EC Neurology

Objective: The aim of this study is to assess the cognitive status in adult patients with focal drug-resistant epilepsy before and after the use of cannabidiol (CBD).

Method: A prospective, observational, open-label, prospective cohort study was conducted with an uncontrolled before-after design. Patients aged 18 to 60 years, recruited from a public hospital in Buenos Aires, Argentina. The follow-up period for each subject was 6 to 9 months. We analyzed by specific domain: episodic memory verbal and non-verbal, language, executive functions and attention.

Results: Forty-four patients were included. They were separated into three groups regarding treatment efficacy: responders (n = 38), non-responders (n = 5) and worsening (n = 1).

In the responders group we found statistically significant improvements in verbal memory, visual memory, language, sustained attention and alternating attention. In the non-responders and worsening group, we found significant improvements in verbal memory and visual memory.

Conclusion: Our results suggest that, unlike conventional anti-seizure therapies, CBD does not have a negative impact on the cognitive status of patients. Notably, we found an improvement in verbal and visual memory, language and attention.

 Keywords: Epilepsy; Cannabidiol; Cognition

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