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.
Geriatricians, primary care providers, older cannabis users
Dose-response relationship between cannabis use frequency and subjective cognitive decline (p < 0.001)
What the researchers 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).
Why it 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 numbers in context
100,685 participants aged 45+; five BRFSS cycles; dose-response trend p < 0.001 for both SCD and SCD-related functional limitations.
How the study worked
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.
What this study cannot 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.
How to read the evidence
Very large nationally representative sample with dose-response pattern, but cross-sectional design and reliance on self-report limit causal interpretation.
When this study was published
Published 2025
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.
Questions still open
- 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?
Common questions
Did cannabis use correlate with memory problems in older adults?
Does this prove cannabis causes cognitive decline?
Read the original research
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
Citation
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
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