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Study breakdown

Daily Cannabis Use Amplifies Cognitive Problems in People With Chronic Conditions

Cross SectionalStrong evidence
The takeaway

A massive national survey found that daily cannabis use was associated with 145% higher rates of cognitive difficulty among people with chronic medical conditions.

Cannabis users with chronic health conditions, primary care providers, cognitive health researchers

145% higher cognitive difficulty with daily cannabis use plus chronic conditions

What the researchers found

Among 94,918 U.S. adults, daily cannabis use was associated with 145% higher prevalence of difficulty concentrating, remembering, or making decisions among those with chronic conditions, and 183% higher among those without. Monthly use showed 76% and 97% increases respectively.

Why it matters

With millions of Americans using cannabis while managing chronic conditions, understanding how cannabis interacts with existing cognitive challenges is critical for informed decision-making.

The numbers in context

94,918 participants. Cognitive difficulty prevalence: 12.7% overall, 17.6% with chronic conditions vs 5.7% without. Daily cannabis use: 7.4%. Monthly use: 14.9%. Daily use + chronic condition: 145% higher cognitive difficulty.

How the study worked

Cross-sectional analysis of the 2022 Behavioral Risk Factor Surveillance System (BRFSS), a nationally representative telephone survey of U.S. adults aged 18+.

What this study cannot tell us

Cross-sectional design cannot determine if cannabis causes cognitive difficulty or if people with cognitive problems use more cannabis. Self-reported data. Cannot account for cannabis potency, strain, or method of use.

How to read the evidence

Very large nationally representative sample provides strong population-level evidence, though cross-sectional design limits causal inference.

When this study was published

2025 study using 2022 BRFSS data, the most current available.

The bigger picture

This study challenges the assumption that cannabis is cognitively harmless, particularly for the large population of people already dealing with chronic health conditions that affect thinking and memory.

Questions still open

  • Does the cognitive impact differ by type of cannabis product or consumption method? Are certain chronic conditions more susceptible to cannabis-related cognitive effects? Is the association reversible with cessation?

Common questions

Does cannabis affect thinking and memory?
This study found daily cannabis use was associated with substantially higher rates of cognitive difficulty across the U.S. population, with the strongest effects seen in people without pre-existing conditions (183% increase) and significant effects in those with chronic conditions (145% increase).
Is occasional cannabis use safer for cognition than daily use?
Monthly cannabis use was associated with smaller but still significant increases in cognitive difficulty (76-97%), suggesting a dose-response pattern where more frequent use correlates with more cognitive impact.

Read the original research

Cognitive Difficulty Concentrating, Remembering, or Making Decisions According to Chronic Medical Conditions and Cannabis Use Among US Adults in 2022.

Innovations in clinical neuroscience, 22(7-9), 32-39

Citation

Merrill, Ray M. (2025). Cognitive Difficulty Concentrating, Remembering, or Making Decisions According to Chronic Medical Conditions and Cannabis Use Among US Adults in 2022.. Innovations in clinical neuroscience, 22(7-9), 32-39.

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