bedtime (aOR 1.35) and shorter sleep at age 9 (aOR 1.19) were associated with greater odds of trying marijuana. Later bedtimes at age 5 also predicted marijuana use (aOR 1.26). Cross-sectionally at 15, later bedtime (aOR 1.35) was associated with marijuana use.

Why it matters

Identifying childhood sleep problems as a modifiable risk factor for adolescent substance use opens a window for early prevention long before drug exposure becomes a concern.

The numbers in context

1,514 adolescents from 20 US cities; later bedtime at age 5 predicted marijuana use at 15 (aOR 1.26); shorter sleep at age 9 predicted marijuana use (aOR 1.19); at age 15: later bedtime aOR 1.35 for marijuana

How the study worked

Prospective longitudinal analysis of the Future of Families and Child Wellbeing Study, a national birth cohort from 20 US cities. Parent-reported sleep measures at ages 3, 5, and 9 were linked to self-reported marijuana and alcohol use at age 15 (n = 1,514). Logistic regressions adjusted for sex, race/ethnicity, family structure, income, and caregiver education.

What this study cannot tell us

Observational design cannot prove sleep problems cause later substance use; parent-reported sleep for younger ages, self-reported at 15; unmeasured confounders possible; bedtime is a proxy for sleep quality; urban birth cohort may not generalize to all settings

How to read the evidence

Prospective longitudinal birth cohort with appropriate confounder adjustment, though limited by observational design and sleep measurement proxies.

When this study was published

2024 study using longitudinal data from ages 3-15

The bigger picture

Sleep is increasingly recognized as foundational to child development. This study adds substance use risk to the growing list of adverse outcomes associated with poor childhood sleep habits.

Questions still open

Would improving childhood sleep habits reduce adolescent substance use? Is the relationship mediated through self-regulation or other developmental pathways?

Common questions

How did childhood sleep predict marijuana use?

Children who had later bedtimes at age 5 were 26% more likely to try marijuana by age 15. Those with shorter sleep duration at age 9 were 19% more likely. These associations held after accounting for family income, structure, race/ethnicity, and other factors.

Does this mean poor sleep causes drug use?

Not necessarily. The study shows a prospective association, meaning childhood sleep problems preceded the marijuana use by years. However, both could be driven by shared underlying factors like family environment or self-regulation difficulties. Still, the authors argue protecting childhood sleep habits may reduce substance use risk.

Read the original research

Childhood sleep is prospectively associated with adolescent alcohol and marijuana use.

Annals of epidemiology, 98, 25-31

View on PubMed ↗Publisher’s paper ↗

Citation

Krishnan, Akshay S; Reichenberger, David A; Strayer, Stephen M; Master, Lindsay; Russell, Michael A; Buxton, Orfeu M; Hale, Lauren; Chang, Anne-Marie. (2024). Childhood sleep is prospectively associated with adolescent alcohol and marijuana use.. Annals of epidemiology, 98, 25-31. https://doi.org/10.1016/j.annepidem.2024.07.048