One year of CBD treatment did not harm cognitive function in children with treatment-resistant epilepsy | Research

The takeaway

Children and teenagers with treatment-resistant epilepsy showed no cognitive decline after one year of add-on CBD therapy, with a nonsignificant trend toward improvement in some areas.

Parents of children with epilepsy considering CBD treatment, pediatric neurologists prescribing cannabidiol, and researchers tracking long-term CBD safety.

No significant cognitive decline after 1 year of CBD in pediatric epilepsy

What the researchers found

Among 38 pediatric patients (ages 3-19) with treatment-resistant epilepsy, those who completed cognitive testing showed no significant changes after one year of CBD. There was a nonsignificant trend toward improvement in some cognitive domains. Adaptive behavior scores also remained stable.

Why it matters

Parents and clinicians worry about cognitive side effects of adding another medication, especially for children already on multiple anticonvulsants. This study provides reassurance that CBD does not appear to worsen cognition over one year.

The numbers in context

38 participants ages 3-19. 24 were unable to complete cognitive testing due to severity of impairment. Among those tested, no statistically significant cognitive changes. Adaptive behavior scores unchanged after one year.

How the study worked

Open-label prospective study of 38 participants with treatment-resistant epilepsy receiving pharmaceutical CBD (Epidiolex) as add-on treatment. Cognition assessed with NIH Toolbox Cognition Battery at baseline and one year. For cognitively impaired participants unable to complete testing, caregivers completed the ABAS-II.

What this study cannot tell us

Open-label design without a control group. Small sample with high attrition (24 of 38 could not complete cognitive testing). Practice effects from repeated testing could mask subtle declines.

How to read the evidence

Prospective study with validated cognitive measures, but small open-label sample without a control group.

When this study was published

2020 study. Part of ongoing safety monitoring for pharmaceutical CBD (Epidiolex) in pediatric epilepsy.

The bigger picture

As CBD becomes an established add-on treatment for severe epilepsy, long-term safety data on cognition are essential. This study adds to the evidence that CBD is cognitively safe in the pediatric population most likely to receive it.

Questions still open

Would longer follow-up reveal any cognitive effects? Could CBD actually improve cognition in some patients by reducing seizure burden? Would results differ with higher or lower CBD doses?

Common questions

Did CBD improve cognition in these children?

There was a nonsignificant trend toward improvement in some cognitive domains, but the study was not designed or powered to detect cognitive improvements.

Why could so many participants not complete cognitive testing?

24 of 38 participants had cognitive impairment too severe to complete standardized testing. This is common in treatment-resistant epilepsy populations, where seizures and multiple medications can significantly affect cognitive function.

Read the original research

Cognitive function and adaptive skills after a one-year trial of cannabidiol (CBD) in a pediatric sample with treatment-resistant epilepsy.

Epilepsy & behavior : E&B, 111, 107299

View on PubMed ↗Publisher’s paper ↗

Citation

Thompson, Matthew D; Martin, Roy C; Grayson, Leslie P; Ampah, Steve B; Cutter, Gary; Szaflarski, Jerzy P; Bebin, E Martina. (2020). Cognitive function and adaptive skills after a one-year trial of cannabidiol (CBD) in a pediatric sample with treatment-resistant epilepsy.. Epilepsy & behavior : E&B, 111, 107299. https://doi.org/10.1016/j.yebeh.2020.107299