Neuropsychological assessment in Adult Drug-Resistant Focal Epilepsy patients with Adjunctive Cannabidiol treatment.

Introduction: Drug-resistant focal epilepsy frequently affects memory, attention, language, and executive functions. While cannabidiol (CBD) is a known therapy, its cognitive impact remains understudied. Cognitive impairment in drug-resistant epilepsy involves static factors (lesions) and dynamic factors (seizures, discharges, medication effects, comorbidities, onset age, duration). Objective: To evaluate the cognitive status of adult patients with drug-resistant focal epilepsy before and after adjunctive CBD treatment. Methods: Prospective, open-label, before-and-after cohort study in patients aged 18–60 at a public hospital in Buenos Aires (6–9 months follow-up). Assessments covered verbal/nonverbal episodic memory, language, executive functions, and attention. Results: Among 44 patients, 38 were responders, 5 non-responders, and 1 worsened. Responders showed statistically significant improvements in verbal/visual memory, language, sustained attention, and shifting attention. Non-responders and worsened groups improved in verbal and visual memory. Depressive symptoms did not significantly impact performance. Conclusions: Unlike conventional therapies, CBD shows no negative cognitive impact in drug-resistant focal epilepsy. Improvements in memory, language, and attention occurred regardless of seizure response.