Cannabis users over 45 reported more memory and thinking problems than non-users

In over 100,000 US adults aged 45+, past-month marijuana users reported higher rates of subjective cognitive decline, with a dose-response pattern showing more frequent use linked to more cognitive complaints.

Chen, Xiao et al.·Journal of Alzheimer's disease : JAD·2025·Moderate EvidenceCross-Sectional
RTHC-06205Cross SectionalModerate Evidence2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
N=100,685

What This Study Found

Past-month marijuana users reported higher rates of subjective cognitive decline and SCD-related functional limitations compared to non-users, with a significant dose-response trend (p < 0.001).

Key Numbers

100,685 participants aged 45+; five BRFSS cycles; dose-response trend p < 0.001 for both SCD and SCD-related functional limitations.

How They Did This

Cross-sectional analysis of 100,685 participants from five BRFSS survey cycles; self-reported past-month marijuana use categorized by frequency; subjective cognitive decline and functional limitations assessed.

Why This Research Matters

As cannabis use grows among older adults, understanding whether it is associated with cognitive complaints in this age group is important for clinical guidance.

The Bigger Picture

Whether cannabis use contributes to or merely correlates with cognitive decline in aging populations remains unresolved, but these self-reported data flag a concerning pattern.

What This Study Doesn't Tell Us

Cross-sectional design cannot determine causation; self-reported marijuana use and cognitive decline; no objective cognitive testing; potential confounders including other substance use.

Questions This Raises

  • ?Does marijuana use accelerate cognitive decline in older adults, or do people with cognitive symptoms self-medicate?
  • ?Would prospective studies with objective testing confirm this association?

Trust & Context

Key Stat:
Dose-response relationship between cannabis use frequency and subjective cognitive decline (p < 0.001)
Evidence Grade:
Very large nationally representative sample with dose-response pattern, but cross-sectional design and reliance on self-report limit causal interpretation.
Study Age:
Published 2025
Original Title:
Marijuana use and subjective cognitive decline in middle-aged and older adults: Analysis of the behavioral risk factor surveillance system survey.
Published In:
Journal of Alzheimer's disease : JAD, 105(1), 280-291 (2025)
Database ID:
RTHC-06205

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

A snapshot of a population at one point in time.

What do these levels mean? →

Frequently Asked Questions

Did cannabis use correlate with memory problems in older adults?

Yes. Past-month marijuana users aged 45+ reported more subjective cognitive decline and related functional limitations, with more frequent use linked to more complaints.

Does this prove cannabis causes cognitive decline?

No. The cross-sectional design cannot establish causation. People experiencing cognitive decline may use cannabis to cope rather than cannabis causing the decline.

Read More on RethinkTHC

Cite This Study

RTHC-06205·https://rethinkthc.com/research/RTHC-06205

APA

Chen, Xiao; Wang, Peilu; Tang, Yilin; Veldheer, Susan; Geng, Tingting; Sun, Liang; Li, Yaqi; Gao, Xiang. (2025). Marijuana use and subjective cognitive decline in middle-aged and older adults: Analysis of the behavioral risk factor surveillance system survey.. Journal of Alzheimer's disease : JAD, 105(1), 280-291. https://doi.org/10.1177/13872877251327164

MLA

Chen, Xiao, et al. "Marijuana use and subjective cognitive decline in middle-aged and older adults: Analysis of the behavioral risk factor surveillance system survey.." Journal of Alzheimer's disease : JAD, 2025. https://doi.org/10.1177/13872877251327164

RethinkTHC

RethinkTHC Research Database. "Marijuana use and subjective cognitive decline in middle-age..." RTHC-06205. Retrieved from https://rethinkthc.com/research/chen-2025-marijuana-use-and-subjective

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.