Temporal Association Between Reported Use of Psychoactive Substances and Cognitive Function in Individuals With Multiple Sclerosis.
Jeeyeon Kim, Dawn M Ehde, Kevin N Alschuler and 2 others
PMID 40840668WHAT IT FOUND
In people with MS, using caffeine was linked to better self-reported thinking and faster processing speed.
Alcohol use was linked to worse working memory. Cannabis use was linked to worse self-reported thinking, but no change in objective tests.
Key findings
01Caffeine use was associated with better perceived cognitive function and faster processing speed, particularly in those with lower average caffeine consumption.
02Alcohol use was associated with poorer working memory performance.
03Cannabis use was associated with increased self-reported cognitive difficulties but showed no significant relationship with objective cognitive measures.
STILL TO COME
How it was doneWhat they foundWhat it means for SLPs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study design is observational, so causal conclusions cannot be drawn. The 14-day monitoring period may not capture long-term or cumulative effects of substance use. Substance use was self-reported, which is subject to recall and social desirability bias. The study did not assess dose, duration, or chemical composition (e.g., THC vs CBD) of substances used. The EMA items for substance use and perceived cognition were not previously validated in people with MS. Low prevalence of nicotine and opioid use limited statistical power for these substances. Temporal alignment of substance use and cognitive testing was approximate (e.g., use since last assessment, which could be 3-6 hours prior).
Declared interests
None declared.
The easy way to misread this
Do not interpret these associations as evidence that caffeine improves MS-related cognitive impairment or that alcohol/cannabis cause long-term decline. The effects were transient and within-person, and the study did not establish causality or dose-response relationships.
Summarised by AI from the full paper, without a clinician reviewing it. Check it against the source before it changes what you do. Read it on PubMed →